Surfactant-enhanced anaerobic acidogenesis of Canna indica L. by rumen cultures.

PubMed

Yue, Zheng-Bo; Yu, Han-Qing; Hu, Zhen-Hu; Harada, Hideki; Li, Yu-You

2008-06-01

Polyoxyethylene sorbitan monoolate (Tween 80) was used to enhance the anaerobic acidogenesis of Canna indica L. (canna) by rumen culture in this study. Dose of Tween 80 at 1 ml/l enhanced the volatile fatty acids (VFA) production from the acidogenesis of canna compared to the control. However, Tween 80 at higher dosages than 5 ml/l inhibited the rumen microbial activity and reduced the VFA yield. Response surface methodology was successfully used to optimize the VFA yield. A maximum of VFA yield of 0.147 g/g total solids (TS) added was obtained at canna and Tween 80 concentrations of 6.3g TS/l and 2.0 ml/l, respectively. Dosage of Tween 80 at 1-3.75 ml/l reduced the unproductive adsorption of microbes or enzymes on the lignin part in canna and increased microbial activity. A high VFA production was achieved from canna presoaked with Tween 80, suggesting that the structure of canna was disrupted by Tween 80.

Effect of Agitation on Acidogenesis Stage of Two-Stage Anaerobic Digestion of Palm Oil Mill Effluent (POME) into Biogas

NASA Astrophysics Data System (ADS)

Trisakti, B.; Irvan; Adipasah, H.; Taslim; Turmuzi, M.

2017-03-01

The acidogenesis stage in two-stage anaerobic digestion of palm oil mill effluent (POME) was studied in a continuous stirred tank reactor (CSTR). This research investigated the effect of agitation rate on the growth of microorganisms, the degradation of organic substances, and volatile fatty acids (VFA) production and composition. Initially, the suitable loading up was determined by varying the HRT 6.7, 5.0, and 4.0 days in a 2 L CSTR with agitation rate 50 rpm, pH 6.0 ± 0.2, at room temperature. Next, effect of agitation on the process was determined by varying agitation rate at 25, 50, 100, and 200 rpm. Analysis of total solids (TS), volatile solids (VS), total suspended solids (TSS), volatile suspended solids (VSS), chemical oxygen demand (COD), and volatile fatty acids (VFA) were conducted in order to study the growth of microorganisms and their abilities in converting organic compound to produce VFA. The highest growth of microorganisms was achieved at HRT 4.0 day with microorganism concentration was 20.62 mg VSS/L and COD reduction was 15.7%. The highest production of total VFA achieved was 5,766.61 mg/L mg/L at agitation rate 200 rpm, with concentration of acetic acid, propionic acid and butyric acid were 1,889.23; 1,161.43; and 2,725.95 mg/L, respectively. While degradation VS and COD were 16.61 and 38.79%.

On-line removal of volatile fatty acids from CELSS anaerobic bioreactor via nanofiltration

NASA Technical Reports Server (NTRS)

Colon, Guillermo

1995-01-01

The CELSS (controlled ecological life support system) resource recovery system, which is a waste processing system, uses aerobic and anaerobic bioreactors to recover plants nutrients and secondary foods from the inedible biomass. The anaerobic degradation of the inedible biomass by means of culture of rumen bacteria,generates organic compounds such as volatile fatty acids (acetic, propionic, butyric, VFA) and ammonia. The presence of VFA in the bioreactor medium at fairly low concentrations decreases the microbial population's metabolic reactions due to end-product inhibition. Technologies to remove VFA continuously from the bioreactor are of high interest. Several candidate technologies were analyzed, such as organic solvent liquid-liquid extraction, adsorption and/or ion exchange, dialysis, electrodialysis, and pressure driven membrane separation processes. The proposed technique for the on-line removal of VFA from the anaerobic bioreactor was a nanofiltration membrane recycle bioreactor. In order to establish the nanofiltration process performance variables before coupling it to the bioreactor, a series of experiments were carried out using a 10,000 MWCO tubular ceramic membrane module. The variables studied were the bioreactor slurry permeation characteristics, such as, the permeate flux, VFA and the nutrient removal rates as a function of applied transmembrane pressure, fluid recirculation velocity, suspended matter concentration, and process operating time. Results indicate that the permeate flux, VFA and nutrients removal rates are directly proportional to the fluid recirculation velocity in the range between 0.6 to 1.0 m/s, applied pressure when these are low than 1.5 bar, and inversely proportional to the total suspended solids concentration in the range between 23,466 to 34,880. At applied pressure higher than 1.5 bar the flux is not more linearly dependent due to concentration polarization and fouling effects over the membrange surface. It was also found that the permeate flux declines rapidly during the first 5 to 8 hours, and then levels off with a diminishing rate of flux decay.

Optimisation of Noosa BNR plant to improve performance and reduce operating costs.

PubMed

Thomas, M; Wright, P; Blackall, L; Urbain, V; Keller, J

2003-01-01

Noosa WWTP is publicly owned and privately operated by Australian Water Services. The process includes primary sedimentation, raw sludge fermentation, biological nutrient removal (BNR), sand filtration and ultraviolet (UV) disinfection. An innovative feature of the plant is the supplementary carbon dosing facility to avoid the use of metal salts (alum or ferric) for phosphorus removal. The average flow treated during 2000 was 9.0 ML/d. The annual 50 percentile effluent quality requirements for nutrients are total N < 5 mg/L and total P < 1 mg/L. The objectives of this project were to: determine the cause of variability in phosphorus removal; develop a strategy to control the variability in phosphorus removal; and minimise the operating cost of supplementary carbon dosing while achieving the effluent quality requirements. An investigation of chemical and microbiological parameters was implemented and it was concluded that there were several factors causing variability in phosphorus removal, rather than a single cause. The following four major causes were identified, and the control strategies that were adopted resulted in the plant achieving annual 50 percentile effluent total P = 0.37 mg/L and total N = 3.0 mg/L during 2001. First, phosphorus removal was limited by the available VFA supply due to consumption of VFA by other organisms competing with phosphate accumulating organisms (PAO), and due to diurnal variations in the sewage VFA and phosphate concentrations. Therefore, supplementary carbon dosing was essential to make allowance for competing reactions. Second, increasing the fermenter VFA yield via supplementary carbon dosing with molasses was found to be an effective and economic way of ensuring reliable phosphorus removal. Third, nitrate in the RAS resulted in consumption of VFA by denitrifying bacteria, particularly with process configurations where the RAS was recycled directly into the anaerobic zone. Incorporating a RAS denitrification zone into the process rectified this problem. Finally, glycogen accumulating organisms (GAO) were observed in BNR sludge samples, and consumption of VFA by GAO appeared to cause decreased phosphorus removal. Better phosphorus removal was obtained using VFA derived from the fermenter than dosing an equivalent amount of acetic acid. It was hypothesized that GAO have a competitive advantage to use acetate and PAO have a competitive advantage to use propionate, butyrate or some other soluble COD compound in the fermenter effluent. Contrary to popular belief, acetate may not be the optimum VFA for biological phosphorus removal. The competition between PAO and GAO for different VFA species under anaerobic conditions requires further investigation in order to control the growth of GAO and thereby improve reliability of biological phosphorus removal processes.

The effects of a ration change from a total mixed ration to pasture on rumen fermentation, volatile fatty acid absorption characteristics, and morphology of dairy cows.

PubMed

Schären, M; Seyfang, G M; Steingass, H; Dieho, K; Dijkstra, J; Hüther, L; Frahm, J; Beineke, A; von Soosten, D; Meyer, U; Breves, G; Dänicke, S

2016-05-01

To investigate the effect of the change from a concentrate and silage-based ration (total mixed ration, TMR) to a pasture-based ration, a 10-wk trial (wk 1-10) was performed, including 10 rumen- and duodenum-fistulated German Holstein dairy cows (182±24 d in milk, 23.5±3.5kg of milk/d; mean ± standard deviation). The cows were divided in either a pasture group (PG, n=5) or a confinement group (CG, n=5). The CG stayed on a TMR-based ration (35% corn silage, 35% grass silage, 30% concentrate; dry matter basis), whereas the PG was gradually transitioned from a TMR to a pasture-based ration (wk 1: TMR only; wk 2: 3 h/d on pasture wk 3 and 4: 12 h/d on pasture wk 5-10: pasture only). Ruminal pH, volatile fatty acids (VFA), NH3-N, and lipopolysaccharide (LPS) concentrations were measured in rumen fluid samples collected medially and ventrally on a weekly basis. Ruminal pH was continuously recorded during 1 to 4 consecutive days each week using ruminal pH measuring devices. In wk 1, 5, and 10, rumen contents were evacuated and weighed, papillae were collected from 3 locations in the rumen, and subsequently a VFA absorption test was performed. In the PG, mean rumen pH and molar acetate proportions decreased, and molar butyrate proportions increased continuously over the course of the trial, which can most likely be ascribed to an increased intake of rapidly fermentable carbohydrates. During the first weeks on a full grazing ration (wk 5-7), variation of rumen pH decreased, and in wk 5 a lower rumen content, papillae surface area, and potential for VFA absorption were observed. In wk 8 to 10, variation of rumen pH and total VFA concentrations increased again, and acetate/propionate ratio decreased. In wk-10 rumen content, papillae area and VFA absorption characteristics similar to initial levels were observed. Although continuous rumen pH assessments and LPS concentrations did not reveal an increased risk for subacute rumen acidosis (SARA) during the adaption period, histopathology of rumen papillae and potential for VFA absorption indicated a possible risk for rumen health. An increased risk for SARA was observed in wk 9 and 10 in the PG, but rumen LPS concentrations and histopathology were not adversely affected. Results of the present study suggest that after behavioral and metabolic adaptation to the transition from a TMR to a pasture-based ration, no adverse effects on rumen morphology and absorption capacity occurred, although rumen pH after adaptation to pasture indicated increased risk of SARA. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The inhibitory effect of bovine rumen fluid on Salmonella typhimurium.

PubMed

Chambers, P G; Lysons, R J

1979-05-01

The possible fate of Salmonella typhimurium in the rumen was investigated by monitoring rumen volatile fatty acids (VFA), lactate concentrations and pH over periods which included regular feeding and 48 h starvation. Preparations were made containing 50 per cent rumen fluid from the cow or VFA solutions, and then inoculated with S typhimurium. Viable counts before and after incubation for 24 h at 37 degrees C were compared. Incubation in broths with high concentrations of VFA and low pH resulted in a marked decrease in salmonella numbers, while lower VFA concentrations had little or no inhibitory effect on growth.

Recovery of Volatile Fatty Acids from Fermented Wastewater by Adsorption

PubMed Central

2017-01-01

Separation of volatile fatty acids (VFAs) from fermented wastewater is challenging, due to low VFA concentrations in mineral-rich streams. As a result, separation capacity and selectivity with traditional solvents and adsorbents are both compromised. In this study, using a complex artificial model solution mimicking real fermented wastewaters, it is shown that a simple and robust adsorption-based separation technique can retain a remarkable capacity and selectivity for VFAs. Four types of polystyrene-divinylbenzene-based resins (primary, secondary, and tertiary amine-functionalized, and nonfunctionalized) were examined as the adsorbents. The presence of chloride, sulfate, and phosphate salts resulted in coadsorption of their acidic forms HCl, H2SO4, and H3PO4 on amine-functionalized adsorbents, and severely reduced the VFA capacity. With the nonfunctionalized adsorbent, almost no mineral acid coadsorption was observed. This together with a high total VFA capacity of up to 76 g/kg in equilibrium with the model solution containing a total VFA concentration of 1 wt % resulted in a very high selectivity for the VFAs. Nitrogen-stripping with various temperature profiles was applied to regenerate the adsorbent, and study the potential for fractionation of the VFAs during regeneration. Butyric acid (HBu) was obtained in mole fractions of up to 0.8 using a stepwise increase in the stripping temperature from 25 °C via 120 to 200 °C. During four successive adsorption–regeneration cycles, no reduction in the adsorption capacity was observed. PMID:28989827

Electrolytic extraction drives volatile fatty acid chain elongation through lactic acid and replaces chemical pH control in thin stillage fermentation.

PubMed

Andersen, Stephen J; Candry, Pieter; Basadre, Thais; Khor, Way Cern; Roume, Hugo; Hernandez-Sanabria, Emma; Coma, Marta; Rabaey, Korneel

2015-01-01

Volatile fatty acids (VFA) are building blocks for the chemical industry. Sustainable, biological production is constrained by production and recovery costs, including the need for intensive pH correction. Membrane electrolysis has been developed as an in situ extraction technology tailored to the direct recovery of VFA from fermentation while stabilizing acidogenesis without caustic addition. A current applied across an anion exchange membrane reduces the fermentation broth (catholyte, water reduction: H2O + e(-) → ½ H2 + OH(-)) and drives carboxylate ions into a clean, concentrated VFA stream (anolyte, water oxidation: H2O → 2e(-) + 2 H(+) + O2). In this study, we fermented thin stillage to generate a mixed VFA extract without chemical pH control. Membrane electrolysis (0.1 A, 3.22 ± 0.60 V) extracted 28 ± 6 % of carboxylates generated per day (on a carbon basis) and completely replaced caustic control of pH, with no impact on the total carboxylate production amount or rate. Hydrogen generated from the applied current shifted the fermentation outcome from predominantly C2 and C3 VFA (64 ± 3 % of the total VFA present in the control) to majority of C4 to C6 (70 ± 12 % in the experiment), with identical proportions in the VFA acid extract. A strain related to Megasphaera elsdenii (maximum abundance of 57 %), a bacteria capable of producing mid-chain VFA at a high rate, was enriched by the applied current, alongside a stable community of Lactobacillus spp. (10 %), enabling chain elongation of VFA through lactic acid. A conversion of 30 ± 5 % VFA produced per sCOD fed (60 ± 10 % of the reactive fraction) was achieved, with a 50 ± 6 % reduction in suspended solids likely by electro-coagulation. VFA can be extracted directly from a fermentation broth by membrane electrolysis. The electrolytic water reduction products are utilized in the fermentation: OH(-) is used for pH control without added chemicals, and H2 is metabolized by species such as Megasphaera elsdenii to produce greater value, more reduced VFA. Electro-fermentation displays promise for generating added value chemical co-products from biorefinery sidestreams and wastes.

Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland

PubMed Central

Glombitza, Clemens; Jaussi, Marion; Røy, Hans; Seidenkrantz, Marit-Solveig; Lomstein, Bente A.; Jørgensen, Bo B.

2015-01-01

Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent continental shelf in the NE Labrador Sea. VFA porewater concentrations were measured by a new two-dimensional ion chromatography-mass spectrometry method that enabled the direct analysis of VFAs without sample pretreatment. VFA concentrations were low and surprisingly constant (4–6 μmol L−1 for formate and acetate, and 0.5 μmol L−1 for propionate) throughout the sulfate reduction zone. Hence, VFAs are turned over while maintaining a stable concentration that is suggested to be under a strong microbial control. Estimated mean diffusion times of acetate between neighboring cells were <1 s, whereas VFA turnover times increased from several hours at the sediment surface to several years at the bottom of the sulfate reduction zone. Thus, diffusion was not limiting the VFA turnover. Despite constant VFA concentrations, the Gibbs energies (ΔGr) of VFA-dependent sulfate reduction decreased downcore, from −28 to −16 kJ (mol formate)−1, −68 to −31 kJ (mol acetate)−1, and −124 to −65 kJ (mol propionate)−1. Thus, ΔGr is apparently not determining the in-situ VFA concentrations directly. However, at the bottom of the sulfate zone of the shelf station, acetoclastic sulfate reduction might operate at its energetic limit at ~ −30 kJ (mol acetate)−1. It is not clear what controls VFA concentrations in the porewater but cell physiological constraints such as energetic costs of VFA activation or uptake could be important. We suggest that such constraints control the substrate turnover and result in a minimum ΔGr that depends on cell physiology and is different for individual substrates. PMID:26379631

A modified two-point titration method for the determination of volatile fatty acids in anaerobic systems.

PubMed

Mu, Zhe-Xuan; He, Chuan-Shu; Jiang, Jian-Kai; Zhang, Jie; Yang, Hou-Yun; Mu, Yang

2018-08-01

The volatile fatty acids (VFA) concentration plays important roles in the rapid start-up and stable operation of anaerobic reactors. It's essential to develop a simple and accurate method to monitor the VFA concentration in the anaerobic systems. In present work, a modified two-point titration method was developed to determine the VFA concentration. The results show that VFA concentration in standard solutions estimated by the titration method coincided well with that measured by gas chromatograph, where all relative errors were lower than 5.5%. Compared with the phosphate, ammonium and sulfide subsystems, the effect of bicarbonate on the accuracy of the developed method was relatively significant. When the bicarbonate concentration varied from 0 to 8 mmol/L, the relative errors increased from 1.2% to 30% for VFA concentration at 1 mmol/L, but were within 2.0% for that at 5 mmol/L. In addition, the VFA composition affected the accuracy of the titration method to some extent. This developed titration method was further proved to be effective with practical effluents from a lab-scale anaerobic reactor under organic shock loadings and an unstable full-scale anaerobic reactor. Copyright © 2018 Elsevier Ltd. All rights reserved.

The one-stage autothermal thermophilic aerobic digestion for sewage sludge treatment: stabilization process and mechanism.

PubMed

Liu, Shugen; Zhu, Nanwen; Li, Loretta Y

2012-01-01

Batch experiment was carried out in a simulated thermophilic aerobic digester to investigate the digestion process of one-stage autothermal thermophilic aerobic digester and to explore the sludge stabilization mechanism. Volatile solids removal was 38.4% at 408 h and 45.0% at 552 h. Chemical oxidation demand, total nitrogen, and ammonia nitrogen in supernatant increased rapidly up to 168 h, and all of them fluctuated moderately after 360 h. Volatile fatty acid (VFA) accumulated rapidly up to 24 to 168 h, then declined sharply, reaching a low concentration after 312 h. Propionic, iso-valeric, and iso-butyric acids, in addition to acetic acids, were also the major components of VFA. As the biochemical metabolic process was inhibited under oxygen-deficiency condition, the digestion system can produce acetic, propionic, butyric acids and other VFA constituents to meet the demand for NAD(+) and maximize ATP generation. The ORP affected the VFA production and depletion as well as sulfate levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

pH-adjustment strategy for volatile fatty acid production from high-strength wastewater for biological nutrient removal.

PubMed

Xie, Li; Liu, Hui; Chen, Yin-Guang; Zhou, Qi

2014-01-01

Volatile fatty acid (VFA) production from three types of high-strength organic wastewater (cassava thin stillage, starch wastewater and yellow-wine processing wastewater) were compared. The results showed that cassava thin stillage was the most suitable substrate, based on its high specific VFA production (0.68 g chemical oxygen demand (COD)/g initial soluble chemical oxygen demand (SCOD)) and yield (0.72 g COD/g SCOD) as well as low nutrient content in the substrate and fermented liquid. The acid fermented cassava thin stillage was evaluated and compared with sodium acetate in a sequencing batch reactor system. Total nitrogen removal efficiency was higher with fermented cassava thin stillage than with the sodium acetate. The effects of pH and a pH-adjustment strategy on VFA production and composition were determined using cassava thin stillage. At an initial pH range of 7-11, a relatively high VFA concentration of about 9 g COD/L was obtained. The specific VFA production (g COD/g initial SCOD) increased from 0.27 to 0.47 to 0.67 at pH 8 and from 0.26 to 0.68 to 0.81 at pH 9 (initial pH, interval pH, and constant pH adjustment, respectively). The dominant VFA species changed significantly with the increasing frequency of the pH adjustment. Further studies will examine the metabolic pathways responsible for VFA composition.

Build-up and impact of volatile fatty acids on E. coli and A. lumbricoides during co-digestion of urine diverting dehydrating toilet (UDDT-F) faeces.

PubMed

Riungu, Joy; Ronteltap, Mariska; van Lier, Jules B

2018-06-01

This study examined the potential of Escherichia coli (E. coli) and Ascaris lumbricoides (A. lumbricoides) eggs inactivation in faecal matter coming from urine diverting dehydrating toilets (UDDT-F) by applying high concentrations of volatile fatty acids (VFAs) during anaerobic stabilization. The impact of individual VFAs on E. coli and A. lumbricoides eggs inactivation in UDDT-F was assessed by applying various concentrations of store-bought acetate, propionate and butyrate. High VFA concentrations were also obtained by performing co-digestion of UDDT-F with organic market waste (OMW) using various mixing ratios. All experiments were performed under anaerobic conditions in laboratory scale batch assays at 35±1 °C. A correlation was observed between E. coli log inactivation and VFA concentration. Store bought VFA spiked UDDT-F substrates achieved E. coli inactivation up to 4.7 log units/day compared to UDDT-F control sample that achieved 0.6 log units/day. In co-digesting UDDT-F and organic market waste (OMW), a ND-VFA concentration of 4800-6000 mg/L was needed to achieve E. coli log inactivation to below detectable levels and complete A. lumbricoides egg inactivation in less than four days. E. coli and A. lumbricoides egg inactivation was found to be related to the concentration of non-dissociated VFA (ND-VFA), increasing with an increase in the OMW fraction in the feed substrate. Highest ND-VFA concentration of 6500 mg/L was obtained at a UDDT-F:OMW ratio 1:1, below which there was a decline, attributed to product inhibition of acidogenic bacteria. Results of our present research showed the potential for E. coli and A. lumbricoides inactivation from UDDT-F up to WHO standards by allowing VFA build-up during anaerobic stabilization of faecal matter. Copyright © 2018. Published by Elsevier Ltd.

Postprandial kinetics of some biotic and abiotic characteristics of the gastric ecosystem of horses fed a pelleted concentrate meal.

PubMed

Varloud, M; Fonty, G; Roussel, A; Guyonvarch, A; Julliand, V

2007-10-01

Our knowledge of the microflora of the stomach of the horse is still limited, although some data indicate its important role in nutrition. The objective of this experiment was to investigate the microbial and biochemical profiles in the stomach of the horse and to quantify the disappearance of dietary starch. Total anaerobic bacteria, lactate-utilizing bacteria, lactobacilli, and streptococci were determined, and biochemical characteristics (pH, and DM, D- and L-lactate, D-glucose, NH3, and VFA concentrations) were measured in chyme collected from 4 horses by naso-gastric intubation aided by endoscopy, at 30 min before and 60, 120, and 210 min after the meal. The total anaerobic population exhibited a linear increase (5.54 to 6.98 log10 cfu/mL; P = 0.018) within the first postprandial hour and reached 8.32 log10 cfu/mL at 210 min after the meal. The concentrations of lactobacilli, streptococci, and lactate-utilizing bacteria in the stomach contents were 5.52, 4.82, and 6.95 log10 cfu/mL, respectively. Lactate concentration increased linearly from 0.25 mmol/L before the meal to 7.98 mmol/L at the last collection point (P = 0.013). This increase was mostly due to L-lactate accumulation. The VFA concentration increased linearly (P = 0.002) during the postprandial period from 1.96 to 8.17 mmol/L. Acetate represented, on average, 78 mol/100 mol of total VFA. The average concentration of NH3 in the stomach content was 2.48 mmol/L. Dietary starch disappearance did not respond during the post-prandial period and was not consistent with previous findings. These in vivo data provide complementary information on the postprandial microbial and biochemical kinetics in the stomachs of horses and confirm its abundant microbial colonization.

The Associations Between Smoking Habits and Serum Triglyceride or Hemoglobin A1c Levels Differ According to Visceral Fat Accumulation.

PubMed

Koda, Michiko; Kitamura, Itsuko; Okura, Tomohiro; Otsuka, Rei; Ando, Fujiko; Shimokata, Hiroshi

2016-01-01

Whether smokers and former smokers have worse lipid profiles or glucose levels than non-smokers remains unclear. The subjects were 1152 Japanese males aged 42 to 81 years. The subjects were divided according to their smoking habits (nonsmokers, former smokers, and current smokers) and their visceral fat area (VFA) (<100 cm(2) and ≥100 cm(2)). The serum triglyceride (TG) levels of 835 males were assessed. In the VFA ≥100 cm(2) group, a significantly greater proportion of current smokers (47.3%) exhibited TG levels of ≥150 mg/dL compared with former smokers (36.4%) and non-smokers (18.8%). The difference in TG level distribution between former smokers and non-smokers was also significant. However, among the subjects with VFA of <100 cm(2), the TG levels of the three smoking habit groups did not differ. The serum hemoglobin A1c (HbA1c) levels of 877 males were also assessed. In the VFA <100 cm(2) group, significantly higher proportions of current smokers (17.9%) and former smokers (14.9%) demonstrated HbA1c levels of ≥5.6% compared with non-smokers (6.3%). In contrast, in the VFA ≥100 cm(2) group, significantly fewer former smokers displayed HbA1c levels of ≥5.6% compared with non-smokers and current smokers. Furthermore, the interaction between smoking habits and VFA was associated with the subjects' TG and HbA1c concentrations, and the associations of TG and HbA1c concentrations and smoking habits varied according to VFA. Both smoking habits and VFA exhibited associations with TG and HbA1c concentrations. The associations between smoking habits and these parameters differed according to VFA.

Transient feeding of a concentrate-rich diet increases the severity of subacute ruminal acidosis in dairy cattle.

PubMed

Pourazad, P; Khiaosa-Ard, R; Qumar, M; Wetzels, S U; Klevenhusen, F; Metzler-Zebeli, B U; Zebeli, Q

2016-02-01

The objective of this study was to investigate the effect of the pattern of concentrate-rich feeding on subacute ruminal acidosis (SARA), its severity, and the corresponding changes in VFA concentration. Eight rumen-cannulated Holstein cows were assigned to a 2 × 2 crossover design with 2 SARA challenge models and 2 experimental runs ( = 8 per treatment). Each run lasted for 40 d, consisting of a 6-d baseline, a 6-d gradual grain adaptation, and a 28-d SARA challenge period. The 2 SARA challenge models were transient (TRA) and persistent (PER) SARA. Initially, all cows were subjected to a forage-only diet (baseline) and gradually switched to 60% concentrate (DM basis). Then, cows in the PER model were continuously challenged for 28 d, whereas cows in the TRA model had a 7-d break from the SARA diet and were fed the forage-only diet after the first 7 d of SARA challenge. Thereafter, the TRA cows were rechallenged with the SARA diet. Wireless ruminal pH sensors were used to obtain ruminal pH profiles and temperature over the experimental period. For the determination of VFA, free ruminal liquid (FRL) and particle-associated ruminal liquid (PARL) were collected once for the baseline and twice (d 20 and 40 for the PER model) or 3 times (d 13, 30, and 40 for the TRA model) during SARA, each time at 0, 4, and 8 h after the morning feeding. Cows in both models experienced SARA albeit with day-to-day variation. From the start until the first 7-d SARA, cows of both models had similar pH profiles, but during the rechallenge, SARA was more severe in the TRA model than in the PER model based on lower daily mean ruminal pH (5.93 vs. 6.15; SEM 0.058) and double the amount of time at pH < 5.8 (497 vs. 278 min; SEM 68.61, < 0.05). Mean ruminal temperature was raised during SARA compared with the baseline (38.9 vs. 38.7°C; SEM 0.057, < 0.001). Concentrations of VFA increased with increasing time after feeding ( < 0.001). In general, SARA challenge (d 40 vs. the baseline), but not the challenge model, altered VFA concentrations and profile of both FRL and PARL by increasing the amounts of propionate and butyrate, whereas total VFA concentration was less affected. Proportions of VFA shifted over the duration of SARA challenge with more propionate but less acetate and butyrate proportions with advancing days of SARA challenge, leading to the values of the last SARA day being different from the earlier days ( < 0.05). In conclusion, the TRA condition led to the higher severity of SARA, but factors beyond feed intake and VFA alterations seemed to play a role.

Effect of trace minerals and starch on digestibility and rumen fermentation in diets for dairy heifers.

PubMed

Pino, F; Heinrichs, A J

2016-04-01

The objective of this study was to evaluate the effect of different forms of trace minerals (TM) and the use of different starch levels in dairy heifer diets on rumen fermentation and digestibility. Eight rumen cannulated dairy heifers (15.4 ± 0.8 mo of age and 438.31 ± 18.08 kg of body weight) were subjected to a split-plot, 4 × 4 Latin square design with 19-d periods: 15d of adaptation and 4d of sampling. The whole-plot factor was type of TM; organic as proteinates (OTM) or inorganic sulfates (ITM), and the subplot was starch level (3.54, 12.95, 22.25, and 31.73%). Total collection of feces and urine was completed on d 15 to 19 to determine digestibility and TM excretion. Rumen contents were sampled on d 18 to 19 at 0, 1, 2, 4, 8, 12, 16, 20, and 22 h after feeding to measure pH and volatile fatty acid (VFA) concentrations. Plasma samples were collected to evaluate TM concentrations and enzymatic activity for ceruloplasmin, glutathione peroxidase, and superoxide dismutase. Starch level affected pH, individual VFA concentrations, and nutrient excretion. Trace mineral intake was lower for OTM compared with ITM. No effect of TM form on dry matter digestibility was detected, but as level of starch increased, diet dry matter digestibility increased. Rumen pH was lower for diets with OTM, which is consistent with higher total VFA production and butyrate proportion observed for heifers fed OTM diets. These variables may be explained by the higher bioavailability of OTM and faster utilization and fermentation by rumen microorganisms. Heifers that consumed ITM had higher moisture in feces and higher urine excretion, which increased total manure production. Total excretion of TM was not different by treatment. Blood plasma mineral concentration was not different between treatments except for Mn, which was higher for OTM. Enzymatic activity was not affected by treatments. Mineral intake was reduced and blood mineral levels were not different, suggesting enhanced absorption of OTM compared with ITM. In conclusion, based on rumen pH, VFA production, and plasma TM concentration, OTM may be more ruminally bioavailable and absorbed to a greater extent than ITM. Also, TM form affected fecal moisture and urine excretion, suggesting that ITM may stimulate water intake. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Dietary marker effects on fecal microbial ecology, fecal VFA, nutrient digestibility coefficients, and growth performance in finishing pigs.

PubMed

Kerr, B J; Weber, T E; Ziemer, C J

2015-05-01

Use of indigestible markers such as Cr2O3, Fe2O3, and TiO2 are commonly used in animal studies to evaluate digesta rate of passage and nutrient digestibility. Yet, the potential impact of indigestible markers on fecal microbial ecology and subsequent VFA generation is not known. Two experiments utilizing a total of 72 individually fed finishing pigs were conducted to describe the impact of dietary markers on fecal microbial ecology, fecal ammonia and VFA concentrations, nutrient digestibility, and pig performance. All pigs were fed a common diet with no marker or with 0.5% Cr2O3, Fe2O3, or TiO2. In Exp. 1, after 33 d of feeding, fresh fecal samples were collected for evaluation of microbial ecology, fecal ammonia and VFA concentrations, and nutrient digestibility, along with measures of animal performance. No differences were noted in total microbes or bacterial counts in pig feces obtained from pigs fed the different dietary markers while Archaea counts were decreased (P = 0.07) in feces obtained from pigs fed the diet containing Fe2O 3compared to pigs fed the control diet. Feeding Cr2O3, Fe2O3, or TiO2 increased fecal bacterial richness (P = 0.03, 0.01, and 0.10; respectively) when compared to pigs fed diets containing no marker, but no dietary marker effects were noted on fecal microbial evenness or the Shannon-Wiener index. Analysis of denaturing gradient gel electrophoresis gels did not reveal band pattern alterations due to inclusion of dietary markers in pig diets. There was no effect of dietary marker on fecal DM, ammonia, or VFA concentrations. Pigs fed diets containing Cr2O3 had greater Ca, Cu, Fe, and P (P ≤ 0.02), but lower Ti ( P= 0.08) digestibility compared to pigs fed the control diet. Pigs fed diets containing Fe2O3 had greater Ca (P = 0.08) but lower Ti (P = 0.01) digestibility compared to pigs fed the control diet. Pigs fed diets containing TiO2 had greater Fe and Zn (P ≤ 0.09), but lower Ti ( P= 0.01) digestibility compared to pigs fed the control diet. In Exp. 2, no effect of dietary marker on pig performance was noted. Overall, the data indicate that the inclusion of Cr2O3, Fe2O3, or TiO2 as digestibility markers have little to no impact on microbial ecology, fecal ammonia or VFA concentrations, nutrient digestibility, or pig growth performance indicating they are suitable for use in digestion studies.

The effects of starch and rapidly degradable dry matter from concentrate on ruminal digestion in dairy cows fed corn silage-based diets with fixed forage proportion.

PubMed

Lechartier, C; Peyraud, J-L

2011-05-01

This study investigated the effects of the type (starch vs. nonstarch) and rate of ruminal degradation of carbohydrates from the concentrate on digestion in dairy cows fed corn silage-based diets. Six ruminally cannulated cows were assigned to 6 treatments in a 6 × 6 Latin square design. Treatments were arranged in a 3 × 2 factorial design. Two starch levels [25 and 41% dry matter (DM) for low starch (LS) and high starch (HS) diets, respectively] were obtained by replacing starch-rich feedstuffs by nonstarch feedstuffs. These starch levels were combined with slowly, moderately, and rapidly rumen-degradable feedstuffs to obtain 3 levels of rapidly degradable carbohydrates from concentrate (18, 23, and 28% DM). These levels were estimated from the DM disappearance of concentrate after 4h of in sacco incubation (CRDM). Wheat and corn grain were used as rapidly degradable and slowly degradable starch feedstuffs, respectively. Soybean hulls and citrus pulp were used as slowly degradable and rapidly degradable nonstarch feedstuffs, respectively. No interaction effect was found between dietary starch content and CRDM on pH range, volatile fatty acid (VFA) range, or VFA profile. Increasing CRDM led to a linear decrease in acetate-to-propionate ratio (from 2.7 to 2.1), and a linear increase in the pH and VFA ranges (from 0.86 to 1.12 pH units and from 34 to 56mM, respectively). Feeding HS diets decreased acetate-to-propionate ratio (2.6 vs. 2.0) and increased pH range (0.89 vs. 1.04 pH units), but had no effect on VFA range. Increasing CRDM linearly decreased mean ruminal pH in LS diets but linearly increased mean ruminal pH in HS diets. Fibrolytic activity was unaffected in LS diets but decreased strongly in HS diets (from 62 to 50%). These findings suggest that pH regulation differs on a short-term and on a longer-term basis. In the short-term, increasing CRDM increased the rate of VFA production, which may have been partly buffered under LS diets due to the higher cation exchange capacity of nonstarch feedstuffs compared with starch-rich feedstuffs. In the longer term, feeding starch reduced fibrolytic activity, which may have led to lower total VFA production and higher mean pH. The results of this experiment clearly show that both fermentative characteristics of the concentrate and dietary starch content should be taken into account when formulating diets to prevent subacute ruminal acidosis and to predict VFA profile. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Products derived from olive leaves and fruits can alter in vitro ruminal fermentation and methane production.

PubMed

Shakeri, Pirouz; Durmic, Zoey; Vadhanabhuti, Joy; Vercoe, Philip E

2017-03-01

The industrial processing of olive generates a high quantity of by-products. The objective of this study was to examine the effects of products derived from olive trees, i.e. leaves, fruits or kernels as a sole substrate (part A), and crude extract from leaves combined with a substrate (part B) on rumen microbial fermentation in an in vitro batch fermentation system. In this study, total gas production, methane production, and concentrations of volatile fatty acids (VFA) and ammonia in ruminal fluid were measured. In part A, in vitro fermentation of leaves or fruits yielded a gas and total VFA production that were comparable with control substrate, while most of them produced significantly less methane (up to 55.6%) when compared to control substrate. In part B, amongst leaf extracts, only addition of chloroform extract reduced methane production, which was also associated with a decrease (P < 0.01) in gas production. This effect was associated with a significant reduction (P < 0.01) in acetate to propionate ratio and ammonia production, but not in reduction in VFA concentrations. Olive leaf and olive leaf chloroform extract reduced ammonia production and increased the molar proportion of propionate in the rumen and can assist in developing novel feed additives for methane mitigation from the rumen. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Clorate Metabolism in Pure Cultures of E.Coli 0157:H7 Pretreated with Either Nitrate or Chlorate

USDA-ARS?s Scientific Manuscript database

Experiments were conducted to determine the effects of 5, 7.5, and 10 mM nitrate, and 5, 10, or 20 mM chlorate on total E. coli counts, chlorate metabolism, and volatile fatty acid (VFA) concentrations in anaerobic ruminal fluid cultures. Nitrate did not affect total E. coli counts (P = 0.05), chlor...

Impact of mash feeding versus pellets on propionic/butyric acid levels and on total load in the gastrointestinal tract of growing pigs.

PubMed

Longpré, J; Fairbrother, J M; Fravalo, P; Arsenault, J; LeBel, P; Laplante, B; Surprenant, C; Massé, D; Letellier, A

2016-03-01

Feed characteristics may influence the bacterial community composition and metabolic activities in the pig gastrointestinal tract, known to be associated with positive effects on the gut. Use of mash feed is associated with reduced excretion, but little is known of its effect on the population or of the mechanism of action. Our objectives were to assess the effect of feed texture combined with feed particle size on VFA profiles and levels, total count, and the presence of genes encoding virulence factors of pathogenic strains in the digestive tract along with their impact on pig performance of fattening pigs. Pigs ( = 840) on a commercial farm received mash or pellet diets of different particle sizes during the fattening period. Caecal and colon contents from 164 pigs were sampled at the slaughterhouse for enumeration of by quantitative PCR (qPCR) and for VFA quantification by capillary gas chromatography. The gene was used to enumerate total . Improved pig performances associated with pellet texture and a 500-μm size were observed. Caecal ( = 0.02) and colon ( < 0.01) propionic acid concentrations were lower for pigs receiving pellet rather than mash feed. Similarly, caecal ( = 0.01) and colon ( < 0.001) butyric acid concentrations were also lower for pigs receiving pellet rather than mash feed, as determined by capillary gas chromatography. Moreover, caecal ( = 0.03) and colon ( < 0.001) butyric acid concentrations were higher for pigs receiving a feed with a 1,250-μm particle size rather than a 500-μm particle size. On the other hand, total caecal and colon levels were higher for pigs receiving pellet feed than for those receiving mash feed. For total enumeration, caecal ( < 0.01) and colon ( < 0.01) gene copies were higher for pigs receiving pellet rather than mash feed. No effect of particle size on fatty acid concentrations or on numbers was observed. Virulence gene quantification revealed no trend. Taken together, results showed that mash feed is associated with lower growth performance but with favorable intestinal changes linked to VFA levels and reduction in the intestine.

Acidogenic digestion of food waste in a thermophilic leach bed reactor: Effect of pH and leachate recirculation rate on hydrolysis and volatile fatty acid production.

PubMed

Hussain, Abid; Filiatrault, Mélissa; Guiot, Serge R

2017-12-01

The effect of pH control (4, 5, 6, 7) on volatile fatty acids (VFA) production from food waste was investigated in a leach bed reactor (LBR) operated at 50°C. Stabilisation of pH at 7 resulted in hydrolysis yield of 530g soluble chemical oxygen demand (sCOD)/kg total volatile solids (TVS) added and VFA yield of 247gCOD/kg TVS added, which were highest among all pH tested. Butyric acid dominated the VFA mix (49-54%) at pH of 7 and 6, while acetate composed the primary VFA (41-56%) at pH of 4 and 5. A metabolic shift towards lactic acid production was observed at pH of 5. Improving leachate recirculation rate further improved the hydrolysis and degradation efficiency by 10-16% and the acidification yield to 340gCOD/kgTVS added. The butyric acid concentration of 16.8g/L obtained at neutral pH conditions is among the highest reported in literature. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Changes in in vitro gas and methane production from rumen fluid from dairy cows during adaptation to feed additives in vivo.

PubMed

Klop, G; van Laar-van Schuppen, S; Pellikaan, W F; Hendriks, W H; Bannink, A; Dijkstra, J

2017-04-01

The adaptation of dairy cows to methane (CH4)-mitigating feed additives was evaluated using the in vitro gas production (GP) technique. Nine rumen-fistulated lactating Holstein cows were grouped into three blocks and within blocks randomly assigned to one of three experimental diets: Control (CON; no feed additive), Agolin Ruminant® (AR; 0.05 g/kg dry matter (DM)) or lauric acid (LA; 30 g/kg DM). Total mixed rations composed of maize silage, grass silage and concentrate were fed in a 40 : 30 : 30 ratio on DM basis. Rumen fluid was collected from each cow at days -4, 1, 4, 8, 15 and 22 relative to the introduction of the additives in the diets. On each of these days, a 48-h GP experiment was performed in which rumen fluid from each individual donor cow was incubated with each of the three substrates that reflected the treatment diets offered to the cows. DM intake was on average 19.8, 20.1 and 16.2 kg/day with an average fat- and protein-corrected milk production of 30.7, 31.7 and 26.2 kg/day with diet CON, AR and LA, respectively. In general, feed additives in the donor cow diet had a larger effect on gas and CH4 production than the same additives in the incubation substrate. Incubation substrate affected asymptotic GP, half-time of asymptotic CH4 production, total volatile fatty acid (VFA) concentration, molar proportions of propionate and butyrate and degradation of organic matter (OMD), but did not affect CH4 production. No substrate×day interactions were observed. A significant diet×day interaction was observed for in vitro gas and CH4 production, total VFA concentration, molar proportions of VFA and OMD. From day 4 onwards, the LA diet persistently reduced gas and CH4 production, total VFA concentration, acetate molar proportion and OMD, and increased propionate molar proportion. In vitro CH4 production was reduced by the AR diet on day 8, but not on days 15 and 22. In line with these findings, the molar proportion of propionate in fermentation fluid was greater, and that of acetate smaller, for the AR diet than for the CON diet on day 8, but not on days 15 and 22. Overall, the data indicate a short-term effect of AR on CH4 production, whereas the CH4-mitigating effect of LA persisted.

Postprandial portal fluxes of essential amino acids, volatile fatty acids, and urea-nitrogen in growing pigs fed a high-fiber diet supplemented with a multi-enzyme cocktail.

PubMed

Agyekum, A K; Kiarie, E; Walsh, M C; Nyachoti, C M

2016-09-01

The present study investigated the effects of adding a multi-enzyme cocktail (MC) to a high-fiber diet on net portal-drained viscera (PDV) fluxes of essential AA (EAA), volatile fatty acids (VFA), and blood urea-N (BUN) in growing pigs. Five female pigs (22.8 ± 1.6 kg BW), with catheters in the portal vein, ileal vein, and carotid artery, were fed 3 isocaloric-nitrogenous diets at 4% of their BW once daily at 0900 h for 7 d in a replicated 3 × 3 Latin square design. The diets contained corn and soybean meal with 0% (control) or 30% distillers' dried grains with solubles (DDGS; HF) produced from a 1:1 mixture of wheat and corn. The third diet was supplemented with MC in addition to the 30% DDGS (HF + MC). The MC supplied (analyzed values) 5,397 U of xylanase, 162 U of β-glucanase, and 2,000 U of protease and guaranteed minimum activities of 1,000 U of α-amylase and 25 U of pectinase per kg of diet. On d 7, para-amino hippuric acid was infused into the ileal vein (to measure flow rate), and blood was sampled from the portal vein and carotid artery for 7 h after feeding to assay EAA, urea-N, and VFA. Portal absorption of nutrients was derived by multiplying the porto-arterial plasma concentration differences by portal vein blood flow. Diet had no effect on postprandial portal vein plasma flow rate and net BUN flux, but portal BUN tended to be lower ( = 0.070) and arterial BUN was lower ( 0.05) over the 7 h in pigs fed control. Postprandial portal Arg, Ile, Leu, Trp, and Val or net fluxes were lower ( 0.05) in HF-fed pigs from 30 to 240 min than control-fed pigs and MC supplementation tended (0.05 ≤ ≤ 0.10) to or improved ( 0.05) portal appearances of those AA, but not their fluxes. Control-fed pigs had higher ( 0.05) net portal fluxes of most EAA and pigs fed HF + MC had higher ( 0.05) Lys, and similar Met and Phe net portal fluxes were compared with control-fed pigs. Portal VFA was not affected by diet. However, total portal VFA flux was lower ( 0.05) in the HF-fed pigs than in the control pigs. The MC supplementation improved the total portal VFA flux, although it did not improve arterial VFA concentration relative to the HF diet. In conclusion, supplementing the HF diet with MC improved net portal appearance of some EAA and fluxes of total VFA, whereas fluxes of EAA did not change. The HF diet increased EAA demand by the PDV, but MC addition was not able to reduce this demand.

The Associations Between Smoking Habits and Serum Triglyceride or Hemoglobin A1c Levels Differ According to Visceral Fat Accumulation

PubMed Central

Koda, Michiko; Kitamura, Itsuko; Okura, Tomohiro; Otsuka, Rei; Ando, Fujiko; Shimokata, Hiroshi

2016-01-01

Background Whether smokers and former smokers have worse lipid profiles or glucose levels than non-smokers remains unclear. Methods The subjects were 1152 Japanese males aged 42 to 81 years. The subjects were divided according to their smoking habits (nonsmokers, former smokers, and current smokers) and their visceral fat area (VFA) (<100 cm2 and ≥100 cm2). Results The serum triglyceride (TG) levels of 835 males were assessed. In the VFA ≥100 cm2 group, a significantly greater proportion of current smokers (47.3%) exhibited TG levels of ≥150 mg/dL compared with former smokers (36.4%) and non-smokers (18.8%). The difference in TG level distribution between former smokers and non-smokers was also significant. However, among the subjects with VFA of <100 cm2, the TG levels of the three smoking habit groups did not differ. The serum hemoglobin A1c (HbA1c) levels of 877 males were also assessed. In the VFA <100 cm2 group, significantly higher proportions of current smokers (17.9%) and former smokers (14.9%) demonstrated HbA1c levels of ≥5.6% compared with non-smokers (6.3%). In contrast, in the VFA ≥100 cm2 group, significantly fewer former smokers displayed HbA1c levels of ≥5.6% compared with non-smokers and current smokers. Furthermore, the interaction between smoking habits and VFA was associated with the subjects’ TG and HbA1c concentrations, and the associations of TG and HbA1c concentrations and smoking habits varied according to VFA. Conclusions Both smoking habits and VFA exhibited associations with TG and HbA1c concentrations. The associations between smoking habits and these parameters differed according to VFA. PMID:26616395

Ground Juniperus pinchotii and urea in supplements fed to Rambouillet ewe lambs Part 2: Ewe lamb rumen microbial communities.

PubMed

Ishaq, S L; Yeoman, C J; Whitney, T R

2017-10-01

This study evaluated effects of ground redberry juniper () and urea in dried distillers grains with solubles-based supplements fed to Rambouillet ewe lambs ( = 48) on rumen physiological parameters and bacterial diversity. In a randomized study (40 d), individually-penned lambs were fed ground sorghum-sudangrass hay and of 1 of 8 supplements (6 lambs/treatment; 533 g/d; as-fed basis) in a 4 × 2 factorial design with 4 concentrations of ground juniper (15%, 30%, 45%, or 60% of DM) and 2 levels of urea (1% or 3% of DM). Increasing juniper resulted in minor changes in microbial β-diversity (PERMANOVA, pseudo F = 1.33, = 0.04); however, concentrations of urea did not show detectable broad-scale differences at phylum, family, or genus levels according to ANOSIM ( > 0.05), AMOVA ( > 0.10), and PERMANOVA ( > 0.05). Linear discriminant analysis indicated some genera were specific to certain dietary treatments ( < 0.05), though none of these genera were present in high abundance; high concentrations of juniper were associated with and , low concentrations of urea were associated with , and high concentrations of urea were associated with and . were decreased by juniper and urea. , , and increased with juniper and were positively correlated (Spearman's, < 0.05) with each other but not to rumen factors, suggesting a symbiotic interaction. Overall, there was not a juniper × urea interaction for total VFA, VFA by concentration or percent total, pH, or ammonia ( 0.29). When considering only percent inclusion of juniper, ruminal pH and proportion of acetic acid linearly increased ( < 0.001) and percentage of butyric acid linearly decreased ( = 0.009). Lamb ADG and G:F were positively correlated with (Spearman's, < 0.05) and negatively correlated with Synergistaceae, the BS5 group, and Lentisphaerae. Firmicutes were negatively correlated with serum urea nitrogen, ammonia, total VFA, total acetate, and total propionate. Overall, modest differences in bacterial diversity among treatments occurred in the abundance or evenness of several OTUs, but there was not a significant difference in OTU richness. As diversity was largely unchanged, the reduction in ADG and lower-end BW was likely due t* reduced DMI rather than a reduction in microbial fermentative ability.

Rumen microbial changes in cattle fed diets with or without salinomycin.

PubMed

Olumeyan, D B; Nagaraja, T G; Miller, G W; Frey, R A; Boyer, J E

1986-02-01

Four rumen-fistulated steers, randomly assigned to two groups (control and salinomycin fed) were used to monitor the changes in rumen microbial populations and volatile fatty acids (VFA) concentrations associated with feeding salinomycin (0.22 mg X kg-1 X day-1). Steers were adapted to an alfalfa hay and grain (80:20) diet before supplementing the diet with salinomycin, and then the diet was changed to 50:50 and 20:80 ratios of alfalfa hay to grain at 2-week intervals. Rumen samples for total and selective enumeration of anaerobic bacteria. VFA analysis, and enumeration of protozoa were collected during the 80:20 alfalfa hay-to-grain diet before salinomycin feeding, and during the 80:20, 50:50, and 20:80 hay-to-grain diets with salinomycin. At each sampling period, rumen samples were collected at 3 h after feeding on three consecutive days. Salinomycin feeding had no effect on rumen pH and total VFA concentration. The acetate-to-propionate ratio was significantly lower in salinomycin-fed steers than in the control. The molar proportion of butyrate increased in both control and salinomycin-fed steers. Total anaerobic bacterial counts were lower in salinomycin-fed steers than in the control steers after 8 weeks of salinomycin feeding. Salinomycin-resistant bacteria increased from 7.6 to 15.6% in salinomycin-fed steers but remained unchanged in control steers. Salinomycin had no effect on cellulolytic and lactate-utilizing bacteria, but the proportion of amylolytic bacteria was higher in salinomycin-fed steers than in control steers. The total number of protozoa decreased initially in salinomycin-fed steers. The initial reduction was due to reduced numbers of Entodinium species. Holotrichs were unaffected by salinomycin feeding.

Methane Production of Different Forages in In vitro Ruminal Fermentation

PubMed Central

Meale, S. J.; Chaves, A. V.; Baah, J.; McAllister, T. A.

2012-01-01

An in vitro rumen batch culture study was completed to compare effects of common grasses, leguminous shrubs and non-leguminous shrubs used for livestock grazing in Australia and Ghana on CH4 production and fermentation characteristics. Grass species included Andropodon gayanus, Brachiaria ruziziensis and Pennisetum purpureum. Leguminous shrub species included Cajanus cajan, Cratylia argentea, Gliricidia sepium, Leucaena leucocephala and Stylosanthes guianensis and non-leguminous shrub species included Annona senegalensis, Moringa oleifera, Securinega virosa and Vitellaria paradoxa. Leaves were harvested, dried at 55°C and ground through a 1 mm screen. Serum bottles containing 500 mg of forage, modified McDougall’s buffer and rumen fluid were incubated under anaerobic conditions at 39°C for 24 h. Samples of each forage type were removed after 0, 2, 6, 12 and 24 h of incubation for determination of cumulative gas production. Methane production, ammonia concentration and proportions of VFA were measured at 24 h. Concentration of aNDF (g/kg DM) ranged from 671 to 713 (grasses), 377 to 590 (leguminous shrubs) and 288 to 517 (non-leguminous shrubs). After 24 h of in vitro incubation, cumulative gas, CH4 production, ammonia concentration, proportion of propionate in VFA and IVDMD differed (p<0.05) within each forage type. B. ruziziensis and G. sepium produced the highest cumulative gas, IVDMD, total VFA, proportion of propionate in VFA and the lowest A:P ratios within their forage types. Consequently, these two species produced moderate CH4 emissions without compromising digestion. Grazing of these two species may be a strategy to reduce CH4 emissions however further assessment in in vivo trials and at different stages of maturity is recommended. PMID:25049482

Effects of organic loading rate on hydrogen and volatile fatty acid production and microbial community during acidogenic hydrogenesis in a continuous stirred tank reactor using molasses wastewater.

PubMed

Yun, J; Cho, K-S

2016-12-01

Microbial community associated with hydrogen production and volatile fatty acids (VFAs) accumulation was characterized in acidogenic hydrogenesis using molasses wastewater as a feedstock. Hydrogen and VFAs production were measured under an organic loading rate (OLR) from 19 to 35 g-COD l -1  day -1 . The active microbial community was analysed using RNA-based massively parallel sequencing technique, and their correlation patterns were analysed using networking analysis. The continuous stirred tank reactor achieved stable hydrogen production at different OLR conditions, and the maximum hydrogen production rate (HPR) was 1·02 L-H 2  l -1  day -1 at 31·0 g-COD l -1  day -1 . Butyrate (50%) and acetate (38%) positively increased with increase in OLR. Total VFA production stayed around 7135 mg l -1 during the operation period. Although Clostridiales and Lactobacillales were relatively abundant, the HPR was positively associated with Pseudomonadaceae and Micrococcineae. Total VFA and acetate, butyrate and propionate concentrations were positively correlated with lactic acid bacteria (LAB) such as Bacillales, Sporolactobacillus and Lactobacillus. The close relationship between Pseudomonadaceae and Micrococcineae, and LAB play important roles for stable hydrogen and VFA production from molasses wastewater. Microbial information on hydrogen and VFA production can be useful to design and operate for acidogenic hydrogenesis using high strength molasses wastewater. © 2016 The Society for Applied Microbiology.

Evaluation of the 5 and 8 pH point titration methods for monitoring anaerobic digesters treating solid waste.

PubMed

Vannecke, T P W; Lampens, D R A; Ekama, G A; Volcke, E I P

2015-01-01

Simple titration methods certainly deserve consideration for on-site routine monitoring of volatile fatty acid (VFA) concentration and alkalinity during anaerobic digestion (AD), because of their simplicity, speed and cost-effectiveness. In this study, the 5 and 8 pH point titration methods for measuring the VFA concentration and carbonate system alkalinity (H2CO3*-alkalinity) were assessed and compared. For this purpose, synthetic solutions with known H2CO3*-alkalinity and VFA concentration as well as samples from anaerobic digesters treating three different kind of solid wastes were analysed. The results of these two related titration methods were verified with photometric and high-pressure liquid chromatography measurements. It was shown that photometric measurements lead to overestimations of the VFA concentration in the case of coloured samples. In contrast, the 5 pH point titration method provides an accurate estimation of the VFA concentration, clearly corresponding with the true value. Concerning the H2CO3*-alkalinity, the most accurate and precise estimations, showing very similar results for repeated measurements, were obtained using the 8 pH point titration. Overall, it was concluded that the 5 pH point titration method is the preferred method for the practical monitoring of AD of solid wastes due to its robustness, cost efficiency and user-friendliness.

Effects of grain, fructose, and histidine on ruminal pH and fermentation products during an induced subacute acidosis protocol.

PubMed

Golder, H M; Celi, P; Rabiee, A R; Heuer, C; Bramley, E; Miller, D W; King, R; Lean, I J

2012-04-01

The effects of grain, fructose, and histidine on ruminal pH and fermentation products were studied in dairy cattle during an induced subacute acidosis protocol. Thirty Holstein heifers were randomly allocated to 5 treatment groups: (1) control (no grain); (2) grain [fed at a crushed triticale dry matter intake (DMI) of 1.2% of body weight (BW)]; (3) grain (0.8% of BW DMI)+fructose (0.4% of BW DMI); (4) grain (1.2% of BW DMI)+histidine (6 g/head); and (5) grain (0.8% of BW DMI)+fructose (0.4% of BW DMI)+histidine (6 g/head) in a partial factorial arrangement. Heifers were fed 1 kg of grain daily with ad libitum access to ryegrass silage and alfalfa hay for 10 d. Feed was withheld for 14 h before challenge day, on which heifers were fed 200 g of alfalfa hay and then the treatment diets immediately thereafter. Rumen samples were collected 5 min after diet ingestion, 60 min later, and at 3 subsequent 50-min intervals. Grain decreased ruminal pH and increased ammonia, total volatile fatty acid (VFA), acetate, butyrate, propionate, and valerate concentrations compared with controls. The addition of grain had no effect on ruminal D- and L-lactate concentrations. Fructose markedly decreased ruminal pH and markedly increased D- and L-lactate concentrations. Fructose increased total VFA and butyrate and decreased valerate concentrations. Although histidine did not have a marked effect on ruminal fermentation, increased concentrations of histamine were observed following feeding. This study demonstrates that the substitution of some grain for fructose can lower ruminal pH and increase VFA and lactate concentrations, warranting further investigation into the role of sugars on the risk of acidosis in dairy cattle. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The Concentrations of Rumen Fluid Volatile Fatty Acids and Ammonia, and Rumen Microbial Protein Production in Sheep Given Feed During the Day and Night Time

NASA Astrophysics Data System (ADS)

Gumilar, D. A. K. W.; Rianto, E.; Arifin, M.

2018-02-01

An experimental study was carried out to investigate the concentrations of volatile (VFA), ammonia and microbial protein production of rumen fluid in sheep given fedd during the day and at night. This study used 12 fat-tailed rams aged 12-18 months and weighed 24,12 ± 25 kg (CV = 10,51%). The rams were fed a complete feed containing 16.64% protein and 68,33% total digestible nutrients (TDN). The rams were allocated into a completely randomised design with 3 treatments and 4 replications. The treatments applied were: T1: day time feeding (6.00 hrs - 18.00 hrs); T2: night time feeding (18.00 hrs - 6.00 hrs); and T3: day and night time feedings (6.00 hrs - 6.00 hrs). The parameters observed were dry matter intake (DMI), rumen VFA concentration, rumen ammonia concentration, rumen rmicrobial protein production and the efficiency of rumen microbial protein production. The results showed that feeding time did not significantly affect (P>0.05) all the parameters observed. Dry matter intake, VFA concentration, ammonia concentration, the microbial protein production of rumen fluid and the efficiency of microbial protein production were 1,073g/d, 49.69 mmol; 4.77 mg N/100 ml, 12,111 g/d and 19.96 g per kg digestible organic matter intake (DOMI), respectively. It is concluded that feeding time did not affect DMI, condition of rumen fluid and rumen microbial protein production in sheep.

Discrepancies between leg-to-leg bioelectrical Impedance analysis and computerized tomography in abdominal visceral fat measurement.

PubMed

Lu, Hsueh-Kuan; Chen, Yu-Yawn; Yeh, Chinagwen; Chuang, Chih-Lin; Chiang, Li-Ming; Lai, Chung-Liang; Casebolt, Kevin M; Huang, Ai-Chun; Lin, Wen-Long; Hsieh, Kuen-Chang

2017-08-22

The aim of this study was to evaluate leg-to-leg bioelectrical impedance analysis (LBIA) using a four-contact electrode system for measuring abdominal visceral fat area (VFA). The present study recruited 381 (240 male and 141 female) Chinese participants to compare VFA measurements estimated by a standing LBIA system (VFALBIA) with computerized tomography (CT) scanned at the L4-L5 vertebrae (VFA CT ). The total mean body mass index (BMI) was 24.7 ± 4.2 kg/m 2 . Correlation analysis, regression analysis, Bland-Altman plot, and paired sample t-tests were used to analyze the accuracy of the VFA LBIA . For the total subjects, the regression line was VFA LBIA  = 0.698 VFA CT  + 29.521, (correlation coefficient (r) = 0.789, standard estimate of error (SEE) = 24.470 cm 2 , p < 0.001), Lin's correlation coefficient (CCC) was 0.785; and the limit of agreement (LOA; mean difference ±2 standard deviation) ranged from -43.950 to 67.951 cm 2 , LOA% (given as a percentage of mean value measured by the CT) was 48.2%. VFA LBIA and VFA CT showed significant difference (p < 0.001). Collectively, the current study indicates that LBIA has limited potential to accurately estimate visceral fat in a clinical setting.

[Effect of Ce3+ on volatile fatty acid concentrations during anaerobic granular sludge digestion].

PubMed

Liang, Rui; Xia, Qing; Ding, Li-Li; Shi, Xiao-Lei; Zhao, Ming-Yu; Ren, Hong-Qiang

2009-04-15

Batch experiments were conducted to investigate the effect of Ce3+ on volatile fatty acid(VFA) concentrations by anaerobic granular sludge digestion using D-Glucose and acetic sodium as substrate in the state of stabilization and restart-up. Results show that when the concentration of Ce3+ is lower than 1 mg/L, VFA concentration decreases, which suggests the transformation of butyric acid to acetic acid and acetic acid to methane is promoted. When the concentration of Ce3+ is 1-10 mg/L, the bacterial activity decreases and decomposition of the acetic acid and butyric acid becomes more difficult compared with the control. Adding Ce3+ brings little change in the constitution of VFA: 96% of VFA is acetic acid and butyric acid, while the propionic acid accounts for less than 3%. With the acetic sodium as the sole carbon and energy source, adding 0.05 mg/L Ce3+ could accelerate acetate degradation. After being conserved for 4 months, the activity of the Ce-containing anaerobic granular sludge is higher than that of the Ce-free sludge. The present of Ce contributes to the restart-up of anaerobic reactors.

Profile of Rumen Fermentation and Blood Urea Nitrogen Concentration of Kacang Goat Fed Total Mixed Ration Vs. Roughage

NASA Astrophysics Data System (ADS)

Adiwinarti, R.; Kustantinah; Budisatria, I. G. S.; Rusman; Indarto, E.

2018-02-01

Kacang goat is usually reared traditionally fed natural grass and having inferior performance. Many researches had been done to improve the performance. Total mixed ration (TMR) containing soybean meal (SBM) and fish meal (FM) could increase the performance of Kacang goat, but the profile of rumen fermentation has not been published. Therefore, this study investigated the profile of rumen fermentation and blood urea Nitrogen concentration (BUN) in Kacang goat fed natural grass (roughage) and TMR. Twelve yearling Kacang buck, 15.2-19.6 kg were arranged in completely randomized design. The treatments were NG (natural grass), FM (TMR containing FM), and SBM (TMR containing SBM). The TMR were formulated containing 15% crude protein and 56-58% TDN. Data were analyzed by one way ANOVA. Rumen pH 6 hours after feeding of NG (7.4) was higher (P<0.01) than that of FM (6.2) and SBM (6.4). This lowering pH of TMR was caused by increasing volatile fatty acids (VFA). The VFA total of FM (129.7 mmol/l) and SBM (153.1 mmol/l) were higher than that of NG (86.4 mmol/l). At 3 and 6 hours after feeding, ammonia in the rumen of SBM was higher than that of NG and FM, indicating higher degraded protein. The BUN at 3 hours after feeding of SBM was higher than that of NG. It can be concluded that protein in SBM was degraded higher than others and the lower pH in rumen of TMR goats was caused by higher VFA produced by TMR goats compared to NG goats.

Prevention of volatile fatty acids production and limitation of odours from winery wastewaters by denitrification.

PubMed

Bories, André; Guillot, Jean-Michel; Sire, Yannick; Couderc, Marie; Lemaire, Sophie-Andréa; Kreim, Virginie; Roux, Jean-Claude

2007-07-01

The effect of the addition of nitrate to winery wastewaters to control the formation of VFA in order to prevent odours during storage and treatment was studied in batch bioreactors at different NO(3)/chemical oxygen demand (COD) ratios and at full scale in natural evaporation ponds (2 x 7000 m(2)) by measuring olfactory intensity. In the absence of nitrate, butyric acid (2304 mgL(-1)), acetic acid (1633 mgL(-1)), propionic acid (1558 mgL(-1)), caproic acid (499 mgL(-1)) and valeric acid (298 mgL(-1)) were produced from reconstituted winery wastewater. For a ratio of NO(3)/COD=0.4 gg(-1), caproic and valeric acids were not formed. The production of butyric and propionic acids was reduced by 93.3% and 72.5%, respectively, at a ratio of NO(3)/COD=0.8, and by 97.4% and 100% at a ratio of NO(3)/COD=1.2 gg(-1). Nitrate delayed and decreased butyric acid formation in relation to the oxidoreduction potential. Studies in ponds showed that the addition of concentrated calcium nitrate (NITCAL) to winery wastewaters (3526 m(3)) in a ratio of NO(3)/COD=0.8 inhibited VFA production, with COD elimination (94%) and total nitrate degradation, and no final nitrite accumulation. On the contrary, in ponds not treated with nitrate, malodorous VFA (from propionic to heptanoïc acids) represented up to 60% of the COD. Olfactory intensity measurements in relation to the butanol scale of VFA solutions and the ponds revealed the pervasive role of VFA in the odour of the untreated pond as well as the clear decrease in the intensity and not unpleasant odour of the winery wastewater pond enriched in nitrates. The results obtained at full scale underscored the feasibility and safety of the calcium nitrate treatment as opposed to concentrated nitric acid.

Monensin and ammoniation or urea supplementation of bermudagrass hay diets for steers.

PubMed

Vagnoni, D B; Craig, W M; Gates, R N; Wyatt, W E; Southern, L L

1995-06-01

One growth trial using crossbred beef steers (297 +/- 2 kg, Exp. 1) and one metabolism trial using Holstein steers (405 +/- 14 kg, Exp. 2) were conducted to evaluate effects of ammoniation (3% of hay DM, added as anhydrous NH3) vs urea supplementation with or without monensin supplementation of mature 'Alicia' bermudagrass hay-based diets for steers. Ammoniation (P < .05), but not urea (P = .26) or monensin (P = .70) supplementation, increased ADG in Exp. 1. In Exp. 2 ammoniation increased hay DMI (P < .05), but urea (P = .88) or monensin (P = .16) had no effect. Supplementation with either monensin (P < .05) or urea (P < .05) decreased ruminal total VFA concentrations. Monensin also decreased the ruminal acetate:propionate ratio (P < .001) and increased ruminal pH (P < .05). Addition of urea to the concentrate supplement decreased the rate of concentrate intake. Both the rate (P < .05) and the potential extent (P < .001) of ruminal forage in situ DM and NDF disappearance were increased by ammonia treatment. Dietary interactions (P < .10) were detected between monensin and ammoniation for rate and potential extent of in situ NDF disappearance and between monensin and urea supplementation (P < .05) for ruminal total free amino acid concentrations. Decreased concentrations of VFA and lower forage digestibilities observed with monensin supplementation in Exp. 2 may explain the failure of monensin to affect ADG in Exp. 1.

The effect of cation source and dietary cation-anion difference on rumen ion concentrations in lactating dairy cows.

PubMed

Catterton, T L; Erdman, R A

2016-08-01

Many studies have focused on the influence of dietary cation-anion difference (DCAD) on animal performance but few have examined the effect of DCAD on the rumen ionic environment. The objective of this study was to examine the effects of DCAD, cation source (Na vs. K), and anion source (Cl vs. bicarbonate or carbonate) on rumen environment and fermentation. The study used 5 rumen-fistulated dairy cows and 5 dietary treatments that were applied using a 5×5 Latin square design with 2-wk experimental periods. Treatments consisted of (1) the basal total mixed ration (TMR); (2) the basal TMR plus 340mEq/kg of Na (dry matter basis) using NaCl; (3) the basal TMR plus 340mEq/kg of K using KCl; (4) the basal TMR plus 340mEq/kg of Na using NaHCO3; and (5) the basal TMR plus 340mEq/kg of K using K2CO3. On the last day of each experimental period, rumen samples were collected and pooled from 5 different locations at 0, 1.5, 3, 4.5, 6, 9, and 12h postfeeding for measurement of rumen pH and concentrations of strong ions and volatile fatty acids (VFA). Dietary supplementation of individual strong ions increased the corresponding rumen ion concentration. Rumen Na was decreased by 24mEq/L when K was substituted for Na in the diet, but added dietary Na had no effect on rumen K. Rumen Cl was increased by 10mEq/L in diets supplemented with Cl. Cation source had no effect on rumen pH or total VFA concentration. Increased DCAD increased rumen pH by 0.10 pH units and increased rumen acetate by 4mEq/L but did not increase total VFA. This study demonstrated that rumen ion concentrations can be manipulated by dietary ion concentrations. If production and feed efficiency responses to DCAD and ionophores in the diet are affected by rumen Na and K concentrations, then manipulating dietary Na and K could be used either to enhance or diminish those responses. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Instability diagnosis and syntrophic acetate oxidation during thermophilic digestion of vegetable waste.

PubMed

Li, Dong; Ran, Yi; Chen, Lin; Cao, Qin; Li, Zhidong; Liu, Xiaofeng

2018-08-01

Effective process monitoring and instability diagnosis are important for stable anaerobic digestion (AD) of vegetable waste (VW). In order to evaluate the performance of thermophilic digestion of VW, to make early diagnosis for instability after organic overload, and to reveal the dynamics of microbial community under different running states, thermophilic AD of VW was carried out under improved organic loading rates (OLR) of 0.5-2.5 g volatile solid (VS)/(L ∙ d) in this study. Gaseous parameters including volumetric methane production rate (VMPR), CH 4 , CO 2 , and H 2 concentrations, and liquid parameters including pH, oxidation-reduction potential, volatile fatty acid (VFA), and total alkalinity (TA), bicarbonate alkalinity (BA), intermediate alkalinity (IA), and ammonia, were monitored. The coupling parameters, such as the CH 4 /CO 2 , VFA/BA, and BA/TA ratios were also used to evaluate stability. The dynamics of syntrophic acetate-oxidizing bacteria (SAOB), acetoclastic methanogens (AM), and hydrogenotrophic methanogens (HM) were analyzed by high-throughput sequencing. The main methanogenic bacteria were HM (Methanothermobacter) during the start-up period of OLR 0.5 gVS/(L ∙ d), while they were AM (Methanosarcina) during the stable period of OLR of 1.0 gVS/(L ∙ d). The VMPR of stable period was about 0.29 L/(L · d) with total VFA concentration below 100 mg/L, CH 4 /CO 2  > 1.3, and BA/TA>0.9. The first instability due to the accumulation of VFA and self-recovery due to syntrophic acetate oxidation occurred at an OLR of 1.5 gVS/(L ∙ d). The syntrophic acetate-oxidizing bacteria probably belong to genus S1 (family Thermotogaceae). The digestion failed at an OLR of 2.0 g VS/(L · d). H 2 was only detected during collapsed period instead of instable period. The total ammonia nitrogen loss and bicarbonate alkalinity (BA) reduction were the primary causes for the instability of AD of VW without effluent recirculation. Compared with single parameters, the CH 4 /CO 2 and BA/total alkalinity (TA) ratios are recommended as early warning indicators for engineering applications of thermophilic AD of VW. Copyright © 2018 Elsevier Ltd. All rights reserved.

Quantitative Gd-DOTA uptake from cerebrospinal fluid into rat brain using 3D VFA-SPGR at 9.4T.

PubMed

Lee, Hedok; Mortensen, Kristian; Sanggaard, Simon; Koch, Palle; Brunner, Hans; Quistorff, Bjørn; Nedergaard, Maiken; Benveniste, Helene

2018-03-01

We propose a quantitative technique to assess solute uptake into the brain parenchyma based on dynamic contrast-enhanced MRI (DCE-MRI). With this approach, a small molecular weight paramagnetic contrast agent (Gd-DOTA) is infused in the cerebral spinal fluid (CSF) and whole brain gadolinium concentration maps are derived. We implemented a 3D variable flip angle spoiled gradient echo (VFA-SPGR) longitudinal relaxation time (T1) technique, the accuracy of which was cross-validated by way of inversion recovery rapid acquisition with relaxation enhancement (IR-RARE) using phantoms. Normal Wistar rats underwent Gd-DOTA infusion into CSF via the cisterna magna and continuous MRI for approximately 130 min using T1-weighted imaging. Dynamic Gd-DOTA concentration maps were calculated and parenchymal uptake was estimated. In the phantom study, T1 discrepancies between the VFA-SPGR and IR-RARE sequences were approximately 6% with a transmit coil inhomogeneity correction. In the in vivo study, contrast transport profiles indicated maximal parenchymal retention of approximately 19% relative to the total amount delivered into the cisterna magna. Imaging strategies for accurate 3D contrast concentration mapping at 9.4T were developed and whole brain dynamic concentration maps were derived to study solute transport via the glymphatic system. The newly developed approach will enable future quantitative studies of the glymphatic system in health and disease states. Magn Reson Med 79:1568-1578, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Effect of fiber source on cecal fermentation and nitrogen recycled through cecotrophy in rabbits.

PubMed

García, J; Carabaño, R; Pérez-Alba, L; de Blas, J C

2000-03-01

The influence of fiber source on fiber digestion in rabbits was investigated. Six fibrous feedstuffs with wide differences in chemical composition and particle size were selected: paprika meal, olive leaves, alfalfa hay, soybean hulls, sodium hydroxide-treated barley straw, and sunflower hulls. Six diets were formulated to contain one of these ingredients as the sole source of fiber. To avoid nutrient imbalances, fiber sources were supplemented with different proportions of a fiber-free concentrate, based on soy protein isolate, wheat flour, lard, and a vitamin and mineral mix, to obtain diets containing at least 3% nitrogen and 5% starch. Daily soft feces excretion, and its NDF, and total and microbial nitrogen content were determined in 60 fattening rabbits (10 per diet). Seven days after the last cecotrophy control, the same animals were used to determine weight of stomach, cecum and their contents, and cecal fermentation traits (pH, VFA and ammonia concentrations, and buffer properties of cecal contents). Stepwise regression analysis showed a positive effect (P < .001) on soft feces excretion, total and microbial nitrogen concentrations in soft feces, cecal acidity, and total VFA in the cecum of dietary pectic constituents (2.9, 3.5, 2.5, .9, and 6.6%) and proportion of fine particles (< .315 mm) (1.8, .9, 1.3, .15, and .9%) per each increment of one percentage unit of the independent variables. Proportion of fine particles also increased weight of cecal contents (P < .001). Soft feces excretion and weight of stomach and of its contents increased (P < .001) by 5.2, 2.8, and 10.2% per each percentage unit increment of proportion of large particles (> 1.25 mm). Degree of lignification of NDF decreased total nitrogen concentration in soft feces and cecal VFA concentration (P < .001). Source of fiber affected cecal pH not only by its influence on the cecal concentrations of the final products of fermentation, but also through its effect on the pH of dry cecal contents (P < .001). The latter was negatively correlated with dietary proportion of fine particles, degree of lignification of NDF, and base-buffering capacity of dry cecal contents (r = -.52, -.37, and -.49, respectively). From these results, we conclude that pectic constituent concentration, degree of lignification of NDF, and particle size are the variables that best characterize the influence of the source of fiber on soft feces excretion and cecal fermentation traits in rabbits.

Comparison of microbial fermentation of high- and low-forage diets in Rusitec, single-flow continuous-culture fermenters and sheep rumen.

PubMed

Carro, M D; Ranilla, M J; Martín-García, A I; Molina-Alcaide, E

2009-04-01

Eight Rusitec and eight single-flow continuous-culture fermenters (SFCCF) were used to compare the ruminal fermentation of two diets composed of alfalfa hay and concentrate in proportions of 80 : 20 (F80) and 20 : 80 (F20). Results were validated with those obtained previously in sheep fed the same diets. Rusitec fermenters were fed once daily and SFCCF twice, but liquid dilution rates were similar in both types of fermenters. Mean values of pH over the 12 h postfeeding were higher (P < 0.001) in Rusitec than in SFCCF, with diet F80 showing higher values (P < 0.001) in both types of fermenters. Concentrations of total volatile fatty acids (VFA) were higher (P < 0.001) in SFCCF than in Rusitec, and in both systems were higher (P = 0.002) for diet F20 than for diet F80. There were significant differences between systems in the proportions of the main VFA, and a fermentation system × diet interaction (P < 0.001) was detected for all VFA with the exception of valerate. No differences (P = 0.145) between the two types of fermenters were detected in dry matter (DM) digestibility, but NDF, microbial N flow and its efficiency were higher (P = 0.001) in SFCCF compared to Rusitec. Whereas pH values and VFA concentrations remained fairly stable through the day in both in vitro systems, pH dropped and VFA increased shortly after feeding in sheep rumen reaching the minimum and maximal values, respectively, about 4 h after feeding. Both in vitro systems detected differences between diets similar to those found in sheep for liquid dilution rate, pH values, DM digestibility, microbial N flow and growth efficiency. In contrast, acetate/propionate ratios were lower for diet F20 than for F80 in sheep rumen (2.73 and 3.97) and SFCCF (3.07 and 4.80), but were higher for diet F20 compared to F80 (4.29 and 3.40) in Rusitec, with values considered to be unphysiological for high-concentrate diets. In vivo NDF digestibility was affected (P = 0.017) by diet, but no differences between diets (P > 0.05) were found in any in vitro system. A more precise control of pH in both types of fermenters and a reduction of concentrate retention time in Rusitec could probably improve the simulation of in vivo fermentation.

Effects of synchronicity of carbohydrate and protein degradation on rumen fermentation characteristics and microbial protein synthesis.

PubMed

Seo, J K; Kim, M H; Yang, J Y; Kim, H J; Lee, C H; Kim, K H; Ha, Jong K

2013-03-01

A series of in vitro studies were carried out to determine i) the effects of enzyme and formaldehyde treatment on the degradation characteristics of carbohydrate and protein sources and on the synchronicity of these processes, and ii) the effects of synchronizing carbohydrate and protein supply on rumen fermentation and microbial protein synthesis (MPS) in in vitro experiments. Untreated corn (C) and enzyme-treated corn (EC) were combined with soy bean meal with (ES) and without (S) enzyme treatment or formaldehyde treatment (FS). Six experimental feeds (CS, CES, CFS, ECS, ECES and ECFS) with different synchrony indices were prepared. Highly synchronous diets had the greatest dry matter (DM) digestibility when untreated corn was used. However, the degree of synchronicity did not influence DM digestibility when EC was mixed with various soybean meals. At time points of 12 h and 24 h of incubation, EC-containing diets showed lower ammonia-N concentrations than those of C-containing diets, irrespective of the degree of synchronicity, indicating that more efficient utilization of ammonia-N for MPS was achieved by ruminal microorganisms when EC was offered as a carbohydrate source. Within C-containing treatments, the purine base concentration increased as the diets were more synchronized. This effect was not observed when EC was offered. There were significant effects on VFA concentration of both C and S treatments and their interactions. Similar to purine concentrations, total VFA production and individual VFA concentration in the groups containing EC as an energy source was higher than those of other groups (CS, CES and CFS). The results of the present study suggested that the availability of energy or the protein source are the most limiting factors for rumen fermentation and MPS, rather than the degree of synchronicity.

In vitro digestion and fermentation characteristics of canola co-products simulate their digestion in the pig intestine.

PubMed

Woyengo, T A; Jha, R; Beltranena, E; Zijlstra, R T

2016-06-01

Canola co-products are sources of amino acid and energy in pig feeds, but their fermentation characteristics in the pig intestine are unknown. Thus, we determined the in vitro fermentation characteristics of the canola co-products Brassica juncea solvent-extracted canola meal (JSECM), Brassica napus solvent-extracted canola meal (NSECM), B. napus expeller-pressed canola meal (NEPCM) and B. napus cold-pressed canola cake (NCPCC) in comparison with soybean meal (SBM). Samples were hydrolysed in two steps using pepsin and pancreatin. Subsequently, residues were incubated in a buffer solution with fresh pig faeces as inocula for 72 h to measure gas production. Concentration of volatile fatty acids (VFA) per gram of dry matter (DM) of feedstuff was measured in fermented solutions. Apparent ileal digestibility (AID) and apparent hindgut fermentation (AHF) of gross energy (GE) for feedstuffs were obtained from pigs fed the same feedstuffs. On DM basis, SBM, JSECM, NSECM, NEPCM and NCPCC contained 15, 19, 22, 117 and 231 g/kg ether extract; and 85, 223, 306, 208 and 176 g/kg NDF, respectively. In vitro digestibility of DM (IVDDM) of SBM (82.3%) was greater (P<0.05) than that of JSECM (68.5%), NSECM (63.4%), NEPCM (67.5%) or NCPCC (69.8%). The JSECM had greater (P<0.05) IVDDM than NSECM. The IVDDM for NSECM was lower (P<0.05) than that for NEPCM, which was lower (P<0.05) than that for NCPCC. Similarly, AID of GE was greatest for SBM followed by NCPCC, JSECM, NEPCM and then NSECM. Total VFA production for SBM (0.73 mmol/g) was lower (P<0.05) than that of JSECM (1.38 mmol/g) or NSECM (1.05 mmol/g), but not different from that of NEPCM (0.80 mmol/g) and NCPCC (0.62 mmol/g). Total VFA production of JSECM was greater (P<0.05) than that of NSECM. Total VFA production of NSECM was greater (P<0.05) than that of NEPCM or NCPCC, which differed (P<0.05). The ranking of feedstuffs for total VFA production was similar to AHF of GE. In conclusion, in vitro fermentation characteristics of canola co-products and SBM simulated their fermentation in the small and large intestine of pigs, respectively. The 30% greater VFA production for JSECM than NSECM due to lower lignified fibre of JSECM indicates that fermentation characteristics differ between canola species. The NSECM had the highest fermentability followed by NEPCM and then NCPCC, indicating that fat in canola co-products can limit their fermentability in the hindgut.

Effects of gas composition in headspace and bicarbonate concentrations in media on gas and methane production, degradability, and rumen fermentation using in vitro gas production techniques.

PubMed

Patra, Amlan Kumar; Yu, Zhongtang

2013-07-01

Headspace gas composition and bicarbonate concentrations in media can affect methane production and other characteristics of rumen fermentation in in vitro gas production systems, but these 2 important factors have not been evaluated systematically. In this study, these 2 factors were investigated with respect to gas and methane production, in vitro digestibility of feed substrate, and volatile fatty acid (VFA) profile using in vitro gas production techniques. Three headspace gas compositions (N2+ CO2+ H2 in the ratio of 90:5:5, CO2, and N2) with 2 substrate types (alfalfa hay only, and alfalfa hay and a concentrate mixture in a 50:50 ratio) in a 3×2 factorial design (experiment 1) and 3 headspace compositions (N2, N2 + CO2 in a 50:50 ratio, and CO2) with 3 bicarbonate concentrations (80, 100, and 120 mM) in a 3×3 factorial design (experiment 2) were evaluated. In experiment 1, total gas production (TGP) and net gas production (NGP) was the lowest for CO2, followed by N2, and then the gas mixture. Methane concentration in headspace gas after fermentation was greater for CO2 than for N2 and the gas mixture, whereas total methane production (TMP) and net methane production (NMP) were the greatest for CO2, followed by the gas mixture, and then N2. Headspace composition did not affect in vitro digestibility or the VFA profile, except molar percentages of propionate, which were greater for CO2 and N2 than for the gas mixture. Methane concentration in headspace gas, TGP, and NGP were affected by the interaction of headspace gas composition and substrate type. In experiment 2, increasing concentrations of CO2 in the headspace decreased TGP and NGP quadratically, but increased the concentrations of methane, NMP, and in vitro fiber digestibility linearly, and TMP quadratically. Fiber digestibility, TGP, and NGP increased linearly with increasing bicarbonate concentrations in the medium. Concentrations of methane and NMP were unaffected by bicarbonate concentration, but TMP tended to increase due to increasing bicarbonate concentration. Although total VFA concentration and molar percentage of butyrate were unchanged, the molar percentage of acetate, and acetate-to-propionate ratio decreased, whereas the molar percentage of propionate increased quadratically with increasing bicarbonate concentration. This study demonstrated for the first time that headspace composition, especially CO2 content, and bicarbonate concentration in media could significantly influence gas and methane production, and rumen fermentation in gas production techniques. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Ultrasonic enhancement of waste activated sludge hydrolysis and volatile fatty acids accumulation at pH 10.0.

PubMed

Yan, Yuanyuan; Feng, Leiyu; Zhang, Chaojie; Wisniewski, Christelle; Zhou, Qi

2010-06-01

Volatile fatty acids (VFA), the preferred carbon source for biological nutrients removal, can be produced by waste activated sludge (WAS) anaerobic fermentation. However, because the rate of VFA accumulation is limited by that of WAS hydrolysis and VFA is always consumed by methanogens at acidic or neutral pHs, the ultrasonic pretreatment which can accelerate the rate of WAS hydrolysis, and alkaline adjustment which can inhibit the activities of methanogens, were, therefore, used to improve WAS hydrolysis and VFA accumulation in this study. Experiment results showed that the combination of ultrasonic pretreatment and alkaline adjustment caused significant enhancements of WAS hydrolysis and VFA accumulation. The study of ultrasonic energy density effect revealed that energy density influenced not only the total VFA accumulation but also the percentage of individual VFA. The maximal VFA accumulation (3109.8mg COD/L) occurred at ultrasonic energy density of 1.0kW/L and fermentation time of 72h, which was more than two times that without ultrasonic treatment (1275.0mg COD/L). The analysis of VFA composition showed that the percentage of acetic acid ranked the first (more than 40%) and those of iso-valeric and propionic acids located at the second and third places, respectively. Thus, the suitable ultrasonic conditions combined with alkaline adjustment for VFA accumulation from WAS were ultrasonic energy density of 1.0kW/L and fermentation time of 72h. Also, the key enzymes related to VFA formation exhibited the highest activities at ultrasonic energy density of 1.0kW/L, which resulted in the greatest VFA production during WAS fermentation at pH 10.0. Copyright 2010 Elsevier Ltd. All rights reserved.

Effects of lipid concentration on anaerobic co-digestion of municipal biomass wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Yifei, E-mail: sunif@buaa.edu.cn; Wang, Dian; Yan, Jiao

2014-06-01

Highlights: • Lipid in municipal biomass would not inhibited the anaerobic digestion process. • A lipid concentration of 65% of total VS was the inhibition concentration. • The amount of Brevibacterium decreased with the increasing of the lipid contents. • Long chain fatty acids stacked on the methanogenic bacteria and blocked the mass transfer process. - Abstract: The influence of the lipid concentration on the anaerobic co-digestion of municipal biomass waste and waste-activated sludge was assessed by biochemical methane potential (BMP) tests and by bench-scale tests in a mesophilic semi-continuous stirred tank reactor. The effect of increasing the volatile solidmore » (VS) concentration of lipid from 0% to 75% was investigated. BMP tests showed that lipids in municipal biomass waste could enhance the methane production. The results of bench-scale tests showed that a lipids concentration of 65% of total VS was the inhibition concentration. Methane yields increased with increasing lipid concentration when lipid concentrations were below 60%, but when lipid concentration was set as 65% or higher, methane yields decreased sharply. When lipid concentrations were below 60%, the pH values were in the optimum range for the growth of methanogenic bacteria and the ratios of volatile fatty acid (VFA)/alkalinity were in the range of 0.2–0.6. When lipid concentrations exceeded 65%, the pH values were below 5.2, the reactor was acidized and the values of VFA/alkalinity rose to 2.0. The amount of Brevibacterium decreased with increasing lipid content. Long chain fatty acids stacked on the methanogenic bacteria and blocked the mass transfer process, thereby inhibiting anaerobic digestion.« less

Anaerobic monodigestion of poultry manure: determination of operational parameters for CSTR.

PubMed

Chamy, R; León, C; Vivanco, E; Poirrier, P; Ramos, C

2012-01-01

In this work the anaerobic monodigestion for the treatment of turkey manure was evaluated, without its codigestion with another substrate. The effect of the organic loading rate (OLR) and the substrate concentration (high total solids (TS) concentration) or product concentration (high volatile fatty acids (VFA) and/or ammonia (NH(3)-N) concentrations) was studied. The results show that for a continuous stirred tank reactor (CSTR) operation, a maximum of 40 g/L of TS and 4.0 g/L of ammonium (NH(4)(+)) was required. In addition, the maximum organic loading rate (OLR) will not exceed 1.5 kg VS/m(3)d. Higher TS and NH(4)(+) concentrations and OLR lead to a reduction on the methane productivity and volatile solids (VS) removal. During the CSTR operation, a high alkalinity concentration (above 10 g/L CaCO(3)) was found; this situation allowed maintaining a constant and appropriate pH (close to 7.8), despite the VFA accumulation. In this sense, the alkalinity ratio (α) is a more appropriate control and monitoring parameter of the reactor operation compared to pH. Additionally, with this parameter a VS removal of 80% with a methane productivity of 0.50 m(3)(CH4)/m(3)(R)d is achieved.

Effects of supplemental energy and protein on forage digestion and urea kinetics in growing beef cattle.

PubMed

Bailey, E A; Titgemeyer, E C; Olson, K C; Brake, D W; Jones, M L; Anderson, D E

2012-10-01

Effects of supplemental energy sources on nutrient digestion and urea kinetics at 2 levels of degradable intake protein were evaluated in cattle (Bos taurus). Six ruminally and duodenally cannulated steers (208 ± 17 kg) were used in a 6 × 6 Latin square with treatments arranged as a 3 × 2 factorial. Energy treatments included a control, 600 g glucose dosed ruminally once daily, and 480 g VFA infused ruminally over 8 h daily. Casein (120 or 240 g) was dosed ruminally once daily. Steers had ad libitum access to prairie hay (5.8% CP). Jugular infusion of (15)N(15)N-urea with measurement of enrichment in urine was used to measure urea kinetics. Infusing VFA decreased (P < 0.01) forage intake by 27%. Supplementing glucose decreased (P < 0.01) total tract NDF digestibility and tended to decrease ruminal NDF digestibility; depressions in response to glucose tended to be greater at the lower level of casein. Increasing casein decreased (P < 0.02) ruminal pH. Infusing VFA decreased pH only during infusions, whereas glucose decreased pH 2 h after dosing. Ruminal concentrations of NH(3), acetate, and propionate decreased and butyrate concentration increased when glucose was supplemented. Increasing casein supplementation increased (P < 0.01) ruminal concentrations of NH(3), acetate, and propionate. Supplemental energy decreased (P = 0.03) plasma urea-N concentration, but casein level did not affect it (P = 0.16). Microbial N flow was greater (P < 0.04) for 240 than for 120 g/d casein but was not affected by supplemental energy (P = 0.23). Urea-N entry rate and gut entry of urea-N were not affected (P ≥ 0.12) by supplemental energy or casein, but the proportion of urea production that was recycled to the gut was less (P = 0.01) when 240 g/d rather than 120 g/d casein was provided. Compared with VFA, glucose tended (P = 0.07) to increase the proportion of urea-N entry rate that was recycled to the gut. Supplementation with glucose led to more (P = 0.01) microbial uptake of recycled urea than did supplementation with VFA. Urea recycling did not differ greatly among treatments despite impacts on ruminal pH and NH(3) and on plasma urea-N that were expected to alter urea transport across ruminal epithelium. Lack of treatment effects on urea production indicate that the complete diets did not provide excessive amounts of N and that increases of intestinally available AA were used efficiently by cattle for protein deposition.

Effects of Marine and Freshwater Macroalgae on In Vitro Total Gas and Methane Production

PubMed Central

Machado, Lorenna; Magnusson, Marie; Paul, Nicholas A.; de Nys, Rocky; Tomkins, Nigel

2014-01-01

This study aimed to evaluate the effects of twenty species of tropical macroalgae on in vitro fermentation parameters, total gas production (TGP) and methane (CH4) production when incubated in rumen fluid from cattle fed a low quality roughage diet. Primary biochemical parameters of macroalgae were characterized and included proximate, elemental, and fatty acid (FAME) analysis. Macroalgae and the control, decorticated cottonseed meal (DCS), were incubated in vitro for 72 h, where gas production was continuously monitored. Post-fermentation parameters, including CH4 production, pH, ammonia, apparent organic matter degradability (OMd), and volatile fatty acid (VFA) concentrations were measured. All species of macroalgae had lower TGP and CH4 production than DCS. Dictyota and Asparagopsis had the strongest effects, inhibiting TGP by 53.2% and 61.8%, and CH4 production by 92.2% and 98.9% after 72 h, respectively. Both species also resulted in the lowest total VFA concentration, and the highest molar concentration of propionate among all species analysed, indicating that anaerobic fermentation was affected. Overall, there were no strong relationships between TGP or CH4 production and the >70 biochemical parameters analysed. However, zinc concentrations >0.10 g.kg−1 may potentially interact with other biochemical components to influence TGP and CH4 production. The lack of relationship between the primary biochemistry of species and gas parameters suggests that significant decreases in TGP and CH4 production are associated with secondary metabolites produced by effective macroalgae. The most effective species, Asparagopsis, offers the most promising alternative for mitigation of enteric CH4 emissions. PMID:24465524

Effects of distillers dried grains with solubles on amino acid, energy, and fiber digestibility and on hindgut fermentation of dietary fiber in a corn-soybean meal diet fed to growing pigs.

PubMed

Urriola, P E; Stein, H H

2010-04-01

The objective of this experiment was to measure the effect of distillers dried grains with solubles (DDGS) on the digestibility of AA, energy, and fiber, on the fermentation of fiber, and on the first appearance of digesta at the end of the ileum, in the cecum, and in the feces of growing pigs fed a corn-soybean meal-based diet. Sixteen pigs (initial BW = 38.0 +/- 1.6 kg) were prepared with a T-cannula in the distal ileum and a T-cannula in the cecum and allotted to 2 treatments. In period 1, all pigs were fed a corn-soybean meal diet. In periods 2, 3, and 4, pigs were fed the control diet or a diet containing corn, soybean meal, and 30% DDGS. First appearance of digesta at the end of the ileum, in the cecum, and over the entire intestinal tract was measured at the end of period 4. The apparent ileal digestibility (AID) and the apparent total tract digestibility (ATTD) of nutrients were measured, and the concentration of VFA was analyzed in ileal, cecal, and fecal samples. The AID of Lys (74.1%) in the DDGS diet was less (P < 0.05) than in the control diet (78.6%), but the AID of most other AA and GE, NDF, and total dietary fiber (TDF) were not different between the 2 diets. The ATTD of GE (81.0%), NDF (57.2%), TDF (55.5%), and DM (81.7%) were less (P < 0.05) in the DDGS diet than in the control diet (86.0, 69.3, 66.0, and 87.2%, respectively). The concentration of VFA in ileal, cecal, and fecal samples was not different between pigs fed the 2 diets. The pH of ileal and cecal digesta from pigs fed the DDGS diet (6.3 and 5.5) was greater (P < 0.01) than from pigs fed the control diet (5.8 and 5.3). The ATTD of DM, GE, ADF, NDF, and TDF did not change with collection period, but the AID of ADF, NDF, and TDF increased (P < 0.05) from period 2 to period 4. The concentration of all VFA, except isobutyrate, was greater (P < 0.05) in cecal samples from period 4 compared with period 2, and the concentration of all VFA except propionate and isovalerate were greater (P < 0.05) in fecal samples collected in period 4 compared with those collected in period 2. The first appearance of digesta at the end of the ileum, in the cecum, and in the feces was not affected by DDGS. In conclusion, pigs fed the diet containing DDGS had less digestibility of Lys, GE, ADF, NDF, and TDF than pigs fed the control diet. The digestibility of DM and GE was not influenced by collection period, but the concentration of VFA in cecal digesta and feces increased with the length of time pigs received the diets.

Rates of production of acetate, propionate, and butyrate in the rumen of lactating dairy cows given normal and low-roughage diets.

PubMed

Sutton, J D; Dhanoa, M S; Morant, S V; France, J; Napper, D J; Schuller, E

2003-11-01

Five lactating dairy cows with a permanent cannula in the rumen were given (kg DM/d) a normal diet (7.8 concentrates, 5.1 hay) or a low-roughage (LR) diet (11.5 concentrates, 1.2 hay) in two meals daily in a two-period crossover design. Milk fat (g/kg) was severely reduced on diet LR. To measure rates of production of individual volatile fatty acids (VFA) in the rumen, 0.5 mCi 1-(14)C-acetic acid, 2-(14)C-propionic acid, or 1-(14)C-n-butyric acid were infused into the rumen for 22 h at intervals of 2 to 6 d; rumen samples were taken over the last 12 h. To measure rumen volume, we infused Cr-EDTA into the rumen continuously, and polyethylene glycol was injected 2 h before the morning feed. Results were very variable, so volumes measured by rumen emptying were used instead. Net production of propionic acid more than doubled on LR, but acetate and butyrate production was only numerically lower. Net production rates pooled across both diets were significantly related to concentrations for each VFA. Molar proportions of net production were only slightly higher than molar proportions of concentrations for acetate and propionate but were lower for butyrate. The net energy value (MJ/d) of production of the three VFA increased from 89.5 on normal to 109.1 on LR, equivalent to 55 and 64% of digestible energy, respectively. Fully interchanging, three-pool models of VFA C fluxes are presented. It is concluded that net production rates of VFA can be measured in non-steady states without the need to measure rumen volumes.

Can direct gas-liquid chromatography of clinical samples detect specific organisms?

PubMed Central

Watt, B; Geddes, P A; Greenan, O A; Napier, S K; Mitchell, A

1982-01-01

A total of 1929 samples was analyzed by direct gas-liquid chromatography and the volatile fatty acid (VFA) patterns of the positive samples were compared with the results of culture. There was no correlation between any bacterial genus or species and the detailed VFA patterns although the presence of butyric or valeric acids, or both, was generally associated with the presence of anaerobes and that of acetic acid was generally associated with aerobic bacteria; however, the technique could not predict the nature of the subsequent bacterial isolate. There was also poor correlation between the VFA pattern in a given sample and the VFA pattern(s) of anaerobic bacteria subsequently isolated from that sample. PMID:7096589

Study of Local Herb Potency as Rumen Modifier: The Effect of Red Ginger (Zingiber officinale Var.Rubrum) on Parameters of Ruminal Fermentation In Vitro

NASA Astrophysics Data System (ADS)

Kurniawati, A.; Widodo; Artama, W. T.; Yusiati, L. M.

2018-02-01

Essential oil is one of rumen modifier alternatives due to its antimicrobial property. Red ginger is one of local herbs with high essential oil content. The effect of red ginger on rumen fermentation parameters was studied in this research using in vitro gas production method. Five level of red ginger meal was added to the diet to meet final essential oil concentration in fermentation medium of 0, 25, 50, 75 and 100 mg/L. Substrate of fermentation as microbial feed composed of Penisetum hybride, rice bran, and wheat pollard in ratio 60:20:20 DM basis. Fermentation was carried out for 24 h at 39°C. Total gas production was measured at the end of incubation and sample for methane analysis was taken. Medium sample was taken for analysis of pH, ammonium and VFA concentration, microbial protein and protozoa number. Data showed that addition of red ginger in the diet did not affect the pH, ammonia and VFA concentration, microbial protein and also protozoa number. However, red ginger addition significantly decrease ammonia concentration in all treatment. It could be concluded that addition of red ginger in the diet reduced degradation protein in the rumen as illustrated in lower ammonia concentration.

Early warning indicators for process failure due to organic overloading by rapeseed oil in one-stage continuously stirred tank reactor, sewage sludge and waste digesters.

PubMed

Kleyböcker, A; Liebrich, M; Verstraete, W; Kraume, M; Würdemann, H

2012-11-01

Early warning indicators for process failures were investigated to develop a reliable method to increase the production efficiency of biogas plants. Organic overloads by the excessive addition of rapeseed oil were used to provoke the decrease in the gas production rate. Besides typical monitoring parameters, as pH, methane and hydrogen contents, biogas production rate and concentrations of fatty acids; carbon dioxide content, concentrations of calcium and phosphate were monitored. The concentration ratio of volatile fatty acids to calcium acted as an early warning indicator (EWI-VFA/Ca). The EWI-VFA/Ca always clearly and reliably indicated a process imbalance by exhibiting a 2- to 3-fold increase 3-7days before the process failure occurred. At this time, it was still possible to take countermeasures successfully. Furthermore, increases in phosphate concentration and in the concentration ratio of phosphate to calcium also indicated a process failure, in some cases, even earlier than the EWI-VFA/Ca. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of sulfur and monensin concentrations on in vitro dry matter disappearance, hydrogen sulfide production, and volatile fatty acid concentrations in batch culture ruminal fermentations.

PubMed

Smith, D R; Dilorenzo, N; Leibovich, J; May, M L; Quinn, M J; Homm, J W; Galyean, M L

2010-04-01

Effects of monensin (MON) and S on in vitro fermentation and H(2)S production were evaluated in 2 experiments. In Exp. 1, 2 ruminally cannulated steers were adapted (>14 d) to a 75% concentrate diet [steam-flaked corn (SFC)-based], and ruminal fluid was collected approximately 4 h after feeding. Substrate composed (DM basis) of 85.2% SFC, 9% alfalfa hay, 5% cottonseed meal, and 0.8% urea was added with ruminal fluid and buffer to sealed 125-mL serum bottles to allow for gas collection. A Na(2)SO(4) solution was added to yield S equivalent to 0.2, 0.4, and 0.8% of substrate DM, and MON was included at 0, 2, 4, and 6 mg/L of culture volume. Bottle head-space gas was analyzed for H(2)S. No MON (P = 0.29) or MON x S interaction (P = 0.41) effects were detected for H(2)S production. Increasing S linearly increased (P < 0.01) H(2)S production (micromoles/g of fermented DM). The IVDMD (average 70.0%) was not affected by MON (P = 0.93), S (P = 0.18), or the MON x S interaction (P = 0.56). Total VFA concentrations were not affected by MON (P = 0.87), S (P = 0.14), or the MON x S interaction (P = 0.86), but increasing MON linearly decreased (P 21 d) to a 75% concentrate diet (SFC base) that contained 15% (DM basis) wet corn distillers grains plus solubles (WDGS) and MON at 22 mg/kg of DM. In vitro substrate DM was composed of 75.4% SFC, 15% WDGS, 9% alfalfa hay, and 0.6% urea, and S and MON concentrations were the same as in Exp. 1. No effects of MON (P = 0.93) or the MON x S interaction (P = 0.99) were noted for H(2)S production; however, increasing S linearly increased (P < 0.01) H(2)S production. No effects of MON (P = 0.16), S (P = 0.43), or the MON x S interaction (P = 0.10) were noted for IVDMD (average 70.9%). Total VFA concentrations were not affected by MON (P = 0.40), S (P = 0.26), or the MON x S interaction (P = 0.59). As in Exp. 1, increasing MON linearly decreased (P < 0.05) molar proportions of acetate, butyrate, and A:P and linearly increased (P < 0.01) propionate. Increasing S concentration increased in vitro H(2)S production, but S did not affect VFA concentrations and proportions. Monensin did not affect in vitro H(2)S production, and changes in VFA molar proportions were evident with MON regardless of S concentration.

Optimization of hydrolysis and volatile fatty acids production from sugarcane filter cake: Effects of urea supplementation and sodium hydroxide pretreatment.

PubMed

Janke, Leandro; Leite, Athaydes; Batista, Karla; Weinrich, Sören; Sträuber, Heike; Nikolausz, Marcell; Nelles, Michael; Stinner, Walter

2016-01-01

Different methods for optimization the anaerobic digestion (AD) of sugarcane filter cake (FC) with a special focus on volatile fatty acids (VFA) production were studied. Sodium hydroxide (NaOH) pretreatment at different concentrations was investigated in batch experiments and the cumulative methane yields fitted to a dual-pool two-step model to provide an initial assessment on AD. The effects of nitrogen supplementation in form of urea and NaOH pretreatment for improved VFA production were evaluated in a semi-continuously operated reactor as well. The results indicated that higher NaOH concentrations during pretreatment accelerated the AD process and increased methane production in batch experiments. Nitrogen supplementation resulted in a VFA loss due to methane formation by buffering the pH value at nearly neutral conditions (∼ 6.7). However, the alkaline pretreatment with 6g NaOH/100g FCFM improved both the COD solubilization and the VFA yield by 37%, mainly consisted by n-butyric and acetic acids. Copyright © 2015 Elsevier Ltd. All rights reserved.

Volatile fatty acids production from marine macroalgae by anaerobic fermentation.

PubMed

Pham, Thi Nhan; Nam, Woo Joong; Jeon, Young Joong; Yoon, Hyon Hee

2012-11-01

Volatile fatty acids (VFAs) were produced from the marine macroalgae, Laminaria japonica, Pachymeniopsis elliptica, and Enteromorpha crinite by anaerobic fermentation using a microbial community derived from a municipal wastewater treatment plant. Methanogen inhibitor (iodoform), pH control, substrate concentration, and alkaline and thermal pretreatments affected VFA productivity. Acetic, propionic, and butyric acids were the main products. A maximum VFA concentration of 15.2g/L was obtained from 50 g/L of L. japonica in three days at 35°C and pH 6.5-7.0. Pretreatment with 0.5 N NaOH improved VFA productivity by 56% compared to control. The result shows the applicability of marine macroalgae as biomass feedstock for the production of VFAs which can be converted to mixed alcohol fuels. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of the Organic Loading Rate Increase and the Presence of Zeolite on Microbial Community Composition and Process Stability During Anaerobic Digestion of Chicken Wastes.

PubMed

Ziganshina, Elvira E; Belostotskiy, Dmitry E; Ilinskaya, Olga N; Boulygina, Eugenia A; Grigoryeva, Tatiana V; Ziganshin, Ayrat M

2015-11-01

This study investigates the effect of the organic loading rate (OLR) increase from 1.0 to 3.5 g VS L(-1) day(-1) at constant hydraulic retention time (HRT) of 35 days on anaerobic reactors' performance and microbial diversity during mesophilic anaerobic digestion of ammonium-rich chicken wastes in the absence/presence of zeolite. The effects of anaerobic process parameters on microbial community structure and dynamics were evaluated using a 16S ribosomal RNA gene-based pyrosequencing approach. Maximum 12 % of the total ammonia nitrogen (TAN) was efficiently removed by zeolite in the fixed zeolite reactor (day 87). In addition, volatile fatty acids (VFA) in the fixed zeolite reactor accumulated in lower concentrations at high OLR of 3.2-3.5 g VS L(-1) day(-1). Microbial communities in the fixed zeolite reactor and reactor without zeolite were dominated by various members of Bacteroidales and Methanobacterium sp. at moderate TAN and VFA levels. The increase of the OLR accompanied by TAN and VFA accumulation and increase in pH led to the predominance of representatives of the family Erysipelotrichaceae and genera Clostridium and Methanosarcina. Methanosarcina sp. reached relative abundances of 94 and 57 % in the fixed zeolite reactor and reactor without zeolite at the end of the experimental period, respectively. In addition, the diminution of Synergistaceae and Crenarchaeota and increase in the abundance of Acholeplasmataceae in parallel with the increase of TAN, VFA, and pH values were observed.

Oleaginous yeast Yarrowia lipolytica culture with synthetic and food waste-derived volatile fatty acids for lipid production.

PubMed

Gao, Ruiling; Li, Zifu; Zhou, Xiaoqin; Cheng, Shikun; Zheng, Lei

2017-01-01

The sustainability of microbial lipids production from traditional carbon sources, such as glucose or glycerol, is problematic given the high price of raw materials. Considerable efforts have been directed to minimize the cost and find new alternative carbon sources. Volatile fatty acids (VFAs) are especially attractive raw materials, because they can be produced from a variety of organic wastes fermentation. Therefore, the use of volatile fatty acids as carbon sources seems to be a feasible strategy for cost-effective microbial lipid production. Lipid accumulation in Y. lipolytica using synthetic and food waste-derived VFAs as substrates was systematically compared and evaluated in batch cultures. The highest lipid content obtained with acetic, butyric, and propionic acids reached 31.62 ± 0.91, 28.36 ± 0.74, and 28.91 ± 0.66%, respectively. High concentrations of VFA inhibited cell growth in the following order: butyric acid > propionic acid > acetic acid. Within a 30-day experimental period, Y. lipolytica could adapt up to 20 g/L acetic acid, whereas the corresponding concentration of propionic acid and butyric acid were 10 and 5 g/L, respectively. Cultures on a VFA mixture showed that the utilization of different types of VFA by Y. lipolytica was not synchronized but rather performed in a step-wise manner. Although yeast fermentation is an exothermic process, and the addition of VFA will directly affect the pH of the system by increasing environmental acidity, cultures at a cultivation temperature of 38 °C and uncontrolled pH demonstrated that Y. lipolytica had high tolerance in the high temperature and acidic environment when a low concentration (2.5 g/L) of either synthetic or food waste-derived VFA was used. However, batch cultures fed with food fermentate yielded lower lipid content (18.23 ± 1.12%) and lipid productivity (0.12 ± 0.02 g/L/day). The lipid composition obtained with synthetic and food waste-derived VFA was similar to commercial biodiesel feedstock. This work demonstrated the feasibility of utilizing synthetic and food waste-derived VFA for lipid production by Y. lipolytica . The good adaptability of Y. lipolytica to the high temperature and acidic environment further illustrated its considerable potential for practical application.

Continuous anaerobic digestion of food waste and design of digester with lipid removal.

PubMed

Li, Dong; Sun, Yongming; Guo, Yanfeng; Yuan, Zhenhong; Wang, Yao; Zhen, Feng

2013-01-01

Separation of municipal solid waste has been implemented in many cities in China. As a major component of municipal solid waste, food waste can be treated by anaerobic digestion (AD) for energy production. To provide reference data for disposing of food waste through engineering applications, continuous AD was carried out under various organic loading rates (OLRs) at 27 +/- 2 degrees C in the laboratory. The anaerobic reactor was stable with pH 7.0-7.1, total volatile fatty acid (VFA) concentrations of 206-746 mg/L, and NH4+ -N concentrations of 525-1293 mg/L when the OLR was 1.118-5.588 kg volatile solids (VS)/m(3) x d. The maximum volumetric biogas production rate was 4.41 L/L x d when the OLR was increased to 5.588 kg VS/m(3) x d with a hydraulic retention time of 30 d. When the OLR was increased to 6.706 and 8.382 kg VS/m(3) x d, biogas production was seriously inhibited by VFAs, with maximum total VFA and propionate concentrations of 8738 mg/L and 2864 mg/L, respectively. Due to the incomplete degradation of lipids, the specific methane production rate of 353-488 L/kg VS accounted for 55.2-76.3% of the theoretical methane potential calculated based on the component composition. A retrofitted anaerobic digester with lipid removal was designed to improve the efficiency.

The effects of intermittent use of the SGLT-2 inhibitor, dapagliflozin, in overweight patients with type 2 diabetes in Japan: a randomized, crossover, controlled clinical trial.

PubMed

Kato, Kanako; Suzuki, Kunihiro; Aoki, Chie; Sagara, Masaaki; Niitani, Takafumi; Wakamatsu, Sho; Yanagi, Kazunori; Aso, Yoshimasa

2017-06-01

This study examined the effects of short-term administration of the sodium glucose cotransporter 2 (SGLT-2) inhibitor, dapagliflozin, on visceral fat area (VFA) in Japanese patients with type 2 diabetes. In this randomized, crossover, controlled clinical trial, overweight patients with type 2 diabetes were randomized to treatment with 5 mg dapagliflozin for the first (n = 27) or second 12-week study period (n = 29). The parameters evaluated at baseline and after 12 and 24 weeks included blood pressure, hemoglobin A1c (HbA1c), body composition, VFA, and subcutaneous fat area (SFA). In both groups, dapagliflozin administration improved the levels of HbA1c, body weight, blood pressure, total fat mass, and VFA. Cessation of dapagliflozin, however, reversed the improvements in HbA1c, blood pressure, body weight, and SFA levels, whereas reductions in VFA and total fat mass levels were somewhat maintained even after 12 weeks without treatment. Dapagliflozin led to decreases in VFA and, consequently, body weight after a short treatment period. However, these effects were largely reversed by the cessation of dapagliflozin, suggesting that this agent should be administered continuously to maintain clinical usefulness in overweight patients with type 2 diabetes.

Diets of differentially processed wheat alter ruminal fermentation parameters and microbial populations in beef cattle.

PubMed

Jiang, S Z; Yang, Z B; Yang, W R; Li, Z; Zhang, C Y; Liu, X M; Wan, F C

2015-11-01

The influences of differently processed wheat products on rumen fermentation, microbial populations, and serum biochemistry profiles in beef cattle were studied. Four ruminally cannulated Limousin × Luxi beef cattle (400 ± 10 kg) were used in the experiment with a 4 × 4 Latin square design. The experimental diets contained (on a DM basis) 60% corn silage as a forage source and 40% concentrate with 4 differently processed wheat products (extruded, pulverized, crushed, and rolled wheat). Concentrations of ruminal NH-N and microbial protein (MCP) in cattle fed crushed and rolled wheat were greater ( < 0.05) than the corresponding values in cattle fed pulverized and extruded wheat. Ruminal concentrations of total VFA and acetate and the ratio of acetate to propionate decreased ( < 0.05) with increased geometric mean particle size (geometric mean diameter) of processed wheat, except for extruded wheat; cattle fed extruded wheat had the lowest concentrations of total VFA and acetate among all treatments. The relative abundance of , , ciliated protozoa, and was lower in cattle fed the pulverized wheat diet than in the other 3 diets ( < 0.05), whereas the relative abundance of was decreased in cattle fed extruded wheat compared with cattle fed crushed and rolled wheat ( < 0.05). No treatment effect was obtained for serum enzyme activity and protein concentration ( > 0.05). Our findings suggest that the method of wheat processing could have a significant effect on ruminal fermentation parameters and microbial populations in beef cattle and that crushed and rolled processing is better in terms of ruminal NH-N and MCP content, acetate-to-propionate ratio, and relative abundance of rumen microorganisms.

Effect of monensin inclusion on intake, digestion, and ruminal fermentation parameters by Bos taurus indicus and Bos taurus taurus steers consuming bermudagrass hay.

PubMed

Bell, N L; Anderson, R C; Callaway, T R; Franco, M O; Sawyer, J E; Wickersham, T A

2017-06-01

Effects of monensin inclusion and cattle subspecies on utilization of bermudagrass hay (13.7% CP, 77.3% NDF, and 38.8% ADF) were evaluated using ruminally cannulated steers (5 [BI] and 5 [BT]; 398 kg BW). Subspecies were concurrently subjected to a 2-period, 2-treatment crossover design. Treatments were 0 (CON) or 200 mg·steer·d monensin (MON) in 0.91 kg dried distillers' grains with solubles. Periods were 70 d in length: 20 d of adaptation, 22 d of sample collection, and 28 d for withdrawal of treatment. Steers were group housed during adaptation and moved to individual covered pens for sampling. Hay, ort, and fecal grab samples were collected d 21 through 25 for determination of intake and digestion. Ruminal fluid was collected with a suction strainer 0, 2, 4, 8, and 12 h after feeding on d 42 for pH, VFA, and ruminal NH-N (RAN) analysis. Additionally, at h 2, ruminal fluid and contents were collected for determination of rate of NH production and CH production rate. No subspecies × monensin interactions were observed ( ≥ 0.12). Monensin had no effect ( ≥ 0.16) on intake or digestibility parameters. No subspecies effect ( ≥ 0.11) was observed for forage OM intake, total OM intake, or OM digestion. Total digestible OM intake tended to be greater ( = 0.06) for BT steers than for BI steers (14.0 vs. 12.2 g/kg BW). There was an effect of hour after feeding ( ≤ 0.01) on pH, total VFA, acetate:propionate ratio, and molar percent acetate and propionate. Total VFA concentration was greater ( = 0.01) in CON steers than in MON steers (66.5 vs. 62.0 m). Monensin decreased molar percent acetate ( = 0.02) from 72.5 to 71.2% and increased molar percent propionate ( < 0.01) from 16.9 to 18.7%, resulting in a reduced ( < 0.01) acetate:propionate ratio (from 4.34 to 3.85). Although not significantly ( = 0.19), monensin numerically reduced the CH production rate by 15.8%. Greater ( = 0.07) CH production rate tended to be observed in BI steers than in BT steers (21.4 vs. 16.6 μmol CH·mL·h, respectively). Monensin had no effect ( ≥ 0.32) on pH, RAN, or rate of NH production. A subspecies × hour after feeding interaction was observed for RAN, with BT having greater RAN at h 0 and 4, whereas BI had greater RAN at h 2, 8, and 12. Overall, monensin decreased the acetate:propionate ratio and total VFA concentration but had no effect on forage utilization. steers consumed less digestible OM and had a greater CH production rate compared with BT steers, suggesting BT were better able to utilize the available forage resource than BI.

Reducing methane production by supplementation of Terminalia chebula RETZ. containing tannins and saponins.

PubMed

Anantasook, Nirawan; Wanapat, Metha; Gunun, Pongsatorn; Cherdthong, Anusorn

2016-06-01

This study investigates the effects of Terminalia chebula Retz. meal supplementation on rumen fermentation and methane (CH4 ) production by using an in vitro gas technique. The experimental design was a completely randomized design (CRD) and the dietary treatments were T. chebula supplementation at 0, 4, 8, 12, 16 and 20 mg with 0.5 g of roughage and concentrate ratio at 60:40. The results revealed that cumulative gas production (96 h of incubation) were higher (P < 0.01) with T. chebula supplementation at 12, 16 and 20 mg than other treatments. However, in vitro dry matter degradability (IVDMD) and in vitro organic matter digestibility (IVOMD) were not significantly different among treatments (P > 0.05). The NH3 -N concentrations tended to quadratically increase with increasing levels of T. chebula in the diet. In addition, total volatile fatty acids (VFA) and propionate concentrations were increased (P < 0.01), while acetate concentration, acetate-to-propionate ratio, CH4 production and protozoal populations were decreased (P < 0.01) when supplemented with T. chebula at 8, 12 and 16 mg, respectively. Based on this study, it could be concluded that supplementation of T. chebula at 12 mg could improve rumen fermentation by reducing CH4 production and protozoa populations, thus improving in vitro gas production and VFA profiles. © 2015 Japanese Society of Animal Science.

Dynamics of changes in coplanar and indicator PCB in sewage sludge during mesophilic methane digestion.

PubMed

Rosińska, A; Karwowska, B

2017-02-05

Research was conducted, which aim was to evaluate the influence of mesophilic methane digestion on degradation of coplanar and indicator PCB in sewage sludge, and on dynamics of changes of these congeners during the process. For the research, sewage sludge from a municipal wastewater treatment plant were used. Mesophilic digestion was conducted at the temperature of 36°C±1°C. The anaerobic stabilization processes of sewage sludge occurred correctly what was confirmed by appropriate values of pH, content of volatile fatty acids (VFA) and ratio of VFA to alkalinity. Biodegradation of organic compounds in sewage sludge was confirmed by the decrease in total solids (by 26%) and volatile solids (by 36%). Up to the 3rd day of the digestion process no statistically significant differences in concentration of both coplanar and indicator PCB was observed. During the following days of the process, an increase in lower chlorinated PCB concentration was demonstrated and a decrease in concentration of higher chlorinated congeners (penta-, hexa-, and heptachlorobiphenyls). After the digestion, a decrease in higher chlorinated congener concentration was found. Significant degradation was demonstrated for coplanar PCB 169 (from 77.8 to 80.5%), and indicator PCB 180 (from 57.1 to 90.3%) and PCB 153 (from 60.4 to 79.2%). Copyright © 2016 Elsevier B.V. All rights reserved.

Reduced energy density of close-up diets decrease ruminal pH and increase concentration of volatile fatty acids postpartum in Holstein cows.

PubMed

Huang, Wenming; Tian, Yujia; Li, Shengli; Wu, Zhaohai; Cao, Zhijun

2017-11-01

The objective of this study was to determine the effect of reduced energy density of close-up diets on ruminal fermentation parameters in transition cows. Fourteen Holstein dry cows were blocked and assigned randomly to three groups fed a high energy density diet (HD, 1.62 Mcal of net energy for lactation (NE L )/kg dry matter (DM)), or a middle energy density diet (MD, 1.47 Mcal NE L /kg DM), or a low energy density diet (LD, 1.30 Mcal NE L /kg DM) prepartum, and were fed the same diet postpartum. The reduced energy density diets decreased the average dry matter intake (DMI) prepartum and tended to increase the DMI postpartum. The ruminal pH of the LD group was significantly higher prepartum and lower during the first week of lactation compared with the other two groups. The reduced energy density diet depressed the average ruminal concentration of propionate and butyrate prepartum, and increased the average concentration of total volatile fatty acids (VFA) postpartum. The LD group had higher populations of Butyrivibrio fibrisolvens and Ruminococcus flavefaciens relative to HD and MD groups on 7 days in milk. In conclusion, the cows fed reduced energy density diet prepartum had higher VFA concentration, but were more susceptible to subacute ruminal acidosis postpartum. © 2017 Japanese Society of Animal Science.

Enhancement of anaerobic biodegradability of flower stem wastes with vegetable wastes by co-hydrolysis.

PubMed

Zhang, Bo; He, Pinjing; Lü, Fan; Shao, Liming

2008-01-01

The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid (TS) conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids (VFA) and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes.

Effect of monensin on in vitro fermentation of silages and microbial protein synthesis.

PubMed

Wischer, Gerald; Boguhn, Jeannette; Steingaß, Herbert; Schollenberger, Margit; Hartung, Karin; Rodehutscord, Markus

2013-06-01

The objective of the study was to investigate the effects of monensin on silage fermentation and microbial net protein synthesis. In Experiment 1, monensin (0.5, 1, 2, 4, 6, or 10 µg) was added to syringes that contained 120 mg of grass silage (GS), grass silage and concentrate (GS + C), or maize silage (MS), resulting in concentrations of 4.2, 8.3, 16.7, 33.3, 50.0 and 83.3 mg monensin/kg feed. Samples were incubated for 24 h to determine the monensin concentration that resulted in the maximum reduction in methane production without effects on the total gas production. In Experiment 2, GS and GS + C were incubated in a rumen simulation technique (Rusitec) to assess the monensin effects (133 and 266 mg/kg feed) on the production of total gas, methane and volatile fatty acids (VFA), degradation of nutrients and microbial net protein synthesis. In Experiment 1, methane production was reduced without significant effects on the total gas production; the reductions were 17% (GS), 10% (GS + C) and 13% (MS) with 16.7 (GS), 50.0 (GS + C) and 33.3 (MS) mg monensin/kg feed. Monensin reduced the total gas and methane production in GS and GS + C in Experiment 2. Propionate production was enhanced by monensin, accompanied by a decrease in acetate production. Along with a reduction in crude protein (CP) degradation, monensin reduced the ammonia nitrogen concentration in the effluent of both treatments. While the protein produced by liquid-associated microbes increased with monensin, protein production by solid-associated microbes was reduced. Total microbial net protein synthesis increased in the presence of monensin. Monensin influenced the production of total gas, methane and VFA from the silages without an effect on the degradation of organic matter (OM). Different microbial fractions were affected differently by monensin supplementation. If monensin is used as a tool to reduce methane emission, the supplementation level must be carefully chosen to avoid negative effects on overall fermentation in the rumen.

Synergism and effect of high initial volatile fatty acid concentrations during food waste and pig manure anaerobic co-digestion.

PubMed

Dennehy, Conor; Lawlor, Peadar G; Croize, Thomas; Jiang, Yan; Morrison, Liam; Gardiner, Gillian E; Zhan, Xinmin

2016-10-01

Anaerobic co-digestion of food waste (FW) and pig manure (PM) was undertaken in batch mode at 37°C in order to identify and quantify the synergistic effects of co-digestion on the specific methane yield (SMY) and reaction kinetics. The effects of the high initial volatile fatty acid (VFA) concentrations in PM on synergy observed during co-digestion, and on kinetic modelling were investigated. PM to FW mixing ratios of 1/0, 4/1, 3/2, 2/3, 1/4 and 0/1 (VS basis) were examined. No VFA or ammonia inhibition was observed. The highest SMY of 521±29ml CH4/gVS was achieved at a PM/FW mixing ratio of 1/4. Synergy in terms of both reaction kinetics and SMY occurred at PM/FW mixing ratios of 3/2, 2/3 and 1/4. Initial VFA concentrations did not explain the synergy observed. Throughout the study the conversion of butyric acid was inhibited. Due to the high initial VFA content of PM, conventional first order and Gompertz models were inappropriate for determining reaction kinetics. A dual pooled first order model was found to provide the best fit for the data generated in this study. The optimal mixing ratio in terms of both reaction kinetics and SMY was found at a PM/FW mixing ratio of 1/4. Copyright © 2016 Elsevier Ltd. All rights reserved.

Conventional and thermophilic aerobic treatability of high strength oily pet food wastewater using membrane-coupled bioreactors.

PubMed

Kurian, R; Acharya, C; Nakhla, G; Bassi, A

2005-11-01

Although thermophilic treatment systems have recently gained considerable interest, limited information exists on the comparative performances of membrane-coupled bioreactors (MBR) at thermophilic and conventional conditions. In this study aerobic MBRs operating at room temperature (20 degrees C) and at lower thermophilic range (45 degrees C) were investigated for the treatment of dissolved air flotation (DAF) pretreated pet food wastewater. The particular wastewater is characterized by oil and grease (O & G) concentrations as high as 6 g/L, COD of 51 g/L, BOD of 16 g/L and volatile fatty acid (VFA) of 8.3 g/L. The performances of the two systems in terms of COD, BOD and O & G removal at varying hydraulic retention time (HRT) are compared. COD removal efficiencies in the thermophilic MBR varied from 75% to 98% and remained constant at 94% in the conventional MBR. The O & G removal efficiencies were 66-86% and 98% in the thermophilic and conventional MBR, respectively. Interestingly, high concentrations of VFA were recorded, equivalent to 50-73% of total COD, in the thermophilic MBR effluent. The observed yield in the thermophilic MBR was 40% of that observed in the conventional MBR.

The relationship between rumen acidosis resistance and expression of genes involved in regulation of intracellular pH and butyrate metabolism of ruminal epithelial cells in steers.

PubMed

Schlau, N; Guan, L L; Oba, M

2012-10-01

Past research has focused on the prevention and management of subacute rumen acidosis by manipulating the ration; however, the severity of acidosis varies even among animals fed a common high-grain diet. The objectives of this study were to compare the ruminal volatile fatty acid (VFA) profile and expression of genes involved in the metabolism of butyrate, the VFA most extensively metabolized by the ruminal epithelium, and intracellular pH regulation in ruminal epithelial cells between acidosis-resistant (AR) and acidosis-susceptible (AS) steers. Acidosis indexes (area per day under pH 5.8 divided by dry matter intake) were measured for 17 steers fed a common high-grain diet, and the 3 steers with the lowest (1.4 ± 1.2 pH∙min/kg) and the 3 with the highest values (23.9 ± 7.4 pH∙min/kg) were classified as AR and AS, respectively, and used in the subsequent study. The steers were force-fed a diet containing 85% grain at 60% of the expected daily intake (5.8 ± 0.8 and 5.6 ± 0.6 kg for AR and AS, respectively) within 30 min. Mean ruminal pH over the postprandial 6-h period was higher for AR compared with AS (6.02 vs. 5.55), and mean total VFA concentration was 74% for AR compared with AS (122 vs. 164 mM). Molar proportion of butyrate in the ruminal fluid was 139% higher for AR compared with AS (17.5 vs. 7.33 mol/100 mol of VFA). Expression of monocarboxylate cotransporter isoform 1, sodium hydrogen exchanger isoforms 1 and 2, and anion exchangers (downregulated in adenoma and putative anion exchanger, isoform 1) did not differ between AR and AS steers. However, expression of sodium hydrogen exchanger isoform 3, which imports Na(+) to the epithelial cell and exports H(+) to the rumen, was 176% higher in AR steers than in AS steers. Higher ruminal pH for AR might be partly due to a faster rate of VFA absorption, lower VFA production, or both. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effects of dietary concentration of wet distillers grains on performance by newly received beef cattle, in vitro gas production and volatile fatty acid concentrations, and in vitro dry matter disappearance.

PubMed

Smith, D R; Ponce, C H; Dilorenzo, N; Quinn, M J; May, M L; MacDonald, J C; Luebbe, M K; Bondurant, R G; Galyean, M L

2013-06-01

Three studies were designed to evaluate effects of wet distillers grains with solubles (WDGS) on health and performance of newly received beef cattle, in vitro gas production, molar proportions and total concentrations of VFA, and IVDMD. In Exp. 1 and 2, 219 (BW = 209 kg, SE = 2.2 kg; Exp. 1) and 200 beef steers (BW = 186 kg, SE = 3.2 kg; Exp. 2) were used in randomized complete block design receiving studies. The 4 dietary treatments (DM basis) were a 65% concentrate, steam-flaked corn (SFC)-based receiving diet without WDGS (CON) or diets that contained 12.5, 25.0, or 37.5% WDGS. There were no differences among the 4 receiving diets in BW (P ≥ 0.61), ADG (P ≥ 0.75), DMI (P ≥ 0.27), and G:F (P ≥ 0.35), or in the proportion of cattle treated for morbidity from bovine respiratory disease in either of the 2 experiments. In Exp. 3, in vitro methods were used to determine the effects of WDGS on IVDMD, total gas production, and molar proportions and total concentrations of VFA. Substrates used for the incubations contained the same major components as the diets used in Exp. 1, with ruminal fluid obtained from steers fed a 60% concentrate diet. Total gas production was less (P = 0.03) for the average of the 3 WDGS substrates than for CON, with a linear decrease (P = 0.01) in total gas production as WDGS concentration increased in the substrates. In contrast to gas production, IVDMD was greater for the average of the 3 WDGS concentrations vs. CON (P ≤ 0.05) at 6 and 12 h and increased (P ≤ 0.02) with increasing WDGS concentration at 6 (linear and quadratic) and 12 h (linear) of incubation. At 48 h, there was a quadratic effect (P = 0.05) on IVDMD, with the greatest value for 25% WDGS. Molar proportion of butyrate increased linearly (P < 0.01) as the concentration of WDGS increased in the substrate, and the average of the 3 substrates containing WDGS had a greater proportion of butyrate (P = 0.03) than CON. Performance data from Exp. 1 and 2 indicate that including WDGS in the SFC-based diets for newly received cattle can be an effective at concentrations up to 37.5% of the DM. In vivo measurements are needed to corroborate the in vitro fermentation changes noted with addition of WDGS.

Rumen fluid fermentation for enhancement of hydrolysis and acidification of grass clipping.

PubMed

Wang, Siqi; Zhang, Guangming; Zhang, Panyue; Ma, Xiaowen; Li, Fan; Zhang, Haibo; Tao, Xue; Ye, Junpei; Nabi, Mohammad

2018-08-15

Rumen fluid, formed in rumen of ruminants, includes a complex microbial population of bacteria, protozoa, fungi and archaea, and has high ability to degrade lignocellulosic biomass. In this study, rumen fluid was used to ferment grass clipping for enhancing the hydrolysis and acidification of organic matters. Results showed that strict anaerobic condition, higher grass clipping content and smaller particle size of grass clipping were beneficial to the hydrolysis and acidification of organics. The increase of SCOD and total VFA concentration respectively reached 24.9 and 10.2 g/L with a suitable grass clipping content of 5%, a particle size <0.150 mm, and a fermentation time of 48 h. The VFA production was mainly attributed to the degradation of cellulose and hemicellulose with a total solid reduction of 55.7%. Firmicutes and Fibrobacteres were the major contributors to the degradation of cellulose and hemicellulose. The activity of carboxymethyl cellulose enzyme (CMCase), cellobiase and xylanase reached 0.027, 0.176 and 0.180 U/ml, respectively. The rumen fluid microorganisms successfully enhanced the hydrolysis and acidification of grass clipping. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vortex Flow in the Right Atrium Surrogates Supraventricular Arrhythmia and Thrombus After Atriopulmonary Connection-Type Fontan Operation: Vortex Flow Analysis Using Conventional Cine Magnetic Resonance Imaging.

PubMed

Shiina, Yumi; Inai, Kei; Takahashi, Tatsunori; Shimomiya, Yamato; Ishizaki, Umiko; Fukushima, Kenji; Nagao, Michinobu

2018-02-01

We developed a novel imaging technique, designated as vortex flow (VF) mapping, which presents a vortex flow visually on conventional two-dimensional (2D) cine MRI. Using it, we assessed circumferential VF patterns and influences on RA thrombus and supraventricular tachycardia (SVT) in AP connection-type Fontan circulation. Retrospectively, we enrolled 27 consecutive patients (25.1 ± 9.2 years) and 7 age-matched controls who underwent cardiac MRI. Conventional cine images acquired using a 1.5-Tesla scanner were scanned for axial and coronal cross section of the RA. We developed "vortex flow mapping" to demonstrate the ratio of the circumferential voxel movement at each phase to the total movement throughout a cardiac cycle towards the RA center. The maximum ratio was used as a magnitude of vortex flow (MVF%) in RA cine imaging. We also measured percentages of strong and weak VF areas (VFA%). Furthermore, in 10 out of 27, we compared VF between previous CMR (3.8 ± 1.5 years ago) and latest CMR. Of the patients, 15 had cardiovascular complications (Group A); 12 did not (Group B). A transaxial image showed that strong VFA% in Group A was significantly smaller than that in Group B or controls. A coronal view revealed that strong VFA% was also smaller, and weak VFA% was larger in Group A than in Group B or controls (P < 0.05, and P < 0.05). Maximum MVF% in Group A was significantly smaller than in other groups (P < 0.001). Univariate logistic analyses revealed weak VFA% on a coronal image, and serum total bilirubin level as factors affecting cardiovascular complications (Odds ratio 1.14 and 66.1, 95% CI 1.004-1.30 and 1.59-2755.6, P values < 0.05 and < 0.05, respectively). Compared to the previous CMR, smaller maximum VMF%, smaller strong VFA%, and larger weak VFA% were identified in the latest CMR. Circumferentially weak VFA% on a coronal image can be one surrogate marker of SVT and thrombus in AP connection-type Fontan circulation. This simple VF assessment is clinically useful to detect blood stagnation.

Enhancement of Anaerobic Digestion to Treat Saline Sludge from Recirculating Aquaculture Systems

PubMed Central

Luo, Guo-zhi; Ma, Niannian; Li, Ping; Tan, Hong-xin; Liu, Wenchang

2015-01-01

The effectiveness of carbohydrate addition and the use of ultrasonication as a pretreatment for the mesophilic anaerobic digestion of saline aquacultural sludge was assessed. Analyses were conducted using an anaerobic sequencing batch reactor (ASBR), which included stopped gas production attributed to the saline inhibition. After increasing the C : N ratio, gas production was observed, and the total chemical oxygen demand (TCOD) removal efficiency increased from 75% to 80%. The TCOD removal efficiency of the sonication period was approximately 85%, compared to 75% for the untreated waste. Ultrasonication of aquaculture sludge was also found to enhance the gas production rate and the TCOD removal efficiency. The average volatile fatty acid (VFA) to alkalinity ratios ranged from 0.1 to 0.05, confirming the stability of the digesters. Furthermore, soluble chemical oxygen demand (SCOD), VFA, and PO4 3− concentrations increased in the effluents. There was a 114% greater gas generation during the ultrasonication period, with an average production of 0.08 g COD/L·day−1. PMID:26301258

Higher visceral fat area increases the risk of vitamin D insufficiency and deficiency in Chinese adults.

PubMed

Zhang, Meilin; Li, Ping; Zhu, Yufeng; Chang, Hong; Wang, Xuan; Liu, Weiqiao; Zhang, Yuwen; Huang, Guowei

2015-01-01

Visceral fat area (VFA), a novel sex-specific index for visceral fat obesity (VFO) might play a major role in the development of vitamin D deficiency. However, the association between VFA and vitamin D insufficiency and deficiency in Chinese population is less clear. The aim of this study was to explore the population-level association between VFA and vitamin D insufficiency and deficiency among Chinese men and women. This cross-sectional study involved 1105 adults aged 20-70 years living in Tianjin who were randomly selected and medically examined. All subjects underwent the bioelectrical impedance analysis (BIA) method to estimate the VFA. Serum 25-hydroxyvitamin D3 (25(OH) D3) level was assayed by the high-performance liquid chromatography (HPLC) method and defined insufficiency and deficiency following recommended cutoffs. The association between VFA and vitamin D insufficiency and deficiency was estimated using binary regression analysis. The total prevalence of vitamin D insufficiency (25(OH) D3: 20-29 μg/L) and deficiency (25(OH) D3 < 20 μg/L) were 26.60 % and 24.89 %, respectively. Significant negative association was observed for VFA with serum 25(OH) D3 levels in men and pre-menopausal women (P < 0.05), not in post-menopausal women (P > 0.05). Moreover, increased VFA was observed to be associated with higher vitamin D insufficiency or deficiency risk with a positive dose-response trend (P for trend < 0.001). As compared to individuals with the lowest VFA, those who had the highest VFA were at 4.9-fold risk of vitamin D insufficiency and deficiency [95 % confidence interval (95 % CI): 1.792-13.365] in men and 1.8-fold risk of vitamin D insufficiency and deficiency (95 % CI: 1.051-3.210) in pre-menopausal women, but not in post-menopausal women [odds ratio (OR) (95 % CI): 2.326(0.903-5.991)]. These results suggest that higher VFA increases the risk of vitamin D insufficiency and deficiency in men and pre-menopausal women, but not in post-menopausal women. VFA is a better and convenience surrogate marker for visceral adipose measurement and could be used in identifying the risk of vitamin D insufficiency and deficiency in routine health examination.

Dietary marker effects on fecal microbial ecology, fecal VFA, nutrient digestibility coefficients, and growth performance in finishing pigs

USDA-ARS?s Scientific Manuscript database

Use of indigestible markers such as Cr2O3, Fe2O3, and TiO2 are commonly used in animal studies to evaluate rate of passage and nutrient digestibility. Yet nothing is known relative to their potential impact on fecal microbial ecology and subsequent VFA generation. Two experiments utilizing a total o...

Effects of a specific blend of essential oils on apparent nutrient digestion, rumen fermentation and rumen microbial populations in sheep fed a 50:50 alfalfa hay:concentrate diet

PubMed Central

Khateri, N.; Azizi, O.; Jahani-Azizabadi, H.

2017-01-01

Objective An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results Ruminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion The results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites. PMID:28249376

Comparative Demonstration of Active and Semi-Passive In Situ Bioremediation Approaches for Perchlorate-Impacted Groundwater at Longhorn Army Ammunitions Plant

DTIC Science & Technology

2009-01-01

lactate, citric acid , or ethanol have been used in field applications. Biomass grows rapidly during the active phase when high concentrations of...6.7.4 Results of Oxidation Reduction Potential (ORP) Monitoring.............39 6.7.5 Results of Volatile Fatty Acids (VFA) Analysis...trinitrotoluene USEPA U.S. Environmental Protection Agency VC vinyl chloride VFA volatile fatty acid VOC volatile organic compounds Technical

Effect of cellobiose supplementation and dietary soluble fibre content on in vitro caecal fermentation of carbohydrate-rich substrates in rabbits.

PubMed

Ocasio-Vega, César; Abad-Guamán, Rodrigo; Delgado, Rebeca; Carabaño, Rosa; Carro, María Dolores; García, Javier

2018-06-01

The in vitro caecal fermentation of five substrates low in starch and protein content [d-(+)-glucose (GLU), d-cellobiose (CEL), sugar beet pectin (PEC), sugar beet pulp (SBP) and wheat straw (WS)] was investigated using soft faeces from rabbits receiving different levels of cellobiose and soluble fibre as inoculum. A total of 24 rabbits were supplemented 3 levels of cellobiose in the drinking water (0.0, 7.5, 15.0 g/l) and fed two experimental diets containing either low soluble fibre (LSF) or high soluble fibre (HSF) levels (84.0 and 130 g/kg dry matter). All substrates were subjected to a two-step pepsin/pancreatin in vitro pre-digestion, and the whole residue was used as substrate for the in vitro incubations. Gas production was measured until 144 h, and volatile fatty acid (VFA) production was determined at 24 h incubation. Experimental treatments did not affect SBP fermentation and had only a subtle influence on fermentation of WS and GLU. In contrast, cellobiose supplementation × donors' diet interactions were detected for most gas production parameters for CEL. Both the fractional gas production (k) and maximal gas production rates were linearly increased (p ≤ 0.042) and the initial delay in the onset of gas production (Lag) linearly decreased (p < 0.001) by cellobiose supplementation with the HSF inoculum, with no differences between the 7.5 and 15.0 doses. In contrast, with the LSF inoculum cellobiose supplementation only affected k values, which were quadratically increased (p = 0.043) and had maximal values for the 7.5 dose. A quadratic effect (p ≤ 0.018) of cellobiose supplementation was observed for total VFA production at 24 h when CEL and PEC were fermented, obtaining the maximal VFA production for the 7.5 dose of cellobiose. Total VFA production for CEL was greater with LSF than with HSF inoculum (20.7 vs. 12.9 mmol/l; p = 0.014), but the opposite was found for WS (3.97 vs. 6.21 mmol/l; p = 0.005). The use of LSF inoculum for CEL fermentation sharply reduced acetate (p = 0.001) and increased butyrate proportions (p ≤ 0.001) compared with the HSF inoculum. A positive relationship between total VFA caecal concentrations in rabbits receiving the same experimental treatments and in vitro values was only observed when WS was used as substrate (r = 0.90; p = 0.015; n = 6). The results suggest that experimental factors influenced the fermentative activity of caecal digesta, but the observed response differed with the incubated substrate, being the CEL the most affected.

Low ambient temperature elevates plasma triiodothyronine concentrations while reducing digesta mean retention time and methane yield in sheep.

PubMed

Barnett, M C; McFarlane, J R; Hegarty, R S

2015-06-01

Ruminant methane yield (MY) is positively correlated with mean retention time (MRT) of digesta. The hormone triiodothyronine (T3 ), which is negatively correlated with ambient temperature, is known to influence MRT. It was hypothesised that exposing sheep to low ambient temperatures would increase plasma T3 concentration and decrease MRT of digesta within the rumen of sheep, resulting in a reduction of MY. To test this hypothesis, six Merino sheep were exposed to two different ambient temperatures (cold treatment, 9 ± 1 °C; warm control 26 ± 1 °C). The effects on MY, digesta MRT, plasma T3 concentration, CO2 production, DM intake, DM digestibility, change in body weight (BW), rumen volatile fatty acid (VFA) concentrations, estimated microbial protein output, protozoa abundance, wool growth, water intake, urine output and rectal temperature were studied. Cold treatment resulted in a reduction in MY (p < 0.01); digesta MRT in rumen (p < 0.01), hindgut (p = 0.01) and total digestive tract (p < 0.01); protozoa abundance (p < 0.05); and water intake (p < 0.001). Exposure to cold temperature increased plasma T3 concentration (p < 0.05), CO2 production (p = 0.01), total VFA concentrations (p = 0.03) and estimated microbial output from the rumen (p = 0.03). The rate of wool growth increased (p < 0.01) due to cold treatment, but DM intake, DM digestibility and BW change were not affected. The results suggest that exposure of sheep to cold ambient temperatures reduces digesta retention time in the gastrointestinal tract, leading to a reduction in enteric methane yield. Further research is warranted to determine whether T3 could be used as an indirect selection tool for genetic selection of low enteric methane-producing ruminants. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Polyhydroxyalkanoate Production on Waste Water Treatment Plants: Process Scheme, Operating Conditions and Potential Analysis for German and European Municipal Waste Water Treatment Plants

PubMed Central

Pittmann, Timo; Steinmetz, Heidrun

2017-01-01

This work describes the production of polyhydroxyalkanoates (PHA) as a side stream process on a municipal waste water treatment plant (WWTP) and a subsequent analysis of the production potential in Germany and the European Union (EU). Therefore, tests with different types of sludge from a WWTP were investigated regarding their volatile fatty acids (VFA) production-potential. Afterwards, primary sludge was used as substrate to test a series of operating conditions (temperature, pH, retention time (RT) and withdrawal (WD)) in order to find suitable settings for a high and stable VFA production. In a second step, various tests regarding a high PHA production and stable PHA composition to determine the influence of substrate concentration, temperature, pH and cycle time of an installed feast/famine-regime were conducted. Experiments with a semi-continuous reactor operation showed that a short RT of 4 days and a small WD of 25% at pH = 6 and around 30 °C is preferable for a high VFA production rate (PR) of 1913 mgVFA/(L×d) and a stable VFA composition. A high PHA production up to 28.4% of cell dry weight (CDW) was reached at lower substrate concentration, 20 °C, neutral pH-value and a 24 h cycle time. A final step a potential analysis, based on the results and detailed data from German waste water treatment plants, showed that the theoretically possible production of biopolymers in Germany amounts to more than 19% of the 2016 worldwide biopolymer production. In addition, a profound estimation regarding the EU showed that in theory about 120% of the worldwide biopolymer production (in 2016) could be produced on European waste water treatment plants. PMID:28952533

A degradation model for high kitchen waste content municipal solid waste.

PubMed

Chen, Yunmin; Guo, Ruyang; Li, Yu-Chao; Liu, Hailong; Zhan, Tony Liangtong

2016-12-01

Municipal solid waste (MSW) in developing countries has a high content of kitchen waste (KW), and therefore contains large quantities of water and non-hollocellulose degradable organics. The degradation of high KW content MSW cannot be well simulated by the existing degradation models, which are mostly established for low KW content MSW in developed countries. This paper presents a two-stage anaerobic degradation model for high KW content MSW with degradations of hollocellulose, sugars, proteins and lipids considered. The ranges of the proportions of chemical compounds in MSW components are summarized with the recommended values given. Waste components are grouped into rapidly or slowly degradable categories in terms of the degradation rates under optimal water conditions for degradation. In the proposed model, the unionized VFA inhibitions of hydrolysis/acidogenesis and methanogenesis are considered as well as the pH inhibition of methanogenesis. Both modest and serious VFA inhibitions can be modeled by the proposed model. Default values for the parameters in the proposed method can be used for predictions of degradations of both low and high KW content MSW. The proposed model was verified by simulating two laboratory experiments, in which low and high KW content MSW were used, respectively. The simulated results are in good agreement with the measured data of the experiments. The results show that under low VFA concentrations, the pH inhibition of methanogenesis is the main inhibition to be considered, while the inhibitions of both hydrolysis/acidogenesis and methanogenesis caused by unionized VFA are significant under high VFA concentrations. The model is also used to compare the degradation behaviors of low and high KW content MSW under a favorable environmental condition, and it shows that the gas potential of high KW content MSW releases more quickly. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of lipid extraction on nutritive composition of winged bean (Psophocarpus tetragonolobus), rubber seed (Hevea brasiliensis), and tropical almond (Terminalia catappa).

PubMed

Jayanegara, Anuraga; Harahap, Rakhmad P; Rozi, Richard F; Nahrowi

2018-04-01

This experiment aimed to evaluate the nutritive composition and in vitro rumen fermentability and digestibility of intact and lipid-extracted winged bean, rubber seed, and tropical almond. Soybean, winged bean, rubber seed, and tropical almond were subjected to lipid extraction and chemical composition determination. Lipid extraction was performed through solvent extraction by Soxhlet procedure. Non-extracted and extracted samples of these materials were evaluated for in vitro rumen fermentation and digestibility assay using rumen: Buffer mixture. Parameters measured were gas production kinetics, total volatile fatty acid (VFA) concentration, ammonia, in vitro dry matter (IVDMD) and in vitro organic matter digestibility (IVOMD). Data were analyzed by analysis of variance and Duncan's multiple range test. Soybean, winged bean, rubber seed, and tropical almond contained high amounts of ether extract, i.e., above 20% DM. Crude protein contents of soybean, winged bean, rubber seed, and tropical almond increased by 17.7, 4.7, 55.2, and 126.5% after lipid extraction, respectively. In vitro gas production of intact winged bean was the highest among other materials at various time point intervals (p<0.05), followed by soybean > rubber seed > tropical almond. Extraction of lipid increased in vitro gas production, total VFA concentration, IVDMD, and IVOMD of soybean, winged bean, rubber seed, and tropical almond (p<0.05). After lipid extraction, all feed materials had similar IVDMD and IVOMD values. Lipid extraction improved the nutritional quality of winged bean, rubber seed, and tropical almond.

Yeast mixture of liquid beer and cassava pulp with rice straw for the growth of dairy heifers.

PubMed

Kamphayae, Sukanya; Kumagai, Hajime; Butcha, Patima; Ritruechai, Viroj; Udchachon, Supachai

2017-03-01

This study was conducted to determine the effects of mixtures of liquid brewer's yeast (LBY) and cassava pulp (CVP) with rice straw (RS) on feed intake, digestibility, rumen fermentation, and growth of dairy heifers. Sixteen Holstein crossbred heifers (13.8 ± 1.6 months old, 210 ± 23 kg body weight (BW)) were randomly allocated to four feeding treatments with four replications, which were 0:0:100 (RS), 0:70:30 (0%LBY), 20:50:30 (20%LBY), and 50:20:30 (50%LBY), respectively, for LBY/CVP/RS on a fresh matter basis. The heifers were offered conventional concentrate at 1.5% initial body weight daily and fed the treatment diets ad libitum. Average daily gain and feed intake were not significantly different among the treatments. The heifers fed 50%LBY had the highest crude protein (CP) intake and DM, OM, and CP digestibility (P < 0.05). The ruminal pH did not differ significantly among treatments, while NH 3 -N was the highest (P < 0.05) in 50%LBY. Total volatile fatty acid (VFA) concentrations and the molar proportion of each VFA were not significantly different among the treatments. Blood urea nitrogen concentrations of 50%LBY were the highest among the treatments (P < 0.05). The results indicated that 50%LBY improved CP digestibility.

The Influence of Feed Energy Density and a Formulated Additive on Rumen and Rectal Temperature in Hanwoo Steers

PubMed Central

Cho, Sangbuem; Mbiriri, David Tinotenda; Shim, Kwanseob; Lee, A-Leum; Oh, Seong-Jin; Yang, Jinho; Ryu, Chaehwa; Kim, Young-Hoon; Seo, Kang-Seok; Chae, Jung-Il; Oh, Young Kyoon; Choi, Nag-Jin

2014-01-01

The present study investigated the optimum blending condition of protected fat, choline and yeast culture for lowering of rumen temperature. The Box Benken experimental design, a fractional factorial arrangement, and response surface methodology were employed. The optimum blending condition was determined using the rumen simulated in vitro fermentation. An additive formulated on the optimum condition contained 50% of protected fat, 25% of yeast culture, 5% of choline, 7% of organic zinc, 6.5% of cinnamon, and 6.5% of stevioside. The feed additive was supplemented at a rate of 0.1% of diet (orchard grass:concentrate, 3:7) and compared with a control which had no additive. The treatment resulted in lower volatile fatty acid (VFA) concentration and biogas than the control. To investigate the effect of the optimized additive and feed energy levels on rumen and rectal temperatures, four rumen cannulated Hanwoo (Korean native beef breed) steers were in a 4×4 Latin square design. Energy levels were varied to low and high by altering the ratio of forage to concentrate in diet: low energy (6:4) and high energy (4:6). The additive was added at a rate of 0.1% of the diet. The following parameters were measured; feed intake, rumen and rectal temperatures, ruminal pH and VFA concentration. This study was conducted in an environmentally controlled house with temperature set at 30°C and relative humidity levels of 70%. Steers were housed individually in raised crates to facilitate collection of urine and feces. The adaptation period was for 14 days, 2 days for sampling and 7 days for resting the animals. The additive significantly reduced both rumen (p<0.01) and rectal temperatures (p<0.001) without depressed feed intake. There were interactions (p<0.01) between energy level and additive on ruminal temperature. Neither additive nor energy level had an effect on total VFA concentration. The additive however, significantly increased (p<0.01) propionate and subsequently had lower acetate:propionate (A/P) ratios than non-additive supplementation. High concentrate diets had significantly lower pH. Interactions between energy and additive were observed (p<0.01) in ammonia nitrogen production. Supplementation of diets with the additive resulted in lower rumen and rectal temperatures, hence the additive showed promise in alleviating undesirable effects of heat stress in cattle. PMID:25358327

The influence of feed energy density and a formulated additive on rumen and rectal temperature in hanwoo steers.

PubMed

Cho, Sangbuem; Mbiriri, David Tinotenda; Shim, Kwanseob; Lee, A-Leum; Oh, Seong-Jin; Yang, Jinho; Ryu, Chaehwa; Kim, Young-Hoon; Seo, Kang-Seok; Chae, Jung-Il; Oh, Young Kyoon; Choi, Nag-Jin

2014-11-01

The present study investigated the optimum blending condition of protected fat, choline and yeast culture for lowering of rumen temperature. The Box Benken experimental design, a fractional factorial arrangement, and response surface methodology were employed. The optimum blending condition was determined using the rumen simulated in vitro fermentation. An additive formulated on the optimum condition contained 50% of protected fat, 25% of yeast culture, 5% of choline, 7% of organic zinc, 6.5% of cinnamon, and 6.5% of stevioside. The feed additive was supplemented at a rate of 0.1% of diet (orchard grass:concentrate, 3:7) and compared with a control which had no additive. The treatment resulted in lower volatile fatty acid (VFA) concentration and biogas than the control. To investigate the effect of the optimized additive and feed energy levels on rumen and rectal temperatures, four rumen cannulated Hanwoo (Korean native beef breed) steers were in a 4×4 Latin square design. Energy levels were varied to low and high by altering the ratio of forage to concentrate in diet: low energy (6:4) and high energy (4:6). The additive was added at a rate of 0.1% of the diet. The following parameters were measured; feed intake, rumen and rectal temperatures, ruminal pH and VFA concentration. This study was conducted in an environmentally controlled house with temperature set at 30°C and relative humidity levels of 70%. Steers were housed individually in raised crates to facilitate collection of urine and feces. The adaptation period was for 14 days, 2 days for sampling and 7 days for resting the animals. The additive significantly reduced both rumen (p<0.01) and rectal temperatures (p<0.001) without depressed feed intake. There were interactions (p<0.01) between energy level and additive on ruminal temperature. Neither additive nor energy level had an effect on total VFA concentration. The additive however, significantly increased (p<0.01) propionate and subsequently had lower acetate:propionate (A/P) ratios than non-additive supplementation. High concentrate diets had significantly lower pH. Interactions between energy and additive were observed (p<0.01) in ammonia nitrogen production. Supplementation of diets with the additive resulted in lower rumen and rectal temperatures, hence the additive showed promise in alleviating undesirable effects of heat stress in cattle.

Physiological changes in rumen fermentation during acidosis induction and its control using a multivalent polyclonal antibody preparation in heifers.

PubMed

Blanch, M; Calsamiglia, S; DiLorenzo, N; DiCostanzo, A; Muetzel, S; Wallace, R J

2009-05-01

Physiological changes in rumen fermentation during acidosis induction and its control using a multivalent polyclonal antibody preparation (PAP) were studied in a completely randomized experiment using 12 crossbred heifers (452 +/- 20 kg of BW). Treatments were control (CTR) or PAP. The acidosis induction protocol consisted of 3 periods: 3 mo of 100% fescue hay fed for ad libitum intake, 10 d (from d 1 to 10 of the experiment) of adaptation to the treatment (100% forage feeding + 10 mL/d of PAP top-dressed to the treatment group), and 5 d (from d 11 to 15 of the experiment) of transition, which consisted of increasing the concentrate (16.5% CP) 2.5 kg/d up to 12.5 kg/d while maintaining ad libitum intake of fescue and providing 10 mL/d of PAP to the treated heifers. Concentrate feeding of 12.5 kg/d was maintained until heifers developed acidosis (from d 16 to 22 of the experiment). When an animal was considered acidotic, it was changed to a 50:50 forage:concentrate diet, monitored for 4 d, and removed from the experiment. Samples of ruminal fluid were collected before and 6 h after feeding to determine pH, VFA, lactate, protozoa counts, and DNA extraction for quantitative real-time PCR and denaturing gradient gel electrophoresis analyses. Only samples collected during adaptation to the treatment, at 3 and 1 d before acidosis, on the acidosis day, and at 1 and 4 d after acidosis were analyzed. Differences were declared at P < 0.05. Heifers (83% for CTR, and 50% for PAP) entered into acidosis 5.25 +/- 0.17 d after the beginning of the transition. The fermentation profile of animals with acidosis was similar between treatments. From 3 d before acidosis to acidosis day, decreases in pH and in acetate-to-propionate ratio and increases in total VFA, butyrate, and entodiniomorph counts were observed. However, the greatest concentrations of Streptococcus bovis and Megasphaera elsdenii (79 +/- 54 and 104 +/- 73 ng of DNA/mL of ruminal fluid, respectively) and a decrease in DMI (10.6 vs. 6.46 kg, respectively) were recorded 1 d after acidosis. Compared with CTR heifers, heifers fed PAP had greater pH before feeding on d 6 (6.70 vs. 6.11), 8 (6.54 vs. 5.95), and 9 (7.26 vs. 6.59) after the beginning of the feeding challenge. Heifers fed PAP tended to have greater total VFA concentrations than CTR (124 and 114 +/- 4.0 mM, respectively). These results indicate that PAP may be effective in controlling acidosis of heifers during a rapid transition to a high-concentrate diet.

Anaerobic co-digestion of food waste and landfill leachate in single-phase batch reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liao, Xiaofeng; Zhu, Shuangyan; Zhong, Delai

Highlights: • Anaerobic co-digestion strategy for food waste treatment at OLR 41.8 g VS/L. • A certain amount of raw leachate effectively relieved acidic inhibition. • The study showed that food waste was completely degraded. - Abstract: In order to investigate the effect of raw leachate on anaerobic digestion of food waste, co-digestions of food waste with raw leachate were carried out. A series of single-phase batch mesophilic (35 ± 1 °C) anaerobic digestions were performed at a food waste concentration of 41.8 g VS/L. The results showed that inhibition of biogas production by volatile fatty acids (VFA) occurred withoutmore » raw leachate addition. A certain amount of raw leachate in the reactors effectively relieved acidic inhibition caused by VFA accumulation, and the system maintained stable with methane yield of 369–466 mL/g VS. Total ammonia nitrogen introduced into the digestion systems with initial 2000–3000 mgNH{sub 4}–N/L not only replenished nitrogen for bacterial growth, but also formed a buffer system with VFA to maintain a delicate biochemical balance between the acidogenic and methanogenic microorganisms. UV spectroscopy and fluorescence excitation–emission matrix spectroscopy data showed that food waste was completely degraded. We concluded that using raw leachate for supplement water addition and pH modifier on anaerobic digestion of food waste was effective. An appropriate fraction of leachate could stimulate methanogenic activity and enhance biogas production.« less

Clinical impact of sarcopenia on prognosis in pancreatic ductal adenocarcinoma: A retrospective cohort study.

PubMed

Ninomiya, Go; Fujii, Tsutomu; Yamada, Suguru; Yabusaki, Norimitsu; Suzuki, Kojiro; Iwata, Naoki; Kanda, Mitsuro; Hayashi, Masamichi; Tanaka, Chie; Nakayama, Goro; Sugimoto, Hiroyuki; Koike, Masahiko; Fujiwara, Michitaka; Kodera, Yasuhiro

2017-03-01

To investigate the impact of the body composition such as skeletal muscle, visceral fat and body mass index (BMI) on patients with resected pancreatic ductal adenocarcinoma (PDAC). A total of 265 patients who underwent curative surgery for PDAC were examined in this study. The total skeletal muscle and fat tissue areas were evaluated in a single image obtained at the third lumber vertebra during a preoperative computed tomography (CT) scan. The patients were assigned to either the sarcopenia or non-sarcopenia group based on their skeletal muscle index (SMI) and classified into high visceral fat area (H-VFA) or low VFA (L-VFA) groups. The association of clinicopathological features and prognosis with the body composition were statistically analyzed. There were 170 patients (64.2%) with sarcopenia. The median survival time (MST) was 23.7 months for sarcopenia patients and 25.8 months for patients without sarcopenia. The MST was 24.4 months for H-VFA patients and 25.8 months for L-VFA patients. However, sarcopenia patients with BMI ≥22 exhibited significantly poorer survival than patients without sarcopenia (MST: 19.2 vs. 35.4 months, P = 0.025). There was a significant difference between patients with and without sarcopenia who did not receive chemotherapy (5-year survival rate: 0% vs. 68.3%, P = 0.003). The multivariate analysis revealed that tumor size, positive dissected peripancreatic tissue margin, and sarcopenia were independent prognostic factors. Sarcopenia is an independent prognostic factor in PDAC patients with a BMI ≥22. Therefore, evaluating skeletal muscle mass may be a simple and useful approach for predicting patient prognosis. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Using organic acids to control subacute ruminal acidosis and fermentation in feedlot cattle fed a high-grain diet.

PubMed

Vyas, D; Beauchemin, K A; Koenig, K M

2015-08-01

The objective of this study was to determine whether supplementing organic acids can prevent incidences of subacute ruminal acidosis (SARA) in beef heifers fed a diet consisting of 8% barley silage and 92% barley grain-based concentrate (DM basis). Ten ruminally cannulated Hereford crossbred heifers (484 ± 25 kg BW) were used in a replicated 5 × 5 Latin square design with 14-d periods including 10 d for dietary adaptation and 4 d for measurements. Dietary treatments included no supplementation (Control), low fumaric acid (61 g/d), high fumaric acid (125 g/d), low malic acid (59 g/d), and high malic acid (134 g/d). Organic acid supplementation had no effect on DMI ( = 0.77). Similarly, no effects were observed on mean ( = 0.74), minimum ( = 0.64), and maximum ( = 0.27) ruminal pH measured continuously for 48 h. Moreover, area under the curve for pH thresholds 6.2 ( = 0.97), 5.8 ( = 0.66), 5.5 ( = 0.55), and 5.2 ( = 0.93) was similar for all treatments. However, malic acid supplementation lowered the amount of time that ruminal pH was <6.2 compared with the Control ( = 0.02) and fumaric acid treatments ( < 0.01). No effects were observed on total VFA concentrations with organic acid supplementation ( = 0.98) compared with the Control, but greater total VFA concentrations were observed with fumaric acid compared with the malic acid treatments ( = 0.02). The population of total culturable bacteria 3 h after feeding was reduced with supplemental malic acid compared with the Control ( = 0.03) and fumaric acid treatments ( = 0.03). However, no effects were observed with organic acid supplementation on lactic acid-utilizing bacteria ( = 0.59). In conclusion, under the conditions of the present study, organic acid supplementation did not have any significant effects on ruminal fermentation parameters compared with the Control and were not effective in preventing SARA in beef cattle fed high-grain diets.

The effect of cellobiose on the health status of growing rabbits depends on the dietary level of soluble fiber.

PubMed

Ocasio-Vega, César; Delgado, Rebeca; Abad-Guamán, Rodrigo; Carabaño, Rosa; Carro, Maria Dolores; Menoyo, David; García, Javier

2018-05-04

The aim of this study was to examine whether the combination of dietary soluble fiber and cellobiose exerts a synergistic effect on growth performance, health status, fermentation traits, and immune response in rabbits. Six treatments in a 3 × 2 factorial arrangement were used: 3 cellobiose concentrations in drinking water (0.0, 7.5, and 15.0 g/L) × 2 dietary levels of soluble fiber (84.0 and 130 g/kg DM, for the low soluble fiber [LSF] and high soluble fiber [HSF] diets, respectively). A total of 318 young rabbits (53/treatment) were weaned at 34 d of age and had ad libitum access to feed and water. At 46 d of age, 9 rabbits/treatment were slaughtered and ileal and cecal digesta were collected to analyze VFA profile and the immune response in the cecal appendix mucosa. At 48 d of age, the cellobiose supplementation was withdrawn and the experimental diets were replaced by a standard commercial diet until 61 d of age. From 34 to 48 d of age, there was a linear increase of mortality with the level of cellobiose in the HSF group (0% vs. 17.1%; P = 0.017). In contrast, a quadratic effect of cellobiose level on mortality was observed in the LSF group, the rabbits offered 7.5-cellobiose showing the lowest mortality (5.7% vs. 21.4%; P = 0.030). Cellobiose level had a quadratic effect on ADFI, ADG, and G:F in this period (P ≤ 0.047), with the 7.5-cellobiose groups having the best growth performance. In contrast, only minor changes on these traits were observed from 48 d of age onwards. Cellobiose level influenced quadratically the ileal VFA concentrations (P = 0.014), showing the maximal value in the 7.5-cellobiose groups. In rabbits fed 7.5-cellobiose-LSF, a change of acetate to propionate, butyrate, and valerate was observed in the ileum. Increasing cellobiose levels reduced linearly cecal VFA concentrations in HSF fed rabbits, but no effect was detected in LSF groups (P = 0.046). The level of soluble fiber increased VFA concentrations in both the ileum (by 22%; P < 0.001), and the cecum (by 11%; P = 0.005). The relative gene expression of IL-6, IL-10, TNF-α, iNOS, MUC-1, and toll-like receptors (TLR-2 and TLR-4) in the cecal appendix increased linear and quadratically with increasing levels of cellobiose (P ≤ 0.063). In conclusion, in rabbits fed LSF diets, a dose of 7.5 g cellobiose/L drinking water would be recommended, whereas these levels of cellobiose supplementation should be avoided in rabbits fed HSF diets.

Selective simplification and reinforcement of microbial community in autothermal thermophilic aerobic digestion to enhancing stabilization process of sewage sludge by conditioning with ferric nitrate.

PubMed

Jin, Ningben; Shou, Zongqi; Yuan, Haiping; Lou, Ziyang; Zhu, Nanwen

2016-03-01

The effect of ferric nitrate on microbial community and enhancement of stabilization process for sewage sludge was investigated in autothermal thermophilic aerobic digestion. The disinhibition of volatile fatty acids (VFA) was obtained with alteration of individual VFA concentration order. Bacterial taxonomic identification by 454 high-throughput pyrosequencing found the dominant phylum Proteobacteria in non-dosing group was converted to phylum Firmicutes in dosing group after ferric nitrate added and simplification of bacteria phylotypes was achieved. The preponderant Tepidiphilus sp. vanished, and Symbiobacterium sp. and Tepidimicrobium sp. were the most advantageous phylotypes with conditioning of ferric nitrate. Consequently, biodegradable substances in dissolved organic matters increased, which contributed to the favorable environment for microbial metabolism and resulted in acceleration of sludge stabilization. Ultimately, higher stabilization level was achieved as ratio of soluble chemical oxygen demand to total chemical oxygen demand (TCOD) decreased while TCOD reduced as well in dosing group comparing to non-dosing group. Copyright © 2016 Elsevier Ltd. All rights reserved.

The relationship between visceral obesity and hepatic steatosis measured by controlled attenuation parameter

PubMed Central

Jung, Kyu Sik; Chon, Young Eun; Huh, Ji Hye; Park, Kyeong Hye; Chung, Jae Bock; Kim, Chang Oh; Han, Kwang-Hyub

2017-01-01

Background Nonalcoholic fatty liver disease (NAFLD) is closely related with obesity. However, obese subjects, generally represented by high BMI, do not always develop NAFLD. A number of possible causes of NAFLD have been studied, but the exact mechanism has not yet been elucidated. Methods A total of 304 consecutive subjects who underwent general health examinations including abdominal ultrasonography, transient elastography and abdominal fat computed tomography were prospectively enrolled. Significant steatosis was diagnosed by ultrasonography and controlled attenuation parameter (CAP) assessed by transient elastography. Results Visceral fat area (VFA) was significantly related to hepatic steatosis assessed by CAP, whereas body mass index (BMI) was related to CAP only in univariate analysis. In multiple logistic regression analysis, VFA (odds ratio [OR], 1.010; 95% confidence interval [CI], 1.001–1.019; P = 0.028) and triglycerides (TG) (OR, 1.006; 95% CI, 1.001–1.011; P = 0.022) were independent risk factors for significant hepatic steatosis. The risk of significant hepatic steatosis was higher in patients with higher VFA: the OR was 4.838 (P<0.001; 95% CI, 2.912–8.039) for 100200 cm2, compared to patients with a VFA ≤100 cm2. Conclusions Our data demonstrated that VFA and TG is significantly related to hepatic steatosis assessed by CAP not BMI. This finding suggests that surveillance for subjects with NAFLD should incorporate an indicator of visceral obesity, and not simply rely on BMI. PMID:29077769

Near-infrared spectroscopy (NIRS) for a real time monitoring of the biogas process.

PubMed

Stockl, Andrea; Lichti, Fabian

2018-01-01

In this research project Near-infrared spectroscopy (NIRS) was applied to monitor the content of specific process parameters in anaerobic digestion. A laboratory scaled biogas digester was constantly fed every four hours with maize- and grass silage to keep a base load with an organic loading rate (OLR) of 2.5 kg oDM/m 3  ∗ d. Daily impact loads with shredded wheat up to an OLR of 8 kg oDM/m 3  ∗ d were added in order to generate peaks at the parameters tested. The developed calibration models are capable to show changes in process parameters like volatile fatty acids (VFA), propionic acid, total inorganic carbon (TIC) and the ratio of the volatile fatty acids to the carbonate buffer (VFA/TIC). Based on the calibration of the models for VFA and TIC, the values could be predicted with an R 2 of 0.94 and 0.97, respectively. Moreover, the residual prediction deviations were 4.0 and 6.0 for VFA and TIC, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of feeding fresh cassava root with high-sulfur feed block on feed utilization, rumen fermentation, and blood metabolites in Thai native cattle.

PubMed

Cherdthong, Anusorn; Khonkhaeng, Benjamad; Seankamsorn, Anuthida; Supapong, Chanadol; Wanapat, Metha; Gunun, Nirawan; Gunun, Pongsatron; Chanjula, Pin; Polyorach, Sineenart

2018-03-14

The objective of this research was to evaluate the effect of feeding fresh cassava root (CR) along with a feed block containing high was to sulfur (FBS) on feed intake, digestibility, rumen fermentation, and blood thiocyanate concentration in Thai native beef cattle. Four Thai male native beef cattle, initial body weight (BW) of 130 + 20.0 kg, were used in this study. The experiments were randomly assigned according to a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. The main factors were supplemented fresh CR levels (1.0 and 1.5% BW) and across to a feed block supplemented with sulfur added 2% (FBS-2) and 4% (FBS-4). Intakes of rice straw, concentrate diets, and FBS were not affected by treatments. Intakes of CR, sulfur, and total intake were significantly altered by the FBS treatment. The apparent dry matter and organic matter digestibility coefficient were significantly higher in animals fed FBS-4 than in those fed FBS-2. The ruminal ammonia nitrogen concentration was not affected by treatment and ranged from 15.6 to 17.6 mg/dl. Populations of protozoa and fungal zoospores were similar across treatments, whereas the bacterial population was significantly different between sulfur levels in the feed block. Feeding CR with FBS did not change total volatile fatty acid (VFA) concentrations and VFA profiles except for the propionic acid concentration, which was higher in the group with CR supplementation at 1.5% BW. Cattle fed CR with FBS showed similar blood urea nitrogen concentration at various feeding times and overall. In contrast, CR supplementation at 1.5% BW with FBS-2 increased blood thiocyanate concentrations. Therefore, supplementation of FBS-2 was beneficial to Thai native beef cattle fed with 1.5% BW fresh CR as it improved digestibility and rumen fermentation presumed, because HCN from fresh cassava root was converted into thiocyanate, which is nontoxic to farm animals.

Cut-Off Values of Visceral Fat Area and Waist-to-Height Ratio: Diagnostic Criteria for Obesity-Related Disorders in Korean Children and Adolescents

PubMed Central

Lee, Kang-Kon; Park, Hye-Soon

2012-01-01

Purpose The aim of this study was to study the appropriate cut-off value of visceral fat area (VFA) and waist-to-height ratio (WTHR) which increase the risk of obesity-related disorders and to validate the diagnostic criteria of abdominal obesity and metabolic syndrome in Korean children and adolescents. Materials and Methods A total 314 subjects (131 boys and 183 girls) were included in this study. The subjects were selected from Korean children and adolescents who visited three University hospitals in Seoul and Uijeongbu from January 1999 to December 2009. All patients underwent computed tomography to measure VFA. Results The cut-off value of VFA associated with an increase risk of obesity-related disorder, according to the receiver operating characteristics curve, was 68.57 cm2 (sensitivity 59.8%, specificity 76.6%, p=0.01) for age between 10 to 15 years, and 71.10 cm2 (sensitivity 72.3%, specificity 76.5%, p<0.001) for age between 16 to 18 years. By simple regression analysis, the WTHR corresponding to a VFA of 68.57 cm2 was 0.54 for boys and 0.61 for girls, and the WTHR corresponding to a VFA of 71.10 cm2 was 0.51 for boys and 0.56 for girls (p=0.004 for boys, p<0.001 for girls). Conclusion Based on the results of this study, VFA which increases the risk of obesity-related disorders was 68.57 cm2 and the WTHR corresponding to this VFA was 0.54 for boys and 0.61 for girls age between 10-15 years, 71.70 cm2 and the WTHR 0.51 for boys and 0.56 for girls age between 16-18 years. For appropriate diagnostic criteria of abdominal obesity and obesity-related disorders in Korean children and adolescents, further studies are required. PMID:22187238

Associations of serum adipocyte fatty acid binding protein with body composition and fat distribution in nondiabetic Chinese women.

PubMed

Hao, Yaping; Ma, Xiaojing; Luo, Yuqi; Hu, Xiang; Pan, Xiaoping; Xiao, Yunfeng; Bao, Yuqian; Jia, Weiping

2015-05-01

Previous studies have demonstrated evidence of a positive relationship between serum adipocyte fatty acid binding protein (A-FABP) and obesity. However, associations of A-FABP with body composition and ectopic fat accumulation remain unclear. This study aimed to elucidate the effect of body composition, visceral fat area (VFA), and subcutaneous fat area (SFA) on serum A-FABP levels in a cohort of Chinese women without diabetes mellitus. A total of 2108 women without diabetes (760 premenopausal and 1348 postmenopausal women; age, 20-78 y) selected from the Shanghai Obesity Study were enrolled. VFA and SFA were measured by magnetic resonance imaging, and body composition was determined by bioelectrical impedance analysis. A high VFA was defined as ≥ 80 cm(2). A high SFA was defined as that above the 75th percentile cutoff point of the menopause-specific population, respectively. Serum A-FABP levels were higher in postmenopausal than premenopausal women (P < .001). Both premenopausal and postmenopausal women with an isolated high VFA had higher A-FABP levels than did those with an isolated high SFA (P = .017 and .002, respectively). In both body mass index (BMI) groups (< 25 and ≥ 25 kg/m(2)), women with a high VFA had higher serum A-FABP levels regardless of their menopausal status. Multiple stepwise regression analysis showed that A-FABP was independently associated with fat mass (Standardized β = 0.417 and 0.252 for premenopausal and postmenopausal status, respectively, both P < .001). Moreover, VFA was identified as an independent risk factor for A-FABP in postmenopausal women (Standardized β = 0.114, P = .001). Application of the same regression analyses model to the two BMI groups produced similar results in both BMI categories. Serum A-FABP levels were associated with fat mass, and were also influenced by VFA after menopause in Chinese women without diabetes mellitus.

Potential of tannin-rich plants for modulating ruminal microbes and ruminal fermentation in sheep.

PubMed

Rira, M; Morgavi, D P; Archimède, H; Marie-Magdeleine, C; Popova, M; Bousseboua, H; Doreau, M

2015-01-01

The objective of this work was to study nutritional strategies for decreasing methane production by ruminants fed tropical diets, combining in vitro and in vivo methods. The in vitro approach was used to evaluate the dose effect of condensed tannins (CT) contained in leaves of Gliricidia sepium, Leucaena leucocephala, and Manihot esculenta (39, 75, and 92 g CT/kg DM, respectively) on methane production and ruminal fermentation characteristics. Tannin-rich plants (TRP) were incubated for 24 h alone or mixed with a natural grassland hay based on Dichanthium spp. (control plant), so that proportions of TRP were 0, 0.25, 0.5, 0.75, and 1.0. Methane production, VFA concentration, and fermented OM decreased with increased proportions of TRP. Numerical differences on methane production and VFA concentration among TRP sources may be due to differences in their CT content, with greater effects for L. leucocephala and M. esculenta than for G. sepium. Independently of TRP, the response to increasing doses of CT was linear for methane production but quadratic for VFA concentration. As a result, at moderate tannin dose, methane decreased more than VFA. The in vivo trial was conducted to investigate the effect of TRP on different ruminal microbial populations. To this end, 8 rumen-cannulated sheep from 2 breeds (Texel and Blackbelly) were used in two 4 × 4 Latin square designs. Diets were fed ad libitum and were composed of the same feeds used for the in vitro trial: control plant alone or combined with pellets made from TRP leaves at 44% of the diet DM. Compared to TRP, concentration of Ruminococcus flavefaciens was greater for the control diet and concentration of Ruminococcus albus was least for the control diet. The methanogen population was greater for Texel than for Blackbelly. By contrast, TRP-containing diets did not affect protozoa or Fibrobacter succinogenes numbers. Hence, TRP showed potential for mitigating methane production by ruminants. These findings suggest that TRP fed as pellets could be used to decrease methane production.

Maximizing the production of butyric acid from food waste as a precursor for ABE-fermentation.

PubMed

Stein, Ullrich Heinz; Wimmer, B; Ortner, M; Fuchs, W; Bochmann, G

2017-11-15

The current study reports on the maximization of butyric acid production from food waste using a mixed microbial fermentation. In semi-continuous fermentations the effect of three different pH values (5.5, 7.0 and 9.0), three different temperatures (37°C, 55°C and 70°C) and two levels of hydraulic retention time (HRT, 2days and 6days) on the formation of butyric acid as well as total volatile fatty acid production (tVFA) were investigated. Overall, pH5.5 provided the lowest butyric acid concentrations regardless of the temperature and the HRT. At mesophilic temperature (37°C) alkaline conditions (pH9.0) lead to a strong incline of tVFA as well as butyric acid concentration probably due to a decreased solubilization of the substrate. However, most efficient in terms of butyric acid production was the fermentation conducted at 55°C and pH7 where a butyric acid concentrations of 10.55g/L (HRT 2days) and 13.00g/L (HRT 6days) were achieved. Additional experiments at 70°C showed declining butyric acid production. Increase of the HRT from 2days to 6days provided an increment of butyric acid concentration throughout almost all experimental settings. However, regarding volumetric productivity the increase in concentration does not compensate for the bigger reactor volume required to establish a higher HRT. At pH7 and 55°C the resulting volumetric production rates were 5.27g/L∗d at a HRT 2days and only 2.17g/L∗d at a HRT of 6days. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevalence of silent vertebral fractures detected by vertebral fracture assessment in young Portuguese men with hyperthyroidism.

PubMed

Barbosa, Ana Paula; Rui Mascarenhas, Mário; Silva, Carlos Francisco; Távora, Isabel; Bicho, Manuel; do Carmo, Isabel; de Oliveira, António Gouveia

2015-02-01

Hyperthyroidism is a risk factor for reduced bone mineral density (BMD) and osteoporotic fractures. Vertebral fracture assessment (VFA) by dual-energy X-ray absorptiometry (DXA) is a radiological method of visualization of the spine, which enables patient comfort and reduced radiation exposure. This study was carried out to evaluate BMD and the prevalence of silent vertebral fractures in young men with hyperthyroidism. We conducted a cross-sectional study in a group of Portuguese men aged up to 50 years and matched in hyperthyroidism (n=24) and control (n=24) groups. A group of 48 Portuguese men aged up to 50 years was divided and matched in hyperthyroidism (n=24) and control (n=24) groups. BMD (g/cm(2)) at L1-L4, hip, radius 33%, and whole body as well as the total body masses (kg) were studied by DXA. VFA was used to detect fractures and those were classified by Genant's semiquantitative method. No patient had previously been treated for hyperthyroidism, osteoporosis, or low bone mass. Adequate statistical tests were used. The mean age, height, and total fat mass were similar in both groups (P≥0.05). The total lean body mass and the mean BMD at lumbar spine, hip, and whole body were significantly decreased in the hyperthyroidism group. In this group, there was also a trend for an increased prevalence of reduced BMD/osteoporosis and osteoporotic vertebral fractures. The results obtained using VFA technology (confirmed by X-ray) suggest that the BMD changes in young men with nontreated hyperthyroidism may lead to the development of osteoporosis and vertebral fractures. This supports the pertinence of using VFA in the routine of osteoporosis assessment to detect silent fractures precociously and consider early treatment. © 2015 European Society of Endocrinology.

Effects of a spoilage yeast from silage on in vitro ruminal fermentation.

PubMed

Santos, M C; Lock, A L; Mechor, G D; Kung, L

2015-04-01

Feeding silages with high concentrations of yeasts from aerobic spoilage is often implicated as a cause of poor animal performance on dairies. Our objective was to determine if a commonly found spoilage yeast, isolated from silage, had the potential to alter in vitro ruminal fermentations. A single colony of Issatchenkia orientalis, isolated from high-moisture corn, was grown in selective medium. The yeast culture was purified and added to in vitro culture tubes containing a total mixed ration (43% concentrate, 43% corn silage, 11% alfalfa haylage, and 3% alfalfa hay on a dry matter basis), buffer, and ruminal fluid to achieve added theoretical final concentrations of 0 (CTR), 4.40 (low yeast; LY), 6.40 (medium yeast; MY), and 8.40 (high yeast; HY) log10 cfu of yeast/mL of in vitro fluid. Seven separate tubes were prepared for each treatment and each time point and incubated for 12 and 24h at 39 °C. At the end of the incubation period, samples were analyzed for pH, yeast number, neutral detergent fiber (NDF) digestibility, volatile fatty acids (VFA), and fatty acids (FA). We found that total viable yeast counts decreased for all treatments in in vitro incubations but were still relatively high (5.3 log10 cfu of yeasts/mL) for HY after 24h of incubation. Addition of HY resulted in a lower pH and higher concentration of total VFA in culture fluid compared with other treatments. Moreover, additions of MY and HY decreased in vitro NDF digestibility compared with CTR, and the effect was greatest for HY. Overall, the biohydrogenation of dietary unsaturated FA was not altered by addition of I. orientalis and decreased over time with an increase in the accumulation of saturated FA, especially palmitic and stearic acids. We conclude that addition of I. orientalis, especially at high levels, has the potential to reduce in vitro NDF digestion and alter other aspects of ruminal fermentations. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Synergism of Cattle and Bison Inoculum on Ruminal Fermentation and Select Bacterial Communities in an Artificial Rumen (Rusitec) Fed a Barley Straw Based Diet.

PubMed

Oss, Daniela B; Ribeiro, Gabriel O; Marcondes, Marcos I; Yang, WenZhu; Beauchemin, Karen A; Forster, Robert J; McAllister, Tim A

2016-01-01

This study evaluated the effect of increasing the proportion of bison relative to cattle inoculum on fermentation and microbial populations within an artificial rumen (Rusitec). The experiment was a completely randomized design with a factorial treatment structure (proportion cattle:bison inoculum; 0:100, 33:67, 67:33, and 100:0) replicated in two Rusitec apparatuses ( n = 8 fermenters). The experiment was 15 d with 8 d of adaptation and 7 d of sampling. Fermenters were fed a diet of 70:30 barley straw:concentrate (DM basis). True digestibility of DM was determined after 48 h of incubation from d 13 to 15, and daily ammonia (NH 3 ) and volatile fatty acid (VFA) production were measured on d 9-12. Protozoa counts were determined at d 9, 11, 13, and 15 and particle-associated bacteria (PAB) from d 13 to 15. Select bacterial populations in the PAB were measured using RT-qPCR. Fermenter was considered the experimental unit and day of sampling as a repeated measure. Increasing the proportion of bison inoculum resulted in a quadratic effect ( P < 0.05) on straw, concentrate and total true DM disappearance and on straw and total neutral detergent fiber (aNDF) disappearance, with greater disappearances observed with mixed inoculum. There were no effect of source or proportion of inoculum on ADF disappearance ( P > 0.05). Increasing bison inoculum linearly increased ( P < 0.05) concentrate aNDF disappearance, total and concentrate N disappearance as well as total daily VFA and acetate production. A positive quadratic response ( P < 0.05) was observed for daily NH 3 -N, propionate, butyrate, valerate, isovalerate and isobutyrate production, as well as the acetate:propionate ratio. Increasing the proportion of bison inoculum linearly increased ( P < 0.05) total protozoa numbers. No effects were observed on pH, total gas and methane production, microbial N synthesis, or copies of 16S rRNA associated with total bacteria, Selenomonas ruminantium or Prevotella bryantii . Increasing bison inoculum had a quadratic effect ( P < 0.05) on Fibrobacter succinogenes , and tended to linearly ( P < 0.10) increase Ruminococcus flavefaciens and decrease ( P < 0.05) Ruminococcus albus copy numbers. In conclusion, bison inoculum increased the degradation of feed protein and fiber. A mixture of cattle and bison rumen inoculum acted synergistically, increasing the DM and aNDF disappearance of barley straw.

Synergism of Cattle and Bison Inoculum on Ruminal Fermentation and Select Bacterial Communities in an Artificial Rumen (Rusitec) Fed a Barley Straw Based Diet

PubMed Central

Oss, Daniela B.; Ribeiro, Gabriel O.; Marcondes, Marcos I.; Yang, WenZhu; Beauchemin, Karen A.; Forster, Robert J.; McAllister, Tim A.

2016-01-01

This study evaluated the effect of increasing the proportion of bison relative to cattle inoculum on fermentation and microbial populations within an artificial rumen (Rusitec). The experiment was a completely randomized design with a factorial treatment structure (proportion cattle:bison inoculum; 0:100, 33:67, 67:33, and 100:0) replicated in two Rusitec apparatuses (n = 8 fermenters). The experiment was 15 d with 8 d of adaptation and 7 d of sampling. Fermenters were fed a diet of 70:30 barley straw:concentrate (DM basis). True digestibility of DM was determined after 48 h of incubation from d 13 to 15, and daily ammonia (NH3) and volatile fatty acid (VFA) production were measured on d 9–12. Protozoa counts were determined at d 9, 11, 13, and 15 and particle-associated bacteria (PAB) from d 13 to 15. Select bacterial populations in the PAB were measured using RT-qPCR. Fermenter was considered the experimental unit and day of sampling as a repeated measure. Increasing the proportion of bison inoculum resulted in a quadratic effect (P < 0.05) on straw, concentrate and total true DM disappearance and on straw and total neutral detergent fiber (aNDF) disappearance, with greater disappearances observed with mixed inoculum. There were no effect of source or proportion of inoculum on ADF disappearance (P > 0.05). Increasing bison inoculum linearly increased (P < 0.05) concentrate aNDF disappearance, total and concentrate N disappearance as well as total daily VFA and acetate production. A positive quadratic response (P < 0.05) was observed for daily NH3-N, propionate, butyrate, valerate, isovalerate and isobutyrate production, as well as the acetate:propionate ratio. Increasing the proportion of bison inoculum linearly increased (P < 0.05) total protozoa numbers. No effects were observed on pH, total gas and methane production, microbial N synthesis, or copies of 16S rRNA associated with total bacteria, Selenomonas ruminantium or Prevotella bryantii. Increasing bison inoculum had a quadratic effect (P < 0.05) on Fibrobacter succinogenes, and tended to linearly (P < 0.10) increase Ruminococcus flavefaciens and decrease (P < 0.05) Ruminococcus albus copy numbers. In conclusion, bison inoculum increased the degradation of feed protein and fiber. A mixture of cattle and bison rumen inoculum acted synergistically, increasing the DM and aNDF disappearance of barley straw. PMID:28018336

Effect of COD/SO4(2-) ratio on anaerobic treatment of landfill leachate during the start-up period.

PubMed

Yilmaz, Tuba; Erdirencelebi, Dilek; Berktay, Ali

2012-01-01

This study investigates the performance of an anaerobic baffled reactor (ABR) during the start-up period of raw young landfill leachate treatment at two chemical oxygen demand (COD) to SO4(2-) ratios of 20 and 4. The reactor was operated at ambient temperature and low organic loading rates (0.52, 0.76 and 1.05 kg COD/m3 per day). During the study, sulfate-reducing bacteria (SRB) activity increased at the lower ratio of COD/SO4(2-) producing higher levels of sulfide and alkalinity. The dissolved sulfide concentration reached an inhibitory level above 250 mg/L, which caused a sharp reduction in the total COD removal efficiency from 77-80% to 32%. Total volatile fatty acid (TVFA) production proceeded at a constant level despite increased organic loading. As the effluent total and organic COD concentrations increased, the inhibitory effect of the inborn sulfide was correlated to the limitation experienced in the hydrolysis/acidogenesis stages, and thus VFA production and organic matter removal.

Acute exposure to ergot alkaloids from endophyte-infected tall fescue does not alter absorptive or barrier function of the isolated bovine ruminal epithelium.

PubMed

Foote, A P; Penner, G B; Walpole, M E; Klotz, J L; Brown, K R; Bush, L P; Harmon, D L

2014-07-01

Ergot alkaloids in endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum) have been shown to cause a reduction in blood flow to the rumen epithelium as well as a decrease in volatile fatty acids (VFA) absorption from the washed rumen of steers. Previous data also indicates that incubating an extract of endophyte-infected tall fescue seed causes an increase in the amount of VFA absorbed per unit of blood flow, which could result from an alteration in the absorptive or barrier function of the rumen epithelium. An experiment was conducted to determine the acute effects of an endophyte-infected tall fescue seed extract (EXT) on total, passive or facilitated acetate and butyrate flux across the isolated bovine rumen as well as the barrier function measured by inulin flux and tissue conductance (G t ). Flux of ergovaline across the rumen epithelium was also evaluated. Rumen tissue from the caudal dorsal sac of Holstein steers (n=6), fed a common diet, was collected and isolated shortly after slaughter and mounted between two halves of Ussing chambers. In vitro treatments included vehicle control (80% methanol, 0.5% of total volume), Low EXT (50 ng ergovaline/ml) and High EXT (250 ng ergovaline/ml). Results indicate that there is no effect of acute exposure to ergot alkaloids on total, passive or facilitated flux of acetate or butyrate across the isolate bovine rumen epithelium (P>0.51). Inulin flux (P=0.16) and G t (P>0.17) were not affected by EXT treatment, indicating no alteration in barrier function due to acute ergot alkaloid exposure. Ergovaline was detected in the serosal buffer of the High EXT treatment indicating that the flux rate is ~0.25 to 0.44 ng/cm2 per hour. Data indicate that specific pathways for VFA absorption and barrier function of the rumen epithelium are not affected by acute exposure to ergot alkaloids from tall fescue at the concentrations tested. Ergovaline has the potential to be absorbed from the rumen of cattle that could contribute to reduced blood flow and motility and lead to reduced growth rates of cattle.

Effects of forage:concentrate ratio and forage type on apparent digestibility, ruminal fermentation, and microbial growth in goats.

PubMed

Cantalapiedra-Hijar, G; Yáñez-Ruiz, D R; Martín-García, A I; Molina-Alcaide, E

2009-02-01

The effects of forage type and forage:concentrate ratio (F:C) on apparent nutrient digestibility, ruminal fermentation, and microbial growth were investigated in goats. A comparison between liquid (LAB) and solid (SAB)-associated bacteria to estimate microbial N flow (MNF) from urinary purine derivative excretion was also examined. Treatments were a 2 x 2 factorial arrangement of forage type (grass hay vs. alfalfa hay) and high vs. low F:C (70:30 and 30:70, respectively). Four ruminally cannulated goats were fed, at maintenance intake, 4 experimental diets according to a 4 x 4 Latin square design. High-concentrate diets resulted in greater (P < 0.001) nutrient digestibility except for ADF. However, CP digestibility increased (P < 0.001) only for the high-concentrate diets including grass hay. Likewise, N retention, ruminal NH(3)-N concentration, and urinary excretion of purine derivatives increased (P < 0.05) with increasing concentrate in animals fed diets based on grass hay (0.23 vs. 0.13 g of retained N/g of digested N, 30.1 vs. 12.9 mg of NH(3)-N/100 mL, and 11.5 vs. 8.40 mmol/d, respectively), but not (P > 0.05) when diets included alfalfa hay. Total protozoa numbers and holotricha proportion were greater and less (P < 0.001), respectively, in high- than in low-concentrate diets. The F:C affected (P < 0.001) ruminal pH but not total VFA concentration (P = 0.12). Ammonia-N concentration was similar (P = 0.13) over time, whereas pH, VFA concentration, and protozoa numbers differed (P < 0.001) among diets. Estimated MNF was strongly influenced by using either the purine bases:N ratio obtained in our experimental conditions or values reported in the literature for small ruminants. There was a F:C effect (P = 0.006) on MNF estimated from LAB but not from SAB. The effect of F:C shifting from 70:30 to 30:70 in goat diets depends on the type of forage used. The MNF measured in goats fed different diets was influenced by the bacterial pellet (LAB or SAB). In addition, the purine bases:N ratio values found were different from those reported in the literature, which underlines the need for these variables to be analyzed directly in pellets isolated from specific animals and experimental conditions.

In vitro methane and gas production with inocula from cows and goats fed an identical diet.

PubMed

Mengistu, Genet; Hendriks, Wouter H; Pellikaan, Wilbert F

2018-03-01

Fermentative capacity among ruminants can differ depending on the type of ruminant species and the substrate fermented. The aim was to compare in vitro cow and goat rumen inocula in terms of methane (CH 4 ) and gas production (GP), fermentation kinetics and 72 h volatile fatty acids (VFA) production using the browse species Acacia etbaica, Capparis tomentosa, Dichrostachys cinerea, Rhus natalensis, freeze-dried maize silage and grass silage, and a concentrate as substrates. Total GP, CH 4 and VFA were higher (P ≤ 0.008) in goat inoculum than cows across substrates. The half-time for asymptotic GP was lower (P < 0.0001) in phase 1 and higher (P < 0.012) in phase 2, and the maximum rate of GP was higher (P < 0.0001) in phase 1 and phase 3 (P < 0.0001) in goats compared to cows. Methane production and as a percentage of total GP was higher (P < 0.0001) and the half-time tended (P = 0.059) to be at a later time for goats compared to cows. Goat inoculum showed higher fermentative activity with a concomitant higher CH 4 production compared to cows. This difference highlights the ability of goats to better utilise browse species and other roughage types. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Symptoms related to glaucomatous visual field abnormalities among male Japanese workers in a population-based setting.

PubMed

Tatemichi, Masayuki; Nakano, Tadashi; Hayashi, Takeshi; Tanaka, Katsutoshi; Hiro, Hisanori; Miyamoto, Toshiaki; Aratake, Miho; Nishinoue, Norihide; Yamazaki, Akira; Nakadate, Toshio; Sugita, Minoru

2012-09-01

To identify symptoms potentially related to glaucomatous visual field abnormalities (VFAs) in a population-based setting, and to assess the applicability of using these symptoms to identify persons at risk of developing glaucoma. In this study, 10,214 Japanese male general workers (mean age, 45.3±8.8 years) filled out a self-administered questionnaire and underwent frequency doubling technology (FDT) perimetry testing. The questionnaire inquired about whether the participant was suffering from any of nine symptoms, with scores for each response graded on a four-item Likert scale: 0 (none), 1 (rarely), 2 (sometimes), and 3 (always). Results from the questionnaire were compared among three groups: participants without any VFAs (9767), participants with VFAs as determined by the FDT test (FDT-VFA; 447), and 227 participants (of the 447 FDT-VFA participants) with glaucomatous VFAs who were newly diagnosed by ophthalmologic examinations. The mean summed scores for the total items were significantly (p<0.01) higher in FDT- and glaucomatous VFA groups than in normal subjects. In particular, responses citing the symptoms 'feeling of something in the front of the eye' and 'feeling of hardness to see in dark places' were significantly (p<0.05) more frequent in subjects with FDT- and glaucomatous VFAs than among normal participants. However, the respective areas under the receiver operating characteristic curve of summed scores for the nine total items and for the two items which showed significant differences for the glaucoma groups were 0.57 (95% confidence interval=0.53-0.60) and 0.58 (95% confidence interval=0.54-0.61). Although the symptoms 'feeling of hardness to see in dark places' and 'feeling of something in the front of the eye' could be associated with glaucomatous VFA in a population-based setting, inquiring about symptoms is of little aid in identifying subjects with glaucomatous VFA as a strategy for public health. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

Anaerobic digestion of swine manure under natural zeolite addition: VFA evolution, cation variation, and related microbial diversity.

PubMed

Lin, Lin; Wan, Chunli; Liu, Xiang; Lei, Zhongfang; Lee, Duu-Jong; Zhang, Yi; Tay, Joo Hwa; Zhang, Zhenya

2013-12-01

Batch experiments were carried out on anaerobic digestion of swine manure under 10 % of total solids and 60 g/L of zeolite addition at 35 °C. Four distinctive volatile fatty acid (VFAs) evolution stages were observed during the anaerobic process, i.e., VFA accumulation, acetic acid (HAc) and butyric acid (HBu) utilization, propionic acid (HPr) and valeric acid (HVa) degradation, and VFA depletion. Large decreases in HAc/HBu and HPr/HVa occurred respectively at the first and second biogas peaks. Biogas yield increased by 20 % after zeolite addition, about 356 mL/g VSadded with accelerated soluble chemical oxygen demand degradation and VFA (especially HPr and HBu) consumption in addition to a shortened lag phase between the two biogas peaks. Compared with Ca(2+) and Mg(2+) (100-300 mg/L) released from zeolite, simultaneous K(+) and NH4 (+) (580-600 mg/L) adsorptions onto zeolite particles contributed more to the enhanced biogasification, resulting in alleviated inhibition effects of ammonium on acidogenesis and methanogenesis, respectively. All the identified anaerobes could be grouped into Bacteroidetes and Firmicutes, and zeolite addition had no significant influence on the microbial biodiversity in this study.

Acidogenic fermentation of Scenedesmus sp.-AMDD: Comparison of volatile fatty acids yields between mesophilic and thermophilic conditions.

PubMed

Gruhn, Marvin; Frigon, Jean-Claude; Guiot, Serge R

2016-01-01

This study compared the acidogenic fermentation of Scenedesmus sp.-AMDD at laboratory-scale, under mesophilic (35°C) and thermophilic conditions (55°C). Preliminary batch tests were performed to evaluate best conditions for volatile fatty acid (VFA) production from microalgal biomass, with respect to the inoculum, pH and nutrients. The use of bovine manure as inoculum, the operating pH of 4.5 and the addition of a nutrient mix, resulted in a high VFA production of up to 222mgg(-1) total volatile solid (TVS), with a butyrate share of 27%. Both digesters displayed similar hydrolytic activity with 0.38±0.02 and 0.42±0.03 g soluble chemical oxygen demand (COD)g(-1) TVS for the digesters operated at 35 and 55°C, respectively. Mesophilic conditions were more favorable for VFA production, which reached 171±5, compared to 88±12 mg soluble CODg(-1) TVS added under thermophilic conditions (94% more). It was shown that in both digesters, butyrate was the predominant VFA. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Effects of bacterial direct-fed microbials on ruminal characteristics, methane emission, and milk fatty acid composition in cows fed high- or low-starch diets.

PubMed

Philippeau, C; Lettat, A; Martin, C; Silberberg, M; Morgavi, D P; Ferlay, A; Berger, C; Nozière, P

2017-04-01

This study investigated the effects of bacterial direct-fed microbials (DFM) on ruminal fermentation and microbial characteristics, methane (CH 4 ) emission, diet digestibility, and milk fatty acid (FA) composition in dairy cows fed diets formulated to induce different ruminal volatile fatty acid (VFA) profiles. Eight ruminally cannulated dairy cows were divided into 2 groups based on parity, days in milk, milk production, and body weight. Cows in each group were fed either a high-starch (38%, HS) or a low-starch (2%, LS) diet in a 55:45 forage-to-concentrate ratio on a dry matter (DM) basis. For each diet, cows were randomly assigned to 1 of 4 treatments in a Latin square design of (1) control (CON); (2) Propionibacterium P63 (P63); (3) P63 plus Lactobacillus plantarum 115 (P63+Lp); (4) P63 plus Lactobacillus rhamnosus 32 (P63+Lr). Strains of DFM were administered at 10 10 cfu/d. Methane emission (using the sulfur hexafluoride tracer technique), total-tract digestibility, dry matter intake, and milk production and composition were quantified in wk 3. Ruminal fermentation and microbial characteristics were measured in wk 4. Data were analyzed using the mixed procedure of SAS (SAS Institute Inc., Cary, NC). The 2 diets induced different ruminal VFA profiles, with a greater proportion of propionate at the expense of acetate and butyrate for the HS diet. Greater concentrations of total bacteria and selected bacterial species of methanogenic Archaea were reported for the HS diet, whereas the protozoa concentration in HS decreased. For both diets, bacterial DFM supplementation raised ruminal pH (+0.18 pH units, on average) compared with CON. Irrespective of diet, P63+Lp and P63+Lr increased ruminal cellulase activity (3.8-fold, on average) compared with CON, but this effect was not associated with variations in ruminal microbial numbers. Irrespective of diet, no effect of bacterial DFM on ruminal VFA was observed. For the LS diet, supplementing cows with P63+Lr tended to decrease CH 4 emission (26.5%, on average, when expressed per kilogram of milk or 4% fat-corrected milk). Only P63 supplementation to cows fed the HS diet affected the concentration of some milk FA, such as cis isomers of 18:1 and intermediates of ruminal biohydrogenation of polyunsaturated FA. Overall, bacterial DFM could be useful to stabilize ruminal pH. Their effects on CH 4 production mitigation and milk FA profile depended on DFM strain and diet and should be confirmed under a greater variation of dietary conditions. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Technical note: A device for obtaining time-integrated samples of ruminal fluid

USGS Publications Warehouse

Corley, R. N.; Murphy, M.R.; Lucena, J.; Panno, S.V.

1999-01-01

A device was adapted to allow for time-integrated sampling of fluid from the rumen via a cannula. The sampler consisted of a cup-shaped ceramic filter positioned in the ventral rumen of a cannulated cow and attached to a tube through which fluid entering the filter was removed continuously using a peristaltic pump. Rate of ruminal fluid removal using the device was monitored over two 36-h periods (at 6-h intervals) and was not affected (P > .05) by time, indicating that the system was not susceptible to clogging during this period. Two cows having ad libitum access to a totally mixed ration were used in a split-block design to evaluate the utility of the system for obtaining time-integrated samples of ruminal fluid. Ruminal fluid VFA concentration and pattern in samples collected in two replicated 8-h periods by the time-integrated sampler (at 1-h intervals) were compared with composite samples collected using a conventional suction-strainer device (at 30-min intervals). Each 8-h collection period started 2 h before or 6 h after feeding. Results indicated that total VFA concentration was not affected (P > .05) by the sampling method. Volatile fatty acid patterns were likewise unaffected (P > .05) except that acetate was 2.5% higher (P < .05) in samples collected 2 h before feeding and valerate was 5% higher (P < .05) in samples collected 6 h after feeding by the suction-strainer device. Although significant, these differences were not considered physiologically important. We concluded that use of the ceramic filter improved the sampling of ruminal fluid by simplifying the technique and allowing time-integrated samples to be obtained.

Effects of free ammonia on volatile fatty acid accumulation and process performance in the anaerobic digestion of two typical bio-wastes.

PubMed

Shi, Xuchuan; Lin, Jia; Zuo, Jiane; Li, Peng; Li, Xiaoxia; Guo, Xianglin

2017-05-01

The effect of free ammonia on volatile fatty acid (VFA) accumulation and process instability was studied using a lab-scale anaerobic digester fed by two typical bio-wastes: fruit and vegetable waste (FVW) and food waste (FW) at 35°C with an organic loading rate (OLR) of 3.0kg VS/(m 3 ·day). The inhibitory effects of free ammonia on methanogenesis were observed due to the low C/N ratio of each substrate (15.6 and 17.2, respectively). A high concentration of free ammonia inhibited methanogenesis resulting in the accumulation of VFAs and a low methane yield. In the inhibited state, acetate accumulated more quickly than propionate and was the main type of accumulated VFA. The co-accumulation of ammonia and VFAs led to an "inhibited steady state" and the ammonia was the main inhibitory substance that triggered the process perturbation. By statistical significance test and VFA fluctuation ratio analysis, the free ammonia inhibition threshold was identified as 45mg/L. Moreover, propionate, iso-butyrate and valerate were determined to be the three most sensitive VFA parameters that were subject to ammonia inhibition. Copyright © 2016. Published by Elsevier B.V.

Anaerobic digestion of pig and dairy manure under photo-dark fermentation condition.

PubMed

Yin, Dongxue; Liu, Wei; Zhai, Ningning; Yang, Gaihe; Wang, Xiaojiao; Feng, Yongzhong; Ren, Guangxin

2014-08-01

Anaerobic digestion (AD) with livestock manure is a promising way for biogas production. This work presents the influence of photo-dark fermentation on biogas production of pig manure (PM) and dairy manure (DM). All sets were conducted with temperature 35 ± 2 °C and total solid concentrations 8%: PM₁ and DM₁ in transparent reactor under sunlight for photo-dark fermentation, and PM₂ and DM₂ in non-transparent reactor for dark fermentation. DM₂ had the best cumulative biogas production (CBP) of 15,447.5 mL, followed by PM₁ (15,020 mL) with stable pH and low total ammonium nitrogen (TAN) concentration (1384.99 mg/L), and DM₁ and PM₂. The CBP of DM₂ was 5.77 times as much as PM₂. The relationship between CBP and four factors including volatile fatty acid (VFA), TAN, total alkalinity and pH was analyzed. pH gained the maximum determination coefficient with the CBP among all sets and total alkalinity showed negative correlation with CBP of PM₁ and DM₁. Copyright © 2014 Elsevier Ltd. All rights reserved.

Supersaturation of Dissolved Hydrogen and Methane in Rumen of Tibetan Sheep

PubMed Central

Wang, Min; Ungerfeld, Emilio M.; Wang, Rong; Zhou, Chuan She; Basang, Zhu Zha; Ao, Si Man; Tan, Zhi Liang

2016-01-01

Hydrogen (H2) is an essential substrate for methanogens to produce methane (CH4), and also influences pathways of volatile fatty acids (VFA) production in the rumen. Dissolved H2 (H2 (aq)) is the form of H2 available to microbes, and dissolved CH4 (CH4 (aq)) is important for indicating methanogens activity. Rumen H2 (aq) concentration has been estimated by assuming equilibrium with headspace gaseous H2 (H2 (g)) concentration using Henry's law, and has also been directly measured in the liquid phase in some in vitro and in vivo experiments. In this in vivo study, H2 (aq) and CH4 (aq) concentration measured directly in rumen fluid and their corresponding concentrations estimated from their gaseous phase concentrations, were compared to investigate the existence of equilibrium between the gas and liquid phases. Twenty-four Tibetan sheep were randomly assigned to two mixed diets containing the same concentrate mixed with oat grass (OG diet) or barley straw (BS diet). Rumen gaseous phase and contents were sampled using rumenocentesis and oral stomach tubing, respectively. Rumen H2 (aq) and CH4 (aq) concentration and VFA profile differed between sheep fed OG and BS diets. Measured H2 (aq) and CH4 (aq) concentration were greater than H2 (aq) and CH4 (aq) concentrations estimated using gas concentrations, indicating lack of equilibrium between gas and liquid phase and supersaturation of H2 and CH4 in rumen fluid. As a consequence, Gibbs energy changes (ΔG) estimated for various metabolic pathways were different when calculated using dissolved gases concentrations directly measured and when using dissolved gases concentrations assuming equilibrium with the gaseous phase. Dissolved CH4, but not CH4 (g), was positively correlated with H2 (aq). Both H2 (aq) and H2 (g) concentrations were positively correlated with the molar percentage of butyrate and negatively correlated with the molar percentage of acetate. In summary, rumen fluid was supersaturated with both H2 and CH4, and H2 (aq) was closely associated with the VFA profile and CH4 (aq) concentration. The assumption of equilibrium between dissolved gases and gaseous phase affected ΔG estimation. PMID:27379028

Stay-green ranking and maturity of corn hybrids: 2. Effects on the performance of lactating dairy cows.

PubMed

Arriola, K G; Kim, S C; Staples, C R; Adesogan, A T

2012-02-01

To address producer concerns that feeding high stay-green (SG) corn hybrids is associated with decreased performance and health problems in dairy cows, this study examined how the performance of cows was affected by feeding hybrids with contrasting SG rankings and maturities. Two near-isogenic corn hybrids with high (HSG; Croplan Genetics 691, Croplan Genetics, St. Paul, MN) and low (LSG; Croplan Genetics 737) SG rankings were grown on separate halves of a 10-ha field, harvested at 27% (maturity 1) or 35% (maturity 2) dry matter (DM) and ensiled in bag silos for 84 and 77 d, respectively. A further treatment involved addition of water (15 L/t) to the HSG maturity 1 hybrid during packing to compound the potential negative effects of excess water in the HSG hybrid. Each of the resulting silages was included in a total mixed ration consisting of 35, 55, and 10% (DM basis) of corn silage, concentrate, and alfalfa hay, respectively. In experiment 1, the total mixed ration was fed for ad libitum consumption twice daily to 30 Holstein cows (92±18 d in milk). This experiment had a completely randomized design and consisted of two 28-d periods, each with 14 d for adaptation and 14 d for sample collection. In experiment 2, the ruminal fermentation of the diets was measured using 5 ruminally cannulated cows on the last day of three 15-d periods. Ruminal contraction rate (2.28±0.14 contractions/min), milk yield (36.7±1.3 kg/d), yield of milk protein (1.1±0.03 kg/d), and concentration of milk protein (2.9±0.03%) were not affected by treatment. Feeding diets containing HSG instead of LSG reduced intake of crude protein (CP) and neutral detergent fiber, digestibility of neutral detergent fiber, and concentrations of ruminal total volatile fatty acids (VFA) and milk fat when the hybrids were harvested at 27% DM but not 35% DM. Across maturity stages, feeding diets containing HSG instead of LSG decreased DM and CP digestibility, increased rectal temperature and plasma ceruloplasmin concentration, and increased the efficiency of milk production. Except for increasing yeast and mold counts, adding water to the HSG hybrid harvested at 27% DM did not have adverse effects but was associated with greater starch intake, CP digestibility, and ruminal total VFA concentration, and decreased acetate to propionate ratio in dairy cows. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

In vitro fermentation of total mixed diets differing in concentrate proportion: relative effects of inocula and substrates.

PubMed

Serment, Amélie; Giger-Reverdin, Sylvie; Schmidely, Philippe; Dhumez, Ophélie; Broudiscou, Laurent P; Sauvant, Daniel

2016-01-15

In vitro techniques are used to predict ruminant feedstuff values or characterise rumen fermentation. As the results are influenced by several factors, such as the relative effects of inocula and substrates, this study aimed to examine in vitro incubation of two total mixed rations (substrates) differing in their proportion of concentrate [low (L): 350 g kg(-1) vs. high (H): 700 g kg(-1)] incubated in inocula provided by goats fed either a L or a H diet. Gas production and composition in carbon dioxide (CO2), methane (CH4 ) and hydrogen (H2), volatile fatty acids (VFAs), soluble carbohydrates (SCs) and ammonia (NH3) concentrations, and pH of the fermentation fluid were measured. In comparison with the L inoculum and L substrate, the H ones produced more CO2 and CH4 gas, which led to higher SCs and VFA concentrations, and lower acetate-to-propionate ratio and NH3 concentration, with a predominant effect of the inoculum. The effects of the inocula and of the substrates were additive using donor animals adapted to the diets. © 2015 Society of Chemical Industry.

Quantification of volatile fatty acids from cattle manure via non-catalytic esterification for odour indication.

PubMed

Lee, Sang-Ryong; Lee, Jechan; Cho, Seong-Heon; Kim, Jieun; Oh, Jeong-Ik; Tsang, Daniel C W; Jeong, Kwang-Hwa; Kwon, Eilhann E

2018-01-01

This report proposes a new approach to evaluate the odour nuisance of cattle manure samples from three different cattle breeds (i.e., native cattle, beef cattle, and milk cow) by means of quantification and speciation of volatile fatty acids (VFAs). To this end, non-catalytic esterification thermally induced in the presence of a porous material (silica) was undertaken, and the optimal operational parameters such as the derivatizing temperature (330°C) for the maximum yield (≥99±0.4%) of volatile fatty acid methyl esters (VFAMEs) were established. Among the VFA species in cattle manure based on quantification of VFAs, the major species were acetic, butyric and valeric acid. Considering the odour threshold of each VFA, our experimental results suggested that the major contributors to odour nuisance were C 4-5 VFA species (i.e., butyric and valeric acid). Hydrothermal treatment was performed at 150°C for 0-40min to correlate the formation of VFAs with different types of cattle feed formulations. Our experimental data demonstrated that the formation of total VFAs is linearly proportional to the hydrothermal treatment duration and the total content of VFAs in native cattle, beef cattle, and milk cow manure samples reached up to ~1000, ~3200, and ~2800ppm, respectively. Thus, this study demonstrated that the degree of VFA formation is highly dependent on cattle feed formulations, which rely significantly on the protein content. Furthermore, the hydrothermal treatment provides a favourable condition for generating more VFAs. In this context, producing cattle manure into refused derived fuel (RDF) via a hydrothermal treatment is not a viable option to control odour. Copyright © 2017 Elsevier B.V. All rights reserved.

Improved volatile fatty acid and biomethane production from lipid removed microalgal residue (LRμAR) through pretreatment.

PubMed

Suresh, Arumuganainar; Seo, Charles; Chang, Ho Nam; Kim, Yeu-Chun

2013-12-01

Renewable energy from lipid removed microalgal residues (LRμARs) serves as a promising tool for sustainable development of the microalgal biodiesel industry. Hence, in this study, LRμAR from Ettlia sp. was characterized for its physico-biochemical parameters, and applied to various pretreatment to increase the biodegradability and used in batch experiments for the production of volatile fatty acids (VFA) and biomethane. After various pretreatments, the soluble organic matters were increased at a maximum of 82% in total organic matters in alkali-autoclaved sample. In addition, VFA and methane production was enhanced by 30% and 40% in alkali-sonicated and alkali-autoclaved samples, respectively. Methane heating value was recovered at maximum of 6.6 MJ kg(-1)VS in alkali-autoclaved conditions with comparison to non-pretreated samples. The pretreatment remarkably improved LRμAR solubilization and enhanced VFA and biomethane production, which holds immense potential to eventually reduce the cost of algal biodiesel. Copyright © 2013 Elsevier Ltd. All rights reserved.

Acidogenic fermentation characteristics of different types of protein-rich substrates in food waste to produce volatile fatty acids.

PubMed

Shen, Dongsheng; Yin, Jun; Yu, Xiaoqin; Wang, Meizhen; Long, Yuyang; Shentu, Jiali; Chen, Ting

2017-03-01

In this study, tofu and egg white, representing typical protein-rich substrates in food waste based on vegetable and animal protein, respectively, were investigated for producing volatile fatty acids (VFAs) by acidogenic fermentation. VFA production, composition, conversion pathways and microbial communities in acidogenesis from tofu and egg white with and without hydrothermal (HT) pretreatment were compared. The results showed HT pretreatment could improve the VFA production of tofu but not for egg white. The optimum VFA yields were 0.46g/gVS (tofu with HT) and 0.26g/gVS (egg white without HT), respectively. Tofu could directly produce VFAs through the Stickland reaction, while egg white was converted to lactate and VFAs simultaneously. About 30-40% of total protein remained in all groups after fermentation. Up to 50% of the unconverted soluble protein in the HT groups was protease. More lactate-producing bacteria, mainly Leuconostoc and Lactobacillus, were present during egg white fermentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation into the effect of high concentrations of volatile fatty acids in anaerobic digestion on methanogenic communities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Franke-Whittle, Ingrid H., E-mail: ingrid.whittle@uibk.ac.at; Walter, Andreas; Ebner, Christian

Highlights: • Different methanogenic communities in mesophilic and thermophilic reactors. • High VFA levels do not cause major changes in archaeal communities. • Real-time PCR indicated greater diversity than ANAEROCHIP microarray. - Abstract: A study was conducted to determine whether differences in the levels of volatile fatty acids (VFAs) in anaerobic digester plants could result in variations in the indigenous methanogenic communities. Two digesters (one operated under mesophilic conditions, the other under thermophilic conditions) were monitored, and sampled at points where VFA levels were high, as well as when VFA levels were low. Physical and chemical parameters were measured, andmore » the methanogenic diversity was screened using the phylogenetic microarray ANAEROCHIP. In addition, real-time PCR was used to quantify the presence of the different methanogenic genera in the sludge samples. Array results indicated that the archaeal communities in the different reactors were stable, and that changes in the VFA levels of the anaerobic digesters did not greatly alter the dominating methanogenic organisms. In contrast, the two digesters were found to harbour different dominating methanogenic communities, which appeared to remain stable over time. Real-time PCR results were inline with those of microarray analysis indicating only minimal changes in methanogen numbers during periods of high VFAs, however, revealed a greater diversity in methanogens than found with the array.« less

Investigation of the impact of trace elements on anaerobic volatile fatty acid degradation using a fractional factorial experimental design.

PubMed

Jiang, Ying; Zhang, Yue; Banks, Charles; Heaven, Sonia; Longhurst, Philip

2017-11-15

The requirement of trace elements (TE) in anaerobic digestion process is widely documented. However, little is understood regarding the specific requirement of elements and their critical concentrations under different operating conditions such as substrate characterisation and temperature. In this study, a flask batch trial using fractional factorial design is conducted to investigate volatile fatty acids (VFA) anaerobic degradation rate under the influence of the individual and combined effect of six TEs (Co, Ni, Mo, Se, Fe and W). The experiment inoculated with food waste digestate, spiked with sodium acetate and sodium propionate both to 10 g/l. This is followed by the addition of a selection of the six elements in accordance with a 2 6-2 fractional factorial principle. The experiment is conducted in duplicate and the degradation of VFA is regularly monitored. Factorial effect analysis on the experimental results reveals that within these experimental conditions, Se has a key role in promoting the degradation rates of both acetic and propionic acids; Mo and Co are found to have a modest effect on increasing propionic acid degradation rate. It is also revealed that Ni shows some inhibitory effects on VFA degradation, possibly due to its toxicity. Additionally, regression coefficients for the main and second order effects are calculated to establish regression models for VFA degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stimulation of the anaerobic digestion of the dry organic fraction of municipal solid waste (OFMSW) with carbon-based conductive materials.

PubMed

Dang, Yan; Sun, Dezhi; Woodard, Trevor L; Wang, Li-Ying; Nevin, Kelly P; Holmes, Dawn E

2017-08-01

Growth of bacterial and archaeal species capable of interspecies electron exchange was stimulated by addition of conductive materials (carbon cloth or granular activated carbon (GAC)) to anaerobic digesters treating dog food (a substitute for the dry-organic fraction of municipal solid waste (OFMSW)). Methane production (772-1428mmol vs <80mmol), volatile solids removal (78%-81% vs 54%-64%) and COD removal efficiencies (∼80% vs 20%-30%) were all significantly higher in reactors amended with GAC or carbon cloth than controls. OFMSW degradation was also significantly accelerated and VFA concentrations were substantially lower in reactors amended with conductive materials. These results suggest that both conductive materials (carbon cloth and GAC) can promote conversion of OFMSW to methane even in the presence of extremely high VFA concentrations (∼500mM). Copyright © 2017 Elsevier Ltd. All rights reserved.

Prognostic Impact of Visceral Fat Amount and Branched-Chain Amino Acids (BCAA) in Hepatocellular Carcinoma.

PubMed

Higashi, Takaaki; Hayashi, Hiromitsu; Kaida, Takayoshi; Arima, Kota; Takeyama, Hideaki; Taki, Katsunobu; Izumi, Daisuke; Tokunaga, Ryuma; Kosumi, Keisuke; Nakagawa, Shigeki; Okabe, Hirohisa; Imai, Katsunobu; Nitta, Hidetoshi; Hashimoto, Daisuke; Chikamoto, Akira; Beppu, Toru; Baba, Hideo

2015-12-01

Dysregulation of lipid and amino acid metabolism in patients with liver diseases results in obesity-related carcinogenesis and decreased levels of branched-chain amino acids (BCAA), respectively. This study assessed the clinical and prognostic impact of visceral fat amount (VFA) and its association with amino acid metabolism in patients with hepatocellular carcinoma (HCC). In this study, 215 patients who underwent hepatic resection for HCC were divided into two groups based on VFA criteria for metabolic abnormalities in Japan. Computed tomography was used to measure VFA at the third lumbar vertebra in the inferior direction. Of the 215 patients, 132 had high and 83 had low VFA. High VFA was significantly associated with older age and higher body mass index (BMI), subcutaneous fat amount, and BCAA, but not with liver function, nutrient status, or tumoral factors. VFA was positively correlated with BMI (P < 0.0001; r = 0.63) and BCAA levels (P < 0.0001; r = 0.29). Overall survival was significantly greater in the high than in the low VFA group (P = 0.002). Multivariate analyses showed that high VFA [hazard ratio (HR) 7.06; P = 0.024] and neutrophil/lymphocyte ratio (HR 3.47; P = 0.049) were significantly prognostic of overall survival, whereas subcutaneous fat amount, BMI, BCAA, serum albumin, and prognostic nutritional index were not. High VFA was associated with a high BCAA level, with high VFA prognostic of improved overall survival in Japanese patients with HCC.

Mitigating ammonia inhibition of thermophilic anaerobic treatment of digested piggery wastewater: use of pH reduction, zeolite, biomass and humic acid.

PubMed

Ho, L; Ho, G

2012-09-15

High free ammonia released during anaerobic digestion of livestock wastes is widely known to inhibit methanogenic microorganisms and result in low methane production. This was encountered during our earlier thermophilic semi-continuously fed continuously-stirred tank reactor (CSTR) treatment of piggery wastewater. This study explored chemical and biological means to mitigate ammonia inhibition on thermophilic anaerobic treatment of piggery wastewater with the aim to increase organic volatile carbon reduction and methane production. A series of thermophilic anaerobic batch experiments were conducted on the digested piggery effluent to investigate the effects of pH reduction (pH 8.3 to 7.5, 7.0 and 6.5) and additions of biomass (10% v/v and 19% v/v anaerobic digested piggery biomass and aerobic-anaerobic digested municipal biomass), natural zeolite (10, 15 and 20 g/L) and humic acid (1, 5 and 10 g/L) on methane production at 55 °C for 9-11 days. Reduction of the wastewater pH from its initial pH of 8.3 to 6.5 produced the greatest stimulation of methane production (3.4 fold) coupled with reductions in free ammonia (38 fold) and total volatile fatty acids (58% TVFA), particularly acetate and propionate. Addition of 10-20 g/L zeolite to piggery wastewater with and without pH reduction to 6.5 further enhanced total VFA reduction and methane production over their respective controls, with 20 g/L zeolite producing the highest enhancement effect despite the ammonia-nitrogen concentrations of the treated wastewaters remaining high. Without pH reduction, zeolite concentration up to 20 g/L was required to achieve comparable methane enhancement as the pH-reduced wastewater at pH 6.5. Although biomass (10% v/v piggery and municipal wastes) and low humic acid (1 and 5 g/L) additions enhanced total VFA reduction and methane production, they elevated the residual effluent total COD concentrations over the control wastewaters (pH-unadjusted and pH-reduced) unlike zeolite treatment. The outcomes from these batch experiments support the use of pH reduction to 6.5 and zeolite treatment (10-20 g/L) as effective strategies to mitigate ammonia inhibition of the thermophilic anaerobic treatment of piggery wastewater. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of sugar fatty acid esters on rumen fermentation in vitro.

PubMed

Wakita, M; Hoshino, S

1987-11-01

1. The effect of sugar fatty acid esters (SFEs; currently used as food additives for human consumption) on rumen volatile fatty acids (VFA) and gas production was studied with sheep rumen contents in vitro. 2. Some SFEs having monoester contents of more than 70% increased the molar proportion of propionate in conjunction with reduction in the acetate:propionate ratio when the individual SFE was added to rumen contents in a final concentration of 4 g/l. Laurate sugar ester was the most potent propionate enhancer and rumen gas depressor, the effective dose being as low as 1 g/l in a final concentration. Fatty acid esters other than SFEs had little, if any, effect on rumen VFA production and their molar proportions. 3. Approximately 50% of laurate sugar ester was hydrolysed by in vitro incubation with rumen fluid for 2 h. The addition of fatty acids and sucrose was also effective in the alterations of rumen VFA and gas production. However, the effect of SFEs on in vitro rumen fermentation was significantly greater than that of their constituent fatty acids or sucrose, or both. Accordingly, the effect appeared to be ascribed to the complex action of SFE itself and to its constituents, free fatty acids and sucrose. 4. SFEs, at the level of 4 g/l, reduced substantially the froth formation (ingesta volume increase) and seemed to be effective for the prevention of bloat.

Comparison of long-term voice outcomes after vocal fold augmentation using autologous fat injection by direct microlaryngoscopy versus office-based calcium hydroxylapatite injection.

PubMed

Zeleník, Karol; Walderová, Radana; Kučová, Hana; Jančatová, Debora; Komínek, Pavel

2017-08-01

The objective is to compare the long-term voice outcomes of vocal fold augmentation (VFA) using autologous fat injection via direct microlaryngoscopy versus office-based calcium hydroxylapatite (CaHA) injection. Patients with glottal insufficiency and a gap no greater than 3 mm caused by unilateral vocal fold paralysis or vocal fold atrophy were prospectively recruited to the study from September 2012 to September 2015. From September 2012 to May 2014, VFA was only performed using autologous fat via direct microlaryngoscopy under general anesthesia (N = 14). From May 2014 to September 2015, VFA was performed as an office-based procedure using a transoral approach to inject CaHA (N = 17). Videolaryngostroboscopic evaluation, subjective satisfaction with voice, voice handicap index (VHI), and maximal phonation time (MPT) were analyzed pre-injection and 12 months after VFA. A total of 31 patients were analyzed. One year after VFA, 67.8% of the patients were satisfied with their voice, with no significant difference between groups (P = 0.247). The mean improvement in VHI in the autologous fat group was 31.6 ± 16.82 versus 35 ± 27.24 in the CaHA group (P = 0.664). MPT improvement was also similar in the two groups: 5.5 ± 2.52 for the autologous fat group versus 6.0 ± 3.98 for the CaHA group (P = 0.823). Both autologous fat injection via direct microlaryngoscopy and office-based CaHA injection have good long-term results. There were no differences in the treatment results of the two procedures 1 year after injection.

Visceral adiposity and skeletal muscle mass are independently and synergistically associated with left ventricular structure and function: the Korean Genome and Epidemiology Study.

PubMed

Park, Juri; Kim, Nan Hee; Kim, Seong Hwan; Kim, Jin-Seok; Kim, Yong Hyun; Lim, Hong Euy; Kim, Eung Ju; Na, Jin Oh; Cho, Goo-Yeong; Baik, Inkyung; Kim, Doo Man; Choi, Dong Seop; Lee, Seung Ku; Shin, Chol

2014-10-20

Obesity and low muscle mass may coexist as age-related changes in body composition. We aimed to investigate the effect of visceral adiposity and skeletal muscle mass on left ventricular (LV) structure and function in the general population. A total of 1941 participants without known cardiovascular disease were enrolled from the Korean Genome and Epidemiology Study. Visceral fat area (VFA) was assessed by computed tomography. Appendicular skeletal muscle mass (ASM) was estimated by dual-energy X-ray absorptiometry and was used as a percentage of body weight (ASM/Wt). LV structure and function were assessed by tissue Doppler imaging (TDI) echocardiography. Across VFA tertiles, ASM increased, but ASM/Wt decreased (all P<0.001). In multivariate models adjusted for conventional cardiovascular risk factors, LV mass index and LV diastolic parameters, such as left atrial dimension, TDI Ea velocity, and E/Ea ratio, were significantly impaired as VFA increased. On the other hand, an increase in ASM/Wt was associated with a decrease in LV mass index and improvement of LV diastolic parameters. With regard to LV mass index and TDI Ea velocity, VFA and ASM/Wt showed synergistic effects (all P interaction<0.05). When both VFA and ASM/Wt were simultaneously included in the same model, both remained independent predictors of LV mass index and TDI Ea velocity. More visceral fat and less muscle mass are independently and synergistically associated with an increase in LV mass index and impairment of LV diastolic parameters. Further research is needed to explore the complex mechanisms underlying these associations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Vfa1 binds to the N-terminal microtubule-interacting and trafficking (MIT) domain of Vps4 and stimulates its ATPase activity.

PubMed

Vild, Cody J; Xu, Zhaohui

2014-04-11

The endosomal sorting complexes required for transport (ESCRT) are responsible for multivesicular body biogenesis, membrane abscission during cytokinesis, and retroviral budding. They function as transiently assembled molecular complexes on the membrane, and their disassembly requires the action of the AAA-ATPase Vps4. Vps4 is regulated by a multitude of ESCRT and ESCRT-related proteins. Binding of these proteins to Vps4 is often mediated via the microtubule-interacting and trafficking (MIT) domain of Vps4. Recently, a new Vps4-binding protein Vfa1 was identified in a yeast genetic screen, where overexpression of Vfa1 caused defects in vacuolar morphology. However, the function of Vfa1 and its role in vacuolar biology were largely unknown. Here, we provide the first detailed biochemical and biophysical study of Vps4-Vfa1 interaction. The MIT domain of Vps4 binds to the C-terminal 17 residues of Vfa1. This interaction is of high affinity and greatly stimulates the ATPase activity of Vps4. The crystal structure of the Vps4-Vfa1 complex shows that Vfa1 adopts a canonical MIT-interacting motif 2 structure that has been observed previously in other Vps4-ESCRT interactions. These findings suggest that Vfa1 is a novel positive regulator of Vps4 function.

Vfa1 Binds to the N-terminal Microtubule-interacting and Trafficking (MIT) Domain of Vps4 and Stimulates Its ATPase Activity*

PubMed Central

Vild, Cody J.; Xu, Zhaohui

2014-01-01

The endosomal sorting complexes required for transport (ESCRT) are responsible for multivesicular body biogenesis, membrane abscission during cytokinesis, and retroviral budding. They function as transiently assembled molecular complexes on the membrane, and their disassembly requires the action of the AAA-ATPase Vps4. Vps4 is regulated by a multitude of ESCRT and ESCRT-related proteins. Binding of these proteins to Vps4 is often mediated via the microtubule-interacting and trafficking (MIT) domain of Vps4. Recently, a new Vps4-binding protein Vfa1 was identified in a yeast genetic screen, where overexpression of Vfa1 caused defects in vacuolar morphology. However, the function of Vfa1 and its role in vacuolar biology were largely unknown. Here, we provide the first detailed biochemical and biophysical study of Vps4-Vfa1 interaction. The MIT domain of Vps4 binds to the C-terminal 17 residues of Vfa1. This interaction is of high affinity and greatly stimulates the ATPase activity of Vps4. The crystal structure of the Vps4-Vfa1 complex shows that Vfa1 adopts a canonical MIT-interacting motif 2 structure that has been observed previously in other Vps4-ESCRT interactions. These findings suggest that Vfa1 is a novel positive regulator of Vps4 function. PMID:24567329

Individual animal variability in ruminal bacterial communities and ruminal acidosis in primiparous Holstein cows during the periparturient period.

PubMed

Mohammed, R; Stevenson, D M; Weimer, P J; Penner, G B; Beauchemin, K A

2012-11-01

The purpose of this study was to investigate variability among individual cows in their severity of ruminal acidosis (RA) pre- and postpartum, and determine whether this variability was related to differences in their ruminal bacterial community composition (BCC). Variability in the severity of RA among individual cows was characterized based on ruminal fermentation variables. Effects of prepartum dietary treatment on the severity of RA were also examined. Fourteen Holstein heifers paired by expected calving date and BCS were allotted to 1 of 2 prepartum dietary treatments: low-concentrate or high-concentrate diets. All cows received the same lactation diet postpartum. Microbial DNA extracted from 58 ruminal digesta samples in total collected prepartum (d -50, -31, and -14; 27 samples) and postpartum (d +14 and +52; 31 samples) and amplified by PCR were subjected to automated ribosomal intergenic spacer analysis. Changes in ruminal variables over time [pH, volatile fatty acids (VFA), and acidosis indicators, including duration and area under the rumen pH curve below 5.8, 5.5, and 5.2, measured on d -54, -35, -14, -3, +3, +17, +37, and +58] were analyzed using principal components analysis. Based on the shift (defined as the distance of the mean loadings) between the prepartum and postpartum period for each cow, the 14 cows were classified into 3 groups: least acidotic (n=5), most acidotic (n=5), and intermediate (n=4). Cows in the most acidotic group had greater severity of RA (measured as duration of total RA, mild RA, moderate RA, and acute RA; area under the pH curve for total RA, mild RA, and moderate RA) postpartum than prepartum, and this difference between periods was greater than for the least acidotic cows. Similarly, the RA index (total area of pH <5.8 normalized to intake) showed an interaction between severity of RA and period. The variation in the severity of RA was independent of intake, total VFA concentration, and individual VFA proportions. Production variables (milk yield, fat percentage, fat yield, fat-corrected milk, and efficiency of milk production) were not influenced by the severity of RA. Ruminal BCC was not influenced by dietary treatment or period. However, some cows experienced greater shift in BCC than other cows across the periods. Based on the magnitude of the shift in BCC (distance between mean ordination values across the periods for each cow), cows were grouped into 3 BCC profile categories: stable (5 cows with lesser shift), unstable (5 cows with greater shift), and intermediate (4 cows with average shift). Cows demonstrating a greater shift in BCC were not necessarily those in the most acidotic group and vice versa. The shift in ruminal fermentation variables (principal components analysis rankings) and the shift in BCC (automated ribosomal intergenic spacer analysis rankings) between pre- and postpartum were not related (n=14; R(2)=0.00). It was concluded that not all cows are equally susceptible to RA and postpartum shifts in BCC appear to be independent of the differences in the severity of RA postpartum. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Early modulation of the cecal microbial activity in the young rabbit with rapidly fermentable fiber: impact on health and growth.

PubMed

Jacquier, V; Combes, S; Oswald, I P; Rogel-Gaillard, C; Gidenne, T

2014-12-01

This study aimed at comparing various diets predicted to induce different stimulations of the cecal microbial activity of the young rabbit fed ad libitum from 16 to 70 d of age: i) a diet enriched with rapidly fermentable fiber expected to stimulate the cecal microbial activity (RFF group); ii) a control diet with a standard composition (C group); iii) and the same control diet with tiamulin and apramycin antibiotics, expected to inhibit the microbial activity (C+AB group). A total of 398 rabbits were used from 42 litters and weaned at 28 d of age. An in vivo digestibility trial was performed on 36 rabbits of 42 to 46 d of age housed in individual metabolic cages. The feed intake and growth rates were lower in the RFF group compared with the C+AB group (-15% in ADFI and -11% in ADG, P<0.001), with a lower weight of -183 g at 70 d (P<0.001). No significant difference was found on ADG and final BW between the RFF and the C groups, but the RFF diet allowed a better G:F ratio at postweaning (P<0.01). The digestion of soluble fiber (total dietary fiber minus NDF) was greater for the RFF group. The C+AB diet had a positive effect on the postweaning morbidity rate (P<0.05) but did not affect the mortality rate and the health risk index (morbidity and mortality). Conversely, the RFF diet appeared to reduce the mortality rate compared with the C+AB diet, especially before 41 d of age. Concerning the cecal microbial activity, a supply of RFF in the diet increased the cecal VFA concentrations (+28% vs. C+AB and +22% vs. C, P<0.001) and lowered the pH. The VFA pattern was affected at 45 and 60 d, with a dominance of acetate in the RFF group (+4% vs. C+AB and C groups, P<0.001) instead of butyrate in the C+AB and C groups (-3.6% and -5% vs. C+AB and C, respectively, P<0.001). Antibiotics addition (C+AB group) reduced the VFA concentration, but only after weaning (-25% at 45 d of age) without changing the fermentation pattern. In conclusion, early intake of RFF in young rabbits stimulated the cecal microbial activity, and reduced the voluntary feed intake, leading to a reduced G:F ratio.

Use of Acetate, Propionate, and Butyrate for Reduction of Nitrate and Sulfate and Methanogenesis in Microcosms and Bioreactors Simulating an Oil Reservoir

PubMed Central

Shen, Yin; An, Dongshan; Voordouw, Gerrit

2017-01-01

ABSTRACT Acetate, propionate, and butyrate (volatile fatty acids [VFA]) occur in oil field waters and are frequently used for microbial growth of oil field consortia. We determined the kinetics of use of these VFA components (3 mM each) by an anaerobic oil field consortium in microcosms containing 2 mM sulfate and 0, 4, 6, 8, or 13 mM nitrate. Nitrate was reduced first, with a preference for acetate and propionate. Sulfate reduction then proceeded with propionate (but not butyrate) as the electron donor, whereas the fermentation of butyrate (but not propionate) was associated with methanogenesis. Microbial community analyses indicated that Paracoccus and Thauera (Paracoccus-Thauera), Desulfobulbus, and Syntrophomonas-Methanobacterium were the dominant taxa whose members catalyzed these three processes. Most-probable-number assays showed the presence of up to 107/ml of propionate-oxidizing sulfate-reducing bacteria (SRB) in waters from the Medicine Hat Glauconitic C field. Bioreactors with the same concentrations of sulfate and VFA responded similarly to increasing concentrations of injected nitrate as observed in the microcosms: sulfide formation was prevented by adding approximately 80% of the nitrate dose needed to completely oxidize VFA to CO2 in both. Thus, this work has demonstrated that simple time-dependent observations of the use of acetate, propionate, and butyrate for nitrate reduction, sulfate reduction, and methanogenesis in microcosms are a good proxy for these processes in bioreactors, monitoring of which is more complex. IMPORTANCE Oil field volatile fatty acids acetate, propionate, and butyrate were specifically used for nitrate reduction, sulfate reduction, and methanogenic fermentation. Time-dependent analyses of microcosms served as a good proxy for these processes in a bioreactor, mimicking a sulfide-producing (souring) oil reservoir: 80% of the nitrate dose required to oxidize volatile fatty acids to CO2 was needed to prevent souring in both. Our data also suggest that propionate is a good substrate to enumerate oil field SRB. PMID:28130297

Effect of acarbose on acute acidosis.

PubMed

McLaughlin, C L; Thompson, A; Greenwood, K; Sherington, J; Bruce, C

2009-06-01

A challenge model was used to evaluate a new approach to controlling acute acidosis. Acute acidosis reduces performance in both dairy and beef cattle and most often occurs as a consequence of ingestion of large amounts of readily fermentable starch, resulting in increased production of volatile fatty acids (VFA) and lactic acid and a reduction in ruminal pH. Acarbose is an alpha-amylase and glucosidase inhibitor that slows the rate of degradation of starch to glucose, thereby reducing the rate of VFA production and maintaining rumen pH at a more stable level. It is commercially available (Glucobay, Bayer, Wuppertal, Germany) and indicated for the control of blood glucose in diabetic patients. The ability of acarbose to reduce the incidence of acidosis and the comparative efficacies of acarbose, sodium bicarbonate, and monensin were tested in 3 acute acidosis challenge experiments in cattle. Rumen-cannulated Holstein steers were challenged with a mixture of 48.4% cornstarch, 48.4% ground corn, 2.1% sodium caseinate, and 1.1% urea with or without test substance. The challenge was administered at a rate of 12.5 g/kg of body weight (BW) as a slurry through the cannula directly into the rumen. Ruminal pH was monitored at 10-min intervals throughout the study. Animals were removed from study and rumen contents replaced if they exhibited acute acidosis as defined as pH <4.5. If acidosis was not observed within 24 h, animals were subjected to a second challenge. Ruminal fluid samples were taken for measurement of VFA and lactate concentrations at various intervals after the challenge. In experiment 1, the carbohydrate challenge induced acidosis in 4 of 4 control animals and 0 of 4 animals treated with 2.14 or 21.4 mg of acarbose/kg of BW in the challenge based on the criterion of pH <4.5. In experiment 2, the carbohydrate challenge induced acidosis in 4 of 7 control animals and 1 of 7 animals when 1.07 mg of acarbose/kg of BW was included in the challenge. In experiment 3, acidosis was induced in 7 of 7 animals in the control, 1% sodium bicarbonate, and 12 mg of monensin/kg of dry matter intake groups and in 3 of 8 steers administered 1.07 mg of acarbose/kg of BW in the challenge. Increases in lactate concentrations and decreases in total VFA associated with acute acidosis were mitigated by acarbose. Thus, acarbose, an amylase and glucosidase inhibitor, prevented or reduced the incidence of acidosis in an acute challenge model in steers and was more effective than monensin or sodium bicarbonate.

Anaerobic acidogenic digestion of olive mill wastewaters in biofilm reactors packed with ceramic filters or granular activated carbon.

PubMed

Bertin, Lorenzo; Lampis, Silvia; Todaro, Daniela; Scoma, Alberto; Vallini, Giovanni; Marchetti, Leonardo; Majone, Mauro; Fava, Fabio

2010-08-01

Four identically configured anaerobic packed bed biofilm reactors were developed and employed in the continuous acidogenic digestion of olive mill wastewaters to produce volatile fatty acids (VFAs), which can be exploited in the biotechnological production of polyhydroxyalkanoates. Ceramic porous cubes or granular activated carbon were used as biofilm supports. Aside packing material, the role of temperature and organic loading rate (OLR) on VFA production yield and mixture composition were also studied. The process was monitored through a chemical, microbiological and molecular biology integrated procedure. The highest wastewater acidification yield was achieved with the ceramic-based technology at 25 degrees C, with an inlet COD and an OLR of about 17 g/L and 13 g/L/day, respectively. Under these conditions, about the 66% of the influent COD (not including its VFA content) was converted into VFAs, whose final amount represented more than 82% of the influent COD. In particular, acetic, propionic and butyric acids were the main VFAs by composing the 55.7, 21.5 and 14.4%, respectively, of the whole VFA mixture. Importantly, the relative concentrations of acetate and propionate were affected by the OLR parameter. The nature of the packing material remarkable influenced the process performances, by greatly affecting the biofilm bacterial community structure. In particular, ceramic cubes favoured the immobilization of Firmicutes of the genera Bacillus, Paenibacillus and Clostridium, which were probably involved in the VFA producing process. (c) 2010 Elsevier Ltd. All rights reserved.

Effect of Solids Retention Time on the Denitrification Potential of Anaerobically Digested Swine Waste

NASA Astrophysics Data System (ADS)

Kinyua, Maureen Njoki

Three continuously stirred tank reactors (CSTR) were operated in semi continuous mode treating swine waste using anaerobic digestion. The reactors were used to test the effect of solid retention time (SRT) on CH4 yield, total ammonia nitrogen (TAN) concentrations, % volatile solids (VS), chemical oxygen demand (COD) and volatile fatty acids (VFA) removal, readily biodegradable COD concentration and the denitrification potential for the effluent in a biological nutrient removal (BNR) system. During Phase I of the study, the three reactors were operated at the same 28 day SRT for 16 weeks. SRTs were then changed during the 12 week Phase II period. The SRTs studied were 14, 21 and 28 days, with the same organic loading rate (OLR) of 1.88 ± 0.2 kg VS/ m3-day. The reactor with the lowest SRT (14 days) had the highest VS and VFA removal at 73.6 and 67.6% and lowest TAN concentration at 0.78 g NH4+-N/L, followed by the 21 day and 28 day reactors. This was likely due to the fast microbial growth rates and substrate utilization rates in this reactor compared with the other two. The 14 day reactor had the highest CH4 yield at 0.33 m3CH 4/kg VS added and readily biodegradable COD concentration at 0.93 COD/L. The variations in CH4 yield and readily biodegradable COD concentrations between the three reactors were not statistically significant. Denitrification potential for the reactors was 1.20, 0.73 and 0.56 g COD/g N for 14, 21 and 28 day reactors, respectively, and the differences were statistically significant. None of the reactors achieved a denitrification potential of 5 g COD/g N, the amount required to use effluent of anaerobically digested swine waste as an internal carbon source in a BNR. This was attributed to operating conditions such as freezing and thawing of the raw swine waste that maximized CH4 yield and lowered the readily biodegradable COD concentration. In addition the 14 day reactor had low TAN concentrations thus increasing the denitrification potential of the centrate from that reactor.

Effects of garlic oil, nitrate, saponin and their combinations supplemented to different substrates on in vitro fermentation, ruminal methanogenesis, and abundance and diversity of microbial populations.

PubMed

Patra, A K; Yu, Z

2015-07-01

To investigate the effect of garlic oil (G), nitrate (N), saponin (S) and their combinations supplemented to different forage to concentrate substrates on methanogenesis, fermentation, diversity and abundances of bacteria and Archaea in vitro. The study was conducted in an 8 × 2 factorial design with eight treatments and two substrates using mixed ruminal batch cultures obtained. Quillaja S (0·6 g l(-1) ), N (5 mmol l(-1) ) and G (0·27 g l(-1) ) were used separately or in binary and tertiary combinations. The two substrates contained grass hay and a dairy concentrate mixture at a 70 : 30 (high-forage substrate) ratio or a 30 : 70 (high-concentrate substrate) ratio. Ruminal fermentation and cellulolytic bacterial populations were affected by interaction between substrate and anti-methanogenic compounds. The inhibitor combinations decreased the methane production additively regardless of substrate. For the high-concentrate substrate, S decreased methane production to a greater extent, so did G and N individually for the high-forage substrate. Feed degradability and total volatile fatty acid (VFA) concentrations were not decreased by any of the treatments. Fibre degradability was actually improved by N+S for the high-forage substrate. VFA concentrations and profiles were affected differently by different anti-methanogenic inhibitors and their combinations. All treatments inhibited the growth of Archaea, but the effect on Fibrobacter succinogenes, Ruminococcus albus and Ruminococcus flavefaciens varied. The results suggest that substrate influences the efficacy of these inhibitors when they are used separately, but in combinations, they can lower methanogenesis additively without much influence from the substrate. The presented research provided evidence that binary and tertiary combination of garlic oil, nitrate and saponin can lower the methane production additively without adversely impacting rumen fermentation and degradability, and forage to concentrate ratio does not change the above effects. These anti-methanogenic inhibitors in combination may have practical application to mitigate methane emission from ruminants. © 2015 The Society for Applied Microbiology.

Effects of wheat dried distillers' grains with solubles and cinnamaldehyde on in vitro fermentation and protein degradation using the Rusitec technique.

PubMed

Lia, Yangling; He, Maolong; Li, Chun; Forster, Robert; Beauchemin, Karen Anne; Yang, Wenzhu

2012-04-01

This study was conducted to evaluate the effect of wheat dried distillers' grains with solubles (DDGS) and cinnamaldehyde (CIN) on in vitro fermentation and microbial profiles using the rumen simulation technique. The control substrate (10% barley silage, 85% barley grain and 5% supplement, on dry matter basis) and the wheat DDGS substrate (30% wheat DDGS replaced an equal portion of barley grain) were combined with 0 and 300 mg CIN/l of culture fluid. The inclusion of DDGS increased (p < 0.05) the concentration of volatile fatty acids (VFA) and the molar proportion of acetate and propionate. Dry matter disappearance (p = 0.03) and production of bacterial protein (p < 0.01) were greater, whereas the disappearances of crude protein (CP) and neutral detergent fibre were less (p < 0.01) for the DDGS than for the control substrate. With addition of CIN, concentration of total VFA decreased and fermentation pattern changed to greater acetate and less propionate proportions (p < 0.01). The CIN reduced (p < 0.01) methane production and CP degradability. The copy numbers of Fibrobacter, Prevotella and Archaea were not affected by DDGS but were reduced (p < 0.05) by CIN. The results indicate that replacing barley grain by DDGS increased nutrient fermentability and potentially increase protein flows to the intestine. Supplementation of high-grain substrates with CIN reduced methane production and potentially increased the true protein reaching the small intestine; however, overall reduction of feed fermentation may lower the feeding value of a high-grain diet.

Microbial conversion of synthetic and food waste-derived volatile fatty acids to lipids.

PubMed

Vajpeyi, Shashwat; Chandran, Kartik

2015-01-01

Lipid accumulation in the oleaginous yeast Cryptococcus albidus was evaluated using mixtures of volatile fatty acids (VFA) as substrates. In general, batch growth under nitrogen limitation led to higher lipid accumulation using synthetic VFA. During batch growth, an initial COD:N ratio of 25:1mg COD:mg N led to maximum intracellular lipid accumulation (28.3 ± 0.7% g/g dry cell weight), which is the maximum reported for C. albidus using VFA as the carbon source, without compromising growth kinetics. At this feed COD:N ratio, chemostat cultures fed with synthetic VFA yielded statistically similar intracellular lipid content as batch cultures (29.9 ± 1.9%, g/g). However, batch cultures fed with VFA produced from the fermentation of food waste, yielded a lower lipid content (14.9 ± 0.1%, g/g). The lipid composition obtained with synthetic and food-waste-derived VFA was similar to commercial biodiesel feedstock. We therefore demonstrate the feasibility of linking biochemical waste treatment and biofuel production using VFA as key intermediates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhancing sludge biodegradability and volatile fatty acid production by tetrakis hydroxymethyl phosphonium sulfate pretreatment.

PubMed

Wu, Qing-Lian; Guo, Wan-Qian; Bao, Xian; Yin, Ren-Li; Feng, Xiao-Chi; Zheng, He-Shan; Luo, Hai-Chao; Ren, Nan-Qi

2017-09-01

A new pretreatment method based on tetrakis hydroxymethyl phosphonium sulfate (THPS) biocide was tried to enhance sludge disintegration, and improved sludge biodegradability and subsequent volatile fatty acid (VFA) production. Sludge activity decreased to less than 10% after 2 days pretreatment using 20mg/g-TSS THPS, which also obviously destroyed EPS and cell membrane, and dissolved more biodegradable substances (48.8%) than raw sludge (19.7%). Moreover, 20mg/g-TSS THPS pretreatment shortened fermentation time to 4days and improved VFA production to 2778mg COD/L (4.35 times than that in control). Therein, the sum of n-butyric, n-valeric and iso-valeric acids unexpectedly accounted for 60.5% of total VFA (only 20.1% of that in control). The more high molecular weight VFAs (C4-C5) than low molecular VFAs (C2-C3) resulted from THPS pretreatment benefited to subsequent medium-chain volatile acids (C6-C12) generation to realize the separation and recovery of organic carbon more efficiently. Copyright © 2017. Published by Elsevier Ltd.

Effect of protein supplementation on ruminal parameters and microbial community fingerprint of Nellore steers fed tropical forages.

PubMed

Bento, C B P; Azevedo, A C; Gomes, D I; Batista, E D; Rufino, L M A; Detmann, E; Mantovani, H C

2016-01-01

In tropical regions, protein supplementation is a common practice in dairy and beef farming. However, the effect of highly degradable protein in ruminal fermentation and microbial community composition has not yet been investigated in a systematic manner. In this work, we aimed to investigate the impact of casein supplementation on volatile fatty acids (VFA) production, specific activity of deamination (SAD), ammonia concentration and bacterial and archaeal community composition. The experimental design was a 4×4 Latin square balanced for residual effects, with four animals (average initial weight of 280±10 kg) and four experimental periods, each with duration of 29 days. The diet comprised Tifton 85 (Cynodon sp.) hay with an average CP content of 9.8%, on a dry matter basis. Animals received basal forage (control) or infusions of pure casein (230 g) administered direct into the rumen, abomasum or divided (50 : 50 ratio) in the rumen/abomasum. There was no differences (P>0.05) in ruminal pH and microbial protein concentration between supplemented v. non-supplemented animals. However, in steers receiving ruminal infusion of casein the SAD and ruminal ammonia concentration increased 33% and 76%, respectively, compared with the control. The total concentration of VFA increased (P0.05) in species richness and diversity of γ-proteobacteria, firmicutes and archaea between non-supplemented Nellore steers and steers receiving casein supplementation in the rumen. However, species richness and the Shannon-Wiener index were lower (P<0.05) for the phylum bacteroidetes in steers supplemented with casein in the rumen compared with non-supplemented animals. Venn diagrams indicated that the number of unique bands varied considerably among individual animals and was usually higher in number for non-supplemented steers compared with supplemented animals. These results add new knowledge about the effects of ruminal and postruminal protein supplementation on metabolic activities of rumen microbes and the composition of bacterial and archaeal communities in the rumen of steers.

Ruminal fermentation and nutrient digestion in sheep fed hydroxyethylsoyamide.

PubMed

Jenkins, T C

1997-08-01

Hydroxyethylsoyamide (HESA) was reported previously to protect soybean oil from ruminal biohydrogenation and increase plasma unsaturated fatty acids in sheep. Two digestibility trials with sheep and a rumen in vitro trials were conducted in this study to determine the effects of HESA on ruminal VFA and nutrient digestibility. Trial 1 was a 4 x 4 Latin square with 17-d periods in which four wethers were fed either a control diet (CON) with no added fat, 2.5% soybean oil (SBO), 5% butylsoyamide (BuSA), or 5% HESA. The HESA diet was ground with a mortar and pestle before feeding to disperse fat lumps that formed during diet mixing. Compared with the CON diet, the HESA diet reduced DMI, acetate/ propionate (A/P), and total tract fiber digestibility, but these were not affected by SBO or BuSA. Trial 2 was a 24-h rumen in vitro study showing that total VFA concentration and A/P in cultures were reduced by 10% linoleic acid but not by 10% ethanolamine or 10% HESA. In Trial 3, four wethers were fed the CON and HESA diets in a replicated 2 x 2 Latin square to determine digestibility responses to HESA when grinding was avoided. Fiber digestibilities and A/P were not affected by HESA in Trial 3. The HESA in this study had variable effects on fiber digestibility that may have been related to physical attributes of the diet, including particle size. Substitution of ethanolamine for butylamine during synthesis of the amide increased fatty acid digestibility but reduced dry matter intake.

Effects of dietary protein levels and 2-methylbutyrate on ruminal fermentation, nutrient degradability, bacterial populations and urinary purine derivatives in Simmental steers.

PubMed

Wang, C; Liu, Q; Guo, G; Huo, W J; Pei, C X; Zhang, S L; Yang, W Z

2018-06-01

The objective of this study was to evaluate the effects of dietary crude protein (CP) levels and 2-methylbutyrate (MB) supplementation on ruminal fermentation, bacterial populations, microbial enzyme activity and urinary excretion of purine derivatives (PD) in Simmental steers. Eight ruminally cannulated Simmental steers, averaging 18 months of age and 465 ± 8.6 kg of body weight (BW), were used in a replicated 4 × 4 Latin square design by a 2 × 2 factorial arrangement. Low protein (98.5 g CP/kg dry matter [LP] or high protein (128.7 g CP/kg dry matter [HP]) diets were fed with MB supplementation (0 g [MB-] or 16.8 g steer -1  day -1 [MB+]). Steers were fed a total mixed ration with dietary corn straw to concentrate ratio of 50:50 (dry matter [DM] basis). The CP × MB interaction was observed for ruminal total VFA, molar proportions of acetate and propionate, acetate to propionate ratio, ammonia-N, effective degradability of neutral detergent fibre (NDF) and CP, microbial enzyme activity, bacterial populations and total PD excretion (p < .05). Ruminal pH decreased (p < .05), but ruminal total VFA concentration increased (p < .05) with increasing dietary CP level or MB supplementation. Acetate molar proportion increased (p = .043) with MB supplementation, but was not affected by dietary CP level. Propionate molar proportion decreased (p < .05) with increasing dietary CP level or MB supplementation. Consequently, acetate-to-propionate ratio increased (p = .001) with MB supplementation, but was not affected by dietary CP level. Ruminal ammonia-N content increased (p = .034) with increasing dietary CP level, but decreased (p = .012) with MB supplementation. The effective degradability of NDF and CP increased (p < .05) with increasing dietary CP level or MB supplementation. Microbial enzyme activity, bacterial populations and total PD excretion also increased (p < .05) with increasing dietary CP level or MB supplementation. The results indicated that ruminal fermentation, nutrient degradability, microbial enzyme activity, ruminal bacterial populations and microbial protein synthesis improved with increasing dietary CP level or MB supplementation in steers. © 2017 Blackwell Verlag GmbH.

Prevalence and consequence of subacute ruminal acidosis in Polish dairy herds.

PubMed

Stefańska, B; Nowak, W; Komisarek, J; Taciak, M; Barszcz, M; Skomiał, J

2017-08-01

The aim of this study was to estimate the prevalence of subacute ruminal acidosis (SARA) in Polish high-yielding dairy herds. Also, the relationships between the chemical composition of the diet and the feed particle size, ruminal pH and the occurrence of this metabolic disease and the fermentation profile were determined. Rumen fluid samples were obtained from a total of 213 cows from nine dairy herds (≥20 cows per herd) via rumenocentesis. Almost 14% (30/213) of cows as acidotic (pH<5.6) were found, which is indicative of SARA. Moreover, 44% of the herds were classified as SARA-positive and 56% as SARA-negative. Results of the current study suggested that the physically effective NDF (NDF >1.18 mm) -to-starch ratio could be better indices than peNDF >1.18 mm to preventing the occurrence of SARA, and their level should not be lower than 1.00. Also, linear negative relationships between rumen fluid pH and concentration of propionate, valerate and total VFA were determined. According to the herd's SARA status and rumen fluid biochemical indices, there were significant differences between the pH of rumen fluid (p ≤ 0.01), concentrations of acetate (p ≤ 0.05), propionate (p ≤ 0.05), n-butyrate (p ≤ 0.01), n-valerate (p ≤ 0.01), the sum of VFA (p ≤ 0.01) and ammonia (p ≤ 0.05) in SARA-positive herds compared to SARA-negative herds. The better understanding the strategy of ruminant nutrition to coordinate energy conversion and the role of the ruminal pH in regulating N-NH 3 production, absorption through rumen mucosa, urea secretion, the more successfully we can utilize these processes with due recognition of animal needs and welfare, as well as prevention of SARA occurrence. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Increased Incidence of Visual Field Abnormalities as Determined by Frequency Doubling Technology Perimetry in High Computer Users Among Japanese Workers: A Retrospective Cohort Study.

PubMed

Nakano, Tadashi; Hayashi, Takeshi; Nakagawa, Toru; Honda, Toru; Owada, Satoshi; Endo, Hitoshi; Tatemichi, Masayuki

2018-04-05

This retrospective cohort study primarily aimed to investigate the possible association of computer use with visual field abnormalities (VFA) among Japanese workers. The study included 2,377 workers (mean age 45.7 [standard deviation, 8.3] years; 2,229 men and 148 women) who initially exhibited no VFA during frequency doubling technology perimetry (FDT) testing. Subjects then underwent annual follow-up FDT testing for 7 years, and VFA were determined using a FDT-test protocol (FDT-VFA). Subjects with FDT-VFA were examined by ophthalmologists. Baseline data about the mean duration of computer use during a 5-year period and refractive errors were obtained via self-administered questionnaire and evaluations for refractive errors (use of eyeglasses or contact lenses), respectively. A Cox proportional hazard analysis demonstrated that heavy computer users (>8 hr/day) had a significantly increased risk of FDT-VFA (hazard ratio [HR] 2.85; 95% confidence interval [CI], 1.26-6.48) relative to light users (<4 hr/day), and this association was strengthened among subjects with refractive errors (HR 4.48; 95% CI, 1.87-10.74). The computer usage history also significantly correlated with FDT-VFA among subject with refractive errors (P < 0.05), and 73.1% of subjects with FDT-VFA and refractive errors were diagnosed with glaucoma or ocular hypertension. The incidence of FDT-VFA appears to be increased among Japanese workers who are heavy computer users, particularly if they have refractive errors. Further investigations of epidemiology and causality are warranted.

Evolution of composition of dairy manure supernatant in a controlled dung pit.

PubMed

Rico, C; García, H; Rico, J L; Fernández, J; Renedo, J

2009-12-01

Anaerobic conversion of dairy manure into biogas is an attractive way of managing this waste. It is well known that the hydrolysis of large molecules into small, directly biodegradable ones is the rate limiting step of the overall anaerobic process. The present work studies the development of the hydrolytic and acidogenic stages of dairy manure with different solid concentrations (40, 60 and 80 g VS/L) at ambient temperature (20 degrees C). The purpose was to determine the operational conditions that provide a liquid fraction with a high soluble chemical oxygen demand (COD) and a high volatile fatty acids (VFA) content in manure before the methanogenic stage starts up. At 20 degrees C, the evolution of the studied parameters showed that, in a controlled plug-flow dung pit, the hydrolytic and acidogenic stages progressed moderately in a continuous way during the 25 days that the experimentation lasted, whereas no methanization was observed. Supernatant COD and VFA concentrations increased 30% and 107%, respectively, for the 60 g VS/L samples. Manure was also operated at 35 degrees C with a similar increase in supernatant COD but a higher increase in VFA, 154%. For both operational temperatures, the predominant VFAs were, in this order, acetic, propionic and butyric acids. During the operation at 35 degrees C, the methanogenic stage started between days 20 and 25 for the samples with lower solids content, i.e. 40 and 60 g VS/L.

Effects of concentrate replacement by feed blocks on ruminal fermentation and microbial growth in goats and single-flow continuous-culture fermenters.

PubMed

Molina-Alcaide, E; Pascual, M R; Cantalapiedra-Hijar, G; Morales-García, E Y; Martín-García, A I

2009-04-01

The effect of replacing concentrate with 2 different feed blocks (FB) on ruminal fermentation and microbial growth was evaluated in goats and in single-flow continuous-culture fermenters. Diets consisted of alfalfa hay plus concentrate and alfalfa hay plus concentrate with 1 of the 2 studied FB. Three trials were carried out with 6 rumen-fistulated Granadina goats and 3 incubation runs in 6 single-flow continuous-culture fermenters. Experimental treatments were assigned randomly within each run, with 2 repetitions for each diet. At the end of each in vivo trial, the rumen contents were obtained for inoculating the fermenters. For each incubation run, the fermenters were inoculated with ruminal fluid from goats fed the same diet supplied to the corresponding fermenter flask. The average pH values, total and individual VFA, and NH(3)-N concentrations, and acetate:propionate ratios in the rumen of goats were not affected (P >or= 0.10) by diet, whereas the microbial N flow (MNF) and efficiency were affected (P or= 0.05), and total (P=0.02), NH(3) (P=0.005), and non-NH(3) (P=0.02) N flows, whereas the efficiency of VFA production was not affected (P=0.75). The effect of diet on MNF and efficiency depended on the bacterial pellet used as a reference. An effect (P<0.05) of diet on the composition of solid- and liquid-associated bacteria was observed. The compositions of liquid-associated bacteria in the fermenter contents and effluent were similar (P=0.05). Differences (P<0.001) between in vivo and in vitro values for most fermentation variables and bacterial pellet compositions were found. Partial replacement of the concentrate with FB did not greatly compromise carbohydrate fermentation in unproductive goats. However, this was not the case for MNF and efficiency. Differences between the results obtained in vivo and in vitro indicate a need to identify conditions in fermenters that allow better simulation of fermentation, microbial growth, and bacterial pellet composition in vivo. Reduced feeding cost could be achieved with the inclusion of FB in the diets of unproductive goats without altering rumen fermentation.

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions

PubMed Central

Belanche, Alejandro; de la Fuente, Gabriel; Newbold, Charles J.

2014-01-01

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H2 sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy. PMID:25764558

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions.

PubMed

Belanche, Alejandro; de la Fuente, Gabriel; Newbold, Charles J

2015-03-01

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H2 sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy. © Federation of European Microbiological Society 2014.

Performance of the full-scale biological nutrient removal plant at Noosa in Queensland, Australia: nutrient removal and disinfection.

PubMed

Urbain, V; Wright, P; Thomas, M

2001-01-01

Stringent effluent quality guidelines are progressively implemented in coastal and sensitive areas in Australia. Biological Nutrient Removal (BNR) plants are becoming a standard often including a tertiary treatment for disinfection. The BNR plant in Noosa - Queensland is designed to produce a treated effluent with less than 5 mg/l of BOD5, 5 mg/l of total nitrogen, 1 mg/l of total phosphorus, 5 mg/l of suspended solids and total coliforms of less than 10/100 ml. A flexible multi-stage biological process with a prefermentation stage, followed by sand filtration and UV disinfection was implemented to achieve this level of treatment. Acetic acid is added for phosphorus removal because: i) the volatile fatty acids (VFA) concentration in raw wastewater varies a lot, and ii) the prefermenter had to be turned off due to odor problems on the primary sedimentation tanks. An endogenous anoxic zone was added to the process to further reduce the nitrate concentration. This resulted in some secondary P-release events, a situation that happens when low nitrate and low phosphorus objectives are targeted. Long-term performance data and specific results on nitrogen removal and disinfection are presented in this paper.

Investigation into the effect of high concentrations of volatile fatty acids in anaerobic digestion on methanogenic communities

PubMed Central

Franke-Whittle, Ingrid H.; Walter, Andreas; Ebner, Christian; Insam, Heribert

2014-01-01

A study was conducted to determine whether differences in the levels of volatile fatty acids (VFAs) in anaerobic digester plants could result in variations in the indigenous methanogenic communities. Two digesters (one operated under mesophilic conditions, the other under thermophilic conditions) were monitored, and sampled at points where VFA levels were high, as well as when VFA levels were low. Physical and chemical parameters were measured, and the methanogenic diversity was screened using the phylogenetic microarray ANAEROCHIP. In addition, real-time PCR was used to quantify the presence of the different methanogenic genera in the sludge samples. Array results indicated that the archaeal communities in the different reactors were stable, and that changes in the VFA levels of the anaerobic digesters did not greatly alter the dominating methanogenic organisms. In contrast, the two digesters were found to harbour different dominating methanogenic communities, which appeared to remain stable over time. Real-time PCR results were inline with those of microarray analysis indicating only minimal changes in methanogen numbers during periods of high VFAs, however, revealed a greater diversity in methanogens than found with the array. PMID:25164858

Effects of rare earth element lanthanum on rumen methane and volatile fatty acid production and microbial flora in vitro.

PubMed

Zhang, T T; Zhao, G Y; Zheng, W S; Niu, W J; Wei, C; Lin, S X

2015-06-01

The objectives of the trial were to study the effects of rare earth element (REE) lanthanum (La) on the in vitro rumen methane (CH4 ) and volatile fatty acid (VFA) production and the microbial flora of feeds. Four feed mixtures with different levels of neutral detergent fibre (NDF), that is 20.0% (I), 31.0% (II), 41.9% (III) and 52.7% (IV), were formulated as substrates. Five levels of LaCl3 , that is 0, 0.4, 0.6, 0.8 and 1.0 mmol/kg dry matter (DM), were added to the feed mixtures, respectively, as experimental treatments in a two-factor 5 × 4 randomized design. The in vitro incubation lasted for 24 h. The results showed that supplementing LaCl3 increased the total gas (p < 0.001) production and tended to increase the total VFA production (p = 0.072) and decreased the CH4 production (p = 0.001) and the ratios of acetate/propionate (p = 0.019) and CH4 /total VFA (p < 0.001). Interactions between LaCl3 and NDF were significant in total gas production (p = 0.030) and tended to be significant in CH4 production (p = 0.071). Supplementing LaCl3 at the level of 0.8 mmol/g DM decreased the relative abundance of methanogens and protozoa in the total bacterial 16S rDNA analysed using the real-time PCR (p < 0.0001), increased F. succinogenes (p = 0.0003) and decreased R. flavefaciens (p < 0.0001) whereas did not affect R. albus and anaerobic fungi (p > 0.05). It was concluded that LaCl3 decreased the CH4 production without negatively affecting feed digestion through manipulating rumen microbial flora when feed mixtures with different levels of NDF were used as substrates. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Improved biogas production from rice straw by co-digestion with kitchen waste and pig manure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Jingqing; School of Environmental Sciences and Engineering, Sun Yat-sen University, Guangzhou 510275; Li, Dong

Highlights: • Biogas production was enhanced by co-digestion of rice straw with other materials. • The optimal ratio of kitchen waste, pig manure and rice straw is 0.4:1.6:1. • The maximum biogas yield of 674.4 L/kg VS was obtained. • VFA inhibition occurred when kitchen waste content was more than 26%. • The dominant VFA were propionate and acetate in successful reactors. - Abstract: In order to investigate the effect of feedstock ratios in biogas production, anaerobic co-digestions of rice straw with kitchen waste and pig manure were carried out. A series of single-stage batch mesophilic (37 ± 1 °C)more » anaerobic digestions were performed at a substrate concentration of 54 g/L based on volatile solids (VS). The results showed that the optimal ratio of kitchen waste, pig manure, and rice straw was 0.4:1.6:1, for which the C/N ratio was 21.7. The methane content was 45.9–70.0% and rate of VS reduction was 55.8%. The biogas yield of 674.4 L/kg VS was higher than that of the digestion of rice straw or pig manure alone by 71.67% and 10.41%, respectively. Inhibition of biogas production by volatile fatty acids (VFA) occurred when the addition of kitchen waste was greater than 26%. The VFA analysis showed that, in the reactors that successfully produced biogas, the dominant intermediate metabolites were propionate and acetate, while they were lactic acid, acetate, and propionate in the others.« less

Soybean oil and linseed oil supplementation affect profiles of ruminal microorganisms in dairy cows.

PubMed

Yang, S L; Bu, D P; Wang, J Q; Hu, Z Y; Li, D; Wei, H Y; Zhou, L Y; Loor, J J

2009-11-01

The objective of this study was to evaluate changes in ruminal microorganisms and fermentation parameters due to dietary supplementation of soybean and linseed oil alone or in combination. Four dietary treatments were tested in a Latin square designed experiment using four primiparous rumen-cannulated dairy cows. Treatments were control (C, 60 : 40 forage to concentrate) or C with 4% soybean oil (S), 4% linseed oil (L) or 2% soybean oil plus 2% linseed oil (SL) in a 4 × 4 Latin square with four periods of 21 days. Forage and concentrate mixtures were fed at 0800 and 2000 h daily. Ruminal fluid was collected every 2 h over a 12-h period on day 19 of each experimental period and pH was measured immediately. Samples were prepared for analyses of concentrations of volatile fatty acids (VFA) by GLC and ammonia. Counts of total and individual bacterial groups (cellulolytic, proteolytic, amylolytic bacteria and total viable bacteria) were performed using the roll-tube technique, and protozoa counts were measured via microscopy in ruminal fluid collected at 0, 4 and 8 h after the morning feeding. Content of ruminal digesta was obtained via the rumen cannula before the morning feeding and used immediately for DNA extraction and quantity of specific bacterial species was obtained using real- time PCR. Ruminal pH did not differ but total VFA (110 v. 105 mmol/l) were lower (P < 0.05) with oil supplementation compared with C. Concentration of ruminal NH3-N (4.4 v. 5.6 mmol/l) was greater (P < 0.05) due to oil compared with C. Compared with C, oil supplementation resulted in lower (P < 0.05) cellulolytic bacteria (3.25 × 108 v. 4.66 × 108 colony-forming units (CFU)/ml) and protozoa (9.04 × 104 v. 12.92 × 104 cell/ml) colony counts. Proteolytic bacteria (7.01 × 108 v. 6.08 × 108 CFU/ml) counts, however, were greater in response to oil compared with C (P < 0.05). Among oil treatments, the amount of Butyrivibrio fibrisolvens, Fibrobacter succinogenes and Ruminococcus flavefaciens in ruminal fluid was substantially lower (P < 0.05) when L was included. Compared to C, the amount of Ruminococcus albus decreased by an average of 40% regardless of oil level or type. Overall, the results indicate that some ruminal microorganisms, except proteolytic bacteria, are highly susceptible to dietary unsaturated fatty acids supplementation, particularly when linolenic acid rich oils were fed. Dietary oil effects on ruminal fermentation parameters seemed associated with the profile of ruminal microorganisms.

Association between abdominal fat distribution and atherosclerotic changes in the carotid artery.

PubMed

Oike, Miki; Yokokawa, Hirohide; Fukuda, Hiroshi; Haniu, Tomomi; Oka, Fukuko; Hisaoka, Teruhiko; Isonuma, Hiroshi

2014-01-01

We aimed to evaluate the association between abdominal fat distribution (e.g., abdominal visceral fat area [VFA], subcutaneous fat area [SFA], and total fat area [TFA]), waist circumference (WC), or body mass index (BMI) and atherosclerotic changes in the carotid artery after adjusting for common risk factors. The present study is a hospital-based, cross-sectional study. Study participants included 223 Japanese individuals who underwent a medical health checkup at Juntendo University Hospital, Tokyo, between December 2005 and August 2011. Multivariate logistic regression analysis was used to examine the association between abdominal VFA, SFA, TFA, the VFA/SFA ratio, WC, or BMI and intima-media thickness [IMT] (mean IMT≥1.1mm or maximum IMT≥1.2mm) as atherosclerotic changes in the carotid artery. Multivariate logistic regression analysis showed that VFA (OR for ≥150cm(2) versus <100cm(2), 3.88; 95% CI, 1.39-10.85), BMI (OR for ≥27.6kg/m(2) versus <25kg/m(2), 5.22; 95% CI, 1.69-16.16), and TFA (OR for 200-285cm(2) versus <200cm(2), 4.15; 95% CI, 1.34-12.86: OR for ≥285cm(2) versus <200cm(2), 5.53; 95% CI, 1.76-17.35) were significantly associated with atherosclerotic changes in men. After adjustment for BMI, only TFA (OR for ≥285cm(2) versus <200cm(2), 3.76; 95%CI, 1.03-13.79) in men was significantly associated with atherosclerotic changes in the carotid artery. Our results indicate that VFA, TFA, and BMI are independently associated with atherosclerotic changes in Japanese men. TFA may be considered as a valuable measure of atherosclerotic changes. Copyright © 2013 Asian Oceanian Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

Effects of Storage Duration and Temperature on the Chemical Composition, Microorganism Density, and In vitro Rumen Fermentation of Wet Brewers Grains

PubMed Central

Wang, B.; Luo, Y.; Myung, K. H.; Liu, J. X.

2014-01-01

This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures (5°C, 15°C, 25°C, and 35°C) and four durations (0, 1, 2, and 3 d) were arranged in a 4×4 factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as 25°C and 35°C. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds 35°C, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above 35°C during summer. PMID:25050021

Association of aqueous hydrogen concentration with methane production in continuous cultures modulated to vary pH and solids passage rate.

PubMed

Wenner, B A; de Souza, J; Batistel, F; Hackmann, T J; Yu, Z; Firkins, J L

2017-07-01

The objective of this study was to evaluate the effects of altering pH and solids passage rate (k p ) on concentration of aqueous H 2 [H 2 (aq)], CH 4 production, volatile fatty acids (VFA) production, and fiber digestibility in a continuous culture fermentation system. The present study was conducted as a 2 × 2 factorial treatment arrangement in a Latin square design using continuous culture fermentors (n = 4). Our continuous culture system was converted to a closed system to measure CH 4 and H 2 emission while measuring H 2 (aq) concentration and VFA production for complete stoichiometric assessment of fermentation pattern. Treatments were control pH (CpH; ranging from 6.3 to 6.9) or low pH (LpH; 5.8 to 6.4) factorialized with solids k p that was adjusted to be either low (Lk p ; 2.5%/h) or high (Hk p ; 5.0%/h); liquid dilution was maintained at 7.0%/h. Fermentors were fed once daily (40 g of dry matter; 50:50 concentrate:forage diet). Four periods lasted 10 d each, with 3 d of sample collection. The main effect of LpH increased nonammonia nitrogen flow, and both LpH and Hk p increased nonammonia nonbacterial N flow. We observed a tendency for Hk p to increase bacterial N flow per unit of nonstructural carbohydrates and neutral detergent fiber degraded. The main effect of LpH decreased H 2 (aq) by 4.33 µM compared with CpH. The main effect of LpH decreased CH 4 production rate from 5 to 9 h postfeeding, and Hk p decreased CH 4 production rate from 3 to 9 h postfeeding. We found no effect of LpH on daily CH 4 production or CH 4 produced per gram of neutral detergent fiber degraded, but Hk p decreased daily CH 4 production by 33.2%. Both the main effects of LpH and Hk p decreased acetate molar percentage compared with CpH and Lk p , respectively. The main effect of both LpH and Hk p increased propionate molar percentage, decreasing acetate-to-propionate ratio from 2.62 to 2.34. We noted no treatment effects on butyrate molar percentage or total VFA production. The results indicate increasing k p and decreasing pH decreased acetate-to-propionate ratio, but only increasing k p decreased CH 4 production; lack of differences for LpH might be a result of compensatory methanogenesis during the second half of the day postfeeding. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of varying dietary starch and fiber levels and inoculum source (mule deer vs. dairy cow) on simulated rumen fermentation characteristics.

PubMed

Brooks, Matthew A; Harvey, Robyn M; Johnson, Nichole F; Koutsos, Elizabeth A; Kerley, Monty S

2014-01-01

This study measured starch and fiber digestion and microbial fermentation of three commercial exotic animal feeds using mule deer (MD) or dairy cow (DC) rumen inoculum. Diets were formulated to provide either high starch/low fiber (based on neutral detergent fiber fraction; NDF) with either alfalfa (diet A) or grain and oilseed byproducts (diet B) as the major fiber sources or low starch/high NDF (diet C). An initial batch culture incubation was run with diets inoculated with each rumen inoculum (n = 6; N = 36) over a 48 hr period with samples taken at different hour points for ammonia, pH, lactate, and volatile fatty acids (VFA). A second experiment was conducted where two continuous culture incubations (MD or DC) were run with six single-flow polycarbonate fermentation vessels per dietary treatment. Diets were fed two times a day over an 8-day period and sampled for ammonia, pH, and VFA before and after feeding on the last 3 days. On day 8, fermenter and effluent contents were collected and analyzed for nitrogen, dry matter digestibility (DMD), and organic matter digestibility (OMD). OMD was greater in MD (P = 0.02) and DMD tended to do the same (P = 0.06), but there were no differences due to diet (P > 0.05). Ammonia concentration was greater in DC (P < 0.01), and diets A and B had greater concentrations than diet C (P < 0.01). The greater digestibility, higher acetate:propionate (A:P) ratio and increased lactate levels prior to feeding likely led to diet C having a lower pH than diet A (6.59 vs. 6.66, respectively; P < 0.01) and led the tendency of A to be lower than C after feeding (P = 0.08). A:P ratio was greater in DC than MD before and after feeding (P < 0.01) and was greater in diet C than diets A or B (P < 0.01). Total VFA production tended to be greater in diets B and C in DC (P = 0.06). Rumen fluid source did affect fermentation. Increasing fiber level did not negatively affect fermentation and may increase OMD by removal of negative associative affects by starch on cellulolytic bacteria. © 2014 Wiley Periodicals, Inc.

Enteric methane production and ruminal fermentation of forage brassica diets fed in continuous culture.

PubMed

Dillard, Sandra Leanne; Roca-Fernández, Ana I; Rubano, Melissa D; Elkin, Kyle R; Soder, Kathy J

2018-04-14

The aim of the current study was to determine nutrient digestibility, VFA production, N metabolism, and CH4 production of canola (Brassica napus L.), rapeseed (B. napus L.), turnip (Brassica rapa L.), and annual ryegrass (Lolium multiflorum Lam.) fed with orchardgrass (Dactylis glomerata L.) in continuous culture. Diets were randomly assigned to fermentors in a 4 × 4 Latin square design using 7 d for adaptation and 3 d for collection. Diets were: 1) 50% orchardgrass + 50% annual ryegrass (ARG); 2) 50% orchardgrass + 50% canola (CAN); 3) 50% orchardgrass + 50% rapeseed (RAP); and 4) 50% orchardgrass + 50% turnip (TUR). Feedings (82 g DM/d) occurred four times daily throughout 4, 10-d periods at 730, 1030, 1400, and 1900 h. Methane samples were collected every 10 min using a photoacoustic gas analyzer (LumaSense Technologies, Inc.; Santa Clara, CA) during the last 3 d of the experiment. Effluent samples were collected on d 8, 9, and 10, composited by fermentor, and analyzed for VFA and pH as well as DM, OM, CP, and fiber fractions for determination of nutrient digestibility. Forage samples were analyzed for CP, NDF, ADF, minerals, and glucosinolate (GLS) concentrations. Data were analyzed using the GLIMMIX procedure of SAS. Apparent DM, OM, and NDF digestibilities and true DM and OM digestibilities were similar (P > 0.28) among diets (45.1, 63.2, 44.1, 67.1, and 87.2%, respectively). Total VFA (87.2 mol/100 mol), pH (6.47), and acetate (A: 44.6 mol/100 mol) were also not different (P > 0.20) among diets. The A:P (P = propionate) ratio was greater (P < 0.01) in ARG and CAN than RAP and TUR. Daily CH4 production was greater (P < 0.01) in ARG than all other diets (68.9 vs. 11.2 mg/d). Methane, whether expressed as g per g of OM, NDF, digestible OM, or digestible NDF fed was greatest (P < 0.01) in ARG but similar (P > 0.18) among brassica diets. A significant negative correlation was observed between total GLS and CH4 production. However, when multiple regression analysis on CH4 production was completed, neither total GLS nor individual GLS were a significant component of the model. Addition of brassicas provided similar nutrient digestibility to ARG while reducing daily CH4 production, potentially making brassicas an alternative for ARG in pasture-based ruminant diets.

Transient changes in milk production efficiency and bacterial community composition resulting from near-total exchange of ruminal contents between high- and low-efficiency Holstein cows.

PubMed

Weimer, Paul J; Cox, Madison S; Vieira de Paula, Tania; Lin, Miao; Hall, Mary Beth; Suen, Garret

2017-09-01

The objectives of this study were to determine if milk production efficiency (MPE) is altered by near-total exchange of ruminal contents between high- (HE) and low-MPE (LE) cows and to characterize ruminal bacterial community composition (BCC) before exchange and over time postexchange. Three pairs of ruminally cannulated, third-lactation cows were selected whose MPE (energy-corrected milk per unit of dry matter intake) differed over their first 2 lactations. Approximately 95% of ruminal contents were exchanged between cows within each pair. Ruminal pH and volatile fatty acid (VFA) profiles, along with BCC (characterized by sequencing of the variable 4 region of 16S rRNA genes), were assessed just before feeding on d -8, -7, -5, -4, -1, 1, 2, 3, 7, 10, 14, 21, 28, 35, 42, and 56, relative to the exchange date. High-MPE cows had higher total ruminal VFA concentrations, higher molar percentages of propionate and valerate, and lower molar percentages of acetate and butyrate than did LE cows, and re-established these differences 1 d after contents exchange. Across all LE cows, MPE increased during 7 d postexchange but declined thereafter. Two of the 3 HE cows displayed decreases in MPE following introduction of the ruminal contents from the corresponding LE cow, but MPE increased in the third HE cow, which was determined to be an outlier. For all 6 cows, both liquid- and solids-associated BCC differed between individuals within a pair before contents exchange. Upon exchange, BCC of both phases in all 3 pairs was more similar to that of the donor inoculum than to preexchange host BCC. For 5 of 6 cows, the solids-associated community returned within 10 d to more resemble the preexchange community of that host than that of the donor community. Individual variability before the exchange was greater in liquids than in solids, as was the variability in response of bacterial communities to the exchange. Individual cows varied in their response, but generally moved toward re-establishment of their preexchange communities by 10 d after contents exchange. By contrast, ruminal pH and VFA profiles returned to preexchange levels within 1 d. Despite the small number of cows studied, the data suggest an apparent role for the ruminal bacterial community as a determinant of MPE. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Methanosarcina as the dominant aceticlastic methanogens during mesophilic anaerobic digestion of putrescible waste.

PubMed

Vavilin, Vasily A; Qu, Xian; Mazéas, Laurent; Lemunier, Melanie; Duquennoi, Christian; He, Pinjing; Bouchez, Theodore

2008-11-01

Taking into account isotope (13)C value a mathematical model was developed to describe the dynamics of methanogenic population during mesophilic anaerobic digestion of putrescible solid waste and waste imitating Chinese municipal solid waste. Three groups of methanogens were considered in the model including unified hydrogenotrophic methanogens and two aceticlastic methanogens Methanosaeta sp. and Methanosarcina sp. It was assumed that Methanosaeta sp. and Methanosarcina sp. are inhibited by high volatile fatty acids concentration. The total organic and inorganic carbon concentrations, methane production, methane and carbon dioxide partial pressures as well as the isotope (13)C incorporation in PSW and CMSW were used for the model calibration and validation. The model showed that in spite of the high initial biomass concentration of Methanosaeta sp. Methanosarcina sp. became the dominant aceticlastic methanogens in the system. This prediction was confirmed by FISH. It is concluded that Methanosarcina sp. forming multicellular aggregates may resist to inhibition by volatile fatty acids (VFAs) because a slow diffusion rate of the acids limits the VFA concentrations inside the Methanosarcina sp. aggregates.

Co-digestion of manure and industrial waste--The effects of trace element addition.

PubMed

Nordell, Erik; Nilsson, Britt; Nilsson Påledal, Sören; Karisalmi, Kaisa; Moestedt, Jan

2016-01-01

Manure is one of the most common substrates for biogas production. Manure from dairy- and swine animals are often considered to stabilize the biogas process by contributing nutrients and trace elements needed for the biogas process. In this study two lab-scale reactors were used to evaluate the effects of trace element addition during co-digestion of manure from swine- and dairy animals with industrial waste. The substrate used contained high background concentrations of both cobalt and nickel, which are considered to be the most important trace elements. In the reactor receiving additional trace elements, the volatile fatty acids (VFA) concentration was 89% lower than in the control reactor. The lower VFA concentration contributed to a more digested digestate, and thus lower methane emissions in the subsequent storage. Also, the biogas production rate increased with 24% and the biogas production yield with 10%, both as a result of the additional trace elements at high organic loading rates. All in all, even though 50% of the feedstock consisted of manure, trace element addition resulted in multiple positive effects and a more reliable process with stable and high yield. Copyright © 2015 Elsevier Ltd. All rights reserved.

Composition of the microbiota in forestomach fluids and feces of Japanese Black calves with white scours.

PubMed

Nakamura, S-I; Kim, Y H; Takashima, K; Kimura, A; Nagai, K; Ichijo, T; Sato, S

2017-09-01

The objective of this study was to characterize the composition of the forestomach and fecal microbiota in Japanese Black calves with white scours. Forestomach fluid, feces, and peripheral blood were collected from healthy calves ( = 5; age 10 ± 2 d) and scouring calves ( = 5; age 10 ± 1 d) on the day on which white scours occurred. The pH and concentrations of VFA, lactic acid, and ammonia nitrogen (NH-N) of the forestomach fluids were determined. Microbiota composition and gene copy numbers in the forestomach fluid and feces were analyzed by 454 pyrosequencing and quantitative real-time PCR (qPCR), respectively. The cytokine mRNA level in peripheral leukocytes was evaluated by qPCR. The pH of the forestomach fluid of the scouring calves tended to be higher than that of the healthy calves ( = 0.056). No significant difference was detected in the total VFA, lactic acid, or NH-N concentrations in the forestomach fluids of the 2 groups. Firmicutes, Bacteroidetes, and Proteobacteria were the predominant phyla in the forestomach fluid and feces. At the genus level, the relative abundance of in the forestomach fluid was significantly higher in the scouring calves ( < 0.05) and the relative abundance of in the feces was significantly higher than that in the forestomach in the healthy calves ( < 0.05). Furthermore, the bacterial diversity indices of feces were lower in the scouring calves. Quantitative PCR amplification using some of the primer pairs failed in the forestomach fluid and feces in both groups. These results suggested that fermentation in the forestomach may affect the occurrence of white scours, resulting in changes in the composition and diversity of the forestomach fluid and fecal microbiota in Japanese Black calves.

Temperature induced decoupling of enzymatic hydrolysis and carbon remineralization in long-term incubations of Arctic and temperate sediments

NASA Astrophysics Data System (ADS)

Robador, Alberto; Brüchert, Volker; Steen, Andrew D.; Arnosti, Carol

2010-04-01

Extracellular enzymatic hydrolysis of high-molecular weight organic matter is the initial step in sedimentary organic carbon degradation and is often regarded as the rate-limiting step. Temperature effects on enzyme activities may therefore exert an indirect control on carbon mineralization. We explored the temperature sensitivity of enzymatic hydrolysis and its connection to subsequent steps in anoxic organic carbon degradation in long-term incubations of sediments from the Arctic and the North Sea. These sediments were incubated under anaerobic conditions for 24 months at temperatures of 0, 10, and 20 °C. The short-term temperature response of the active microbial community was tested in temperature gradient block incubations. The temperature optimum of extracellular enzymatic hydrolysis, as measured with a polysaccharide (chondroitin sulfate), differed between Arctic and temperate habitats by about 8-13 °C in fresh sediments and in sediments incubated for 24 months. In both Arctic and temperate sediments, the temperature response of chondroitin sulfate hydrolysis was initially similar to that of sulfate reduction. After 24 months, however, hydrolysis outpaced sulfate reduction rates, as demonstrated by increased concentrations of dissolved organic carbon (DOC) and total dissolved carbohydrates. This effect was stronger at higher incubation temperatures, particularly in the Arctic sediments. In all experiments, concentrations of volatile fatty acids (VFA) were low, indicating tight coupling between VFA production and consumption. Together, these data indicate that long-term incubation at elevated temperatures led to increased decoupling of hydrolytic DOC production relative to fermentation. Temperature increases in marine sedimentary environments may thus significantly affect the downstream carbon mineralization and lead to the increased formation of refractory DOC.

Effects of Different Types of Exercise on Body Composition, Muscle Strength, and IGF-1 in the Elderly with Sarcopenic Obesity.

PubMed

Chen, Hung-Ting; Chung, Yu-Chun; Chen, Yu-Jen; Ho, Sung-Yen; Wu, Huey-June

2017-04-01

To investigate the influence of resistance training (RT), aerobic training (AT), or combination training (CT) interventions on the body composition, muscle strength performance, and insulin-like growth factor 1 (IGF-1) of patients with sarcopenic obesity. Randomized controlled trial. Community center and research center. Sixty men and women aged 65-75 with sarcopenic obesity. Participants were randomly assigned to RT, AT, CT, and control (CON) groups. After training twice a week for 8 weeks, the participants in each group ceased training for 4 weeks before being examined for the retention effects of the training interventions. The body composition, grip strength, maximum back extensor strength, maximum knee extensor muscle strength, and blood IGF-1 concentration were measured. The skeletal muscle mass (SMM), body fat mass, appendicular SMM/weight %, and visceral fat area (VFA) of the RT, AT, and CT groups were significantly superior to those of the CON group at both week 8 and week 12. Regarding muscle strength performance, the RT group exhibited greater grip strength at weeks 8 and 12 as well as higher knee extensor performance at week 8 than that of the other groups. At week 8, the serum IGF-1 concentration of the RT group was higher than the CON group, whereas the CT group was superior to the AT and CON groups. Older adults with sarcopenic obesity who engaged in the RT, AT, and CT interventions demonstrated increased muscle mass and reduced total fat mass and VFA compared with those without training. The muscle strength performance and serum IGF-1 level in trained groups, especially in the RT group, were superior to the control group. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Influence of the organic loading rate on the performance and the granular sludge characteristics of an EGSB reactor used for treating traditional Chinese medicine wastewater.

PubMed

Li, Weiguang; Su, Chengyuan; Liu, Xingzhe; Zhang, Lei

2014-01-01

The effects of the organic loading rate (OLR) on the performance and the granular sludge characteristics of an expanded granular sludge bed (EGSB) reactor used for treating real traditional Chinese medicine (TCM) wastewater were investigated. Over 90% of the COD removal by the EGSB reactor was observed at the OLRs of 4 to 13 kg COD/(m(3) day). However, increasing the OLR to 20 kg COD/(m(3) day) by reducing the hydraulic retention time (HRT 6 h) reduced the COD removal efficiency to 78%. The volatile fatty acid (VFA) concentration was 512.22 mg/L, resulting in an accumulation of VFAs, and propionic acid was the main acidification product, accounting for 66.51% of the total VFAs. When the OLR increased from 10 to 20 kg COD/(m(3) day), the average size of the granule sludge decreased from 469 to 258 μm. There was an obvious reduction in the concentration of Ca(2+) and Mg(2+) in the granular sludge. The visible humic acid-like peak was identified in the three-dimensional excitation-emission matrix (EEM) fluorescence spectra of the soluble microbial products (SMPs). The fatty acid bond, amide II bond, amide III bond, and C-H bond bending were also observed in the Fourier transform infrared (FTIR) spectra of the SMPs. Methanobacterium formicicum, Methanococcus, and Bacteria populations exhibited significant shifts, and these changes were accompanied by an increase in VFA production. The results indicated that a short HRT and high OLR in the EGSB reactor caused the accumulation of polysaccharides, protein, and VFAs, thereby inhibiting the activity of methanogenic bacteria and causing granular sludge corruption.

A novel process for volatile fatty acids production from syngas by integrating with mesophilic alkaline fermentation of waste activated sludge.

PubMed

Rao, Yue; Wan, Jingjing; Liu, Yafeng; Angelidaki, Irini; Zhang, Shicheng; Zhang, Yalei; Luo, Gang

2018-08-01

The present study proposed and demonstrated a novel process for the bioconversion of syngas (mainly CO and H 2 ) to valuable volatile fatty acids (VFA) by integrating with mesophilic alkaline fermentation of waste activated sludge (WAS). The results showed that although pH 9 was suitable for VFA production from WAS, 62.5% of the consumed CO was converted to methane due to the presence of hydrogenogenic pathway for CO conversion. The increase of pH from 9 to 9.5 inhibited the methane production from CO because of the possible presence of only acetogenic pathway for CO conversion. However, methane was still produced from H 2 contained in syngas through hydrogenotrophic methanogenesis, and around 32-34% of the consumed syngas was converted to methane. At both pH 9 and 9.5, methane was produced by hydrogenotrophic methanogens Methanobacteriales. Further increase of pH to 10 effectively inhibited methane production from syngas, and efficient VFA (mainly acetate with the concentration of around 135 mM) production by simultaneous conversion of syngas and WAS was achieved. High acetate concentrations (>150 mM) were shown to have serious negative effects on the conversion of syngas. The addition of syngas to the mesophilic alkaline fermentation of WAS at pH 10 not only resulted in the enrichment of some known bacteria related with syngas conversion, but also changed the microbial community compositions for the fermentation of WAS. Copyright © 2018 Elsevier Ltd. All rights reserved.

The gas chromatographic determination of volatile fatty acids in wastewater samples: evaluation of experimental biases in direct injection method against thermal desorption method.

PubMed

Ullah, Md Ahsan; Kim, Ki-Hyun; Szulejko, Jan E; Cho, Jinwoo

2014-04-11

The production of short-chained volatile fatty acids (VFAs) by the anaerobic bacterial digestion of sewage (wastewater) affords an excellent opportunity to alternative greener viable bio-energy fuels (i.e., microbial fuel cell). VFAs in wastewater (sewage) samples are commonly quantified through direct injection (DI) into a gas chromatograph with a flame ionization detector (GC-FID). In this study, the reliability of VFA analysis by the DI-GC method has been examined against a thermal desorption (TD-GC) method. The results indicate that the VFA concentrations determined from an aliquot from each wastewater sample by the DI-GC method were generally underestimated, e.g., reductions of 7% (acetic acid) to 93.4% (hexanoic acid) relative to the TD-GC method. The observed differences between the two methods suggest the possibly important role of the matrix effect to give rise to the negative biases in DI-GC analysis. To further explore this possibility, an ancillary experiment was performed to examine bias patterns of three DI-GC approaches. For instance, the results of the standard addition (SA) method confirm the definite role of matrix effect when analyzing wastewater samples by DI-GC. More importantly, their biases tend to increase systematically with increasing molecular weight and decreasing VFA concentrations. As such, the use of DI-GC method, if applied for the analysis of samples with a complicated matrix, needs a thorough validation to improve the reliability in data acquisition. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of 2-hydroxy-4-(methylthio) butanoic acid (HMB) on microbial growth in continuous culture.

PubMed

Noftsger, S M; St-Pierre, N R; Karnati, S K R; Firkins, J L

2003-08-01

2-Hydroxy-4-(methylthio) butanoic acid (HMB) positively affects milk composition and yield, potentially through ruminal actions. Four continuous culture fermenters were used to determine the optimal concentration of HMB for digestibility of organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), and hemicellulose and synthesis of microbial N. A highly degradable mix of hay and grain was used as a basal diet to simulate a typical lactation diet. Three concentrations of HMB (0, 0.055, and 0.110%) and one concentration of dl-Met (0.097%) were infused into the fermenters according to a 4 x 4 Latin square design. Digesta samples were collected during the last 3 d of each of the four 10-d experimental periods. Digestibility of OM, hemicellulose, and NDF was largely insensitive to treatment. Digestibility of ADF showed a quadratic effect to supplementation of HMB, with 0.055% having lower digestibility than 0 or 0.110%. Total production of VFA was not influenced by HMB supplementation, but differences in concentration and production of individual VFA were seen. Isobutyrate increased linearly with increasing HMB supplementation. Propionate concentration decreased linearly with increased HMB supplementation, but propionate production showed a quadratic trend (P = 0.13). A higher concentration of acetate was detected for dl-Met compared with the highest HMB concentration. There were trends (P < 0.15) for dl-Met to decrease the production of isobutyrate and to lower the concentration of butyrate when compared with HMB. Microbial efficiency was not different among treatments. The proportion of bacterial N produced from NH3-N decreased linearly with increasing HMB, and bacteria receiving dl-Met synthesized more N from NH3-N than those receiving HMB. These data suggest that supplementation of HMB may have a sparing effect on branched chain volatile fatty acids because the fatty acids are not needed to provide carbon for synthesis of valine, isoleucine and leucine with ammonia. Comparisons of bacterial community structure in the fermenter effluent samples using PCR amplicons containing the ribosomal intergenic spacer region and its flanking partial 16S ribosomal RNA gene showed no distinct banding patterns, though treatments tended to group together. Both Met and HMB affect the rumen microbial population, but Met supplied as dl-Met does not act identically to that supplied as HMB.

Use of Acetate, Propionate, and Butyrate for Reduction of Nitrate and Sulfate and Methanogenesis in Microcosms and Bioreactors Simulating an Oil Reservoir.

PubMed

Chen, Chuan; Shen, Yin; An, Dongshan; Voordouw, Gerrit

2017-04-01

Acetate, propionate, and butyrate (volatile fatty acids [VFA]) occur in oil field waters and are frequently used for microbial growth of oil field consortia. We determined the kinetics of use of these VFA components (3 mM each) by an anaerobic oil field consortium in microcosms containing 2 mM sulfate and 0, 4, 6, 8, or 13 mM nitrate. Nitrate was reduced first, with a preference for acetate and propionate. Sulfate reduction then proceeded with propionate (but not butyrate) as the electron donor, whereas the fermentation of butyrate (but not propionate) was associated with methanogenesis. Microbial community analyses indicated that Paracoccus and Thauera ( Paracoccus - Thauera ), Desulfobulbus , and Syntrophomonas - Methanobacterium were the dominant taxa whose members catalyzed these three processes. Most-probable-number assays showed the presence of up to 10 7 /ml of propionate-oxidizing sulfate-reducing bacteria (SRB) in waters from the Medicine Hat Glauconitic C field. Bioreactors with the same concentrations of sulfate and VFA responded similarly to increasing concentrations of injected nitrate as observed in the microcosms: sulfide formation was prevented by adding approximately 80% of the nitrate dose needed to completely oxidize VFA to CO 2 in both. Thus, this work has demonstrated that simple time-dependent observations of the use of acetate, propionate, and butyrate for nitrate reduction, sulfate reduction, and methanogenesis in microcosms are a good proxy for these processes in bioreactors, monitoring of which is more complex. IMPORTANCE Oil field volatile fatty acids acetate, propionate, and butyrate were specifically used for nitrate reduction, sulfate reduction, and methanogenic fermentation. Time-dependent analyses of microcosms served as a good proxy for these processes in a bioreactor, mimicking a sulfide-producing (souring) oil reservoir: 80% of the nitrate dose required to oxidize volatile fatty acids to CO 2 was needed to prevent souring in both. Our data also suggest that propionate is a good substrate to enumerate oil field SRB. Copyright © 2017 American Society for Microbiology.

Effects of Gelidium amansii extracts on in vitro ruminal fermentation characteristics, methanogenesis, and microbial populations

PubMed Central

2018-01-01

Objective Gelidium amansii (Lamouroux) is a red alga belonging to the family Gelidaceae and is commonly found in the shallow coasts of many East Asian countries, including Korea, China, and Japan. G. amansii has traditionally been utilized as an edible alga, and has various biological activities. The objective of this study was to determine whether dietary supplementation of G. amansii could be useful for improving ruminal fermentation. Methods As assessed by in vitro fermentation parameters such as pH, total gas, volatile fatty acid (VFA) production, gas profile (methane, carbon dioxide, hydrogen, and ammonia), and microbial growth rate was compared to a basal diet with timothy hay. Cannulated Holstein cows were used as rumen fluid donors and 15 mL rumen fluid: buffer (1:2) was incubated for up to 72 h with four treatments with three replicates. The treatments were: control (timothy only), basal diet with 1% G. amansii extract, basal diet with 3% G. amansii extract, and basal diet with 5% G. amansii extract. Results Overall, the results of our study indicate that G. amansii supplementation is potentially useful for improving ruminant growth performance, via increased total gas and VFA production, but does come with some undesirable effects, such as increasing pH, ammonia concentration, and methane production. In particular, real-time polymerase chain reaction indicated that the methanogenic archaea and Fibrobacter succinogenes populations were significantly reduced, while the Ruminococcus flavefaciens populations were significantly increased at 24 h, when supplemented with G. amansii extracts as compared with controls. Conclusion More research is required to elucidate what G. amansii supplementation can do to improve growth performance, and its effect on methane production in ruminants. PMID:29295611

Effects of Gelidium amansii extracts on in vitro ruminal fermentation characteristics, methanogenesis, and microbial populations.

PubMed

Lee, Shin Ja; Shin, Nyeon Hak; Jeong, Jin Suk; Kim, Eun Tae; Lee, Su Kyoung; Lee, Il Dong; Lee, Sung Sill

2018-01-01

Gelidium amansii (Lamouroux) is a red alga belonging to the family Gelidaceae and is commonly found in the shallow coasts of many East Asian countries, including Korea, China, and Japan. G. amansii has traditionally been utilized as an edible alga, and has various biological activities. The objective of this study was to determine whether dietary supplementation of G. amansii could be useful for improving ruminal fermentation. As assessed by in vitro fermentation parameters such as pH, total gas, volatile fatty acid (VFA) production, gas profile (methane, carbon dioxide, hydrogen, and ammonia), and microbial growth rate was compared to a basal diet with timothy hay. Cannulated Holstein cows were used as rumen fluid donors and 15 mL rumen fluid: buffer (1:2) was incubated for up to 72 h with four treatments with three replicates. The treatments were: control (timothy only), basal diet with 1% G. amansii extract, basal diet with 3% G. amansii extract, and basal diet with 5% G. amansii extract. Overall, the results of our study indicate that G. amansii supplementation is potentially useful for improving ruminant growth performance, via increased total gas and VFA production, but does come with some undesirable effects, such as increasing pH, ammonia concentration, and methane production. In particular, real-time polymerase chain reaction indicated that the methanogenic archaea and Fibrobacter succinogenes populations were significantly reduced, while the Ruminococcus flavefaciens populations were significantly increased at 24 h, when supplemented with G. amansii extracts as compared with controls. More research is required to elucidate what G. amansii supplementation can do to improve growth performance, and its effect on methane production in ruminants.

Storage temperature affects distribution of carbon, VFA, ammonia, phosphorus, copper and zinc in raw pig slurry and its separated liquid fraction.

PubMed

Popovic, Olga; Jensen, Lars Stoumann

2012-08-01

Chemical-mechanical separation of pig slurry into a solid fraction rich in dry matter, P, Cu and Zn and a liquid fraction rich in inorganic N but poor in dry matter may allow farmers to manage surplus slurry by exporting the solid fraction to regions with no nutrient surplus. Pig slurry can be applied to arable land only in certain periods during the year, so it is commonly stored prior to field application. This study investigated the effect of storage duration and temperature on chemical characteristics and P, Cu and Zn distribution between particle size classes of raw slurry and its liquid separation fraction. Dry matter, VFA, total N and ammonium content of both slurry products decreased during storage and were affected by temperature, showing higher losses at higher storage temperatures. In both products, total P, Cu and Zn concentrations were not significantly affected by storage duration or temperature. Particle size distribution was affected by slurry separation, storage duration and temperature. In raw slurry, particles larger than 1 mm decreased, whereas particles 250 μm-1 mm increased. The liquid fraction produced was free of particles >500 μm, with the highest proportions of P, Cu and Zn in the smallest particle size class (<25 μm). The proportion of particles <25 μm increased when the liquid fraction was stored at 5 °C, but decreased at 25 °C. Regardless of temperature, distribution of P, Cu and Zn over particle size classes followed a similar pattern to dry matter. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vertebral Fracture Assessment by dual-energy X-ray absorptiometry: insurance coverage issues in the United States. A White Paper of the International Society for Clinical Densitometry.

PubMed

Laster, Andrew J; Lewiecki, E Michael

2007-01-01

Clinical trial data and fracture risk prediction models unequivocally demonstrate the utility of identifying prevalent vertebral fractures to predict future fractures of all types. Knowledge of prevalent vertebral fractures can alter patient management decisions and result in initiation of therapy to reduce fracture risk in some patients who would not otherwise be treated. Cost-benefit analysis demonstrates that identifying and treating patients with vertebral fractures, even those with a densitometric classification of osteopenia, is cost effective. Vertebral fractures can be readily identified in the office setting using standard radiography or Vertebral Fracture Assessment (VFA), a software addition to a central dual-energy X-ray absorptiometry (DXA) machine. In the United States, VFA was assigned a Current Procedural Terminology (CPT) code in January 2005. Nevertheless, coverage of VFA has not been uniformly embraced by Medicare carriers, companies that contract with the federal government to administer Medicare coverage and process claims for a region of the United States. Unlike DXA, for which uniform national coverage of qualified Medicare beneficiaries is mandated by the Balanced Budget Act of 1997, VFA coverage policies are determined by the local Medicare carriers. Third-party insurers are also variable in their coverage of VFA. This International Society for Clinical Densitometry (ISCD) White Paper documents the role of VFA in the evaluation and treatment of women with postmenopausal osteoporosis and compares it with standard spine radiography. Arguments used by some Medicare carriers and insurers to deny coverage of VFA in the United States are analyzed and critiqued. For health care providers within the United States, this White Paper may serve as a resource to respond to insurers who deny coverage of VFA. For health care providers regardless of their country, this article underscores the value of VFA as an alternative to spine radiography in the evaluation and management of postmenopausal women with suspected osteoporosis.

Effects of a 3 strain -based direct-fed microbial and dietary fiber concentration on growth performance and expression of genes related to absorption and metabolism of volatile fatty acids in weanling pigs.

PubMed

Jaworski, N W; Owusu-Asiedu, A; Walsh, M C; McCann, J C; Loor, J J; Stein, H H

2017-01-01

Effects of a -based direct-fed microbial (DFM) on growth performance, plasma tumor necrosis factor ɑ (TNFɑ), relative gene expression, and intestinal VFA concentrations in weanling pigs fed low- or high-fiber diets were evaluated. Two hundred pigs (initial BW: 6.31 ± 0.73 kg) were allotted to 1 of 4 dietary treatments (5 pigs per pen and 10 pens per treatment). Treatments were arranged in a 2 × 2 factorial design with 2 diet types [low-fiber (LF) or high-fiber (HF)] and 2 concentrations of DFM (0 or 60 g DFM/t of feed). The DFM contained 1.5 × 10 cfu/g and was obtained from Danisco Animal Nutrition-DuPont Industrial Biosciences, Marlborough, UK. Phase 1 diets were fed for 2 wk post-weaning and phase 2 diets were fed over the following 29 d. Low fiber diets contained corn and soybean meal as main ingredients and HF diets contained corn, soybean meal, corn distillers dried grains with solubles (7.5 and 15.0% in phase 1 and 2, respectively), and wheat middlings (10.0%). Pigs and feed were weighed at the start and at the end of each phase, and ADG, ADFI, and G:F were calculated. At the conclusion of phase 2, blood was collected from 1 pig per pen and 1 pig per pen was sacrificed. Cecum and rectum contents were analyzed for VFA, and tissue samples were collected from the ileum, cecum, rectum, and liver to determine expression of genes related to absorption and metabolism of VFA using quantitative reverse transcription-PCR. Results indicated that feeding HF diets reduced ( ≤ 0.05) ADFI and ADG of pigs compared with feeding LF diets. Pigs fed DFM diets had improved ( ≤ 0.05) G:F compared with pigs fed non-DFM diets. Pigs fed LF diets had greater ( ≤ 0.05) BW at the end of phase 2 compared with pigs fed HF diets. The concentration of VFA in rectum contents was greater ( ≤ 0.05) in pigs fed LF diets than in pigs fed HF diets. The expression of in the rectum of pigs fed HF diets was greater ( ≤ 0.05) than for pigs fed LF diets, and pigs fed DFM-containing diets had an increased ( ≤ 0.05) expression of in the liver. Pigs fed HF diets had greater ( ≤ 0.05) concentrations of urea N in plasma compared with pigs fed LF diets, but dietary fiber and DFM had no effect on plasma concentration of TNF-ɑ. In conclusion, the -based DFM improved overall G:F of weanling pigs, but pigs fed LF diets had greater final BW than pigs fed HF diets.

Visceral fat area is associated with HbA1c but not dialysate-related glucose load in nondiabetic PD patients

NASA Astrophysics Data System (ADS)

Ho, Li-Chun; Yen, Chung-Jen; Chao, Chia-Ter; Chiang, Chih-Kang; Huang, Jenq-Wen; Hung, Kuan-Yu

2015-08-01

Factors associated with increased visceral fat area (VFA) have been well documented in the general population but rarely explored in nondiabetic individuals on peritoneal dialysis (PD). As glycosylated hemoglobin (HbA1c) is positively correlated with VFA in diabetic patients, we hypothesized that the same correlation would exist in nondiabetic PD patients. We enrolled 105 nondiabetic patients who had undergone chronic PD for more than 3 months. Each subject underwent an abdominal computed tomography (CT) scan, and the umbilicus cut was analyzed for VFA. VFA values, corrected for body mass index and subjected to natural logarithm transformations, were examined to determine whether they were correlated with HbA1c and other parameters. PD dialysates prescribed at the time of enrollment were recorded to calculate glucose load. We found that when 105 nondiabetic PD patients were classified according to tertiles of HbA1c, higher HbA1c was associated with larger VFA. Multiple linear regression analysis revealed that HbA1c was an independent determinant of VFA, while glucose load and other PD-specific factors were not. In summary, HbA1c, but not PD-related glucose load, was positively correlated with VFA in nondiabetic PD patients, suggesting clinical utility of HbA1c in the PD population.

Oriented acidification of wasted activated sludge (WAS) focused on odd-carbon volatile fatty acid (VFA): Regulation strategy and microbial community dynamics.

PubMed

Huang, Long; Chen, Zhiqiang; Xiong, Dandan; Wen, Qinxue; Ji, Ye

2018-06-01

As the main intermediate metabolite in anaerobic digestion of wasted activated sludge (WAS), volatile fatty acids (VFAs) are proper substrate for mixed culture (MC) polyhydroxyalkanoate (PHA) synthesis. To further optimize the performance of MC PHA production process, VFA _odd (i.e., VFA with odd carbon atoms) oriented acidification process was proposed and conducted in this study. Three regulation factors including reaction pH, fraction of added β-cyclodextrin (β-CD) and glycerol were selected and response surface methodology (RSM) was used to enhance and effectively regulate the VFA _odd production while maintaining enough acidification degree in the WAS acidification. High percentage of VFA _odd (larger than 60% and dominated by propionic acid) can be obtained in the operating condition area with glycerol addition ratio (quantified by C/N) ranging from 15 to 20 and reaction pH ranging from 8.0 to 9.5 when β-CD addition was held at zero level (0.2 g/gTSS) according to the RSM. Semi-continuous acidification and MC PHA production assays further verified the reliability and effectiveness of the VFA _odd oriented acidification strategy. Microbial function group related to propionic acid production (G prop ) was defined based on the relationships between system function and microbial community structure, and 13 frequent species were found being involved in the G prop . Roles of the group members in the oriented acidification were analyzed to understand the mechanisms of the regulation of VFA _odd production at microbial ecological level. A synergistic effect of WAS and glycerol on the VFA _odd production in the acidification process was revealed based on the ecological analysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vascular and metabolic effects of ezetimibe combined with simvastatin in patients with hypercholesterolemia.

PubMed

Koh, Kwang Kon; Oh, Pyung Chun; Sakuma, Ichiro; Kim, Eun Young; Lee, Yonghee; Hayashi, Toshio; Han, Seung Hwan; Park, Yae Min; Shin, Eak Kyun

2015-11-15

Ezetimibe demonstrates decreasing visceral fat and improving insulin sensitivity (IS) in animals and humans. We first reported that simvastatin dose-dependently worsens insulin sensitivity. Whether ezetimibe may compensate untoward effects of simvastatin, depending on dosages of simvastatin has not been investigated in patients with hypercholesterolemia, compared with simvastatin alone. This was a randomized, single-blind, placebo-controlled, parallel study. Fifty-one in each group were given placebo, ezetimibe 10mg combined with simvastatin 10mg (Vyto10), ezetimibe 10mg combined with simvastatin 20mg (Vyto20), or simvastatin 20mg alone (Simva20) daily for 2months. Placebo, Vyto10, Vyto20, and Simva20 improved flow-mediated dilation relative to baseline measurements. Placebo therapy did not significantly change insulin and IS and adiponectin levels and visceral fat area (VFA) and VFA/subcutaneous fat area (SFA) relative to baseline measurements. Vyto10 therapy significantly decreased CRP and insulin levels and increased adiponectin levels and IS, and reduced VFA, VFA/SFA, and blood pressure. Vyto20 therapy did not significantly change insulin levels and IS and adiponectin levels but significantly reduced CRP levels and VFA, VFA/SFA, and blood pressure. Simva20 therapy significantly decreased adiponectin levels and IS but did not significantly change VFA, VFA/SFA, and blood pressure. Of note, these different effects of each therapy were significant by ANOVA. Vyto10, Vyto20, and Simva20 showed significant reduction of LDL cholesterol levels and improvement of flow-mediated dilation in patients with hypercholesterolemia. However, Vyto10, Vyto20, and Simva20 showed significantly differential metabolic effects, depending on dosages of simvastatin. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effects of Saccharomyces cerevisiae fermentation product on in vitro fermentation and microbial communities of low-quality forages and mixed diets.

PubMed

Mao, Hui-ling; Mao, Hua-long; Wang, J K; Liu, J X; Yoon, I

2013-07-01

Two experiments were conducted to investigate the effects of a Saccharomyces cerevisiae fermentation product (XP, Diamond V, Cedar Rapids, IA) on in vitro ruminal fermentation of single forage and mixed diets. In Exp. 1, an in vitro test was used to determine the effects of various concentrations (0, 1, 2, and 3 g/L) of XP on ruminal fermentation of the major forage sources of China (rice straw, RS; corn stover, CS; corn silage without grain, CSNG; and corn silage with grain, CSG). Total VFA reached a peak at 1 g/L XP for RS, CSNG, and CSG and increased linearly (P < 0.01) for CS. The molar proportion of acetate decreased and propionate increased linearly (P < 0.01) with an increasing amount of XP for RS, CS, and CSNG. Microbial protein (MCP) increased linearly (P < 0.01) with an increasing level of XP for RS, and it reached peak values at 1 and 2 g/L XP for CSG and CSNG, respectively. Fungi population was increased (P < 0.05) with 1 g/L XP for all forages except CSNG. The population of Ruminococcus flavefaciens increased (P < 0.05) at 1 or 2 g/L XP for RS, CSNG, and CSG. In Exp. 2, the effects of 3 concentrations of XP (0, 1, and 2 g/L) were tested on in vitro ruminal fermentation of 3 mixed diets with various ingredient combinations: 1) CSC (corn:soybean meal:corn stover = 33:22:45), 2) CSCC (corn:soybean meal:corn stover:corn silage = 33:22:22.5:22.5), and 3) CSCCA (corn:soybean meal:corn stover:corn silage:alfalfa = 33:22:19:21:5). Total VFA concentrations were influenced by diets (P < 0.01) and were enhanced linearly by increasing concentrations of XP (P < 0.01). The molar proportion of acetate was reduced (P < 0.01), but the propionate proportion was enhanced with increasing concentrations of XP (P < 0.01). Ammonia N was decreased and MCP was increased by the addition of XP (linear, P < 0.01; quadratic, P < 0.05). The fungi population was greater with XP addition (quadratic, P < 0.01). The percentage of R. albus was affected by diets (P < 0.01), the level of XP (linear and quadratic, P < 0.01), and their interaction (P < 0.01). From these 2 in vitro studies, it is inferred that the addition of XP could improve the rumen fermentation of forages and mixed diets by stimulating the number of fiber-digesting rumen microbes, especially fungi populations.

Mechanical sludge disintegration for the production of carbon source for biological nutrient removal.

PubMed

Kampas, P; Parsons, S A; Pearce, P; Ledoux, S; Vale, P; Churchley, J; Cartmell, E

2007-04-01

The primary driver for a successful biological nutrient removal is the availability of suitable carbon source, mainly in the form of volatile fatty acids (VFA). Several methods have been examined to increase the amount of VFAs in wastewater. This study investigates the mechanism of mechanical disintegration of thickened surplus activated sludge by a deflaker technology for the production of organic matter. This equipment was able to increase the soluble carbon in terms of VFA and soluble chemical oxygen demand (SCOD) with the maximum concentration to be around 850 and 6530 mgl(-1), for VFA and SCOD, respectively. The particle size was reduced from 65.5 to 9.3 microm after 15 min of disintegration with the simultaneous release of proteins (1550 mgl(-1)) and carbohydrates (307 mgl(-1)) indicating floc disruption and breakage. High performance size exclusion chromatography investigated the disintegrated sludge and confirmed that the deflaker was able to destroy the flocs releasing polymeric substances that are typically found outside of cells. When long disintegration times were applied (>or=10 min or >or=9000 kJkg(-1)TS of specific energy) smaller molecular size materials were released to the liquid phase, which are considered to be found inside the cells indicating cell lysis.

Methanogenesis at low temperatures by microflora of tundra wetland soil.

PubMed

Kotsyurbenko, O R; Nozhevnikova, A N; Soloviova, T I; Zavarzin, G A

1996-01-01

Active methanogenesis from organic matter contained in soil samples from tundra wetland occurred even at 6 degrees C. Methane was the only end product in balanced microbial community with H2/CO2 as a substrate, besides acetate was produced as an intermediate at temperatures below 10 degrees C. The activity of different microbial groups of methanogenic community in the temperature range of 6-28 degrees C was investigated using 5% of tundra soil as inoculum. Anaerobic microflora of tundra wetland fermented different organic compounds with formation of hydrogen, volatile fatty acids (VFA) and alcohols. Methane was produced at the second step. Homoacetogenic and methanogenic bacteria competed for such substrates as hydrogen, formate, carbon monoxide and methanol. Acetogens out competed methanogens in an excess of substrate and low density of microbial population. Kinetic analysis of the results confirmed the prevalence of hydrogen acetogenesis on methanogenesis. Pure culture of acetogenic bacteria was isolated at 6 degrees C. Dilution of tundra soil and supply with the excess of substrate disbalanced the methanoigenic microbial community. It resulted in accumulation of acetate and other VFA. In balanced microbial community obviously autotrophic methanogens keep hydrogen concentration below a threshold for syntrophic degradation of VFA. Accumulation of acetate- and H2/CO2-utilising methanogens should be very important in methanogenic microbial community operating at low temperatures.

Optimization of volatile fatty acid production with co-substrate of food wastes and dewatered excess sludge using response surface methodology.

PubMed

Hong, Chen; Haiyun, Wu

2010-07-01

Central-composite design (CCD) and response surface methodology (RSM) were used to optimize the parameters of volatile fatty acid (VFA) production from food wastes and dewatered excess sludge in a semi-continuous process. The effects of four variables (food wastes composition in the co-substrate of food wastes and excess sludge, hydraulic retention time (HRT), organic loading rate (OLR), and pH) on acidogenesis were evaluated individually and interactively. The optimum condition derived via RSM was food wastes composition, 88.03%; HRT, 8.92 days; OLR, 8.31 g VSS/ld; and pH 6.99. The experimental VFA concentration was 29,099 mg/l under this optimum condition, which was well in agreement with the predicted value of 28,000 mg/l. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Bicarbonate secretion and solute absorption in forestomach of the llama.

PubMed

Rübsamen, K; Engelhardt, W V

1978-07-01

Bicarbonate appearance in the lumen and its relationship to solute absorption were studied in a Pavlov pouch in the cardiac region of the first compartment of the llama forestomach. HCO3- appearance showed no diurnal variation. HCO3- accumulation was highly dependent on the pH of the solution used. The HCO3- ion probably is formed from CO2 diffusing into the lumen from the serosal side, as a result of cell metabolism and of OH- ions. HCO3- accumulation was closely related to volatile fatty acid (VFA) absorption. The ratio of HCO3- appearance to VFA absorption depended on the pH of the solution. At a pH of 6.6, about 0.1 mol HCO3- and, at a pH of 7.8, 0.9 mol HCO3- appeared per mole absorbed VFA, indicating that at slightly alkaline pH nearly all H+ ions required for the nonionic absorption of VFA appeared to be delivered from the dissociation of H2CO3. Bicarbonate gain and VFA absorption were increased when animals were not fed for 48 h. Sodium absorption was related to VFA as well as water absorption.

Effect of dietary crude protein levels in a commercial range, on the nitrogen balance, ammonia emission and pollutant characteristics of slurry in fattening pigs.

PubMed

Hernández, F; Martínez, S; López, C; Megías, M D; López, M; Madrid, J

2011-06-01

An experiment was conducted to investigate the effect of dietary levels of crude protein (CP), close to the range used commercially and to the European Commission recommended values, on the nitrogen (N) balance, ammonia (NH(3)) emission and pollutant characteristics of the slurry from growing and finishing pigs. Three feeding programmes with different CP levels were compared during the growing and the finishing periods of fattening. Diets were formulated to be isoenergetic and for the digestible lysine : metabolisable energy ratio to be similar in all the diets for each phase, but differed in CP concentration (160, 150 and 140 g CP/kg for the growing phase and 155, 145 and 135 g CP/kg for the finishing phase). Faeces and urine from barrows (eight replicates per diet) allocated in metabolism cages were collected separately for 5 days to calculate the N balance and for 2 days to measure NH(3) emission in a laboratory system for 240 h. Excreta were analysed for pH, volatile fatty acids (VFA), total N, electrical conductivity (EC), total solids (TS), volatile solids (VS), biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD) and NH(4)-N reduction of dietary CP content led to a linear decrease of urinary (P < 0.05) and total (P < 0.05) N excretion, and N excretion/feed intake (P < 0.001). The emission of NH3 was similar in all diets (P > 0.05) during the 240 h of study. However, in the growing phase, the NH(3)-N level in slurry was lower (P < 0.05) for the low-CP diet. In addition, the CP level had no significant effect (P > 0.05) on total VFA, EC, TS, VS, COD or BOD(5) contents of excreta. These parameters were higher (P < 0.05) in slurry from the finishing phase than from the growing phase. However, NH(4)-N in the slurry decreased (P < 0.05) by 20.3% and 28.4% when the CP level was decreased by 9.30 or 21.40 g/kg, respectively. It is concluded that lowering dietary CP levels even by small amounts and using CP levels close to these used in commercial diets and close to the European Commission recommended values will decrease urinary and total N excretion in the slurry of growing-finishing pigs. The slurry from finishing pigs is more concentrated than that from growing pigs.

Effects of Flavonoids on Rumen Fermentation Activity, Methane Production, and Microbial Population

PubMed Central

Abdullah, Norhani; Oskoueian, Armin

2013-01-01

This research was carried out to evaluate the effects of flavone, myricetin, naringin, catechin, rutin, quercetin, and kaempferol at the concentration of 4.5% of the substrate (dry matter basis) on the rumen microbial activity in vitro. Mixture of guinea grass and concentrate (60 : 40) was used as the substrate. The results showed that all the flavonoids except naringin and quercetin significantly (P < 0.05) decreased the dry matter degradability. The gas production significantly (P < 0.05) decreased by flavone, myricetin, and kaempferol, whereas naringin, rutin, and quercetin significantly (P < 0.05) increased the gas production. The flavonoids suppressed methane production significantly (P < 0.05). The total VFA concentration significantly (P < 0.05) decreased in the presence of flavone, myricetin, and kaempferol. All flavonoids except naringin and quercetin significantly (P < 0.05) reduced the carboxymethyl cellulase, filter paperase, xylanase, and β-glucosidase activities, purine content, and the efficiency of microbial protein synthesis. Flavone, myricetin, catechin, rutin, and kaempferol significantly (P < 0.05) reduced the population of rumen microbes. Total populations of protozoa and methanogens were significantly (P < 0.05) suppressed by naringin and quercetin. The results of this research demonstrated that naringin and quercetin at the concentration of 4.5% of the substrate (dry matter basis) were potential metabolites to suppress methane production without any negative effects on rumen microbial fermentation. PMID:24175289

Effect of urea treatment of cocoa pod on rumen fermentation characteristics in vitro

NASA Astrophysics Data System (ADS)

Anggraeni, A. S.; Herdian, H.; Sakti, A. A.; Sofyan, A.; Ekaningrum, M.

2017-12-01

Indonesia is a third largest country in the world for cocoa production. A cocoa pod could be utilized as alternative feeds due to their sufficient quantity and availability throughout the year. On the other hand, low nutritional quality such as highly fibrous materials and low protein content usually characterized in agricultural and plantation by-products as it appears on cocoa pod. Ammoniation treatment using urea improve the nutritional quality of feedstuff. The objective of this study was to evaluate the effect of ammoniation treatments on a cocoa pod on in vitro feed fermentation and gas production on ruminal fluid. KA treatment gave highest gas production than other treatment. Total gas production during 48 hours of the cocoa pod was significantly affected by treatments (P<0.05). Total volatile acid (VFA), acetate (C2), propionate (C3), butyrate (C4) total VFA and A/P ratio indicated no significant difference among treatments. KA and KD treatments have tendency effect on IVDMD than control (KS) treatment. In this study ammoniation treatment using 5% of urea had a positive and effect on the best degradability and ruminal fermentation of cocoa pod.

Implementation of in-line infrared monitor in full-scale anaerobic digestion process.

PubMed

Spanjers, H; Bouvier, J C; Steenweg, P; Bisschops, I; van Gils, W; Versprille, B

2006-01-01

During start up but also during normal operation, anaerobic reactor systems should be run and monitored carefully to secure trouble-free operation, because the process is vulnerable to disturbances such as temporary overloading, biomass wash out and influent toxicity. The present method of monitoring is usually by manual sampling and subsequent laboratory analysis. Data collection, processing and feedback to system operation is manual and ad hoc, and involves high-level operator skills and attention. As a result, systems tend to be designed at relatively conservative design loading rates resulting in significant over-sizing of reactors and thus increased systems cost. It is therefore desirable to have on-line and continuous access to performance data on influent and effluent quality. Relevant variables to indicate process performance include VFA, COD, alkalinity, sulphate, and, if aerobic post-treatment is considered, total nitrogen, ammonia and nitrate. Recently, mid-IR spectrometry was demonstrated on a pilot scale to be suitable for in-line simultaneous measurement of these variables. This paper describes a full-scale application of the technique to test its ability to monitor continuously and without human intervention the above variables simultaneously in two process streams. For VFA, COD, sulphate, ammonium and TKN good agreement was obtained between in-line and manual measurements. During a period of six months the in-line measurements had to be interrupted several times because of clogging. It appeared that the sample pre-treatment unit was not able to cope with high solids concentrations all the time.

Treatment of low-strength soluble wastewater using an anaerobic baffled reactor (ABR).

PubMed

Gopala Krishna, G V T; Kumar, Pramod; Kumar, Pradeep

2009-01-01

Treatment of low-strength soluble wastewater (COD approximately 500 mg/L) was studied using an eight chambered anaerobic baffled reactor (ABR). At pseudo steady-state (PSS), the average total and soluble COD values (COD(T) and COD(S)) at 8h hydraulic retention time (HRT) were found to be around 50 and 40 mg/L, respectively, while at 10h HRT average COD(T) and COD(S) values were of the order of 47 and 37 mg/L, respectively. COD and BOD (3 day, 27 degrees C) removal averaged more than 90%. Effluent conformed to Indian standards laid down for BOD (less than 30 mg/L). Reactor effluent characteristics exhibited very low values of standard deviation indicating excellent reactor stability at PSS in terms of effluent characteristics. Based on mass balance calculations, more than 60% of raw wastewater COD was estimated to be recovered as CH(4) in the gas phase. Compartment-wise profiles indicated that most of the BOD and COD got reduced in the initial compartments only. Sudden drop in pH (7.8-6.7) and formation of volatile fatty acids (VFA) (53-85 mg/L) were observed in the first compartment due to acidogenesis and acetogenesis. The pH increased and VFA concentration decreased longitudinally down the reactor. Residence time distribution (RTD) studies revealed that the flow pattern in the ABR was neither completely plug-flow nor perfectly mixed. Observations from scanning electron micrographs (SEM) suggest that distinct phase separation takes place in an ABR.

Continuous operation of thermophilic food waste digestion with side-stream ammonia stripping.

PubMed

Zhang, Wei; Heaven, Sonia; Banks, Charles J

2017-11-01

Digesters fed on food waste (high nitrogen content) were operated successfully over an extended period using sidestream biogas stripping to control total ammonia nitrogen (TAN) below inhibitory concentrations. This is the first time biogas stripping has been used to achieve stable thermophilic operation with undiluted substrate of this type. Stripping columns operated batch-wise treated the equivalent of 1.7-4.1% of digester contents daily at pH >10 and 70°C, with no detrimental effect on digestion. TKN removal was 54%, with potential to recover 3.5kgNtonne -1 substrate. When stripping was stopped in one digester TAN increased, accompanied by rising propionic acid concentrations with progressive instability observed from 2.5gNL -1 . Eventual failure as TAN approached 5gNL -1 was due to rapid acetic acid accumulation, resulting in a fall in pH to below 6.5. The pattern of VFA accumulation indicated failure of both acetoclastic methanogenesis and acetate oxidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anaerobic digestion of blackwater from vacuum toilets and kitchen refuse in a continuous stirred tank reactor (CSTR).

PubMed

Wendland, C; Deegener, S; Behrendt, J; Toshev, P; Otterpohl, R

2007-01-01

The objective of this research was mesophilic anaerobic digestion of blackwater from vacuum toilets (BW) and kitchen refuse (KR) in a CSTR within an ecological sanitation system. A detailed investigation of the BW characteristics was carried out. Research on anaerobic digestion was performed with CSTR of 101 volume at HRT of 10, 15 and 20 days. The digestion of BW at 20 days HRT showed stable performance without inhibition effects, in spite of relatively high ammonium concentrations. The removal of total and particulate COD was 61% and 53%, respectively, and the methane yield 10/CH4/cap/day. The addition of kitchen refuse (KR) improved the performance of the CSTR in terms of COD removal efficiency and methane yield. At 20 days HRT the removal of total and particulate COD increased up to 71% and 67%, respectively, and the methane yield to 27/CH4/cap/day. The results at 15 days HRT showed similar performance. At HRT of 10 days, the anaerobic treatment was limited but reached steady state conditions at higher VFA concentrations in the effluent, with a decrease of COD removal of 30 to 33% and of methane yields of 19 to 21%.

A High Grain Diet Dynamically Shifted the Composition of Mucosa-Associated Microbiota and Induced Mucosal Injuries in the Colon of Sheep.

PubMed

Wang, Yue; Xu, Lei; Liu, Junhua; Zhu, Weiyun; Mao, Shengyong

2017-01-01

This study investigated the dynamic shifts in mucosa-associated microbiota composition and mucosal morphology in the colon of sheep fed a high grain (HG) diet. A total of 20 male sheep were randomly assigned to four groups ( n = 5 for each). The sheep in first group received hay diet. The animals in other 3 groups were fed an HG diet for 7 (HG7), 14 (HG14), or 28 (HG28) days, respectively. Colonic digesta samples were collected to determine the pH and the concentrations of volatile fatty acid (VFA) and lactate. The colonic mucosa was sampled to characterize the bacterial communities using Illumina MiSeq sequencing and to determine mRNA expression levels of cytokines and tight junction protein genes using quantitative real-time PCR. As time advanced, results revealed that colonic pH linearly decreased ( P = 0.007), and the concentrations of total VFA linearly increased ( P < 0.001). Microbial analysis showed that an HG diet linearly reduced ( P < 0.050) the diversity and richness of the colonic microbiota. The principal coordinate analysis results showed that the colonic mucosa-associated bacterial communities of the four groups significantly shifted with number of days fed an HG diet. At the genus level, HG feeding significantly increased the relative abundance of some taxa including Prevotella , Coprococcus , Roseburia , and Clostridium_sensu_stricto_1 , and decreased the proportion of Treponema, and the percentage of these taxa was not affected by days fed an HG diet. The microscopic examination showed that HG feeding caused the mucosal epithelial injury. The RT-PCR results showed that the mRNA expression of claudin-1 ( P = 0.038), IL-1β ( P = 0.045), IL-6 ( P = 0.050), and TNF-α ( P = 0.020) increased linearly with number of days fed an HG diet. The correlation analysis revealed significant correlation between the colonic mucosal mRNA expression of cytokines and mucosal bacterial composition. Generally, HG feeding increased colonic fermentation and altered colonic mucosal bacterial communities, which eventually caused colonic mucosal damage and led to colonic dysfunction, and these changes occurred gradually over at least 4 weeks.

A High Grain Diet Dynamically Shifted the Composition of Mucosa-Associated Microbiota and Induced Mucosal Injuries in the Colon of Sheep

PubMed Central

Wang, Yue; Xu, Lei; Liu, Junhua; Zhu, Weiyun; Mao, Shengyong

2017-01-01

This study investigated the dynamic shifts in mucosa-associated microbiota composition and mucosal morphology in the colon of sheep fed a high grain (HG) diet. A total of 20 male sheep were randomly assigned to four groups (n = 5 for each). The sheep in first group received hay diet. The animals in other 3 groups were fed an HG diet for 7 (HG7), 14 (HG14), or 28 (HG28) days, respectively. Colonic digesta samples were collected to determine the pH and the concentrations of volatile fatty acid (VFA) and lactate. The colonic mucosa was sampled to characterize the bacterial communities using Illumina MiSeq sequencing and to determine mRNA expression levels of cytokines and tight junction protein genes using quantitative real-time PCR. As time advanced, results revealed that colonic pH linearly decreased (P = 0.007), and the concentrations of total VFA linearly increased (P < 0.001). Microbial analysis showed that an HG diet linearly reduced (P < 0.050) the diversity and richness of the colonic microbiota. The principal coordinate analysis results showed that the colonic mucosa-associated bacterial communities of the four groups significantly shifted with number of days fed an HG diet. At the genus level, HG feeding significantly increased the relative abundance of some taxa including Prevotella, Coprococcus, Roseburia, and Clostridium_sensu_stricto_1, and decreased the proportion of Treponema, and the percentage of these taxa was not affected by days fed an HG diet. The microscopic examination showed that HG feeding caused the mucosal epithelial injury. The RT-PCR results showed that the mRNA expression of claudin-1 (P = 0.038), IL-1β (P = 0.045), IL-6 (P = 0.050), and TNF-α (P = 0.020) increased linearly with number of days fed an HG diet. The correlation analysis revealed significant correlation between the colonic mucosal mRNA expression of cytokines and mucosal bacterial composition. Generally, HG feeding increased colonic fermentation and altered colonic mucosal bacterial communities, which eventually caused colonic mucosal damage and led to colonic dysfunction, and these changes occurred gradually over at least 4 weeks. PMID:29123511

Microbial fuel cells operating on mixed fatty acids.

PubMed

Freguia, Stefano; Teh, Ee Hoi; Boon, Nico; Leung, Kar Man; Keller, Jurg; Rabaey, Korneel

2010-02-01

Strategies are being developed to harvest the energy content of the wasted sludge generated from the treatment of domestic wastewater. Sludge can be hydrolysed and fermented, giving a mixture of volatile fatty acids (VFAs). Based on the composition of such a fermented stream, synthetic media were created and tested for VFA conversion in microbial fuel cells (MFCs). Mainly acetate and propionate were preferred as electron donors in the mixed VFA system, which generated a power density of 49+/-1 mW L(NAC)(-1). The other VFAs (butyrates/valerates/caproic acid) were also removed, albeit at lower rates. In single VFA tests, each VFA could be removed, but particularly i-butyrate did not provide significant current generation. PCR-DGGE indicated that the microbial community structure was highly determined by the fed VFA, rather than by the initial inoculum. The communities were dominated by Proteobacteria such as Geobacter, Comamonas, Pseudomonas and Pelobacter species. This study demonstrated the feasibility of using fatty acids, as present in fermented sludge hydrolysates, for current generation.

End product yields from the extraruminal fermentation of various polysaccharide, protein and nucleic acid components of biofuels feedstocks.

PubMed

Weimer, Paul J

2011-02-01

"Extraruminal" fermentations employing in vitro incubation of mixed ruminal bacterial consortia, are capable of converting a complex array of biomass materials to mixtures of volatile fatty acids (VFA), methane, and carbon dioxide. Most of the potential energy in the biomass feedstock is retained in the VFA products, which are potential reactants for electrochemical conversion to hydrocarbon fuels. Quantitative data on VFA yields and proportions from biomass components are necessary for determining industrial feasibility, but such measurements have not been systematically reported. VFA yields and proportions were determined for a variety of carbohydrates, proteins and nucleic acids. Carbohydrates yielded primarily acetic and propionic acids, while proteins also yielded a more favorable product mix (longer average chain length and branched chain VFAs). Addition of certain co-substrates (e.g., glycerol) favorably improved the VFA product mix. The results have implications for hydrocarbon fuel generation from biomass materials by hybrid fermentation/chemical processes. Published by Elsevier Ltd.

Establishment of ruminal enzyme activities and fermentation capacity in dairy calves from birth through weaning.

PubMed

Rey, M; Enjalbert, F; Monteils, V

2012-03-01

The objectives of this study were to characterize the establishment of ruminal fermentation and enzymatic activities in dairy calves from birth to weaning (d 83). Six Holstein calves, immediately separated from their mother at birth, were fed colostrum for 3 d after birth, and thereafter milk replacer, starter pelleted concentrate, and hay until d 83 of age. Ruminal samples were collected from each calf every day for the first 10 d, and additionally at d 12, 15, 19, 22, 26, 29, 33, 36, 40, 43, 47, 50, 55, 62, 69, and 83. Ruminal samples were collected 1h after milk feeding with a stomach tube. The pH and redox potential (E(h)) were immediately measured. Samples were kept for further determination of ammonia nitrogen (NH(3)-N) and volatile fatty acid (VFA) concentrations, and xylanase, amylase, urease, and protease activities. Ruminal pH averaged 6.69, 5.82, and 6.34, from d 1 to 9, d 10 to 40, and d 43 to 83 of age, respectively. At first day of life, the ruminal E(h) value was positive (+224 mV). From d 2 to 9, d 10 to 40, and d 43 to 83 of age, ruminal E(h) averaged -164, -115, and -141 mV, respectively. From d 1 to 3, d 4 to 22, and d 26 to 83 of age, NH(3)-N concentration averaged 60.1, 179.8, and 58.2 mg/L, respectively. No VFA were detected in ruminal samples collected on d 1 of life of calves. From d 2 to 10 and d 12 to 83 of age, ruminal total VFA concentration averaged 19.5 and 84.4mM, respectively. Neither ruminal xylanase or amylase activities were observed at d 1 of age. From d 5 to 15 and d 19 to 83 of age, the xylanase activity averaged 182.2 and 62.4 μmol of sugar released per hour per gram of ruminal content dry matter (DM), respectively. From d 5 to 83 of age, the amylase activity reached 35.4 μmol of sugar released per hour per gram of ruminal content DM. The ruminal ureolytic activity was observed with an average value of 6.9 μg of NH(3)-N released per minute per gram of ruminal content DM over the 83-d experimental period. From d 1 to 4 and d 5 to 83 of age, the proteolytic activity was 8.2 and 27.9 optical density units per hour per gram of ruminal content DM, respectively. The fermentative and enzymatic activities were rapidly established in the rumen from d 2 after birth. Most parameters did not evolve further after 1 mo of age. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Anaerobic Codigestion of Sludge: Addition of Butcher's Fat Waste as a Cosubstrate for Increasing Biogas Production.

PubMed

Martínez, E J; Gil, M V; Fernandez, C; Rosas, J G; Gómez, X

2016-01-01

Fat waste discarded from butcheries was used as a cosubstrate in the anaerobic codigestion of sewage sludge (SS). The process was evaluated under mesophilic and thermophilic conditions. The codigestion was successfully attained despite some inhibitory stages initially present that had their origin in the accumulation of volatile fatty acids (VFA) and adsorption of long-chain fatty acids (LCFA). The addition of a fat waste improved digestion stability and increased biogas yields thanks to the higher organic loading rate (OLR) applied to the reactors. However, thermophilic digestion was characterized by an effluent of poor quality and high VFA content. Results from spectroscopic analysis suggested the adsorption of lipid components onto the anaerobic biomass, thus disturbing the complete degradation of substrate during the treatment. The formation of fatty aggregates in the thermophilic reactor prevented process failure by avoiding the exposure of biomass to the toxic effect of high LCFA concentrations.

Fluorescence-based monitoring of tracer and substrate distribution in an UASB reactor.

PubMed

Lou, S J; Tartakovsky, B; Zeng, Y; Wu, P; Guiot, S R

2006-11-01

In this work, rhodamine-related fluorescence was measured on-line at four reactor heights in order to study hydrodynamics within an upflow anaerobic sludge bed reactor. A linear dependence of the dispersion coefficient (D) on the upflow velocity was observed, while the influence of the organic loading rate (OLR) was insignificant. Furthermore, the Bodenstein number of the reactor loaded with granulated sludge was found to be position-dependent with the largest values measured at the bottom of the sludge bed. This trend was not observed in the reactor without sludge. Chemical oxygen demand (COD) and volatile fatty acid (VFA) concentrations were measured at the same reactor heights as in rhodamine tests using conventional off-line analytical methods and on-line multiwavelength fluorometry. Significant spatial COD and VFA gradients were observed at organic loading rates above 6g COD l(R)(-1)d(-1) and linear upflow velocities below 0.8m h(-1).

Anaerobic Codigestion of Sludge: Addition of Butcher’s Fat Waste as a Cosubstrate for Increasing Biogas Production

PubMed Central

Martínez, E. J.; Gil, M. V.; Fernandez, C.; Rosas, J. G.

2016-01-01

Fat waste discarded from butcheries was used as a cosubstrate in the anaerobic codigestion of sewage sludge (SS). The process was evaluated under mesophilic and thermophilic conditions. The codigestion was successfully attained despite some inhibitory stages initially present that had their origin in the accumulation of volatile fatty acids (VFA) and adsorption of long-chain fatty acids (LCFA). The addition of a fat waste improved digestion stability and increased biogas yields thanks to the higher organic loading rate (OLR) applied to the reactors. However, thermophilic digestion was characterized by an effluent of poor quality and high VFA content. Results from spectroscopic analysis suggested the adsorption of lipid components onto the anaerobic biomass, thus disturbing the complete degradation of substrate during the treatment. The formation of fatty aggregates in the thermophilic reactor prevented process failure by avoiding the exposure of biomass to the toxic effect of high LCFA concentrations. PMID:27071074

New approach to control the methanogenic reactor of a two-phase anaerobic digestion system.

PubMed

von Sachs, Jürgen; Meyer, Ulrich; Rys, Paul; Feitkenhauer, Heiko

2003-03-01

A new control strategy for the methanogenic reactor of a two-phase anaerobic digestion system has been developed and successfully tested on the laboratory scale. The control strategy serves the purpose to detect inhibitory effects and to achieve good conversion. The concept is based on the idea that volatile fatty acids (VFA) can be measured in the influent of the methanogenic reactor by means of titration. Thus, information on the output (methane production) and input of the methanogenic reactor is available, and a (carbon) mass balance can be obtained. The control algorithm comprises a proportional/integral structure with the ratio of (a) the methane production rate measured online and (b) a maximum methane production rate expected (derived from the stoichiometry) as a control variable. The manipulated variable is the volumetric feed rate. Results are shown for an experiment with VFA (feed) concentration ramps and for experiments with sodium chloride as inhibitor.

Microbial examination of anaerobic sludge adaptation to animal slurry.

PubMed

Moset, V; Cerisuelo, A; Ferrer, P; Jimenez, A; Bertolini, E; Cambra-López, M

2014-01-01

The objective of this study was to evaluate changes in the microbial population of anaerobic sludge digesters during the adaptation to pig slurry (PS) using quantitative real-time polymerase chain reaction (qPCR) and qualitative scanning electron microscopy (SEM). Additionally, the relationship between microbial parameters and sludge physicochemical composition and methane yield was examined. Results showed that the addition of PS to an unadapted thermophilic anaerobic digester caused an increase in volatile fatty acids (VFA) concentration, a decrease in removal efficiency and CH4 yield. Additionally, increases in total bacteria and total archaea were observed using qPCR. Scanning electron micrographs provided a general overview of the sludge's cell morphology, morphological diversity and degree of organic matter degradation. A change in microbial morphotypes from homogeneous cell morphologies to a higher morphological diversity, similar to that observed in PS, was observed with the addition of PS by SEM. Therefore, the combination of qPCR and SEM allowed expanding the knowledge about the microbial adaptation to animal slurry in thermophilic anaerobic digesters.

Pre-digestion to enhance volatile fatty acids (VFAs) concentration as a carbon source for denitrification in treatment of liquid swine manure.

PubMed

Wu, Sarah Xiao; Chen, Lide; Zhu, Jun; Walquist, McKenzie; Christian, David

2018-04-30

Insufficient denitrification in biological treatment is often a result of the lack of a carbon source. In this study, use of the volatile fatty acids (VFAs) generated via pre-digestion as a carbon source to improve denitrification in sequencing batch reactor (SBR) treatment of liquid swine manure was investigated. The pre-digestion of swine manure was realized by storing the manure in a sealed container in room temperature and samples were taken periodically from the container to determine the VFA levels. The results showed that after 14 days of pre-digestion, the VFA level in the digested liquid was increased by 200%. A polynomial relationship for the VFA level in the digested manure with the digestion time was observed with a correlation coefficient being 0.9748. Two identical SBRs were built and operated on 8-h cycles in parallel, with one fed with pre-digested and the other raw swine manure. There were five phases included in each cycle, i.e., anaerobic (90 min), anoxic (150 min), anoxic/anaerobic (90 min), anoxic/aerobic (120 min), and settle/decant (30 min), and the feeding was split to 600 mL/200 mL and performed at the beginning of and 240 min into the cycle. The SBR fed on pre-digested swine manure achieved successful denitrification with only 0.35 mg/L nitrate left in the effluent, compared to 15.9 mg/L found in the effluent of the other SBR. Nitrite was not detected in the effluent from both SBRs. The results also indicated that there was no negative impact of feeding SBRs with the pre-digested liquid swine manure for treatment on the removal of other constituents such as total solids (TS), volatile solids (VS), suspended solids (SS), volatile suspended solids (VSS), and soluble chemical oxygen demand (COD). Therefore, anaerobic digestion as a pretreatment can be an effective way to condition liquid swine manure for SBR treatment to achieve sufficient nitrate removal.

A critical appraisal of vertebral fracture assessment in paediatrics.

PubMed

Kyriakou, Andreas; Shepherd, Sheila; Mason, Avril; Faisal Ahmed, S

2015-12-01

There is a need to improve our understanding of the clinical utility of vertebral fracture assessment (VFA) in paediatrics and this requires a thorough evaluation of its readability, reproducibility, and accuracy for identifying VF. VFA was performed independently by two observers, in 165 children and adolescents with a median age of 13.4 years (range, 3.6, 18). In 20 of these subjects, VFA was compared to lateral vertebral morphometry assessment on lateral spine X-ray (LVM). 1528 (84%) of the vertebrae were adequately visualised by both observers for VFA. Interobserver agreement in vertebral readability was 94% (kappa, 0.73 [95% CI, 0.68, 0.73]). 93% of the non-readable vertebrae were located between T6 and T9. Interobserver agreement per-vertebra for the presence of VF was 99% (kappa, 0.85 [95% CI, 0.79, 0.91]). Interobserver agreement per-subject was 91% (kappa, 0.78 [95% CI, 0.66, 0.87]). Per-vertebra agreement between LVM and VFA was 95% (kappa 0.79 [95% CI, 0.62, 0.92]) and per-subject agreement was 95% (kappa, 0.88 [95% CI, 0.58, 1.0]). Accepting LVM as the gold standard, VFA had a positive predictive value (PPV) of 90% and a negative predictive value (NPV) of 95% in per-vertebra analysis and a PPV of 100% and NPV of 93% in per-subject analysis. VFA reaches an excellent level of agreement between observers and a high level of accuracy in identifying VF in a paediatric population. The readability of vertebrae at the mid thoracic region is suboptimal and interpretation at this level should be exercised with caution. Copyright © 2015 Elsevier Inc. All rights reserved.

Elutriated acid fermentation of municipal primary sludge.

PubMed

Ahn, Young Ho; Speece, Richard E

2006-06-01

The performance of a novel fermentation process, adopting a sludge blanket type configuration, for higher hydrolysis/acidogenesis of the municipal primary sludge was investigated under batch and semi-continuous conditions with varying pH and temperature. This acid elutriation slurry reactor provided higher system performance with a short HRT (5d) and higher acidogenic effluent quality under pH 9 and thermophilic (55 degrees C) conditions. The hydrolysis of the sludge was revealed to be significantly dependent on seasonal effects for sludge characteristics but with little impact on acidogenesis. Based on the rainy season at the optimal conditions, VFA production and recovery fraction (VFA(COD)/COD) were 0.18 g VFA(COD)/g VSS(COD) and 63%. As byproducts, nitrogen and phosphorus release were measured at 0.006 g N/g VSS(COD) and 0.003 g P/g VSS(COD), respectively. For the mass balance in a full-scale plant (Q=158,880 m(3)/d) based on the rainy season, the VFA and non-VFA (as COD) production were 3110 kg VFA(COD)/d and 1800 kg COD/d, resulting in an increase of organics of 31 mg COD/L and 20mg VFA(COD)/L and nutrients of 0.7 mg N/L and 0.3 mg P/L in the influent sewage. The economical benefit from this process application was estimated to be about 67 dollars per 1000 m(3) of sewage except for energy requirements and also, better benefits can be expected during the dry season. Moreover, the results revealed that the process has various additional advantages such as pathogen-free stabilized solids production, excellent solids control and economical benefits.

Empirical prediction of net portal appearance of volatile fatty acids, glucose, and their secondary metabolites (beta-hydroxybutyrate, lactate) from dietary characteristics in ruminants: A meta-analysis approach.

PubMed

Loncke, C; Ortigues-Marty, I; Vernet, J; Lapierre, H; Sauvant, D; Nozière, P

2009-01-01

The current trend in energy feeding systems for ruminants toward a nutrient-based system requires dietary energy supply to be determined in terms of amount and nature of absorbed energy-yielding nutrients. The objective of this study was to establish response equations on the net portal appearance (NPA) of VFA and glucose, and their secondary metabolites beta-hydroxybutyrate (BHBA) and lactate, to changes in intake level and chemical dietary characteristics based on the Institut National de la Recherche Agronomique Feed Evaluation System for Ruminants. Meta-analyses were applied on published data compiled from the FLORA database, which pools the results on net splanchnic nutrient fluxes in multi-catheterized ruminants from international publications. For each nutrient, several prediction variables were tested. We obtained robust models for intakes up to 30 g of DM x d(-1) x kg of BW(-1) and diets containing less than 70 g of concentrate per 100 g of DM. These models were designed to predict the NPA (mmol x h(-1) x kg of BW(-1)) of total VFA based on the amount of ruminally fermented OM (RfOM) intake [adjusted R(2) (R(2)(adj)) = 0.95; residual means square errors (RMSE) = 0.24], to predict VFA profile (mol/100 mol of total VFA) based on type of RfOM intake (acetate: R(2)(adj) = 0.85, RMSE = 2.2; propionate: R(2)(adj) = 0.76, RMSE = 2.2; butyrate: R(2)(adj) = 0.76, RMSE = 1.09), and to predict the NPA (mmol x h(-1) x kg of BW(-1)) of glucose based on the starch digested in the small intestine independent of ruminant species, and while presenting no interfering factors on the residuals and individual slopes. The model predicting the NPA (mmol x h(-1) x kg of BW(-1)) of BHBA based on the amount of RfOM intake (R(2)(adj) = 0.91; RMSE = 0.036) was species-dependent, and the model predicting NPA (mmol x h(-1) x kg of BW(-1)) of lactate based on starch digested in the rumen (R(2)(adj) = 0.77; RMSE = 0.042) presented a wide dispersion. However, the NPA (mmol x h(-1) x kg of BW(-1)) of BHBA was related to the NPA of both butyrate (R(2)(adj) = 0.85; RMSE = 0.054) and acetate (R(2)(adj) = 0.85; RMSE = 0.052), and the NPA (mmol x h(-1) x kg of BW (-1)) of lactate was related to the NPA of propionate (R(2)(adj) = 0.51; RMSE = 0.096). This research showed that it is possible to accurately predict the amount and nature of absorbed nutrient fluxes based on dietary characteristics in both sheep and cattle. This work aims to quantify the consequences of digestion and portal-drained viscera metabolism on nutrient availability. These results can provide deeper insight into biological processes and help develop improved tools for dietary formulation.

Production of volatile fatty acids from sewage organic matter by combined bioflocculation and alkaline fermentation.

PubMed

Khiewwijit, Rungnapha; Temmink, Hardy; Labanda, Alvaro; Rijnaarts, Huub; Keesman, Karel J

2015-12-01

This study explored the potential of volatile fatty acids (VFA) production from sewage by a combined high-loaded membrane bioreactor and sequencing batch fermenter. VFA production was optimized with respect to SRT and alkaline pH (pH 8-10). Application of pH shock to a value of 9 at the start of a sequencing batch cycle, followed by a pH uncontrolled phase for 7days, gave the highest VFA yield of 440mgVFA-COD/g VSS. This yield was much higher than at fermentation without pH control or at a constant pH between 8 and 10. The high yield in the pH 9 shocked system could be explained by (1) a reduction of methanogenic activity, or (2) a high degree of solids degradation or (3) an enhanced protein hydrolysis and fermentation. VFA production can be further optimized by fine-tuning pH level and longer operation, possibly allowing enrichment of alkalophilic and alkali-tolerant fermenting microorganisms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anaerobic degradation of coconut husk leachate using UASB-reactor.

PubMed

Neena, C; Ambily, P S; Jisha, M S

2007-07-01

Reffing of coconut husk, the majorprocess in quality coir fibre extraction, causes serious pollution with brackish water lagoons of Kerala. An attempt is made to treat the coconut husk leachate by using a laboratory scale UASB-reactor The experiment was conducted with loading of leachate from 1 kg of fresh coconut husk. The anaerobic treatment was done continuously The parameters like VFA, pH, COD and polyphenols were analysed regularly during the evaluation of the reactor performance. The polyphenol, VFA and COD were diminished gradually with time. The pH of the reactor during the study was found to be in the range of 6-8. The biogas production was increased with loading and about 82% of the total COD/kg husk could be converted to biogas. The maximum polyphenol loading in the reactor was reached to about 298.51 mg/l of husk.

Correlation between composition of the bacterial community and concentration of volatile fatty acids in the rumen during the transition period and ketosis in dairy cows.

PubMed

Wang, Xiaoxu; Li, Xiaobing; Zhao, Chenxu; Hu, Pan; Chen, Hui; Liu, Zhaoxi; Liu, Guowen; Wang, Zhe

2012-04-01

The transition period is a severe challenge to dairy cows. Glucose supply cannot meet demand and body fat is mobilized, potentially leading to negative energy balance (NEB), ketosis, or fatty liver. Propionate produces glucose by gluconeogenesis, which depends heavily on the number and species of microbes. In the present study, we analyzed the rumen microbiome composition of cows in the transition period, cows with ketosis, and nonperinatal cows by terminal restriction fragment length polymorphism (TRFLP) analysis of 16S rRNA genes and quantitative PCR. TRFLP analysis indicated that the quantity of Veillonellaceae organisms was reduced and that of Streptococcaceae organisms was increased in rumen samples from the transition period and ketosis groups, with the number of Lactobacillaceae organisms increased after calving. Quantitative PCR data suggested that the numbers of the main propionate-producing microbes, Megasphaera elsdenii and Selenomonas ruminantium, were decreased, while numbers of the main lactate-producing bacterium, Streptococcus bovis, were increased in the rumen of cows from the transition period and ketosis groups, with the number of Lactobacillus sp. organisms increased after calving. Volatile fatty acid (VFA) and glucose concentrations were decreased, but the lactic acid concentration was increased, in rumen samples from the transition period and ketosis groups. Our results indicate that the VFA concentration is significantly related to the numbers of Selenomonas ruminantium and Megasphaera elsdenii organisms in the rumen.

Correlation between Composition of the Bacterial Community and Concentration of Volatile Fatty Acids in the Rumen during the Transition Period and Ketosis in Dairy Cows

PubMed Central

Wang, Xiaoxu; Li, Xiaobing; Zhao, Chenxu; Hu, Pan; Chen, Hui; Liu, Zhaoxi

2012-01-01

The transition period is a severe challenge to dairy cows. Glucose supply cannot meet demand and body fat is mobilized, potentially leading to negative energy balance (NEB), ketosis, or fatty liver. Propionate produces glucose by gluconeogenesis, which depends heavily on the number and species of microbes. In the present study, we analyzed the rumen microbiome composition of cows in the transition period, cows with ketosis, and nonperinatal cows by terminal restriction fragment length polymorphism (TRFLP) analysis of 16S rRNA genes and quantitative PCR. TRFLP analysis indicated that the quantity of Veillonellaceae organisms was reduced and that of Streptococcaceae organisms was increased in rumen samples from the transition period and ketosis groups, with the number of Lactobacillaceae organisms increased after calving. Quantitative PCR data suggested that the numbers of the main propionate-producing microbes, Megasphaera elsdenii and Selenomonas ruminantium, were decreased, while numbers of the main lactate-producing bacterium, Streptococcus bovis, were increased in the rumen of cows from the transition period and ketosis groups, with the number of Lactobacillus sp. organisms increased after calving. Volatile fatty acid (VFA) and glucose concentrations were decreased, but the lactic acid concentration was increased, in rumen samples from the transition period and ketosis groups. Our results indicate that the VFA concentration is significantly related to the numbers of Selenomonas ruminantium and Megasphaera elsdenii organisms in the rumen. PMID:22267666

In vitro fermentation characteristics of diets with different forage/concentrate ratios: comparison of rumen and faecal inocula.

PubMed

Zicarelli, Fabio; Calabrò, Serena; Cutrignelli, Monica I; Infascelli, Federico; Tudisco, Raffaella; Bovera, Fulvia; Piccolo, Vincenzo

2011-05-01

The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso-protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep. Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (R(max) ) increased as the amount of concentrate in the diet increased. R(max) was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, R(max) increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased. The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique. Copyright © 2011 Society of Chemical Industry.

In vitro fermentation characteristics of two mushroom species, an herb, and their polysaccharide fractions, using chicken cecal contents as inoculum.

PubMed

Guo, F C; Williams, B A; Kwakkel, R P; Verstegen, M W A

2003-10-01

In vitro fermentabilities of two mushrooms (Lentinus edodes--LenS; Tremella fuciformis--TreS), an herb (Astragalus membranaceus--AstS), and their polysaccharide fractions (LenE, TreE, and AstE) were investigated using microflora from chicken ceca. Polysaccharides were extracted using the hot water method. The mushrooms had lower polysaccharide yields (8 to 10%) than the herb (31%). Fermentation kinetics were determined using the in vitro cumulative gas production technique. End-products, such as gas, volatile fatty acids (VFA), and ammonia, were also determined. The gas profiles of intact materials were similar for AstS and LenS. The TreS had a diphasic digestion pattern. The extracts had similar profiles to the intact materials though gas production rates were faster. Intact materials tended to produce less VFA than the extracts though LenS and AstE had the highest total VFA production overall. Intact materials contained more protein than the extracts, and therefore resulted in more branched-chain fatty acids and ammonia. Fermentation kinetics and end-point products demonstrated differences in availability of substrates between the mushrooms and herb. These medicinal mushroom and herb materials, particularly their polysaccharide extracts, show promise in altering microbial activities and composition in chicken ceca. In vivo experiments are necessary for confirmation of this hypothesis.

The particulate passage rate, nutrient composition and fermentation characteristics across gastrointestinal tracts in lactating dairy cows fed three different forage source diets.

PubMed

Wang, B; Gu, F F; Huang, X B; Liu, J X

2018-04-19

This study was conducted to investigate the particulate passage rate, nutrient characteristics and fermentation parameters across the gastrointestinal tract (GIT) in lactating dairy cows fed cereal straws in comparison with alfalfa hay. Eighteen multiparous Holstein cows were randomly assigned to one of three experimental diets consisting of 55% concentrate, 15% corn silage and 30% different forage sources as follows (% of dry matter [DM]): (i) 23% alfalfa hay and 7% Chinese wild rye hay (AH); (ii) 30% corn stover (CS); and (iii) 30% rice straw (RS). The Cr-mordanted corn silage-neutral detergent fibre was used to estimate the passage flow at week 14. After 14-week feeding, the animals were slaughtered to collect the gastrointestinal digesta. Dietary forage sources had little effect on the fractional passage rates in the rumen (range from 5.05 to 6.25%/hr) or hindgut (range from 4.49 to 5.24%/hr). Total volatile fatty acid (VFA) concentration in the caecum was highest, followed by the rumen, colon and rectum, and the lowest in the abomasum and duodenum, indicating that the large intestines, especially caecum, are the important positions for carbohydrate degradation. Greater proportion of propionate and butyrate and lower acetate were found in the AH compared to CS or RS in colon, but higher acetate in abomasum was found in the cows fed CS or RS compared to AH. In conclusion, cereal straw diets did not change the particulate passage rate in the rumen and hindgut which might be mainly due to the similar DM intake among these three diets. Different forage source diets significantly changed VFA proportion in the abomasum and colon, indicating the existence of different digestion or absorption rates in these tracts among the experimental diets. © 2018 Blackwell Verlag GmbH.

[Studies on anaerobic infection in oro-maxillary region--rapid diagnosis by gas-liquid chromatography and antibiotic susceptibilities of anaerobic bacteria].

PubMed

Tanaka, J I

1989-08-01

Subject material for this study was pus collected from patients with purulent inflammation in the oro-maxillary region. Direct gas-liquid chromatography (GLC) analysis was made, bacterial isolation and identification were carried out, and comparisons were made with results from GLC analysis and anaerobic isolates in a PYG medium. In addition, antibiotic susceptibilities of anaerobic bacteria were examined. Results 1. Anaerobic bacteria were isolated from 85 of 100 cases of obstructive abscesses. Of the 85, 49 were cases of mixed infection involving both anaerobic and aerobic bacteria; and 64 cases were involved with more than 2 species of anaerobic bacteria. Of the 184 strains of anaerobic isolates, 53 were Bacteroides sp. and 51 were Peptostreptococcus sp. The 2 groups accounted for more than half of the isolates. 2. Group A, in which no VFA was detected, accounted for 17 out of 100 cases. Group B, in which acetic acid was detected, accounted for 20 cases; and Group C, in which butyric acid was detected, accounted for 20 cases; and Group D, in which iso-valeric acid was detected, accounted for 8 cases. Direct GLC analysis revealed iso-caproic and caproic acids in the 35 cases constituting Group E. 3. Whereas the percentage of anaerobic bacteria was 64.7% in Group A and 60% in Group B, significantly higher percentages were noted in Group C (95%), Group D (100%) and Group E (100%). The following species were isolated as major member in the groups; Group A--Streptococcus intermedius, Group B--Peptostreptococcus micros, Group C--Fusobacterium nucleatum, Group D--Bacteroides gingivalis, and Group E--Peptostreptococcus anaerobius. 4. In all cases, the sum of VFA produced in the PYG medium by anaerobic isolates was classified into Group A' to E'. Ratios of agreement between VFA as revealed by direct GLC and VFA as revealed by PYG.GLC were as follows: Group A-A'; 47.1%, Group B-B' and C-C'; 45%, Group D-D'; 87.5%, and Group E-E'; 62.9%. 5. In Group B, no propionic acid was detected. The 2 cases in which acetic acid occurred in a concentration greater than 14 x 10(-4) meq/ml belonged to Group B'. In Group C, no isobutyric acid was detected; and the 5 cases in which butyric acid was detected in a concentration of more than 7 x 10(-4) meq/ml belonged to Group C'. Varelic acid was not detected in Group D; and 7 out of the 8 cases in which iso-valeric acid, irrespective of concentration, was detected belonged to Group D'.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of pH control and 'hydraulic flush' on hydrolysis and Volatile Fatty Acids (VFA) production and profile in anaerobic leach bed reactors digesting a high solids content substrate.

PubMed

Cysneiros, Denise; Banks, Charles J; Heaven, Sonia; Karatzas, Kimon-Andreas G

2012-11-01

The effect of hydraulic flush and pH control on hydrolysis, Volatile Fatty Acids (VFA) production and profile in anaerobic leach bed reactors was investigated for the first time. Six reactors were operated under different regimes for two consecutive batches of 28days each. Buffering at pH ∼6.5 improved hydrolysis (Volatile Solid (VS) degradation) and VFA production by ∼50%. Butyric and acetic acid were dominant when reactors were buffered, while only butyric acid was produced at low pH. Hydraulic flush enhanced VS degradation and VFA production by ∼15% and ∼32%, respectively. Most Probable Number (MPN) of cellulolytic microorganisms indicated a wash out when hydraulic flush was applied, but pH control helped to counteract this. The highest VS degradation (∼89%), VFA yield (0.84kgCODkg(-1)VS(added)) and theoretical methane potential (0.37m(3)CH(4)kg(-1)VS(added)) were obtained when pH control and hydraulic flush were applied, and therefore, these conditions are recommended. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of feeding salt-tolerant forage cultivated in saline-alkaline land on rumen fermentation, feed digestibility and nitrogen balance in lamb.

PubMed

Wang, Cong; Dong, Kuan Hu; Liu, Qiang; Yang, Wen Zhu; Zhao, Xiang; Liu, Sheng Qiang; He, Ting Ting; Liu, Zhuang Yu

2011-05-01

Mixing salt-tolerant plants with other plants may affect rumen fermentation, which could result in an increase of feed conversion rate. The objective of this study was to evaluate the effects of partially or entirely replacing the corn stover with a mixture of salt-tolerant forage (Dahurian wildrye grass, weeping alkaligrass and erect milkvetch) in the diet of lambs on ruminal fermentation, feed digestibility and nitrogen (N) balance. Ratios of corn stover to the mixture of salt-tolerant forages in the four experimental diets were 100:0, 67:33, 33:67 and 0:100, respectively, for control, low (LF), medium (MF) and high (HF). Ruminal pH was lower (P = 0.048) with LF and MF than with control and HF diets. Total VFA concentration was consistently higher (P = 0.039) for LF and MF than for control and HF with increasing amount of salt-tolerant forage. Ratio of acetate to propionate was linearly (P = 0.019) decreased due to the decrease in acetate production. Digestibilities of OM, NDF and CP in the whole tract linearly (P < 0.002) decreased with increasing amount of salt-tolerant forage. Similarly, retained N and ratio of retained N to digestible N also linearly (P < 0.005) decreased. Feeding salt-tolerant forage cultivated in saline-alkaline land improved rumen fermentation with increased total VFA production, and changed the rumen fermentation pattern to increased butyrate production. However, the decreased feed digestibility in the whole digestive tract of lamb may reduce nutrient availability to animals and thus adversely affect animal productivity. Additionally, feeding salt-tolerant forages may require more protein supplement to meet animal requirements, because of the low protein content and low protein digestibility of the salt-tolerant forages. Copyright © 2011 Society of Chemical Industry.

Edible Oil Barriers for Treatment of Chlorinated Solvent Contaminated Groundwater

DTIC Science & Technology

2009-07-01

CF Chloroform Cl# Chlorine Number CO Carbon Monoxide CT Carbon Tetrachloride CVOC Chlorinated Volatile Organic Compound 1,2-DCA 1,2...As Safe HCl Hydrochloric Acid HRC® Hydrogen Release Compound IDW Investigation-Derived Waste ISCO In Situ Chemical Oxidation LEL Lower...Total Organic Carbon VC Vinyl Chloride VFA Volatile Fatty Acid VOC Volatile Organic Compound ZVI Zero Valent Iron viii ACKNOWLEDGEMENTS

Comparative Analysis of Performance and Microbial Characteristics Between High-Solid and Low-Solid Anaerobic Digestion of Sewage Sludge Under Mesophilic Conditions.

PubMed

Lu, Qin; Yi, Jing; Yang, Dianhai

2016-01-01

High-solid anaerobic digestion of sewage sludge achieves highly efficient volatile solid reduction, and production of volatile fatty acid (VFA) and methane compared with conventional low-solid anaerobic digestion. In this study, the potential mechanisms of the better performance in high-solid anaerobic digestion of sewage sludge were investigated by using 454 high-throughput pyrosequencing and real-time PCR to analyze the microbial characteristics in sewage sludge fermentation reactors. The results obtained by 454 high-throughput pyrosequencing revealed that the phyla Chloroflexi, Bacteroidetes, and Firmicutes were the dominant functional microorganisms in high-solid and low-solid anaerobic systems. Meanwhile, the real-time PCR assays showed that high-solid anaerobic digestion significantly increased the number of total bacteria, which enhanced the hydrolysis and acidification of sewage sludge. Further study indicated that the number of total archaea (dominated by Methanosarcina) in a high-solid anaerobic fermentation reactor was also higher than that in a low-solid reactor, resulting in higher VFA consumption and methane production. Hence, the increased key bacteria and methanogenic archaea involved in sewage sludge hydrolysis, acidification, and methanogenesis resulted in the better performance of high-solid anaerobic sewage sludge fermentation.

Visceral fat area is a strong predictor of leukocyte cell-derived chemotaxin 2, a potential biomarker of dyslipidemia.

PubMed

Tanisawa, Kumpei; Taniguchi, Hirokazu; Sun, Xiaomin; Ito, Tomoko; Kawakami, Ryoko; Sakamoto, Shizuo; Higuchi, Mitsuru

2017-01-01

Leukocyte cell-derived chemotaxin 2 (LECT2) is a hepatokine linking obesity to skeletal muscle insulin resistance. Although previous studies reported that obesity was associated with high levels of circulating LECT2 in human, the associations of detailed body fat distribution with LECT2 levels have not been examined. Furthermore, although animal study suggested that exercise decreased circulating LECT2 levels, it remains unknown whether physical fitness is associated with LECT2 levels in human. We therefore examined the relationship of plasma LECT2 levels with various adiposity indices and cardiorespiratory fitness (CRF) in middle-aged and elderly Japanese men. Furthermore, we examined the relationship of LECT2 levels with the presence of metabolic syndrome, hypertension, insulin resistance and dyslipidemia to determine the clinical significance of measuring circulating LECT2. This was a cross-sectional study of 143 Japanese men (age: 30-79 years). Participants' plasma LECT2 levels were measured by an enzyme-linked immunosorbent assay. To assess their abdominal fat distributions, visceral fat area (VFA) and subcutaneous fat area (SFA) were measured using magnetic resonance imaging. CRF was assessed by measuring peak oxygen uptake ([Formula: see text]). All adiposity indices measured in this study were positively correlated with plasma LECT2 levels, while [Formula: see text] was negatively correlated with LECT2 levels after adjustment for age. The correlations, except for VFA were no longer significant with further adjustment for VFA. Stepwise multiple linear regression analysis revealed that VFA was the strongest predictor of plasma LECT2 levels. Plasma LECT2 levels differed based on the presence of metabolic syndrome and dyslipidemia, but not hypertension and insulin resistance. Logistic regression analyses revealed that plasma LECT2 levels were significantly associated with dyslipidemia independently of VFA; VFA was not significantly associated with dyslipidemia after adjustment for LECT2. VFA was the strongest predictor of plasma LECT2 that is a potential biomarker linking visceral obesity to dyslipidemia.

Substitution of wheat dried distillers grains with solubles for barley grain or barley silage in feedlot cattle diets: intake, digestibility, and ruminal fermentation.

PubMed

Li, Y L; McAllister, T A; Beauchemin, K A; He, M L; McKinnon, J J; Yang, W Z

2011-08-01

The objective of this study was to evaluate the effects of substituting wheat dried distillers grains with solubles (DDGS) for barley grain and barley silage on intake, digestibility, and ruminal fermentation in feedlot beef cattle. Eight ruminally cannulated Angus heifers (initial BW 455 ± 10.8 kg) were assigned to a replicated 4 × 4 Latin square design with 4 treatments: control, low (25%), medium (30%), and high (35%) wheat DDGS (DM basis). The diets consisted of barley silage, barley concentrate, and wheat DDGS in ratios of 15:85:0 (CON), 10:65:25 (25DDGS), 5:65:30 (30DDGS), and 0:65:35 (35DDGS; DM basis), respectively. The diets were formulated such that wheat DDGS was substituted for both barley grain and barley silage to evaluate whether wheat DDGS can be fed as a source of both energy (grain) and fiber in feedlot finishing diets. Intakes (kg/d) of DM and OM were not different, whereas those of CP, NDF, ADF, and ether extract (EE) were greater (P < 0.01) and intake of starch was less (P < 0.01) for the 25DDGS compared with the CON diet. The digestibilities of CP, NDF, ADF, and EE in the total digestive tract were greater (P < 0.05) for 25DDGS vs. CON. Ruminal pH and total VFA concentrations were not different (P > 0.15) between 25DDGS and CON diets. Replacing barley silage with increasing amounts of wheat DDGS (i.e., from 25DDGS to 35DDGS) linearly reduced (P < 0.05) intakes of DM and other nutrients without altering (P=0.40) CP intake. In contrast, digestibilities of DM and other nutrients in the total digestive tract linearly increased (P < 0.05) with increasing wheat DDGS except for that of EE. Additionally, with increasing amounts of wheat DDGS, mean ruminal pH tended (P=0.10) to linearly decrease, and ruminal pH status decreased with longer (P=0.04) duration of pH <5.5 and <5.2, and greater (P=0.01) curve area under pH <5.8 and <5.5 without altering (P > 0.19) ruminal VFA and NH(3)-N concentrations. Results indicated that wheat DDGS can be effectively used to replace both barley grain and silage at a moderate amount to meet energy and fiber requirements of finishing cattle. However, when silage content of the diet is low (<10%), wheat DDGS is not an effective fiber source, so replacing forage fiber with wheat DDGS in finishing diets decreases overall ruminal pH status even though the rapidly fermentable starch content of the diet is considerably reduced. © 2011 American Society of Animal Science. All rights reserved.

Effects of dietary changes and yeast culture (Saccharomyces cerevisiae) on rumen microbial fermentation of Holstein heifers.

PubMed

Moya, D; Calsamiglia, S; Ferret, A; Blanch, M; Fandiño, J I; Castillejos, L; Yoon, I

2009-09-01

The effects of a dietary challenge to induce digestive upsets and supplementation with yeast culture on rumen microbial fermentation were studied using 12 Holstein heifers (277 +/- 28 kg of BW) fitted with a ruminal cannula, in a crossover design with 2 periods of 5 wk. In each period, after 3 wk of adaptation to a 100% forage diet, the dietary challenge consisted of increasing the amount of grain at a rate of 2.5 kg/d (as-fed basis) over a period of 4 d, until a 10:90 forage:concentrate diet was reached, and then it was maintained for 10 d. Between periods, animals were fed again the 100% forage diet without any treatment for 1 wk as a wash-out period. Treatments started the first day of each period, and they were a control diet (CL) or the same diet with addition of yeast culture (YC, Diamond V XPCLS). Digestive upsets were determined by visual observation of bloat or by a reduction in feed intake (as-fed basis) of 50% or more compared with intake on the previous day. Feed intake was determined daily at 24-h intervals during the adaptation period and daily at 2, 6, and 12 h postfeeding during the dietary challenge. Ruminal liquid samples were collected daily during the dietary challenge to determine ruminal pH at 0, 3, 6, and 12 h postfeeding, and total and individual VFA, lactic acid, ammonia-N, and rumen fluid viscosity at 0 and 6 h postfeeding. The 16s rRNA gene copies of Streptococcus bovis and Megasphaera elsdenii were determined by quantitative PCR. Foam height and strength of the rumen fluid were also determined the day after the digestive upset to evaluate potential foam production. A total of 20 cases (83.3%) of digestive upsets were recorded in both periods during the dietary challenge, all diagnosed due to a reduction in feed intake. Rumen fermentation profile at 0 h on the digestive upset day was characterized by low ruminal pH, which remained under 6.0 for 18 h, accompanied by elevated total VFA concentration and, in some cases, by elevated lactate concentration. Addition of YC during the dietary challenge did not affect the incidence (10 cases per treatment) or time (7.00 +/- 0.62 d) to digestive upset. However, YC reduced (P < 0.05) the foam strength on the day after digestive upset, suggesting potential benefits of reducing the risk of developing bloat. The proposed dietary challenge model was successful in causing a digestive upset as indicated by reduced feed intake, but the YC addition had no significant impact on rumen fermentation.

Influence of Wheat Straw Pelletizing and Inclusion Rate in Dry Rolled or Steam-flaked Corn-based Finishing Diets on Characteristics of Digestion for Feedlot Cattle.

PubMed

Manríquez, O M; Montano, M F; Calderon, J F; Valdez, J A; Chirino, J O; Gonzalez, V M; Salinas-Chavira, J; Mendoza, G D; Soto, S; Zinn, R A

2016-06-01

Eight Holstein steers (216±48 kg body weight) fitted with ruminal and duodenal cannulas were used to evaluate effects of wheat straw processing (ground vs pelleted) at two straw inclusion rates (7% and 14%; dry matter basis) in dry rolled or steam-flaked corn-based finishing diets on characteristics of digestion. The experimental design was a split plot consisting of two simultaneous 4×4 Latin squares. Increasing straw level reduced ruminal (p<0.01) and total tract (p = 0.03) organic matter (OM) digestion. As expected, increasing wheat straw level from 7% to 14% decreased (p<0.05) ruminal and total tract digestion of OM. Digestion of neutral detergent fiber (NDF) and starch, per se, were not affected (p>0.10) by wheat straw level. Likewise, straw level did not influence ruminal acetate and propionate molar proportions or estimated methane production (p>0.10). Pelleting straw did not affect (p≥0.48) ruminal digestion of OM, NDF, and starch, or microbial efficiency. Ruminal feed N digestion was greater (7.4%; p = 0.02) for ground than for pelleted wheat straw diets. Although ruminal starch digestion was not affected by straw processing, post-ruminal (p<0.01), and total-tract starch (p = 0.05) digestion were greater for ground than for pelleted wheat straw diets, resulting in a tendency for increased post-ruminal (p = 0.06) and total tract (p = 0.07) OM digestion. Pelleting wheat straw decreased (p<0.01) ruminal pH, although ruminal volatile fatty acids (VFA) concentration and estimated methane were not affected (p≥0.27). Ruminal digestion of OM and starch, and post-ruminal and total tract digestion of OM, starch and N were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal NDF digestion was greater (p = 0.02) for dry rolled than for steam-flaked corn, although total tract NDF digestion was unaffected (p = 0.94). Ruminal microbial efficiency and ruminal degradation of feed N were not affected (p>0.14) by corn processing. However, microbial N flow to the small intestine and ruminal N efficiency (non-ammonia N flow to the small intestine/N intake) were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal pH and total VFA concentration were not affected (p≥ 0.16) by corn processing method. Compared with dry rolled corn, steam-flaked corn-based diets resulted in decreased acetate:propionate molar ratio (p = 0.02). It is concluded that at 7% or 14% straw inclusion rate, changes in physical characteristics of wheat straw brought about by pelleting negatively impact OM digestion of both steam-flaked and dry-rolled corn-based finishing diets. This effect is due to decreased post-ruminal starch digestion. Replacement of ground straw with pelleted straw also may decrease ruminal pH.

Effects of trace element addition on process stability during anaerobic co-digestion of OFMSW and slaughterhouse waste.

PubMed

Moestedt, J; Nordell, E; Shakeri Yekta, S; Lundgren, J; Martí, M; Sundberg, C; Ejlertsson, J; Svensson, B H; Björn, A

2016-01-01

This study used semi-continuous laboratory scale biogas reactors to simulate the effects of trace-element addition in different combinations, while degrading the organic fraction of municipal solid waste and slaughterhouse waste. The results show that the combined addition of Fe, Co and Ni was superior to the addition of only Fe, Fe and Co or Fe and Ni. However, the addition of only Fe resulted in a more stable process than the combined addition of Fe and Co, perhaps indicating a too efficient acidogenesis and/or homoacetogenesis in relation to a Ni-deprived methanogenic population. The results were observed in terms of higher biogas production (+9%), biogas production rates (+35%) and reduced VFA concentration for combined addition compared to only Fe and Ni. The higher stability was supported by observations of differences in viscosity, intraday VFA- and biogas kinetics as well as by the 16S rRNA gene and 16S rRNA of the methanogens. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of covering composting piles with mature compost on ammonia emission and microbial community structure of composting process.

PubMed

Maeda, Koki; Morioka, Riki; Osada, Takashi

2009-01-01

To control ammonia (NH(3)) volatilization from the dairy cattle (Bos taurus) manure composting process, a compost pile was covered with mature compost and the gas emissions evaluated using the dynamic chamber system. The peak of NH(3) volatilization observed immediately after piling up of the compost was reduced from 196 to 62 mg/m(3) by covering the compost pile with mature compost. The accumulation of NH(4)-N to the covered mature compost was also observed. Covering and mixing the compost with mature compost had no effect on the microbial community structure. However, over time the microbial community structure changed because of a decrease in easily degradable organic compounds in the compost piles. The availability of volatile fatty acids (VFA) was considered to be important for microbial community structure in the compost. After the VFA had disappeared, the NO(3)-N concentration increased and the cellulose degrading bacteria such as Cytophaga increased in number.

Leachate flush strategies for managing volatile fatty acids accumulation in leach-bed reactors.

PubMed

Riggio, S; Torrijos, M; Vives, G; Esposito, G; van Hullebusch, E D; Steyer, J P; Escudié, R

2017-05-01

In anaerobic leach-bed reactors (LBRs) co-digesting an easily- and a slowly-degradable substrate, the importance of the leachate flush both on extracting volatile fatty acids (VFAs) at the beginning of newly-started batches and on their consumption in mature reactors was tested. Regarding VFA extraction three leachate flush-rate conditions were studied: 0.5, 1 and 2Lkg -1 TSd -1 . Results showed that increasing the leachate flush-rate during the acidification phase is essential to increase degradation kinetics. After this initial phase, leachate injection is less important and the flush-rate could be reduced. The injection in mature reactors of leachate with an acetic acid concentration of 5 or 10gL -1 showed that for an optimized VFA consumption in LBRs, VFAs should be provided straight after the methane production peak in order to profit from a higher methanogenic activity, and every 6-7h to maintain a high biogas production rate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of substrate and cation requirement on anaerobic volatile fatty acid conversion rates at elevated biogas pressure.

PubMed

Lindeboom, Ralph E F; Ferrer, Ivet; Weijma, Jan; van Lier, Jules B

2013-12-01

This work studied the anaerobic conversion of neutralized volatile fatty acids (VFA) into biogas under Autogenerative High Pressure Digestion (AHPD) conditions. The effects of the operating conditions on the biogas quality, and the substrate utilisation rates were evaluated using 3 AHPD reactors (0.6 L); feeding a concentration of acetate and VFA (1-10 g COD/L) corresponding to an expected pressure increase of 1-20 bar. The biogas composition improved with pressure up to 4.5 bar (>93% CH4), and stabilized at 10 and 20 bar. Both, acetotrophic and hydrogenotrophic methanogenic activity was observed. Substrate utilisation rates of 0.2, 0.1 and 0.1 g CODCH4/g VSS/d for acetate, propionate and butyrate were found to decrease by up to 50% with increasing final pressure. Most likely increased Na(+)-requirement to achieve CO2 sequestration at higher pressure rather than end-product inhibition was responsible. Copyright © 2013 Elsevier Ltd. All rights reserved.

Anaerobic digestion characteristics of pig manures depending on various growth stages and initial substrate concentrations in a scaled pig farm in Southern China.

PubMed

Zhang, Wanqin; Lang, Qianqian; Wu, Shubiao; Li, Wei; Bah, Hamidou; Dong, Renjie

2014-03-01

The characteristics of anaerobic digestion of pig manure from different growth stages were investigated. According to growth stage, batch experiments were performed using gestating sow manure (GSM), swine nursery with post-weaned piglet manure (SNM), growing fattening manure (GFM) and mixed manure (MM) as substrates at four substrate concentrations (40, 50, 65 and 80gVS/L) under mesophilic conditions. The maximum methane yields of MM, SNM, GSM and GFM were 354.7, 328.7, 282.4 and 263.5mLCH4/gVSadded, respectively. Volatile fatty acids/total inorganic carbon (VFA/TIC) ratio increased from 0.10 to 0.89 when loading increased from 40 to 80gVS/L for GFM. The modified Gompertz model shows a better fit to the experimental results than the first order model with a lower difference between measured and predicted methane yields. The kinetic parameters indicated that the methane production curve on the basis of differences in biodegradability of the pig manure at different growth stages. Copyright © 2014 Elsevier Ltd. All rights reserved.

Storage capacity of subcutaneous fat in Japanese adults.

PubMed

Sato, S; Demura, S; Nakai, M

2015-08-01

On the basis of our previous study, which examined the nonlinear relationship between visceral fat area (VFA) and percent regional fat mass in the trunk, we hypothesise the presence of some storage capacity of subcutaneous fat. This study aimed to examine the storage capacity of subcutaneous fat on the basis of subcutaneous fat area (SFA) and VFA in 791 Japanese adult males and 563 females. Regression analyses by using SFA as a dependent variable and VFA as an independent variable were performed for each group classified by visceral fat obesity (VO): VO (VFA ⩾ 100 cm(2)) and the no-VO (NVO) groups. To statistically identify an optimal critical point for subcutaneous fat accumulation, we changed the cutoff point for the VO group from 50-150 cm(2) in 10-cm(2) increments and confirmed the significance of the correlation between SFA and VFA for each obesity group, the statistical difference in correlations between NVO and VO groups, and the goodness of fit for the two regression lines using the standard error of estimation values. These analyses were conducted for each sex and age (<65 and ⩾ 65 years) group. The critical point for subcutaneous fat accumulation appears at the following cutoff points of VFA: 130 cm(2) in <65-year-old males, 110 cm(2) in ⩾ 65-year-old males and 100 cm(2) in both female groups. These results suggest the presence of some storage capacity of subcutaneous fat. As a further application, these findings may serve to improve the risk assessment of obesity-related diseases.

An innovative online VFA monitoring system for the anerobic process, based on headspace gas chromatography.

PubMed

Boe, Kanokwan; Batstone, Damien John; Angelidaki, Irini

2007-03-01

A new method for online measurement of volatile fatty acids (VFA) in anerobic digesters has been developed based on headspace gas chromatography (HSGC). The method applies ex situ VFA stripping with variable headspace volume and gas analysis by gas chromatography-flame ionization detection (GC-FID). In each extraction, digester sample was acidified with H(3)PO(4) and NaHSO(4), then heated to strip the VFA into the gas phase. The gas was sampled in a low friction glass syringe before injected into the GC for measurement. The system has been tested for online monitoring of a lab-scale CSTR reactor treating manure for more than 6 months and has shown good agreement with off-line analysis. The system is capable of measuring individual VFA components. This is of advantage since specific VFA components such as propionic and butyric acid can give extra information about the process status. Another important advantage of this sensor is that there is no filtration, which makes possible application in high solids environments. The system can thus be easily applied in a full-scale biogas reactor by connecting the system to the liquid circulation loop to obtain fresh sample from the reactor. Local calibration is needed but automatic calibration is also possible using standard addition method. Sampling duration is 25-40 min, depending on the washing duration, and sensor response is 10 min. This is appropriate for full-scale reactors, since dynamics within most biogas reactors are of the order of several hours.

Lactic-fermented egg white improves visceral fat obesity in Japanese subjects-double-blind, placebo-controlled study.

PubMed

Matsuoka, Ryosuke; Kamachi, Keiko; Usuda, Mika; Wang, Wei; Masuda, Yasunobu; Kunou, Masaaki; Tanaka, Akira; Utsunomiya, Kazunori

2017-12-08

It was reported that egg white protein (EWP) reduced body fat in rats. We developed a lactic-fermented egg white (LE) that facilitates the consumption of egg whites by fermenting them with lactobacillus, and were able to study their intake in humans. In this double-blind, placebo-controlled design, we evaluated the effect of LE on visceral fat area (VFA). Participants included 37 adult males and females aged ≥40 years (VFA at navel ≥100 cm 2 ). They were divided into two groups: the control group and the LE group. The control and LE groups consumed drinks containing whey and LE, respectively, for 12 weeks (providing 8 g protein/day). VFA was measured at baseline and at week 12 of intake. Abdominal girth was measured at baseline and at weeks 6 and 12. LE intake decreased VFA significantly compared with baseline (-8.89 cm 2 , p < 0.05), and VFA was significantly lower than that in the control group (+1.71 cm 2 , p < 0.05). The LE group showed significant improvement in the ratio of visceral to subcutaneous fat area compared with baseline and the control group (p < 0.05). The results demonstrated that LE reduces VFA and improves the ratio of visceral to subcutaneous fat area. As other measurement items were not influenced, we concluded that LE improves visceral fat obesity. This clinical trial was retrospectively registered with the University hospital Medical Information Network (UMIN) Center, ( UMIN000026949 ; registered on 11/04/2017; http://www.umin.ac.jp /).

Effects of different rearing systems on growth, small intestinal morphology and selected indices of fermentation status in broilers.

PubMed

Li, Jianhui; Miao, Zhiqiang; Tian, Wenxia; Yang, Yu; Wang, Jundong; Yang, Ying

2017-06-01

A 3×2 factorial experiment was conducted to determine the effects of rearing system and stocking density on the growth performance, intestinal morphology and fermentation status of broilers. Broilers were kept on three rearing systems: floor litter rearing (FRS), plastic net rearing (NRS) and multilayer cage rearing system (CRS), each with two stocking densities (normal and high stocking densities). Results showed that on 7 to 28 days of age, body weight gain appeared as FRS > NRS > CRS. Whereas, CRS significantly enhanced the weight gain of broilers compared with the other systems subsequently. Broilers on FRS had higher counts of cecum Bifidobacteria and Lactobacilli at 28 days of age but had more Escherichia coli and less Bifidobacteria than CRS at 42 days of age. The FRS also decreased volatile fatty acid (VFA) concentration and jejunal villus height-to-crypt depth ratio at all ages. In conclusion, FRS appeared to benefit gut microorganisms during the early growing period along with high body weight gain of broilers, whereas this system might have a harmful effect on subsequent intestinal growth, as indicated by high E. coli, low Bifidobacteria count, low VFA concentration and villus height-to-crypt depth ratio along with low weight gain of broilers. © 2016 Japanese Society of Animal Science.

Nitrogen metabolism of sheep and goats consuming Acacia brevispica and Sesbania sesban

USGS Publications Warehouse

Woodward, A.; Reed, J.D.

1997-01-01

We described the effects of two East African browses, Acacia brevispica and Sesbania sesban, on nitrogen metabolism of sheep and goats. The A. brevispica had a substantial amount of proanthocyanidins (condensed tannins); S. sesban did not. The browses were fed at three levels in combination with vetch (Vicia dasycarpa) and teff straw (Eragrostis abyssinica). Fecal N, N balance, and plasma urea N (PUN) were estimated with intact animals. Ruminal ammonia (RuA) and VFA concentrations were estimated with ruminally fistulated animals. Urinary N loss, PUN, RuA, and VFA concentrations were higher for S. sesban diets than for A. brevispica diets. Fecal N was highest with diets including A. brevispica due to high levels of fecal neutral-detergent insoluble N. Nitrogen retention was highest for diets including S. sesban. Nitrogen retention was adequate for A. brevispica diets because low urinary N compensated for high fecal N. Four hypotheses describe possible effects of tannins on N metabolism: 1) escape of protein from the rumen to the lower tract; 2) increased microbial yield; 3) increase in N-containing endogenous products; and 4) protein made indigestible in tannin-protein complexes. The effect of tannins in A. brevispica on N metabolism can best be described by the formation of indigestible tannin-protein complexes, although increased production of endogenous products is also possible.

Effect of pentachlorophenol and chemical oxygen demand mass concentrations in influent on operational behaviors of upflow anaerobic sludge blanket (UASB) reactor.

PubMed

Shen, Dong-Sheng; He, Ruo; Liu, Xin-Wen; Long, Yan

2006-08-25

Upflow anaerobic sludge blanket (UASB) reactor that was seeded with anaerobic sludge acclimated to chlorophenols was used to investigate the feasibility of anaerobic biotreatment of synthetic wastewater containing pentachlorophenol (PCP) with additional sucrose as carbon source. Two sets of UASB reactors were operated at one time. But the seeded sludge for the two reactors was different and Reactor I was seeded with the sludge that was acclimated to PCP completely for half a year, and Reactor II was seeded with the mixed sludge that was acclimated for half a year to PCP, 4-CP, 3-CP or 2-CP, respectively. The degradation of PCP and the operation fee treating the wastewater are affected by the concentration of MEDS (microorganism easily degradable substrate). So the confirmation of the suitable ratio of [COD] and [PCP] was the key factor of treating the wastewater containing PCP economically and efficiently. During the experiment, the synthetic wastewater with 180.0 mg L(-1) PCP and 1250-10000 mg L(-1) COD could be treated steadily in the experimental Reactor I. The removal efficiency of PCP was more than 99.5% and the removal efficiency of COD was up to 90%. [PCP] (concentration of PCP) in effluent was less than 0.5 mg L(-1). [PCP] in influent could affect proper [COD] (concentration of COD) range in influent that was required for maintenance of steady running of the experimental reactor with a hydraulic retention time (HRT) from 20 to 22 h. [PCP] in influent would directly affect the necessary [COD] in influent when the UASB reactor ran normally and treated the wastewater containing PCP. When [PCP] was 100.4, 151.6 and 180.8 mg L(-1) in influent, respectively, [COD] in influent had to be controlled about 1250-7500, 2500-5000 and 5000 mg L(-1) to maintain the UASB reactor steady running normally and contemporarily ensure that [COD] and [PCP] in effluent were less than 300 and 0.5 mg L(-1), respectively. With the increase of [PCP] in influent, the range of variation of [COD] in influent endured by the UASB reactor was decreasing. The ratios of [COD] and [PCP] in influent could affect removal efficiency of PCP and COD, the concentration of total volatile fatty acids (VFA) in effluent, biogas quantity and methane content in biogas. [PCP] in influent was linearly or semi-logarithmically correlated to [COD] in effluent when [COD] in influent was 5750+/-250 mg L(-1), and so was the relationship between [COD] in influent and [PCP] in effluent when [PCP] in influent was 100.4 or 151.6 mg L(-1), less than the maximum permissible [PCP]. The sources of seeded sludge, the way of sludge acclimation and the characteristics of anaerobic sludge could all affect the UASB reactor capacity treating PCP. When [PCP] were less than 180.8 mg L(-1) for Reactor I and 151.6 mg L(-1) for Reactor II, the variation of [PCP] in influent had little effect on the UASB reactor volume gas production rate and substrate gas production rate. And [VFA] and pH value in effluent were affected a little. Volume biogas production rate and substrate biogas production rate of the UASB reactor were only affected by [COD] and loading rate in influent. But when [PCP] was more than 151.6 mg L(-1) for Reactor II, the biogas production fell quickly and was over 3 days later. [VFA] in effluent from Reactor II increased up to 2198.1 mg L(-1) quickly and the pH value fell to less than 7. Reactor II could not run normally. The component of VFA accumulated quickly was mainly acetate (above 50%). With [PCP] increased from 7.9 to 180.8 mg L(-1) gradually in influent, the methane content in biogas from Reactor II decreased from 70% to 60%, but the reactor could still run normally. Then as for Reactor II, the content of methane have fallen from 75% to 45% or so quickly. And Reactor II could not run steadily. So the conclusion could be drown that too high [PCP] in influent for UASB reactor mainly inhibited the activity of methane-producing bacteria cultures utilizing the acetate.

Effects of a bacteria-based probiotic on ruminal pH, volatile fatty acids and bacterial flora of Holstein calves.

PubMed

Qadis, Abdul Qadir; Goya, Satoru; Ikuta, Kentaro; Yatsu, Minoru; Kimura, Atsushi; Nakanishi, Shusuke; Sato, Shigeru

2014-06-01

Twelve ruminally cannulated Holstein calves (age, 12 ± 3 weeks) were used to identify the effect of a probiotic comprised of Lactobacillus plantarum, Enterococcus faecium and Clostridium butyricum on ruminal components. The calves were adapted to a diet containing a 50% high-concentrate (standard diet) for 1 week, and then, the probiotic was given once daily for 5 days (day 1-5) at 1.5 or 3.0 g/100 kg body weight to groups of four calves each. Four additional calves fed the standard diet without probiotic served as the corresponding control. Ruminal pH was measured continuously throughout the 15-day experimental period. Ruminal fluid was collected via a fistula at a defined time predose and on days 7 and 14 to assess volatile fatty acid (VFA), lactic acid and ammonia-nitrogen concentrations, as well as the bacterial community. The probiotic at either dose improved the reduced 24-hr mean ruminal pH in calves. The circadian patterns of the 1 hr mean ruminal pH were identical between the probiotic doses. In both probiotic groups, ruminal lactic acid concentrations remained significantly lower than that of the control. Probiotic did not affect ruminal VFA concentrations. L. plantarum and C. butyricum were not detected in the rumen of calves given the high-dose probiotic, whereas Enterococcus spp. remained unchanged. These results suggest that calves given a probiotic had stable ruminal pH levels (6.6-6.8), presumably due to the effects of the probiotic on stabilizing rumen-predominant bacteria, which consume greater lactate in the rumen.

Bioaugmentation of Syntrophic Acetate-Oxidizing Culture in Biogas Reactors Exposed to Increasing Levels of Ammonia

PubMed Central

Westerholm, Maria; Levén, Lotta

2012-01-01

The importance of syntrophic acetate oxidation for process stability in methanogenic systems operating at high ammonia concentrations has previously been emphasized. In this study we investigated bioaugmentation of syntrophic acetate-oxidizing (SAO) cultures as a possible method for decreasing the adaptation period of biogas reactors operating at gradually increased ammonia concentrations (1.5 to 11 g NH4+-N/liter). Whole stillage and cattle manure were codigested semicontinuously for about 460 days in four mesophilic anaerobic laboratory-scale reactors, and a fixed volume of SAO culture was added daily to two of the reactors. Reactor performance was evaluated in terms of biogas productivity, methane content, pH, alkalinity, and volatile fatty acid (VFA) content. The decomposition pathway of acetate was analyzed by isotopic tracer experiments, and population dynamics were monitored by quantitative PCR analyses. A shift in dominance from aceticlastic methanogenesis to SAO occurred simultaneously in all reactors, indicating no influence by bioaugmentation on the prevailing pathway. Higher abundances of Clostridium ultunense and Tepidanaerobacter acetatoxydans were associated with bioaugmentation, but no influence on Syntrophaceticus schinkii or the methanogenic population was distinguished. Overloading or accumulation of VFA did not cause notable dynamic effects on the population. Instead, the ammonia concentration had a substantial impact on the abundance level of the microorganisms surveyed. The addition of SAO culture did not affect process performance or stability against ammonia inhibition, and all four reactors deteriorated at high ammonia concentrations. Consequently, these findings further demonstrate the strong influence of ammonia on the methane-producing consortia and on the representative methanization pathway in mesophilic biogas reactors. PMID:22923397

Comparison of updates to the Molly cow model to predict methane production from dairy cows fed pasture.

PubMed

Gregorini, P; Beukes, P C; Hanigan, M D; Waghorn, G; Muetzel, S; McNamara, J P

2013-08-01

Molly is a deterministic, mechanistic, dynamic model representing the digestion, metabolism, and production of a dairy cow. This study compared the predictions of enteric methane production from the original version of Molly (MollyOrigin) and 2 new versions of Molly. Updated versions included new ruminal fiber digestive parameters and animal hormonal parameters (Molly84) and a revised version of digestive and ruminal parameters (Molly85), using 3 different ruminal volatile fatty acid (VFA) stoichiometry constructs to describe the VFA pattern and methane (CH4) production (g of CH4/d). The VFA stoichiometry constructs were the original forage and mixed-diet VFA constructs and a new VFA stoichiometry based on a more recent and larger set of data that includes lactate and valerate production, amylolytic and cellulolytic bacteria, as well as protozoal pools. The models' outputs were challenged using data from 16 dairy cattle 26 mo old [standard error of the mean (SEM)=1.7], 82 (SEM=8.7) d in milk, producing 17 (SEM=0.2) kg of milk/d, and fed fresh-cut ryegrass [dry matter intake=12.3 (SEM=0.3) kg of DM/d] in respiration chambers. Mean observed CH4 production was 266±5.6 SEM (g/d). Mean predicted values for CH4 production were 287 and 258 g/d for MollyOrigin without and with the new VFA construct. Model Molly84 predicted 295 and 288 g of CH4/d with and without the new VFA settings. Model Molly85 predicted the same CH4 production (276 g/d) with or without the new VFA construct. The incorporation of the new VFA construct did not consistently reduce the low prediction error across the versions of Molly evaluated in the present study. The improvements in the Molly versions from MollyOrigin to Molly84 to Molly85 resulted in a decrease in mean square prediction error from 8.6 to 8.3 to 4.3% using the forage diet setting. The majority of the mean square prediction error was apportioned to random bias (e.g., 43, 65, and 70% in MollyOrigin, Molly84, and Molly85, respectively, on the forage setting, showing that with the updated versions a greater proportion of error was random). The slope bias was less than 2% in all cases. We concluded that, of the versions of Molly used for pastoral systems, Molly85 has the capability to predict CH4 production from grass-fed dairy cows with the highest accuracy. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effects of cinnamaldehyde and garlic oil on rumen microbial fermentation in a dual flow continuous culture.

PubMed

Busquet, M; Calsamiglia, S; Ferret, A; Cardozo, P W; Kamel, C

2005-07-01

Eight continuous culture fermentors inoculated with ruminal liquor from heifers fed a 50:50 alfalfa hay:concentrate diet (17.6% crude protein, 28.0% neutral detergent fiber) were used in 3 replicated periods to study the effects of cinnamaldehyde (CIN) and garlic oil (GAR) on rumen microbial fermentation. Treatments were no additive (negative control); 1.25 mg/L (MON) and 12.5 mg/L (MON10) of the ionophore antibiotic monensin (positive control); 31.2 mg/L CIN (CIN) and 312 mg/L (CIN10) of CIN; and 31.2 mg/L GAR (GAR) and 312 mg/L (GAR10) of GAR (Allium sativa). The MON10 caused expected changes in microbial fermentation patterns (a decrease in fiber digestion, ammonia N concentration, and proportions of acetate and butyrate; an increase in the proportion of propionate; and a trend to increase small peptide plus AA N concentration). The CIN decreased the proportion of acetate and branch-chained volatile fatty acids (VFA) and increased the proportion of propionate; CIN10 decreased the proportion of acetate and increased the proportion of butyrate compared with the control. The GAR10 increased the proportion of propionate and butyrate and decreased the proportion of acetate and branch-chained VFA compared with the control. The GAR10 also increased the small peptide plus amino acid N concentration, although no effects were observed on large peptides or ammonia N concentrations. The CIN and GAR10 resulted in similar effects as monensin, with the exception of the effects on the molar proportion of butyrate, which suggests that they might have a different mode of action in affecting in vitro microbial fermentation.

Effects of three methane mitigation agents on parameters of kinetics of total and hydrogen gas production, ruminal fermentation and hydrogen balance using in vitro technique.

PubMed

Wang, Min; Wang, Rong; Yang, Shan; Deng, Jin Ping; Tang, Shao Xun; Tan, Zhi Liang

2016-02-01

Methane (CH4 ) can be mitigated through directly inhibiting methanogen activity and starving methanogens by hydrogen (H2 ) sink. Three types of mechanism (i.e. bromoethanesulphonate (BES), nitrate and emodin) and doses of CH4 mitigation agents were employed to investigate their pathways of CH4 inhibition. Results indicated that both BES and emodin inhibited CH4 production and altered H2 balance, which could be accompanied by decreased dry matter disappearance (DMD), fractional rate of gH2 formation, volatile fatty acid (VFA) production, ability to produce and use reducing equivalences and molecular H2 , and increased final asymptotic gH2 production, time to the peak of gH2 , discrete lag time of gH2 production and fermentation efficiency. However, emodin decreased gas volume produced by rapidly fermentable components of substrate and the rate of fermentation at early stage of incubation, while BES supplementation inhibited gas volume produced by both rapidly and slowly fermentable components of substrate and the rate of fermentation at middle or late stage of incubation. The nitrate supplementation inhibited CH4 production without affecting VFA profile, because of its dual role as H2 sink and being toxic to methanogens. Nitrate supplementation had more complicated pattern of fermentation, VFA production and profile and H2 balance in comparison to BES and emodin supplementation. © 2015 Japanese Society of Animal Science.

Rumen morphometrics and the effect of digesta pH and volume on volatile fatty acid absorption.

PubMed

Melo, L Q; Costa, S F; Lopes, F; Guerreiro, M C; Armentano, L E; Pereira, M N

2013-04-01

The effects of rumen digesta volume and pH on VFA absorption and its relation to rumen wall morphology were evaluated. Nine rumen cannulated cows formed 3 groups based on desired variation in rumen morphology: The High group was formed by Holsteins yielding 25.9 kg milk/d and fed on a high-grain total mixed ration (TMR); the Medium group by Holstein-Zebu crossbreds yielding 12.3 kg milk/d and fed on corn silage, tropical pasture, and a commercial concentrate; and the Dry group by nonlactating grazing Jerseys fed exclusively on tropical pasture. Within each group, a sequence of 3 ruminal conditions was induced on each cow in 3 × 3 Latin Squares, with 7-d periods: high digesta volume and high pH (HVHP), low volume and high pH (LVHP), and low volume and low pH (LVLP). Rumen mucosa was biopsied on the first day of Period 1. Ruminal morphometric variables evaluated were mitotic index, absorptive surface and papillae number per square centimeter of wall, area per papillae, papillae area as a percentage of absorptive surface, and epithelium, keratinized layer, and nonkeratinized layer thickness. There was marked variation in rumen morphology among the groups of cows. Grazing Jerseys had decreased rumen wall absorptive surface area and basal cells mitotic index, and increased thickness of the epithelium and of the keratin layer compared with cows receiving concentrates. Mean rumen pH throughout the 4 h sampling period was: 6.78 for HVHP, 7.08 for LVHP, and 5.90 for LVLP (P < 0.01). The capacity of the rumen wall to absorb VFA was estimated by the Valerate/CrEDTA technique. The fractional exponential decay rate for the ratio of valeric acid to Cr (k Val/Cr) was determined by rumen digesta sampling at 20-min intervals during 4 h, after the mixing of markers and the return of the evacuated ruminal content. The k Val/Cr values for treatments HVHP, LVHP, and LVLP were, respectively: 19.6, 23.9, and 35.0 %/h (SEM = 2.01; P = 0.21 for contrast HVHP vs. LVHP and P < 0.01 for contrast LVHP vs. LVLP). The k Val/Cr was faster under low pH, but decreasing digesta volume under high pH did not elicit such a response. The correlation between the absorptive surface area per square centimeter of rumen wall and the mean of the 3 k Val/Cr values of each cow was 0.90 (P < 0.01). Cows capable of maintaining a less-acidic rumen environment had greater inflow of water into the digestive cavity, had a more developed rumen mucosa, and were more efficient VFA absorbers.

Reactor performance of a 750 m(3) anaerobic digestion plant: varied substrate input conditions impacting methanogenic community.

PubMed

Wagner, Andreas Otto; Malin, Cornelia; Lins, Philipp; Gstraunthaler, Gudrun; Illmer, Paul

2014-10-01

A 750 m(3) anaerobic digester was studied over a half year period including a shift from good reactor performance to a reduced one. Various abiotic parameters like volatile fatty acids (VFA) (formic-, acetic-, propionic-, (iso-)butyric-, (iso-)valeric-, lactic acid), total C, total N, NH4 -N, and total proteins, as well as the organic matter content and dry mass were determined. In addition several process parameters such as temperature, pH, retention time and input of substrate and the concentrations of CH4, H2, CO2 and H2S within the reactor were monitored continuously. The present study aimed at the investigation of the abundance of acetogens and total cell numbers and the microbial methanogenic community as derived from PCR-dHPLC analysis in order to put it into context with the determined abiotic parameters. An influence of substrate quantity on the efficiency of the anaerobic digestion process was found as well as a shift from a hydrogenotrophic in times of good reactor performance towards an acetoclastic dominated methanogenic community in times of reduced reactor performance. After the change in substrate conditions it took the methano-archaeal community about 5-6 weeks to be affected but then changes occurred quickly. Copyright © 2014 Elsevier Ltd. All rights reserved.

Instability mechanisms and early warning indicators for mesophilic anaerobic digestion of vegetable waste.

PubMed

Li, Dong; Chen, Lin; Liu, Xiaofeng; Mei, Zili; Ren, Haiwei; Cao, Qin; Yan, Zhiying

2017-12-01

In order to elucidate the instability mechanism, screen early warning indicators, and propose control measures, the mesophilic digestion of vegetable waste (VW) was carried out at organic loading rates (OLR) of 0.5, 1.0, and 1.5g volatile solid (VS)/(Ld). The process parameters, including biogas components, volatile fatty acids (VFA), ammonia, pH, total alkalinity (TA), bicarbonate alkalinity (BA), and intermediate alkalinity (IA), were monitored every day. Digestion was inhibited at OLR of 1.5gVS/(Ld). The primary causes of instability are a high sugar and negligible ammonia content, in addition to the feed without effluent recirculation, which led to BA loss. The ratios of CH 4 /CO 2 , VFA/BA, propionate, n-butyrate and iso-valerate were selected as early warning indicators. In order to maintain the digestion of VW at a high OLR, control measures including effluent recirculation and trace element addition are recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

Clinical Evaluation of an Affordable Qualitative Viral Failure Assay for HIV Using Dried Blood Spots in Uganda.

PubMed

Balinda, Sheila N; Ondoa, Pascale; Obuku, Ekwaro A; Kliphuis, Aletta; Egau, Isaac; Bronze, Michelle; Kasambula, Lordwin; Schuurman, Rob; Spieker, Nicole; Rinke de Wit, Tobias F; Kityo, Cissy

2016-01-01

WHO recommends regular viral load (VL) monitoring of patients on antiretroviral therapy (ART) for timely detection of virological failure, prevention of acquired HIV drug resistance (HIVDR) and avoiding unnecessary switching to second-line ART. However, the cost and complexity of routine VL testing remains prohibitive in most resource limited settings (RLS). We evaluated a simple, low-cost, qualitative viral-failure assay (VFA) on dried blood spots (DBS) in three clinical settings in Uganda. We conducted a cross-sectional diagnostic accuracy study in three HIV/AIDS treatment centres at the Joint Clinical Research Centre in Uganda. The VFA employs semi-quantitative detection of HIV-1 RNA amplified from the LTR gene. We used paired dry blood spot (DBS) and plasma with the COBASAmpliPrep/COBASTaqMan, Roche version 2 (VLref) as the reference assay. We used the VFA at two thresholds of viral load, (>5,000 or >1,000 copies/ml). 496 paired VFA and VLref results were available for comparative analysis. Overall, VFA demonstrated 78.4% sensitivity, (95% CI: 69.7%-87.1%), 93% specificity (95% CI: 89.7%-96.4%), 89.3% accuracy (95% CI: 85%-92%) and an agreement kappa = 0.72 as compared to the VLref. The predictive values of positivity and negativity among patients on ART for >12 months were 72.7% and 99.3%, respectively. VFA allowed 89% of correct classification of VF. Only 11% of the patients were misclassified with the potential of unnecessary or late switch to second-line ART. Our findings present an opportunity to roll out simple and affordable VL monitoring for HIV-1 treatment in RLS.

Impact of narasin on manure composition, microbial ecology, and gas emissions from finishing pigs fed either a corn-soybean meal or a corn-soybean meal-dried distillers grains with solubles diets.

PubMed

Kerr, Brian J; Trabue, Steven L; van Weelden, Mark B; Andersen, Daniel S; Pepple, Laura M

2018-04-14

An experiment was conducted to determine the effect of feeding finishing pigs a corn-soybean (CSBM) diet or a CSBM diet supplemented with 30% dried distillers grains with solubles (DDGS), in combination with or without a growth-promoting ionophore (0 or 30 mg narasin/kg of diet), has on manure composition, microbial ecology, and gas emissions. Two separate groups of 24 gilts (initial BW = 145.1 kg, SD = 7.8 kg) were allotted to individual metabolism crates that allowed for total but separate collection of feces and urine during the 48-d collection period. After each of the twice-daily feedings, feces and urine from each crate was collected and added to its assigned enclosed manure storage tank. Each tank contained an individual fan system that pulled a constant stream of air over the manure surface for 2 wk prior to air (day 52) and manure sampling (day 53). After manure sampling, the manure in the tanks was dumped and the tanks cleaned for the second group of pigs. Except for total manure Ca and P output as a percent of intake and for manure methane product rate and biochemical methane potential (P ≤ 0.08), there were no interactions between diet composition and narasin supplementation. Narasin supplementation resulted in increased manure C (P = 0.05), increased manure DM, C, S, Ca, and phosphorus as a percent of animal intake (P ≤ 0.07), and increased manure volatile solids and foaming capacity (P ≤ 0.09). No effect of narasin supplementation was noted on manure VFA concentrations or any of the gas emission parameters measured (P ≥ 0.29). In contrast, feeding finishing pigs a diet containing DDGS dramatically affected manure composition as indicated by increased concentration of DM, C, ammonia, N, and total and volatile solids (P = 0.01), increased manure DM, N, and C as a percent of animal intake (P = 0.01), increased manure total VFA and phenols (P ≤ 0.05), decreased gas emissions of ammonia and volatile sulfur compounds (VSC; P = 0.01), increased emissions of phenols and indoles (P ≤ 0.06), decreased methane production rate (P = 0.01), and slight differences in microbial ecology (R ≤ 0.47). In conclusion, feeding a diet which contains an elevated level of indigestible fiber (i.e., DDGS) resulted in more fiber in the manure which therefore dramatically affected manure composition, gas emissions, and microbial ecology, while narasin supplementation to the diet did not exhibit a significant effect on any of these parameters in the resultant swine manure.

Pretreatment of macroalgae for volatile fatty acid production.

PubMed

Pham, Thi Nhan; Um, Youngsoon; Yoon, Hyon Hee

2013-10-01

In this study, a novel method was proposed for the biological pretreatment of macroalgae (Laminaria japonica, Pachymeniopsis elliptica, and Enteromorpha crinita) for production of volatile fatty acid (VFA) by anaerobic fermentation. The amount of VFA produced from 40 g/L of L. japonica increased from 8.3 g/L (control) to 15.6 g/L when it was biologically pretreated with Vibrio harveyi. The biological treatment of L. japonica with Vibrio spp. was most effective likely due to the alginate lyase activity of Vibrio spp. However, a considerable effect was also observed after biological pretreatment of P. elliptica and E. crinita, which are red and green algae, respectively. Alkaline pretreatment of 40 g/L of L. japonica with 0.5 N NaOH resulted in an increase of VFA production to 12.2 g/L. These results indicate that VFA production from macroalgae can be significantly enhanced using the proposed biological pretreatments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rumen fermentation and liveweight gain in beef cattle treated with monensin and grazing lush forage.

PubMed

Packer, E L; Clayton, E H; Cusack, P M V

2011-09-01

To determine the prevalence of subacute rumen acidosis (SARA) in beef cattle grazing lush pasture and the effect of monensin on reducing SARA and improving animal performance. Commercial Angus and Murray Grey steers received a monensin slow-release capsule (n = 19) or remained untreated (n = 19). Cattle grazed an oats crop or tetraploid ryegrass pasture for a total of 91 days. Rumen fluid pH, volatile fatty acids (VFA) and lactic acid concentrations and body weight data were collected prior to treatment and again 28, 56 and 91 days after treatment. Changes in measures over time were analysed using mixed model repeated measures analysis. Differences in average daily gain between treatment groups were determined. The prevalence of SARA was low during the study, with only one animal satisfying criteria for SARA at one time point. Cattle treated with monensin capsules were 11.9 kg heavier at the completion of the study compared with untreated controls (414.5 ± 3.88 kg vs 402.6 ± 4.03 kg, P = 0.04). Rumen VFA and L- and D-lactate levels did not differ between cattle treated with monensin and untreated cattle. However, the ratio of propionate to acetate plus two times butyrate was higher (P < 0.001) when cattle were treated with monensin. Subacute rumen acidosis was not consistently detected under the conditions of the study. The higher body weight of cattle treated with monensin may have been due to improved energy utilisation of the pasture, indicated by increased propionate proportions in the rumen, rather than prevention of SARA. © 2011 The Authors. Australian Veterinary Journal © 2011 Australian Veterinary Association.

Effects of Aspergillus Oryzae Culture and 2-Hydroxy-4-(Methylthio)-Butanoic Acid on In vitro Rumen Fermentation and Microbial Populations between Different Roughage Sources.

PubMed

Sun, H; Wu, Y M; Wang, Y M; Liu, J X; Myung, K H

2014-09-01

An in vitro experiment was conducted to evaluate the effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on rumen fermentation and microbial populations between different roughage sources. Two roughage sources (Chinese wild rye [CWR] vs corn silage [CS]) were assigned in a 2×3 factorial arrangement with HMB (0 or 15 mg) and AOC (0, 3, or 6 mg). Gas production (GP), microbial protein (MCP) and total volatile fatty acid (VFA) were increased in response to addition of HMB and AOC (p<0.01) for the two roughages. The HMB and AOC showed inconsistent effects on ammonia-N with different substrates. For CWR, neither HMB nor AOC had significant effect on molar proportion of individual VFA. For CS, acetate was increased (p = 0.02) and butyrate was decreased (p<0.01) by adding HMB and AOC. Increase of propionate was only occurred with AOC (p<0.01). Populations of protozoa (p≤0.03) and fungi (p≤0.02) of CWR were differently influenced by HMB and AOC. Percentages of F. succinogenes, R. albus, and R. flavefaciens (p<0.01) increased when AOC was added to CWR. For CS, HMB decreased the protozoa population (p = 0.01) and increased the populations of F. succinogenes and R. albus (p≤0.03). Populations of fungi, F. succinogenes (p = 0.02) and R. flavefacien (p = 0.03) were increased by adding AOC. The HMB×AOC interactions were noted in MCP, fungi and R. flavefacien for CWR and GP, ammonia-N, MCP, total VFA, propionate, acetate/propionate (A/P) and R. albus for CS. It is inferred that addition of HMB and AOC could influence rumen fermentation of forages by increasing the number of rumen microbes.

Variable flip angle 3D ultrashort echo time (UTE) T1 mapping of mouse lung: A repeatability assessment.

PubMed

Alamidi, Daniel F; Smailagic, Amir; Bidar, Abdel W; Parker, Nicole S; Olsson, Marita; Hockings, Paul D; Lagerstrand, Kerstin M; Olsson, Lars E

2018-03-08

Lung T 1 is a potential translational biomarker of lung disease. The precision and repeatability of variable flip angle (VFA) T 1 mapping using modern 3D ultrashort echo time (UTE) imaging of the whole lung needs to be established before it can be used to assess response to disease and therapy. To evaluate the feasibility of regional lung T 1 quantification with VFA 3D-UTE and to investigate long- and short-term T 1 repeatability in the lungs of naive mice. Prospective preclinical animal study. Eight naive mice and phantoms. 3D free-breathing radial UTE (8 μs) at 4.7T. VFA 3D-UTE T 1 calculations were validated against T 1 values measured with inversion recovery (IR) in phantoms. Lung T 1 and proton density (S 0 ) measurements of whole lung and muscle were repeated five times over 1 month in free-breathing naive mice. Two consecutive T 1 measurements were performed during one of the imaging sessions. Agreement in T 1 between VFA 3D-UTE and IR in phantoms was assessed using Bland-Altman and Pearson 's correlation analysis. The T 1 repeatability in mice was evaluated using coefficient of variation (CV), repeated-measures analysis of variance (ANOVA), and paired t-test. Good T 1 agreement between the VFA 3D-UTE and IR methods was found in phantoms. T 1 in lung and muscle showed a 5% and 3% CV (1255 ± 63 msec and 1432 ± 42 msec, respectively, mean ± SD) with no changes in T 1 or S 0 over a month. Consecutive measurements resulted in an increase of 2% in both lung T 1 and S 0 . VFA 3D-UTE shows promise as a reliable T 1 mapping method that enables full lung coverage, high signal-to-noise ratio (∼25), and spatial resolution (300 μm) in freely breathing animals. The precision of the VFA 3D-UTE method will enable better design and powering of studies. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018. © 2018 International Society for Magnetic Resonance in Medicine.

Supine vs decubitus lateral patient positioning in vertebral fracture assessment.

PubMed

Paggiosi, Margaret Anne; Finigan, Judith; Peel, Nicola; Eastell, Richard; Ferrar, Lynne

2012-01-01

In vertebral fracture assessment (VFA), lateral scans are obtained with the patient positioned supine (C-arm densitometers) or lateral decubitus (fixed-arm densitometers). We aimed to determine the impact of positioning on image quality and fracture definition. We performed supine and decubitus lateral VFA in 50 postmenopausal women and used the algorithm-based qualitative method to identify vertebral fractures. We compared the 2 techniques for the identification of fractures (kappa analysis) and compared the numbers of unreadable vertebrae (indiscernible endplates) and vertebrae that were projected obliquely (Wilcoxon matched-pairs signed-rank test). The kappa score for agreement between the VFA techniques (to identify women with vertebral fractures) was 0.84 (95% confidence interval [CI]: 0.68-0.99), and for agreement with fracture assessments made from radiographs, kappa was 0.76 (95% CI: 0.57-0.94) for both supine and decubitus lateral VFA. There were more unreadable vertebrae with supine lateral (48 vertebrae in supine lateral compared with 14 in decubitus lateral; p=0.001), but oblique projection was less common (93 vertebrae compared with 145 in decubitus lateral; p=0.002). We conclude that there were significantly different projection effects with supine and decubitus lateral VFA, but these differences did not influence the identification of vertebral fractures in our study sample. Copyright © 2012 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

EPIGENETIC REGULATION IN BOVINE CELLS: NUTRIENT-INDUCED MODULATION OF GENE EXPRESSION AND CELLULAR FUNCTIONS

USDA-ARS?s Scientific Manuscript database

Research on epigenetics and nutrigenetics, the genome-nutrient interface is in its infancy with respect to livestock species. Ruminant species have evolved to metabolize short-chain fatty acids (VFA) to fulfill up to 70% of their energy requirements. Our studies revealed that VFA, especially butyr...

Pre-aeration of food waste to augment acidogenic process at higher organic load: Valorizing biohydrogen, volatile fatty acids and biohythane.

PubMed

Sarkar, Omprakash; Venkata Mohan, S

2017-10-01

Application of pre-aeration (AS) to waste prior to feeding was evaluated on acidogenic process in a semi-pilot scale biosystem for the production of biobased products (biohydrogen, volatile fatty acids (VFA) and biohythane) from food waste. Oxygen assisted in pre-hydrolysis of waste along with the suppression of methanogenic activity resulting in enhanced acidogenic product formation. AS operation resulted in 97% improvement in hydrogen conversion efficiency (HCE) and 10% more VFA production than the control. Increasing the organic load (OL) of food waste in association with AS application improved the productivity. The application of AS also influenced concentration and composition of fatty acid. Highest fraction of acetic (5.3g/l), butyric (0.7g/l) and propionic acid (0.84g/l) was achieved at higher OL (100g COD/l) with good degree of acidification (DOA). AS strategy showed positive influence on biofuel (biohydrogen and biohythane) production along with the biosynthesis of short chain fatty acids functioning as a low-cost pretreatment strategy in a single stage bioprocess. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of polyhydroxyalkanoates (PHA) by bacterial consortium from excess sludge fermentation liquid at laboratory and pilot scales.

PubMed

Jia, Qianqian; Xiong, Huilei; Wang, Hui; Shi, Hanchang; Sheng, Xinying; Sun, Run; Chen, Guoqiang

2014-11-01

The generation of polyhydroxyalkanoates (PHA) from excess sludge fermentation liquid (SFL) was studied at lab and pilot scale. A PHA-accumulated bacterial consortium (S-150) was isolated from activated sludge using simulated SFL (S-SFL) contained high concentration volatile fatty acids (VFA) and nitrogen. The maximal PHA content accounted for 59.18% in S-SFL and dropped to 23.47% in actual SFL (L-SFL) of the dry cell weight (DCW) at lab scale. The pilot-scale integrated system comprised an anaerobic fermentation reactor (AFR), a ceramic membrane system (CMS) and a PHA production bio-reactor (PHAR). The PHA content from pilot-scale SFL (P-SFL) finally reached to 59.47% DCW with the maximal PHA yield coefficient (YP/S) of 0.17 g PHA/g COD. The results indicated that VFA-containing SFL was suitable for PHA production. The adverse impact of excess nitrogen and non-VFAs in SFL might be eliminated by pilot-scale domestication, which might resulted in community structure optimization and substrate selective ability improvement of S-150. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of a Bacteria-Based Probiotic on Ruminal pH, Volatile Fatty Acids and Bacterial Flora of Holstein Calves

PubMed Central

QADIS, Abdul Qadir; GOYA, Satoru; IKUTA, Kentaro; YATSU, Minoru; KIMURA, Atsushi; NAKANISHI, Shusuke; SATO, Shigeru

2014-01-01

ABSTRACT Twelve ruminally cannulated Holstein calves (age, 12 ± 3 weeks) were used to identify the effect of a probiotic comprised of Lactobacillus plantarum, Enterococcus faecium and Clostridium butyricum on ruminal components. The calves were adapted to a diet containing a 50% high-concentrate (standard diet) for 1 week, and then, the probiotic was given once daily for 5 days (day 1–5) at 1.5 or 3.0 g/100 kg body weight to groups of four calves each. Four additional calves fed the standard diet without probiotic served as the corresponding control. Ruminal pH was measured continuously throughout the 15-day experimental period. Ruminal fluid was collected via a fistula at a defined time predose and on days 7 and 14 to assess volatile fatty acid (VFA), lactic acid and ammonia-nitrogen concentrations, as well as the bacterial community. The probiotic at either dose improved the reduced 24-hr mean ruminal pH in calves. The circadian patterns of the 1 hr mean ruminal pH were identical between the probiotic doses. In both probiotic groups, ruminal lactic acid concentrations remained significantly lower than that of the control. Probiotic did not affect ruminal VFA concentrations. L. plantarum and C. butyricum were not detected in the rumen of calves given the high-dose probiotic, whereas Enterococcus spp. remained unchanged. These results suggest that calves given a probiotic had stable ruminal pH levels (6.6–6.8), presumably due to the effects of the probiotic on stabilizing rumen-predominant bacteria, which consume greater lactate in the rumen. PMID:24614603

Application of titration methods for measuring the contents of ammonium nitrogen and volatile fatty acids in agricultural biogas plants.

PubMed

Piątek, Michał; Lisowski, Aleksander; Lisowska, Barbara

2017-12-20

The aim of our research was to assess a relatively new method of estimating ammonium nitrogen concentration in anaerobic digestion of plant substrates. We analysed our own data, received from the anaerobic digestion of maize silage (PM), as well as data published by Purser et al. (2014) who measured energy crops and slurry (ECS), and food waste (FW). In our study, the process was monitored for VFA content that was determined by gas chromatography, and for the content of ammonium nitrogen determined using the HACH LANGE LCK 303 cuvette test. We created polynomial regression models that bind the content of ammonium nitrogen with the volume of H 2 SO 4 used to titrate the sample from initial pH to pH 5. To estimate parameters of model, the PM dataset was used. The obtained models were positively validated using ECS and FW datasets. Our results confirmed the effectiveness of the Purser et al. method with an average absolute error of less than 223mgl -1 of the VFA concentration, which was approximately 20-times less than the level that caused inhibition. In conclusion, we can affirm the suitability of using titration methods to assess the ammonium nitrogen content of bioreactors with a stable composition. Copyright © 2017 Elsevier B.V. All rights reserved.

In vitro screening of natural feed additives from crustaceans, diatoms, seaweeds and plant extracts to manipulate rumen fermentation.

PubMed

Belanche, Alejandro; Ramos-Morales, Eva; Newbold, C Jamie

2016-07-01

Eight natural products from animal, unicellular algae, brown seaweed and plant origins were chosen according to their theoretical antimicrobial activity: Diatomaceous earths (DE), insoluble chitosan (ICHI), soluble chitosan (CHI), seaweed meal (SWM), Ascophyllum nodosum (ASC), Laminaria digitata (LAM), neem oil (NOIL) and an ivy fruit extract rich in saponins (IVY). Dose-response incubations were conducted to determine their effect on rumen fermentation pattern and gas production, while their anti-protozoal activity was tested using (14) C-labelled bacteria. DE, SWM, NOIL and ICHI had very small effects on rumen function when used at inclusion rate up to 2 g L(-1) . ASC had anti-protozoal effects (up to -23%) promoting a decrease in gas production and methanogenesis (-15%). LAM increased VFA production (+7%) and shifted from butyrate to acetate. CHI also shifted fermentation towards propionate production and lower methane (-23%) and protozoal activity (-56%). IVY decreased protozoal activity (-39%) and ammonia concentration (-56%), as well as increased feed fermentation (+11% VFA concentration) and shifted from acetate to propionate production. ASC, LAM, CHI and IVY showed promising potential in vitro as feed additives to improve rumen function, thus more research is needed to investigate their mode of action in the rumen microbial ecosystem. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Evaluation of nutritional and economic feed values of spent coffee grounds and Artemisia princeps residues as a ruminant feed using in vitro ruminal fermentation

PubMed Central

Seo, Jakyeom; Jung, Jae Keun

2015-01-01

Much research on animal feed has focused on finding alternative feed ingredients that can replace conventional ones (e.g., grains and beans) to reduce feed costs. The objective of this study was to evaluate the economic, as well as nutritional value of spent coffee grounds (SCG) and Japanese mugwort (Artemisia princeps) residues (APR) as alternative feed ingredients for ruminants. We also investigated whether pre-fermentation using Lactobacillus spp. was a feasible way to increase the feed value of these by-products. Chemical analyses and an in vitro study were conducted for SCG, APR, and their pre-fermented forms. All the experimental diets for in vitro ruminal fermentation were formulated to contain a similar composition of crude protein, neutral detergent fiber and total digestible nutrients at 1x maintenance feed intake based on the dairy National Research Council (NRC). The control diet was composed of ryegrass, corn, soybean meal, whereas the treatments consisted of SCG, SCG fermented with Lactobacillus spp. (FSCG), APR, and its fermented form (FAPR). The treatment diets replaced 100 g/kg dry matter (DM) of the feed ingredients in the control. Costs were lower for the all treatments, except FAPR, than that of the control. After 24-h incubation, the NDF digestibility of the diets containing SCG and its fermented form were significantly lower than those of the other diets (P < 0.01); pre-fermentation tended to increase NDF digestibility (P = 0.07), especially for APR. Supplementation of SCG significantly decreased total gas production (ml/g DM) after 24-h fermentation in comparison with the control (P < 0.05); however, there were no significant differences between the control and the SCG or the APR diets in total gas production, as expressed per Korean Won (KRW). Diets supplemented with SCG or FSCG tended to have a higher total volatile fatty acid (VFA) concentration, expressed as per KRW, compared with the control (P = 0.06). Conversely, the fermentation process of SCG and APR significantly decreased total gas production and VFA production as expressed per KRW (P < 0.05). Because of their nutrient composition and relatively lower cost, we concluded that SCG and APR could be used as alternative feed sources, replacing conventional feed ingredients. However, pre-fermentation of agricultural by-products, such as SCG and APR, may be inappropriate for improving their nutritive considering the increase in production costs. PMID:26528409

Evaluation of nutritional and economic feed values of spent coffee grounds and Artemisia princeps residues as a ruminant feed using in vitro ruminal fermentation.

PubMed

Seo, Jakyeom; Jung, Jae Keun; Seo, Seongwon

2015-01-01

Much research on animal feed has focused on finding alternative feed ingredients that can replace conventional ones (e.g., grains and beans) to reduce feed costs. The objective of this study was to evaluate the economic, as well as nutritional value of spent coffee grounds (SCG) and Japanese mugwort (Artemisia princeps) residues (APR) as alternative feed ingredients for ruminants. We also investigated whether pre-fermentation using Lactobacillus spp. was a feasible way to increase the feed value of these by-products. Chemical analyses and an in vitro study were conducted for SCG, APR, and their pre-fermented forms. All the experimental diets for in vitro ruminal fermentation were formulated to contain a similar composition of crude protein, neutral detergent fiber and total digestible nutrients at 1x maintenance feed intake based on the dairy National Research Council (NRC). The control diet was composed of ryegrass, corn, soybean meal, whereas the treatments consisted of SCG, SCG fermented with Lactobacillus spp. (FSCG), APR, and its fermented form (FAPR). The treatment diets replaced 100 g/kg dry matter (DM) of the feed ingredients in the control. Costs were lower for the all treatments, except FAPR, than that of the control. After 24-h incubation, the NDF digestibility of the diets containing SCG and its fermented form were significantly lower than those of the other diets (P < 0.01); pre-fermentation tended to increase NDF digestibility (P = 0.07), especially for APR. Supplementation of SCG significantly decreased total gas production (ml/g DM) after 24-h fermentation in comparison with the control (P < 0.05); however, there were no significant differences between the control and the SCG or the APR diets in total gas production, as expressed per Korean Won (KRW). Diets supplemented with SCG or FSCG tended to have a higher total volatile fatty acid (VFA) concentration, expressed as per KRW, compared with the control (P = 0.06). Conversely, the fermentation process of SCG and APR significantly decreased total gas production and VFA production as expressed per KRW (P < 0.05). Because of their nutrient composition and relatively lower cost, we concluded that SCG and APR could be used as alternative feed sources, replacing conventional feed ingredients. However, pre-fermentation of agricultural by-products, such as SCG and APR, may be inappropriate for improving their nutritive considering the increase in production costs.

Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling.

PubMed

Amulya, K; Jukuri, Srinivas; Venkata Mohan, S

2015-01-01

Polyhydroxyalkanoates (PHA) production was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the production of bio-hydrogen (bio-H2) via acidogenic fermentation. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA production, which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA production). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell weight (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA production with simultaneous waste remediation in the framework of biorefinery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Organic loading rate effect on the acidogenesis of cheese whey: a comparison between UASB and SBR reactors.

PubMed

Calero, R; Iglesias-Iglesias, R; Kennes, C; Veiga, M C

2017-09-16

Volatile fatty acids (VFA) production and degree of acidification (DA) were investigated in the anaerobic treatment of cheese whey by comparison of two processes: a continuous process using a laboratory upflow anaerobic sludge blanket (UASB) reactor and a discontinuous process using a sequencing batch reactor (SBR). The main purpose of this work was to study the organic loading rate (OLR) effect on the yield of VFA in two kinds of reactors. The predominant products in the acidogenic process in both reactors were: acetate, propionate, butyrate and valerate. The maximum DA obtained was 98% in an SBR at OLR of 2.7 g COD L -1 d -1 , and 97% in the UASB at OLR at 15.1 g COD L -1 d -1 . The results revealed that the UASB reactor was more efficient at a medium OLR with a higher VFA yield, while with the SBR reactor, the maximum acidification was obtained at a lower OLR with changes in the VFA profile at different OLRs applied.

Treatment of winery wastewater by an anaerobic sequencing batch reactor.

PubMed

Ruíz, C; Torrijos, M; Sousbie, P; Lebrato Martínez, J; Moletta, R; Delgenès, J P

2002-01-01

Treatment of winery wastewater was investigated using an anaerobic sequencing batch reactor (ASBR). Biogas production rate was monitored and permitted the automation of the bioreactor by a simple control system. The reactor was operated at an organic loading rate (ORL) around 8.6 gCOD/L.d with soluble chemical oxygen demand (COD) removal efficiency greater than 98%, hydraulic retention time (HRT) of 2.2 d and a specific organic loading rate (SOLR) of 0.96 gCOD/gVSS.d. The kinetics of COD and VFA removal were investigated for winery wastewater and for simple compounds such as ethanol, which is a major component of winery effluent, and acetate, which is the main volatile fatty acid (VFA) produced. The comparison of the profiles obtained with the 3 substrates shows that, overall, the acidification of the organic matter and the methanisation of the VFA follow zero order reactions, in the operating conditions of our study. The effect on the gas production rate resulted in two level periods separated by a sharp break when the acidification stage was finished and only the breaking down of the VFA continued.

Ruminant Nutrition Symposium: Productivity, digestion, and health responses to hindgut acidosis in ruminants.

PubMed

Gressley, T F; Hall, M B; Armentano, L E

2011-04-01

Microbial fermentation of carbohydrates in the hindgut of dairy cattle is responsible for 5 to 10% of total-tract carbohydrate digestion. When dietary, animal, or environmental factors contribute to abnormal, excessive flow of fermentable carbohydrates from the small intestine, hindgut acidosis can occur. Hindgut acidosis is characterized by increased rates of production of short-chain fatty acids including lactic acid, decreased digesta pH, and damage to gut epithelium as evidenced by the appearance of mucin casts in feces. Hindgut acidosis is more likely to occur in high-producing animals fed diets with relatively greater proportions of grains and lesser proportions of forage. In these animals, ruminal acidosis and poor selective retention of fermentable carbohydrates by the rumen will increase carbohydrate flow to the hindgut. In more severe situations, hindgut acidosis is characterized by an inflammatory response; the resulting breach of the barrier between animal and digesta may contribute to laminitis and other disorders. In a research setting, effects of increased hindgut fermentation have been evaluated using pulse-dose or continuous abomasal infusions of varying amounts of fermentable carbohydrates. Continuous small-dose abomasal infusions of 1 kg/d of pectin or fructans into lactating cows resulted in decreased diet digestibility and decreased milk fat percentage without affecting fecal pH or VFA concentrations. The decreased diet digestibility likely resulted from increased bulk in the digestive tract or from increased digesta passage rate, reducing exposure of the digesta to intestinal enzymes and epithelial absorptive surfaces. The same mechanism is proposed to explain the decreased milk fat percentage because only milk concentrations of long-chain fatty acids were decreased. Pulse-dose abomasal fructan infusions (1 g/kg of BW) into steers resulted in watery feces, decreased fecal pH, and increased fecal VFA concentrations, without causing an inflammatory response. Daily 12-h abomasal infusions of a large dose of starch (~4 kg/d) have also induced hindgut acidosis as indicated by decreased fecal pH and watery feces. On the farm, watery or foamy feces or presence of mucin casts in feces may indicate hindgut acidosis. In summary, hindgut acidosis occurs because of relatively high rates of large intestinal fermentation, likely due to digestive dysfunction in other parts of the gut. A better understanding of the relationship of this disorder to other animal health disorders is needed.

Abdominal Subcutaneous Fat: A Favorable or Nonfunctional Fat Depot for Glucose Metabolism in Chinese Adults?

PubMed

Hou, Xuhong; Chen, Peizhu; Hu, Gang; Wei, Li; Jiao, Lei; Wang, Hongmei; Liang, Yebei; Bao, Yuqian; Jia, Weiping

2018-06-01

The objective of this study was to assess the associations of abdominal visceral and subcutaneous adipose tissue with blood glucose and beta-cell function. In this study, 11,223 participants without known diabetes were selected for this cross-sectional analysis. Visceral and subcutaneous fat area (VFA and SFA) were measured by magnetic resonance imaging. An oral glucose tolerance test was conducted, and beta-cell function was evaluated. Men had significantly larger VFA but smaller SFA than women. After controlling for age, linear regression showed that SFA was adversely associated with 0-minute, 30-minute, and 2-hour plasma glucose (PG) and early-, first- and second-phase disposition indices (DIs). After further adjustment for BMI and VFA, some associations of SFA with PG indices and DIs disappeared, while the other associations became significantly weaker in men (2-hour PG: 0.05 and DI 2nd : -0.05) or were reversed in women (0-minute, 30-minute, and 2-hour PG: from -0.07 to -0.04; DI 1st : 0.04, P < 0.05). After adjustment for age, BMI, and SFA, VFA was significantly and adversely associated with PG indices and DIs, with the largest standardized regression coefficients with 2-hour PG. The associations of SFA with blood glucose and beta-cell function were clinically insignificant in Chinese adults. VFA had the strongest association with 2-hour PG. © 2018 The Obesity Society.

Visceral adiposity is significantly associated with type 2 diabetes in middle-aged and elderly Chinese women: A cross-sectional study.

PubMed

Lv, Xiaofei; Zhou, Weiwei; Sun, Jichao; Lin, Ruhai; Ding, Lin; Xu, Min; Xu, Yu; Zhao, Zhiyun; Chen, Yuhong; Bi, Yufang; Lu, Jieli; Wang, Weiqing; Ning, Guang

2017-10-01

Previous studies suggest that visceral fat is associated with type 2 diabetes (T2D) independent of body mass index (BMI). However, epidemiological data about the relationship between visceral fat and T2D are rare in Chinese. The aim of the present study was to investigate whether visceral fat area (VFA) is associated with T2D beyond and above BMI in the Chinese population. The present community-based cross-sectional study was conducted in 2013 on 4126 individuals (2545 women, 1581 men) aged ≥ 40 years, with T2D diagnosed according to 1999 World Health Organization criteria. The VFA was measured by a fat area analyzer using bioelectrical impedance analysis. Participants were categorized into normal weight and overweight/obese groups according to BMI. Within each group, compared with women with below-median VFA, women with above-median VFA had a significantly increased risk of diabetes (odds ratio [OR] 1.88, 95% confidence interval [CI] 1.31-2.69 in the normal weight group; OR 2.10, 95% CI 1.54-2.85 in the overweight/obese group), whereas among men the corresponding associations were not significant in either group. Among women, after multivariable adjustment including BMI, each one standard deviation increase in VFA was significantly associated with a 45% higher risk of having T2D (OR 1.45, 95% CI 1.26-1.67), whereas among men BMI, not VFA, was independently associated with T2D (OR 1.18, 95% CI 1.02-1.37). Visceral fat was independently associated with T2D in women regardless of obesity status, whereas in men BMI may have a more important effect on T2D than visceral fat. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Abdominal subcutaneous adipose tissue: a favorable adipose depot for diabetes?

PubMed

Chen, Peizhu; Hou, Xuhong; Hu, Gang; Wei, Li; Jiao, Lei; Wang, Hongmei; Chen, Siyu; Wu, Jingzhu; Bao, Yuqian; Jia, Weiping

2018-06-26

Previous studies have documented that visceral adipose tissue is positively associated with the risk of diabetes. However, the association of subcutaneous adipose tissue with diabetes risk is still in dispute. We aimed to assess the associations between different adipose distributions and the risk of newly diagnosed diabetes in Chinese adults. The Shanghai Nicheng Cohort Study was conducted among Chinese adults aged 45-70 years. The baseline data of 12,137 participants were analyzed. Subcutaneous and visceral fat area (SFA and VFA) were measured by magnetic resonance imaging. Diabetes was newly diagnosed using a 75 g oral glucose tolerance test. The multivariable-adjusted odds ratios (OR) and 95% confidence intervals (CI) of newly diagnosed diabetes per 1-standard deviation increase in SFA and VFA were 1.29 (1.19-1.39) and 1.61 (1.49-1.74) in men, and 1.10 (1.03-1.18) and 1.56 (1.45-1.67) in women, respectively. However, the association between SFA and newly diagnosed diabetes disappeared in men and was reversed in women (OR 0.86 [95% CI, 0.78-0.94]) after additional adjustment for body mass index (BMI) and VFA. The positive association between VFA and newly diagnosed diabetes remained significant in both sexes after further adjustment for BMI and SFA. Areas under the receiver operating characteristic curve of newly diagnosed diabetes predicted by VFA (0.679 [95% CI, 0.659-0.699] for men and 0.707 [95% CI, 0.690-0.723] for women) were significantly larger than by the other adiposity indicators. SFA was beneficial for lower risk of newly diagnosed diabetes in women but was not associated with newly diagnosed diabetes in men after taking general obesity and visceral obesity into account. VFA, however, was associated with likelihood of newly diagnosed diabetes in both Chinese men and women.

Association between visceral obesity and sarcopenia and vitamin D deficiency in older Koreans: the Ansan Geriatric Study.

PubMed

Seo, Ji A; Cho, Hyunjoo; Eun, Chai R; Yoo, Hye J; Kim, Sin G; Choi, Kyung M; Baik, Sei H; Choi, Dong S; Park, Moon H; Han, Changsu; Kim, Nan H

2012-04-01

To investigate whether vitamin D levels are independently associated with visceral obesity, sarcopenia, or sarcopenic obesity. Cross-sectional. Population-based sample of elderly adults living in Ansan, Korea. Two hundred sixteen men and 268 women aged 65 and older. Serum 25-hydroxyvitamin D (25(OH)D) levels, visceral fat area (VFA) according to abdominal computed tomography scanning, and body composition (body fat percentage, appendicular skeletal muscle mass (ASM)) using dual-energy X-ray absorptiometry. Visceral obesity was defined as VFA of 100 cm(2) or greater and sarcopenia as ASM/height(2) more than 1 standard deviation (SD) below the sex-specific mean of a young reference group. The adjusted 25(OH)D level for men was negatively associated with systolic blood pressure, VFA, and body fat percentage but positively associated with ASM. In women, waist circumference, triglyceride levels, and VFA were negatively correlated with 25(OH)D levels. In the joint regression model, VFA and ASM were independently associated with 25(OH)D levels (β = -0.078, P = .01 and β = 0.087, P = .02, respectively) per 1SD difference in VFA and ASM in men but not women. When participants were categorized according to four visceral obesity and sarcopenia categories, adjusted mean 25(OH)D level was lower in men with visceral obesity than in men without but was not affected by the presence or absence of sarcopenia. Greater visceral fat and lower muscle mass were associated with lower 25(OH)D levels in elderly Korean men, suggesting that screening for vitamin D deficiency may be appropriate in older Koreans with visceral obesity or sarcopenia. Sarcopenic obesity as defined according to prespecified criteria did not have an additive association with 25(OH)D levels. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

Characteristics of dairy cows with a greater or lower risk of subacute ruminal acidosis: Volatile fatty acid absorption, rumen digestion, and expression of genes in rumen epithelial cells.

PubMed

Gao, X; Oba, M

2016-11-01

The objective of this study was to examine whether lactating dairy cows with a greater or lower risk of subacute ruminal acidosis (SARA) have differences in volatile fatty acid (VFA) absorption rate, expression of genes involved in VFA metabolism and intracellular pH regulation in rumen epithelial cells, and in situ carbohydrate digestibility in the rumen. We fed 14 ruminally cannulated mid-lactating dairy cows (119±47.2d in milk; body weight 640±47.9kg) a high-grain diet consisting of 30% forage ad libitum, with an 18-d diet adaptation and a 7-d sample and data collection period. Eight cows with the lowest acidosis index [area below pH 5.8 normalized for dry matter intake (DMI); 0.10±0.16 pH × min/kg of DMI] and 5 with the highest acidosis index (3.72±0.19 pH × min/kg of DMI) were classified as animals with lower risk (LS) and higher risk (HS) of SARA, respectively. Minimum (5.75 vs. 5.33) and mean rumen pH (6.33 vs. 5.98) were higher for LS than for HS cows. In addition, the duration and area of rumen pH below 5.8 was lower in LS cows (24.9 vs. 481min/d; 2.94 vs. 102 pH × min/d). Although DMI, milk yield, and milk component yields did not differ, milk fat concentration tended to be higher for LS cows than for HS cows (3.36 vs. 2.93%). However, we observed no difference in VFA absorption rate between LS and HS cows. In situ starch and neutral detergent fiber digestibility were not different between LS and HS cows, but the relative mRNA abundance of lanosterol synthase (LSS) was higher for LS cows than for HS cows. In addition, the mRNA abundance of hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) tended to be higher for LS cows than for HS cows. These results suggested that VFA absorption rate might not explain the difference in rumen pH between LS and HS cows in the current study, even though expression of some genes related to VFA metabolism in rumen epithelium may be associated with variation in the risk of SARA among lactating cows. This variation in the risk of SARA may not be attributed to differences in the capacity of rumen microbes to ferment carbohydrates, because in situ carbohydrate digestibility in the rumen was not different between cows with higher and lower risk of SARA. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Cross-sectional and longitudinal study of association between circulating thiobarbituric acid-reacting substance levels and clinicobiochemical parameters in 1,178 middle-aged Japanese men - the Amagasaki Visceral Fat Study

PubMed Central

2011-01-01

Background Circulating thiobarbituric acid-reacting substance (TBARS) levels, a marker of systemic oxidative stress, are predictive of cardiovascular events. However, they has not been evaluated in Japanese, especially with regard to the factors that contribute to the changes in circulating TBARS levels. We investigated the cross-sectional and longitudinal relationships between circulating TBARS levels and various clinicobiochemical parameters in middle-aged men. Methods In this population-based study (The Amagasaki Visceral Fat Study), 1,178 Japanese male urban workers who had undergone health check-ups in 2006, 2007 and 2008 and were not on medications for metabolic disorders during the follow-up period, were enrolled. Serum TBARS levels were measured by the method of Yagi. The estimated visceral fat area (eVFA) by bioelectrical impedance was measured annually. After health check-ups, subjects received health education with lifestyle modification by medical personnel. Results The number of cardiovascular risk factors (hypertension, hyperglycemia, low HDL-C, hypertriglyceridemia, hyperuricemia, hyper-LDL-C and impaired renal function) augmented with the increases in log-eVFA (p < 0.0001) and log-TBARS (p < 0.0001). The combination of TBARS and eVFA had a multiplicative effect on risk factor accumulation (F value = 79.1, p = 0.0065). Stepwise multiple regression analysis identified log-eVFA, as well as age, log-body mass index (BMI), LDL-C, log-adiponectin, γ-glutamyl transpeptidase (γ-GTP) and uric acid as significant determinants of log-TBARS. Stepwise multiple regression analysis identified one-year changes in eVFA as well as BMI, γ-GTP and estimated glomerular filtration rate (eGFR) as significant determinants of one-year change in TBARS, and biennial changes in eVFA as well as BMI and γ-GTP, eGFR as significant determinants of biennial change in TBARS. Conclusions The present study showed a significant cross-sectional and longitudinal correlation between TBARS and eVFA, as well as BMI and γ- GTP, eGFR. Visceral fat reduction may independently associate with the improvement in systemic ROS in middle-aged Japanese men. Trial Registration The Amagasaki Visceral Fat Study UMIN000002391. PMID:22108213

Treatment of spent wash in anaerobic mesophilic suspended growth reactor (AMSGR).

PubMed

Banu, J Rajesh; Kaliappan, S; Rajkumar, M; Beck, Dieter

2006-01-01

Approximately 400 KL of spent wash or vinasse per annum is generated at an average COD concentration of 100,000 mg/l, by over 250 distilleries in India. There is an urgent need to develop, assess and use ecofriendly methods for the disposal of this high strength wastewater. Therefore, an attempt was made to investigate a few aspects of anaerobic digestion of spent wash collected from a distillery. The study was carried out in a 4 L laboratory scale anaerobic mesophilic suspended growth reactor. After the successful startup, the organic loading was increased stepwise to assess the performance of the reactor. During the study period, biogas generated was recorded and the maximum gas generated was found to be 16.9 L at an Organic Loading Rate (OLR) of 38 g COD/L. A 500% increase in the Volatile Fatty Acid (VFA) concentration (2150 mg/L) was observed, when the OLR was increased from 38 to 39 g COD/L. During the souring phase the removal of COD, Total Solids (TS) and Volatile Solids (VS) were in the order of 52%, 40% and 46% respectively. The methane content in the biogas varied from 65% to 75%.

Current practice and perspectives in CRO oversight based on a survey performed among members of the German Association of Research-Based Pharmaceutical Companies (vfa)

PubMed Central

Hennig, Michael; Hundt, Ferdinand; Busta, Susanne; Mikus, Stefan; Sanden, Per-Holger; Sörgel, Andrea; Ruppert, Thorsten

2017-01-01

In recent years, the number and scope of outsourced activities in the pharmaceutical industry have increased heavily. In addition, also the type of outsourcing has changed significantly in that time. This raises the question of whether and how sponsors retain the capability to select and to control the contract research organizations (CROs) involved and what expertise still has to be present in the development department as well as other relevant departments to ensure adequate oversight, also in line with the expectations of regulators and health authorities. In order to answer these questions, a survey was conducted among the German vfa member companies. The survey describes the latest developments and experiences in outsourcing by 18 German vfa member companies. It concentrates on measures how to implement Quality Assurance (QA) when performing outsourced clinical studies. This study shows that the majority of companies apply a full-outsourcing, preferred-provider model of clinical trial services, with the clinical research department playing the major role in this process. A large amount of guiding documents, processes and tools are used to ensure an adequate oversight of the services performed by the CRO(s). Finally the guiding principles for all oversight processes should be transparent communication, a clearly established expectation for quality, a precise definition of accountability and responsibility while avoiding silo mentality, and a comprehensive documentation of the oversight’s evidence. For globally acting and outsourcing sponsors, oversight processes need to be aligned with regards to local and global perspectives. This survey shows that the current implementation of oversight processes in the participating companies covers all relevant areas to ensure highest quality and integrity of the data produced by the outsourced clinical trial. PMID:28163667

Current practice and perspectives in CRO oversight based on a survey performed among members of the German Association of Research-Based Pharmaceutical Companies (vfa).

PubMed

Hennig, Michael; Hundt, Ferdinand; Busta, Susanne; Mikus, Stefan; Sanden, Per-Holger; Sörgel, Andrea; Ruppert, Thorsten

2017-01-01

In recent years, the number and scope of outsourced activities in the pharmaceutical industry have increased heavily. In addition, also the type of outsourcing has changed significantly in that time. This raises the question of whether and how sponsors retain the capability to select and to control the contract research organizations (CROs) involved and what expertise still has to be present in the development department as well as other relevant departments to ensure adequate oversight, also in line with the expectations of regulators and health authorities. In order to answer these questions, a survey was conducted among the German vfa member companies. The survey describes the latest developments and experiences in outsourcing by 18 German vfa member companies. It concentrates on measures how to implement Quality Assurance (QA) when performing outsourced clinical studies. This study shows that the majority of companies apply a full-outsourcing, preferred-provider model of clinical trial services, with the clinical research department playing the major role in this process. A large amount of guiding documents, processes and tools are used to ensure an adequate oversight of the services performed by the CRO(s). Finally the guiding principles for all oversight processes should be transparent communication, a clearly established expectation for quality, a precise definition of accountability and responsibility while avoiding silo mentality, and a comprehensive documentation of the oversight's evidence. For globally acting and outsourcing sponsors, oversight processes need to be aligned with regards to local and global perspectives. This survey shows that the current implementation of oversight processes in the participating companies covers all relevant areas to ensure highest quality and integrity of the data produced by the outsourced clinical trial.

Effects of fescue toxicosis induced by endophyte-infected tall fescue seed on forestomach epithelial gene expression in Angus steers

USDA-ARS?s Scientific Manuscript database

A previous report demonstrated that steers exposed to an endophyte-infected tall fescue seed extract had altered rumen epithelial blood flow and decreased ruminal flux of VFA. Thus, this study was conducted to determine whether there are differences in gene expression related to VFA absorption betwe...

Effects on the equine colon ecosystem of grass silage and haylage diets after an abrupt change from hay.

PubMed

Muhonen, S; Julliand, V; Lindberg, J E; Bertilsson, J; Jansson, A

2009-07-01

The objective of this study was to investigate the effect of an abrupt change from grass hay (81% DM) to grass silage (36% DM) or grass haylage (55% DM), fed at similar DM intakes, and to compare the effects of silage and haylage on the composition and activities of the colon microflora. The forages were from the same swath harvested on the same day. Four adult colon-fistulated geldings were randomly assigned to diets in a crossover design. The study started with a preperiod when all 4 horses received the hay diet, followed by an abrupt feed change to the haylage diet for 2 horses and the silage diet for 2 horses. All 4 horses then had a new second preperiod of hay, followed by an abrupt feed change to the opposite haylage and silage diet. The periods were 21 d long, and the forage-only diets were supplemented with minerals and salt. The abrupt feed changes were made at 0800 h. Colon samples were taken before the abrupt feed change, 4 and 28 h after the feed change, and 8, 15, and 21 d after the feed change, all at 1200 h. Colon bacterial counts, VFA, pH, and DM concentrations were unchanged throughout the first 28 h after the abrupt feed change from hay to haylage and silage. Also, fecal pH and DM concentrations were unchanged during the first 28 h. During the weekly observations, colon lactobacilli counts increased (P = 0.023) in horses receiving the silage diet and were greater than on the haylage diet at 21 d. Streptococci counts decreased (P = 0.046) in horses receiving the haylage diet and were less than on the silage diet at 15 and 21 d. Total VFA concentrations and colon and fecal pH did not differ between diets and were unchanged throughout the weekly observations. The DM concentration of colon digesta and feces decreased (P = 0.030 and 0.049, respectively) on both diets during the weekly observations. The results suggest that in horses fed at the maintenance level of energy intake, an abrupt feed change from grass hay to grass silage or grass haylage from the same crop does not induce any major alterations in the colon ecosystem during the first 28 h. During the subsequent 3-wk period, colon and fecal DM decreased and there were alterations in the lactobacilli and streptococci bacterial counts. The changes in lactobacilli and streptococci counts need further investigation.

Comprehensive monitoring and management of a long-term thermophilic CSTR treating coffee grounds, coffee liquid, milk waste, and municipal sludge.

PubMed

Shofie, Mohammad; Qiao, Wei; Li, Qian; Takayanagi, Kazuyuki; Li, Yu-You

2015-09-01

The CSTR process has previously not been successfully applied to treat coffee residues under thermophilic temperature and long term operation. In this experiment, the CSTR was fed with mixture substrate (TS ∼ 70 g/L) of coffee grounds, coffee wastewater, milk waste and municipal sludge and it was operated under 55 °C for 225 days. A steady state was achieved under HRT 30 days and OLR 4.0 kg-COD/m(3)/d. However, there was an 35 days inhibition with VFA accumulation (propionic acid 700-1900 mg/L) when doubling the OLR by shortening HRT to 15 days. But, an addition of microelements and sulfate (0.5 g/L) in feedstock increased reactor resilience and stability under high loading rate and propionic acid stress. Continuous monitoring of hydrogen in biogas indicated the imbalance of acetogenesis. The effectiveness of comprehensive parameters (total VFA, propionic acid, IA/PA, IA/TA and CH4 content) was proved to manage the thermophilic system. Copyright © 2015 Elsevier Ltd. All rights reserved.

High-solid Anaerobic Co-digestion of Sewage Sludge and Cattle Manure: The Effects of Volatile Solid Ratio and pH

PubMed Central

Dai, Xiaohu; Chen, Yang; Zhang, Dong; Yi, Jing

2016-01-01

High-solid anaerobic digestion is an attractive solution to the problem of sewage sludge disposal. One method that can be used to enhance the production of volatile fatty acids (VFAs) and the generation of methane from anaerobic digestion involves combining an alkaline pretreatment step with the synergistic effects of sewage sludge and cattle manure co-digestion, which improves the activity of key enzymes and microorganisms in the anaerobic co-digestion system to promote the digestion of organic waste. In this study, we describe an efficient strategy that involves adjusting the volatile solid (VS) ratio (sewage sludge/cattle manure: 3/7) and initial pH (9.0) to improve VFA production and methane generation from the co-digestion of sludge and manure. The experimental results indicate that the maximum VFA production was 98.33 g/kg-TS (total solid) at the optimal conditions. Furthermore, methane generation in a long-term semi-continuously operated reactor (at a VS ratio of 3/7 and pH of 9.0) was greater than 120.0 L/kg-TS. PMID:27725704

Slice profile effects in 2D slice-selective MRI of hyperpolarized nuclei.

PubMed

Deppe, Martin H; Teh, Kevin; Parra-Robles, Juan; Lee, Kuan J; Wild, Jim M

2010-02-01

This work explores slice profile effects in 2D slice-selective gradient-echo MRI of hyperpolarized nuclei. Two different sequences were investigated: a Spoiled Gradient Echo sequence with variable flip angle (SPGR-VFA) and a balanced Steady-State Free Precession (SSFP) sequence. It is shown that in SPGR-VFA the distribution of flip angles across the slice present in any realistically shaped radiofrequency (RF) pulse leads to large excess signal from the slice edges in later RF views, which results in an undesired non-constant total transverse magnetization, potentially exceeding the initial value by almost 300% for the last RF pulse. A method to reduce this unwanted effect is demonstrated, based on dynamic scaling of the slice selection gradient. SSFP sequences with small to moderate flip angles (<40 degrees ) are also shown to preserve the slice profile better than the most commonly used SPGR sequence with constant flip angle (SPGR-CFA). For higher flip angles, the slice profile in SSFP evolves in a manner similar to SPGR-CFA, with depletion of polarization in the center of the slice. Copyright 2009 Elsevier Inc. All rights reserved.

High-solid Anaerobic Co-digestion of Sewage Sludge and Cattle Manure: The Effects of Volatile Solid Ratio and pH

NASA Astrophysics Data System (ADS)

Dai, Xiaohu; Chen, Yang; Zhang, Dong; Yi, Jing

2016-10-01

High-solid anaerobic digestion is an attractive solution to the problem of sewage sludge disposal. One method that can be used to enhance the production of volatile fatty acids (VFAs) and the generation of methane from anaerobic digestion involves combining an alkaline pretreatment step with the synergistic effects of sewage sludge and cattle manure co-digestion, which improves the activity of key enzymes and microorganisms in the anaerobic co-digestion system to promote the digestion of organic waste. In this study, we describe an efficient strategy that involves adjusting the volatile solid (VS) ratio (sewage sludge/cattle manure: 3/7) and initial pH (9.0) to improve VFA production and methane generation from the co-digestion of sludge and manure. The experimental results indicate that the maximum VFA production was 98.33 g/kg-TS (total solid) at the optimal conditions. Furthermore, methane generation in a long-term semi-continuously operated reactor (at a VS ratio of 3/7 and pH of 9.0) was greater than 120.0 L/kg-TS.

Production of co-polymers of polyhydroxyalkanoates by regulating the hydrolysis of biowastes.

PubMed

Kumar, Prasun; Ray, Subhasree; Kalia, Vipin C

2016-01-01

Production of polyhydroxyalkanoate (PHA) co-polymers by Bacillus spp. was studied by feeding defined volatile fatty acids (VFAs) obtained through controlled hydrolysis of various wastes. Eleven mixed hydrolytic cultures (MHCs) each containing 6 strains could generate VFA from slurries of (2% total solids): pea-shells (PS), potato peels (PP), apple pomace (AP) and onion peels (OP). PS hydrolysates (obtained with MHC2 and MHC5) inoculated with Bacillus cereus EGU43 and Bacillus thuringiensis EGU45 produced co-polymers of PHA at the rate of 15-60mg/L with a 3HV content of 1%w/w. An enhancement in PHA yield of 3.66-fold, i.e. 205-550mg/L with 3HV content up to 7.5%(w/w) was observed upon addition of OP hydrolysate and 1% glucose (w/v) to PS hydrolysates. This is the first demonstration, where PHA co-polymer composition, under non-axenic conditions, could be controlled by customizing VFA profile of the hydrolysate by the addition of different biowastes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Full-scale production of VFAs from sewage sludge by anaerobic alkaline fermentation to improve biological nutrients removal in domestic wastewater.

PubMed

Liu, He; Han, Peng; Liu, Hongbo; Zhou, Guangjie; Fu, Bo; Zheng, Zhiyong

2018-07-01

A full-scale project of thermal-alkaline pretreatment and alkaline fermentation of sewage sludge was built to produce volatile fatty acids (VFAs) which was then used as external carbon source for improving biological nitrogen and phosphorus removals (BNPR) in wastewater plant. Results showed this project had efficient and stable performances in VFA production, sludge reduce and BNPR. Hydrolysis rate in pretreatment, VFAs yield in fermentation and total VS reduction reached 68.7%, 261.32 mg COD/g VSS and 54.19%, respectively. Moreover, fermentation liquid with VFA presented similar efficiency as acetic acid in enhancing BNPR, obtaining removal efficiencies of nitrogen and phosphorus up to 72.39% and 89.65%, respectively. Finally, the project also presented greater economic advantage than traditional processes, and the net profits for VFAs and biogas productions are 9.12 and 3.71 USD/m 3 sludge, respectively. Long-term operation indicated that anaerobic alkaline fermentation for VFAs production is technically and economically feasible for sludge carbon recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

Efficiency and rumen responses in younger and older Holstein heifers limit-fed diets of differing energy density.

PubMed

Zanton, G I; Heinrichs, A J

2016-04-01

The objective of this study was to evaluate the effects of limit feeding diets of different predicted energy density on the efficiency of utilization of feed and nitrogen and rumen responses in younger and older Holstein heifers. Eight rumen-cannulated Holstein heifers (4 heifers beginning at 257 ± 7 d, hereafter "young," and 4 heifers beginning at 610 ± 16 d, hereafter "old") were limit-fed high [HED; 2.64 Mcal/kg of dry matter (DM), 15.31% crude protein (CP)] or low (LED; 2.42 Mcal/kg of DM, 14.15% CP) energy density diets according to a 4-period, split-plot Latin square design with 28-d periods. Diets were limit-fed to provide isonitrogenous and isoenergetic intake on a rumen empty body weight (BW) basis at a level predicted to support approximately 800 g/d of average daily gain. During the last 7d of each period, rumen contents were subsampled over a 24-h period, rumen contents were completely evacuated, and total collection of feces and urine was made over 4d. Intakes of DM and water were greater for heifers fed LED, although, by design, calculated intake of metabolizable energy did not differ between age groups or diets when expressed relative to rumen empty BW. Rumen pH was lower, ammonia (NH3-N) concentration tended to be higher, and volatile fatty acids (VFA) concentration was not different for HED compared with LED and was unaffected by age group. Rumen content mass was greater for heifers fed LED and for old heifers, so when expressing rumen fermentation responses corrected for this difference in pool size, NH3-N pool size was not different between diets and total moles of VFA in the rumen were greater for heifers fed LED, whereas these pool sizes were greater for old heifers. Total-tract digestibility of potentially digestible neutral detergent fiber (NDF) was greater in heifers fed LED and for young heifers, whereas the fractional rate of ruminal passage and digestion of NDF were both greater in heifers fed LED. Digestibility of N was greater for heifers fed HED, but was unaffected by age group, whereas the efficiency of N retention was greater for heifers fed HED and for young heifers. Manure output was reduced in heifers fed HED, but the effect was largest in old heifers. Results confirm previous studies in which young heifers utilize N more efficiently than old heifers, primarily through greater efficiency of postabsorptive metabolism. Results also support the concept of limit feeding HED diets as a potential means to reduce manure excretion and increase nitrogen efficiency. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Impact of feed restriction and housing hygiene conditions on specific and inflammatory immune response, the cecal bacterial community and the survival of young rabbits.

PubMed

Combes, S; Massip, K; Martin, O; Furbeyre, H; Cauquil, L; Pascal, G; Bouchez, O; Le Floc'h, N; Zemb, O; Oswald, I P; Gidenne, T

2017-05-01

Limiting the post-weaning intake of the young rabbit is known to improve its resistance to digestive disorders, whereas a degradation of its housing hygiene is assumed to have a negative impact on its health. This study aims at providing insights into the mechanism of digestive health preservation regarding both host (growth and immune response) and its symbiotic digestive microbiota. A 2×2 factorial design from weaning (day 28) to day 64 was set up: ad libitum intake or restricted intake at 70% of ad libitum, and high v. low hygiene of housing (n=105 per group). At day 36 and day 45, 15 animals/group were subcutaneously immunized with ovalbumin (OVA) to assess their specific immune response. Blood was sampled at 36, 45, 57 and 64 days of age to determine total and anti-OVA immunoglobulin type G (IgG) and haptoglobin levels. The cecal bacterial community was explored (18 per group) by 454 pyrosequencing of genes coding for the 16S ribosomal RNA, whereas cecal pH, NH3 and volatile fatty acid (VFA) concentrations were measured to characterize fermentative activity. A 30% reduction in feed intake reduced the growth by only 17% (P<0.001), and improved the feed conversion ratio by 15% (P<0.001), whereas the degradation of hygiene conditions slightly decreased the feed intake in ad libitum fed rabbits (-3.5%, P<0.02). As poor hygiene conditions did not affect weight gain, feed conversion was improved from day 42 (P<0.05). Restricted feeding led to a lower mortality between day 28 and day 40 (P=0.047), whereas degraded hygiene conditions decreased overall morbidity (7.8% v. 16.6%; P<0.01). Both a reduced intake and low hygiene conditions of housing affected microbiota composition and especially dominant genera belonging to the Ruminococcaceae family (P<0.01). Moreover, low hygiene was associated with a higher Ruminococcaceae/Lachnospiraceae ratio (3.7 v. 2.4; P<0.05). Cecal total VFA and pH were increased (+19%; P<0.001) and decreased (-0.1 pH unit; P<0.05), respectively, in feed-restricted rabbits. Neither specific anti-OVA IgG nor haptoglobin was affected by treatments. Total IgG concentrations were the highest in animals raised in poor hygiene conditions after 8 days of restriction, but decreased after 19 days of restriction in high hygiene conditions (-2.15%; P<0.05). In conclusion, the degradation of hygiene conditions failed to induce a systematic specific and inflammatory response in rabbit, but reduced morbidity instead. Our results suggest that the microbiota composition would be a helpful source of biomarkers of digestive health.

Enhancement of volatile fatty acid production by co-fermentation of food waste and excess sludge without pH control: The mechanism and microbial community analyses.

PubMed

Wu, Qing-Lian; Guo, Wan-Qian; Zheng, He-Shan; Luo, Hai-Chao; Feng, Xiao-Chi; Yin, Ren-Li; Ren, Nan-Qi

2016-09-01

The study provided a cost-effective and high-efficiency volatile fatty acid (VFA) production strategy by co-fermentation of food waste (FW) and excess sludge (ES) without artificial pH control. VFA production of 867.42mg COD/g-VS was obtained under the optimized condition: FW/ES 5, solid retention time 7d, organic loading rate 9g VS/L-d and temperature 40°C. Mechanism exploration revealed that the holistic biodegradability of substrate was greatly enhanced, and proper pH range (5.2-6.4) was formed by the high buffering capacity of the co-fermentation system itself, which effectively enhanced hydrolysis yield (63.04%) and acidification yield (83.46%) and inhibited methanogenesis. Moreover, microbial community analysis manifested that co-fermentation raised the relative abundances of hydrolytic and acidogenic bacteria including Clostridium, Sporanaerobacter, Tissierella and Bacillus, but suppressed the methanogen Anaerolineae, which also facilitated high VFA production. These results were of great guiding significance aiming for VFA recovery from FW and ES in large-scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydrolytic and acidogenic fermentation potential of food waste with source segregated feces-without-urine as co-substrate.

PubMed

Rajagopal, Rajinikanth; Ahamed, Ashiq; Wang, Jing-Yuan

2014-09-01

This study explored a new approach to enhance VFA productivity from anaerobic co-digestion of food-waste (FW) with source-segregated brown-water (BW) [feces-without-urine]. Effort was made to separate urine and BW from the source (using no-mix-toilet) mainly to expedite further treatment and resource-recovery. Effect of alkaline-pH [B] and acclimatized acidogenic inoculum [C] on acidification efficiency was investigated and compared with raw FW+BW co-digestion [A]. Batch-assay results indicated that VFA productivity persists for 144-h with about 615%, 522% and 376% increase in VFA-COD, respectively for 3-conditions [A-C]; which accounted for 70%, 49% and 58% of CODs input, respectively. High butyric-acid was observed in [A] and [C], followed by acetic, propionic-acids; whereas, abundant acetic-acid (86% of TVFA) was observed in [B], which are the most favorable-forms for methane production or other value-added-products. For 144-h of acidification, this study validated the feasibility of maximizing VFA-yield by 7-12 times compared to FW or BW as a sole-substrate. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hydrolysis and volatile fatty acids accumulation of waste activated sludge enhanced by the combined use of nitrite and alkaline pH.

PubMed

Huang, Cheng; Liu, Congcong; Sun, Xiuyun; Sun, Yinglu; Li, Rui; Li, Jiansheng; Shen, Jinyou; Han, Weiqing; Liu, Xiaodong; Wang, Lianjun

2015-12-01

Volatile fatty acids (VFAs) production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow hydrolysis and/or poor substrate availability. Increased attention has been given to enhance the hydrolysis and acidification of WAS recently. This study presented an efficient and green strategy based on the combined use of nitrite pretreatment and alkaline pH to stimulate hydrolysis and VFA accumulation from WAS. Results showed that both proteins and polysaccharides increased in the presence of nitrite, indicating the enhancement of sludge solubilization and hydrolysis processes. Mechanism investigations showed that nitrite pretreatment could disintegrate the sludge particle and disperse extracellular polymeric substances (EPS). Then, anaerobic digestion tests demonstrated VFA production increased with nitrite treatment. The maximal VFA accumulation was achieved with 0.1 g N/L nitrite dosage and pH 10.0 at a sludge retention time (SRT) of 7 days, which was much higher VFA production in comparison with the blank, sole nitrite pretreatment, or sole pH 10. The potential analysis suggested that the combined nitrite pretreatment and alkaline pH is capable of enhancing WAS digestion with a great benefit for biological nutrient removal (BNR).

Evaluation of the nutritional value of locally produced forage in Korea using chemical analysis and in vitro ruminal fermentation.

PubMed

Ki, Kwang Seok; Park, Su Bum; Lim, Dong Hyun; Seo, Seongwon

2017-03-01

The use of locally produced forage (LPF) in cattle production has economic and environmental advantages over imported forage. The objective of this study was to characterize the nutritional value of LPF commonly used in Korea. Differences in ruminal fermentation characteristics were also examined for the LPF species commonly produced from two major production regions: Chungcheong and Jeolla. Ten LPF (five from each of the two regions) and six of the most widely used imported forages originating from North America were obtained at least three times throughout a year. Each forage species was pooled and analyzed for nutrient content using detailed chemical analysis. Ruminal fermentation characteristics were also determined by in vitro anaerobic incubations using strained rumen fluid for 0, 3, 6, 12, 24, and 48 h. At each incubation time, total gas, pH, ammonia, volatile fatty acid (VFA) concentrations, and neutral detergent fiber digestibility were measured. By fitting an exponential model, gas production kinetics were obtained. Significant differences were found in the non-fiber carbohydrate (NFC) content among the forage species and the regions (p<0.01). No nutrient, other than NFC, showed significant differences among the regions. Crude protein, NFC, and acid detergent lignin significantly differed by forage species. The amount of acid detergent insoluble protein tended to differ among the forages. The forages produced in Chungcheong had a higher amount of NFC than that in Jeolla (p<0.05). There were differences in ruminal fermentation of LPF between the two regions and interactions between regions and forage species were also significant (p<0.05). The pH following a 48-h ruminal fermentation was lower in the forages from Chungcheong than from Jeolla (p<0.01), and total VFA concentration was higher in Chungcheong than in Jeolla (p = 0.05). This implies that fermentation was more active with the forages from Chungcheong than from Jeolla. Analysis of gas production profiles showed the rate of fermentation differed among forage species (p<0.05). The results of the present study showed that the nutritional values of some LPF (i.e., corn silage and Italian ryegrass) are comparable to those of imported forages widely used in Korea. This study also indicated that the nutritional value of LPF differs by origin, as well as by forage species. Detailed analyses of nutrient composition and digestion kinetics of LPF should be routinely employed to evaluate the correct nutritional value of LPF and to increase their use in the field.

Evaluation of the nutritional value of locally produced forage in Korea using chemical analysis and in vitro ruminal fermentation

PubMed Central

Ki, Kwang Seok; Park, Su Bum; Lim, Dong Hyun; Seo, Seongwon

2017-01-01

Objective The use of locally produced forage (LPF) in cattle production has economic and environmental advantages over imported forage. The objective of this study was to characterize the nutritional value of LPF commonly used in Korea. Differences in ruminal fermentation characteristics were also examined for the LPF species commonly produced from two major production regions: Chungcheong and Jeolla. Methods Ten LPF (five from each of the two regions) and six of the most widely used imported forages originating from North America were obtained at least three times throughout a year. Each forage species was pooled and analyzed for nutrient content using detailed chemical analysis. Ruminal fermentation characteristics were also determined by in vitro anaerobic incubations using strained rumen fluid for 0, 3, 6, 12, 24, and 48 h. At each incubation time, total gas, pH, ammonia, volatile fatty acid (VFA) concentrations, and neutral detergent fiber digestibility were measured. By fitting an exponential model, gas production kinetics were obtained. Results Significant differences were found in the non-fiber carbohydrate (NFC) content among the forage species and the regions (p<0.01). No nutrient, other than NFC, showed significant differences among the regions. Crude protein, NFC, and acid detergent lignin significantly differed by forage species. The amount of acid detergent insoluble protein tended to differ among the forages. The forages produced in Chungcheong had a higher amount of NFC than that in Jeolla (p<0.05). There were differences in ruminal fermentation of LPF between the two regions and interactions between regions and forage species were also significant (p<0.05). The pH following a 48-h ruminal fermentation was lower in the forages from Chungcheong than from Jeolla (p<0.01), and total VFA concentration was higher in Chungcheong than in Jeolla (p = 0.05). This implies that fermentation was more active with the forages from Chungcheong than from Jeolla. Analysis of gas production profiles showed the rate of fermentation differed among forage species (p<0.05). Conclusion The results of the present study showed that the nutritional values of some LPF (i.e., corn silage and Italian ryegrass) are comparable to those of imported forages widely used in Korea. This study also indicated that the nutritional value of LPF differs by origin, as well as by forage species. Detailed analyses of nutrient composition and digestion kinetics of LPF should be routinely employed to evaluate the correct nutritional value of LPF and to increase their use in the field. PMID:28002936

Obstructive sleep apnea with excessive daytime sleepiness is associated with non-alcoholic fatty liver disease regardless of visceral fat

PubMed Central

Yu, Ji Hee; Ahn, Jae Hee; Yoo, Hye Jin; Seo, Ji A; Kim, Sin Gon; Choi, Kyung Mook; Baik, Sei Hyun; Choi, Dong Seop; Shin, Chol; Kim, Nan Hee

2015-01-01

Background/Aims: Obstructive sleep apnea (OSA) is associated with an increased risk of obesity and non-alcoholic fatty liver disease (NAFLD), but it remains unclear whether the risk of NAFLD is independently related to OSA regardless of visceral obesity. Thus, the aim of the present study was to examine whether OSA alone or in combination with excessive daytime sleepiness (EDS) or short sleep duration was associated with NAFLD independent of visceral fat in Korean adults. Methods: A total of 621 participants were selected from the Korean Genome and Epidemiology Study (KoGES). The abdominal visceral fat area (VFA) and hepatic fat components of the participants were assessed using computed tomography scans and they were then categorized into four groups depending on the presence of OSA and EDS. Results: The proportions of NAFLD were 21.1%, 18.5%, 32.4%, and 46.7% in participants without OSA/EDS, with only EDS, with only OSA, and with both OSA and EDS, respectively. A combination of OSA and EDS increased the odds ratio (OR) for developing NAFLD (OR, 2.75; 95% confidence interval [CI], 1.21 to 6.28) compared to those without OSA/EDS, and this association remained significant (OR, 2.38; 95% CI, 1.01 to 5.59) even after adjusting for VFA. In short sleepers (< 5 hours) with OSA, the adjusted OR for NAFLD was 2.50 (95% CI, 1.08 to 5.75) compared to those sleeping longer than 5 hours without OSA. Conclusions: In the present study, OSA was closely associated with NAFLD in Korean adults. This association was particularly strong in those with EDS or short sleep duration regardless of VFA. PMID:26552460

Simultaneous Hydrogen and Methane Production Through Multi-Phase Anaerobic Digestion of Paperboard Mill Wastewater Under Different Operating Conditions.

PubMed

Farghaly, Ahmed; Tawfik, Ahmed

2017-01-01

Multi-phase anaerobic reactor for H 2 and CH 4 production from paperboard mill wastewater was studied. The reactor was operated at hydraulic retention times (HRTs) of 12, 18, 24, and 36 h, and organic loading rates (OLRs) of 2.2, 1.5, 1.1, and 0.75 kg chemical oxygen demand (COD)/m 3  day, respectively. HRT of 12 h and OLR of 2.2 kg COD/m 3  day provided maximum hydrogen yield of 42.76 ± 14.5 ml/g COD removed and volumetric substrate uptake rate (-rS) of 16.51 ± 4.43 mg COD/L h. This corresponded to the highest soluble COD/total COD (SCOD/TCOD) ratio of 56.25 ± 3.3 % and the maximum volatile fatty acid (VFA) yield (Y VFA ) of 0.21 ± 0.03 g VFA/g COD, confirming that H 2 was mainly produced through SCOD conversion. The highest methane yield (18.78 ± 3.8 ml/g COD removed ) and -rS of 21.74 ± 1.34 mgCOD/L h were achieved at an HRT of 36 h and OLR of 0.75 kg COD/m 3  day. The maximum hydrogen production rate (HPR) and methane production rate (MPR) were achieved at carbon to nitrogen (C/N) ratio of 47.9 and 14.3, respectively. This implies the important effect of C/N ratio on the distinction between the dominant microorganism bioactivities responsible for H 2 and CH 4 production.

Bacterial communities in the rumen of Holstein heifers differ when fed orchardgrass as pasture vs. hay

PubMed Central

Mohammed, Riazuddin; Brink, Geoffrey E.; Stevenson, David M.; Neumann, Anthony P.; Beauchemin, Karen A.; Suen, Garret; Weimer, Paul J.

2014-01-01

The rich and diverse microbiota of the rumen provides ruminant animals the capacity to utilize highly fibrous feedstuffs as their energy source, but there is surprisingly little information on the composition of the microbiome of ruminants fed all-forage diets, despite the importance of such agricultural production systems worldwide. In three 28-day periods, three ruminally-cannulated Holstein heifers sequentially grazed orchardgrass pasture (OP), then were fed orchardgrass hay (OH), then returned to OP. These heifers displayed greater shifts in ruminal bacterial community composition (determined by automated ribosomal intergenic spacer analysis and by pyrotag sequencing of 16S rRNA genes) than did two other heifers maintained 84 d on the same OP. Phyla Firmicutes and Bacteroidetes dominated all ruminal samples, and quantitative PCR indicated that members of the genus Prevotella averaged 23% of the 16S rRNA gene copies, well below levels previously reported with cows fed total mixed rations. Differences in bacterial community composition and ruminal volatile fatty acid (VFA) profiles were observed between the OP and OH despite similarities in gross chemical composition. Compared to OP, feeding OH increased the molar proportion of ruminal acetate (P = 0.02) and decreased the proportion of ruminal butyrate (P < 0.01), branched-chain VFA (P < 0.01) and the relative population size of the abundant genus Butyrivibrio (P < 0.001), as determined by pyrotag sequencing. Despite the low numbers of animals examined, the observed changes in VFA profile in the rumens of heifers on OP vs. OH are consistent with the shifts in Butyrivibrio abundance and its known physiology as a butyrate producer that ferments both carbohydrates and proteins. PMID:25538699

Serum Glycated Albumin Is Inversely Influenced by Fat Mass and Visceral Adipose Tissue in Chinese with Normal Glucose Tolerance

PubMed Central

Hao, Yaping; Yang, Rong; Ni, Jie; Xiao, Yunfeng; Tang, Junling; Bao, Yuqian; Jia, Weiping

2012-01-01

Background Recent studies have revealed that body mass index (BMI) inversely influenced serum glycated albumin (GA), which may cause an underestimation of GA-monitored short-term hyperglycemic control. Objective This study was to investigate the association between anthropometric variables (BMI and waist circumference (W)) and accurate adiposity variables (percentage of body fat (%fat), fat mass, free fat mass (FFM), subcutaneous fat area (SFA), and visceral fat area (VFA)) with serum GA. Design A total of 2563 subjects (1037 men, 593 premenopausal women, and 933 postmenopausal women) with normal glucose tolerance underwent bioelectrical impedance body fat content measurement and magnetic resonance imaging. Serum GA and absolute value of GA (aGA) were measured by enzymatic assay. Results Compared to the BMI <25.0 kg/m2 group, the BMI ≥25.0 kg/m2 group had significantly higher fasting plasma glucose, glycated hemoglobin A1c, and body fat parameters including W, %fat, fat mass, FFM, SFA, and VFA, but significantly lower aGA, and GA in all the three sex- and menopause-stratified groups (all P<0.05). GA decreased with the increment of fat mass for all three groups (all P for trend <0.001). In the same BMI category, men and postmenopausal women with elevated %fat (men, ≥25%; women, ≥35%) still had significantly lower GA than those with normal %fat (men, <25%; women, <35%) (all P<0.05). Multiple stepwise regression showed that %fat, fat mass, and VFA were independently associated with GA. Conclusions Serum GA was inversely influenced by fat mass and visceral adipose tissue in Chinese with normal glucose tolerance. PMID:23209844

Obstructive sleep apnea with excessive daytime sleepiness is associated with non-alcoholic fatty liver disease regardless of visceral fat.

PubMed

Yu, Ji Hee; Ahn, Jae Hee; Yoo, Hye Jin; Seo, Ji A; Kim, Sin Gon; Choi, Kyung Mook; Baik, Sei Hyun; Choi, Dong Seop; Shin, Chol; Kim, Nan Hee

2015-11-01

Obstructive sleep apnea (OSA) is associated with an increased risk of obesity and non-alcoholic fatty liver disease (NAFLD), but it remains unclear whether the risk of NAFLD is independently related to OSA regardless of visceral obesity. Thus, the aim of the present study was to examine whether OSA alone or in combination with excessive daytime sleepiness (EDS) or short sleep duration was associated with NAFLD independent of visceral fat in Korean adults. A total of 621 participants were selected from the Korean Genome and Epidemiology Study (KoGES). The abdominal visceral fat area (VFA) and hepatic fat components of the participants were assessed using computed tomography scans and they were then categorized into four groups depending on the presence of OSA and EDS. The proportions of NAFLD were 21.1%, 18.5%, 32.4%, and 46.7% in participants without OSA/EDS, with only EDS, with only OSA, and with both OSA and EDS, respectively. A combination of OSA and EDS increased the odds ratio (OR) for developing NAFLD (OR, 2.75; 95% confidence interval [CI], 1.21 to 6.28) compared to those without OSA/EDS, and this association remained significant (OR, 2.38; 95% CI, 1.01 to 5.59) even after adjusting for VFA. In short sleepers (< 5 hours) with OSA, the adjusted OR for NAFLD was 2.50 (95% CI, 1.08 to 5.75) compared to those sleeping longer than 5 hours without OSA. In the present study, OSA was closely associated with NAFLD in Korean adults. This association was particularly strong in those with EDS or short sleep duration regardless of VFA.

Effects of addition of Aspergillus oryzae culture and 2-hydroxyl-4-(methylthio) butanoic acid on milk performance and rumen fermentation of dairy cows.

PubMed

Sun, Hua; Wu, Yueming; Wang, Yanming; Wang, Chong; Liu, Jianxin

2017-04-01

To investigate effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio) butanoic acid (HMB) on milk performance and rumen fermentation of dairy cows. Sixty-four multiparous Chinese Holstein cows were randomly allocated into four experimental diets: (i) Control diet; (ii) AOC diet: 5 g AOC/day per head; (iii) HMB diet: 25 g HMB/day; and (iv) AH diet: 5 g AOC plus 25 g HMB/day. Added HMB tended to increase the yield of milk protein (P = 0.06) and 3.5% fat-corrected milk (P = 0.08) and milk fat content (P = 0.09). Milk fat yield (P = 0.03) and the contents of milk protein (P = 0.05) were increased by adding HMB. The cows fed on AOC diet had a tendency for higher body weight (BW) gain (P = 0.08). Addition of AOC, HMB and AH increased content of microbial protein (MCP) and total volatile fatty acids (VFA) (P < 0.01) in rumen fluid. Populations of rumen fungi, Fibrobacter succinogenes and Ruminococcus flavefaciens relative to total bacterial 16S rDNA (P ≤ 0.03) and activity of carboxymethylcellulase (CMCase) (P < 0.01) were increased with added AOC or HMB. It is inferred that added AOC or HMB can increase the contents of MCP and total VFA potentially by stimulating rumen microbe populations and CMCase activity. © 2016 Japanese Society of Animal Science.

Performance and kinetic evaluation of semi-continuously fed anaerobic digesters treating food waste: role of trace elements.

PubMed

Zhang, Wanqin; Wu, Shubiao; Guo, Jianbin; Zhou, Jie; Dong, Renjie

2015-02-01

This study investigated the effects of trace elements (TEs) on the anaerobic digestion (AD) of food waste (FW) in laboratory-scale semi-continuously fed anaerobic digesters. The duration of digesters operation was approximately 400 days. Organic loading rates (OLRs) ranged from 1.0 to 5.5 g VS L(-1) d(-1) at 37 °C. Results showed that methane production of the digester was severely inhibited at a volatile fatty acid (VFA) concentration of 30,000 mg L(-1) at OLR of 4.0 g VS L(-1) d(-1) in the absence of TEs. Contrary to the failed digesters, a stable performance was achieved in the TEs added digesters. High methane yield (approximately 465.4 mL CH4 g(-1)VSadded) was obtained, and no significant accumulation of VFA was observed in the TEs added digesters at OLR of 1.0-5.0 g VS L(-1) d(-1) and HRT of 40 days. These findings strongly indicated that the addition of TEs has an important impact on the operation stability of AD of FW. Copyright © 2014 Elsevier Ltd. All rights reserved.

Application of the World Health Organization Fracture Risk Assessment Tool to predict need for dual-energy X-ray absorptiometry scanning in postmenopausal women.

PubMed

Chao, An-Shine; Chen, Fang-Ping; Lin, Yu-Ching; Huang, Ting-Shuo; Fan, Chih-Ming; Yu, Yu-Wei

2015-12-01

To evaluate the efficacy of the World Health Organization Fracture Risk Assessment Tool, excluding bone mineral density (pre-BMD FRAX), in identifying Taiwanese postmenopausal women needing dual-energy X-ray absorptiometry (DXA) examination for further treatment. The pre-BMD FRAX score was calculated for 231 postmenopausal women who participated in public health education workshops in the local Keelung community, Taiwan. DXA scanning and vertebral fracture assessment (VFA) were arranged for women classified as intermediate or high risk for fracture using the pre-BMD FRAX fracture probability. Pre-BMD FRAX classified 26 women as intermediate risk and 37 as having high risk for fracture. Subsequent DXA scans for these 63 women showed that 36 were osteoporotic, 19 were osteopenic, and eight had normal bone density. Concurrent VFA revealed 25 spine factures in which 14 were osteoporotic, seven were osteopenic, and four had normal bone density. The efficacy of the pre-BMD FRAX score to identify those patients with low bone mass by DXA was 87.3% (55/63). When VFA was combined with BMD to identify those patients with high risk (osteopenia, osteoporosis, or spinal fracture), the efficacy of the pre-BMD score increased to 93.7% (59/63). According to the National Osteoporosis Foundation, the overall concordance between pre-BMD FRAX and BMD, expressed through the kappa index, was 0.967. Compared with the evaluation when BMD was used alone, there was a significant increase in efficacy in identifying women who need treatment using BMD plus VFA or FRAX plus BMD. Furthermore, the highest efficacy was achieved when FRAX with BMD and VFA was used. The pre-BMD FRAX score not only efficiently predicts postmenopausal patients who are potentially at risk and might require treatment but also reduces unnecessary DXA use. Concurrent VFA during DXA use increases spine fracture detection. This improvement in diagnostic efficacy allows clinicians to provide the most appropriate therapeutic recommendation. Copyright © 2015. Published by Elsevier B.V.

Effects of a salivary stimulant, slaframine, on ruminal fermentation, bacterial protein synthesis and digestion in frequently fed steers.

PubMed

Froetschel, M A; Amos, H E; Evans, J J; Croom, W J; Hagler, W M

1989-03-01

Slaframine (SF), a parasympathomimetic salivary stimulant, was administered i.m. (10, 15 or 20 micrograms SF/kg BW) to ruminally and abomasally fistulated steers at 12-h intervals for 18-d periods in a latin square-designed experiment. Steers were fed semicontinuously (12 times daily) a 40:60 roughage:concentrate diet at twice their net energy requirement for maintenance. Ruminal digestion coefficients for DM, ADF and starch were 10 to 16% lower and linearly related in an inverse manner to the level of SF administered (P less than .05). Postruminal digestion of DM, ADF and starch increased as much as 46.7, 9.5 and 44.0%, respectively, in a fashion linearly related (P less than .05) to the level of SF administered. Total tract digestion of DM and ADF were not affected by SF; however, total tract starch digestion was increased as much as 5% and was related linearly (P less than .05) to SF treatment. With SF administration, as much as 13% more bacterial protein exited the rumen, resulting in a 16.5% linear improvement (P less than .1) in the efficiency of ruminal bacterial protein production per 100 g of OM fermented. Ruminal concentrations of VFA, ammonia and pH were not affected by SF. These results demonstrate a positive relationship between salivation and ruminal bacterial protein synthesis and suggest that feed utilization by ruminants may be improved by pharmacological stimulation of salivary secretions.

Effect of forage conservation method on ruminal lipid metabolism and microbial ecology in lactating cows fed diets containing a 60:40 forage-to-concentrate ratio.

PubMed

Halmemies-Beauchet-Filleau, A; Kairenius, P; Ahvenjärvi, S; Crosley, L K; Muetzel, S; Huhtanen, P; Vanhatalo, A; Toivonen, V; Wallace, R J; Shingfield, K J

2013-04-01

The effect of forage conservation method on ruminal lipid metabolism and microbial ecology was examined in 2 complementary experiments in cows. Treatments comprised fresh chopped grass, barn-dried hay, or untreated (UTS) or formic acid-treated silage (FAS) prepared from the same grass sward. Preparation of conserved forages coincided with the collection of samples from cows offered fresh grass. In the first experiment, 5 multiparous Finnish Ayrshire cows (229 d in milk) were used to compare the effects of feeding diets based on grass followed by hay during 2 consecutive 14-d periods separated by a 5-d transition during which extensively wilted grass was fed. In the second experiment, 5 multiparous Finnish Ayrshire cows (53 d in milk) were assigned to 1 of 2 blocks and allocated treatments according to a replicated 3×3 Latin square design with 14-d periods to compare the effects of hay, UTS, and FAS. Cows received 7 or 9 kg/d of the same concentrate in experiments 1 and 2, respectively. Conservation of grass by drying, but not ensiling, decreased forage fatty acid content primarily due to losses of 18:2n-6 and 18:3n-3. Compared with grass, feeding hay had no effect on dry matter intake (DMI), rumen pH, or fermentation characteristics, other than increasing ammonia content, but lowered whole-tract organic matter and fiber digestibility (experiment 1). Relative to hay, silage increased DMI, rumen volatile fatty acid (VFA) concentrations, and molar proportions of butyrate, and decreased molar acetate proportions (experiment 2). Compared with UTS, FAS increased DMI, had no effect on rumen ammonia or VFA concentrations, but tended to lower rumen pH and the molar ratio of lipogenic to glucogenic VFA. Conservation method had no substantial effect on ruminal or whole-tract digestibility coefficients. Compared with fresh grass and silages, hay decreased lipolysis and biohydrogenation (BH) of dietary unsaturates in the rumen, resulting in similar flows of 18:2n-6 and 18:3n-3, but lower amounts of trans-11 18:1 and Δ11,13 18:2 at the omasum. The extent of silage fermentation had minimal influence on ruminal lipid metabolism. Treatments were not associated with changes in the relative abundance of specific bacteria known to be capable of BH or rumen protozoal numbers. In conclusion, conservation method altered forage lipids, the extent of lipolysis and BH in the rumen, and the flow of fatty acids at the omasum, in the absence of substantial changes in ruminal Butyrivibrio populations. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The anatomy of object recognition--visual form agnosia caused by medial occipitotemporal stroke.

PubMed

Karnath, Hans-Otto; Rüter, Johannes; Mandler, André; Himmelbach, Marc

2009-05-06

The influential model on visual information processing by Milner and Goodale (1995) has suggested a dissociation between action- and perception-related processing in a dorsal versus ventral stream projection. It was inspired substantially by the observation of a double dissociation of disturbed visual action versus perception in patients with optic ataxia on the one hand and patients with visual form agnosia (VFA) on the other. Unfortunately, almost all cases with VFA reported so far suffered from inhalational intoxication, the majority with carbon monoxide (CO). Since CO induces a diffuse and widespread pattern of neuronal and white matter damage throughout the whole brain, precise conclusions from these patients with VFA on the selective role of ventral stream structures for shape and orientation perception were difficult. Here, we report patient J.S., who demonstrated VFA after a well circumscribed brain lesion due to stroke etiology. Like the famous patient D.F. with VFA after CO intoxication studied by Milner, Goodale, and coworkers (Goodale et al., 1991, 1994; Milner et al., 1991; Servos et al., 1995; Mon-Williams et al., 2001a,b; Wann et al., 2001; Westwood et al., 2002; McIntosh et al., 2004; Schenk and Milner, 2006), J.S. showed an obvious dissociation between disturbed visual perception of shape and orientation information on the one side and preserved visuomotor abilities based on the same information on the other. In both hemispheres, damage primarily affected the fusiform and the lingual gyri as well as the adjacent posterior cingulate gyrus. We conclude that these medial structures of the ventral occipitotemporal cortex are integral for the normal flow of shape and of contour information into the ventral stream system allowing to recognize objects.

Relationships between body fat accumulation, aerobic capacity and insulin resistance in Japanese participants.

PubMed

Yoshimura, Eiichi; Kumahara, Hideaki; Tobina, Takuro; Ayabe, Makoto; Matono, Sakiko; Anzai, Keizo; Higaki, Yasuki; Kiyonaga, Akira; Tanaka, Hiroaki

2011-01-01

This study evaluated the relationships between body fat accumulation, aerobic capacity and insulin resistance (HOMA-IR) in 61 Japanese participants. The participants were middle-aged to elderly (age: 33-73; BMI: 21.6-38.5). Body fat mass (FM) was evaluated by hydrostatic weighing. Computed tomography was used to evaluate visceral and subcutaneous fat areas (VFA and SFA), liver to spleen ratio (L/S), and low-density muscle area (LDMA). To assess aerobic capacity, VO2 at the lactate threshold (VO2@LT) and VO2 peak were measured using a bicycle ergometer. FM, VFA, SFA, LDMA and L/S significantly correlated with HOMA-IR, but VO2@LT and VO2 peak did not. Analysis of covariance after adjustment for VFA or other body fat distribution and aerobic capacity showed that HOMA-IR had a significant linear trend across the tertile groups of L/S. However, for FM, VFA, SFA, LDMA and VO2@LT or VO2 peak, no significant trend was observed between the tertiles and insulin resistance. Ectopic fat deposition in the liver may influence insulin resistance independently of other body fat accumulation and aerobic capacity in Japanese participants. © 2011 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.

Optimum design and operation of primary sludge fermentation schemes for volatile fatty acids production.

PubMed

Chanona, J; Ribes, J; Seco, A; Ferrer, J

2006-01-01

This paper presents a model-knowledge based algorithm for optimising the primary sludge fermentation process design and operation. This is a recently used method to obtain the volatile fatty acids (VFA), needed to improve biological nutrient removal processes, directly from the raw wastewater. The proposed algorithm consists in a heuristic reasoning algorithm based on the expert knowledge of the process. Only effluent VFA and the sludge blanket height (SBH) have to be set as design criteria, and the optimisation algorithm obtains the minimum return sludge and waste sludge flow rates which fulfil those design criteria. A pilot plant fed with municipal raw wastewater was operated in order to obtain experimental results supporting the developed algorithm groundwork. The experimental results indicate that when SBH was increased, higher solids retention time was obtained in the settler and VFA production increased. Higher recirculation flow-rates resulted in higher VFA production too. Finally, the developed algorithm has been tested by simulating different design conditions with very good results. It has been able to find the optimal operation conditions in all cases on which preset design conditions could be achieved. Furthermore, this is a general algorithm that can be applied to any fermentation-elutriation scheme with or without fermentation reactor.

Variation of bacterial communities and expression of Toll-like receptor genes in the rumen of steers differing in susceptibility to subacute ruminal acidosis.

PubMed

Chen, Yanhong; Oba, Masahito; Guan, Le Luo

2012-10-12

In order to determine differences in the ruminal bacterial community and host Toll-like receptor (TLR) gene expression of beef cattle with different susceptibility to acidosis, rumen papillae and content were collected from acidosis-susceptible (AS, n=3) and acidosis-resistant (AR, n=3) steers. The ruminal bacterial community was characterized using PCR-denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative real time PCR (qRT-PCR) analysis. Global R analysis of bacterial profile similarity revealed that bacterial diversity was significantly different between AR and AS groups for both rumen content (P=0.001) and epithelial (P=0.002) communities. The copy number of total bacterial 16S rRNA genes in content of AS steers was 10-fold higher than that of AR steers, and the copy number of total 16S rRNA genes of epimural bacteria in AR steers was positively correlated with ruminal pH (r=0.59, P=0.04), and negatively correlated with total VFA concentration (r=-0.59, P=0.05). The expressions of host TLR2 and 4 genes were significantly higher in AR steers compared to those in AS steers. These findings enhance our understanding about the ruminal microbial ecology and host gene expression changes that may be useful in the prevention of ruminal acidosis. Copyright © 2012 Elsevier B.V. All rights reserved.

Impact of diets with a high content of greaves-meal protein or carbohydrates on faecal characteristics, volatile fatty acids and faecal calprotectin concentrations in healthy dogs.

PubMed

Hang, Ingrid; Heilmann, Romy M; Grützner, Niels; Suchodolski, Jan S; Steiner, Jörg M; Atroshi, Faik; Sankari, Satu; Kettunen, Anu; de Vos, Willem M; Zentek, Jürgen; Spillmann, Thomas

2013-10-09

Research suggests that dietary composition influences gastrointestinal function and bacteria-derived metabolic products in the dog colon. We previously reported that dietary composition impacts upon the faecal microbiota of healthy dogs. This study aims at evaluating the dietary influences on bacteria-derived metabolic products associated with the changes in faecal microbiota that we had previously reported. We fed high-carbohydrate starch based (HCS), [crude protein: 194 g/kg, starch: 438 g/kg], high-protein greaves-meal (HPGM), [crude protein: 609 g/kg, starch: 54 g/kg] and dry commercial (DC), [crude protein: 264 g/kg, starch: 277 g/kg] diets, and studied their effects on the metabolism of the colonic microbiota and faecal calprotectin concentrations in five Beagle dogs, allocated according to the Graeco-Latin square design. Each dietary period lasted for three weeks and was crossed-over with washout periods. Food intake, body weight, and faecal consistency scores, dry matter, pH, ammonia, volatile fatty acids (VFAs), and faecal canine calprotectin concentrations were determined. Faecal ammonia concentrations decreased with the HCS diet. All dogs fed the HPGM diet developed diarrhoea, which led to differences in faecal consistency scores between the diets. Faecal pH was higher with the HPGM diet. Moreover, decreases in propionic and acetic acids coupled with increases in branched-chain fatty acids and valeric acid caused changes in faecal total VFAs in dogs on the HPGM diet. Faecal canine calprotectin concentration was higher with the HPGM diet and correlated positively with valeric acid concentration. The HPGM diet led to diarrhoea in all dogs, and there were differences in faecal VFA profiles and faecal canine calprotectin concentrations.

The physicochemical characteristics and anaerobic degradability of desiccated coconut industry waste water.

PubMed

Chanakya, H N; Khuntia, Himanshu Kumar; Mukherjee, Niranjan; Aniruddha, R; Mudakavi, J R; Thimmaraju, Preeti

2015-12-01

Desiccated coconut industries (DCI) create various intermediates from fresh coconut kernel for cosmetic, pharmaceutical and food industries. The mechanized and non-mechanized DCI process between 10,000 and 100,000 nuts/day to discharge 6-150 m(3) of malodorous waste water leading to a discharge of 264-6642 kg chemical oxygen demand (COD) daily. In these units, three main types of waste water streams are coconut kernel water, kernel wash water and virgin oil waste water. The effluent streams contain lipids (1-55 g/l), suspended solids (6-80 g/l) and volatile fatty acids (VFA) at concentrations that are inhibitory to anaerobic bacteria. Coconut water contributes to 20-50% of the total volume and 50-60% of the total organic loads and causes higher inhibition of anaerobic bacteria with an initial lag phase of 30 days. The lagooning method of treatment widely adopted failed to appreciably treat the waste water and often led to the accumulation of volatile fatty acids (propionic acid) along with long-chain unsaturated free fatty acids. Biogas generation during biological methane potential (BMP) assay required a 15-day adaptation time, and gas production occurred at low concentrations of coconut water while the other two streams did not appear to be inhibitory. The anaerobic bacteria can mineralize coconut lipids at concentrations of 175 mg/l; however; they are severely inhibited at a lipid level of ≥350 mg/g bacterial inoculum. The modified Gompertz model showed a good fit with the BMP data with a simple sigmoid pattern. However, it failed to fit experimental BMP data either possessing a longer lag phase and/or diauxic biogas production suggesting inhibition of anaerobic bacteria.

Effects of limestone on starch digestion in Holstein steers.

PubMed

Tissera, G H; Vandersall, J H; Erdman, R A

1988-03-01

Eight calcitic and three dolomitic limestones were examined for particle size and reactivity with hydrochloric acid at pH 3.5 and 5.5. Reactivity was higher in calcitic than dolomitic limestone. Within calcitic limestones, reactivity was highly related to particle size. A highly reactive limestone was selected for use in two digestion trials with Holstein steers. In Trial 1, 4 steers (approximately 300 kg) were fed diets consisting of 40% corn silage and 60% concentrate (DM basis) with .62 or 2.34% limestone in a single reversal trial with 3-wk experimental periods. Added limestone affected only starch digestibility, which increased from 91.3 to 93.2%. Fecal pH increased from 5.7 to 6.4 by limestone addition. In trial 2, four rumen and duodenally cannulated steers (approximately 475 kg) were fed the same diets in the same design. Limestone addition increased fecal pH from 5.7 to 6.5. There were no effects of limestone on rumen or total tract digestion of starch or other nutrients. Limestone addition had no effect on rumen pH, buffering capacity, or VFA concentrations. Addition of a highly reactive limestone to diets containing high amounts of starch had little effect on starch digestion in either the rumen or lower gastrointestinal tract.

Effect of ground corn cobs as a fiber source in total mixed ration on feed intake, milk yield and milk composition in tropical lactating crossbred Holstein cows.

PubMed

Wachirapakorn, Chalong; Pilachai, Krung; Wanapat, Metha; Pakdee, Pawadee; Cherdthong, Anusorn

2016-12-01

The aim of this study was to evaluate the effect of ground corn cobs (GCC) as a sole fiber source in total mixed ration (TMR) on feed intake, milk yield and milk composition in tropical lactating crossbred Holstein cows. Four multiparous crossbreds Holstein Friesian dairy cows with an initial body weight (BW) of 415.5 ± 26.20 kg were used in a 4 × 4 Latin square design. The dietary treatments of TMR contained a roughage-to-concentrate ratio of 40:60. The roughage source was used at different ratios of GCC to rice straw (RS) at 100:0, 82.5:17.5, 67.5:32.5, and 50:50 for TMR1 to TMR4, respectively. The results revealed significant improvements in intake of dry matter, protein, neutral detergent fiber (NDF) and metabolizable energy (ME) for TMR1 and TMR2 ( P  < 0.05), while the digestibility of nutrients was not altered by the treatments ( P  ≥ 0.05). Ground corn cobs was used for up to 100% of the total roughage without affecting milk production. Moreover, ruminal pH, temperature, ammonia-nitrogen (NH 3 -N) and volatile fatty acid (VFA) concentrations were not impacted by the treatments ( P  > 0.05). However, milk yield was significantly different among the GCC:RS ratios ( P  < 0.05) and was the highest in TMR1 and TMR2 (13.1 kg/d), while the milk compositions were not changed ( P  > 0.05). The results imply that using GCC as a whole roughage source significantly improved nutrients intake and milk yield in dairy cows raised in tropical areas.

Neil Armstrong Family Memorial Service

NASA Image and Video Library

2012-08-31

U.S. Navy F/A-18 jets from Strike Fighter Squadron (VFA) 106 and Strike Fighter Squadron (VFA) 34, from Naval Air Station Oceana (Va.) fly in a "Missing Man" formation over the Camargo Club following a memorial service celebrating the life of Neil Armstrong, Friday, Aug. 31, 2012, in Cincinnati. Armstrong, the first man to walk on the moon during the 1969 Apollo 11 mission, died Saturday, Aug. 25. He was 82. Photo Credit: (NASA/Bill Ingalls)

Effect of ensiled mulberry leaves and sun-dried mulberry fruit pomace on finishing steer growth performance, blood biochemical parameters, and carcass characteristics.

PubMed

Zhou, Zhenming; Zhou, Bo; Ren, Liping; Meng, Qingxiang

2014-01-01

Fifty-one Simmental crossbred steers (357.0 ± 16.5 kg) were used to compare a standard total mix ration (TMR) with variants on animal performance, ruminal fermentation, blood biochemical parameters, and carcass characteristics. Corn grain and cotton seed meal were partially replaced by ensiled mulberry leaves (EML) or sun-dried mulberry fruit pomace (SMFP). Experimental diets had similar amounts of crude protein (CP), acid detergent fiber (ADF), and metabolizable energy (ME). Animals were divided into three groups: control group (CONT), 8% EML group, and 6.3% SMFP group. Performance, including average daily weight gain (ADG), and dry matter intake (DMI), was measured. Blood and rumen samples were collected at the end of the experiment (16 weeks). There were no differences in final body weight (P = 0.743), ADG (P = 0.425), DMI (P = 0.642), or ADG/DMI (P = 0.236) between the groups. There were no differences (P = 0.2024) in rumen pH values; ammonia N was lower (P = 0.0076) in SMFP than in the EML and CONT groups. There were differences in the concentrations of total and individual volatile fatty acids, while no differences were determined in blood biochemical parameters (i.e., plasma glucose, urea concentrations, triglycerides, total protein, insulin, IgG, alanine transaminase, and aspartate aminotransferase, P ≥ 0.098). No differences were observed in carcass characteristics (P ≥ 0.513), tenderness (P = 0.844), adipose and lean color values (P ≥ 0.149), and chemical composition (P ≥ 0.400); however, intramuscular fat was lower in the EML and SMFP groups compared to the CONT animals (P = 0.034). In conclusion, diets supplemented with these two mulberry products in an isocaloric and isonitrogenous manner have similar effects to corn grain and cotton seed meals on steer performance, blood biochemical parameters and carcass characteristics, with the exception of ruminal VFA concentrations and lower intramuscular fat content.

Measurement of non-enteric emission fluxes of volatile fatty acids from a California dairy by solid phase micro-extraction with gas chromatography/mass spectrometry

NASA Astrophysics Data System (ADS)

Alanis, Phillip; Sorenson, Mark; Beene, Matt; Krauter, Charles; Shamp, Brian; Hasson, Alam S.

Dairies are a major source of volatile organic compounds (VOCs) in California's San Joaquin Valley; a region that experiences high ozone levels during summer. Short-chain carboxylic acids, or volatile fatty acids (VFAs), are believed to make up a large fraction of VOC emissions from these facilities, although there are few studies to substantiate this. In this work, a method using a flux chamber coupled to solid phase micro-extraction (SPME) fibers followed by analysis using gas chromatography/mass spectrometry was developed to quantify emissions of six VFAs (acetic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid and 3-methyl butanoic acid) from non-enteric sources. The technique was then used to quantify VFA fluxes from a small dairy located on the campus of California State University Fresno. Both animal feed and animal waste are found to be major sources of VFAs, with acetic acid contributing 70-90% of emissions from the sources tested. Measured total acid fluxes during spring (with an average temperature of 20 °C) were 1.84 ± 0.01, 1.06 ± 0.08, (1.3 ± 0.5) × 10 -2, (1.7 ± 0.2) × 10 -2 and (1.2 ± 0.5) × 10 -2 g m -2 h -1 from silage, total mixed rations, flushing lane, open lot and lagoon sources, respectively. VFA emissions from the sources tested total 390 ± 80 g h -1. The data indicate high fluxes of VFAs from dairy facilities, but differences in the design and operation of dairies in the San Joaquin Valley as well as seasonal variations mean that additional measurements must be made to accurately determine emissions inventories for the region.

Co-composting of Beef Cattle Feedlot Manure with Construction and Demolition Waste.

PubMed

Hao, Xiying; Hill, Brett; Caffyn, Pam; Travis, Greg; Olson, Andrew F; Larney, Francis J; McAllister, Tim; Alexander, Trevor

2014-09-01

With increased availability of dried distillers' grains with solubles (DDGS) as cattle feed and the need to recycle organic wastes, this research investigated the feasibility of co-composting DDGS cattle feedlot manure with construction and demolition (C&D) waste. Manure was collected from cattle fed a typical western Canadian finishing diet (CK) of 860 g rolled barley ( L.) grain, 100 g barley silage, and 40 g vitamin and mineral supplement kg dry matter (DM) and from cattle fed the same diet but (DG manure) with 300 g kg DM barley grain being replaced by DDGS. The CK and DG manures were co-composted with and without C&D waste in 13 m bins. Compost materials were turned on Days 14, 37, and 64, and terminated on Day 99. Adding C&D waste led to higher compost temperatures (0.4 to 16.3°C, average 7.2°C) than manure alone. Final composts had similar total C, total N, C/N ratios, and water-extractable K, Mg, and NO content across all treatments. However, adding C&D waste increased δC, δN, water-extractable SO, and Ca contents and decreased pH, total P (TP), water-extractable C, N, and P and most volatile fatty acids (VFA). The higher C&D compost temperatures should reduce pathogens while reduced VFA content should reduce odors. When using the final compost product, the increased SO and reduced TP and available N and P content in C&D waste compost should be taken into consideration. Increased S content in C&D compost may be beneficial for some crops grown on S-deficient soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Potential of extracts from Saponaria officinalis and Calendula officinalis to modulate in vitro rumen fermentation with respect to their content in saponins.

PubMed

Budan, Alexandre; Bellenot, Denis; Freuze, Ingrid; Gillmann, Louisa; Chicoteau, Pierre; Richomme, Pascal; Guilet, David

2014-01-01

Saponins have the potential to favorably modulate rumen fermentation, but there is generally a lack of the chemical structures associated with the described effects. The activity of extracts from Calendula officinalis and Saponaria officinalis in the rumen was evaluated in vitro. The S. officinalis root extract, reduced CH₄ production by 8.5% and increased total VFA concentration by 25.2%. C. officinalis and S. officinalis root extracts and the S. officinalis aerial part extract decreased the acetate to propionate ratio from 8.6 to 17.4%, according to the extract. An HPLC-ELSD analysis indicated that the saponin content ranged from 43.6 to 57.6 mg/g of dry matter (DM) in the C. officinalis extracts and from 224.0 to 693.8 mg/g of DM in the S. officinalis extracts, expressed as the hederacoside C equivalent. Identification of the saponin compounds present in the extracts by HPLC-MS(n) suggested that the saponin profile modulated the biological activities, showing the importance of determining the structure of saponins when evaluating extracts.

Bio-electrochemical remediation of real field petroleum sludge as an electron donor with simultaneous power generation facilitates biotransformation of PAH: effect of substrate concentration.

PubMed

Chandrasekhar, K; Venkata Mohan, S

2012-04-01

Remediation of real-field petroleum sludge was studied under self-induced electrogenic microenvironment with the function of variable organic loads (OLs) in bio-electrochemical treatment (BET) systems. Operation under various OLs documented marked influence on both electrogenic activity and remediation efficiency. Both total petroleum hydrocarbons (TPH) and its aromatic fraction documented higher removal with OL4 operation followed by OL3, OL2, OL1 and control. Self-induced biopotential and associated multiple bio-electrocatalytic reactions during BET operation facilitated biotransformation of higher ring aromatics (5-6) to lower ring aromatic (2-3) compounds. Asphaltenes and NSO fractions showed negligible removal during BET operation. Higher electrogenic activity was recorded at OL1 (343mV; 53.11mW/m(2), 100Ω) compared to other three OLs operation. Bioaugmentation to anodic microflora with anaerobic culture documented enhanced electrogenic activity at OL4 operation. Voltammetric profiles, Tafel analysis and VFA generation were in agreement with the observed power generation and degradation efficiency. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biological hydrolysis pretreatment on secondary sludge: Enhancement of anaerobic digestion and mechanism study.

PubMed

Ding, Huihuang H; Chang, Sheng; Liu, Yi

2017-11-01

The performance of biological hydrolysis (BH) pretreatment on municipal secondary sludge was evaluated in this study. During 6-day BH at 42°C (BH42), soluble chemical oxygen demand (sCOD) increased from 175.2±38.2mg/L to 3314.5±683.4mg/L; the dominant volatile fatty acid (VFA) was acetic acid, and its concentration increased from 41.5±2.1mg/L to 786.0±133.2mg/L. The extracted extracellular polymeric substances (EPS) from untreated secondary sludge contained three main fractions, and Fraction I gradually decreased from 133.9kDa to 24.9kDa during 6-day BH42. The BH pre-treatment at 42°C and 55°C both achieved more than 4-log reduction of total coliforms and 3-log reduction of E. coli. The BH pretreated secondary sludge at 15-day biochemical methane potential (BMP) test was comparable with the untreated secondary sludge after 30-day BMP, showing a significant enhancement on the acceleration of biogas production by BH pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aged refuse enhances anaerobic digestion of waste activated sludge.

PubMed

Zhao, Jianwei; Gui, Lin; Wang, Qilin; Liu, Yiwen; Wang, Dongbo; Ni, Bing-Jie; Li, Xiaoming; Xu, Rui; Zeng, Guangming; Yang, Qi

2017-10-15

In this work, a low-cost alternative approach (i.e., adding aged refuse (AR) into waste activated sludge) to significantly enhance anaerobic digestion of sludge was reported. Experimental results showed that with the addition dosage of AR increasing from 0 to 400 mg/g dry sludge soluble chemical oxygen demand (COD) increased from 1150 to 5240 mg/L at the digestion time of 5 d, while the maximal production of volatile fatty acids (VFA) increased from 82.6 to 183.9 mg COD/g volatile suspended solids. Although further increase of AR addition decreased the concentrations of both soluble COD and VFA, their contents in these systems with AR addition at any concentration investigated were still higher than those in the blank, which resulted in higher methane yields in these systems. Mechanism studies revealed that pertinent addition of AR promoted solubilization, hydrolysis, and acidogenesis processes and did not affect methanogenesis significantly. It was found that varieties of enzymes and anaerobes in AR were primary reason for the enhancement of anaerobic digestion. Humic substances in AR benefited hydrolysis and acidogenesis but inhibited methanogenesis. The effect of heavy metals in AR on sludge anaerobic digestion was dosage dependent. Sludge anaerobic digestion was enhanced by appropriate amounts of heavy metals but inhibited by excessive amounts of heavy metals. The relative abundances of microorganisms responsible for sludge hydrolysis and acidogenesis were also observed to be improved in the system with AR addition, which was consistent with the performance of anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative Demonstration of Active and Semi-Passive in Situ Bioremediation Approaches for Perchlorate-Impacted Groundwater at Longhorn Army Ammunitions Plant

DTIC Science & Technology

2009-01-01

wells in order to achieve the desired electron donor coverage. Soluble electron donors such as sodium lactate, citric acid , or ethanol have been used in...ORP) Monitoring.............39 6.7.5 Results of Volatile Fatty Acids (VFA) Analysis............................39 6.7.6 Results of Sulfate Analysis...VC vinyl chloride VFA volatile fatty acid VOC volatile organic compounds Technical material contained in this report has been approved for

Effects of Visceral Fat Accumulation Awareness on a Web-Based Weight-Loss Program: Japanese Study of Visceral Adiposity and Lifestyle Information-Utilization and Evaluation (J-VALUE).

PubMed

Sakane, Naoki; Dohi, Seitaro; Sakata, Koichi; Hagiwara, Shin-Ichi; Morimoto, Toshihisa; Uchida, Takanobu; Katashima, Mitsuhiro; Yanagisawa, Yoshiko; Yasumasu, Takeshi; Study Group, J-Value

2013-01-01

A reduction of visceral fat is important for improvement of metabolic risk. This study was designed to compare the effects of a web-based program alone or together with measurement and self-awareness of accumulated visceral fat in Japanese workers. A new noninvasive device to measure visceral fat accumulation was introduced, and efficacy on weight-loss and improvement of healthy behaviors were examined. This study was conducted according to Helsinki declaration and approved by the ethical committee of Japan Hospital Organization, National Kyoto Hospital. Two-hundred and sixteen overweight and obese males with BMI of more than 23 participated from 8 healthcare offices of 3 Japanese private companies. Subjects were randomly allocated into control group, Web-based weight-loss program (Web), or Web + Visceral fat measurement group (Web + VFA). Eighty-one percent of participants completed the study. Reductions of body weight, waist circumference, and BMI were the largest in Web + VFA group, and the differences between groups were significant by ANOVA. Improvements of healthy behaviors were the largest in Web + VFA group, and the differences of healthy eating improvement scores between Web + VFA and control groups were significant. Our findings suggest that measurement and awareness of visceral fat are effective in weight reduction in overweight and obese males in the workplace.

Modified ADM1 for modeling free ammonia inhibition in anaerobic acidogenic fermentation with high-solid sludge.

PubMed

Bai, Jie; Liu, He; Yin, Bo; Ma, Huijun; Chen, Xinchun

2017-02-01

Anaerobic acidogenic fermentation with high-solid sludge is a promising method for volatile fatty acid (VFA) production to realize resource recovery. In this study, to model inhibition by free ammonia in high-solid sludge fermentation, the anaerobic digestion model No. 1 (ADM1) was modified to simulate the VFA generation in batch, semi-continuous and full scale sludge. The ADM1 was operated on the platform AQUASIM 2.0. Three kinds of inhibition forms, e.g., simple inhibition, Monod and non-inhibition forms, were integrated into the ADM1 and tested with the real experimental data for batch and semi-continuous fermentation, respectively. The improved particle swarm optimization technique was used for kinetic parameter estimation using the software MATLAB 7.0. In the modified ADM1, the K s of acetate is 0.025, the k m,ac is 12.51, and the K I_NH3 is 0.02, respectively. The results showed that the simple inhibition model could simulate the VFA generation accurately while the Monod model was the better inhibition kinetics form in semi-continuous fermentation at pH10.0. Finally, the modified ADM1 could successfully describe the VFA generation and ammonia accumulation in a 30m 3 full-scale sludge fermentation reactor, indicating that the developed model can be applicable in high-solid sludge anaerobic fermentation. Copyright © 2016. Published by Elsevier B.V.

Effect of sprouted barley grain supplementation of an herbage-based or haylage-based diet on ruminal fermentation and methane output in continuous culture.

PubMed

Hafla, A N; Soder, K J; Brito, A F; Rubano, M D; Dell, C J

2014-12-01

A 4-unit dual-flow continuous-culture fermentor system was used to assess the effect of supplementing 7-d sprouted barley (SB) or barley grain (BG) with an herbage-based or haylage-based diet on nutrient digestibility, volatile fatty acid (VFA) profiles, bacterial protein synthesis, and methane (CH4) output. Treatments were randomly assigned to fermentors in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement using 7 d for diet adaptation and 3 d for sample collection. Experimental diets were (1) 55.5 g of herbage dry matter (DM) + 4.5 g of SB DM, (2) 56.0 g of herbage DM + 4.0 g of BG DM, (3) 55.5 g of haylage DM + 4.5 g of SB DM, and (4) 56.0 g of haylage DM + 4.0 g of BG DM. Forages were fed at 0730, 1030, 1400, and 1900 h, whereas SB and BG were fed at 0730 and 1400 h. Gas samples for CH₄ analysis were collected at 0725, 0900, 1000, 1355, 1530, and 1630 h on d 8, 9, and 10. Fluid samples were taken once daily on d 8, 9, and 10 for pH measurements and for ammonia-N and VFA analysis and analyzed for DM, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber for determination of nutrient digestibilities and estimation of bacterial protein synthesis. Orthogonal contrasts were used to compare the effect of forage source (haylage vs. herbage), supplement (BG vs. SB), and the forage × supplement interaction. Apparent and true DM and organic matter digestibilities as well as apparent crude protein digestibility were not affected by forage source. However, true DM digestibility was greatest for diets supplemented with SB. Apparent neutral and acid detergent fiber digestibilities of herbage-based diets were higher than haylage-based diets but fiber digestibility was not affected by supplement. Diets supplemented with SB had higher mean and minimum pH than BG; however, maximum pH was not affected by diet. Supplementation with BG produced a greater concentration of total VFA compared with diets supplemented with SB. Haylage-based diets produced greater CH4 output compared with herbage-based diets but supplementation did not affect CH4 output. Efficiency of bacterial protein synthesis was greater for herbage-based diets compared with haylage-based diets, with no effect of supplementation. Overall, supplementation with SB marginally increased true DM digestibility of herbage- and haylage-based diets but did not affect fiber and crude protein digestibilities, CH4 output, and bacterial efficiency, compared with BG. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Influence of genotype and diet on steer performance, manure odor, and carriage of pathogenic and other fecal bacteria. III. Odorous compound production.

PubMed

Miller, D N; Berry, E D; Wells, J E; Ferrell, C L; Archibeque, S L; Freetly, H C

2006-09-01

Three beef cattle diets were assessed for their potential to produce odorous compounds from cattle feces excreted during the growing and finishing periods. Eight pens containing 51 steers of varying proportions of Brahman and MARC III genotypes were fed either a chopped bromegrass hay diet or a corn silage diet for a 119-d growing period. After the growing period, all steers were switched to the same high-corn finishing diet (high corn) and fed to a target weight of 560 kg (finishing period). Fecal slurries were prepared from a composite of fresh fecal pats collected in each pen during both periods and incubated anaerobically. In additional flasks, starch, protein, or cellulose was added to the composite fecal subsamples to determine the preferred substrates for fermentation and odorous compound production. The content and composition of the fermentation products varied both initially and during the incubation, depending on the diet fed to the steers. The corn silage and high corn feces had the greater initial content of VFA (381.0 and 524.4 micromol/g of DM, respectively) compared with the bromegrass feces (139.3 micromol/g of DM) and accumulated more VFA than the bromegrass feces during the incubation. l-Lactic acid and VFA accumulation in the high corn and corn silage feces was at the expense of starch, based on starch loss and the production of straight-chain VFA. In the bromegrass feces, accumulation of branched-chain VFA and aromatic compounds and the low starch availability indicated that the protein in the feces was the primary source for odorous compound production. Substrate additions confirmed these conclusions. We conclude that starch availability was the primary factor determining accumulation and composition of malodorous fermentation products, and when starch was unavailable, fecal microorganisms utilized protein.

Dual Approach to Vibrational Spectra in Solution: Microscopic Influence of Hydrogen Bonding to the State of Motion of Glycine in Water.

PubMed

Kitamura, Yukichi; Takenaka, Norio; Koyano, Yoshiyuki; Nagaoka, Masataka

2014-08-12

We have proposed a new theoretical methodology to clarify the microscopic nature of the vibrational properties in solution, which consists of a combination of the vibrational frequency analyses (VFAs) with two kinds of Hessian matrices, that is, the effective Hessian on the free energy surface (free energy Hessian: "FE-Hessian") and the instantaneous one (instantaneous normal mode Hessian: "INM-Hessian") within QM/MM framework. In these VFAs, the Hessians were obtained by the analytical approach, having the advantages from the aspect of both the computational efficiency and accuracy in comparison to those obtained by the numerical one. In the present study, we have applied them to the glycine aqueous solution. First, by using the VFA with the FE-Hessian (VFA-FEH), we estimated the vibrational frequency shifts induced by solvent water molecules. The calculated values were quantitatively in agreement with experimental ones. It was clearly demonstrated that such vibrational shifts are attributed to not only the structural relaxation but also the explicit solute-solvent interactions (i.e., interatomic interactions). Second, by using the VFA with the INM-Hessian (VFA-INMH), the vibrational spectra in solution were investigated through the vibrational INM densities of states (DOS). By the comparison between the spectroscopic features and the microscopic solvation structure around glycine molecule, it was found that the frequency shifts and bandwidths in IR spectra are closely correlated with the hydrogen bonding (HB) network formations. In particular, the instantaneous changes of vibrational states of the hydroxyl group and carbonyl one, showing apparently inverse tendency on the strength of the HB interaction, can be explained very well on the basis of two different mechanisms, that is, the direct change of electron density in the bonding orbitals and the indirect one due to hyperconjugation between the lone electron pair and the antibonding orbitals, respectively. In conclusion, the present dual VFA approach is a quite useful strategy to interpret the microscopic origin of the experimental vibrational spectra.

In vitro effect of dietary protein level and nondigestible oligosaccharides on feline fecal microbiota.

PubMed

Pinna, C; Stefanelli, C; Biagi, G

2014-12-01

The aim of the present study was to evaluate in vitro the effect of some prebiotic substances and 2 dietary protein levels on the composition and activity of feline fecal microbiota. Two in vitro studies were conducted. First, 6 nondigestible oligosaccharides were studied; treatments were control diet (CTRL), gluconic acid (GA), carrot fiber (CF), fructooligosaccharides (FOS), galactooligosaccharides (GOS), lactitol (LAC), and pectins from citrus fruit (PEC). Substrates were added to feline fecal cultures at 2 g/L for 24 h incubation. Compared with the CTRL, ammonia had been reduced (P<0.05) by GOS (-9%) after 6 h and by GA (-14%), LAC (-12%), and PEC (-10%) after 24 h. After 24 h, all treatments had resulted in a lower pH versus the CTRL. Putrescine concentrations at 24 h were greater (P<0.05) in cultures treated with FOS (+90%), GOS (+96%), and LAC (+87%). Compared with the CTRL, total VFA were higher (P<0.05) in bottles containing CF (+41%), whereas the acetic to propionic acid ratio was reduced by LAC (-51%; P<0.05). After 24 h, Enterobacteriaceae had been reduced (P<0.05) by LAC and PEC. In a second study, LAC and FOS were selected to be tested in the presence of 2 diets differing in their protein content. There were 6 treatments: low-protein (LP) CTRL with no addition of prebiotics (CTRL-LP), high-protein (HP) CTRL with no addition of prebiotics (CTRL-HP), LP diet plus FOS, CTRL-HP plus FOS, LP diet plus LAC, and CTRL-HP plus LAC. Both FOS and LAC were added to feline fecal cultures at 2 g/L for 24 h incubation. Ammonia at 24 h was affected (P<0.05) by the protein level (36.2 vs. 50.2 mmol/L for LP and HP, respectively). The CTRL-HPs resulted in a higher pH and increased concentrations of biogenic amines were found after 6 and 24 h of incubation (P<0.05); putrescine at 24 h showed an increase (P<0.05) in cultures treated with FOS. Total VFA were influenced (P<0.05) by the protein level (40.9 vs. 32.6 mmol/L for LP and HP, respectively). At 24 h, the CTRL-HPs were associated with increased Clostridium perfringens and reduced Lactobacillus spp. and enterococci counts (P<0.05). The results from the present study show that different prebiotics exert different effects on the composition and activity of feline intestinal microbiota and that high dietary protein levels in a cat's diet can have negative effects on the animal intestinal environment.

Starch and fiber properties affect their kinetics of digestion and thereby digestive physiology in pigs.

PubMed

Zijlstra, R T; Jha, R; Woodward, A D; Fouhse, J; van Kempen, T A T G

2012-12-01

Traditionally in swine nutrition, analyses of starch and fiber have focused on assessing quantity; however, both have a wide range of functional properties making them underappreciated nutrients. Starch ranging from low to high amylose changes from rapidly digestible in the upper gut to poorly digestible but fermentable in the lower gut thereby changing from a source of glucose to VFA source. Likewise, fibers ranging from low to high viscosity affect digesta flow and from slowly to rapidly fermentable alter production of VFA serving as energy for the gut or whole body. Our hypothesis is that total extent, kinetics, and site of digestion or fermentation of starch and fiber are important for whole body nutrient use and intestinal health. To elucidate their effects, we developed in vitro, lab-based methodologies to describe kinetics of digestion and fermentation and linked these with in vivo models including i) ileum cannulation to collect digesta, ii) portal-vein catheterization to sequentially sample blood, iii) slaughter method to collect site-specific intestinal tissue and digesta, and iv) indirect calorimetry. Using these methods, kinetics of nutrient absorption was associated with pancreatic and intestinal hormones released into the portal vein, intestinal microbiota, and gene expression in intestinal tissue and microbiota. These studies confirmed that slowly digestible starch is partially degraded in the distal small and large intestine and fermented into VFA including butyrate (10-fold increase in net portal appearance), which reduces insulin responses by 60% and whole body energy use. Starch entering the distal intestine altered mRNA abundance of nutrient transporters and was bifidogenic. Extremely viscous purified fiber dampened glycemic responses and reduced digesta passage rate by 50% thereby increasing ileal digestion of dietary nutrients whereas increased fiber in feed grains reduced nutrient digestibility. Fermentable fiber increased butyrate and insulin production. These methods will therefore support elucidation of mechanisms that link starch and fiber properties to whole body nutrient use and intestinal health.

Effect of disodium/calcium malate or supplementation on growth performance, carcass quality, ruminal fermentation products, and blood metabolites of heifers.

PubMed

Carrasco, C; Medel, P; Fuentetaja, A; Ranilla, M J; Carro, M D

2016-10-01

The aim of this study was to assess the effects of malate salts and culture on growth performance, carcass quality, ruminal fermentation products, and blood metabolites in heifers raised under southern Europe practical farm conditions. A total of 108 Charolaise cross heifers (214 ± 27.3 kg BW and 6.4 ± 1.1 mo of age) were housed in 18 pens of 6 animals each and used in a 114-d feedlot study. There was a totally randomized experimental design, and 6 pens were assigned to each of the following experimental diets: a control (no supplementation), the control plus 4 g of disodium/calcium malate mixture per kilogram of concentrate (2.12 g malate/kg), and the control plus 0.15 g of CBS 493.94 per kilogram of concentrate (1.5 × 10 cfu/kg). The control diet consisted of wheat-barley-based pelleted concentrate (32% starch, DM basis) and full-length barley straw. Concentrate and straw were fed separately ad libitum (5% orts) in an 88:12 ratio. On Days 0, 56, and 114, ruminal fluid and blood samples were obtained from each heifer between 2 and 2.5 h after the morning feeding by ruminocentesis and tail venipuncture, respectively. Body weight, concentrate ADFI, and G:F were recorded at 28, 56, 84, and 114 d. At slaughter, hot carcass weight and yield and carcass classification were determined in 2 representative heifers per pen (12 animals per dietary treatment). Supplementation with malate salts or did not affect concentrate ADFI ( = 0.98), ADG ( = 0.74), or G:F ( = 0.50) at any time during the experiment. At slaughter, there were no differences in carcass weight ( = 0.86), classification ( = 0.18), or carcass yield ( = 0.84) among experimental groups. Also, there were no differences treatments on ruminal pH ( = 0.24), ruminal fermentation products ( = 0.69, = 0.88, and = 0.93 for total VFA, NH-N, and lactate, respectively), and blood metabolites ( = 0.96, = 0.82, and = 0.15 for glucose, urea N, and lactate, respectively). In conclusion, under the feeding and management conditions of this study, diet supplementation with malate salts or did not have any significant effects on growth performance, carcass quality, ruminal fermentation products, and blood metabolites.

Improving production of volatile fatty acids from food waste fermentation by hydrothermal pretreatment.

PubMed

Yin, Jun; Wang, Kun; Yang, Yuqiang; Shen, Dongsheng; Wang, Meizhen; Mo, Han

2014-11-01

Food waste (FW) was pretreated by a hydrothermal method and then fermented for volatile fatty acid (VFAs) production. The soluble substance in FW increased after hydrothermal pretreatment (⩽200 °C). Higher hydrothermal temperature would lead to mineralization of the organic compounds. The optimal temperature for organic dissolution was 180 °C, at which FW dissolved 42.5% more soluble chemical oxygen demand than the control. VFA production from pretreated FW fermentation was significantly enhanced compared with the control. The optimal hydrothermal temperature was 160 °C with a VFA yield of 0.908 g/g VSremoval. Butyrate and acetate were the prevalent VFAs followed by propionate and valerate. FW fermentation was inhibited after 200 °C pretreatment. The VFAs were extracted from the fermentation broth by liquid-liquid extraction. The VFA recovery was 50-70%. Thus, 0.294-0.411 g VFAs could be obtained per gram of hydrothermally pretreated FW (in dry weight) by this method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative biochemical analysis during the anaerobic digestion of lignocellulosic biomass from six morphological parts of Williams Cavendish banana (Triploid Musa AAA group) plants.

PubMed

Kamdem, Irénée; Hiligsmann, Serge; Vanderghem, Caroline; Bilik, Igor; Paquot, Michel; Thonart, Philippe

2013-12-01

We studied banana lignocellulosic biomass (BALICEBIOM) that is abandoned after fruit harvesting, and assessed its biochemical methane potential, because of its potential as an energy source. We monitored biogas production from six morphological parts (MPs) of the "Williams Cavendish" banana cultivar using a modified operating procedure (KOP) using KOH. Volatile fatty acid (VFA) production was measured using high performance liquid chromatography. The bulbs, leaf sheaths, petioles-midribs, leaf blades, rachis stems, and floral stalks gave total biogas production of 256, 205, 198, 126, 253, and 221 ml g⁻¹ dry matter, respectively, and total biomethane production of 150, 141, 127, 98, 162, and 144 ml g⁻¹, respectively. The biogas production rates and yields depended on the biochemical composition of the BALICEBIOM and the ability of anaerobic microbes to access fermentable substrates. There were no significant differences between the biogas analysis results produced using KOP and gas chromatography. Acetate was the major VFA in all the MP sample culture media. The bioconversion yields for each MP were below 50 %, showing that these substrates were not fully biodegraded after 188 days. The estimated electricity that could be produced from biogas combustion after fermenting all of the BALICEBIOM produced annually by the Cameroon Development Corporation-Del Monte plantations for 188 days is approximately 10.5 × 10⁶ kW h (which would be worth 0.80-1.58 million euros in the current market). This bioenergy could serve the requirements of about 42,000 people in the region, although CH₄ productivity could be improved.

Effects of psychrophilic storage on manures as substrate for anaerobic digestion.

PubMed

Bergland, Wenche; Dinamarca, Carlos; Bakke, Rune

2014-01-01

The idea that storage can enhance manure quality as substrate for anaerobic digestion (AD) to recover more methane is evaluated by studying storage time and temperature effects on manure composition. Volatile fatty acids (VFA) and total dissolved organics (CODs) were measured in full scale pig manure storage for a year and in multiple flasks at fixed temperatures, mainly relevant for colder climates. The CODs generation, influenced by the source of the pig manure, was highest initially (0.3 g COD L(-1)d(-1)) gradually dropping for 3 months towards a level of COD loss by methane production at 15°C. Methane emission was low (<0.01 g COD L(-1)d(-1)) after a brief initial peak. Significant CODs generation was obtained during the warmer season (T > 10°C) in the full scale storage and almost no generation at lower temperatures (4-6°C). CODs consisted mainly of VFA, especially acetate. All VFAs were present at almost constant ratios. The naturally separated manure middle layer without sediment and coarser particles is suitable for sludge bed AD and improved further during an optimal storage time of 1-3 month(s). This implies that high rate AD can be integrated with regular manure slurry handling systems to obtain efficient biogas generation.

Effects of Psychrophilic Storage on Manures as Substrate for Anaerobic Digestion

PubMed Central

Bergland, Wenche; Dinamarca, Carlos

2014-01-01

The idea that storage can enhance manure quality as substrate for anaerobic digestion (AD) to recover more methane is evaluated by studying storage time and temperature effects on manure composition. Volatile fatty acids (VFA) and total dissolved organics (CODs) were measured in full scale pig manure storage for a year and in multiple flasks at fixed temperatures, mainly relevant for colder climates. The CODs generation, influenced by the source of the pig manure, was highest initially (0.3 g COD L−1d−1) gradually dropping for 3 months towards a level of COD loss by methane production at 15°C. Methane emission was low (<0.01 g COD L−1d−1) after a brief initial peak. Significant CODs generation was obtained during the warmer season (T > 10°C) in the full scale storage and almost no generation at lower temperatures (4–6°C). CODs consisted mainly of VFA, especially acetate. All VFAs were present at almost constant ratios. The naturally separated manure middle layer without sediment and coarser particles is suitable for sludge bed AD and improved further during an optimal storage time of 1–3 month(s). This implies that high rate AD can be integrated with regular manure slurry handling systems to obtain efficient biogas generation. PMID:25165712

Start-up of a pilot-scale anaerobic fixed film reactor at low temperature treating slaughterhouse wastewater.

PubMed

del Pozo, R; Diez, V; Salazar, G

2002-01-01

A pilot-scale anaerobic fixed film reactor (AFFR) with vertically arranged PVC tubes as biomass carrier, treating poultry slaughterhouse wastewater was started-up in 74 days at temperatures between 20-24 degrees C. The start-up process consisted of a long acclimatization phase followed by a low loaded growth phase, a gradual increase of OLR upto 9.2 kg COD/m3d, and a final maturation phase at moderated loads of 2.7 kg COD/m3d at which total COD removal efficiencies of 57% were achieved. Alkalinity ratio IA:PA was found to be the best control parameter to avoid VFA accumulation. OLR increase based on pH control was not satisfactory because changes in CO2 solubility caused daily by temperature and flow variations led to pH oscillations of 0.2 units. The low wastewater alkalinity, 260 mg/l CaCO3 was insufficient to buffer the pH system, therefore the pH decrease associated with the VFA accumulation was not easily detected and could not be used as a way of OLR control. Organic matter removal took place by accumulation and biodegradation processes. Limitation in the reactor hydrodynamics and particulate fraction hydrolysis was detected at high flow rates.

An assessment of the feasibility of employing biochemical acidogenic potential tests for characterizing anaerobic biodegradability of raw and pretreated waste activated sludge.

PubMed

Kianmehr, Peiman; Parker, Wayne; Seto, Peter

2012-04-01

The potential to use the results of biochemical acid potential (BAP) tests to predict the ultimate digestibility of raw and pretreated waste activated sludge (WAS) was investigated. The ultimate methane production from biochemical methane potential (BMP) tests on raw and pretreated samples which spanned a range of biodegradability proved linearly related to the volatile fatty acid (VFA) and soluble chemical oxygen demand (COD) production in corresponding BAP tests. In addition, a linear relationship between NH4-N production in the BMP and BAP tests was observed. Despite the linear nature of the relationships, the ratio of the production of methane in the BMP tests to the production of VFAs in the BAP tests varied with the biodegradability of the sludge samples. Waste Activated Sludge samples with low digestibility had ultimate yields of CH4 that were greater than the VFA yields in BAP tests, whereas sludge samples with high digestibility had lower yields of CH4 than the corresponding VFA yields. This trend contrasted with the NH4 results, in which the yields in the BAP tests were consistently less than those observed in the BMP tests. It was hypothesized that the varying relationship between CH4 and VFA yields was because of the inhibition of anaerobic oxidation of long-chain fatty acids (LCFAs) in the BAP tests. Long-chain fatty acids would be converted to CH4 in BMP tests but produced as digestion intermediates in the BAP tests and were not measured as part of the VFA yield. Hydrogen and acetate were identified as the two most likely intermediates that would accumulate in the BAP tests (which would cause inhibition). A stoichiometric model to facilitate the development of an improved understanding of the biodegradation processes in the BAP and BMP tests was assembled. When the model was applied to the BAP tests the anaerobic oxidation of LCFAs and propionate and methanogenesis were excluded from the model. The model was employed to estimate the extent of degradation of lipids, carbohydrates, and proteins in the batch tests as a function of the ultimate biodegradability of the sludge samples. On the basis of model fitting, it was determined that the degradation of lipids in BMP tests decreased, whereas the degradation of carbohydrates and proteins increased as the digestibility of the sludge samples increased. The varying ratio of lipid to protein and carbohydrate degradability with increasing digestibility of the sludge samples describes the relationship between VFA production and CH4 production in the BAP, and BMP tests, respectively.

Control of Microbial Sulfide Production with Biocides and Nitrate in Oil Reservoir Simulating Bioreactors

PubMed Central

Xue, Yuan; Voordouw, Gerrit

2015-01-01

Oil reservoir souring by the microbial reduction of sulfate to sulfide is unwanted, because it enhances corrosion of metal infrastructure used for oil production and processing. Reservoir souring can be prevented or remediated by the injection of nitrate or biocides, although injection of biocides into reservoirs is not commonly done. Whether combined application of these agents may give synergistic reservoir souring control is unknown. In order to address this we have used up-flow sand-packed bioreactors injected with 2 mM sulfate and volatile fatty acids (VFA, 3 mM each of acetate, propionate and butyrate) at a flow rate of 3 or 6 pore volumes (PV) per day. Pulsed injection of the biocides glutaraldehyde (Glut), benzalkonium chloride (BAC) and cocodiamine was used to control souring. Souring control was determined as the recovery time (RT) needed to re-establish an aqueous sulfide concentration of 0.8–1 mM (of the 1.7–2 mM before the pulse). Pulses were either for a long time (120 h) at low concentration (long-low) or for a short time (1 h) at high concentration (short-high). The short-high strategy gave better souring control with Glut, whereas the long-low strategy was better with cocodiamine. Continuous injection of 2 mM nitrate alone was not effective, because 3 mM VFA can fully reduce both 2 mM nitrate to nitrite and N2 and, subsequently, 2 mM sulfate to sulfide. No synergy was observed for short-high pulsed biocides and continuously injected nitrate. However, use of continuous nitrate and long-low pulsed biocide gave synergistic souring control with BAC and Glut, as indicated by increased RTs in the presence, as compared to the absence of nitrate. Increased production of nitrite, which increases the effectiveness of souring control by biocides, is the most likely cause for this synergy. PMID:26696994

Influence of Sunflower Whole Seeds or Oil on Ruminal Fermentation, Milk Production, Composition, and Fatty Acid Profile in Lactating Goats.

PubMed

Morsy, T A; Kholif, S M; Kholif, A E; Matloup, O H; Salem, A Z M; Elella, A Abu

2015-08-01

This study aimed to investigate the effect of sunflower seeds, either as whole or as oil, on rumen fermentation, milk production, milk composition and fatty acids profile in dairy goats. Fifteen lactating Damascus goats were divided randomly into three groups (n = 5) fed a basal diet of concentrate feed mixture and fresh Trifolium alexandrinum at 50:50 on dry matter basis (Control) in addition to 50 g/head/d sunflower seeds whole (SS) or 20 mL/head/d sunflower seeds oil (SO) in a complete randomized design. Milk was sampled every two weeks during 90 days of experimental period for chemical analysis and rumen was sampled at 30, 60, and 90 days of the experiment for ruminal pH, volatile fatty acids (tVFA), and ammonia-N determination. Addition of SO decreased (p = 0.017) ruminal pH, whereas SO and SS increased tVFA (p<0.001) and acetate (p = 0.034) concentrations. Serum glucose increased (p = 0.013) in SO and SS goats vs Control. The SO and SS treated goats had improved milk yield (p = 0.007) and milk fat content (p = 0.002). Moreover, SO increased milk lactose content (p = 0.048) and feed efficiency (p = 0.046) compared to Control. Both of SS and SO increased (p<0.05) milk unsaturated fatty acids content specially conjugated linolenic acid (CLA) vs Control. Addition of SS and SO increased (p = 0. 021) C18:3N3 fatty acid compared to Control diet. Data suggested that addition of either SS or SO to lactating goats ration had beneficial effects on milk yield and milk composition with enhancing milk content of healthy fatty acids (CLA and omega 3), without detrimental effects on animal performance.

Can fungal zoospores be the source of energy for the rumen protozoa Eudiplodinium maggii?

PubMed

Miltko, Renata; Bełżecki, Grzegorz; Kowalik, Barbara; Michałowski, Tadeusz

2014-10-01

Results of our earlier studies showed the ability of ciliates Eudiplodinium maggii to digest and metabolize commercial chitin. The natural source of this polysaccharide in the rumen are fungi. The objectives of present research were to determine the effect of fungal zoospores on the survival and population density of E. maggii to quantify the concentration of chitin in the cells of protozoa and to examine the ability of E. maggii, to ferment chitin of fungal zoospores. The cultivation experiment showed that the survival of protozoa was shorter than 4 days when the culture medium was composed of buffer solution and lyophilized fungal spores. An enrichment of this medium with wheat gluten prolonged the survival of ciliates up to 8 days. The supplementation of the last medium with meadow hay enabled the protozoa to survive for 28 days but a positive effect was observed only during the last 8 days of experiment. The chitin content was 0.27 ng and 0.21-0.35 ng per single zoospore and ciliate, respectively. An increase in the concentration of volatile fatty acids (VFA) was found when protozoa were incubated with zoospores. The production rate of VFA was 46.3 pM/protozoan per h whereas the endogenous production did not exceed 31 pM/protozoan per h. The molar proportion of acetic acid was 77.7% and these of butyric and propionic acids-12.2 and 11.0%, respectively. The obtained results make it evident that carbohydrates present in fungal zoospores were utilized by protozoa in energy yielding processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of inclusion levels of banana (Musa spp.) peelings on feed degradability and rumen environment of cattle fed basal elephant grass.

PubMed

Nambi-Kasozi, Justine; Sabiiti, Elly Nyambobo; Bareeba, Felix Budara; Sporndly, Eva; Kabi, Fred

2016-04-01

The effect of feeding varying banana peeling (BP) levels on rumen environment and feed degradation characteristics was evaluated using three rumen fistulated steers in four treatments. The steers were fed BP at 0, 20, 40, and 60% levels of the daily ration with basal elephant grass (EG) to constitute four diets. Maize bran, cotton seed cake, and Gliricidia sepium were offered to make the diets iso-nitrogenous. The nylon bag technique was used to measure BP and EG dry matter (DM), crude protein (CP), and neutral detergent fiber (NDF) degradabilities at 0, 6, 12, 24, 48, 72, 96, and 120 h. Rumen fluid samples were collected to determine pH and volatile fatty acid (VFA) concentrations. Effective DM, CP, and NDF degradabilities of BP ranged between 574 and 807, 629-802, and 527-689 g/kg, respectively, being lower at higher BP levels. Elephant grass degradability behaved similarly with relatively high effective CP degradability (548-569 g/kg) but low effective DM and NDF degradability (381-403 and 336-373 g/kg, respectively). Rumen pH and VFA reduced with increasing BP in the diets. Rumen pH dropped to 5.8 and 5.9 at the 40 and 60% BP feeding levels, respectively. Banana peelings were better degraded than EG but higher BP levels negatively affected feed degradability and rumen environment.

Alkaline fermentation of waste activated sludge stimulated by saponin: volatile fatty acid production, mechanisms and pilot-scale application.

PubMed

Huang, Xiangfeng; Mu, Tianshuai; Shen, Changming; Lu, Lijun; Liu, Jia

2016-12-01

Volatile fatty acid (VFA) production stimulated by saponin (SP), an environmentally friendly bio-surfactant, was investigated during sludge alkaline fermentation in laboratory studies and pilot applications. The combined use of SP and pH 9 condition significantly enhanced VFA production to approximately 425 mg COD/g VSS, which was 4.7-fold of raw sludge and 1.5-fold of sole pH 10 adjustment (the optimum pH for alkaline fermentation). Further results indicated that SP & pH 9 condition provided sufficient substrates for acidification and decreased the consumption of VFAs through methanogenesis. Moreover, SP accompanied by moderate alkaline condition (i.e. pH 9) showed weaker inhibitory effects on key enzyme activities and metabolic potential of acidification microorganisms than sole pH 10 adjustment. On this basis, a pilot-scale system involving anaerobic fermentation and anaerobic-anoxic-aerobic step-feed bioreaction tanks was established to study the potential of VFAs as supplementary carbon sources for wastewater treatment. The influent of the pilot system was sanitary wastewater characterized by low C/N ratios from a scenic rural area. After flocculation and nutrient precipitation, the fermentation supernatant was mixed with the influent at a volume ratio of 1:30. With this approach, nitrogen and phosphorus concentrations in effluent fulfilled the first-A wastewater discharge standard in China.

The Effect of increasing levels of date palm (Phoenix dactylifera L.) seed on the performance, ruminal fermentation, antioxidant status and milk fatty acid profile of Saanen dairy goats.

PubMed

Sharifi, M; Bashtani, M; Naserian, A A; Farhangfar, H

2017-10-01

This study was conducted to examine the effect of date palm (Phoenix dactylifera L.) seed (DPS) on the performance, ruminal fermentation, antioxidant status and milk fatty acid (FA) profile of dairy goats. Eight multiparous Saanen dairy goats, averaging 97 ± 7 days in milk (DIM) and 2150 ± 130 g of milk production, were used in a 4 × 4 replicated Latin square design. Experimental diets contained 0% (control), 6% (DPS6), 12% (DPS12) and 18% (DPS18) of DPS. Dry matter intake (DMI), milk production, and the composition and digestibility of the dry matter (DM), organic matter (OM), neutral detergent fibre (NDF) and crude protein (CP) were not affected by the diets. Adding DPS to the diet increased linearly total antioxidant capacity (TAC) in milk and blood (p < 0.05). No significant difference was found in the malondialdehyde (MDA) content in milk and blood. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in the blood, ruminal pH, NH 3 -N, ruminal total volatile fatty acid (VFA), acetate, butyrate, isovalerate and valeric acid concentration had no significant effect among the diets. The propionate acid concentration decreased linearly as DPS was added to the diet, and DPS18 had minimum propionate acid concentration (p < 0.05). The inclusion of DPS18 to diets increased linearly the proportion of C18:0 (compared to control) as well as cis-18:1, trans-18:1 (compared to control and DPS6) and decreased C14:1 (compared to control) in milk fat (p < 0.05). The concentration of conjugated linoleic acid (CLA) in DPS18 was higher than other diets (p = 0.04). The results of this study implied that replacing DPS with a part of dairy goats' ration had no negative effects on the performance of the animals and could also improve the antioxidant activity and increase the concentration of CLA in their milk. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates food waste.

PubMed

Sunyoto, Nimas M S; Zhu, Mingming; Zhang, Zhezi; Zhang, Dongke

2016-11-01

Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates was studied using bench-scale bioreactors. The cultures with biochar additions were placed in 100ml reactors and incubated at 35°C and pH 5 for hydrogen production. The residual cultures were then used for methane production, incubated at 35°C and pH 7. Daily yields of hydrogen and methane and weekly yield of volatile fatty acids (VFA) were measured. The hydrogen and methane production potentials, rate and lag phases of the two phases were analysed using the Gompertz model. The results showed that biochar addition increased the maximum production rates of hydrogen by 32.5% and methane 41.6%, improved hydrogen yield by 31.0% and methane 10.0%, and shortened the lag phases in the two phases by 36.0% and 41.0%, respectively. Biochar addition also enhanced VFA generation during hydrogen production and VFA degradation in methane production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of saponification on the anaerobic digestion of solid fatty residues.

PubMed

Mouneimne, A H; Carrère, H; Bernet, N; Delgenès, J P

2003-10-01

In France, fatty residues considered as "non-ultimate" waste will not be accepted in landfill from 2002, in accordance with French legislation. Anaerobic digestion appears as an alternative process to mobilize and profitably use such fermentable waste. In this work, the effect of an alkaline pretreatment on the degradation of hexane extractible matter (HEM) and the production of volatile fatty acids (VFAs) was compared in reactors working at pH 6.5 and 8.5. The results obtained showed that 40% (+/- 0.1) of HEM were degraded at pH 8.5 versus 10% (+/- 0.3) at pH 6.5, regardless of the alkali agent used to saponify the greasy wastes. The highest performances of VFA production (8.45% +/- 0.3) were obtained at pH 8.5 with greases saponified by potassium hydroxide, compared to results (4.25% +/- 0.1) with greasy waste saponified by sodium hydroxide. This difference in VFA production might be attributable to biotoxic molecules generated during the saponification of greases by soda, limiting consequently the VFA production process.

Semi-aerobic fermentation as a novel pre-treatment to obtain VFA and increase methane yield from primary sludge.

PubMed

Peces, M; Astals, S; Clarke, W P; Jensen, P D

2016-01-01

There is a growing trend to consider organic wastes as potential sources of renewable energy and value-add products. Fermentation products have emerged as attractive value-add option due to relative easy production and broad application range. However, pre-fermentation and extraction of soluble products may impact down-stream treatment processes, particularly energy recovery by anaerobic digestion. This paper investigates primary sludge pre-fermentation at different temperatures (20, 37, 55, and 70°C), treatment times (12, 24, 48, and 72h), and oxygen availability (semi-aerobic, anaerobic); and its impact on anaerobic digestion. Pre-fermentation at 20 and 37°C succeeded for VFA production with acetate and propionate being major products. Pre-fermentation at 37, 55, and 70°C resulted in higher solubilisation yield but it reduced sludge methane potential by 20%. Under semi-aerobic conditions, pre-fermentation allowed both VFA recovery (43gCODVFAkg(-1)VS) and improved methane potential. The latter phenomenon was linked to fungi that colonised the sludge top layer during pre-fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of pH on solubilization of organic matter and microbial community structures in sludge fermentation.

PubMed

Maspolim, Yogananda; Zhou, Yan; Guo, Chenghong; Xiao, Keke; Ng, Wun Jern

2015-08-01

Sludge fermentation between pH 4 and 11 was investigated to generate volatile fatty acids (VFA). Despite the highest sludge solubilization of 25.9% at pH 11, VFA accumulation was optimized at pH 8 (12.5% out of 13.1% sludge solubilization). 454 pyrosequencing identified wide diversity of acidogens in bioreactors operated at the various pHs, with Tissierella, Petrimonas, Proteiniphilum, Levilinea, Proteiniborus and Sedimentibacter enriched and contributing to the enhanced fermentation at pH 8. Hydrolytic enzymatic assays determined abiotic effect to be the leading cause for improved solubilization under high alkaline condition but the environmental stress at pH 9 and above might lead to disrupt biological activities and eventually VFA production. Furthermore, molecular weight (MW) characterization of the soluble fractions found large MW aromatic substances at pH 9 and above, that is normally associated with poor biodegradability, making them disadvantageous for subsequent bioprocesses. The findings provided information to better understand and control sludge fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Acidogenic fermentation of food waste for volatile fatty acid production with co-generation of biohydrogen.

PubMed

Dahiya, Shikha; Sarkar, Omprakash; Swamy, Y V; Venkata Mohan, S

2015-04-01

Fermentation experiments were designed to elucidate the functional role of the redox microenvironment on volatile fatty acid (VFA, short chain carboxylic acid) production and co-generation of biohydrogen (H2). Higher VFA productivity was observed at pH 10 operation (6.3g/l) followed by pH 9, pH 6, pH 5, pH 7, pH 8 and pH 11 (3.5 g/l). High degree of acidification, good system buffering capacity along with co-generation of higher H2 production from food waste was also noticed at alkaline condition. Experiments illustrated the role of initial pH on carboxylic acids synthesis. Alkaline redox conditions assist solubilization of carbohydrates, protein and fats and also suppress the growth of methanogens. Among the carboxylic acids, acetate fraction was higher at alkaline condition than corresponding neutral or acidic operations. Integrated process of VFA production from waste with co-generation of H2 can be considered as a green and sustainable platform for value-addition. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Effects of Thyme and Cinnamon Essential Oils on Performance, Rumen Fermentation and Blood Metabolites in Holstein Calves Consuming High Concentrate Diet

PubMed Central

Vakili, A. R.; Khorrami, B.; Mesgaran, M. Danesh; Parand, E.

2013-01-01

Essential oils have been shown to favorably effect in vitro ruminal fermentation, but there are few in vivo studies that have examined animal responses. The objective of this study was to evaluate the effects of thyme (THY) and cinnamon (CIN) essential oils on feed intake, growth performance, ruminal fermentation and blood metabolites in feedlot calves fed high-concentrate diets. Twelve growing Holstein calves (213±17 kg initial BW) were used in a completely randomized design and received their respective dietary treatments for 45 d. Treatments were: 1-control (no additive), 2-THY (5 g/d/calf) and 3-CIN (5 g/d/calf). Calves were fed ad libitum diets consisting of 15% forage and 85% concentrate, and adapted to the finishing diet by gradually increasing the concentrate ratio with feeding a series of transition diets 5 wk before the experiment started. Supplementation of THY or CIN did not affect DMI and ADG, and feed efficiency was similar between treatment groups. There were no effects of additives on ruminal pH and rumen concentrations of ammonia nitrogen and total VFA; whereas molar proportion of acetate and ratio of acetate to propionate decreased, and the molar proportion of propionate increased with THY and CIN supplementation. Rumen molar concentration of butyrate was significantly increased by adding CIN compared to control; but no change was observed with THY compared with control group. No effects of THY, or CIN were observed on valerate, isobutyrate or isovalerate proportions. Plasma concentrations of glucose, cholesterol, triglyceride, urea-N, β-hydroxybutyrate, alanine aminotransferase and aspartate aminotransferase were not changed by feeding THY or CIN. Results from this study suggest that supplementing a feedlot finishing diet with THY or CIN essential oil might be useful as ruminal fermentation modifiers in beef production systems, but has minor impacts on blood metabolites. PMID:25049871

Effects of different dietary ratio of metabolizable glucose and metabolizable protein on growth performance, rumen fermentation, blood biochemical indices and ruminal microbiota of 8 to 10-month-old heifers.

PubMed

Sun, Jie; Xu, Jinhao; Ge, Rufang; Wang, Hongrong; Wang, Mengzhi; Yu, Lihuai

2018-01-26

The aim of this experiment was to evaluate the effects of different dietary ratios of metabolizable glucose (MG) to metabolizable protein (MP) on growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of 8 to 10-month-old heifers. A total of 24 Holstein heifers weighing an average of 282.90 kg (8 month of age) were randomly assigned to four groups of six. The heifers were fed one of four diets of different dietary MG/MP (0.97, 1.07, 1.13 and 1.26). The results showed that the ratio of MG/MP affected the growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of heifers. The average daily gain (ADG) of heifers was enhanced by increasing the ratio of MG/MP (P < 0.05). The concentration of blood urea nitrogen (BUN), cholesterol (CHOL) and low density lipoprotein cholesterol (LDL-C) as well as the concentration of total volatile fatty acid (VFA) in the rumen fluid of heifers decreased with the improvement in the ratio of dietary MG/MP (P < 0.05). However, the relative amount of Ruminococcus albus and Butyrivibrio fibrisolvens in the rumen of heifers was increased significantly (P < 0.05) when the dietary MG/MP increased. At the same time, with the improvement in dietary MG/MP, the amount of Fibrobacter succinogenes increased (P = 0.08). A diet with an optimal ratio (1.13) of MG/MP was beneficial for the improvement of growth, rumen fermentation, dietary protein and energy utilization of 8 to 10-month-old heifers in this experiment.

Effect of high-dose nano-selenium and selenium-yeast on feed digestibility, rumen fermentation, and purine derivatives in sheep.

PubMed

Xun, Wenjuan; Shi, Liguang; Yue, Wenbin; Zhang, Chunxiang; Ren, Youshe; Liu, Qiang

2012-12-01

The aim of this study was to evaluate the effect of nano-selenium (NS) and yeast-selenium (YS) supplementation on feed digestibility, rumen fermentation, and urinary purine derivatives in sheep. Six male ruminally cannulated sheep, average 43.32 ± 4.8 kg of BW, were used in a replicated 3 × 3 Latin square experiment. The treatments were control (without NS and YS), NS with 4 g nano-Se (provide 4 mg Se), and YS with 4 g Se-yeast (provide 4 mg Se) per kilogram of diet dry matter (DM), respectively. Experimental periods were 25 days with 15 days of adaptation and 10 days of sampling. Ruminal pH, ammonia N concentration, molar proportion of propionate, and ratio of acetate to propionate were decreased (P < 0.01), and total ruminal VFA concentration was increased with NS and YS supplementation (P < 0.01). In situ ruminal neutral detergent fiber (aNDF) degradation of Leymus chinensis (P < 0.01) and crude protein (CP) of soybean meal (P < 0.01) were significantly improved by Se supplementation. Digestibilities of DM, organic matter, crude protein, ether extract, aNDF, and ADF in the total tract and urinary excretion of purine derivatives were also affected by feeding Se supplementation diets (P < 0.01). Ruminal fermentation was improved by feeding NS, and feed conversion efficiency was also increased compared with YS (P < 0.01). We concluded that nano-Se can be used as a preferentially available selenium source in ruminant nutrition.

Dose-response effects of dietary pequi oil on fermentation characteristics and microbial population using a rumen simulation technique (Rusitec).

PubMed

Duarte, Andrea Camacho; Durmic, Zoey; Vercoe, Philip E; Chaves, Alexandre V

2017-12-01

The effect of increasing the concentration of commercial pequi (Caryocar brasiliense) oil on fermentation characteristics and abundance of methanogens and fibrolityc bacteria was evaluated using the rumen simulation technique (Rusitec). In vitro incubation was performed over 15 days using a basal diet consisting of ryegrass, maize silage and concentrate in equal proportions. Treatments consisted of control diet (no pequi oil inclusion, 0 g/kg DM), pequi dose 1 (45 g/kg DM), and pequi dose 2 (91 g/kg DM). After a 7 day adaptation period, samples for fermentation parameters (total gas, methane, and VFA production) were taken on a daily basis. Quantitative real time PCR (q-PCR) was used to evaluate the abundance of the main rumen cellulolytic bacteria, as well as abundance of methanogens. Supplementation with pequi oil did not reduce overall methane production (P = 0.97), however a tendency (P = 0.06) to decrease proportion of methane in overall microbial gas was observed. Increasing addition of pequi oil was associated with a linear decrease (P < 0.01) in dry matter disappearance of maize silage. The abundance of total methanogens was unchanged by the addition of pequi oil, but numbers of those belonging to Methanomassiliicoccaceae decreased in liquid-associated microbes (LAM) samples (P < 0.01) and solid-associated microbes (SAM) samples (P = 0.09) respectively, while Methanobrevibacter spp. increased (P < 0.01) only in SAM samples. Fibrobacter succinogenes decreased (P < 0.01) in both LAM and SAM samples when substrates were supplemented with pequi oil. In conclusion, pequi oil was ineffective in mitigating methane emissions and had some adverse effects on digestibility and selected fibrolytic bacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aged-engineered nanoparticles effect on sludge anaerobic digestion performance and associated microbial communities.

PubMed

Eduok, Samuel; Ferguson, Robert; Jefferson, Bruce; Villa, Raffaella; Coulon, Frédéric

2017-12-31

To investigate the potential effect of aged engineered nanoparticles (a-ENPs) on sludge digestion performance, 150L pilot anaerobic digesters (AD) were fed with a blend of primary and waste activated sludge spiked either with a mixture of silver oxide, titanium dioxide and zinc oxide or a mixture of their equivalent bulk metal salts to achieve a target concentration of 250, 2000, and 2800mgkg -1 dry weight, respectively. Volatile fatty acids (VFA) were 1.2 times higher in the spiked digesters and significantly different (p=0.05) from the control conditions. Specifically, isovaleric acid concentration was 2 times lower in the control digester compared to the spiked digesters, whereas hydrogen sulfide was 2 times lower in the ENPs spiked digester indicating inhibitory effect on sulfate reducing microorganisms. Based on the ether-linked isoprenoids concentration, the total abundance of methanogens was 1.4 times lower in the ENPs spiked digester than in the control and metal salt spiked digesters. Pyrosequencing indicated 80% decrease in abundance and diversity of methanogens in ENPs spiked digester compared to the control digester. Methanosarcina acetivorans and Methanosarcina barkeri were identified as nano-tolerant as their relative abundance increased by a factor of 6 and 11, respectively, compared to the other digesters. The results further provide compelling evidence on the resilience of Fusobacteria, Actinobacteria and the Trojan horse-like effect of ENPs which offered a competitive advantage to some organisms while reducing microbial abundance and diversity. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Effects of cottonseed meal supplementation time on ruminal fermentation and forage intake by Holstein steers fed fescue hay.

PubMed

Judkins, M B; Krysl, L J; Barton, R K; Holcombe, D W; Gunter, S A; Broesder, J T

1991-09-01

Four ruminally cannulated Holstein steers (average BW 303 kg) were used in a 4 x 4 Latin square design digestion trial to study the influence of daily cottonseed meal (CSM; 1.6 g of CP/kg of BW) supplementation time on forage intake and ruminal fluid kinetics and fermentation. Steers were housed individually in tie stalls and were fed chopped fescue hay on an ad libitum basis at 0600 and 1400. Treatments were 1) control, grass hay only (CON) and grass hay and CSM fed once daily at 2) 0600 (EAM) 3) 1000 (MAM), or 4) 1400 (PM). Ruminal NH3 N concentrations reflected a time of supplementation x sampling time interaction (P less than .05); CON steers had the lowest (P less than .05) ruminal NH3 N concentrations at all times other than at 0600, 1000, 1200, and 2400, when they did not differ (P greater than .05) from at least one of the supplemented groups. Forage intake, ratio of bacterial purine:N, rate of DM and NDF disappearance, and ruminal fluid kinetics were not influenced (P greater than .05) by supplementation time. Total ruminal VFA differed (P less than .05) between CON and supplemented steers, as well as among supplemented steers (linear and quadratic effects P less than .05). Acetate, propionate, and valerate proportions were influenced (P less than .05) by a sampling time X supplementation time interaction. Under the conditions of this study, greater peak ammonia concentrations with morning supplementation than with afternoon supplementation did not stimulate ruminal fermentation or rate of NDF disappearance.

Ruminal pH predictions for beef cattle: Comparative evaluation of current models.

PubMed

Sarhan, M A; Beauchemin, K A

2015-04-01

This study evaluated 8 empirical models for their ability to accurately predict mean ruminal pH in beef cattle fed a wide range of diets. Models tested that use physically effective fiber (peNDF) as a dependent variable were Pitt et al. (1996, PIT), Mertens (1997, MER), Fox et al. (2004, FOX), Zebeli et al. (2006, ZB6), and Zebeli et al. (2008, ZB8), and those that use rumen VFA were Tamminga and Van Vuuren (1988, TAM), Lescoat and Sauvant (1995, LES), and Allen (1997, ALL). A data set of 65 published papers (231 treatment means) for beef cattle was assembled that included information on animal characteristics, diet composition, and ruminal fermentation and mean pH. Model evaluations were based on mean square prediction error (MSPE), concordance correlation coefficient (CCC), and regression analysis. The prediction potential of the models varied with low root MSPE (RMSPE) values of 4.94% and 5.37% for PIT and FOX, RMSPE values of 9.66% and 12.55% for ZB6 and MER, and intermediate RMSPE values of 5.66% to 6.26% for the other models. For PIT and FOX, with the lowest RMSPE, approximately 96% of MSPE was due to random error, whereas for ZB6 and MER, with the highest RMSPE, 15.85% and 23.42% of MSPE, respectively, was due to linear bias, and 37.19% and 60.12% of the error, respectively, was due to deviation of the regression slope from unity. The CCC was greatest for PIT (0.67) and FOX (0.62), followed by 0.60 for LES and TAM, 0.52 for ZB8, 0.39 for MER, 0.34 for ALL, and 0.22 for ZB6. Residuals plotted against model-predicted values showed linear bias (P < 0.001) for all models except PIT (P = 0.976) and FOX (P = 0.054) and mean bias (P < 0.001) except for FOX (P = 0.293), LES (P = 0.215), and TAM (P = 0.119). The study showed that the empirical models PIT and FOX, based on peNDF, and LES and TAM, based on VFA, are preferred over the others for prediction of mean ruminal pH in beef cattle fed a wide range of diets. Several animal (BW and intake), diet (forage and OM contents), and ruminal (ammonia and acetate concentrations) factors were (P < 0.001) related to the residuals for each model. We conclude that the accuracy of prediction of mean ruminal pH was relatively low for all extant models. Consideration of factors in addition to peNDF and total VFA, as well as the use of data from studies with continuous measurement of ruminal pH over 24 h or more, would be useful in the development of improved models for predicting ruminal pH in beef cattle.

Effects of exogenous xylanase on performance, nutrient digestibility, volatile fatty acid production and digestive tract thermal profiles of broilers fed on wheat- or maize-based diet.

PubMed

Masey-O'Neill, H V; Singh, M; Cowieson, A J

2014-01-01

1. A previous experiment reported that caecal temperature was negatively correlated with d 49 feed conversion ratio (FCR). This increased temperature in the caeca may indicate a prebiotic effect. An experiment was designed to investigate whether caecal temperature was affected in diets based on maize and whether other portions of the tract were affected. 2. A total of 25 Ross 308-d-old male broilers were allocated to each of 8 replicate pens per treatment. Treatments followed a 2 × 3 factorial design: two diets based on wheat or maize and three levels of enzyme addition, 0, 16 000 or 32 000 BXU/kg. Growth performance was assessed between d 1 and 49. Digestibility measurements were taken at d 28 and 49. On d 49, the excised small and large intestine of each bird was thermally imaged, weighed and volatile fatty acids (VFA) measured. 3. On d 28 and d 49, birds on the maize diets had higher feed intake and weight gain than those offered wheat diets. Additionally, on d 28, birds that received the maize diet had lower FCR than those offered the wheat diet. Enzyme improved FCR at d 49, independently of cereal. On d 28, enzyme improved the coefficient of apparent ileal DM digestibility and the coefficient of apparent ileal nitrogen digestibility. Enzyme only improved apparent ileal digestible energy in wheat-based diets (interactive term). On d 49, all digestibility parameters were improved by enzyme. Enzyme increased gizzard weight in maize-fed birds and the caeca of those fed wheat were heavier. The higher enzyme dose decreased duodenal temperature. In summary of VFA data, wheat-based diets produced more total VFAs and the total amount also increased with enzyme. 4. It appears from this study that there is equal potential in both wheat and maize diets for xylanase to improve performance of broilers probably through different mechanisms.

Feeding a diet containing resistant potato starch influences gastrointestinal tract traits and growth performance of weaned pigs.

PubMed

Heo, J M; Agyekum, A K; Yin, Y L; Rideout, T C; Nyachoti, C M

2014-09-01

The aim was to evaluate the effects of feeding resistant potato starch (RPS) as a natural source of resistant starch to weaned pigs for 28 d immediately after weaning. Sixty piglets (Yorkshire-Landrace × Duroc) weaned at 21 ± 2 d (1:1 male:female) with an initial BW of 7.2 ± 0.78 kg were assigned in a completely randomized design to 1 of 5 dietary treatments to give 6 observations per treatment and 2 pigs per pen. Dietary treatments consisted of a negative control corn-soybean meal-wheat-wheat middlings-based diet (NC; no antimicrobial agents added) or the NC supplemented with RPS either as powder or in capsules and each included at 0.5 or 1.0% as a top-dressing on each day. Diets were formulated to meet 1998 NRC specifications. Pigs were offered the experimental diets on an ad libitum basis for 28 d and water was available at all times. The ADG, ADFI, and G:F were determined weekly. Fecal score was determined daily for 14 d after weaning. At the conclusion of study, 1 pig from each pen was randomly selected and euthanized (n = 6 per treatment) to determine visceral organ weight, digesta pH, VFA, and ammonia N (NH3-N) concentrations. Resistant potato starch supplementation improved (P < 0.001) fecal score, and pigs offered 1.0% RPS had more solid feces (P < 0.05) than those offered 0.5% RPS during the first 14 d after weaning, independent of the form of RPS. Resistant potato starch supplementation decreased (P < 0.05) ileal and cecal digesta pH regardless of the levels of RPS or mode of delivery. The total VFA concentrations in cecal digesta were greater (P < 0.05) but the molar proportion of branched-chain fatty acids were lower (P < 0.05) for pigs fed the RPS-containing diets compared with those fed the NC, irrespective of the RPS levels or the form of RPS. However, there were no differences (P > 0.10) in visceral organ weights, growth performance, and digestibilities of DM, CP, Ca, and P among treatments. The results of this experiment indicate that supplementing a weaner pig diet with at least 0.5% RPS independent of mode of delivery has the potential to enhance outcomes characteristic of a functional gut in weaned pigs without adverse effects on growth.

Influence of feeding alternative fiber sources on the gastrointestinal fermentation, digestive enzyme activities and mucosa morphology of growing Greylag geese.

PubMed

He, L W; Meng, Q X; Li, D Y; Zhang, Y W; Ren, L P

2015-10-01

The objective of this trial was to study the influence of dietary fiber sources on the gastrointestinal fermentation, digestive enzyme activity, and mucosa morphology of growing Greylag geese. In total, 240 Greylag geese (28-day-old) were allocated to 4 treatments (15 pens/treatment) differing in dietary fiber source: corn straw silage (CSS group), steam-exploded corn straw (SECS group), steam-exploded wheat straw (SEWS group), or steam-exploded rice straw (SERS group). At 112 days of age, 15 birds per group were euthanized to collect samples. No difference (P > 0.05) was found on all the gastrointestinal pH values and ammonia-nitrogen concentrations between the groups. The CSS and SERS groups had a lower (P < 0.05) proportion of acetic acid in the gizzard than the SECS and SEWS groups. The CSS group had a higher VFA concentration in the jejunum (P < 0.05) and acetic acid proportion (P < 0.01) in the ceca, and a lower (P < 0.01) butyric acid proportion than the other groups except for the SECS group. The SECS group had a higher (P < 0.01) acetic acid proportion and lower (P < 0.05) proportions of propionic acid and valeric acid in the ceca than the SEWS and SERS groups. Different fiber sources resulted in different VFA profiles, especially in the gizzard and ceca. Almost all gastrointestinal protease activities of the CSS group were higher (P < 0.05) than the other groups, along with lower (P < 0.01) amylase activities in the duodenum, jejunum, ileum, and ceca. Lipase activity in proventriculus was highest (P < 0.01) in the SEWS group and its cecal activity was lower (P < 0.01) in the SECS and SEWS groups than the CSS and SERS groups with a higher (P < 0.01) lipase activity in the CSS group than the SERS group. The SECS and SERS groups had a higher cellulase activity in the ceca than the CSS and SEWS groups, with a higher (P < 0.01) rectal cellulase activity in the SERS group than the other groups. There was no significant effect (P > 0.05) on the intestinal mucosa morphology. These results suggest that corn straw silage improves protein digestion while steam-exploded straw provides more energy. © 2015 Poultry Science Association Inc.

Effect of Ensiled Mulberry Leaves and Sun-Dried Mulberry Fruit Pomace on Finishing Steer Growth Performance, Blood Biochemical Parameters, and Carcass Characteristics

PubMed Central

Zhou, Zhenming; Zhou, Bo; Ren, Liping; Meng, Qingxiang

2014-01-01

Fifty-one Simmental crossbred steers (357.0±16.5 kg) were used to compare a standard total mix ration (TMR) with variants on animal performance, ruminal fermentation, blood biochemical parameters, and carcass characteristics. Corn grain and cotton seed meal were partially replaced by ensiled mulberry leaves (EML) or sun-dried mulberry fruit pomace (SMFP). Experimental diets had similar amounts of crude protein (CP), acid detergent fiber (ADF), and metabolizable energy (ME). Animals were divided into three groups: control group (CONT), 8% EML group, and 6.3% SMFP group. Performance, including average daily weight gain (ADG), and dry matter intake (DMI), was measured. Blood and rumen samples were collected at the end of the experiment (16 weeks). There were no differences in final body weight (P = 0.743), ADG (P = 0.425), DMI (P = 0.642), or ADG/DMI (P = 0.236) between the groups. There were no differences (P = 0.2024) in rumen pH values; ammonia N was lower (P = 0.0076) in SMFP than in the EML and CONT groups. There were differences in the concentrations of total and individual volatile fatty acids, while no differences were determined in blood biochemical parameters (i.e., plasma glucose, urea concentrations, triglycerides, total protein, insulin, IgG, alanine transaminase, and aspartate aminotransferase, P ≥ 0.098). No differences were observed in carcass characteristics (P ≥ 0.513), tenderness (P = 0.844), adipose and lean color values (P ≥ 0.149), and chemical composition (P ≥ 0.400); however, intramuscular fat was lower in the EML and SMFP groups compared to the CONT animals (P = 0.034). In conclusion, diets supplemented with these two mulberry products in an isocaloric and isonitrogenous manner have similar effects to corn grain and cotton seed meals on steer performance, blood biochemical parameters and carcass characteristics, with the exception of ruminal VFA concentrations and lower intramuscular fat content. PMID:24427304

Efficient anaerobic mono-digestion of N-rich slaughterhouse waste: influence of ammonia, temperature and trace elements.

PubMed

Ortner, Markus; Leitzinger, Kerstin; Skupien, Sören; Bochmann, Günther; Fuchs, Werner

2014-12-01

Three mono-digestion experiments treating slaughterhouse waste with high TKN concentration (∼11g/kg) were applied in lab-scale at mesophilic and psychrophilic conditions to study the impact of high ammonia concentrations and additives. Precipitation of sulphur by addition of ferrous chloride did not influence process behaviour, whereas supplementation of trace elements significantly improved process stability by reducing volatile fatty acid concentration towards zero. The limit of NH4-N concentration causing a rise of VFAs to 19,000mg/l and reduction of methane by 25% was found between 7.7 and 9.1g/kg which correspond to NH3 concentrations of 830-1060mg/l. Psychrophilic operation (25°C) lowered inhibitory NH3 concentration to 140mg/l, but process performance was stable only at low OLR of 0.4kgVS/m(3)d. Robust performance at highest possible NH4-N concentration (7.7g/kg), low VFA accumulation and satisfying methane yield of about 280Nm(3)/t COD was observed at OLR of 2.5kgVS/m(3)d at 37°C. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of dietary crude glycerol level on ruminal fermentation in continuous culture and growth performance of beef calves.

PubMed

Ramos, M H; Kerley, M S

2012-03-01

Continuous culture and in vivo experiments were conducted to measure changes in ruminal fermentation and animal performance when crude glycerol was added to diets. For the continuous culture experiment (n = 6), diets consisted of 4 levels of crude glycerol (0, 5, 10, and 20%) that replaced corn grain. Dry matter and OM digestibility decreased linearly (P < 0.05) when crude glycerol increased in the diet, and no effect (P = 0.20 and 0.65, respectively) was observed for CP and NDF digestibility. Total VFA concentration and ammonia did not change (P > 0.05) due to crude glycerol level. Microbial efficiency increased quadratically (P = 0.012) as crude glycerol increased, whereas microbial N flow did not differ (P = 0.36) among treatments. As crude glycerol increased in the diet, crude glycerol digestibility decreased (P < 0.05). Seventy-two crossbred steer calves (250 ± 2.0 kg) were assigned to 4 treatments: 0, 5, 10, and 20% crude glycerol that replaced corn grain. Animals were fed for a total of 150 d. No differences (P = 0.08) between treatments were measured for DMI. Average daily gain and GF responded quadratically (P < 0.05), with 10% crude glycerol resulting in the greatest values. In the second in vivo experiment, 100 crossbred steer calves (300 ± 2.0 kg) were assigned to 5 treatments: 0, 5, 10, 12.5, or 15% crude glycerol replaced corn grain. Calves were fed for a total of 135 d. No significant differences (P > 0.05) were measured in growth performance. For Exp. 3, one hundred heifer calves (270 ± 2.0 kg) were assigned to 4 treatments: 0, 5, 10, or 20% crude glycerol that replaced hay. No differences (P > 0.05) were measured in animal performance. We concluded that crude glycerol addition to a diet did not negatively affect ruminal fermentation, and addition of up to 20% in concentrate and hay-based diets should not affect performance or carcass characteristics.

Aerobic performance and body composition changes during military service

PubMed Central

Mikkola, Ilona; Keinänen-Kiukaanniemi, Sirkka; Jokelainen, Jari; Peitso, Ari; Härkönen, Pirjo; Timonen, Markku; Ikäheimo, Tiina

2012-01-01

Objective To examine the association between aerobic performance and body composition changes by body mass index (BMI). Design 6–12 months’ follow-up during military service. Setting Conscripts entering military service in 2005 in Sodankylä Jaeger Brigade (Finland). Subjects 945 men (19 years, SD 1 years). Main outcome measures Height, weight, waist circumference, BMI, and aerobic performance (Cooper test) were recorded. Body composition was measured by bioelectrical impedance analysis (BIA). The measured parameters were fat mass (FM), fat free mass (FFM), and visceral fat area (VFA). All the measurements were performed at the beginning and end of service. Results On average, the military training period improved the running distance by 6.8% (169 m, p < 0.001) and the improvements were more pronounced in overweight (223.9 m/9.5%, p < 0.001) and obese (273.3 m/13.6 %, p < 0.001) conscripts. A strong inverse correlation between aerobic performance and body composition changes was observed, especially for weight (r = –0.305, p < 0.001) and VFA (r = –0.465, p < 0.001). A significant association between aerobic performance and changes in weight (p < 0.001), waist circumference (p < 0.001), FM (p < 0.001), and VFA (p < 0.001) by BMI was detected. The associated decrease in weight, waist circumference, FM, and VFA with improved aerobic performance was more substantial between overweight and obese compared with normal-weight subjects. Conclusions Favourable changes in body composition are associated with improved aerobic performance during a physical training period such as military service. These findings are pronounced among overweight and obese men and can be applied at the population level in reducing obesity and co-morbidities. PMID:22643154

Replication study of 15 recently published Loci for body fat distribution in the Japanese population.

PubMed

Hotta, Kikuko; Kitamoto, Aya; Kitamoto, Takuya; Mizusawa, Seiho; Teranishi, Hajime; So, Rina; Matsuo, Tomoaki; Nakata, Yoshio; Hyogo, Hideyuki; Ochi, Hidenori; Nakamura, Takahiro; Kamohara, Seika; Miyatake, Nobuyuki; Kotani, Kazuaki; Itoh, Naoto; Mineo, Ikuo; Wada, Jun; Yoneda, Masato; Nakajima, Atsushi; Funahashi, Tohru; Miyazaki, Shigeru; Tokunaga, Katsuto; Masuzaki, Hiroaki; Ueno, Takato; Chayama, Kazuaki; Hamaguchi, Kazuyuki; Yamada, Kentaro; Hanafusa, Toshiaki; Oikawa, Shinichi; Sakata, Toshiie; Tanaka, Kiyoji; Matsuzawa, Yuji; Nakao, Kazuwa; Sekine, Akihiro

2013-01-01

Visceral fat accumulation plays an integral role in morbidity and mortality rates by increasing the risk of developing metabolic disorders such as type 2 diabetes, dyslipidemia, and hypertension. New genetic loci associated with fat distribution, measured by waist-hip ratios and computed tomography (CT), have recently been identified by genome-wide association studies in European-descent populations. This study used CT to investigate whether single nucleotide polymorphisms (SNPs) that confer susceptibility to fat distribution are associated with visceral fat area (VFA) and subcutaneous fat area (SFA) in the Japanese population. We measured the VFAs and SFAs of 1424 obese Japanese subjects (BMI≥25 kg/m(2), 635 men and 789 women) that were genotyped at 15 SNPs, namely, TBX15 rs984222, DNM3 rs1011731, LYPLAL1 rs4846567, GRB14 rs10195252, NISCH rs6784615, ADAMTS9 rs6795735, CPEB4 rs6861681, LY86 rs1294421, VEGFA rs6905288, RSPO3 rs9491696, NFE2L3 rs1055144, ITPR2 rs718314, HOXC13 rs1443512, ZNRF3 rs4823006 and THNSL2 rs1659258. The G-allele of LYPLAL1 rs4846567 was borderline associated with an increased ratio of VFA to SFA (V/S ratio; p= 0.0020). LYPLAL1 rs4846567 had a stronger effect on the V/S ratio in women (p= 0.0078) than in men (p= 0.12); however, neither result was significant after Bonferroni correction for multiple comparisons. NISCH rs6784615 was nominally associated with increased VFA (p=0.040) and V/S ratio (p= 0.020). The other SNPs analyzed were not significantly associated with body mass index (BMI), VFA, or SFA. Our results suggest that LYPLAL1 rs4846567 and NISCH rs6784615 may influence fat distribution in the Japanese population.

Enhanced biological phosphorus removal in a sequencing batch reactor using propionate as the sole carbon source.

PubMed

Pijuan, M; Saunders, A M; Guisasola, A; Baeza, J A; Casas, C; Blackall, L L

2004-01-05

An enhanced biological phosphorus removal (EBPR) system was developed in a sequencing batch reactor (SBR) using propionate as the sole carbon source. The microbial community was followed using fluorescence in situ hybridization (FISH) techniques and Candidatus 'Accumulibacter phosphatis' were quantified from the start up of the reactor until steady state. A series of SBR cycle studies was performed when 55% of the SBR biomass was Accumulibacter, a confirmed polyphosphate accumulating organism (PAO) and when Candidatus 'Competibacter phosphatis', a confirmed glycogen-accumulating organism (GAO), was essentially undetectable. These experiments evaluated two different carbon sources (propionate and acetate), and in every case, two different P-release rates were detected. The highest rate took place while there was volatile fatty acid (VFA) in the mixed liquor, and after the VFA was depleted a second P-release rate was observed. This second rate was very similar to the one detected in experiments performed without added VFA.A kinetic and stoichiometric model developed as a modification of Activated Sludge Model 2 (ASM2) including glycogen economy, was fitted to the experimental profiles. The validation and calibration of this model was carried out with the cycle study experiments performed using both VFAs. The effect of pH from 6.5 to 8.0 on anaerobic P-release and VFA-uptake and aerobic P-uptake was also studied using propionate. The optimal overall working pH was around 7.5. This is the first study of the microbial community involved in EBPR developed with propionate as a sole carbon source along with detailed process performance investigations of the propionate-utilizing PAOs. Copyright 2003 Wiley Periodicals, Inc.

The impact of reliable prebolus T 1 measurements or a fixed T 1 value in the assessment of glioma patients with dynamic contrast enhancing MRI.

PubMed

Tietze, Anna; Mouridsen, Kim; Mikkelsen, Irene Klærke

2015-06-01

Accurate quantification of hemodynamic parameters using dynamic contrast enhanced (DCE) MRI requires a measurement of tissue T 1 prior to contrast injection (T 1). We evaluate (i) T 1 estimation using the variable flip angle (VFA) and the saturation recovery (SR) techniques and (ii) investigate if accurate estimation of DCE parameters outperform a time-saving approach with a predefined T 1 value when differentiating high- from low-grade gliomas. The accuracy and precision of T 1 measurements, acquired by VFA and SR, were investigated by computer simulations and in glioma patients using an equivalence test (p > 0.05 showing significant difference). The permeability measure, K trans, cerebral blood flow (CBF), and - volume, V p, were calculated in 42 glioma patients, using fixed T 1 of 1500 ms or an individual T 1 measurement, using SR. The areas under the receiver operating characteristic curves (AUCs) were used as measures for accuracy to differentiate tumor grade. The T 1 values obtained by VFA showed larger variation compared to those obtained using SR both in the digital phantom and the human data (p > 0.05). Although a fixed T 1 introduced a bias into the DCE calculation, this had only minor impact on the accuracy differentiating high-grade from low-grade gliomas, (AUCfix = 0.906 and AUCind = 0.884 for K trans; AUCfix = 0.863 and AUCind = 0.856 for V p; p for AUC comparison > 0.05). T 1 measurements by VFA were less precise, and the SR method is preferable, when accurate parameter estimation is required. Semiquantitative DCE values, based on predefined T 1 values, were sufficient to perform tumor grading in our study.

Treatment of fruit-juice industry wastewater in a two-stage anaerobic hybrid (AH) reactor system followed by a sequencing batch reactor (SBR).

PubMed

Tawfik, A; El-Kamah, H

2012-01-01

This study has been carried out to assess the performance of a combined system consisting of an anaerobic hybrid (AH) reactor followed by a sequencing batch reactor (SBR) for treatment of fruit-juice industry wastewater at a temperature of 26 degrees C. Three experimental runs were conducted in this investigation. In the first experiment, a single-stage AH reactor was operated at a hydraulic retention time (HRT) of 10.2 h and organic loading rate (OLR) of 11.8 kg COD m(-3) d(-1). The reactor achieved a removal efficiency of 42% for chemical oxygen demand (COD), 50.8% for biochemical oxygen demand (BOD5), 50.3% for volatile fatty acids (VFA) and 56.4% for total suspended solids (TSS). In the second experiment, two AH reactors connected in series achieved a higher removal efficiency for COD (67.4%), BOD5 (77%), and TSS (71.5%) at a total HRT of 20 h and an OLR of 5.9 kg COD m(-3) d(-1). For removal of the remaining portions of COD, BOD5 and TSS from the effluent of the two-stage AH system, a sequencing batch reactor (SBR) was investigated as a post-treatment unit. The reactor achieved a substantial reduction in total COD, resulting in an average effluent concentration of 50 mg L(-1) at an HRT of 11 h and OLR of 5.3 kg COD m(-3) d(-1). Almost complete removal of total BOD5 and oil and grease was achieved, i.e. 10 mg L(-1) and 1.2 mg L(-1), respectively, remained in the final effluent of the SBR.

Effects of dietary supplementation with alkyl polyglycoside, a nonionic surfactant, on nutrient digestion and ruminal fermentation in goats.

PubMed

Yuan, Z Q; Tang, S X; Zeng, B; Wang, M; Tan, Z L; Sun, Z H; Zhou, C S; Han, X F; Bamikole, M A

2010-12-01

The effects of dietary alkyl polyglycoside [APG, a nonionic surfactant (NIS), derived from a reaction of corn starch glucose and a natural fatty alcohol] inclusion on digestion of nutrients and ruminal fermentation in goats were examined in a 4 × 4 Latin square design using 4 ruminally and duodenally cannulated wethers (mean BW: 19.5 ± 0.8 kg). The animals were assigned to 4 dietary treatments of APG supplementation at 0, 3, 6, and 12 g/kg of DM diets and were designated as control, APG3, APG6, and APG12, respectively. The results showed that dietary APG inclusion tended to increase the intestinal digestibility of OM (linear, P = 0.09) and NDF (linear, P = 0.1), and quadratically increased (P ≤ 0.02) total tract digestibility of OM and NDF, the duodenal microbial N flow, and efficiency of microbial protein synthesis. The true ruminal digestibility and apparent total tract digestibility of N quadratically increased (P < 0.01) with increasing dietary APG. The ruminal pH values were not affected by dietary APG inclusion (P > 0.05), but the concentration of NH(3)-N (P < 0.01) and total VFA (linear and quadratic, P < 0.01) increased in the rumen fluid. Dietary APG inclusion also increased the activities of ruminal carboxymethyl cellulase (quadratic, P < 0.01) and xylanase (linear and quadratic, P < 0.01). It is concluded that APG is a potential feed additive that can be used in ruminant production; 6 g/kg in the total mixed rations for goats is recommended. It is necessary to validate the effectiveness of dietary APG inclusion in ruminant diets with more animals in further studies.

Feeding distillers' grains, soybean hulls, or a mixture of both to cows as a forage replacement: Effects on intake, digestibility, and ruminal fermentation characteristics.

PubMed

Smith, W B; Coffey, K P; Rhein, R T; Kegley, E B; Philipp, D; Powell, J G; Caldwell, J D; Young, A N

2017-08-01

Coproduct feedstuffs offer a unique and potentially profitable avenue for cattle feeding strategies. However, research is lacking in the evaluation of varying coproducts on ruminal fermentation and digestive characteristics when included as the major component of the diet of cows. Our objective was to determine the effect of coproduct feedstuffs as a forage replacement on digestive and fermentative characteristics of cows. Eight ruminally fistulated cows (672 ± 32.0 kg initial BW and approximately 9 yr of age) were stratified by BW and randomly allocated to 1 of 4 diets (2 cows∙diet∙period) in a 2-period study: soybean hulls (SH), distillers' dried grains with solubles (DG), an isoenergetic mixture of soybean hulls and distillers' dried grains with solubles (MX), or ad libitum hay plus 0.9 kg/d of an isoenergetic mixture of soybean hulls and distillers' dried grains with solubles (HY). Diets were formulated to meet the ME requirements of a similar, companion study. Coproduct amounts were increased over a 14-d period. This was followed by a 14-d adaptation to diet and facilities and 5 d of total fecal collections. On the final day of fecal collections, rumen fluid was sampled immediately prior to feeding and 2, 4, 6, 8, 10 and 12 h after feeding for measurement of rumen VFA and ammonia concentrations. Intake of DM and OM was not different ( ≥ 0.28) among treatments, but digestibilities of DM, OM, NDF, and ADF were improved ( < 0.05) by coproduct feeding and by MX vs. the mean of SH and DG. Ruminal DM and OM fill were greater ( < 0.05) for cows offered HY than for cows offered the coproduct diets, greater for cows offered SH than for cows offered DG, and for the mean of SH and DG vs. MX. Ruminal retention time was greater ( < 0.05) for HY vs. the coproduct diets and for SH vs. DG. Apparent N absorption tended ( < 0.10) to be greater for cows offered the coproduct diets than for cows offered HY and greater for cows offered DG than for cows offered SH. Total VFA averaged across sampling times were greatest ( < 0.05) for cows offered SH, and ruminal ammonia N was greatest ( < 0.05) for cows offered either DG or MX at all sampling times. Based on these data, coproduct feedstuffs may be fed to meet the energy requirement of cows without negative effects on digestion or ruminal fermentation.

A study on relationship between elderly sarcopenia and inflammatory factors IL-6 and TNF-α.

PubMed

Bian, Ai-Lin; Hu, Hui-Ying; Rong, Yu-Dong; Wang, Jian; Wang, Jun-Xiong; Zhou, Xin-Zi

2017-07-12

This report aims to study the relationship between sarcopenia of elderly in community and inflammatory factors IL-6 and TNF-α. A total of 441 elders who undertook physical examinations were included into this study. The age of these subjects were >60, in which 235 subjects were male and 206 subjects were female. According to the diagnostic standards of sarcopenia set by EWGSOP and AWGS, these subjects were divided into two groups: sarcopenia, and non-sarcopenia groups. The living habits, disease status, biochemical indexes, and levels of IL-6 and TNF-α of these subjects were investigated. The morbidity rate of sarcopenia was 17.02% in male subjects and 18.9% in female subjects. In elderly subjects >80 years old, morbidity rate was 25.3% in male subjects and 35.1% in female subjects. The history of smoking in patients with sarcopenia was long, and their regular exercise history was short (P < 0.01). Furthermore, differences in handgrip strength (HG), fat-free mass (FFM), bone mineral content (BMC), plasma albumin (ALB) and serum creatinine (Cr), and body fat content (FAT) in patients between the sarcopenia and non-sarcopenia groups were statistically significant (P < 0.05). Moreover, differences in IL-6 and TNF-α levels between these two groups were statistically significant (P < 0.05). In addition, BMI was positively correlated to TNF-α levels, and ALB was negatively correlated to IL-6; while BMI and VFA were positively correlated to TNF-α levels, and SMM, HDL-C, Hb, HG were negatively correlated to IL-6 level (P < 0.05). Multiple linear regression analysis suggested plasma ALB and BMI were the independent risk factors of TNF-α, while VFA was the independent risk factor of IL-6. The onset of sarcopenia was associated with poor exercise habits, disease history, and nutritional status. The emergence of sarcopenia was accompanied by increased levels of inflammation factors TNF-α and IL-6. Plasma albumin, BMI, and VFA were inflammatory factor predictors of TNF and IL-6.

Effects of sodium hydroxide treatment of dried distillers' grains on digestibility, ruminal metabolism, and metabolic acidosis of feedlot steers.

PubMed

Freitas, T B; Relling, A E; Pedreira, M S; Santana Junior, H A; Felix, T L

2016-02-01

The objectives were to determine the optimum inclusion of NaOH necessary to buffer the acidity of dried distillers' grains with solubles (DDGS) and its effects on digestibility, ruminal metabolism, and metabolic acidosis in feedlot steers. Rumen cannulated Angus-crossed steers were blocked by BW (small: 555 ± 42 kg initial BW, = 4; large: 703 ± 85 kg initial BW, = 4) over four 21-d periods in a replicated 4 × 4 Latin square design. Steers were assigned to 1 of 4 dietary treatments: 1) 50% untreated DDGS, 2) 50% DDGS treated with 0.5% (DM basis) sodium hydroxide (NaOH), 3) 50% DDGS treated with 1.0% (DM basis) NaOH, and 4) 50% DDGS treated with 1.5% (DM basis) NaOH. The remainder of the diets, on a DM basis, was composed of 20% corn silage, 20% dry-rolled corn, and 10% supplement. Ruminal pH was not affected by treatments ( = 0.56) or by a treatment × time interaction ( = 0.15). In situ NDF and ruminal DM disappearance did not differ ( ≥ 0.49 and ≥ 0.47, respectively) among treatments. Similar to in situ results, apparent total tract DM and NDF digestibility were not affected ( ≥ 0.33 and ≥ 0.21, respectively) by increasing NaOH inclusion in the diets. Urinary pH increased (linear, < 0.01) with increasing NaOH concentration in the diet. Blood pH was not affected ( ≥ 0.20), and blood total CO and partial pressure of CO were similar ( ≥ 0.56 and ≥ 0.17, respectively) as NaOH increased in the diet. Increasing NaOH in the diet did not affect ( ≥ 0.21) ruminal concentrations of total VFA. There were no linear ( = 0.20) or quadratic ( = 0.20) effects of treatment on ruminal acetate concentrations, nor was there a treatment × time interaction ( = 0.22) for acetate. Furthermore, there were no effects ( ≥ 0.90) of NaOH inclusion on ruminal propionate concentration. However, there was a quadratic response ( = 0.01) of ruminal butyrate concentrations as NaOH inclusion increased in the diet; ruminal butyrate concentrations were greatest with the 0.5 and 1.0% NaOH treatments of DDGS. In the current study, feeding DDGS treated with NaOH did not increase fiber digestibility nor was it necessary to alleviate a possible metabolic acidosis. Alkali treatment of DDGS did not increase average ruminal pH or blood pH.

Effects of nonstructural carbohydrates and protein sources on intake, apparent total tract digestibility, and ruminal metabolism in vivo and in vitro with high-concentrate beef cattle diets.

PubMed

Rotger, A; Ferret, A; Calsamiglia, S; Manteca, X

2006-05-01

To investigate the effects of synchronizing nonstructural carbohydrate (NSC) and protein degradation on intake and rumen microbial fermentation, four ruminally fistulated Holstein heifers (BW = 132.3 +/- 1.61 kg) fed high-concentrate diets were assigned to a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments studied in vivo and in vitro with a dual-flow continuous culture system. Two NSC sources (barley and corn) and 2 protein sources [soybean meal (SBM) and sunflower meal (SFM)] differing in their rate and extent of ruminal degradation were combined resulting in a synchronized rapid fermentation diet (barley-SFM), a synchronized slow fermentation diet (corn-SBM), and 2 unsynchronized diets with a rapidly and a slowly fermenting component (barley-SBM, and corn-SFM). In vitro, the fermentation profile was studied at a constant pH of 6.2, and at a variable pH with 12 h at pH 6.4 and 12 h at pH 5.8. Synchronization tended to result in greater true OM digestion (P = 0.072), VFA concentration (P = 0.067), and microbial N flow (P = 0.092) in vitro, but had no effects on in vivo fermentation pattern or on apparent total tract digestibility. The NSC source affected the efficiency of microbial protein synthesis in vitro, tending to be greater (P = 0.07) for barley-based diets, and in vivo, the NSC source tended to affect intake. Dry matter and OM intake tended to be greater (P > or = 0.06) for corn- than barley-based diets. Ammonia N concentration was lower in vitro (P = 0.006) and tended to be lower in vivo (P = 0.07) for corn- than barley-based diets. In vitro, pH could be reduced from 6.4 to 5.8 for 12 h/d without any effect on ruminal fermentation or microbial protein synthesis. In summary, ruminal synchronization seemed to have positive effects on in vitro fermentation, but in vivo recycling of endogenous N or intake differences could compensate for these effects.

Correlation between system performance and bacterial composition under varied mixing intensity in thermophilic anaerobic digestion of food waste.

PubMed

Ghanimeh, Sophia A; Al-Sanioura, Dana N; Saikaly, Pascal E; El-Fadel, Mutasem

2018-01-15

This study examines the stability and efficiency of thermophilic anaerobic digesters treating food waste under various mixing velocities (50-160 rpm). The results showed that high velocities (120 and 160 rpm) were harmful to the digestion process with 18-30% reduction in methane generation and 1.8 to 3.8 times increase in volatile fatty acids (VFA) concentrations, compared to mild mixing (50 and 80 rpm). Also, the removal rate of soluble COD dropped from 75 to 85% (at 50-80 rpm) to 20-59% (at 120-160 rpm). Similarly, interrupted mixing caused adverse impacts and led to near-failure conditions with excessive VFA accumulation (15.6 g l -1 ), negative removal rate of soluble COD and low methane generation (132 ml gVS -1 ). The best efficiency and stability were achieved under mild mixing (50 and 80 rpm). In particular, the 50 rpm stirring speed resulted in the highest methane generation (573 ml gVS -1 ). High-throughput sequencing of 16S rRNA genes revealed that the digesters were dominated by one bacterial genus (Petrotoga; phylym Thermotogae) at all mixing velocities except at 0 rpm, where the community was dominated by one bacterial genus (Anaerobaculum; phylum Synergistetes). The Petrotoga genus seems to have played a major role in the degradation of organic matter. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of soybean hull supplementation on rumen fermentation and digestibility in steers consuming freshly clipped, endophyte-infected tall fescue.

PubMed

Richards, C J; Pugh, R B; Waller, J C

2006-03-01

Six steers (288.6 +/- 2.1 kg of BW) fitted with rumen and duodenal cannulas were used in a crossover design to evaluate intake, rumen fermentation, and site of nutrient digestion of freshly clipped, endophyte-infected (E+) Kentucky 31 tall fescue with or without soybean hull (SH) supplementation at 0.60% of BW (OM basis). Steers were placed in metabolism units within an environmentally controlled room and provided with free-choice access to fresh forage, water, and a vitamin/mineral supplement. The spring growth of E+ tall fescue was harvested daily during the experiment. Supplement was fed at 0700 with approximately 65% of the estimated daily forage. To maintain a fresh forage supply, additional forage was stored in a cooler and fed at 1900. Periods were 21 d with 14 d of adaptation and 7 d of digesta sample collection. Chromic oxide was used as a marker of duodenal digesta flow. Duodenal samples were taken 4 times daily with times shifting by 1 h each day to represent all 24 h of a day. Treatments were considered significant at P < 0.05. Supplementation of SH decreased forage OM intake from 1.64 to 1.41% of BW but increased total OM intake from 1.64 to 2.01% of BW. Apparent percentages (53.1%) and quantities (2,786 g/d) of rumen OM disappearance were not affected by supplementation. Percentages of total tract OM disappearance were not different (70.8%). Percentages of apparent rumen NDF disappearance also were not different (65.6%). Percentages of N disappearance were not different. Supplementation of SH resulted in increased total N (34.1 g/d) and microbial N (17.1 g/d) flowing to the duodenum. Rumen pH (6.5) was not affected, and rumen ammonia concentrations exhibited a time x treatment interaction in which SH decreased ammonia for 12 h after supplementation. Total VFA concentrations (103.9 mM) were unaffected. Liquid dilution rate (12.7%/h) and rumen OM fill (4.3 kg) were not different between treatments. Supplementation of SH at a rate of 0.60% of BW (OM basis) to calves consuming fresh E+ tall fescue decreased forage consumption but resulted in greater total intake, greater flow of N to the duodenum, and increased total tract OM disappearance.

Gas-liquid chromatography in the diagnosis of anaerobic infections: a three year experience.

PubMed Central

Watt, B; Geddes, P A; Greenan, O A; Napier, S K; Mitchell, A

1982-01-01

Nearly two thousand clinical samples were examined by direct gas-liquid chromatography over a three year period. Absence of volatile fatty acids (VFAs) in the samples correlated well with negative culture results for anaerobic bacteria. In general the presence of acetic acid alone correlated well with the presence of aerobic organisms, whereas the presence of a mixture of VFAs correlated well with the presence of anaerobic organisms, either alone or in combination with aerobes. However a proportion of such VFA-positive samples gave no growth on culture. Swabs gave comparable results to samples of pus or exudates except that a higher proportion of the former were VFA-negative but culture positive. PMID:7096590

Archaeal community composition affects the function of anaerobic co-digesters in response to organic overload

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lerm, S.; Kleyboecker, A.; Miethling-Graff, R.

2012-03-15

Highlights: Black-Right-Pointing-Pointer Two types of methanogens are necessary to respond successfully to perturbation. Black-Right-Pointing-Pointer Diversity of methanogens correlates with the VFA concentration and methane yield. Black-Right-Pointing-Pointer Aggregates indicate tight spatial relationship between minerals and microorganisms. - Abstract: Microbial community diversity in two thermophilic laboratory-scale and three full-scale anaerobic co-digesters was analysed by genetic profiling based on PCR-amplified partial 16S rRNA genes. In parallel operated laboratory reactors a stepwise increase of the organic loading rate (OLR) resulted in a decrease of methane production and an accumulation of volatile fatty acids (VFAs). However, almost threefold different OLRs were necessary to inhibit themore » gas production in the reactors. During stable reactor performance, no significant differences in the bacterial community structures were detected, except for in the archaeal communities. Sequencing of archaeal PCR products revealed a dominance of the acetoclastic methanogen Methanosarcina thermophila, while hydrogenotrophic methanogens were of minor importance and differed additionally in their abundance between reactors. As a consequence of the perturbation, changes in bacterial and archaeal populations were observed. After organic overload, hydrogenotrophic methanogens (Methanospirillum hungatei and Methanoculleus receptaculi) became more dominant, especially in the reactor attributed by a higher OLR capacity. In addition, aggregates composed of mineral and organic layers formed during organic overload and indicated tight spatial relationships between minerals and microbial processes that may support de-acidification processes in over-acidified sludge. Comparative analyses of mesophilic stationary phase full-scale reactors additionally indicated a correlation between the diversity of methanogens and the VFA concentration combined with the methane yield. This study demonstrates that the coexistence of two types of methanogens, i.e. hydrogenotrophic and acetoclastic methanogens is necessary to respond successfully to perturbation and leads to stable process performance.« less

Effect of concentrate feeder design on performance, eating and animal behavior, welfare, ruminal health, and carcass quality in Holstein bulls fed high-concentrate diets.

PubMed

Verdú, M; Bach, A; Devant, M

2015-06-01

A total of 240 Holstein bulls (121 ± 2.0 kg initial BW; 99 ± 1.0 d of age), from 2 consecutive fattening cycles, were randomly allocated in 1 of 6 pens and assigned to 1 of the 3 treatments consisting of different concentrate feeder designs: a control feeder with 4 feeding spaces (CF), a feeder with less concentrate capacity (CFL), and a single-space feeder with lateral protections (SF). Each pen had a straw feeder and a drinker. All animals were fed a high-concentrate diet for ad libitum intake. Concentrate consumption was recorded daily using a computerized feeder, straw consumption was recorded weekly, and BW was recorded every 14 d. Animal behavior was registered on d 1, 3, 5, 8, and 14 and every 28 d by scan sampling. Eating behavior at concentrate feeders was filmed on d 12, 125, and 206. On d 7, 120, and 204, samples of rumen contents were collected for measurement of pH and VFA and blood samples were obtained to analyze NEFA, haptoglobin, glucose, and insulin. Animals were slaughtered after 223 d, and HCW and lesions of the rumen wall and liver were recorded. The accumulative concentrate consumption per animal tended (P = 0.09) to be greater with CF than with CFL and SF. Also, CV of concentrate consumption was greater (P < 0.01) for SF than for CF or CFL. However, feeder design did not influence the other performance and carcass data. Also, no differences among treatments in rumen wall evaluation and liver abscesses were observed. At 7 and 204 d of study, SF bulls had greater (P < 0.05) rumen pH compared with CF and CFL bulls. On d 7, the acetate to propionate ratio from SF was greater (P < 0.05) than for CFL or CF. At d 7, NEFA of SF were greater (P < 0.05) compared with CF and CFL. Bulls fed with CF have the greatest (P < 0.01) concentrate disappearance velocity followed by bulls fed with CFL and finally by bulls fed with SF, and this was associated with different feeding behaviors. Bulls on SF spent more time (P < 0.05) eating straw and exhibited fewer (P < 0.05) displacements at concentrate feeder than CF and CFL bulls. The CFL bulls exhibited (P < 0.01) more attempted mounts and tended (P = 0.10) to exhibit more completed mounts than CF bulls. In conclusion, both alternative feeder designs (CFL and SF) are good strategies to reduce total concentrate consumption without impairing performance, rumen health, or animal welfare in Holstein bulls fed high-concentrate diets. However, at the beginning, there was evidence that animals fed using SF had problems with adaptation.

Control of amphibious weed ipomoea (Ipomoea carnea) by utilizing it for the extraction of volatile fatty acids as energy precursors.

PubMed

Rafiq Kumar, M; Tauseef, S M; Abbasi, Tasneem; Abbasi, S A

2015-01-01

Volatile fatty acids (VFAs), comprising mainly of acetic acid and lesser quantities of propionic and butyric acids, are generated when zoomass or phytomass is acted upon by acidogenic and acetogenic microorganisms. VFAs can be utilized by methanogens under anaerobic conditions to generate flammable methane-carbon dioxide mixtures known as 'biogas'. Acting on the premise that this manner of VFA utilization for generating relatively clean energy can be easily accomplished in a controlled fashion in conventional biogas plants as well as higher-rate anaerobic digesters, we have carried out studies aimed to generate VFAs from the pernicious weed ipomoea (Ipomoea carnea). The VFA extraction was accomplished by a simple yet effective technology, appropriate for use even by laypersons. For this acid-phase reactors were set, to which measured quantities of ipomoea leaves were charged along with water inoculated with cow dung. The reactors were stirred intermittently. It was found that VFA production started within hours of the mixing of the reactants and peaked by the 10(th) or 11(th) day in all the reactors, effecting a conversion of over 10% of the biomass into VFAs. The reactor performance had good reproducibility and the process appeared easily controllable, frugal and robust.

Control of amphibious weed ipomoea (Ipomoea carnea) by utilizing it for the extraction of volatile fatty acids as energy precursors

PubMed Central

Rafiq Kumar, M.; Tauseef, S.M.; Abbasi, Tasneem; Abbasi, S.A.

2014-01-01

Volatile fatty acids (VFAs), comprising mainly of acetic acid and lesser quantities of propionic and butyric acids, are generated when zoomass or phytomass is acted upon by acidogenic and acetogenic microorganisms. VFAs can be utilized by methanogens under anaerobic conditions to generate flammable methane–carbon dioxide mixtures known as ‘biogas’. Acting on the premise that this manner of VFA utilization for generating relatively clean energy can be easily accomplished in a controlled fashion in conventional biogas plants as well as higher-rate anaerobic digesters, we have carried out studies aimed to generate VFAs from the pernicious weed ipomoea (Ipomoea carnea). The VFA extraction was accomplished by a simple yet effective technology, appropriate for use even by laypersons. For this acid-phase reactors were set, to which measured quantities of ipomoea leaves were charged along with water inoculated with cow dung. The reactors were stirred intermittently. It was found that VFA production started within hours of the mixing of the reactants and peaked by the 10th or 11th day in all the reactors, effecting a conversion of over 10% of the biomass into VFAs. The reactor performance had good reproducibility and the process appeared easily controllable, frugal and robust. PMID:25685545

Enhancement of volatile fatty acid production and biogas yield from food waste following sonication pretreatment.

PubMed

Liu, Nuo; Jiang, Jianguo; Yan, Feng; Gao, Yuchen; Meng, Yuan; Aihemaiti, Aikelaimu; Ju, Tongyao

2018-07-01

The positive effect of sonication on volatile fatty acid (VFA) and hydrogen production was investigated by batch experiments. Several sonication densities (2, 1.6, and 1.2 W/mL) and times (5, 10, and 15 min) were tested. The optimal sonication condition was ultrasonic density 2 W/mL and ultrasonic time 15 min (2-U15). The FW particle size larger than 50 μm (d > 50 μm) were more susceptible to the sonication treatment than the smaller particle size (d ≤ 50 μm). The SCOD increased and VS reduction accelerated under sonication treatment. The maximum VFA production and the highest proportion of hydrogen in the biogas increased 65.3% and 59.1%, respectively, under the optimal sonication conditions compared to the unsonicated batch. Moreover, a reduction of over 50% in the time required to reach its maximum production was also observed. Butyric acid fermentation type was obtained whether following sonication treatment or not. The composition of key microbial community differed under the various sonication conditions. The genera Clostridium and Parabacteroides are predominantly responsible for VFA generation and both were found to be abundant under the optimal condition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparison of laser ray-tracing and skiascopic ocular wavefront-sensing devices

PubMed Central

Bartsch, D-UG; Bessho, K; Gomez, L; Freeman, WR

2009-01-01

Purpose To compare two wavefront-sensing devices based on different principles. Methods Thirty-eight healthy eyes of 19 patients were measured five times in the reproducibility study. Twenty eyes of 10 patients were measured in the comparison study. The Tracey Visual Function Analyzer (VFA), based on the ray-tracing principle and the Nidek optical pathway difference (OPD)-Scan, based on the dynamic skiascopy principle were compared. Standard deviation (SD) of root mean square (RMS) errors was compared to verify the reproducibility. We evaluated RMS errors, Zernike terms and conventional refractive indexes (Sph, Cyl, Ax, and spherical equivalent). Results In RMS errors reading, both devices showed similar ratios of SD to the mean measurement value (VFA: 57.5±11.7%, OPD-Scan: 53.9±10.9%). Comparison on the same eye showed that almost all terms were significantly greater using the VFA than using the OPD-Scan. However, certain high spatial frequency aberrations (tetrafoil, pentafoil, and hexafoil) were consistently measured near zero with the OPD-Scan. Conclusion Both devices showed similar level of reproducibility; however, there was considerable difference in the wavefront reading between machines when measuring the same eye. Differences in the number of sample points, centration, and measurement algorithms between the two instruments may explain our results. PMID:17571088

Implementation and process analysis of pilot scale multi-phase anaerobic fermentation and digestion of faecal sludge in Ghana

PubMed Central

Shih, Justin; Fanyin-Martin, Ato; Taher, Edris; Chandran, Kartik

2017-01-01

Background.  In Ghana, faecal sludge (FS) from on-site sanitation facilities is often discharged untreated into the environment, leading to significant insults to environmental and human health. Anaerobic digestion offers an attractive pathway for FS treatment with the concomitant production of energy in the form of methane. Another innovative option includes separating digestion into acidogenesis (production of volatile fatty acids (VFA)) and methanogenesis (production of methane), which could ultimately facilitate the production of an array of biofuels and biochemicals from the VFA. This work describes the development, implementation and modeling based analysis of a novel multiphase anaerobic fermentation-digestion process aimed at FS treatment in Kumasi, Ghana.  Methods.  A pilot-scale anaerobic fermentation process was implemented at the Kumasi Metropolitan Assembly’s Oti Sanitary Landfill Site at Adanse Dompoase.  The process consisted of six 10 m reactors in series, which were inoculated with bovine rumen and fed with fecal sludge obtained from public toilets.  The performance of the fermentation process was characterized in terms of both aqueous and gaseous variables representing the conversion of influent organic carbon to VFA as well as CH 4.  Using the operating data, the first-ever process model for FS fermentation and digestion was developed and calibrated, based on the activated sludge model framework. Results and Conclusions.  This work represents one of the first systematic efforts at integrated FS characterization and process modeling to enable anaerobic fermentation and digestion of FS. It is shown that owing to pre-fermentation of FS in public septage holding tanks, one could employ significantly smaller digesters (lower capital costs) or increased loading capabilities for FS conversion to biogas or VFA. Further, using the first-ever calibrated process model for FS fermentation and digestion presented herein, we expect improved and more mechanistically informed development and application of different process designs and configurations for global FS management practice. PMID:29528044

Accurate T1 mapping of short T2 tissues using a three-dimensional ultrashort echo time cones actual flip angle imaging-variable repetition time (3D UTE-Cones AFI-VTR) method.

PubMed

Ma, Ya-Jun; Lu, Xing; Carl, Michael; Zhu, Yanchun; Szeverenyi, Nikolaus M; Bydder, Graeme M; Chang, Eric Y; Du, Jiang

2018-08-01

To develop an accurate T 1 measurement method for short T 2 tissues using a combination of a 3-dimensional ultrashort echo time cones actual flip angle imaging technique and a variable repetition time technique (3D UTE-Cones AFI-VTR) on a clinical 3T scanner. First, the longitudinal magnetization mapping function of the excitation pulse was obtained with the 3D UTE-Cones AFI method, which provided information about excitation efficiency and B 1 inhomogeneity. Then, the derived mapping function was substituted into the VTR fitting to generate accurate T 1 maps. Numerical simulation and phantom studies were carried out to compare the AFI-VTR method with a B 1 -uncorrected VTR method, a B 1 -uncorrected variable flip angle (VFA) method, and a B 1 -corrected VFA method. Finally, the 3D UTE-Cones AFI-VTR method was applied to bovine bone samples (N = 6) and healthy volunteers (N = 3) to quantify the T 1 of cortical bone. Numerical simulation and phantom studies showed that the 3D UTE-Cones AFI-VTR technique provides more accurate measurement of the T 1 of short T 2 tissues than the B 1 -uncorrected VTR and VFA methods or the B 1 -corrected VFA method. The proposed 3D UTE-Cones AFI-VTR method showed a mean T 1 of 240 ± 25 ms for bovine cortical bone and 218 ± 10 ms for the tibial midshaft of human volunteers, respectively, at 3 T. The 3D UTE-Cones AFI-VTR method can provide accurate T 1 measurements of short T 2 tissues such as cortical bone. Magn Reson Med 80:598-608, 2018. © 2018 International Society for Magnetic Resonance in Medicine. © 2018 International Society for Magnetic Resonance in Medicine.

Implementation and process analysis of pilot scale multi-phase anaerobic fermentation and digestion of faecal sludge in Ghana.

PubMed

Shih, Justin; Fanyin-Martin, Ato; Taher, Edris; Chandran, Kartik

2017-11-06

Background.  In Ghana, faecal sludge (FS) from on-site sanitation facilities is often discharged untreated into the environment, leading to significant insults to environmental and human health. Anaerobic digestion offers an attractive pathway for FS treatment with the concomitant production of energy in the form of methane. Another innovative option includes separating digestion into acidogenesis (production of volatile fatty acids (VFA)) and methanogenesis (production of methane), which could ultimately facilitate the production of an array of biofuels and biochemicals from the VFA. This work describes the development, implementation and modeling based analysis of a novel multiphase anaerobic fermentation-digestion process aimed at FS treatment in Kumasi, Ghana.  Methods.  A pilot-scale anaerobic fermentation process was implemented at the Kumasi Metropolitan Assembly's Oti Sanitary Landfill Site at Adanse Dompoase.  The process consisted of six 10 m reactors in series, which were inoculated with bovine rumen and fed with fecal sludge obtained from public toilets.  The performance of the fermentation process was characterized in terms of both aqueous and gaseous variables representing the conversion of influent organic carbon to VFA as well as CH 4 .  Using the operating data, the first-ever process model for FS fermentation and digestion was developed and calibrated, based on the activated sludge model framework. Results and Conclusions.  This work represents one of the first systematic efforts at integrated FS characterization and process modeling to enable anaerobic fermentation and digestion of FS. It is shown that owing to pre-fermentation of FS in public septage holding tanks, one could employ significantly smaller digesters (lower capital costs) or increased loading capabilities for FS conversion to biogas or VFA. Further, using the first-ever calibrated process model for FS fermentation and digestion presented herein, we expect improved and more mechanistically informed development and application of different process designs and configurations for global FS management practice.

Effect of transportation on fecal bacterial communities and fermentative activities in horses: impact of Saccharomyces cerevisiae CNCM I-1077 supplementation.

PubMed

Faubladier, C; Chaucheyras-Durand, F; da Veiga, L; Julliand, V

2013-04-01

This study evaluated the effect of transportation on fecal bacterial communities and activities in horses with or without supplementation of live yeast and attempted to link those effects with changes in blood stress markers. Four mature horses were assigned to a crossover design and fed a basal diet (60:40 forage to concentrate; 1.45% BW on a DM basis), with or without supplementation, of 2 × 10(10) cfu/d of Saccharomyces cerevisiae CNCM I-1077. After a 14-d adaptation to dietary treatments, the 5-d experiment started 1 d before transportation (d -1). At d 0, horses were simultaneously transported in a truck for 2 h. Feces were sampled 4 h after the morning meal of concentrate at d -1, 0 (immediately after transportation), and 3 for enumeration of the main functional bacterial groups and determination of fermentative variables. Within each dietary treatment, feces were pooled before DNA extraction and molecular analysis of the bacterial communities, using temporal temperature gradient electrophoreses (TTGE). Blood samples were collected at the same time for determination of white blood cells (WBC) counts and glucose and total protein concentrations. Regardless of dietary treatment, the neutrophil to lymphocyte ratio increased during transportation (P < 0.01), indicating that horses were stressed. In both treatments, TTGE profiles were clearly different before and 3 d after transportation, and the percentage of similarity between profiles at d -1 and 3 was greater in supplemented horses compared with the controls. From d 0 to 3, the molar percentage of propionate increased and total concentration of VFA and the acetate + butyrate to propionate ratio decreased, regardless of dietary treatment (P < 0.01, P = 0.02, and P < 0.01, respectively), whereas pH decreased only in control horses (P = 0.03). Regardless of day of sampling, fecal concentrations of lactate-utilizing bacteria and cellulolytic bacteria were greater in supplemented horses than in control horses (P = 0.04 and 0.08, respectively). Our results indicate that transportation for 2 h disturbed the fecal bacterial ecosystem in horses that could increase the risk of triggering microbial dysbiosis on a longer term in the equine large intestine. Supplementing Saccharomyces cerevisiae CNCM I-1077 could help reduce the negative impact of transportation on the fecal bacterial ecosystem.

Rumen fermentation and performance of Hanwoo steers fed total mixed ration with Korean rice wine residue.

PubMed

Jeong, Chang-Dae; Mamuad, Lovelia L; Ko, Jong Youl; Sung, Ha Guyn; Park, Keun Kyu; Lee, Yoo Kyung; Lee, Sang-Suk

2016-01-01

This study was conducted to evaluate the effects of adding Korean rice wine residue (RWR) in total mixed ration (TMR) on in vitro ruminal fermentation and growth performance of growing Hanwoo steers. For in vitro fermentation, the experimental treatments were Control (Con: 0 % RWR + TMR), Treatment 1 (T1: 10 % RWR + TMR), and Treatment 2 (T2: 15 % RWR + TMR). The rumen fluid was collected from three Hanwoo steers and mixed with buffer solution, after which buffered rumen fluid was transferred into serum bottles containing 2 g dry matter (DM) of TMR added with or without RWR. The samples were then incubated for 0 h, 12 h, 24 h, or 48 h at 39 °C and 100 rpm. For the in vivo experiment, 27 Hanwoo steers (6 months old) with an average weight of 196 ± 8.66 kg were subjected to a 24-week feeding trial. The animals were randomly selected and equally distributed into three groups. After which the body weight, feed intake and blood characteristics of each group were investigated. The pH of the treatments decreased significantly relative to the control during the 12 h of incubation. Total gas production and ammonia nitrogen (NH3-N) was not affected by RWR addition. The total volatile fatty acid (VFA) was lower after 24 h of incubation but at other incubation times, the concentration was not affected by treatments. Feed cost was 8 % and 15 % lower in T1 and T2 compared to control. Blood alcohol was not detected and a significant increase in total weight gain and average daily gain were observed in Hanwoo steers fed with RWR. Overall, the results of this study suggest that TMR amended with 15 % RWR can be used as an alternative feed resource for ruminants to reduce feed cost.

Nutritive value, fermentation characteristics, and in situ disappearance kinetics of ensiled warm-season legumes and bahiagrass.

PubMed

Foster, J L; Carter, J N; Sollenberger, L E; Blount, A R; Myer, R O; Maddox, M K; Phatak, S C; Adesogan, A T

2011-04-01

This study determined the nutritive value, ensiling characteristics, and in situ disappearance kinetics of bahiagrass (Paspalum notatum Flügge 'Tifton 9'), perennial peanut (Arachis glabrata Benth. 'Florigraze'), annual peanut [Arachis hypogaea (L.) 'FL MDR 98'], cowpea [Vigna unguiculata (L.) Walp. 'Iron clay'], and pigeonpea [Cajanus cajan (L.) Millsp. 'GA-2']. All forages were harvested at maturity stages that optimized dry matter (DM) yield and nutritive value. After harvest, forages were wilted to 45% DM, and 4 replicate bales of each legume and 8 bales of bahiagrass were wrapped in polyethylene and ensiled for 180 d. After each bale was opened, the forage was thoroughly mixed, and representative subsamples were taken for laboratory analysis and in situ incubation. Wilting and ensiling decreased the rumen-undegradable protein, water-soluble carbohydrate, crude protein (CP), and in vitro true digestibility (IVTD) of bahiagrass, perennial peanut, and cowpea, and increased their neutral detergent fiber (NDF) concentrations. Among haylages, CP concentration was greatest for annual peanut, followed by perennial peanut and cowpea, and least for bahiagrass. In contrast, NDF concentration was greater in bahiagrass than in legumes. Pigeonpea had the greatest NDF concentration among legumes and lowest IVTD of all haylages. All haylages were aerobically stable for at least 84 h, but pH was lower in perennial peanut and cowpea than in pigeonpea. Ammonia-N concentrations tended to be greater in legume haylages than in bahiagrass haylage. Butyrate concentration was greater in annual and perennial peanut than in bahiagrass. Total VFA concentration was greater in annual and perennial peanut and cowpea haylages than in bahiagrass haylage. Undegradable DM fractions were greater and extent of DM degradation was lower in bahiagrass and pigeonpea than in other haylages but lag time and degradation rates did not differ. Annual and perennial peanut and cowpea haylages were as aerobically stable and had greater CP, IVTD, and extent of degradation than did bahiagrass haylage; therefore, they are promising forages for dairy cow diets in the southeastern United States. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Mixed culture polyhydroxyalkanoates production from sugar molasses: the use of a 2-stage CSTR system for culture selection.

PubMed

Albuquerque, M G E; Concas, S; Bengtsson, S; Reis, M A M

2010-09-01

Polyhydroxyalkanoates (PHAs) are promising biodegradable polymers. The use of mixed microbial cultures (MMC) and low cost feedstocks have a positive impact on the cost-effectiveness of the process. It has typically been carried out in Sequencing Batch Reactors (SBR). In this study, a 2-stage CSTR system (under Feast and Famine conditions) was used to effectively select for PHA-storing organisms using fermented molasses as feedstock. The effect of influent substrate concentration (60-120 Cmmol VFA/L) and HRT ratio between the reactors (0.2-0.5h/h) on the system's selection efficiency was assessed. It was shown that Feast reactor residual substrate concentration impacted on the selective pressure for PHA storage (due to substrate-dependent kinetic limitation). Moreover, a residual substrate concentration coming from the Feast to the Famine reactor did not jeopardize the physiological adaptation required for enhanced PHA storage. The culture reached a maximum PHA content of 61%. This success opens new perspectives to the use of wastewater treatment infrastructure for PHA production, thus valorizing either excess sludge or wastewaters. Copyright 2010 Elsevier Ltd. All rights reserved.

Improved production of propionic acid driven by hydrolyzed liquid containing high concentration of l-lactic acid from co-fermentation of food waste and sludge.

PubMed

Li, Xiang; Zhang, Wenjuan; Ma, Li; Lai, Sizhou; Zhao, Shu; Chen, Yinguang; Liu, Yanan

2016-11-01

This study investigated the feasibility of improved production propionic acid-enriched volatile fatty acid (VFA) from high concentration (Cs) of food waste and waste activated sludge (WAS) via lactic acid pathway by using of Propionibacterium acidipropionici. It was observed that production of l-lactate overwhelmed to d-lactate at first stage, which improved from 3.21 to 35.45gCOD/L with increase of substrate Cs. However, kinetic model analysis indicated that P. acidipropionici growth rate μmax was decreased with increase of l-lactate concentration, which explained second stage free cell fermentation of propionic acid was inhibited when fed by first stage liquid from R-40, R-55 and R-70. Then, the fibrous bed bioreactor was employed to eliminate the feed inhibition. The maximal percentage of propionic acid (68.3%) and production (16.31gCOD/L) was obtained by feeding liquid of R-55, which was improved by 3.33 folds compared to the free cell fermentation. Copyright © 2016. Published by Elsevier Ltd.

Milk production is unaffected by replacing barley or sodium hydroxide wheat with maize cob silage in rations for dairy cows.

PubMed

Hymøller, L; Hellwing, A L F; Lund, P; Weisbjerg, M R

2014-05-01

Starch is an important energy-providing nutrient for dairy cows that is most commonly provided from cereal grains. However, ruminal fermentation of large amounts of easily degradable starch leads to excessive production and accumulation of volatile fatty acids (VFA). VFA not only play a vital role in the energy metabolism of dairy cows but are also the main cause of ruminal acidosis and depressed feed intake. The aim of the present study was to compare maize cob silage (MCS) as an energy supplement in rations for dairy cows with highly rumen-digestible rolled barley and with sodium hydroxide wheat (SHW), which has a higher proportion of by-pass starch than barley. Two studies were carried out: (1) a production study on 45 Danish Holstein cows and (2) an intensive study to determine digestibilities, rumen fermentation patterns and methane emission using three rumen-cannulated Danish Holstein cows. Both studies were organised as a 3×3 Latin square with three experimental periods and three different mixed rations. The rations consisted of grass-clover silage and maize silage (~60% of dry matter (DM)), rapeseed cake, soybean meal, sugar beet pulp and one of three different cereals as a major energy supplement: MCS, SHW or rolled barley (~25% of DM). When MCS replaced barley or SHW as an energy supplement in the mixed rations, it resulted in a lower dry matter intake; however, the apparent total tract digestibilities of DM, organic matter, NDF, starch and protein were not different between treatments. The energy-corrected milk yield was unaffected by treatment. The fat content of the milk on the MCS ration was not different from the SHW ration, whereas it was higher on the barley ration. The protein content of the milk decreased when MCS was used in the ration compared with barley and SHW. From ruminal VFA patterns and pH measures, it appeared that MCS possessed roughage qualities with respect to rumen environment, while at the same time being sufficiently energy rich to replace barley and SHW as a major energy supplement for milk production. The environmental impact, expressed as methane emissions, was not different when comparing MCS, SHW and barley.

Manipulation of rumen ecology by dietary lemongrass (Cymbopogon citratus Stapf.) powder supplementation.

PubMed

Wanapat, M; Cherdthong, A; Pakdee, P; Wanapat, S

2008-12-01

This experiment was conducted to investigate the effect of lemongrass [Cymbopogon citratus (DC.) Stapf.] powder (LGP) on rumen ecology, rumen microorganisms, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman native) beef cattle were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were LGP supplementation at 0, 100, 200, and 300 g/d with urea-treated rice straw (5%) fed to allow ad libitum intake. Digestibilities of DM, ether extract, and NDF were significantly different among treatments and were greatest at 100 g/d of supplementation. However, digestibility of CP was decreased with LGP supplementation (P < 0.05), whereas ruminal NH(3)-N and plasma urea N were decreased with incremental additions of LGP (P < 0.05). Ruminal VFA concentrations were similar among supplementation concentrations (P > 0.05). Total viable bacteria, amylolytic bacteria, and cellulolytic bacteria were significantly different among treatments and were greatest at 100 g/d of supplementation (4.7 x 10(9), 1.7 x 10(7), and 2.0 x 10(9) cfu/mL, respectively). Protozoal populations were significantly decreased by LGP supplementation. In addition, efficiency of rumen microbial N synthesis based on OM truly digested in the rumen was enriched by LGP supplementation, especially at 100 g/d (34.2 g of N/kg of OM truly digested in the rumen). Based on this study, it could be concluded that supplementation of LGP at 100 g/d improved digestibilities of nutrients, rumen microbial population, and microbial protein synthesis efficiency, thus improving rumen ecology in beef cattle.

Dietary Fat Content and Fiber Type Modulate Hind Gut Microbial Community and Metabolic Markers in the Pig

PubMed Central

Yan, Hui; Potu, Ramesh; Lu, Hang; Vezzoni de Almeida, Vivian; Stewart, Terry; Ragland, Darryl; Armstrong, Arthur; Adeola, Olayiwola; Nakatsu, Cindy H.; Ajuwon, Kolapo M.

2013-01-01

Obesity leads to changes in the gut microbial community which contribute to the metabolic dysregulation in obesity. Dietary fat and fiber affect the caloric density of foods. The impact of dietary fat content and fiber type on the microbial community in the hind gut is unknown. Effect of dietary fat level and fiber type on hindgut microbiota and volatile fatty acid (VFA) profiles was investigated. Expression of metabolic marker genes in the gut, adipose tissue and liver was determined. A 2×2 experiment was conducted in pigs fed at two dietary fat levels (5% or 17.5% swine grease) and two fiber types (4% inulin, fermentable fructo-oligosaccharide or 4% solka floc, non-fermentable cellulose). High fat diets (HFD) resulted in a higher (P<0.05) total body weight gain, feed efficiency and back fat accumulation than the low fat diet. Feeding of inulin, but not solka floc, attenuated (P<0.05) the HFD-induced higher body weight gain and fat mass accumulation. Inulin feeding tended to lead to higher total VFA production in the cecum and resulted in a higher (P<0.05) expression of acyl coA oxidase (ACO), a marker of peroxisomal β-oxidation. Inulin feeding also resulted in lower expression of sterol regulatory element binding protein 1c (SREBP-1c), a marker of lipid anabolism. Bacteria community structure characterized by DGGE analysis of PCR amplified 16S rRNA gene fragments showed that inulin feeding resulted in greater bacterial population richness than solka floc feeding. Cluster analysis of pairwise Dice similarity comparisons of the DGGE profiles showed grouping by fiber type but not the level of dietary fat. Canonical correspondence analysis (CCA) of PCR- DGGE profiles showed that inulin feeding negatively correlated with back fat thickness. This study suggests a strong interplay between dietary fat level and fiber type in determining susceptibility to obesity. PMID:23573202

Effect of 3-nitrooxypropanol on methane and hydrogen emissions, methane isotopic signature, and ruminal fermentation in dairy cows.

PubMed

Lopes, J C; de Matos, L F; Harper, M T; Giallongo, F; Oh, J; Gruen, D; Ono, S; Kindermann, M; Duval, S; Hristov, A N

2016-07-01

The objective of this crossover experiment was to investigate the effect of a methane inhibitor, 3-nitrooxypropanol (3NOP), on enteric methane emission, methane isotopic composition, and rumen fermentation and microbial profile in lactating dairy cows. The experiment involved 6 ruminally cannulated late-lactation Holstein cows assigned to 2 treatments: control and 3NOP (60 mg/kg of feed dry matter). Compared with the control, 3NOP decreased methane emission by 31% and increased hydrogen emission from undetectable to 1.33 g/d. Methane emissions per kilogram of dry matter intake and milk yield were also decreased 34% by 3NOP. Milk production and composition were not affected by 3NOP, except milk fat concentration was increased compared with the control. Concentrations of total VFA and propionate in ruminal fluid were not affected by treatment, but acetate concentration tended to be lower and acetate-to-propionate ratio was lower for 3NOP compared with the control. The 3NOP decreased the molar proportion of acetate and increase those of propionate, butyrate, valerate, and isovalerate. Deuterium-to-hydrogen ratios of methane and the abundance of (13)CH3D were similar between treatments. Compared with the control, minor (4‰) depletion in the (13)C/(12)C ratio was observed for 3NOP. Genus composition of methanogenic archaea (Methanobrevibacter, Methanosphaera, and Methanomicrobium) was not affected by 3NOP, but the proportion of methanogens in the total cell counts tended to be decreased by 3NOP. Prevotella spp., the predominant bacterial genus in ruminal contents in this experiment, was also not affected by 3NOP. Compared with the control, Ruminococcus and Clostridium spp. were decreased and Butyrivibrio spp. was increased by 3NOP. This experiment demonstrated that a substantial inhibition of enteric methane emission by 3NOP in dairy cows was accompanied with increased hydrogen emission and decreased acetate-to-propionate ratio; however, neither an effect on rumen archaeal community composition nor a significant change in the isotope composition of methane was observed. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Dark fermentation process as pretreatment for a sustainable denaturation of asbestos containing wastes.

PubMed

Spasiano, Danilo

2018-05-05

A cement asbestos compound (CAC) sample was detoxified by a treatment train based on a dark fermentation (DF) process followed by a hydrothermal phase, which led to the complete degradation of the chrysotile fibers. During the biological pretreatment, the glucose was converted in biogas rich in H 2 and volatile fatty acids (VFA). The latter caused the dissolution of all the Ca-based compounds and the solubilisation of 50% brucite-like layers of chrysotile fibers contained in the CAC suspended in the bioreactor (5 g/L). XRD analysis of the solids contained in the effluents of the DF process highlighted the disappearance of the chrysotile fiber peaks. However, a complete destruction of all the asbestos fibers is hard to prove and a hydrothermal treatment was carried out to dissolve the "brucite" layers still present in solution. Due to the presence of the VFA produced during the DF, a complete destruction of chrysotile fibers was achieved by a 24 h hydrothermal process performed with a [H 2 SO 4 ]/[CAC] ratio 50% lower than that adopted in a previous finding. Consequently, the DF pre-treatment can contribute to lower the H 2 SO 4 and the energy consumption of a CAC hydrothermal treatment, due to the production of VFA and H 2 . Copyright © 2018 Elsevier B.V. All rights reserved.

Plasma Free Amino Acid Profiles Predict Four-Year Risk of Developing Diabetes, Metabolic Syndrome, Dyslipidemia, and Hypertension in Japanese Population

PubMed Central

Yamakado, Minoru; Nagao, Kenji; Imaizumi, Akira; Tani, Mizuki; Toda, Akiko; Tanaka, Takayuki; Jinzu, Hiroko; Miyano, Hiroshi; Yamamoto, Hiroshi; Daimon, Takashi; Horimoto, Katsuhisa; Ishizaka, Yuko

2015-01-01

Plasma free amino acid (PFAA) profile is highlighted in its association with visceral obesity and hyperinsulinemia, and future diabetes. Indeed PFAA profiling potentially can evaluate individuals’ future risks of developing lifestyle-related diseases, in addition to diabetes. However, few studies have been performed especially in Asian populations, about the optimal combination of PFAAs for evaluating health risks. We quantified PFAA levels in 3,701 Japanese subjects, and determined visceral fat area (VFA) and two-hour post-challenge insulin (Ins120 min) values in 865 and 1,160 subjects, respectively. Then, models between PFAA levels and the VFA or Ins120 min values were constructed by multiple linear regression analysis with variable selection. Finally, a cohort study of 2,984 subjects to examine capabilities of the obtained models for predicting four-year risk of developing new-onset lifestyle-related diseases was conducted. The correlation coefficients of the obtained PFAA models against VFA or Ins120 min were higher than single PFAA level. Our models work well for future risk prediction. Even after adjusting for commonly accepted multiple risk factors, these models can predict future development of diabetes, metabolic syndrome, and dyslipidemia. PFAA profiles confer independent and differing contributions to increasing the lifestyle-related disease risks in addition to the currently known factors in a general Japanese population. PMID:26156880

Effects of fat and/or methionine hydroxy analog added to a molasses-urea-based supplement on ruminal and postruminal digestion and duodenal flow of nutrients in beef steers consuming low-quality lovegrass hay.

PubMed

Lopez, R; Pulsipher, G D; Guerra-Liera, J E; Soto-Navarro, S A; Balstad, L A; Petersen, M K; Dhuyvetter, D V; Brown, M S; Krehbiel, C R

2016-06-01

Five crossbred beef steers (initial BW = 338.6 ± 7.8 kg) fitted with ruminal and duodenal cannulas were used in a 5 × 5 Latin square design experiment to evaluate the effects of methionine hydroxy analog (MHA) and/or yellow grease (fat) added to a molasses-urea-based supplement on intake and characteristics of digestion. Steers were fed low-quality hay (long-stem lovegrass : 3.3% CP, 76.8% NDF; DM basis) ad libitum and supplemented with 0.91 kg/d (as fed) of 1 of 4 supplements in a 2 × 2 + 1 factorial arrangement of treatments. Supplemental treatments were 1) control (no supplement, NC); 2) molasses-urea liquid supplement (U); 3) U containing (as-fed basis) 1.65% MHA (UM); 4) U containing (as-fed basis) 12% fat (UF); and 5) U containing (as-fed basis) 1.65% MHA and 12% fat (UMF). Total and forage OM intake (kg/d and as % of BW) increased ( < 0.01) with molasses-urea, decreased ( ≤ 0.04) with MHA, and were not affected ( = 0.61) with fat supplementation. Total tract NDF digestibility increased ( = 0.01) with molasses-urea supplementation, and was less ( = 0.01) for fat than for nonfat supplementation. Total and microbial N flowing to the duodenum increased ( = 0.01) with molasses-urea supplementation. Although, total N flowing to duodenum was not affected ( = 0.27), microbial N decreased ( = 0.01), and nonammonia nonmicrobial N (NANMN) increased ( = 0.01) with fat supplementation. Extent of in situ OM and NDF digestibility at 96 h increased ( = 0.01) with molasses-urea supplementation, but were not affected ( ≥ 0.14) by either MHA or fat supplementation. Duodenal flow of total AA, essential AA, and nonessential AA increased ( ≤ 0.02) with molasses-urea supplementation. Total and nonessential serum AA concentration decreased ( < 0.01) with molasses-urea supplementation. Total ruminal VFA concentration increased ( = 0.01) with molasses-urea supplementation, and was not affected ( ≥ 0.14) by MHA or fat supplementation. Fat can be used in molasses-urea liquid supplements for cattle consuming low-quality forage to increase energy intake without negatively affecting forage intake or characteristics of digestion. However, adding MHA did not further improve the response to urea supplementation of cattle consuming low-quality forage. Conversely, the inclusion of MHA on urea supplement decreased forage intake.

Enhancement options for the utilisation of nitrogen rich animal by-products in anaerobic digestion.

PubMed

Resch, Christoph; Wörl, Alexander; Waltenberger, Reinhold; Braun, Rudolf; Kirchmayr, Roland

2011-02-01

This study focuses on the enhancement of an Austrian anaerobic digestion plant at a slaughterhouse site which exclusively uses animal by-products as substrate. High ammonia concentrations from protein degradation cause severe inhibitions of anaerobic microorganisms. For improving the current situation the COD:TKN ratio is widened by (a) ammonia stripping directly out of the process and (b) addition of a C source to the substrate. Different OLR and HRT were tested in continuous experiments to simulate new operating conditions. The results show that the addition of carbon cannot improve fermentation capacity. The reduction of ammonia boosts the degradation: After reduction of TKN from 7.5 to 4.0 g kg(-1) the initially high VFA concentration decreased and the COD degradation was improved by 55.5%. Hence, the implementation of the new N reduction process facilitates either the increase of the OLR by 61% or the reduction of the HRT by 25%. Copyright © 2010 Elsevier Ltd. All rights reserved.

Degradation of oxytetracycline and its impacts on biogas-producing microbial community structure.

PubMed

Coban, Halil; Ertekin, Emine; Ince, Orhan; Turker, Gokhan; Akyol, Çağrı; Ince, Bahar

2016-07-01

The effect of veterinary antibiotics in anaerobic digesters is a concern where methane production efficiency is highly dependent on microbial community structure. In this study, both anaerobic degradation of a common veterinary antibiotic, oxytetracycline (OTC), and its effects on an anaerobic digester microbial community were investigated. Qualitative and quantitative molecular tools were used to monitor changes in microbial community structure during a 60-day batch incubation period of cow manure with the addition of different concentrations of the antibiotic. Molecular data were interpreted by a further redundancy analysis as a multivariate statistics approach. At the end of the experiment, approximately 48, 33, and 17 % of the initially added 50, 100, and 200 mg l(-1) of OTC was still present in the serum bottles which reduced the biogas production via accumulation of some of the volatile fatty acids (VFAs). Biogas production was highly correlated with Methanobacteriales and Methanosarcinales gene copy numbers, and those parameters were negatively affected with oxytetracycline and VFA concentrations.

Microbial characterization and degradation of linear alkylbenzene sulfonate in an anaerobic reactor treating wastewater containing soap powder.

PubMed

Carosia, Mariana Fronja; Okada, Dagoberto Yukio; Sakamoto, Isabel Kimiko; Silva, Edson Luiz; Varesche, Maria Bernadete Amâncio

2014-09-01

The aim of this study was to evaluate the removal of linear alkylbenzene sulfonate (LAS) in an anaerobic fluidized bed reactor (AFBR) treating wastewater containing soap powder as LAS source. At Stage I, the AFBR was fed with a synthetic substrate containing yeast extract and ethanol as carbon sources, and without LAS; at Stage II, soap powder was added to this synthetic substrate obtaining an LAS concentration of 14 ± 3 mg L(-1). The compounds of soap powder probably inhibited some groups of microorganisms, increasing the concentration of volatile fatty acids (VFA) from 91 to 143 mg HAc L(-1). Consequently, the LAS removal rate was 48 ± 10% after the 156 days of operation. By sequencing, 16S rRNA clones belonging to the phyla Proteobacteria and Synergistetes were identified in the samples taken at the end of the experiment, with a remarkable presence of Dechloromonas sp. and Geobacter sp. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of concentrate level on feeding behavior and rumen and blood parameters in dairy goats: relationships between behavioral and physiological parameters and effect of between-animal variability.

PubMed

Giger-Reverdin, S; Rigalma, K; Desnoyers, M; Sauvant, D; Duvaux-Ponter, C

2014-07-01

This work aimed first to compare 2 diets differing in their percentage of concentrate [low (LO): 30% concentrate vs. High (HI): 60% concentrate] by measuring simultaneously feeding behavior, rumen parameters, blood and plasma parameters, and milk yield and composition in 8 mid-lactation goats. The second aim was to study the interrelationships between these variables and to analyze the between-animal variability to better understand the between-animal differences in acidosis susceptibility. All of the animals received the 2 diets ad libitum as total mixed ration according to a crossover design of two 4-wk periods. Mean daily DMI was similar between the 2 diets but the variability was higher for the HI than for the LO diet. Goats produced more milk when fed the HI diet compared with the LO diet but with a lower fat:protein ratio (0.81 vs. 0.99). They ate more rapidly the HI than the LO diet but stopped eating sooner after the afternoon feed allowance, and spent less time chewing. The increase in concentrate percentage modified rumen parameters: the pH and acetate:propionate ratio decreased and total VFA, ammonia, and soluble carbohydrate concentrations increased. Hematocrit, plasma NEFA, and blood K and Ca concentrations decreased but glycemia and uremia increased. Other parameters were not modified: milk fat content, blood pH, and bicarbonate and Na concentrations. A large between-animal variability was detected for all the measured parameters, especially for feeding behavior, with important consequences on rumen and blood parameters. This work confirmed the effects of a high percentage of concentrate on feeding behavior, rumen and blood parameters, and milk production, and some known relationships such as the positive link between rumen pH and chewing index. It also pointed out other relationships between parameters seldom measured at the same time, such as rumen redox potential or blood pH and chewing index, or the negative link between blood and rumen pH. When the animals spent a lot of time chewing, they probably produced a lot of saliva that buffered the rumen pH and prevented them from suffering from subacute ruminal acidosis. However, they used part of their blood bicarbonates reserve, which might have induced metabolic acidosis, as rumen and blood pH were inversely related. This could explain why some animals suffer from acidosis and others do not in a herd receiving the same diet, and why some animals seem to suffer more from subacute ruminal acidosis and others from metabolic acidosis. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

An analysis of the uncertainty and bias in DCE-MRI measurements using the spoiled gradient-recalled echo pulse sequence.

PubMed

Subashi, Ergys; Choudhury, Kingshuk R; Johnson, G Allan

2014-03-01

The pharmacokinetic parameters derived from dynamic contrast-enhanced (DCE) MRI have been used in more than 100 phase I trials and investigator led studies. A comparison of the absolute values of these quantities requires an estimation of their respective probability distribution function (PDF). The statistical variation of the DCE-MRI measurement is analyzed by considering the fundamental sources of error in the MR signal intensity acquired with the spoiled gradient-echo (SPGR) pulse sequence. The variance in the SPGR signal intensity arises from quadrature detection and excitation flip angle inconsistency. The noise power was measured in 11 phantoms of contrast agent concentration in the range [0-1] mM (in steps of 0.1 mM) and in onein vivo acquisition of a tumor-bearing mouse. The distribution of the flip angle was determined in a uniform 10 mM CuSO4 phantom using the spin echo double angle method. The PDF of a wide range of T1 values measured with the varying flip angle (VFA) technique was estimated through numerical simulations of the SPGR equation. The resultant uncertainty in contrast agent concentration was incorporated in the most common model of tracer exchange kinetics and the PDF of the derived pharmacokinetic parameters was studied numerically. The VFA method is an unbiased technique for measuringT1 only in the absence of bias in excitation flip angle. The time-dependent concentration of the contrast agent measured in vivo is within the theoretically predicted uncertainty. The uncertainty in measuring K(trans) with SPGR pulse sequences is of the same order, but always higher than, the uncertainty in measuring the pre-injection longitudinal relaxation time (T10). The lowest achievable bias/uncertainty in estimating this parameter is approximately 20%-70% higher than the bias/uncertainty in the measurement of the pre-injection T1 map. The fractional volume parameters derived from the extended Tofts model were found to be extremely sensitive to the variance in signal intensity. The SNR of the pre-injection T1 map indicates the limiting precision with which K(trans) can be calculated. Current small-animal imaging systems and pulse sequences robust to motion artifacts have the capacity for reproducible quantitative acquisitions with DCE-MRI. In these circumstances, it is feasible to achieve a level of precision limited only by physiologic variability.

The influence of oscillating dietary protein concentrations on finishing cattle. I. Feedlot performance and odorous compound production.

PubMed

Archibeque, S L; Miller, D N; Freetly, H C; Berry, E D; Ferrell, C L

2007-06-01

We hypothesized that oscillation of the dietary CP concentration, which may improve N retention of finishing beef steers, would reduce production of manure odor compounds and total N inputs while yielding comparable performance. Charolais-sired steers (n = 144; 303 +/- 5 kg of initial BW) were used in a completely randomized block design (6 pens/treatment). The steers were fed to 567 kg of BW on the following finishing diets, which were based on dry-rolled corn: 1) low (9.1% CP), 2) medium (11.8% CP), 3) high (14.9% CP), or 4) low and high oscillated on a 48-h interval for each feed (oscillating). Steers fed low tended (P = 0.08) to have less DMI (7.80 kg/d) than steers fed medium (8.60 kg/d) or oscillating (8.67 kg/d), but not less than steers fed high (8.12 kg/d). Daily N intake was greatest (P < 0.01) for steers fed high (189 g), intermediate for medium (160 g) and oscillating (164 g), and least for low (113 g). The ADG was lower (P < 0.01) for steers fed low (1.03 kg) than for those fed medium (1.45 kg), high (1.45 kg), or oscillating (1.43 kg). Similarly, steers fed low had a lower adjusted fat thickness (P < 0.01) and yield grade (P = 0.05) and tended (P = 0.10) to have less marbling than steers fed the other 3 diets. In slurries with feces, urine, soil, and water, incubated for 35 d, nonsoluble CP was similar among slurries from steers fed medium, high, or oscillating, but was less (P < 0.01) in slurries from steers fed low. However, throughout the incubation period, slurries from steers fed high or oscillating had greater (P < 0.01) concentrations of total aromatics and ammonia than those from steers fed low or medium. Also, the slurries from steers fed oscillating had greater (P < 0.01) concentrations of branched-chain VFA than manure slurries from steers fed any of the other diets. These data indicate that although there is no apparent alteration in the performance of finishing steers fed diets with oscillation of the dietary protein, there may be undesirable increases in the production of compounds associated with malodor.

Copper stressed anaerobic fermentation: biogas properties, process stability, biodegradation and enzyme responses.

PubMed

Hao, He; Tian, Yonglan; Zhang, Huayong; Chai, Yang

2017-12-01

The effect of copper (added as CuCl 2 ) on the anaerobic co-digestion of Phragmites straw and cow dung was studied in pilot experiments by investigating the biogas properties, process stability, substrate degradation and enzyme activities at different stages of mesophilic fermentation. The results showed that 30 and 100 mg/L Cu 2+ addition increased the cumulative biogas yields by up to 43.62 and 20.77% respectively, and brought forward the daily biogas yield peak, while 500 mg/L Cu 2+ addition inhibited biogas production. Meanwhile, the CH 4 content in the 30 and 100 mg/L Cu 2+ -added groups was higher than that in the control group. Higher pH values (close to pH 7) and lower oxidation-reduction potential (ORP) values in the Cu 2+ -added groups after the 8th day indicated better process stability compared to the control group. In the presence of Cu 2+ , the degradation of volatile fatty acids (VFAs) and other organic molecules (represented by chemical oxygen demand, COD) generated from hydrolysis was enhanced, and the ammonia nitrogen (NH 4 + -N) concentrations were more stable than in the control group. The contents of lignin and hemicellulose in the substrate declined in the Cu 2+ -added groups while the cellulose contents did not. Neither the cellulase nor the coenzyme F 420 activities could determine the biogas producing efficiency. Taking the whole fermentation process into account, the promoting effect of Cu 2+ addition on biogas yields was mainly attributable to better process stability, the enhanced degradation of lignin and hemicellulose, the transformation of intermediates into VFA, and the generation of CH 4 from VFA.

Effect of fiber-based creep feed on intake, digestion, ruminal fermentation, and microbial efficiency in nursing calves.

PubMed

Soto-Navarro, S A; Knight, M H; Lardy, G P; Bauer, M L; Caton, J S

2004-12-01

Six Angus crossbred cow-calf pairs (653 +/- 35 kg and 157 +/- 10 kg initial BW for cows and calves, respectively) were used to evaluate the influence of a fiber-based creep feed on intake, ruminal fermentation, digestion characteristics, and microbial efficiency in nursing beef calves. Cow-calf pairs were stratified by calf age and assigned randomly to one of two treatments: control (no supplement) or supplemented. Supplemented calves received 0.9 kg of a 49% soy hulls, 44% wheat middlings, 6% molasses, and 1% limestone supplement (DM basis) daily. All calves were cannulated in the rumen and duodenum and given ad libitum access to chopped brome hay (Bromus inermus L; 7.43% CP, 40.96% ADF, and 63.99% NDF; DM basis). Supplementation was initiated on May 1 (88 +/- 10.3 d calf age). Three sampling periods were conducted throughout the study (June 14 to 25, July 5 to 16, and August 9 to 20). Supplement and forage were offered at 0800 daily. Total, hay, and milk OM intakes of nursing calves were not affected by supplementation (2,014 vs. 2,328 +/- 288.8, 1,486 vs. 1,029 +/- 3,06.9, and 528 vs. 575 +/- 87.0 g/d, respectively). Milk OM intake was less (P < 0.09) in August than in June and July (635, 691, and 345 +/- 110.6 g/d for June, July, and August, respectively). A supplementation x month interaction occurred (P < 0.10) for total-tract OM digestion. Supplementation did not affect (P > 0.40) total-tract OM digestibility during June and August; however, during July, total-tract OM digestibility was lower (P = 0.03) for the control calves. Ruminal ammonia concentration, total VFA, and butyrate molar proportion increased (P < 0.05), whereas acetate proportion decreased (P = 0.01) in supplemented calves. Microbial efficiency was not influenced by supplementation (11.8 vs. 12.0 g/kg of OM truly fermented for control and supplemented calves, respectively). These data indicate that fiber-based supplements can be used as creep feed without negative effects on OM intake, total-tract OM digestibility, and ruminal fermentation characteristics in nursing beef calves.

Effect of ammoniacal nitrogen on one-stage and two-stage anaerobic digestion of food waste.

PubMed

Ariunbaatar, Javkhlan; Scotto Di Perta, Ester; Panico, Antonio; Frunzo, Luigi; Esposito, Giovanni; Lens, Piet N L; Pirozzi, Francesco

2015-04-01

This research compares the operation of one-stage and two-stage anaerobic continuously stirred tank reactor (CSTR) systems fed semi-continuously with food waste. The main purpose was to investigate the effects of ammoniacal nitrogen on the anaerobic digestion process. The two-stage system gave more reliable operation compared to one-stage due to: (i) a better pH self-adjusting capacity; (ii) a higher resistance to organic loading shocks; and (iii) a higher conversion rate of organic substrate to biomethane. Also a small amount of biohydrogen was detected from the first stage of the two-stage reactor making this system attractive for biohythane production. As the digestate contains ammoniacal nitrogen, re-circulating it provided the necessary alkalinity in the systems, thus preventing an eventual failure by volatile fatty acids (VFA) accumulation. However, re-circulation also resulted in an ammonium accumulation, yielding a lower biomethane production. Based on the batch experimental results the 50% inhibitory concentration of total ammoniacal nitrogen on the methanogenic activities was calculated as 3.8 g/L, corresponding to 146 mg/L free ammonia for the inoculum used for this research. The two-stage system was affected by the inhibition more than the one-stage system, as it requires less alkalinity and the physically separated methanogens are more sensitive to inhibitory factors, such as ammonium and propionic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical composition, silage fermentation characteristics, and in vitro ruminal fermentation parameters of potato-wheat straw silage treated with molasses and lactic acid bacteria and corn silage.

PubMed

Babaeinasab, Y; Rouzbehan, Y; Fazaeli, H; Rezaei, J

2015-09-01

The aim of this study was to determine the effect of molasses and lactic acid bacteria (LAB) on the chemical composition, silage fermentation characteristics, and in vitro ruminal fermentation parameters of an ensiled potato-wheat straw mixture in a completely randomized design with 4 replicates. Wheat straw was harvested at full maturity and potato tuber when the leaves turned yellowish. The potato-wheat straw (57:43 ratio, DM basis) mixture was treated with molasses, LAB, or a combination. Lalsil Fresh LB (Lallemand, France; containing NCIMB 40788) or Lalsil MS01 (Lallemand, France; containing MA18/5U and MA126/4U) were each applied at a rate of 3 × 10 cfu/g of fresh material. Treatments were mixed potato-wheat straw silage (PWSS) without additive, PWSS inoculated with Lalsil Fresh LB, PWSS inoculated with Lalsil MS01, PWSS + 5% molasses, PWSS inoculated with Lalsil Fresh LB + 5% molasses, PWSS inoculated with Lalsil MS01 + 5% molasses, and corn silage (CS). The compaction densities of PWSS treatments and CS were approximately 850 and 980 kg wet matter/m, respectively. After anaerobic storage for 90 d, chemical composition, silage fermentation characteristics, in vitro gas production (GP), estimated OM disappearance (OMD), ammonia-N, VFA, microbial CP (MCP) production, and cellulolytic bacteria count were determined. Compared to CS, PWSS had greater ( < 0.001) values of DM, ADL, water-soluble carbohydrates, pH, and ammonia-N but lower ( < 0.05) values of CP, ash free-NDF (NDFom), ash, nitrate, and lactic, acetic, propionic, and butyric acids concentrations. When PWSS was treated with molasses, LAB, or both, the contents of CP and lactic and acetic acids increased, whereas NDFom, ammonia-N, and butyric acid decreased ( < 0.05). Based on in vitro ruminal experiments, PWSS had greater ( < 0.05) values of GP, OMD, and MCP but lower ( < 0.05) VFA and acetic acid compared to CS. With adding molasses alone or in combination with LAB inoculants to PWSS, the values of GP, OMD, MCP, cellulolytic bacteria population, VFA, and propionic acid increased ( < 0.05), whereas the acetic acid to propionic acid ratio decreased ( < 0.05). Overall, ensiling potato with wheat straw at a 57:43 ratio DM basis was possible; nevertheless, the fermentation quality of PWSS was lesser than that of CS. However, addition of molasses and molasses + LAB improved fermentation quality of PWSS.

Application of Methanobrevibacter acididurans in anaerobic digestion.

PubMed

Savant, D V; Ranade, D R

2004-01-01

To operate anaerobic digesters successfully under acidic conditions, hydrogen utilizing methanogens which can grow efficiently at low pH and tolerate high volatile fatty acids (VFA) are desirable. An acid tolerant hydrogenotrophic methanogen viz. Methanobrevibacter acididurans isolated from slurry of an anaerobic digester running on alcohol distillery wastewater has been described earlier by this lab. This organism could grow optimally at pH 6.0. In the experiments reported herein, M. acididurans showed better methanogenesis under acidic conditions with high VFA, particularly acetate, than Methanobacterium bryantii, a common hydrogenotrophic inhabitant of anaerobic digesters. Addition of M. acididurans culture to digesting slurry of acidogenic as well as methanogenic digesters running on distillery wastewater showed increase in methane production and decrease in accumulation of volatile fatty acids. The results proved the feasibility of application of M. acididurans in anaerobic digesters.

Significance of measuring oxidative stress in lifestyle-related diseases from the viewpoint of correlation between d-ROMs and BAP in Japanese subjects.

PubMed

Fukui, Toshiki; Yamauchi, Kazuhiro; Maruyama, Mie; Yasuda, Tadashi; Kohno, Masakazu; Abe, Youichi

2011-09-01

In recent years, oxidative stress has been postulated to be an important factor in the pathogenesis and development of lifestyle-related diseases. In this study, we investigated the association between the derivatives of reactive oxygen metabolites (d-ROMs), as an index of products of reactive oxygen species (ROS), and biological antioxidant potential (BAP), as an index of antioxidant potential. We also investigated the associations between d-ROMs or BAP and the risk factors for lifestyle-related diseases or metabolic syndrome-associated factors to evaluate their usefulness in preventive medicine. There were 442 subjects who underwent health checkup examination in our facilities. In addition to standard medical checkup items, we analyzed d-ROMs, BAP, brachial-ankle pulse wave velocity, high-sensitivity C-reactive protein level and visceral fat area (VFA) visualized on a computed tomography scan. The mean d-ROM value in females was significantly higher than that in males. There was a positive correlation between the d-ROM and VFA levels. On correlation analysis, there was a negative correlation between the d-ROM and creatinine levels. As factors that influence d-ROMs, the level of VFA was selected, suggesting the significance of oxidative stress measurement with d-ROMs. In addition, there was a positive correlation between d-ROMs and BAP values. Further research is required to resolve whether increased production of ROS or the antioxidant potential that can compensate for such an increase of ROS is more important in vivo.

Applying a deep learning based CAD scheme to segment and quantify visceral and subcutaneous fat areas from CT images

NASA Astrophysics Data System (ADS)

Wang, Yunzhi; Qiu, Yuchen; Thai, Theresa; Moore, Kathleen; Liu, Hong; Zheng, Bin

2017-03-01

Abdominal obesity is strongly associated with a number of diseases and accurately assessment of subtypes of adipose tissue volume plays a significant role in predicting disease risk, diagnosis and prognosis. The objective of this study is to develop and evaluate a new computer-aided detection (CAD) scheme based on deep learning models to automatically segment subcutaneous fat areas (SFA) and visceral (VFA) fat areas depicting on CT images. A dataset involving CT images from 40 patients were retrospectively collected and equally divided into two independent groups (i.e. training and testing group). The new CAD scheme consisted of two sequential convolutional neural networks (CNNs) namely, Selection-CNN and Segmentation-CNN. Selection-CNN was trained using 2,240 CT slices to automatically select CT slices belonging to abdomen areas and SegmentationCNN was trained using 84,000 fat-pixel patches to classify fat-pixels as belonging to SFA or VFA. Then, data from the testing group was used to evaluate the performance of the optimized CAD scheme. Comparing to manually labelled results, the classification accuracy of CT slices selection generated by Selection-CNN yielded 95.8%, while the accuracy of fat pixel segmentation using Segmentation-CNN yielded 96.8%. Therefore, this study demonstrated the feasibility of using deep learning based CAD scheme to recognize human abdominal section from CT scans and segment SFA and VFA from CT slices with high agreement compared with subjective segmentation results.

Pigeon peas as a supplement for lactating dairy cows fed corn silage-based diets.

PubMed

Corriher, V A; Hill, G M; Bernard, J K; Jenkins, T C; West, J W; Mullinix, B G

2010-11-01

Holstein rumen-cannulated cows [n=7; initial body weight (BW) 640.56±71.43 kg] were fed a corn silage basal diet with 1 of 3 concentrates (C=control; P10=10% pigeon peas; P20=20% pigeon peas). Cows were randomly assigned to treatments in a replicated 3×3 Latin square and individually fed using Calan gates. Each experimental period was 21 d with 7 d for adaption and 14 d for sample collection. Ruminal fluid samples were taken the last day of each experimental period and analyzed for pH, ammonia, long-chain fatty acids, and volatile fatty acids (VFA). Consecutive a.m. and p.m. milk samples were taken during the last 2 wk of the 21-d period and analyzed for fat, protein, long-chain fatty acids, and somatic cell count. Dry matter intake (kg/d) was reduced during the second period and was greater for P10 diets. Milk protein was greater for cows fed P20 compared with P10. Energy-corrected milk was greater for cows fed the control diet compared with P10. Treatment had no effect on milk yield. Ruminal fluid pH decreased over sampling times; however, pH remained at or above 5.5. Diets did not affect ruminal fluid pH; however, pH was different for sampling periods. Ruminal ammonia decreased until 8h postfeeding at which time it peaked consistent with changes in ammonia concentrations that usually peak 3 to 5h postfeeding on diets high in plant proteins. Dietary treatments altered ruminal fluid VFA with reduced concentrations of acetate and greater concentrations of propionate for control diet, resulting in reduced acetate:propionate ratio. Isobutyrate exhibited an hour by treatment interaction, in which isobutyrate decreased until 8h postfeeding and then tended to be greater for P10 than for other treatments. Animals fed the P10 diet had greater concentrations of ruminal isovalerate. Ruminal cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acid (CLA) isomers were not affected by dietary treatments. The P10 diet had greatest ruminal synthesis of cis-9,trans-11, but control cows had greatest ruminal synthesis of trans-10,cis-12. Milk CLA isomers were similar among treatments. Trends were observed for greater cis-9,trans-11 and trans-10,cis-12 for the P10 diet. Pigeon peas may be used as a protein supplement in dairy diets without affecting milk production, dry matter intake, or ruminal environment when they replace corn and soybean meal. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Influence of extruded soybeans with or without bicarbonate on milk performance and fatty acid composition of goat milk.

PubMed

Schmidely, P; Morand-Fehr, P; Sauvant, D

2005-02-01

The effects of extruded soybeans (ESB) included at 0, 10, or 20% of dry matter (DM) of the diet in combination with sodium bicarbonate (0 vs. 1% bicarbonate added to DM) on rumen fermentation characteristics, production parameters, and fatty acid (FA) profiles of milk fat were examined in 30 midlactation goats and 6 rumen-cannulated goats fed high-concentrate diets (30:70 forage-to-concentrate ratio) ad libitum in a 3 x 2 factorial design. Diets were fed as total mixed rations. The trial lasted 13 wk with the final 9 wk as the test period. Milk yield and composition were recorded each week throughout the trial. Individual samples of milk were taken in wk 4, 7, 10, 11, and 13 to determine FA profile of milk fat. Dry matter intake and intake of net energy for lactation were not affected by dietary treatments. Feeding ESB did not modify ruminal pH or volatile fatty acids concentration in the rumen fluid, but it increased the molar proportion of propionate. Feeding ESB increased fat-corrected milk, milk fat content, and fat yield compared with the control diets. There was no change in milk protein content when ESB were fed. Feeding ESB increased the proportions of oleic, linoleic, and linolenic acids in milk fat at the expense of most of the saturated FA. It also increased the n-6 to n-3 FA ratio of milk. The largest changes in milk yield and milk composition were generally obtained with ESB included at 20% of DM. The addition of sodium bicarbonate tended to increase ruminal pH, VFA concentrations in the rumen fluid, and the molar proportions of acetate. The addition of sodium bicarbonate increased milk fat content and fat yield, with no change in milk FA composition. It is concluded that during midlactation, the inclusion of ESB to 20% of DM prevented low milk fat content for goats fed high-concentrate diets, with no decrease in milk protein content. The addition of sodium bicarbonate may enhance the effects of ESB on milk fat content and fat yield.

Yeast culture increased plasma niacin concentration, evaporative heat loss, and feed efficiency of dairy cows in a hot environment.

PubMed

Dias, Julia D L; Silva, Rayana B; Fernandes, Tatiane; Barbosa, Eugenio F; Graças, Larissa E C; Araujo, Rafael C; Pereira, Renata A N; Pereira, Marcos N

2018-04-04

The supplementation of dairy cows with yeast culture may increase diet digestibility, plasma niacin concentration, heat dissipation, and lactation performance. Our objective was to evaluate the response of Holstein cows in late lactation (234 ± 131 d in milk) to dead yeast culture (YC, 15 g/d, Factor SC, GRASP, Saccharomyces cerevisiae) during Brazilian summer (temperature-humidity index >68 for 92.2% of the time). Thirty-two cows were individually fed a standard total mixed ration for 14 d and control (CTL) or YC treatments for 35 d, in a covariate adjusted complete randomized block design. Response was evaluated in wk 5 or as repeated measures over time. Cows were milked 3 times per day and treatments (YC or placebo) were orally dosed to each cow before each milking. Plasma niacin was 1.50 for CTL and 1.66 µg/mL for YC. The YC reduced rectal temperature, respiration rate, and skin temperature, whereas it tended to increase sweating rate. The proportion of cows with rectal temperature ≥39.2°C on CTL and YC was, respectively, 8 and 0% at 0730 h, 52 and 25% at 1500 h, and 35 and 26% at 2200 h. Plasma glucose was increased by YC. The total-tract apparent digestibility of nutrients, plasma urea N concentration, molar proportion of ruminal VFA, and urinary allantoin excretion were not affected by YC. Cows fed YC were less selective against feed particles >19 mm in the morning, in the afternoon were more selective against long feed particles and in favor of particles <8 mm, and refused short particles at night. Milk yield was not different (30.5 kg/d for CTL and 30.2 kg/d for YC). Feeding YC reduced dry matter intake (20.3 vs. 19.4 kg/d) and the digestible organic matter intake (15.6 vs. 13.9 kg/d). The inclusion of YC increased the ratios of milk to dry matter intake (1.50 vs. 1.64) and energy-corrected milk to dry matter intake (1.81 vs. 1.98). The covariate adjusted body weight (648 kg) and body condition score (3.0) did not differ. Milk solids yields and concentrations, linear somatic cell count, and milk urea N were also similar. The supplementation of YC increased plasma niacin concentration, body heat loss, and feed efficiency of late lactation dairy cows by reducing intake at similar milk yield. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Forage and sugar in dairy calves' starter diet and their interaction on performance, weaning age and rumen fermentation.

PubMed

Beiranvand, H; Ghorbani, G R; Khorvash, M; Kazemi-Bonchenari, M

2014-06-01

The effects of sugar and forage inclusion in calves' starter and their interaction on animal performance and rumen fermentation parameters were investigated. Twenty-eight neonatal Holstein male calves 3 days of age with average body weights of 42 ± 4 kg were allocated to four different treatments. All calves were fed a similar basal diet consisting of milk and concentrate. The experimental treatments were: (i) basal diet with no supplementation (Control, hereafter designated by C), (ii) basal diet plus 5% granular sugar cane (Sugar, designated by S), (iii) basal diet plus 5% forage (Forage, designated by F) and (iv) basal diet plus 5% forage with 5% granular sugar cane (F × S). Supplement ingredients were used on a dry matter (DM) basis. Rumen fluid parameters were measured twice on days 35 and 70 of the study period. The calves were weaned when they could consume 1 kg of starter for three consecutive days. The results show that starter intake was not affected by treatment; however, the lowest ADG was observed with calves in the sugar treatment. Weaning age was affected by treatments, and forage showed to reduce milk consumption period down to its shortest. Forage-sugar interaction was found to have no effects on animal performance. The structural body indices as well as the health status of the calves were similar in different treatments. Rumen pH did not differ among the treatment groups. Among the rumen parameters, total VFA concentration and molar proportions of butyrate and propionate did not exhibit any significant differences among the treatments. However, ruminal acetate concentration decreased in calves that fed sugar cane during the early weeks of the study period. Comparison of forage and sugar included in the starter diets revealed that forage reduced weaning age, while sugar cane had a negative effect on calves' performance. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Direct-fed microbials containing lactate-producing bacteria influence ruminal fermentation but not lactate utilization in steers fed a high-concentrate diet.

PubMed

Kenney, N M; Vanzant, E S; Harmon, D L; McLeod, K R

2015-05-01

Direct-fed microbials (DFM) have been shown to improve gain and growth efficiency and also modulate ruminal fermentation. In Exp. 1,72 beef steers were used to compare a lactate-producing bacterial (LAB) DFM consisting primarily of Lactobacillus acidophilus and Enterococcus faecium,and a lactate-producing and lactate-utilizing (LAB/LU) DFM consisting primarily of L. acidophilus and Propionibacterium both fed at 10(9) cfu/d. Steers were fed a corn-based finishing diet for 153 d and then slaughtered for collection of carcass characteristics. In Exp. 2, 12 ruminally cannulated steers were fed acorn-based finishing diet and treated with 10(9) cfu/d of LAB DFM. Rumen fluid was sampled on d 14 and 28 over a 12-h period. Steers were ruminally dosed with a 2-L solution of neutralized DL-lactate (0.56 M)and Cr-EDTA (13.22 M) 3 h postfeeding on d 15 and 29. Ruminal samples were collected at 10- and 20-minintervals for the first and second hour postdosing. No differences (P ≥ 0.14) between control (CON) and LAB for DMI, ADG, growth efficiency, or carcass characteristics were observed. Dry matter intake was greater (P = 0.04) for LAB/LU than LAB from d 0 to 28 but did not differ (P ≥ 0.29) thereafter. Average daily gain was greater (P = 0.04) and efficiency tended(P = 0.06) to be greater for LAB than LAB/LU over the entire 153 d. In Exp. 2, total VFA concentration and molar proportions of butyrate were unaffected(P ≥ 0.24). Molar proportions of acetate exhibited a DFM by hour interaction (P = 0.04); however, on average, molar proportion of acetate was 4.4% greater for DFM. Conversely, DFM did not affect the molar proportion of propionate (P = 0.39). On average,molar proportions of propionate tended to increase(P = 0.07), and acetate tended to decrease (P = 0.07)across days. Mean daily ruminal pH was similar for CON on d 14 and 28, whereas mean pH increased from d 14 to 28 for DFM (DFM × day; P = 0.08).Minimum pH remained unchanged for CON over time but increased from d 14 to 2 for DFM (DFM × day;P = 0.10). Maximum pH decreased from d 14 to 28 in CON but increased over time with DFM (DFM × day;P = 0.05). DL- and L-lactate utilization were unaffected by DFM (P ≥ 0.33) or day (P ≥ 0.50). Although the LAB DFM did not impact growth performance, itd id modulate ruminal fermentation, as evidenced by shifts in ruminal VFA profile and pH; however, DFM did not appear to influence ruminal lactate utilization.

Effect of calcium oxide inclusion in beef feedlot diets containing 60% dried distillers grains with solubles on ruminal fermentation, diet digestibility, performance, and carcass characteristics.

PubMed

Nuñez, A J C; Felix, T L; Lemenager, R P; Schoonmaker, J P

2014-09-01

Two experiments were conducted to determine the effect of increasing dietary CaO on ruminal fermentation, diet digestibility, performance, and carcass characteristics of feedlot steers fed 60% dried distillers grains with solubles ( DDGS: ). In Exp. 1, 120 steers were allotted by weight (355 ± 7.9 kg) to 1 of 4 treatments containing 60% DDGS, 20% corn silage, 13.5 to 14.4% ground corn, 4% supplement, and 0 to 2.5% limestone on DM basis to determine the effects of CaO on performance and carcass characteristics. Treatments consisted of 0, 0.8, 1.6, or 2.4% CaO inclusion in the diet (DM basis), with CaO replacing limestone. Steers were slaughtered at a target BW of approximately 641 kg. In Exp. 2, 4 steers (initial BW = 288 ± 3 kg) were randomly allotted to the same diets in a 4 × 4 Latin square design (14-d periods) to determine the effects of CaO on ruminal pH, VFA, and nutrient digestibility. Statistical analyses were conducted using the MIXED procedure of SAS. Inclusion of CaO at 0.8, 1.6, and 2.4% increased ADG by 5.0, 3.9, and 0%, respectively, compared to 0% CaO (quadratic; P = 0.03). Intake was linearly decreased (P = 0.04) and G:F was linearly increased (P = 0.02) by CaO inclusion. Dressing percentage increased as CaO increased from 0 to 1.6% and then decreased for 2.4% CaO (quadratic; P < 0.01). In Exp. 2, steers fed 0% CaO had the greatest prefeeding ruminal pH, steers fed 0 and 0.8% CaO exhibited the most rapid postfeeding decline in ruminal pH, and steers fed 2.4% CaO exhibited a relatively stable ruminal pH throughout the 24-h period (treatment × time; P ≤ 0.01). Acetate, butyrate, and total VFA concentrations increased linearly (P ≤ 0.05) at 0, 3, 6, and 12 h postfeeding with increasing CaO. Propionate at 3 h postfeeding increased from 0 to 1.6% CaO and decreased from 1.6 to 2.4% CaO (quadratic; P = 0.10). Urine pH increased linearly (P ≤ 0.01) while urine output and urine ammonia decreased linearly (P ≤ 0.05) as CaO inclusion increased. Apparent NDF digestibility tended to increase (P = 0.07) and ADF digestibility did (P = 0.01) increase linearly with increasing concentrations of CaO. In conclusion, CaO improved ruminal pH variation, increased fiber digestibility, and decreased metabolic acid load in cattle fed 60% DDGS-based diets. Inclusion of CaO up to 1.6% was effective in improving performance of feedlot cattle.

Effects of aerobic exercise training on serum sex hormone binding globulin, body fat index, and metabolic syndrome factors in obese postmenopausal women.

PubMed

Kim, Jong-Won; Kim, Do-Yeon

2012-12-01

The percentage of obese postmenopausal women with metabolic syndrome is rising, and physical factors associated with the metabolic syndrome prevalence or incidence are also rising, including high body mass index (BMI), visceral fat area (VFA), low plasma sex hormone-binding globulin (SHBG) levels, and low cardiorespiratory fitness. Therefore, we investigated the influence of aerobic exercise on SHBG, body fat index (BFI), and metabolic syndrome factors in obese postmenopausal Korean women. Thirty healthy postmenopausal, women aged 53.46 ± 2.4 years and with over 32% body fat, were randomly assigned to an aerobic exercise group (EX; n=15) or to a "nonexercise" control (Con; n=15) group. The primary outcome measurements were serum SHBG, lipid profiles, insulin levels, and metabolic syndrome factors. Secondary outcome measurements were body composition, VFA, blood pressure (BP), and homeostasis model assessment of insulin resistance (HOMA-IR). Posttraining body weight and BFI (P<0.05), total cholesterol, glucose, and insulin levels (P<0.01), BP, and HOMA-IR (P<0.001) decreased, whereas SHBG (P<0.001) and metabolic syndrome factors (P<0.01) improved in the exercise group but not in the control group. SHBG levels also showed a significant positive correlation with high-density lipoprotein cholesterol (HDL-C) and significant negative correlations withglucose, diastolic blood pressure, fat mass, BMI, and percent body fat (P<0.05). Our findings indicate that aerobic exercise improves body composition, SHBG, insulin levels, and metabolic syndrome factors. These findings suggest that in obesepostmenopausal Korean women, 16 weeks of aerobic exercise is effective for preventing the metabolic syndrome caused by obesity.

In vitro study of the age-dependent caecal fermentation pattern and methanogenesis in young rabbits.

PubMed

Piattoni, F; Demeyer, D I; Maertens, L

1996-01-01

The caecal fermentation pattern, including methanogenesis, was studied in young rabbits using in vitro batch incubations. Six conventional litters of eight rabbits each were used. At the age of 22, 25, 28, 32, 36, 42 and 56 days, an animal was slaughtered from each litter and its caecal contents were used for in vitro batch incubations at 39 degrees C/24 h. The incubated samples were analysed for volatile fatty acids (VFA), methane, hydrogen, ammonia nitrogen (NH3-N) and lactic acid (LA). The net total in vitro VFA production did not differ clearly with age, although a significant decrease was observed on day 36, reflecting the reduced zootechnical performances probably related to an infection with Clostridium spiroforme that occurred in the same period. The molar proportions of butyrate and propionate formed a change in the opposite direction with age, starting with a sudden shift from propionate to butyrate at day 25. In vitro NH3-N production was suggestive of a progressive and significant decrease with age; in vitro LA production was always low. Methane production was almost absent from fermentation until 32 days of age, after which it suddenly shifted from 1.6 to 52.0 mumol/flask/day and increased further with age. A significant litter effect on methanogenesis was observed which suggested the existence of a genetic effect. The hydrogen production was quite low and decreased significantly from day 36 with increasing methanogenesis. The calculated hydrogen recoveries showed a gradual increase from day 32 and were positively correlated (r = 0.92) with methane production. In conclusion, it would seem that in young suckling rabbits, reductive acetogenesis is a major characteristic of caecal fermentation, to be replaced gradually and partially by methanogenesis with the increasing intake of solid feed.

Lifetime shift work exposure: association with anthropometry, body composition, blood pressure, glucose and heart rate variability.

PubMed

Souza, Breno Bernardes; Monteze, Nayara Mussi; de Oliveira, Fernando Luiz Pereira; de Oliveira, José Magalhães; de Freitas Nascimento, Silvia; Marques do Nascimento Neto, Raimundo; Sales, Maria Lilian; Souza, Gabriela Guerra Leal

2015-03-01

To evaluate the association between lifetime exposure to shift work and blood pressure, fasting glucose (FG), anthropometric variables, body composition and heart rate variability (HRV). Male shift workers (N=438) were evaluated using principal component (PC) analysis. The variables used were: weight, body mass index (BMI), waist circumference (WC), neck circumference (NC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat mass (BFKg), body fat percentage (BF%), visceral fat area (VFA), FG, systolic (SBP) and diastolic blood pressure (DBP), and HRV variables. ECG was performed, extracting heart rate (HR), root mean square of the successive differences (RMSSD), high frequency (HF), low frequency (LF) and the LF/HF ratio. Using linear regression models, the lifetime shift work exposure was associated with each PC. Five PCs were obtained, which accounted for 79.6% of the total variation of the data. PC1 (weight, BMI, WC, NC, HC, WHR, WHtR, BFKg, BF% and VFA) was designated as body obesity; PC2 (HF, RMSSD and LF) as good cardiac regulation; PC3 (SBP and DBP) as blood pressure; PC4 (LF/HF ratio and HR) as bad cardiac regulation and PC5 (WHR and FG) as insulin resistance. After age adjustment, the regression analysis showed that lifetime shift work was negatively associated with PC2 and positively associated with PC3. The association of lifetime shift work exposure with PC2 and PC3 suggests that shift work promotes unfavourable changes in autonomic cardiac control related to a decrease in parasympathetic modulation and an increase in blood pressure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Syntrophic acetate oxidation in industrial CSTR biogas digesters.

PubMed

Sun, Li; Müller, Bettina; Westerholm, Maria; Schnürer, Anna

2014-02-10

The extent of syntrophic acetate oxidation (SAO) and the levels of known SAO bacteria and acetate- and hydrogen-consuming methanogens were determined in sludge from 13 commercial biogas production plants. Results from these measurements were statistically related to the prevailing operating conditions, through partial least squares (PLS) analysis. This revealed that high abundance of microorganisms involved in SAO was positively correlated with relatively low abundance of aceticlastic methanogens and high concentrations of free ammonia (>160 mg/L) and volatile fatty acids (VFA). Temperature was identified as another influencing factor for the population structure of the syntrophic acetate oxidising bacteria (SAOB). Overall, there was a high abundance of SAOB in the different digesters despite differences in their operating parameters, indicating that SAOB are an enduring and important component of biogas-producing consortia. Copyright © 2013 Elsevier B.V. All rights reserved.

Biogas production from municipal solid wastes using an integrated rotary drum and anaerobic-phased solids digester system.

PubMed

Zhu, Baoning; Zhang, Ruihong; Gikas, Petros; Rapport, Joshua; Jenkins, Bryan; Li, Xiujin

2010-08-01

This research was conducted to develop an integrated rotary drum reactor (RDR)-anaerobic-phased solids (APS) digester system for the treatment of municipal solid waste (MSW) to produce biogas energy and achieve waste reduction. A commercial RDR facility was used to provide a 3-d pretreatment and sufficient separation of the organics from MSW and then the organics were digested in a laboratory APS-digester system for biogas production. The organics generated from the RDR contained 50% total solids (TS) and 36% volatile solids (VS) on wet basis. The APS-digester was started at an organic loading rate (OLR) of 3.1 gVS L(-1) d(-1) and operated at three higher OLRs of 4.6, 7.7 and 9.2 gVS L(-1) d(-1). At the OLR of 9.2 gVS L(-1) d(-1) the system biogas production rate was 3.5 L L(-1) d(-1) and the biogas and methane yields were 0.38 and 0.19 L gVS(-1), respectively. Anaerobic digestion resulted in 38% TS reduction and 53% VS reduction in the organic solids. It was found that the total VFA concentration reached a peak value of 15,000 mg L(-1) as acetic acid in the first 3d of batch digestion and later decreased to about 500 mg L(-1). The APS-digester system remained stable at each OLRs for over 100d with the pH in the hydrolysis reactors in the range of 7.3-7.8 and the pH in the biogasification reactor in 7.9-8.1. The residual solids after the digestion had a high heating value of 14.7 kJ gTS(-1). Copyright 2010 Elsevier Ltd. All rights reserved.

Biological upgrading of volatile fatty acids, key intermediates for the valorization of biowaste through dark anaerobic fermentation.

PubMed

Singhania, Reeta Rani; Patel, Anil Kumar; Christophe, Gwendoline; Fontanille, Pierre; Larroche, Christian

2013-10-01

VFAs can be obtained from lignocellulosic agro-industrial wastes, sludge, and various biodegradable organic wastes as key intermediates through dark fermentation processes and synthesized through chemical route also. They are building blocks of several organic compounds viz. alcohol, aldehyde, ketones, esters and olefins. These can serve as alternate carbon source for microbial biolipid, biohydrogen, microbial fuel cells productions, methanisation, and for denitrification. Organic wastes are the substrate for VFA platform that is of zero or even negative cost, giving VFA as intermediate product but their separation from the fermentation broth is still a challenge; however, several separation technologies have been developed, membrane separation being the most suitable one. These aspects will be reviewed and results obtained during anaerobic treatment of slaughterhouse wastes with further utilisation of volatile fatty acids for yeast cultivation have been discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Multi-phased anaerobic baffled reactor treating food waste.

PubMed

Ahamed, A; Chen, C-L; Rajagopal, R; Wu, D; Mao, Y; Ho, I J R; Lim, J W; Wang, J-Y

2015-04-01

This study was conducted to identify the performance of a multi-phased anaerobic baffled reactor (MP-ABR) with food waste (FW) as the substrate for biogas production and thereby to promote an efficient energy recovery and treatment method for the wastes with high organic solid content through phase separation. A four-chambered ABR was operated at an HRT of 30 days with an OLR of 0.5-1.0 g-VS/Ld for a period of 175 days at 35 ± 1°C. Consistent overall removal efficiencies of 85.3% (CODt), 94.5% (CODs), 89.6% (VFA) and 86.4% (VS) were observed throughout the experiment displaying a great potential to treat FW. Biogas generated was 215.57 mL/g-VS removed d. Phase separation was observed and supported by the COD and VFA trends, and an efficient recovery of bioenergy from FW was achieved. Copyright © 2015 Elsevier Ltd. All rights reserved.

Epithelial response to high-grain diets involves alteration in nutrient transporters and Na+/K+-ATPase mRNA expression in rumen and colon of goats.

PubMed

Metzler-Zebeli, B U; Hollmann, M; Sabitzer, S; Podstatzky-Lichtenstein, L; Klein, D; Zebeli, Q

2013-09-01

Emerging evidence at the mRNA level indicates that feeding high-grain diets to ruminants leads to coordinated changes in the molecular response of the rumen epithelium. Yet, epithelial adaptation of the hindgut to increasing dietary grain levels has not been established in ruminants. Therefore, the objective of this study was to characterize alterations in mRNA expression associated with nutrient transport and electrochemical gradients in rumen and colon epithelium, and rumen morphology in growing goats fed different grain levels. Goats (n = 6) were fed diets with increasing levels of 0, 30, or 60% barley grain for 6 wk. Goats were euthanized 2 h after their last feeding, and digesta and tissue samples of the cranial part of the ventral rumen and proximal colon were collected. Goats fed the 60% grain diet exhibited a lower ruminal and colonic pH (P < 0.01) and a greater colonic total VFA concentration (P < 0.05) compared with those fed the 0 and 30% grain diets. As response to the decreased ruminal pH, goats fed the 60% grain diet had a greater (P < 0.05) keratinization and thicker stratum corneum of the rumen epithelium than goats fed the 0 and 30% grain diets. The 60% grain diet upregulated (P < 0.05) MCT1 expression by 45% and downregulated (P < 0.05) the expression of MCT4 and SGLT1 by 28 and 50%, respectively, in rumen epithelium compared with the 0 and 30% grain diets. Accordingly, goats fed the 60% grain diet had a greater (P < 0.05) expression of MCT1 and ATP1A1 in colon epithelium than goats fed the 0 and 30% grain diets. Regression analyses showed negative relationships (R(2) = 0.35 to 0.87, P < 0.05) of MCT1 and ATP1A1 expression in rumen and colon epithelium and thickening of ruminal stratum corneum to decreasing luminal pH values, suggesting greater mRNA expression at lower pH. In contrast, MCT4 expression in rumen epithelium positively correlated to luminal pH (R(2) = 0.95, P < 0.01). In conclusion, results of this model study indicated that with the greatest grain level rumen and colon molecular epithelial responses may have been related to counteract the consequences of luminal acidification on intracellular homeostasis in epithelial cells and concomitantly to increase systemic absorption of VFA.

Evaluation of feed value of a by-product of pickled radish for ruminants: analyses of nutrient composition, storage stability, and in vitro ruminal fermentation.

PubMed

Jeon, Seoyoung; Sohn, Keun-Nam; Seo, Seongwon

2016-01-01

By-products of pickled radish (BPR) are considered food waste. Approximately 300 g/kg of the total mass of raw materials becomes BPR. Production of pickled radish has grown continuously and is presently about 40,000 metric tons annually in Korea. The objective of the present study was thus to explore the possibility of using BPR as a ruminant feed ingredient. BPR contained a large amount of moisture (more than 800 g/kg) and ash, and comprised mostly sodium (103 g/kg DM) and chloride (142 g/kg DM). On a dry matter basis, the crude protein (CP) and ether extract (EE) levels in BPR were 75 g/kg and 7 g/kg, respectively. The total digestible nutrient (TDN) level was 527 g/kg and the major portion of digestible nutrients was carbohydrate; 88 % organic matter (OM) was carbohydrate and 65 % of total carbohydrate was soluble or degradable fiber. The coefficient of variation (CV) of nutrient contents among production batches ranged from 4.65 to 33.83 %. The smallest CV was observed in OM, and the largest, in EE. The variation in CP content was relatively small (10.11 %). The storage stability test revealed that storage of BPR at 20 °C (room temperature) might not cause spoilage for 4 d, and possibly longer. If BPR is refrigerated, spoilage can be deferred for 21 d and longer. The in vitro ruminal fermentation study showed that substitution of annual ryegrass straw with BPR improved ruminal fermentation, as evidenced by an increase in VFA concentration, DM degradability, and total gas production. The major portion of nutrients in BPR is soluble or degradable fiber that can be easily fermented in the rumen without adverse effects, to provide energy to ruminant animals. Although its high sodium chloride content needs to be considered when formulating a ration, BPR can be successfully used as a feed ingredient in a ruminant diet, particularly if it is one component of a total mixed ration.

Effect of monensin withdrawal on intake, digestion, and ruminal fermentation parameters by Bos taurus indicus and Bos taurus taurus steers consuming bermudagrass hay.

PubMed

Bell, N L; Callaway, T R; Anderson, R C; Franco, M O; Sawyer, J E; Wickersham, T A

2017-06-01

Effects of monensin withdrawal and cattle subspecies on the utilization of bermudagrass hay (14.3% CP, 72.3% NDF, and 36.9% ADF) were evaluated using ruminally cannulated steers (5 [BI] and 5 [BT]). Subspecies were concurrently subjected to a 2-period, 2-treatment crossover design. Treatments consisted of either 0 mg·steer·d-1 monensin with no previous monensin feeding (CON) or withdrawal from 200 mg·steer·d-1 monensin (MON) fed individually in 0.91 kg dried distillers' grains with solubles for 42 d. Withdrawal was evaluated for a 28-d period. Ruminal fluid was collected 2 h after feeding on d 0, 1, 4, 7, 14, and 21 after withdrawal for determination of pH, VFA, ruminal NH-N (RAN), rate of NH production, and CH production rate. Hay, ort, and fecal grab samples were collected d 23 through 28 after withdrawal for determination of intake and digestion. No subspecies × monensin, subspecies × day, or subspecies × monensin × day interactions were observed ( ≥ 0.11). An effect of day after monensin withdrawal was observed ( < 0.01) for total VFA concentration, with an increase following withdrawal followed by a decrease and then stabilization. Monensin × day after monensin withdrawal interactions ( ≤ 0.01) were observed for the acetate:propionate (A:P) ratio and molar percent of acetate and propionate. There was a decrease in molar percent of propionate between d 1 and 4 from 19.1 to 18.0; however, it remained greater ( ≤ 0.10) for MON than CON through d 7. Withdrawal increased molar percent of acetate from 68.3 to 69.8 between d 0 and 4 for MON steers. The A:P ratio was less ( ≤ 0.01) on d 0 for MON than for CON (3.4 vs. 4.0), but by d 4, it increased to 3.8 and was not different ( = 0.14) from CON. By d 14, no differences ( ≥ 0.88) remained for acetate, propionate, or the A:P ratio. After monensin withdrawal, monensin reduced ( < 0.01) RAN by 12.3% (2.09 vs. 1.83 m for CON and MON, respectively). Monensin withdrawal and cattle subspecies had no effect ( ≥ 0.23) on rate of NH production or CH production rate. Monensin withdrawal had no effect ( ≥ 0.45) on intake or digestibility parameters. Greater forage OM intake ( = 0.09; 21.2 vs. 19.2 g/kg BW) and OM digestibility ( < 0.01; 72.4 vs. 63.0%) resulted in greater ( < 0.01) total digestible OM intake (16.8 vs. 13.2 g/kg BW) in BT steers than in BI steers. These results suggest that BT steers are better able to utilize bermudagrass hay than BI steers. Upon monensin withdrawal, steers previously fed monensin continue to have a reduced A:P ratio for at least 7 d.

The effect of nitrate and monensin on in vitro ruminal fermentation.

PubMed

Capelari, M; Powers, W

2017-11-01

Two experiments evaluated the effect of calcium ammonium nitrate decahydrate (calcium nitrate [NIT]) and monensin sodium (MON) on in vitro fermentation parameters of 2 contrasting diets (100:0 and 10:90 forage-to-concentrate ratios). Diet addition of NIT (0, 1.25, and 2.5 g/100 g DM) and MON (0, 3, and 6 mg/L) were tested alone and combined (9 treatments total; 5 bottles per treatment). Mixed ruminal microorganisms were incubated in anaerobic media containing 0.5 g of substrate diet, 1 of 9 treatments, and 40 mL buffer solution. Incubations were performed in batch cultures for 48 h at 39°C. Headspace gas volume was measured and sampled at 4, 8, 12, 24, and 48 h, and the VFA profile was assessed at the end of the experiment. Total gas production was reduced by NIT (87.9 vs. 94.6 mL; < 0.01) and MON (78.6 vs. 94.6 mL; < 0.01) and, in Exp. 2, further reduced by NIT+MON when the additives were combined (161.1 vs. 196.9 mL; < 0.01). Methane production from control in Exp. 1 and Exp. 2 averaged 9.1 and 15.3 mL, respectively, and was decreased by NIT (3.4 and 8.3 mL in Exp. 1 and Exp. 2, respectively; P < 0.01), MON (4.1 and 7.7 mL; in Exp. 1 and Exp. 2, respectively; < 0.01) and NIT+MON (1.1 and 1.5 mL; in Exp. 1 and Exp. 2, respectively; < 0.01). Both experiments demonstrated a significant increase in nitrous oxide (NO; < 0.01) when NIT was added. Compared to the control treatment, IVDMD was reduced when NIT+MON was added at the higher doses in EXP1 (31.7 vs. 37.4%; < 0.01) and EXP2 (76.6 vs. 79.9 %; < 0.01). Net VFA production was not affected by treatments ( > 0.10), but molar proportions of acetate and butyrate were reduced by MON ( < 0.01). Propionate molar proportion was increased in both experiments by MON ( < 0.01) and further increased in Exp. 2 when the additives were combined at lower doses ( < 0.01). Compared to the control treatment, the acetate:propionate (A:P) ratio was reduced by MON in Exp. 1(1.2 vs. 2.8; < 0.01) and Exp. 2 (1.0 vs. 2.3; < 0.01). Fermentation efficiency (%) was increased by MON (81.7 vs. 73.7%; < 0.01) and further increased in Exp. 2 when the additives were combined at lower doses (87.2 vs. 76.6%; < 0.01). The combination of NIT and MON in 2 contrasting diets proved beneficial by altering fermentation products toward lower CH and more propionate; however, the addition of NIT consistently increased NO production. Negative effects of the additives on IVDMD were found only when the additives were combined at higher doses.

A strategy to improve nitrogen utilization, reduce environmental impact, and increase performance and antioxidant capacity of fattening lambs using pomegranate peel extract.

PubMed

Rajabi, M; Rouzbehan, Y; Rezaei, J

2017-01-01

Dietary natural plant secondary metabolites (PSM) extracted from a pomegranate peel (PP) byproduct have the potential to improve milk yield and the milk fatty acid profile of dairy cows. This experiment was performed to assess the influence of different dietary levels of PP extract (PPE) on feedlot performance, ruminal status, nutrient utilization, and antioxidant status in fattening Moghani lambs. Thirty-two lambs (initial BW of 22 ± 1.2 kg) were used in a completely randomized design with a 72-d period and 4 treatments: PPE0 (no extract), PPE15 (15 mL PPE/kg of diet DM), PPE30 (30 mL PPE/kg of diet DM), and PPE45 (45 mL PPE/kg of diet DM). Feed intake, lamb growth, diet digestibility, microbial nitrogen (N) synthesis (MNS), N retention, rumen parameters, and blood metabolites were determined. The addition of PPE to the diet of lambs had no effect on DMI (linear [L], = 0.96; quadratic [Q], = 0.65). In vivo digestibility coefficients of DM, OM, CP, and Ash-free NDF were not affected (L, ≥ 0.28; Q, ≥ 0.26) by different levels of PPE, but it increased ADG (L, = 0.045; Q, = 0.19) and G:F (L, = 0.046; Q, = 0.20). Rumen pH, VFA concentrations, and acetate-to-propionate ratio were not affected (L, ≥ 0.14; Q, ≥ 0.23) by PPE supplementation. Dietary inclusion of PPE decreased the ruminal concentration of ammonia N (L, = 0.014; Q, = 0.67), total protozoa enumeration (L, < 0.001; Q, = 0.043), population (L, < 0.001; Q, = 0.19), urinary N excretion (L, = 0.005; Q, = 0.26), whereas MNS (L, = 0.019; Q, = 0.23) and N retention (L, < 0.001; Q, = 0.66) increased. Feeding PPE had no effect (L, ≥ 0.11; Q, ≥ 0.17) on plasma concentrations of glucose, triglycerides, cholesterol, total protein, albumin, or albumin-to-globulin ratio. Blood urea N (L, = 0.021; Q, = 0.32) decreased with dietary addition of PPE, while total antioxidant capacity (TAC) in the rumen fluid (L, = 0.032; Q, = 0.64) and TAC in the blood (L, = 0.041; Q, = 0.51) increased. Overall, dietary inclusion of PPE, up to 45 mL/kg of diet DM, linearly improved animal growth, N retention, and antioxidant capacities of the blood and rumen fluid. The PPE is a safe natural additive for use in sheep diets that can help to reduce environmental pollution by reducing urinary N excretion.

Impact of hard vs. soft wheat and monensin level on rumen acidosis in feedlot heifers.

PubMed

Yang, W Z; Xu, L; Zhao, Y L; Chen, L Y; McAllister, T A

2014-11-01

Many feedlot finishing diets include wheat when the relative wheat prices are low. This study was conducted to examine the responses in ruminal pH and fermentation as well as site and extent of digestion from substituting soft or hard wheat for barley grain and to determine whether an elevated monensin concentration might decrease indicators of ruminal acidosis in feedlot heifers. Five ruminally cannulated beef heifers were used in a 5 × 5 Latin square with 2 × 2 + 1 factorial arrangement. Treatments included barley (10% barley silage, 86% barley, 4% supplement, with 28 mg monensin/kg DM) and diets where barley was substituted by either soft or hard wheat with either 28 or 44 mg monensin/kg diet DM. Intake of DM was not affected by grain source, whereas increasing monensin with wheat diets reduced (P < 0.02) DMI. Mean ruminal pH was lower (P < 0.04) and durations of pH < 5.8 and pH < 5.5 greater (P < 0.03) for wheat than for barley diets. However, ruminal pH was not affected by wheat type or monensin level. Total VFA concentrations were greater (P < 0.03) for wheat than barley diets with no effect of wheat type. The molar proportion of propionate was greater (P < 0.04), whereas butyrate (P < 0.01) and ratio of acetate to propionate tended to be lower (P < 0.09), with the high as compared to low level of monensin. Replacing barley with wheat in finishing diets did not affect the duodenal flow or the digestibility of OM, likely as a result of greater (P < 0.01) NDF digestion from barley offsetting the increased (P < 0.03) supply of digested starch from wheat. Feeding soft vs. hard wheat delivered a greater (P < 0.03) duodenal supply of OM and nonammonia N with no differences in total tract nutrient digestion. The increased monensin concentration decreased the flow of OM (P < 0.01), total N (P < 0.05), and microbial protein (P < 0.05) to the small intestine due to decreased DMI. These results indicated that hard and soft wheat exhibited digestive characteristics similar to barley, but ruminal pH measurements indicate that compared with barley, wheat increased the risk of ruminal acidosis. Although an increased level of monensin had limited impact on ruminal indicators of acidosis, an increase in propionate would be expected to improve efficiency of feed use by heifers fed wheat-based finishing diets.

Degradation parameters of amaranth, barley and quinoa in alpacas fed grass hay.

PubMed

Nilsen, B; Johnston, N P; Stevens, N; Robinson, T F

2015-10-01

This study was conducted to determine the compartment 1 (C1) characteristics of alpacas (fistulated male, 7 ± 1.5 years old, 61 ± 5 kg BW) fed grass hay (GH) supplemented with amaranth (AM), quinoa (Q) and barley (B) grains. Alpacas were provided water ad libitum while housed in metabolism crates. The GH and GH plus treatments were fed at 0700 every day. Treatment periods were for 14 days in which GH or GH plus one of the grain treatments were randomly allocated. On day 14, volatile fatty acids (VFA), pH and ammonia nitrogen (NH3 -N) were determined at 1, 3, 6, 10, 14, 18 and 24 h post-feeding. C1 degradation of each feed component was also determined with the alpacas being fed GH only and the samples incubated for 0, 2, 4, 8, 14, 24, 48 and 72 h. Dry matter (DM), neutral detergent fibre (NDF) and crude protein (CP) were determined and were divided into three categories: a = immediately soluble; b = the non-soluble but degradable; and u = non-degradable/unavailable, potential extent of degradation (PE), degradation rate (c) and effective degradation (ED). C1 passage rate was determined using acid detergent insoluble ash as a marker and was calculated to be 5.5%∙h-1. Total DM intake was highest (p < 0.05) for B and resulted in a higher (p < 0.05) CP intake. GH and AM were different in mean pH (6.81 and 6.66, respectively). B NH3 -N was greater (p < 0.05) than the other treatments. Total VFA was greatest (p < 0.05) for AM, with the greatest composition differences being a shift form acetate percentage to butyrate. DM, NDF and CP degradation was different across the treatments, where PE and ED were higher (p < 0.05) for the grain treatments. The pseudo-grains AM and Q had similar C1 degradation characteristics to B. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Ginkgo fruit extract as an additive to modify rumen microbiota and fermentation and to mitigate methane production.

PubMed

Oh, S; Shintani, R; Koike, S; Kobayashi, Y

2017-03-01

Ginkgo fruit, an unused byproduct of the ginkgo nut industry, contains antimicrobial compounds known as anacardic acids. Two major cultivars of ginkgo, Kyuju (K) and Tokuro (T), were evaluated for their potential as a feed additive for ruminants. In batch culture, we incubated a mixture of hay and concentrate in diluted rumen fluid with or without 1.6% (fruit equivalent) ginkgo fruit extract. We conducted another series of batch culture studies to determine the dose response of fermentation. We also conducted continuous culture using the rumen simulation technique (RUSITEC) with cultivar K and carried out a pure culture study to monitor the sensitivity of 17 representative rumen bacterial species to ginkgo extract and component phenolics. Although both K and T extracts led to decreased methane and increased propionate production, changes were more apparent with K extract, and were dose-dependent. Total gas production was depressed at doses ≥3.2%, suggesting that 1.6% was the optimal supplementation level. In RUSITEC fermentation supplemented with 1.6% ginkgo K, methane decreased by 53% without affecting total gas or total VFA production, but with decreased acetate and increased propionate. Disappearance of dry matter, neutral detergent fiber, and acid detergent fiber were not affected by ginkgo, but ammonia levels were decreased. Quantitative PCR indicated that the abundance of protozoa, fungi, methanogens, and bacteria related to hydrogen and formate production decreased, but the abundance of bacteria related to propionate production increased. MiSeq analysis (Illumina Inc., San Diego, CA) confirmed these bacterial changes and identified archaeal community changes, including a decrease in Methanobrevibacter and Methanomassiliicoccaceae and an increase in Methanoplanus. Pure culture study results supported the findings for the above bacterial community changes. These results demonstrate that ginkgo fruit can modulate rumen fermentation toward methane mitigation and propionate enhancement via microbial selection. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Indicators of induced subacute ruminal acidosis (SARA) in Danish Holstein cows.

PubMed

Danscher, Anne Mette; Li, Shucong; Andersen, Pia H; Khafipour, Ehsan; Kristensen, Niels B; Plaizier, Jan C

2015-07-17

The prevalence of subacute ruminal acidosis (SARA) in dairy cows is high with large impact on economy and welfare. Its current field diagnosis is based on point ruminal pH measurements by oral probe or rumenocentesis. These techniques are invasive and inaccurate, and better markers for the diagnosis of SARA are needed. The goal of this study was to evaluate clinical signs of SARA and to investigate the use of blood, faecal and urinary parameters as indicators of SARA. Six lactating, rumen cannulated, Danish Holstein cows were used in a cross-over study with three periods. The first and second periods included two cows on control diet and two cows on nutritional SARA challenge. The third period only included two cows on SARA challenge. Control diet was a conventional total mixed ration [45.5% dry matter (DM), 17.8% crude protein, 43.8% neutral detergent fibre, and 22.5% acid detergent fibre (DM basis)]. SARA challenge was conducted by substituting control diet with grain pellets (50% wheat/barley) over 3 days to reach 40% grain in the diet. Ruminal pH was measured continuously. Blood samples were collected once daily at 7 h after feeding. Samples of faeces and urine were collected at feeding, and at 7 and 12 h after feeding. Blood samples were analysed for pCO2, pO2, pH, electrolytes, lactate, glucose, packed cell volume (PCV), and total plasma protein concentration. Milk composition, ruminal VFA, and pH of faeces and urine were measured. SARA was associated with decreased (P < 0.05) minimum ruminal, faecal and urinary pH. Daily times and areas of ruminal pH below 5.8, and 5.6 were increased to levels representative for SARA. Significant differences were detected in milk composition and ruminal VFAs. Blood calcium concentration was decreased (P < 0.05), and pCO2 tended to be increased (P = 0.10). Significant differences were not detected in other parameters. SARA challenge was associated with changes in faecal and urinary pH, blood calcium concentration and pCO2. These may be helpful as indicators of SARA. However changes were small, and diurnal variations were present. None of these parameters are able to stand alone as indicators of SARA.

Effects of dietary roughage and sulfur in diets containing corn dried distillers grains with solubles on hydrogen sulfide production and fermentation by rumen microbes in vitro.

PubMed

Binversie, E Y; Ruiz-Moreno, M; Carpenter, A J; Heins, B J; Crawford, G I; DiCostanzo, A; Stern, M D

2016-09-01

Dried distillers grains with solubles (DDGS) have been used in production animal diets; however, overuse of DDGS can cause toxic concentrations of ruminal hydrogen sulfide gas (HS), resulting in polioencephalomalacia, a deleterious brain disease. Because HS gas requires an acidic rumen environment and diet can influence ruminal pH, it has been postulated that dietary manipulation could help mitigate HS production. The objective of this study was to assess the effect of dietary roughage and sulfur concentrations on HS production and rumen fermentation. In Exp. 1, 7 dual-flow continuous culture fermenters were used in 4 consecutive 9-d periods consisting of 6 d of adaptation followed by 3 d of sampling. At the conclusion of each 9-d continuous culture period, adapted rumen fluid was used for inoculation of 24-h batch culture incubations for Exp. 2. For both experiments, 6 dietary treatments were formulated to consist of 0.3%, 0.4%, or 0.5% dietary sulfur (LS, MS, and HS, respectively) and 3% or 9% dietary roughage (LR and MR, respectively), using grass hay as the roughage source. A corn-based diet without DDGS was used as a control diet. Headspace gas was sampled to determine HS production and concentration. In Exp. 1, greater dietary roughage had no effect ( = 0.14) on HS production but did create a less acidic environment because of an increase ( < 0.01) in the in vitro pH. In Exp. 2, an increase in dietary sulfur caused an increase ( = 0.04) in ruminal HS production, but there was no direct effect ( = 0.25) of dietary roughage on HS production. Greater dietary roughage resulted in a less ( = 0.01) acidic final batch culture pH but a lower ( < 0.01) total VFA concentration. Further investigation is needed to determine a more effective way to mitigate ruminal HS production using dietary manipulation, which could include greater inclusion of dietary roughage or the use of different roughage sources.

Comparison of feed intake, digestion and rumen function among domestic ruminant species grazing in upland vegetation communities.

PubMed

Ferreira, L M M; Hervás, G; Belenguer, A; Celaya, R; Rodrigues, M A M; García, U; Frutos, P; Osoro, K

2017-10-01

This study aimed to compare feed intake, digestion, rumen fermentation parameters and bacterial community of 5 beef cows, 12 crossed ewes and 12 goats grazing together in spring-early summer on heather-gorse vegetation communities with an adjacent area of improved pasture. Organic matter intake (OMI) and digestibility (OMD) were estimated using alkane markers. Ruminal fluid samples were collected for measuring fermentation parameters, and studying the bacterial community using terminal restriction fragment length polymorphism (T-RFLP). Spot samples of urine were taken to determine purine derivative (PD) and creatinine concentrations to estimate microbial protein synthesis in the rumen. Herbaceous species were the main dietary component in all animal species. Cattle had higher (p < 0.05) daily OMI (g/kg LW 0.75 ) and OMD, whereas sheep and goats showed similar values. The highest ammonia concentration was observed in sheep. Total VFA, acetate and butyrate concentrations were not influenced by animal species, while propionate concentrations in goats were 1.8 times lower (p < 0.05) than in sheep. Acetate:propionate ratio was greater (p < 0.05) in goats, whereas cattle excreted more allantoin (p < 0.05). Estimated supply of microbial N was higher in cows (p < 0.01), whereas the efficiency of microbial protein synthesis was lower (p < 0.01) in this animal species. Hierarchical clustering analysis indicated a clear effect of animal species on rumen bacterial structure. Differences among animal species were also observed in the relative frequency of several T-RFs. Certain T-RFs compatible with Lachnospiraceae, Proteobacteria and Clostridiales species were not found in goats, while these animals showed high relative frequencies of some fragments compatible with the Ruminococcaceae family that were not detected in sheep and cattle. Results suggest a close relationship between animals' grazing behaviour and rumen bacterial structure and its function. Goats seem to show a greater specialization of their microbial populations to deal with the greater fibrous and tannin content of their diet. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Diurnal Dynamics of Gaseous and Dissolved Metabolites and Microbiota Composition in the Bovine Rumen

PubMed Central

van Lingen, Henk J.; Edwards, Joan E.; Vaidya, Jueeli D.; van Gastelen, Sanne; Saccenti, Edoardo; van den Bogert, Bartholomeus; Bannink, André; Smidt, Hauke; Plugge, Caroline M.; Dijkstra, Jan

2017-01-01

Diurnal patterns of ruminal fermentation metabolites and microbial communities are not commonly assessed when investigating variation in ruminal CH4 production. The aims of this study were to monitor diurnal patterns of: (i) gaseous and dissolved metabolite concentrations in the bovine rumen, (ii) H2 and CH4 emitted, and (iii) the rumen microbiota. Furthermore, the effect of dietary inclusion of linseed oil on these patterns was assessed. Four rumen cannulated multiparous cows were used in a cross-over design with two 17 days periods and two dietary treatments: a control diet and a linseed oil supplemented diet [40% maize silage, 30% grass silage, 30% concentrate on dry matter (DM) basis for both diets; fat contents of 33 vs. 56 g/kg of DM]. On day 11, rumen contents were sampled for 10 h after morning feeding to profile gaseous and dissolved metabolite concentrations and microbiota composition. H2 and CH4 emission (mass per unit of time) was measured in respiration chambers from day 13 to 17. A 100-fold increase in ruminal H2 partial pressure (contribution to the total pressure of rumen headspace gases) was observed at 0.5 h after feeding. This peak was followed by a decline to basal level. Qualitatively similar patterns after feeding were also observed for H2 and CH4 emission, ethanol and lactate concentrations, and propionate molar proportion, although the opposite pattern was seen for acetate molar proportion. Associated with these patterns, a temporal biphasic change in the microbial composition was observed as based on 16S ribosomal RNA with certain taxa specifically associated with each phase. Bacterial concentrations (log10 16S ribosomal RNA gene copies based) were affected by time, and were increased by linseed oil supplementation. Archaeal concentrations (log10 16S ribosomal RNA gene copies based) tended to be affected by time and were not affected by diet, despite linseed oil supplementation decreasing CH4 emission, tending to decrease the partial pressure of CH4, and tending to increase propionate molar proportion. Linseed oil supplementation affected microbiota composition, and was most associated with an uncultivated Bacteroidales taxon. In summary, our findings support the importance of diurnal dynamics for the understanding of VFA, H2, and CH4 production. PMID:28367142

An analysis of the uncertainty and bias in DCE-MRI measurements using the spoiled gradient-recalled echo pulse sequence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Subashi, Ergys; Choudhury, Kingshuk R.; Johnson, G. Allan, E-mail: gjohnson@duke.edu

2014-03-15

Purpose: The pharmacokinetic parameters derived from dynamic contrast-enhanced (DCE) MRI have been used in more than 100 phase I trials and investigator led studies. A comparison of the absolute values of these quantities requires an estimation of their respective probability distribution function (PDF). The statistical variation of the DCE-MRI measurement is analyzed by considering the fundamental sources of error in the MR signal intensity acquired with the spoiled gradient-echo (SPGR) pulse sequence. Methods: The variance in the SPGR signal intensity arises from quadrature detection and excitation flip angle inconsistency. The noise power was measured in 11 phantoms of contrast agentmore » concentration in the range [0–1] mM (in steps of 0.1 mM) and in onein vivo acquisition of a tumor-bearing mouse. The distribution of the flip angle was determined in a uniform 10 mM CuSO{sub 4} phantom using the spin echo double angle method. The PDF of a wide range of T1 values measured with the varying flip angle (VFA) technique was estimated through numerical simulations of the SPGR equation. The resultant uncertainty in contrast agent concentration was incorporated in the most common model of tracer exchange kinetics and the PDF of the derived pharmacokinetic parameters was studied numerically. Results: The VFA method is an unbiased technique for measuringT1 only in the absence of bias in excitation flip angle. The time-dependent concentration of the contrast agent measured in vivo is within the theoretically predicted uncertainty. The uncertainty in measuring K{sup trans} with SPGR pulse sequences is of the same order, but always higher than, the uncertainty in measuring the pre-injection longitudinal relaxation time (T1{sub 0}). The lowest achievable bias/uncertainty in estimating this parameter is approximately 20%–70% higher than the bias/uncertainty in the measurement of the pre-injection T1 map. The fractional volume parameters derived from the extended Tofts model were found to be extremely sensitive to the variance in signal intensity. The SNR of the pre-injection T1 map indicates the limiting precision with which K{sup trans} can be calculated. Conclusions: Current small-animal imaging systems and pulse sequences robust to motion artifacts have the capacity for reproducible quantitative acquisitions with DCE-MRI. In these circumstances, it is feasible to achieve a level of precision limited only by physiologic variability.« less

In vivo indices for predicting acidosis risk of grains in cattle: Comparison with in vitro methods.

PubMed

Lean, I J; Golder, H M; Black, J L; King, R; Rabiee, A R

2013-06-01

Our objective was to evaluate a near-infrared reflectance spectroscopy (NIRS) used in the feed industry to estimate the potential for grains to increase the risk of ruminal acidosis. The existing NIRS calibration was developed from in sacco and in vitro measures in cattle and grain chemical composition measurements. To evaluate the existing model, 20 cultivars of 5 grain types were fed to 40 Holstein heifers using a grain challenge protocol and changes in rumen VFA, ammonia, lactic acids, and pH that are associated with acidosis were measured. A method development study was performed to determine a grain feeding rate sufficient to induce non-life threatening but substantial ruminal changes during grain challenge. Feeding grain at a rate of 1.2% of BW met these criteria, lowering rumen pH (P = 0.01) and increasing valerate (P < 0.01) and propionate concentrations (P = 0.01). Valerate was the most discriminatory measure indicating ruminal change during challenge. Heifers were assigned using a row by column design in an in vivo study to 1 of 20 grain cultivars and were reassigned after a 9 d period (n = 4 cattle/treatment). The test grains were dry rolled oats (n = 3), wheat (n = 6), barley (n = 4), triticale (n = 4), and sorghum (n = 3) cultivars. Cattle were adapted to the test grain and had ad libitum access to grass silage 11 d before the challenge. Feed was withheld for 14 h before challenge feeding with 0.3 kg DM of silage followed by the respective test grain fed at 1.2% of BW. A rumen sample was taken by stomach tube 5, 65, 110, 155, and 200 min after grain consumption. The rumen is not homogenous and samples of rumen fluid obtained by stomach tube will differ from those gained by other methods. Rumen pH was measured immediately; individual VFA, ammonia, and D- and L-lactate concentrations were analyzed later. Rumen pH (P = 0.002) and all concentrations of fermentation products differed among grains (P = 0.001). A previously defined discriminant score calculated at 200 min after challenge was used to rank grains for acidosis risk. A significant correlation between the discriminant score and the NIRS ranking (r = 0.731, P = 0.003) demonstrated the potential for using NIRS calibrations for predicting acidosis risk of grains in cattle. The overall rankings of grains for acidosis risk were wheat > triticale > barley > oats > sorghum.

The effects of active dried and killed dried yeast on subacute ruminal acidosis, ruminal fermentation, and nutrient digestibility in beef heifers.

PubMed

Vyas, D; Uwizeye, A; Mohammed, R; Yang, W Z; Walker, N D; Beauchemin, K A

2014-02-01

The study addressed the importance of yeast (Saccharomyces cerevisiae) viability for reducing the incidence of subacute ruminal acidosis (SARA) and improving total tract nutrient digestibility in beef heifers. Six ruminally cannulated beef heifers (680 ± 50 kg BW) were used in a replicated 3 × 3 Latin square design and were fed a diet consisting of 40% barley silage, 10% chopped grass hay, and 50% barley grain-based concentrate (DM basis). Treatments were 1) no yeast (Control), 2) active dried yeast (ADY; 4 g providing 10(10) cfu/g; AB Vista, Marlborough, UK), and 3) killed dried yeast (KDY; 4 g autoclaved ADY). The treatments were directly dosed via the ruminal cannula daily at the time of feeding. The periods consisted of 2 wk of adaptation (d 1 to 14) and 7 d of measurements (d 15 to 21). Ruminal pH was continuously measured (d 15 to 21) using an indwelling system. Ruminal contents were sampled on d 15 and 17 at 0, 3, 6, 9, and 12 h after feeding. Total tract nutrient digestibility was measured using an external marker (YbCl3) from d 15 to 19. No treatment difference was observed for DMI (P = 0.86). Yeast supplementation (ADY and KDY) tended to increase total tract digestibility of starch (P = 0.07) whereas no effects were observed on digestibility of other nutrients. Both ADY and KDY elevated minimum (P < 0.01) and mean ruminal pH (P = 0.02) whereas no effects were observed on maximum pH (P = 0.12). Irrespective of its viability, yeast supplementation was effective in reducing time that ruminal pH was below 5.8 (P < 0.01) and 5.6 (P < 0.01). No treatment differences were observed for the ruminal VFA profile and lactate concentration. No treatment differences were observed on the relative population size of Streptococcus bovis, Fibrobacter succinogenes, and Megasphaera elsdenii (P > 0.10); however, the proportion of Ruminococcus flavefaciens in solid fraction of digesta was greater with KDY (P = 0.05). The study demonstrates the positive effects of yeast, irrespective of its viability, in reducing the severity of SARA. However, further studies are required to evaluate the importance of yeast viability for other dietary conditions, particularly when the risk of acidosis is high.

Amino acid and energy interrelationships in growing beef steers: I. The effect of level of feed intake on ruminal characteristics and intestinal amino acid flows.

PubMed

Ludden, P A; Kerley, M S

1997-09-01

Five cannulated Holstein steers (538 +/- 35 kg) were used in a 4 x 4 Latin square design experiment with extra observations to examine the influence of level of feed intake on postruminal flow and intestinal disappearance of N and amino acids (AA). Treatments consisted of a single diet fed at four levels of energy intake (1.5, 2.0, 2.5, and 3.0 times NEm requirement). The diet was formulated on a DM basis to contain 13.25% CP using cracked corn (56.1%), soybean hulls (18%), cottonseed hulls (15%), soybean oil (4.25%), and corn gluten meal (5.6%). Increasing feed intake linearly increased (P < .0001) the quantity of OM truly digested in the stomach but tended to decrease (P = .11) OM digestion as a percentage of intake. Level of feed intake had no effect (P > .10) on ruminal pH, NH3 N, or peptide concentration or on particulate and fluid passage rates. However, total VFA concentration increased linearly (P < .0001) and the acetate: propionate ratio decreased linearly (P < .0001) as feed intake increased. Flows of microbial and nonmicrobial N at the duodenum linearly increased (P < .002) with increasing intake but did not differ (P > .10) as a percentage of intake. Level of feed intake did not affect (P > .10) microbial efficiency, N disappearance from the small intestine, or total tract N digestibility. With the exception of tryptophan, flows of all individual AA increased linearly (P < .01) with increasing intake. As a percentage of duodenal flow, AA digestion in the small intestine did not differ (P > .10), leading to a linear increase (P < .10) in the net quantity of individual (with the exception of tryptophan) and total AA disappearing from the small intestine as feed intake increased. Likewise, the profile of AA (except tryptophan) disappearing from the small intestine was unaffected (P > .10) by level of feed intake. When compared with predicted requirements for a 227-kg growing beef steer, Arg, Met, His, and Lys were suggested to be the most limiting AA for growth when this diet is fed. We conclude that altering energy intake by restricting intake of a single diet has only minor effects on the profile of digestible AA or other nutrients presented to the animal.

Effects of dietary inclusion of sunflower soap stocks on nutrient digestibility, growth performance, and ruminal and blood metabolites of light fattening lambs.

PubMed

Blanco, C; Giráldez, F J; Prieto, N; Morán, L; Andrés, S; Benavides, J; Tejido, M L; Bodas, R

2014-09-01

Forty-four merino lambs (6 to 8 wk old; BW 15.6 ± 0.21 kg) were used to study the effect of adding different proportions of sunflower soap stock (SS) to pelleted total mixed ration (TMR) for fattening lambs on feed intake, animal growth and dressing percentage, ruminal fluid characteristics, and blood acid-base parameters. Lambs were assigned to 1 of 4 experimental groups (11 lambs per group), each randomly assigned to 1 dietary treatment: 00SS (0 g SS/kg TMR pellet), 15SS (15 g SS/kg TMR pellet), 30SS (30 g SS/kg TMR pellet), and 60SS (60 g SS/kg TMR pellet). Lambs were individually fed the corresponding diet ad libitum. On d 19 to 23, total feces were collected and sampled from 4 lambs per group. When lambs reached 27 kg BW, they were slaughtered. Dry matter intake, ADG, and length of fattening period were not affected by the dietary treatment (P > 0.10). Animals in the 30SS group tended to show the best G:F values (P < 0.10). Dressing percentage tended to linearly decrease as SS increased (P < 0.10). Animals in the 60SS groups showed the lowest DM and fiber digestibility values (P < 0.05). Total VFA contents in ruminal fluid were not affected (P > 0.10), but the propionate proportion linearly increased (P < 0.05), and the acetate to propionate ratio tended to decrease with SS supplementation. Increasing dietary content of SS linearly decreased the cold carcass weight (P < 0.05) but did not affect other measured carcass characteristics. Ruminal fluid pH tended to decrease (P < 0.10) and mucosa color decreased as SS increased in the TMR (P < 0.05). Blood pH and Na concentration increased (P < 0.05), whereas the anion gap, CO2 pressure, and K concentration linearly decreased (P < 0.05) as SS increased. Including more than 30 g SS/kg TMR in the diet for fattening lambs reduces DM and fiber digestibility without affecting feed intake and ADG. The acidotic rumen conditions that induced a darkening of rumen mucosa were counteracted by blood acid-base parameters. The optimum level of inclusion seems to be 30 g SS/kg TMR.

Long-term stability of thermophilic co-digestion submerged anaerobic membrane reactor encountering high organic loading rate, persistent propionate and detectable hydrogen in biogas.

PubMed

Qiao, Wei; Takayanagi, Kazuyuki; Niu, Qigui; Shofie, Mohammad; Li, Yu You

2013-12-01

The performance of thermophilic anaerobic co-digestion of coffee grounds and sludge using membrane reactor was investigated for 148 days, out of a total research duration of 263 days. The OLR was increased from 2.2 to 33.7 kg-COD/m(3)d and HRT was shortened from 70 to 7 days. A significant irreversible drop in pH confirmed the overload of reactor. Under a moderately high OLR of 23.6 kg-COD/m(3)d, and with HRT and influent total solids of 10 days and 150 g/L, respectively, the COD removal efficiency was 44.5%. Hydrogen in biogas was around 100-200 ppm, which resulted in the persistent propionate of 1.0-3.2g/L. The VFA consumed approximately 60% of the total alkalinity. NH4HCO3 was supplemented to maintain alkalinity. The stability of system relied on pH management under steady state. The 16SrDNA results showed that hydrogen-utilizing methanogens dominates the archaeal community. The propionate-oxidizing bacteria in bacterial community was insufficient. Copyright © 2013 Elsevier Ltd. All rights reserved.

Methane production, ruminal fermentation characteristics, nutrient digestibility, nitrogen excretion, and milk production of dairy cows fed conventional or brown midrib corn silage.

PubMed

Hassanat, F; Gervais, R; Benchaar, C

2017-04-01

The objective of this study was to examine the effect of replacing conventional corn silage (CCS) with brown midrib corn silage (BMCS) in dairy cow diets on enteric CH 4 emission, nutrient intake, digestibility, ruminal fermentation characteristics, milk production, and N excretion. Sixteen rumen-cannulated lactating cows used in a crossover design (35-d periods) were fed (ad libitum) a total mixed ration (forage:concentrate ratio = 65:35, dry matter basis) based (59% dry matter) on either CCS or BMCS. Dry matter intake and milk yield increased when cows were fed BMCS instead of CCS. Of the milk components, only milk fat content slightly decreased when cows were fed the BMCS-based diet compared with when fed the CCS-based diet (3.81 vs. 3.92%). Compared with CCS, feeding BMCS to cows increased yields of milk protein and milk fat. Ruminal pH, protozoa numbers, total VFA concentration, and molar proportions of acetate and propionate were similar between cows fed BMCS and those fed CCS. Daily enteric CH 4 emission (g/d) was unaffected by dietary treatments, but CH 4 production expressed as a proportion of gross energy intake or on milk yield basis was lower for cows fed the BMCS-based diet than for cows fed the CCS-based diet. A decline in manure N excretion and a shift in N excretion from urine to feces were observed when BMCS replaced CCS in the diet, suggesting reduced potential of manure N volatilization. Results from this study show that improving fiber quality of corn silage in dairy cow diets through using brown midrib trait cultivar can reduce enteric CH 4 emissions as well as potential emissions of NH 3 and N 2 O from manure. However, CH 4 emissions during manure storage may increase due to excretion of degradable OM when BMCS diet is fed, which merits further investigation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Pre-treatment of high oil and grease pet food industrial wastewaters using immobilized lipase hydrolyzation.

PubMed

Jeganathan, Jeganaesan; Bassi, Amarjeet; Nakhla, George

2006-09-01

Wastewaters generating from pet food industries contain high concentration of oil and grease (O&G), which is difficult to treat through conventional biological treatment systems. In this study, the hydrolysis of O&G originating from pet food industrial wastewater was evaluated. Candida rugosa lipase was immobilized in calcium alginate beads and applied in the hydrolysis experiment. Results showed that approximately 50% of the O&G was hydrolyzed due to the enzyme activity. A significant increment in COD and VFA production was also observed. The immobilized lipase activity was confirmed with p-nitrophenyl palmitate (pNPP) before and after O&G hydrolysis. During the 3-day experiment, approximately 65% of the beads were recovered and after the hydrolysis, approximately 70% of the enzyme activity remained in the beads. This study shows the potential of immobilized lipase as a pre-treatment step in biological treatment of pet food manufacturing wastewater.

Evaluation of Methane from Sisal Leaf Residue and Palash Leaf Litter

NASA Astrophysics Data System (ADS)

Arisutha, S.; Baredar, P.; Deshpande, D. M.; Suresh, S.

2014-12-01

The aim of this study is to evaluate methane production from sisal leaf residue and palash leaf litter mixed with different bulky materials such as vegetable market waste, hostel kitchen waste and digested biogas slurry in a laboratory scale anaerobic reactor. The mixture was prepared with 1:1 proportion. Maximum methane content of 320 ml/day was observed in the case of sisal leaf residue mixed with vegetable market waste as the feed. Methane content was minimum (47 ml/day), when palash leaf litter was used as feed. This was due to the increased content of lignin and polyphenol in the feedstock which were of complex structure and did not get degraded directly by microorganisms. Sisal leaf residue mixtures also showed highest content of volatile fatty acids (VFAs) as compared to palash leaf litter mixtures. It was observed that VFA concentration in the digester first increased, reached maximum (when pH was minimum) and then decreased.

Waste activated sludge hydrolysis and acidification: A comparison between sodium hydroxide and steel slag addition.

PubMed

Zhang, Ying; Zhang, Chaojie; Zhang, Xuan; Feng, Leiyu; Li, Yongmei; Zhou, Qi

2016-10-01

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA (volatile fatty acid) in a shorter time can be achieved at pH10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supernatant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most phosphorus was released and captured by steel slag simultaneously in steel slag addition scenarios. These results suggest that steel slag can be used as a substitute for NaOH in sludge alkaline treatment. Copyright © 2016. Published by Elsevier B.V.

Removal and recovery of inhibitory volatile fatty acids from mixed acid fermentations by conventional electrodialysis.

PubMed

Jones, Rhys Jon; Massanet-Nicolau, Jaime; Guwy, Alan; Premier, Giuliano C; Dinsdale, Richard M; Reilly, Matthew

2015-08-01

Hydrogen production during dark fermentation is inhibited by the co-production of volatile fatty acids (VFAs) such as acetic and n-butyric acid. In this study, the effectiveness of conventional electrodialysis (CED) in reducing VFA concentrations in model solutions and hydrogen fermentation broths is evaluated. This is the first time CED has been reported to remove VFAs from hydrogen fermentation broths. During 60 min of operation CED removed up to 99% of VFAs from model solutions, sucrose-fed and grass-fed hydrogen fermentation broths, containing up to 1200 mg l(-1) each of acetic acid, propionic acid, i-butyric acid, n-butyric acid, i-valeric acid, and n-valeric acid. CED's ability to remove VFAs from hydrogen fermentation broths suggests that this technology is capable of improving hydrogen yields from dark fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Unravelling the active microbial community in a thermophilic anaerobic digester-microbial electrolysis cell coupled system under different conditions.

PubMed

Cerrillo, Míriam; Viñas, Marc; Bonmatí, August

2017-03-01

Thermophilic anaerobic digestion (AD) of pig slurry coupled to a microbial electrolysis cell (MEC) with a recirculation loop was studied at lab-scale as a strategy to increase AD stability when submitted to organic and nitrogen overloads. The system performance was studied, with the recirculation loop both connected and disconnected, in terms of AD methane production, chemical oxygen demand removal (COD) and volatile fatty acid (VFA) concentrations. Furthermore, the microbial population was quantitatively and qualitatively assessed through DNA and RNA-based qPCR and high throughput sequencing (MiSeq), respectively to identify the RNA-based active microbial populations from the total DNA-based microbial community composition both in the AD and MEC reactors under different operational conditions. Suppression of the recirculation loop reduced the AD COD removal efficiency (from 40% to 22%) and the methane production (from 0.32 to 0.03 m 3  m -3  d -1 ). Restoring the recirculation loop led to a methane production of 0.55 m 3  m -3  d -1 concomitant with maximum MEC COD and ammonium removal efficiencies of 29% and 34%, respectively. Regarding microbial analysis, the composition of the AD and MEC anode populations differed from really active microorganisms. Desulfuromonadaceae was revealed as the most active family in the MEC (18%-19% of the RNA relative abundance), while hydrogenotrophic methanogens (Methanobacteriaceae) dominated the AD biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lactic acid fermentation from food waste with indigenous microbiota: Effects of pH, temperature and high OLR.

PubMed

Tang, Jialing; Wang, Xiaochang; Hu, Yisong; Zhang, Yongmei; Li, Yuyou

2016-06-01

The effects of pH, temperature and high organic loading rate (OLR) on lactic acid production from food waste without extra inoculum addition were investigated in this study. Using batch experiments, the results showed that although the hydrolysis rate increased with pH adjustment, the lactic acid concentration and productivity were highest at pH 6. High temperatures were suitable for solubilization but seriously restricted the acidification processes. The highest lactic acid yield (0.46g/g-TS) and productivity (278.1mg/Lh) were obtained at 37°C and pH 6. In addition, the lactic acid concentration gradually increased with the increase in OLR, and the semi-continuous reactor could be stably operated at an OLR of 18g-TS/Ld. However, system instability, low lactic acid yield and a decrease in VS removal were noticed at high OLRs (22g-TS/Ld). The concentrations of volatile fatty acids (VFAs) in the fermentation mixture were relatively low but slightly increased with OLR, and acetate was the predominant VFA component. Using high-throughput pyrosequencing, Lactobacillus from the raw food waste was found to selectively accumulate and become dominant in the semi-continuous reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Physical activity and body composition changes during military service.

PubMed

Mikkola, Ilona; Jokelainen, Jari J; Timonen, Markku J; Härkönen, Pirjo K; Saastamoinen, Eero; Laakso, Mauri A; Peitso, Ari J; Juuti, Anna-Kaisa; Keinänen-Kiukaanniemi, Sirkka M; Mäkinen, Tiina M

2009-09-01

To examine how body composition changes in different body mass index (BMI) categories among young Finnish men during military service, which is associated with marked changes in diet and physical activity. In addition, this study examined how reported previous physical activity affected the body composition changes. Altogether 1003 men (19 yr) were followed throughout their military service (6-12 months). Height, weight, BMI, waist circumference, and waist-to-hip ratio (WHR) were recorded. Previous physical activity was assessed at the beginning of the service by a questionnaire. Body composition was measured by bioelectrical impedance assessments (BIA) at the beginning and at the end of the service. The measured parameters were fat mass (FM), fat percentage (fat %), fat-free mass (FFM), visceral fat area (VFA), lean body mass (LBM), and skeletal muscle mass (SMM). On average, military training decreased weight by 0.7%, FM by 9.7%, fat % by 6.6%, and VFA by 43.4%. FFM increased by 1.3%, LBM by 1.2%, and SMM by 1.7%. The group of underweight and normal-weight men gained weight, FM, and FFM, whereas overweight and obese men lost weight and FM and gained FFM. FM was most reduced in the groups of overweight (20.8%) and obese (24.9%) men. The amount of VFA was reduced in all BMI groups (38%-44%). Among overweight men who reported being inactive previous to the military service, more beneficial changes in body composition were observed compared with those who reported being physically active. The lifestyle changes associated with military service markedly reduce fat tissue and increase the amount of lean tissue. These beneficial changes are prominent among previously inactive subjects with high BMI.

Reduction of visceral fat by liraglutide is associated with ameliorations of hepatic steatosis, albuminuria, and micro-inflammation in type 2 diabetic patients with insulin treatment: a randomized control trial.

PubMed

Bouchi, Ryotaro; Nakano, Yujiro; Fukuda, Tatsuya; Takeuchi, Takato; Murakami, Masanori; Minami, Isao; Izumiyama, Hajime; Hashimoto, Koshi; Yoshimoto, Takanobu; Ogawa, Yoshihiro

2017-03-31

Liraglutide, an analogue of human glucagon-like peptide 1, reduces cardiovascular events in patients with type 2 diabetes; however, it has still been unknown by which mechanisms liraglutide could reduce cardiovascular events. Type 2 diabetic patients with insulin treatment were enrolled in this randomized, open-label, comparative study. Participants were randomly assigned to liraglutide plus insulin (liraglutide group) and insulin treatment (control group) at 1:1 allocation. Primary endpoint was the change in viscera fat are (VFA, cm 2 ) at 24 weeks. Liver attenuation index (LAI) measured by abdominal computed tomography, urinary albumin-to-creatinine ratio (ACR, mg/g), and C-reactive protein (CRP) levels, skeletal muscle index (SMI), and quality of life (QOL) related to diabetes treatment were also determined. Seventeen patients (8; liraglutide group, 9; control group, mean age 59 ± 13 years; 53% female) completed this study. Liraglutide treatment significantly reduced VFA at 24 weeks; whereas, SFA was unchanged. ACR, LAI, and CRP levels were significantly reduced by liraglutide at 24 weeks and there was no difference in SMI between the two groups. Changes in VFA from baseline to 24 weeks were significantly associated with those in LAI, albuminuria, and HbA1c. Liraglutide treatment significantly improved QOL scores associated with anxiety and dissatisfaction with treatment and satisfaction with treatment. No severe adverse events were observed in both groups. Our data suggest that liraglutide could reduce visceral adiposity in parallel with attenuation of hepatic fat accumulation, albuminuria and micro-inflammation and improve QOL related to diabetes care in insulin-treated patients with type 2 diabetes.

Effect of dietary roughage level on chewing activity, ruminal pH, and saliva secretion in lactating Holstein cows.

PubMed

Jiang, F G; Lin, X Y; Yan, Z G; Hu, Z Y; Liu, G M; Sun, Y D; Liu, X W; Wang, Z H

2017-04-01

Increasing dietary roughage level is a commonly used strategy to prevent subacute ruminal acidosis. We hypothesized that high-roughage diets could promote chewing activity, saliva secretion, and hence more alkaline to buffer rumen pH. To verify the hypothesis, 12 multiparous Holstein cows in mid lactation were randomly allocated to 4 treatments in a triplicated 4 × 4 Latin square experiment with one cow in each treatment surgically fitted with a ruminal cannula. Treatments were diets containing 40, 50, 60, or 70% of roughage on a DM basis. Increasing dietary roughage level decreased DM, CP, OM, starch, and NE L intake, increased ADF intake, and decreased milk yield linearly. Intake of NDF was quite stable across treatments and ranged from 7.8 to 8.1 kg/d per cow. Daily eating time increased linearly with increased roughage level. The increase in eating time was due to increased eating time per meal but not number of meals per day, which was stable and ranged from 8.3 to 8.5 meals per day across treatments. Increasing dietary roughage level had no effect on ruminating time (min/d), the number of ruminating periods (rumination periods per d), and chewing time per ruminating period (min/ruminating period). Ruminating time per kilogram of NDF intake and total chewing time per kilogram of ADF intake were similar across treatments (57.4 and 183.8 min/kg, respectively). Increasing dietary roughage level linearly increased daily total chewing time; linearly elevated the mean, maximum, and minimum ruminal pH; and linearly decreased total VFA concentration and molar proportion of propionate in ruminal fluid. Saliva secretion during eating was increased, the secretion during rumination was unaffected, but the secretion during resting tended to decrease with increased dietary roughage level. As a result, total saliva secretion was not affected by treatments. In conclusion, the results of the present study did not support the concept that high-roughage diets elevated ruminal pH through increased salivary recycling of buffering substrates. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Grass competition may benefit high density peach orchards

USDA-ARS?s Scientific Manuscript database

Previous research demonstrated that grass competition dwarfed and reduced the yield of individual peach trees [Prunus persica (L.) Batsch] grown in narrow vegetation free areas (VFA). In this report, the area-based yield of two peach cultivars, 'Redskin' and 'Jersey Dawn' on 'Lovell', was estimated...

Modelling mono-digestion of grass silage in a 2-stage CSTR anaerobic digester using ADM1.

PubMed

Thamsiriroj, T; Murphy, J D

2011-01-01

This paper examines 174 days of experimental data and modelling of mono-digestion of grass silage in a two stage wet process with recirculation of liquor; the two vessels have an effective volume of 312 L each. The organic loading rate is initiated at 0.5 kg VS m(-3) d(-1) (first 74 days) and subsequently increased to 1 kg VS m(-3) d(-1). The experimental data was used to generate a mathematical model (ADM1) which was calibrated over the first 74 days of operation. Good accuracy with experimental data was found for the subsequent 100 days. Results of the model would suggest starting the process without recirculation and thus building up the solids content of the liquor. As the level of VFA increases, recirculation should be employed to control VFA. Recirculation also controls solids content and pH. Methane production was estimated at 88% of maximum theoretical production. Copyright © 2010 Elsevier Ltd. All rights reserved.

A clustering-based graph Laplacian framework for value function approximation in reinforcement learning.

PubMed

Xu, Xin; Huang, Zhenhua; Graves, Daniel; Pedrycz, Witold

2014-12-01

In order to deal with the sequential decision problems with large or continuous state spaces, feature representation and function approximation have been a major research topic in reinforcement learning (RL). In this paper, a clustering-based graph Laplacian framework is presented for feature representation and value function approximation (VFA) in RL. By making use of clustering-based techniques, that is, K-means clustering or fuzzy C-means clustering, a graph Laplacian is constructed by subsampling in Markov decision processes (MDPs) with continuous state spaces. The basis functions for VFA can be automatically generated from spectral analysis of the graph Laplacian. The clustering-based graph Laplacian is integrated with a class of approximation policy iteration algorithms called representation policy iteration (RPI) for RL in MDPs with continuous state spaces. Simulation and experimental results show that, compared with previous RPI methods, the proposed approach needs fewer sample points to compute an efficient set of basis functions and the learning control performance can be improved for a variety of parameter settings.

Removal of volatile fatty acids and ammonia recovery from unstable anaerobic digesters with a microbial electrolysis cell.

PubMed

Cerrillo, Míriam; Viñas, Marc; Bonmatí, August

2016-11-01

Continuous assays with a microbial electrolysis cell (MEC) fed with digested pig slurry were performed to evaluate its stability and robustness to malfunction periods of an anaerobic digestion (AD) reactor and its feasibility as a strategy to recover ammonia. When performing punctual pulses of volatile fatty acids (VFA) in the anode compartment of the MEC, simulating a malfunction of the AD process, an increase in the current density was produced (up to 14 times, reaching values of 3500mAm(-2)) as a result of the added chemical oxygen demand (COD), especially when acetate was used. Furthermore, ammonium diffusion from the anode to the cathode compartment was enhanced and the removal efficiency achieved up to 60% during daily basis VFA pulses. An AD-MEC combined system has proven to be a robust and stable configuration to obtain a high quality effluent, with a lower organic and ammonium content. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bioconversion of volatile fatty acids derived from waste activated sludge into lipids by Cryptococcus curvatus.

PubMed

Liu, Jia; Liu, Jia-Nan; Yuan, Ming; Shen, Zi-Heng; Peng, Kai-Ming; Lu, Li-Jun; Huang, Xiang-Feng

2016-07-01

Pure volatile fatty acid (VFA) solution derived from waste activated sludge (WAS) was used to produce microbial lipids as culture medium in this study, which aimed to realize the resource recovery of WAS and provide low-cost feedstock for biodiesel production simultaneously. Cryptococcus curvatus was selected among three oleaginous yeast to produce lipids with VFAs derived from WAS. In batch cultivation, lipid contents increased from 10.2% to 16.8% when carbon to nitrogen ratio increased from about 3.5 to 165 after removal of ammonia nitrogen by struvite precipitation. The lipid content further increased to 39.6% and the biomass increased from 1.56g/L to 4.53g/L after cultivation for five cycles using sequencing batch culture (SBC) strategy. The lipids produced from WAS-derived VFA solution contained nearly 50% of monounsaturated fatty acids, including palmitic acid, heptadecanoic acid, ginkgolic acid, stearic acid, oleic acid, and linoleic acid, which showed the adequacy of biodiesel production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of crude-oil components and microorganisms that cause souring under anaerobic conditions.

PubMed

Hasegawa, R; Toyama, K; Miyanaga, K; Tanji, Y

2014-02-01

Oil souring has important implications with respect to energy resources. Understanding the physiology of the microorganisms that play a role and the biological mechanisms are both important for the maintenance of infrastructure and mitigation of corrosion processes. The objective of this study was to identify crude-oil components and microorganisms in oil-field water that contribute to crude-oil souring. To identify the crude-oil components and microorganisms that are responsible for anaerobic souring in oil reservoirs, biological conversion of crude-oil components under anaerobic conditions was investigated. Microorganisms in oil field water in Akita, Japan degraded alkanes and aromatics to volatile fatty acids (VFAs) under anaerobic conditions, and fermenting bacteria such as Fusibacter sp. were involved in VFA production. Aromatics such as toluene and ethylbenzene were degraded by sulfate-reducing bacteria (Desulfotignum sp.) via the fumarate-addition pathway and not only degradation of VFA but also degradation of aromatics by sulfate-reducing bacteria was the cause of souring. Naphthenic acid and 2,4-xylenol were not converted.

Anaerobic hydrolysis and acidification of organic substrates: determination of anaerobic hydrolytic potential.

PubMed

Rajagopal, Rajinikanth; Béline, Fabrice

2011-05-01

This study aimed to develop a biochemical-test mainly to evaluate the hydrolytic-potential of different substrates and to apply this test to characterize various organic substrates. Outcome of this study can be used for optimization of the WWTPs through enhancement of N/P removal or anaerobic digestion. Out of four series of batch experiments, the first two tests were conducted to determine the optimal operating conditions (test duration, inoculum-ratio etc.) for the hydrolytic-potential test using secondary and synthetically-prepared sludges. Based on the results (generation of CODs, pH and VFA), test duration was fixed between 6 and 7d allowing to attain maximum hydrolysis and to avoid methanogenesis. Effect of inoculum-ratios on acid fermentation of sludge was not significantly noticed. Using this methodology, third and fourth tests were performed to characterize various organic substrates namely secondary, pre-treated sludge, pig and two different cattle slurries. VFA production was shown to be substantially dependent on substrates types. Copyright © 2011 Elsevier Ltd. All rights reserved.

Polyhydroxyalkanoate synthesis by mixed microbial consortia cultured on fermented dairy manure: Effect of aeration on process rates/yields and the associated microbial ecology.

PubMed

Coats, Erik R; Watson, Benjamin S; Brinkman, Cynthia K

2016-12-01

Polyhydroxyalkanoates (PHAs) are biodegradable polymers that can substitute for petroleum-based plastics in a variety of applications. One avenue to commercial PHA production involves coupling waste-based synthesis with the use of mixed microbial consortia (MMC). In this regard, production requires maximizing the enrichment of a MMC capable of feast-famine PHA synthesis, with the metabolic response induced through imposition of aerobic-dynamic feeding (ADF) conditions. However, the concept of PHA production in complex matrices remains unrefined; process operational improvements are needed, along with an enhanced understanding of the MMC. Research presented herein investigated the effect of aeration on feast-famine PHA synthesis, with four independent aeration state systems studied; MMC were fed volatile fatty acid (VFA)-rich fermented dairy manure. Regardless of the aeration state, all MMC exhibited a feast-famine response based on observed carbon cycling. Moreover, there was no statistical difference in PHA synthesis rates, with q PHA ranging from 0.10 to 0.19 CmmolPHA gVSS -1 min -1 ; VFA uptake rates exhibited similar statistical indifferences. PHA production assessments on the enriched MMC resulted in maximum intracellular concentrations ranging from 22.5 to 90.7% (mgPHA mgVSS -1 ); at maximum concentration, the mean hydroxyvalerate mol content was 73 ± 0.6%. While a typical feast-famine dissolved oxygen (DO) pattern was observed at maximum aeration, less resolution was observed at decreasing aeration rates, suggesting that DO may not be an optimal process monitoring parameter. At lower aeration states, nitrogen cycling patterns, supported by molecular investigations targeting AOBs and NOBs, indicate that NO 2 and NO 3 sustained feast-famine PHA synthesis. Next-generation sequencing analysis of the respective MMC revealed numerous and diverse genera exhibiting the potential to achieve PHA synthesis, suggesting functional redundancy embedded in the diverse MMC. Ultimately, results demonstrate that aeration can be controlled in waste-based ADF systems to sustain PHA production potential, while enriching for a diverse MMC that exhibits potential functional redundancy. Reduced aeration could also enhance cost competitiveness of waste-based PHA production, with potential further benefits associated with nitrogen treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial Mechanistic Insight into the Role of Inulin in Improving Maternal Health in a Pregnant Sow Model

PubMed Central

Zhou, Pan; Zhao, Yang; Zhang, Pan; Li, Yan; Gui, Taotao; Wang, Jun; Jin, Chao; Che, Lianqiang; Li, Jian; Lin, Yan; Xu, Shengyu; Feng, Bin; Fang, Zhengfeng; Wu, De

2017-01-01

General consumption of “western diet” characterized by high refined carbohydrates, fat and energy intake has resulted in a global obesity epidemics and related metabolic disturbance even for pregnant women. Pregnancy process is accompanied by substantial hormonal, metabolic and immunological changes during which gut microbiota is also remarkably remodeled. Dietary fiber has been demonstrated to have a striking role in shifting the microbial composition so as to improve host metabolism and health in non-pregnant individuals. The present study was conducted to investigate effects of adding a soluble dietary fiber inulin (0 or 1.5%) to low- or high- fat (0 or 5% fat addition) gestational diet on maternal and neonatal health and fecal microbial composition in a sow model. Results showed that inulin addition decreased the gestational body weight gain and fat accumulation induced by fat addition. Circulating concentrations of pro-inflammatory cytokine IL-6, adipokine leptin and chemerin were decreased by inulin supplementation. Inulin addition remarkably reduced the average BMI of newborn piglets and the within litter BMI distributions (%) ranging between 17 and 20 kg/m2, and increased the BMI distribution ranging between 14 and 17 kg/m2. 16S rRNA gene sequencing of the V3-V4 region showed that fecal microbial changes at different taxonomic levels triggered by inulin addition predisposed the pregnant sow to be thinner and lower inflammatory. Meanwhile, fecal microbial composition was also profoundly altered by gestation stage with distinct changes occurring at perinatal period. Most representative volatile fatty acid (VFA) producing-related genera changed dramatically when reaching the perinatal period and varied degrees of increases were detected with inulin addition. Fecal VFA concentrations failed to show any significant effect with dietary intervention, however, were markedly increased at perinatal period. Our findings indicate that positive microbial changes resulted by 1.5% soluble fiber inulin addition would possibly be the potential mechanisms under which maternal body weight, metabolic and inflammatory status and neonatal BMI were improved. Besides, distinct changes of microbial community at perinatal period indicated the mother sow is undergoing a catabolic state with increased energy loss and inflammation response at that period compared with other stages of gestation. PMID:29204137

Monensin and a blend of castor oil and cashew nut shell liquid used in a high-concentrate diet abruptly fed to Nellore cattle.

PubMed

Zotti, C A; Silva, A P; Carvalho, R; Marino, C T; Rodrigues, P H M; Silva, L F P; McAllister, T A; Leme, P R

2017-09-01

Monensin and functional oils (FO) were supplemented to a high-concentrate diet abruptly fed to 12 ruminally cannulated Zebu steers to study their effects on rumen fermentation, blood metabolites, and , , and relative population. A randomized complete block design with repeated measures over time within 2 experimental periods of 21 d each was used. Treatments were a control (CTR; with no additives), FO (included at 400 mg/kg), and monensin included at 30 mg/kg (M30) or 40 mg/kg (M40). All steers were fed the same high-concentrate basal diet, which consisted of 92.25% concentrate. The first 60 h after transition showed a treatment and hour interaction for ruminal propionate proportion ( = 0.028), and no change in acetate molar proportion ( = 0.633), rumen pH ( = 0.370), and time the rumen pH remained below 5.6 ( = 0.242) were observed. The acetate:propionate ratio decreased ( = 0.020) when monensin was fed in both concentrations (2.30 for the M30 treatment and 2.32 for the M40 treatment) compared with when the CTR was fed (2.85), without being different when the FO (2.71) treatment was fed. Only the M30 treatment did not show pH below 5.2 (P=0.047) over the 60 h after the abrupt transition. Within the entire period, DMI ( = 0.008) and mean ruminal pH ( = 0.040) as well as molar proportions of propionate ( = 0.034) and valerate ( = 0.031) had significant interactions between treatment and day. Total VFA concentration was greater ( = 0.017) for the M30 (117.36 m) and CTR treatments (115.77 m) compared with the M40 treatment (105.02 m), without being different for the FO treatment (111.55 m). Treatments did not change feed behavior parameters. Blood HCO ( = 0.006) and total carbon dioxide ( = 0.003) were greater for the M30 (27.8 and 29.3 mmol/L, respectively) and FO treatments (28.3 and 29.7 mmol/L, respectively) compared with the CTR treatment (25.7 and 26.9 mmol/L, respectively). ( < 0.0001) and ( < 0.0001) decreased their population throughout days, whereas ( = 0.026) increased its population. Independent of ciliated protozoa genera, the greatest ( < 0.0001) protozoa counts were observed for the CTR treatment (52.7 × 10/mL), intermediate for the FO treatment (35.3 x10/mL), and least for steers fed monensin in both concentrations (15 × 10/mL for the M30 treatment and 14 × 10/mL for the M40 treatment). Feed additives had different effects to reduce the subacute acidosis. The use of the FO and M40 treatments did not change most of the rumen fermentation variables, especially in the first week after abrupt transition, when the M30 treatment provided higher protection against acidosis.

Effects of diet energy concentration and an exogenous carbohydrase on growth performance of weanling pigs fed diets containing canola meal produced from high protein or conventional canola seeds.

PubMed

Pedersen, T F; Liu, Y; Stein, H H

2016-12-01

The objectives were to determine effects of diet NE and an exogenous carbohydrase on growth performance and physiological parameters of weanling pigs fed a corn-soybean meal (SBM) diet or diets containing high protein canola meal (CM-HP) or conventional canola meal (CM-CV). A total of 492 pigs (initial BW: 9.15 ± 0.06 kg) were used in a randomized complete block design with 12 dietary treatments and 9 pens per treatment. A control diet based on corn and SBM and 4 diets containing 20% or 30% CM-HP or 20% or 30% CM-CV were formulated to a similar NE by adjusting inclusion of choice white grease. Four additional diets also contained 20% or 30% CM-HP or 20% or 30% CM-CV, but no additional choice white grease, and NE in these diets, therefore, was less than in the control diet. The control diet and the diets containing 30% CM-HP or CM-CV without increased choice white grease were also formulated with inclusion of an exogenous carbohydrase. Pigs were fed experimental diets for 22 d and 1 pig per pen was sacrificed at the conclusion of the experiment. Results indicated that compared with the control diet, there was no impact of canola meal on final BW, ADG, ADFI, or G:F, but pigs fed CM-CV had greater ( < 0.05) final BW, ADG, and ADFI than pigs fed CM-HP, and pigs fed diets with reduced NE had greater ( < 0.05) ADG and ADFI than pigs fed diets with constant NE. Only minor effects of CM-HP or CM-CV on intestinal weight, gut fill, digesta pH, cecal VFA concentrations, and serum concentrations of urea N, total N, or albumin were observed, but the weight of the thyroid gland increased ( < 0.05) as the concentration of dietary canola meal increased. Serum concentrations of IgG were reduced if canola meal was included in the diets without the carbohydrase, but that was not the case if the carbohydrase was included in the diet (interaction, ( < 0.05). In conclusion, up to 30% CM-HP or CM-CV in diets fed to weanling pigs from 2 wk postweaning did not impact growth performance compared with pigs fed a corn-SBM diet, and NE in diets containing canola meal does not have to be similar to that of corn-SBM diets. However, inclusion of CM-CV containing 4.43 µmol/g glucosinolates in the diets resulted in improved growth performance compared with inclusion of CM-HP containing 12.60 µmol/g glucosinolates.

Biophysical Interactions Control the Size and Abundance of Large Phytoplankton Chains at the Ushant Tidal Front

PubMed Central

Landeira, José M.; Ferron, Bruno; Lunven, Michel; Morin, Pascal; Marié, Louis; Sourisseau, Marc

2014-01-01

Phytoplankton blooms are usually dominated by chain-forming diatom species that can alter food pathways from primary producers to predators by reducing the interactions between intermediate trophic levels. The food-web modifications are determined by the length of the chains; however, the estimation is biased because traditional sampling strategies damage the chains and, therefore, change the phytoplankton size structure. Sedimentological studies around oceanic fronts have shown high concentrations of giant diatom mats (>1 cm in length), suggesting that the size of diatom chains is underestimated in the pelagic realm. Here, we investigate the variability in size and abundance of phytoplankton chains at the Ushant tidal front (NW France) using the Video Fluorescence Analyzer (VFA), a novel and non-invasive system. CTD and Scanfish profiling characterized a strong temperature and chlorophyll front, separating mixed coastal waters from the oceanic-stratified domain. In order to elucidate spring-neap variations in the front, vertical microstructure profiler was used to estimate the turbulence and vertical nitrate flux. Key findings were: (1) the VFA system recorded large diatom chains up to 10.7 mm in length; (2) chains were mainly distributed in the frontal region, with maximum values above the pycnocline in coincidence with the maximum chlorophyll; (3) the diapycnal fluxes of nitrate enabled the maintenance of the bloom in the frontal area throughout the spring-neap tidal cycle; (4) from spring to neap tide the chains length was significantly reduced; (5) during neap tide, the less intense vertical diffusion of nutrients, as well as the lower turbulence around the chains, intensified nutrient-depleted conditions and, thus, very large chains became disadvantageous. To explain this pattern, we suggest that size plasticity is an important ecological trait driving phytoplankton species competition. Although this plasticity behavior is well known from experiments in the laboratory, it has never been reported from observations in the field. PMID:24587384

Digestion of rice straw and oil palm fronds by microflora from rumen and termite bacteria, in vitro.

PubMed

Ramin, M; Alimon, A R; Panandam, J M; Sijam, K; Javanmard, A; Abdullah, N

2008-02-15

The digestion and Volatile Fatty Acid (VFA) production from rice straw and oil palm fronds by cellulolytic bacteria isolated from the termite Coptotermes curvignathus were investigated. The bacteria were Acinetobacter strain Raminalimon, Enterobacter aerogenes strain Razmin C, Enterobacter cloacae strain Razmin B, Bacillus cereus strain Razmin A and Chryseobacterium kwangyangense strain Cb. Acinetobacter strain Raminalimon is an aerobic bacterium, while the other species are facultative anaerobes. There were significant differences (p<0.05) among the bacteria for Dry Matter (DM) lost and acetic acid production from rice straw and Acinetobacter strain Raminalimon showed the highest activity. The facultative bacteria C. kwangyangense strain Cb (cfu mL(-1) 231 x 10(-6), OD: 0.5), E. cloacae (cfu mL(-1) 68 x 10(-7), OD: 0.5) and E. aerogenes (cfu mL(-1) 33 x 10(-7), OD: 0.5) were used for digestion study with the rumen fluid microflora. The in vitro gas production technique was applied for the comparative study and the parameters measured were pH, gas (volume), dry matter lost, acetic acid, propionic acid and butyric acid concentrations. pH was not significantly (p<0.05) different among the five treatments. The bacterium C. kwangyangense strain Cb showed the highest activity (p<0.05) for DM lost, acetic acid, propionic acid and butyric acid production from rice straw when compared to the other bacterial activities. There was no significance (p<0.05) difference between the three bacteria for the dry matter lost of oil palm fronds but the production of Volatile Fatty Acids (VFA) was significantly (p<0.05) high in the treatment which was inoculated with C. kwangyangense strain Cb. The Gen Bank NCBI/EMBL accession numbers for the bacterial strains are EU332791, EU305608, EU305609, EU294508 and EU169201.

Microbiological characterization and specific methanogenic activity of anaerobe sludges used in urban solid waste treatment.

PubMed

Lozano, Claudia Johanna Sandoval; Mendoza, Marisol Vergara; de Arango, Mariela Carreño; Monroy, Edgar Fernando Castillo

2009-02-01

This study presents the microbiological characterization of the anaerobic sludge used in a two-stage anaerobic reactor for the treatment of organic fraction of urban solid waste (OFUSW). This treatment is one alternative for reducing solid waste in landfills at the same time producing a biogas (CH(4) and CO(2)) and an effluent that can be used as biofertilizer. The system was inoculated with sludge from a wastewater treatment plant (WWTP) (Río Frío Plant in Bucaramanga-Colombia) and a methanogenic anaerobic digester for the treatment of pig manure (Mesa de los Santos in Santander). Bacterial populations were evaluated by counting groups related to oxygen sensitivity, while metabolic groups were determined by most probable number (MPN) technique. Specific methanogenic activity (SMA) for acetate, formate, methanol and ethanol substrates was also determined. In the acidogenic reactor (R1), volatile fatty acids (VFA) reached values of 25,000 mg L(-1) and a concentration of CO(2) of 90%. In this reactor, the fermentative population was predominant (10(5)-10(6)MPN mL(-1)). The acetogenic population was (10(5)MPN mL(-1)) and the sulphate-reducing population was (10(4)-10(5)MPN mL(-1)). In the methanogenic reactor (R2), levels of CH(4) (70%) were higher than CO(2) (25%), whereas the VFA values were lower than 4000 mg L(-1). Substrate competition between sulphate-reducing (10(4)-10(5)MPN mL(-1)) and methanogenic bacteria (10(5)MPN mL(-1)) was not detected. From the SMA results obtained, acetoclastic (2.39 g COD-CH(4)g(-1)VSS(-1)day(-1)) and hydrogenophilic (0.94 g COD-CH(4)g(-1)VSS(-1)day(-1)) transformations as possible metabolic pathways used by methanogenic bacteria is suggested from the SMA results obtained. Methanotrix sp., Methanosarcina sp., Methanoccocus sp. and Methanobacterium sp. were identified.

Similar PAH Fate in Anaerobic Digesters Inoculated with Three Microbial Communities Accumulating Either Volatile Fatty Acids or Methane

PubMed Central

Braun, Florence; Hamelin, Jérôme; Bonnafous, Anaïs; Delgenès, Nadine; Steyer, Jean-Philippe; Patureau, Dominique

2015-01-01

Urban sludge produced on wastewater treatment plants are often contaminated by organic pollutants such as polycyclic aromatic hydrocarbons (PAH). Their removal under methanogenic conditions was already reported, but the factors influencing this removal remain unclear. Here, we determined the influence of microbial communities on PAH removal under controlled physico-chemical conditions. Twelve mesophilic anaerobic digesters were inoculated with three microbial communities extracted from ecosystems with contrasting pollution histories: a PAH contaminated soil, a PCB contaminated sediment and a low contaminated anaerobic sludge. These anaerobic digesters were operated during 100 days in continuous mode. A sterilised activated sludge, spiked with 13 PAH at concentrations usually encountered in full-scale wastewater treatment plants, was used as substrate. The dry matter and volatile solid degradation, the biogas production rate and composition, the volatile fatty acids (VFA) production and the PAH removals were monitored. Bacterial and archaeal communities were compared in abundance (qPCR), in community structure (SSCP fingerprinting) and in dominant microbial species (454-pyrosequencing). The bioreactors inoculated with the community extracted from low contaminated anaerobic sludge showed the greater methane production. The PAH removals ranged from 10 % to 30 %, respectively, for high and low molecular weight PAH, whatever the inoculums tested, and were highly correlated with the dry matter and volatile solid removals. The microbial community structure and diversity differed with the inoculum source; this difference was maintained after the 100 days of digestion. However, the PAH removal was not correlated to these diverse structures and diversities. We hence obtained three functional stable consortia with two contrasted metabolic activities, and three different pictures of microbial diversity, but similar PAH and matter removals. These results confirm that PAH removal depends on the molecule type and on the solid matter removal. But, as PAH elimination is similar whether the solid substrate is degraded into VFA or into methane, it seems that the fermentative communities are responsible for their elimination. PMID:25874750

Similar PAH fate in anaerobic digesters inoculated with three microbial communities accumulating either volatile fatty acids or methane.

PubMed

Braun, Florence; Hamelin, Jérôme; Bonnafous, Anaïs; Delgenès, Nadine; Steyer, Jean-Philippe; Patureau, Dominique

2015-01-01

Urban sludge produced on wastewater treatment plants are often contaminated by organic pollutants such as polycyclic aromatic hydrocarbons (PAH). Their removal under methanogenic conditions was already reported, but the factors influencing this removal remain unclear. Here, we determined the influence of microbial communities on PAH removal under controlled physico-chemical conditions. Twelve mesophilic anaerobic digesters were inoculated with three microbial communities extracted from ecosystems with contrasting pollution histories: a PAH contaminated soil, a PCB contaminated sediment and a low contaminated anaerobic sludge. These anaerobic digesters were operated during 100 days in continuous mode. A sterilised activated sludge, spiked with 13 PAH at concentrations usually encountered in full-scale wastewater treatment plants, was used as substrate. The dry matter and volatile solid degradation, the biogas production rate and composition, the volatile fatty acids (VFA) production and the PAH removals were monitored. Bacterial and archaeal communities were compared in abundance (qPCR), in community structure (SSCP fingerprinting) and in dominant microbial species (454-pyrosequencing). The bioreactors inoculated with the community extracted from low contaminated anaerobic sludge showed the greater methane production. The PAH removals ranged from 10% to 30%, respectively, for high and low molecular weight PAH, whatever the inoculums tested, and were highly correlated with the dry matter and volatile solid removals. The microbial community structure and diversity differed with the inoculum source; this difference was maintained after the 100 days of digestion. However, the PAH removal was not correlated to these diverse structures and diversities. We hence obtained three functional stable consortia with two contrasted metabolic activities, and three different pictures of microbial diversity, but similar PAH and matter removals. These results confirm that PAH removal depends on the molecule type and on the solid matter removal. But, as PAH elimination is similar whether the solid substrate is degraded into VFA or into methane, it seems that the fermentative communities are responsible for their elimination.

Butyrate: A dietary inhibitor of histone deacetylases and an epigenetic regulator

USDA-ARS?s Scientific Manuscript database

The short-chain fatty acids (SCFAs) acetate, propionate and butyrate, also known as volatile fatty acids (VFA), are produced in the gastrointestinal tract by microbial fermentation. Consumption of dietary fibers has been shown to have positive metabolic health effects, such as increasing satiety, an...

Development of a 4.75-mm (No. 4) NMS mixture : research project capsule.

DOT National Transportation Integrated Search

2017-08-01

The objective of this project is to develop a 4.75-mm NMAS asphalt mixture for Louisiana roads, which will involve establishing target criteria for aggregate gradations, volumetric properties (e.g., air voids, VMA, VFA, and dust-to-binder ratio) and ...

Effects of ionophores and antibiotics on in vitro hydrogen sulfide production, dry matter disappearance, and total gas production in cultures with a steam-flaked corn-based substrate with or without added sulfur.

PubMed

Quinn, M J; May, M L; Hales, K E; DiLorenzo, N; Leibovich, J; Smith, D R; Galyean, M L

2009-05-01

Effects of 3 ionophores and 2 antibiotics on in vitro H(2)S production, IVDMD, total gas production, and VFA profile with or without added S were examined. In Exp. 1, ruminal fluid from 2 ruminally cannulated steers fed a steam-flaked corn-based diet (75% concentrate) without ionophore and antibiotics for 28 d before collection was used to inoculate in vitro cultures. Treatments were control (no ionophore or antibiotic), 3 ionophores (lasalocid sodium and monensin sodium at 5 mg/L or laidlomycin propionate at 1.65 mg/L), and 2 antibiotics (chlortetracycline hydrochloride at 5 mg/L and tylosin tartarate at 1.25 mg/L). Cultures also had 0 or 1.75 mg of S/L (from sodium sulfate). No S x ionophore-antibiotic treatment interactions were noted (P > 0.53) for IVDMD, total gas production, and H(2)S production. Hydrogen sulfide (mumol/g of fermentable DM) was increased (P < 0.001), and total gas production tended (P = 0.09) to be increased with additional S; however, IVDMD was not affected by added S (P = 0.90). Production of H(2)S was not affected by ionophores or antibiotics (P > 0.18). On average, IVDMD (P = 0.05) was greater for ionophores than for antibiotics, whereas total gas production was less for ionophores than for control (P < 0.001) and antibiotics (P < 0.001). Molar proportions of acetate (P < 0.01) and acetate:propionate (P < 0.01) were decreased and propionate was increased (P < 0.001) in ionophore treatments when no S was added, but when S was added there were no differences (P > 0.20) in acetate, propionate, or acetate:propionate between ionophores and control (S x treatment interaction, P = 0.03). In Exp. 2, the effects of ionophore-antibiotic combinations with added S were examined using the same procedures as in Exp. 1. Treatments were control, monensin plus tylosin (MT), and lasalocid plus chlortetracycline (LCTC), with concentrations of the ionophores and antibiotics as in Exp. 1. No differences were observed among treatments for H(2)S production (P > 0.55). Treatments MT and LCTC tended (P = 0.06) to increase IVDMD and decreased (P = 0.02) gas production vs. control. Proportion of acetate (P = 0.01) and acetate:propionate (P < 0.01) were decreased and propionate increased (P = 0.01) for both MT and LCTC compared with control. These data suggest that when S is approximately 0.42% of substrate DM, the 3 ionophores and 2 antibiotics we evaluated did not affect production of H(2)S gas in an in vitro rumen culture system.

Made to Measure: College Leaders Come Together to Strengthen Institutional Accountability

ERIC Educational Resources Information Center

Boerner, Heather

2015-01-01

Since the American Association of Community Colleges (AACC) launched the Voluntary Framework of Accountability (VFA) in 2011, accountability measures have sprung up in just about every corner of higher education. There is the Integrated Postsecondary Education Data System (IPEDS), the National Governors Association's Complete to Compete program,…

Using electromagnetic induction technology to predict volatile fatty acid, source area differences

USDA-ARS?s Scientific Manuscript database

Subsurface sampling techniques have been adapted to measure manure accumulation on feedlot surface. Objectives of this study were to determine if sensor data could be used to predict differences in volatile fatty acids (VFA) and other volatiles produced on the feedlot surface three days following a...

Nutrient-induced modulation of gene expression and cellular functions: modeling epigenetic regulation in bovine cells

USDA-ARS?s Scientific Manuscript database

Volatile fatty acids (VFA), especially butyrate, participate in metabolism both as nutrients and as regulators of histone deacetylation. The major biochemical change that occurs in cells treated with butyrate is the global hyperacetylation of histones. One paradigmatic example of the nutrient-epige...

Perturbation dynamics of the rumen microbiota in response to exogenous butyrate

USDA-ARS?s Scientific Manuscript database

The capacity of the rumen microbiota to produce volatile fatty acids (VFA) has important implications in animal well-being and production. We investigated temporal changes of the rumen microbiota in response to butyrate infusion using pyrosequencing of the 16S rRNA gene. Phyla were identified in ...

Dietary Habits Prone to Lifestyle-Related Disease

ERIC Educational Resources Information Center

Nagai, M.; Uyama, O.; Kaji, H.

2013-01-01

Objective: To evaluate relations among dietary habits, bone mineral density (BMD), visceral fat area (VFA), and arterial stiffness and recommend better dietary habits. Methods: One hundred and six men and 381 women (aged 18-84) received a health checkup and answered questionnaires, with subsequent measurements of BMD (speed of sound), VFA…

Role of rumen butyrate in regulation of nitrogen utilization and urea nitrogen kinetics in growing sheep.

PubMed

Agarwal, U; Hu, Q; Baldwin, R L; Bequette, B J

2015-05-01

Butyrate, a major rumen VFA, has been indirectly linked to enhancement of urea recycling on the basis of increased expression of urea transporter in the rumen epithelia of steers fed a rumen butyrate-enhancing diet. Two studies were conducted to quantify the effect of elevated rumen butyrate concentrations on N balance, urea kinetics and rumen epithelial proliferation. Wether sheep (n= 4), fitted with a rumen cannula, were fed a pelleted ration (∼165 g CP/kg DM, 10.3 MJ ME/kg DM) at 1.8 × ME requirement. In Exp. 1, sheep were infused intraruminally with either an electrolyte buffer solution (Con-Buf) or butyrate dissolved in the buffer solution (But-Buf) during 8-d periods in a balanced crossover design. In Exp. 2, sheep were infused intraruminally with either sodium acetate (Na-Ac) or sodium butyrate (Na-But) for 9 d. All solutions were adjusted to pH 6.8 and 8.0 in Exp. 1 and 2, respectively, and VFA were infused at 10% of ME intake. [15N2] urea was continuously infused intravenously for the last 5 d of each period, and total urine and feces were collected. In Exp. 1, 2H5-phenylalanine was continuously infused intravenously over the last 12 h, after which a biopsy from the rumen papillae was taken for measurement of fractional protein synthesis rate (FSR). Butyrate infusion treatments increased (P = 0.1 in Exp. 1; P < 0.05 in Exp. 2) the proportion of rumen butyrate, and acetate infusion increased (P < 0.05) rumen acetate. All animals were in positive N balance (4.2 g N/d in Exp. 1; 7.0 g N/d in Exp. 2), but no difference in N retention was observed between treatments. In Exp. 2, urea entry (synthesis) rate was reduced ( < 0.05) by Na-But compared with the Na-Ac control. In Exp. 1, although But-Buf infusion increased the FSR of rumen papillae (35.3% ± 1.08%/d vs. 28.7% ± 1.08%/d; P < 0.05), urea kinetics were not altered by But-Buf compared with Con-Buf. These studies are the first to directly assess the role of butyrate in urea recycling and its effects on rumen papillae protein turnover in growing lambs. Under the feeding conditions used and the rate of continuous butyrate infusion into the rumen in the present studies, butyrate does not affect overall N retention in growing sheep. However, butyrate may play a role in the redistribution of urea N fluxes in the overall scheme of N metabolism.

Impact of co-landfill proportion of bottom ash and municipal solid waste composition on the leachate characteristics during the acidogenesis phase.

PubMed

He, Pin-Jing; Pu, Hong-Xia; Shao, Li-Ming; Zhang, Hua

2017-11-01

Incineration has become an important municipal solid waste (MSW) treatment strategy, and generates a large amount of bottom ash (BA). Although some BA is reused, much BA and pretreatment residues from BA recycling are disposed in landfill. When BA and MSW are co-landfilled together, acid neutralization capacity and alkaline earth metal dissolution of BA, as well as different components of MSW may change environmental conditions within the landfill, so the degradation of organic matter and the physical and chemical properties of leachate would be affected. In this study, the effect of co-landfilled BA and MSW on the leachate characteristics during the hydrolysis and acidogenesis phase was studied using different BA/MSW ratios and MSW compositions. The results showed that the co-landfill system increased leachate pH, electric conductivity and alkalinity. For MSW with a high content of degradable components, the release and degradation of total organic carbon (TOC) and volatile fatty acids (VFA) from MSW were promoted when the BA ratio by wet weight was less than 50%, and the biodegradability of leachate was improved. When the BA ratio exceeded 50%, the degradation of organic matters was inhibited. For MSW with low content of degradable components, when the proportion of BA was less than 20%, the release and degradation of TOC and VFA from MSW were promoted and alkalinity increased. When the BA ratio exceeded 20%, the degradation of organic matters was inhibited. The 50% BA ratio could improve the bio-treatability of leachate indicated by the leachate pH and C/N ratio. However, BA inhibited the release of nitrogen (TN and NH 4 + -N) at all BA ratios and MSW compositions. At the same time, the addition of BA increased the risk of leachate collection system clogging due to the dissolution and re-precipitation of alkaline earth metals contained in BA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of feeding lauric acid or coconut oil on ruminal protozoa numbers, fermentation pattern, digestion, omasal nutrient flow, and milk production in dairy cows.

PubMed

Faciola, A P; Broderick, G A

2014-01-01

The objectives of this study were to evaluate the feeding of coconut oil (CO), in which lauric acid (La) comprises about 50% of the fatty acid composition, as a practical rumen protozoa (RP) suppressing agent, to assess whether the source of La affects ruminal fermentation and animal performance and to test whether suppressing RP improves N utilization, nutrient digestion, nutrient flow at the omasal canal, and milk production. Fifteen multiparous Holstein cows (3 fitted with ruminal cannulas) and 15 primiparous Holstein cows (3 fitted with ruminal cannulas) were used in a replicated 3×3 Latin square experiment with 14d of adaptation and 14d of sample collection. Diets were fed as total mixed ration and contained (dry matter basis) 10% corn silage, 50% alfalfa silage, and 40% concentrate. The control diet contained 3% (dry matter basis) calcium soaps of palm oil fatty acids (Megalac, Church & Dwight Co. Inc., Princeton, NJ) as a ruminally inert fat source and had no added La or CO. Diets with La and CO were formulated to contain equal amounts of La (1.3%, dry matter basis). Dry matter intake was not affected by treatment. Both CO and La reduced RP numbers by about 40%. Lauric acid reduced yield of milk and milk components; however, CO did not affect yield of milk and yields of milk components. Both La and CO caused small reductions in total VFA concentration; CO increased molar proportion of ruminal propionate, reduced ruminal ammonia and branched-chain volatile fatty acids, suggesting reduced protein degradation, and reduced milk urea N and blood urea N concentrations, suggesting improved protein efficiency. Lauric acid reduced total-tract apparent digestibility of neutral detergent fiber and acid detergent fiber as well as ruminal apparent digestibility of neutral detergent fiber and acid detergent fiber as measured at the omasal canal; however, CO did not alter fiber digestion. Microbial protein flow at the omasal canal, as well as the flow of N fractions at the omasal canal, did not differ among treatments. Results from this experiment have confirmed that dietary La is not a practical agent for suppressing RP population in dairy cows, mainly because of its negative effects on fiber digestion and ruminal fermentation. Intake of CO appeared to reduce ruminal and improve protein efficiency, but did not improve milk production, milk composition, or increase microbial outflow from the rumen. Based on the results of this study, a 40% reduction of RP population is not sufficient to improve N utilization in dairy cows. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The definition of acidosis in dairy herds predominantly fed on pasture and concentrates.

PubMed

Bramley, E; Lean, I J; Fulkerson, W J; Stevenson, M A; Rabiee, A R; Costa, N D

2008-01-01

This cross-sectional survey examined the prevalence of ruminal acidosis and the effects of acidosis on the production of dairy cattle. Eight fresh cows, 3 primiparous and 5 multiparous (< 100 d in milk), were selected randomly from each of 100 dairy herds in 5 regions of Australia. Rumen fluid was obtained from each cow by rumenocentesis and a stomach tube, and samples were tested for pH. Stomach tube rumen fluid samples were analyzed for volatile fatty acid, ammonia, and D-lactate concentrations. On the basis of the results of all assays, cows were categorized into 3 distinct categories (categories 1, 2, and 3) by cluster analysis. The percentages of cattle in categories 1, 2, and 3 were 10.2, 29.9, and 59.9%, respectively. Mean rumen pH for categories 1, 2, and 3 were 5.74 +/- 0.47, 6.18 +/- 0.44, and 6.33 +/- 0.43, respectively. Biochemically, categories 1, 2, and 3 were characterized, respectively, as follows: mean total VFA concentration (mM), 100.74 +/- 23.22, 94.79 +/- 18.13, and 62.81 +/- 15.65; mean ammonia concentration (mM), 2.46 +/- 2.02, 7.79 +/- 3.75, and 3.64 +/- 2.03; and mean D-lactate concentration (mM), 0.34 +/- 0.86, 0.28 +/- 0.97, and 0.12 +/- 0.51. Category 1 cows had higher propionate, valerate, isovalerate, and caproate concentrations and were of lower parity than cows in other categories. Cows in category 1 had higher milk production but lower milk fat content than category 2 cows. Herds were assigned to 1 of 3 groups according to the numbers of cows assigned to each category. Herds with > or = 3 of the 8 cows in category 1 were classified as acidotic. Herds with > or = 3 of the 8 cows in category 2 were classified as having suboptimal rumen function, and herds with > or = 3 of the 8 cows in category 3 were classified as normal. Herds that had 3 or more of the 8 cows in category 1 (acidotic herds) had diets with higher energy and nonfiber carbohydrate contents and a lower neutral detergent fiber content than herds with a high prevalence of category 2 or 3 cows. The lack of significance of a herd effect in the statistical models developed suggests that the categories were robust across production systems, in which diets varied from all pasture to total mixed rations. A point prevalence of 10% (95% credible interval, 8 to 12%) of cows with an acidotic profile indicates a high risk for acidosis in the cattle sampled. The higher nonfiber carbohydrate and lower neutral detergent fiber contents of diets for herds with a high prevalence of category 1 cows (acidotic herds) indicates that there may be opportunities to reduce the risk of acidosis by dietary manipulation.

Effect of ammoniacal nitrogen on one-stage and two-stage anaerobic digestion of food waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ariunbaatar, Javkhlan, E-mail: jaka@unicas.it; UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft; Scotto Di Perta, Ester

Highlights: • Almost 100% of the biomethane potential of food waste was recovered during AD in a two-stage CSTR. • Recirculation of the liquid fraction of the digestate provided the necessary buffer in the AD reactors. • A higher OLR (0.9 gVS/L·d) led to higher accumulation of TAN, which caused more toxicity. • A two-stage reactor is more sensitive to elevated concentrations of ammonia. • The IC{sub 50} of TAN for the AD of food waste amounts to 3.8 g/L. - Abstract: This research compares the operation of one-stage and two-stage anaerobic continuously stirred tank reactor (CSTR) systems fed semi-continuouslymore » with food waste. The main purpose was to investigate the effects of ammoniacal nitrogen on the anaerobic digestion process. The two-stage system gave more reliable operation compared to one-stage due to: (i) a better pH self-adjusting capacity; (ii) a higher resistance to organic loading shocks; and (iii) a higher conversion rate of organic substrate to biomethane. Also a small amount of biohydrogen was detected from the first stage of the two-stage reactor making this system attractive for biohythane production. As the digestate contains ammoniacal nitrogen, re-circulating it provided the necessary alkalinity in the systems, thus preventing an eventual failure by volatile fatty acids (VFA) accumulation. However, re-circulation also resulted in an ammonium accumulation, yielding a lower biomethane production. Based on the batch experimental results the 50% inhibitory concentration of total ammoniacal nitrogen on the methanogenic activities was calculated as 3.8 g/L, corresponding to 146 mg/L free ammonia for the inoculum used for this research. The two-stage system was affected by the inhibition more than the one-stage system, as it requires less alkalinity and the physically separated methanogens are more sensitive to inhibitory factors, such as ammonium and propionic acid.« less

Effects of Bacillus subtilis natto and Different Components in Culture on Rumen Fermentation and Rumen Functional Bacteria In Vitro.

PubMed

Sun, Peng; Li, Jinan; Bu, Dengpan; Nan, Xuemei; Du, Hong

2016-05-01

This study was to investigate the effects of live or autoclaved Bacillus subtilis natto, their fermented products and media on rumen fermentation and rumen functional bacteria in vitro. Rumen fluid from three multiparous lactating Holstein cows was combined and transferred into serum bottles after diluted. Fifteen serum bottles were divided into five treatments, which were designed as following: CTR (the fermentation of 0.5 g TMR and ruminal fluids from dairy cows), LBS (CTR plus a minimum of 10(11) cfu live Bacillus subtilis natto), ABS (CTR plus a minimum of 10(11) cfu autoclaved Bacillus subtilis natto), BSC (CTR plus 1 ml Bacillus subtilis natto fermentation products without bacteria), and BSM (CTR plus 1 ml liquid fermentation medium). When separated from the culture, live Bacillus subtilis natto individually increased the concentrations of ammonia-N (P < 0.01), MCP production (P < 0.01), and tended to elevate total VFA (P = 0.07), but decreased the ratio of acetate and propionate (P < 0.01). Autoclaved Bacillus subtilis natto has the similar function with the live bacteria except for the ratio of acetate and propionate. Except B. fibrisolvens, live or autoclaved Bacillus subtilis natto did not influence or decreased the 16S rRNA gene quantification of the detected bacteria. BSC and BSM altered the relative expression of certain functional bacteria in the rumen. These results indicated that it was Bacillus subtilis natto thalli that played the important role in promoting rumen fermentation when applied as a probiotic in dairy ration.

Influence of Continuous Flow Microwave Pre-Treatment on Anaerobic Digestion of Secondary Thickened Sludge for Sustainable Energy Recovery in Sewage Treatment Plant

NASA Astrophysics Data System (ADS)

Hephzibah, D.; Kumaran, P.; Saifuddin, N. M.

2016-03-01

This work elucidates the effects of pre-treatment of secondary thickened sludge (STS) for enhancement of biogas production that has great potential to generate energy for the utilization of the sewage treatment plant (STP) itself. Microwave pre-treatment has been adopted for this study. Experiment works have been designed and conducted to examine the effectiveness of continuous flow microwave pre-treatment on the solubility of STS, digestibility of STS and biogas production at a power level of 80 W for 5, 10 and 15 minutes. A few characteristics of the sewage sludge were monitored daily to identify the effect of pre-treatment on the sludge. The soluble chemical oxygen demand (SCOD)/total chemical oxygen demand (TCOD) ratio increased by 0.1, 1.0 and 1.8%, while the volatile fatty acids (VFA) concentration of the pre-treated sludge improved by 4.4, 5.1, 5.9% at the irradiation time of 5, 10 and 15 minutes, respectively at a microwave power level of 80 W. Besides that, the digestate also indicates that the pre-treated sludge undergoes efficient VS removal and TCOD removal after anaerobic digestion compared to the untreated sludge. Moreover, the biogas quantity increased by an average of 19.2, 24.1 and 32.2% in 5, 10 and 15 minutes irradiation time respectively compared to the untreated sludge. The additional quantity of biogas generated has shown a great potential for sustainable energy generation that can be utilized internally by the STP.

Modification of ruminal fermentation and methane production by adding legumes containing condensed tannins to an orchardgrass diet in continuous culture systems

USDA-ARS?s Scientific Manuscript database

Condensed tannins (CT) can alter ruminal fermentation and enteric methane (CH4) production in ruminants; however, research is lacking on how increased CT levels affect nutrient digestibility, volatile fatty acid (VFA) production, bacterial protein synthesis, fatty acid (FA) profiles, protozoal popul...

Host-rumen microbe interactions may be leveraged to improve the productivity of dairy cows

USDA-ARS?s Scientific Manuscript database

The cattle rumen serves as a digestive bioreactor for the dairy cow, yet our knowledge of the microbial contents, ecology, and host selection within the rumen is only precursory. This is despite the knowledge that the volatile fatty acids (VFA) and microbial crude protein (MCP) produced by rumen mic...

Redox mediators modify end product distribution in biomass fermentations by mixed ruminal microbes in vitro

USDA-ARS?s Scientific Manuscript database

The fermentation system of mixed ruminal bacteria is capable of generating large amounts of short-chain volatile fatty acids (VFA) via the carboxylate platform in vitro. These VFAs are subject to elongation to larger, more energy-dense products through reverse beta-oxidation. This study examined the...

Enteric methane production and ruminal fermentation of forage brassica diets fed in continuous culture

USDA-ARS?s Scientific Manuscript database

The aim of the current study was to determine nutrient digestibility, VFA production, N metabolism, and CH4 production of canola (Brassica napus L.), rapeseed (B. napus L.), turnip (B. rapa L.), and annual ryegrass (Lolium multiflorum Lam.) fed with orchardgrass (Dactylis glomerata L.) in continuous...

In Situ Biogeochemical Treatment Demonstration: Lessons Learned from ESTCP Project ER 201124

DTIC Science & Technology

2015-12-09

vegetable oil fermentation to volatile fatty acids (VFA) also likely reduced the pH and this change could have reduced the FeS reactivity. 2.3.5...Initially about 6.5 ● Vegetable oil fermentation to VFAs ● Lower FeSx reactivity Need to balance iron and sulfur! 55 Critical Factors

Effect of summer annuals on ruminal fermentation and methane output in continuous culture

USDA-ARS?s Scientific Manuscript database

Summer annuals (SA) provide forage during the summer “forage slump”, yet research on ruminal fermentation and CH4 output of SA is lacking. A 4-unit, dual-flow continuous culture fermentor system was used to assess nutrient digestibility, VFA production, bacterial protein synthesis, and CH4 output of...

Production of poly(hydroxybutyrate-hydroxyvalerate) from waste organics by the two-stage process: focus on the intermediate volatile fatty acids.

PubMed

Shen, Liang; Hu, Hongyou; Ji, Hongfang; Cai, Jiyuan; He, Ning; Li, Qingbiao; Wang, Yuanpeng

2014-08-01

The two-stage process, coupling volatile fatty acids (VFAs) fermentation and poly(hydroxybutyrate-hydroxyvalerate) (P(HB/HV)) biosynthesis, was investigated for five waste organic materials. The overall conversion efficiencies were glycerol>starch>molasses>waste sludge>protein, meanwhile the maximum P(HB/HV) (1.674 g/L) was obtained from waste starch. Altering the waste type brought more effects on VFAs composition other than the yield in the first stage, which in turn greatly changed the yield in the second stage. Further study showed that even-number carbon VFAs (or odd-number ones) had a good positive linear relationship with P(HB/HV) content of HB (or HV). Additionally, VFA producing microbiota was analyzed by pyrosequencing methods for five wastes, which indicated that specific species (e.g., Lactobacillus for protein; Ethanoligenens for starch; Ruminococcus and Limnobacter for glycerol) were dominant in the community for VFAs production. Potential competition among acidogenic bacteria specially involved to produce some VFA was proposed as well. Copyright © 2014 Elsevier Ltd. All rights reserved.

Use of submerged anaerobic membrane bioreactor (SAMBR) containing powdered activated carbon (PAC) for the treatment of textile effluents.

PubMed

Baêta, B E L; Ramos, R L; Lima, D R S; Aquino, S F

2012-01-01

This work investigated the use of submerged anaerobic membrane bioreactors (SAMBRs) in the presence and absence of powdered activated carbon (PAC) for the treatment of genuine textile wastewater. The reactors were operated at 35 °C with an HRT of 24 h and the textile effluent was diluted (1:10) with nutrient solution containing yeast extract as the source of the redox mediation riboflavin. The results showed that although both SAMBRs exhibited an excellent performance, the presence of PAC inside SAMBR-1 enhanced reactor stability and removal efficiency of chemical oxygen demand (COD), volatile fatty acids (VFA), turbidity and color. The median removal efficiencies of COD and color in SAMBR-1 were, 90 and 94% respectively; whereas for SAMBR-2 (without PAC) these values were 79 and 86%, In addition, the median values of turbidity and VFA were 8 NTU and 8 mg/L for SAMBR-1 and 14 NTU and 26 mg/L for SAMBR-2, indicating that the presence of PAC inside SAMBR-1 led to the production of an anaerobic effluent of high quality regarding such parameters.

Hydrolysis-acidogenesis of food waste in solid-liquid-separating continuous stirred tank reactor (SLS-CSTR) for volatile organic acid production.

PubMed

Karthikeyan, Obulisamy Parthiba; Selvam, Ammaiyappan; Wong, Jonathan W C

2016-01-01

The use of conventional continuous stirred tank reactor (CSTR) can affect the methane (CH4) recovery in a two-stage anaerobic digestion of food waste (FW) due to carbon short circuiting in the hydrolysis-acidogenesis (Hy-Aci) stage. In this research, we have designed and tested a solid-liquid-separating CSTR (SLS-CSTR) for effective Hy-Aci of FW. The working conditions were pH 6 and 9 (SLS-CSTR-1 and -2, respectively); temperature-37°C; agitation-300rpm; and organic loading rate (OLR)-2gVSL(-1)day(-1). The volatile fatty acids (VFA), enzyme activities and bacterial population (by qPCR) were determined as test parameters. Results showed that the Hy-Aci of FW at pH 9 produced ∼35% excess VFA as compared to that at pH 6, with acetic and butyric acids as major precursors, which correlated with the high enzyme activities and low lactic acid bacteria. The design provided efficient solid-liquid separation there by improved the organic acid yields from FW. Copyright © 2015 Elsevier Ltd. All rights reserved.

Converting the organic fraction of solid waste from the city of Abu Dhabi to valuable products via dark fermentation--Economic and energy assessment.

PubMed

Bonk, Fabian; Bastidas-Oyanedel, Juan-Rodrigo; Schmidt, Jens Ejbye

2015-06-01

Landfilling the organic fraction of municipal solid waste (OFMSW) leads to greenhouse gas emissions and loss of valuable resources. Sustainable and cost efficient solutions need to be developed to solve this problem. This study evaluates the feasibility of using dark fermentation (DF) to convert the OFMSW to volatile fatty acids (VFAs), fertilizer and H2. The VFAs in the DF effluent can be used directly as substrate for subsequent bioprocesses or purified from the effluent for industrial use. DF of the OFMSW in Abu Dhabi will be economically sustainable once VFA purification can be accomplished on large scale for less than 15USD/m(3)(effluent). With a VFA minimum selling price of 330 USD/tCOD, DF provides a competitive carbon source to sugar. Furthermore, DF is likely to use less energy than conventional processes that produce VFAs, fertilizer and H2. This makes DF of OFMSW a promising waste treatment technology and biorefinery platform. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhancement of acidogenic fermentation for volatile fatty acid production from food waste: Effect of redox potential and inoculum.

PubMed

Yin, Jun; Yu, Xiaoqin; Zhang, Yeer; Shen, Dongsheng; Wang, Meizhen; Long, Yuyang; Chen, Ting

2016-09-01

The aim of this study was to explore the effects of redox potential (ORP) and inoculum on volatile fatty acids (VFAs) production from food waste by acidogenic fermentation. Four experimental conditions with two ORP levels were tested: limited aeration conditions with ORP level of -100 to -200mV inoculating anaerobic sludge (LA+AnS) or aerobic sludge (LA+AeS), and anaerobic conditions with ORP level of -200 to -300mV inoculating anaerobic sludge with 2-bromoethanosulfophate (AN+BES) and without BES (AN). The maximal VFA yield (0.79g COD/g VS) was attained in LA+AnS reactor due to enhanced hydrolysis of substrates, especially proteins (degradation efficiency 78.3%). A higher frequency of phylum Firmicutes under limited aeration conditions (42.2-48.2%) was observed than that under anaerobic conditions (21.1%). The microbial community was more diverse in LA+AnS reactors than LA+AeS. We conclude that appropriate ORP level (from -100 to -200mV) and inoculum play essential roles in VFA production. Copyright © 2016 Elsevier Ltd. All rights reserved.