Pasture-based dairy producers in the US face costs, revenues and management challenges that differ from those associated with conventional dairy production systems. Three Grazing Merit indexes (GM$1, GM$2, and GM$3), parallel to the US Lifetime Net Merit (NM$) index, were constructed using economic ...
Parallels exist in the recent developments of dairy systems in the Northeast United States and New Zealand because of greater use of pasture grazing and feed supplements, respectively. Lessons can be learned from each system. However, major differences exist between the regions in the patterns of pasture production, the costs of supplementary feed, and milk prices. These differences affect the
D. G. McCall; D. A. Clark; L. J. Stachurski; J. W. Penno; A. M. Bryant; B. J. Ridler
Confinement and grazing-based dairy producers face many challenges, including rising cost of inputs (labor, fertilizer, energy, machinery), economic disadvantages relative to commodity feeds, potential negative environmental impacts, legislation restricting operations, and variable climatic conditio...
Grazed pasture, which is the cheapest source of nutrients for dairy cows, should form the basis of profitable and low-input animal production systems. Management of high-producing dairy cows at pasture is thus a major challenge in most countries. The objective of the present paper is to review the factors that can affect nutrient supply for grazing dairy cows in order to point out areas with scope for improvement on managing variations in nutrient supply to achieve high animal performance while maintaining efficient pasture utilisation per hectare (ha). Reviewing the range in animal requirements, intake capacity and pasture nutritive values shows that high-producing cows cannot satisfy their energy requirements from grazing alone and favourable to unfavourable situations for grazing dairy cows may be classified according to pasture quality and availability. Predictive models also enable calculation of supplementation levels required to meet energy requirements in all situations. Solutions to maintain acceptable level of production per cow and high output per ha are discussed. Strategies of concentrate supplementation and increasing use of legumes in mixed swards are the most promising. It is concluded that although high-producing cow cannot express their potential milk production at grazing, there is scope to improve animal performance at grazing given recent developments in our understanding of factors influencing forage intake and digestion of grazed forages. PMID:23031792
Peyraud, J L; Delagarde, R
This study investigated the effects of different strategies for feeding supplements to grazing dairy cows on the proportions of fatty acids in milk. Two hundred and sixteen cows were fed supplementary grain and forage according to one of 3 different strategies; (1) CONTROL: cows grazed perennial ryegrass pasture (14 kg dry matter/d) supplemented with milled barley grain fed in the milking parlour and pasture silage offered in the paddock; (2) Partial mixed ration 1 (PMR1): same pasture allotment and supplement as CONTROL strategy, but the supplements presented as a mixed ration after each milking in feedpad, and; (3) Partial mixed ration 2 (PMR2): same pasture allotment, supplemented with a mixed ration of milled barley grain, alfalfa hay, corn silage and crushed corn grain fed in a feedpad. Within each strategy, cows were assigned to receive either 6, 8, 10 or 12 kg dry matter supplement/cow per d. Milk fatty acid proportions from cows fed CONTROL and PMR1 strategies were similar and different from those fed PMR2, particularly at 10 to 12 kg dry matter supplement/cow per d. The reduction in milk fat yield and concentration in cows fed high amounts of supplement as CONTROL and PMR1 was coincident with 4 × increase in 10t-18:1 proportion. The composition of the partial mixed ration (PMR) and the amount offered affected milk fatty acid proportions and milk fat content, however, the method of supplementation did not. PMID:24560061
Akbaridoust, Ghazal; Plozza, Tim; Trenerry, Victor C; Wales, William J; Auldist, Martin J; Dunshea, Frank R; Ajlouni, Said
This paper explores the interaction of grazing pregnant dairy cattle (lactating and non-lactating) with contaminated pasture. Behavioural responses were divided into investigative and ingestive grazing events. Patches of sward were artificially contaminated with slurry (containing faeces and urine) and were used to test the behavioural interactions; faecal collection bags ensured no further contamination occurred throughout the two 1-week periods of
David L. Swain; Michael A. Friend; Robert W. Mayes; Lyn A. Wilson; Mike R. Hutchings
Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality® inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than during full-time winter housing. Furthermore, we expected improved welfare with an increase in daily summer grazing hours. In total, 41 herds have been visited once in the winter and once in the summer of 2010 to assess their welfare status with 17 different animal- and resource-based welfare measures. A panel of 20 experts on cattle welfare and husbandry evaluated the relative weight of the 17 welfare measures in a multidimensional assessment scheme. They estimated exact weights for a priori constituted severe compared with moderate scores of welfare impairment concerning each measure, as well as relevance of the measures in relation to each other. A welfare index (WI; possible range 0 to 5400) was calculated for each herd and season with a higher index indicating poorer welfare. The within-herd comparison of summer grazing v. winter housing considered all the 17 measures. The mean WI in summer was significantly lower (better) than in winter (mean 2926 v. 3330; paired t-test P = 0.0001) based on a better state of the integument, claw conformation and better access to water and food. Body condition and faeces consistence were worse in summer. Many daily grazing hours (range average above 3 to 9 h) turned out to be more beneficial than few daily grazing hours (range average above 9 to 21 h) for the welfare of the dairy herds. In conclusion, this study reports a positive within-herd effect of summer grazing on dairy cow welfare, where many daily grazing hours were more beneficial than few daily grazing hours. PMID:23244468
Burow, E; Rousing, T; Thomsen, P T; Otten, N D; Sørensen, J T
. Twenty-four grazing Holstein cows in mid and late lactation were randomly assigned to two treatment groups: control and cooled. The trial was performed at the Experimental Dairy Unit, Rafaela Agricultural Experimental Station (INTA), Argentina. The objective was to evaluate the effects of sprinkler and fan cooling before milkings on milk production and composition. The effects of the cooling system on rectal temperature and respiration rate were also evaluated. Cooled cows showed higher milk production (1.04 l cow-1 day-1). The concentration and yield of milk fat and protein increased in response to cooling treatment. The cooling system also reduced rectal temperature and respiration rate. No effects were observed on body condition. It was concluded that evaporative cooling, which is efficient for housed animals, is also appropriate to improve yields and animal well-being under grazing systems. These results are impressive since the cooling system was utilized only before milkings, in a system where environmental control is very difficult to achieve. This trial was performed during a mild summer. The results would probably be magnified during hotter weather.
Valtorta, Silvia E.; Gallardo, Miriam R.
This study analyzes the use and profitability of three distinct feeding systems; confinement feeding, traditional grazing, and management-intensive grazing from a randomly selected sample of northeastern dairy farms. The confinement feeding farms were significantly larger and produced more milk per cow, while the farms using management-intensive grazing incurred the lowest production costs. Both confinement feeding and management-intensive grazing generated significantly
Jonathan R. Winsten; Robert L. Parsons; Gregory D. Hanson
Grasslands act as sinks and sources of greenhouse gases (GHG) and are, in conjunction with livestock production systems, responsible for a large share of GHG emissions. Whereas ecosystem scale flux measurements (eddy covariance) are commonly used to investigate CO2 exchange (and is becoming state-of-the-art for other GHGs, too), GHG emissions from agricultural animals are usually investigated on the scale of individual animals. Therefore eddy covariance technique has to be tested for combined systems (i.e. grazed systems). Our project investigates the ability of field scale flux measurements to reliably quantify the contribution of grazing dairy cows to the net exchange of CO2 and CH4. To quantify the contribution of the animals to the net flux the position, movement, and grazing/rumination activity of each cow are recorded. In combination with a detailed footprint analysis of the eddy covariance fluxes, the animal related CO2 and CH4 emissions are derived and compared to standard emission values derived from respiration chambers. The aim of the project is to test the assumption whether field scale CO2 flux measurements adequately include the respiration of grazing cows and to identify potential errors in ecosystem Greenhouse gas budgets.
Felber, R.; Ammann, C.; Neftel, A.
Many cows have difficulty making the transition from pregnancy to lactation, as evidenced by the high incidence of disease that occurs in the weeks after calving. Changes in lying behavior can be used as an indicator of illness, yet no work to date has evaluated this relationship in dairy cows on pasture. The objectives of this study were to describe the lying behavior of grazing dairy cows during the first 3 wk after calving and determine the relationships between transition diseases and lying behavior. Our convenience sample included 227 multiparous and 47 primiparous Holstein cows from 6 commercial farms. Cows were recruited as they calved during the spring calving period. Electronic data loggers (Hobo Pendant G Acceleration, Onset Computer Corp., Pocasset, MA) recorded lying behavior at 1-min intervals. Diseases were recorded up to 21 d in milk, and cows were subsequently categorized into 3 health categories: (1) healthy, not lame and had no other signs of clinical (retained placenta, milk fever, metritis, mastitis) or subclinical (ketosis, hypocalcemia) postpartum diseases; (2) lame, identified as being clinically or severely lame with no other signs of clinical or subclinical postpartum disease; and (3) sick, diagnosed as having one or more clinical postpartum diseases (with or without a subclinical disease) but not lame. This last group was further divided into 2 groups: those that were diagnosed with a single clinical health event and those diagnosed with more than one clinical event. Lying behavior differed between primiparous and multiparous cows; primiparous cows divided their lying time into more bouts than did multiparous cows (9.7 ± 0.54 vs. 8.4 ± 0.26 bouts/d) and spent less time lying down than multiparous cows (7.5 ± 0.38 h/d vs. 8.5 ± 0.19 h/d). Lying behavior was also affected by illness; primiparous cows that developed more than one clinical disease, excluding lameness, spent more time lying, and tended to have longer lying bouts in the days following calving compared with healthy cows; multiparous severely lame cows spent more time lying down (1.7 h longer per day) compared with multiparous cows that were nonlame. Clinically lame cows had fewer lying bouts per day and these bouts were of longer duration than healthy nonlame cows. In summary, changes in lying behavior after calving were associated with postpartum health status in grazing dairy cows. PMID:25151885
Sepúlveda-Varas, P; Weary, D M; von Keyserlingk, M A G
Increasingly, the dairy industry in the eastern US is transitioning from total confinement dairy systems (TCD) toward pasture-based, management intensive grazing dairy (MiGD) systems. This transition is driven by the fact that MiGDs require substantially less operating capital and are more economically efficient than TCD systems. Consequently, the impact of this transition and shift in land-use practice on carbon dynamics may be considerable. Land-use in a Management intensive Grazing Dairy (MiGD) system is fundamentally different than conventional confinement dairies and conventional no-till pastures. The forage system involves rotational grazing at optimal digestibility, when the plants are immature (~20-days) and consequently protein-rich. MiGD cows spend >90% of their time in the field and deposit > 90% of their waste directly to the soil surface. Thus, little above ground plant residues are directly returned to the soil, but rather substantial C inputs derive from bovine manure. We sampled a MiGD-chronosequence of row-crop to MiGD conversion established in 2007 in eastern Georgia. All soils across the MiGD-chronosequence, all occur in relative (40 km) close proximity to one another, are deep, well-drained, fine and fine sandy loam Ultisols formed on Coastal Plain sediments. Prior to MiGD established, the soils were farmed for > 50 yrs using conventional tillage techniques. Our current sampling to 1m depths captures fields at 0, 2, 3, and 5 yrs since conversion. Total soil carbon (C) and the carbon concentration of the clay fraction increased following conversion, with the greatest increases occurring between 3 and 5 yrs since conversion. These C increases were limited to the upper 40cm of the soil, with minimal change occurring at depth. Characterization of the protein and ligand content of these soils via 13C NMR and chemolytic techniques as a function of soil particle density and size is in progress and will be presented along with estimates of carbon dioxide and methane fluxes across the MiGD chronosequence. Our broad goal is to quantify ruminal methane emissions and changes to soil C-stocks and stability associated with this land-use shift. Our preliminary data suggest such a land-use change will likely improve soil health and increase C-stocks. Balancing this against potential increases in methane emissions is a key knowledge gap for future southeastern U.S. C-cycling estimates.
Thompson, A.; Kramer, M. G.; Hill, N.; Machmuller, M. B.; Cyle, K.
Pasture biomass is a vital input for management of dairy systems in New Zealand. An accurate estimate of pasture biomass information is required for the calculation of feed budget, on which decisions are made for farm practices such as conservation, nitrogen use, rotational lengths and supplementary feeding leading to profitability and sustainable use of pasture resources. The traditional field based methods of measuring pasture biomass such as using rising plate metres (RPM) are largely inefficient in providing the timely information at the spatial extent and temporal frequency demanded by commercial environments. In recent times remote sensing has emerged as an alternative tool. In this paper we have examined the Normalised Difference Vegetation Index (NDVI) derived from medium resolution imagery of SPOT-4 and SPOT-5 satellite sensors to predict pasture biomass of intensively grazed dairy pastures. In the space and time domain analysis we have found a significant dependency of time over the season and no dependency of space across the scene at a given time for the relationship between NDVI and field based pasture biomass. We have established a positive correlation (81%) between the two variables in a pixel scale analysis. The application of the model on 2 selected farms over 3 images and aggregation of the predicted biomass to paddock scale has produced paddock average pasture biomass values with a coefficient of determination of 0.71 and a standard error of 260 kg DM ha-1 in the field observed range between 1500 and 3500 kg DM ha-1. This result indicates a high potential for operational use of remotely sensed data to predict pasture biomass of intensively grazed dairy pastures.
Edirisinghe, Asoka; Clark, Dave; Waugh, Deanne
Experiments were carried out on tropical grass pasture, in summer 2002, to find out possible mitigation options to reduce methane emission using different categories of grazing dairy cattle breeds. Methane emission was measured using the SF6 tracer technique. Experimental design was a block distribution in tim e, along four consecutive weeks, five days a week, at 12 -hour intervals, employing
Brazil Frighetto; M. A. Lima
Mixed livestock grazing can offer an alternative management system for rearing dairy replacement heifers (Bos taurus). A 2-yr study was conducted during 2009 (yr 1) and 2010 (yr 2) to determine the effects of co-grazing Holstein heifers under rotational stocking with Boer × Kiko goats on animal performance, pasture DM yield, and botanical composition. Each year, 24 heifers (134 ± 6 d of age and 147.4 ± 31.2 kg BW in yr 1; 166 ± 11 d of age and 168.0 ± 27.6 kg BW in yr 2) and 6 goats (2 yr old and 39.7 ± 16.2 kg BW in yr 1; 1 yr old and 33.7 ± 7.4 kg BW in yr 2) were divided into 6 paddocks with 4 heifers and 2 goats, where applicable, per group. Low endophyte-infected tall fescue (Festuca arundinacea Schreb.) and white clover (Trifolium repens L.) pastures were used to evaluate 2 grazing strategies (heifers grazed alone [HO] or heifers co-grazed with goats [HG]). In addition, 6 goats were assigned to 2 paddocks and grazed alone (GO) each year to estimate goat pasture forage intake and compare Haemonchus contortus infection to co-grazed goats. Forage samples were taken monthly to assess DM yield and botanical composition. Samples collected for botanical composition were manually sorted into grass, legume, and weed species. Forage DMI was estimated using a rising plate meter before and after grazing. Heifer BW at the conclusion of yr 1 and yr 2 did not differ between HO and HG (P = 0.40 and P = 0.12, respectively). Likewise, overall ADG did not differ between HO and HG, averaging 0.65 kg/d and 0.63 kg/d over both grazing seasons (P = 0.70). Grazing strategy did not affect forage or total DMI in yr 1; however, HO consumed 2.3 kg/d more forage DM than HG (P < 0.01), resulting in greater total DMI for HO in yr 2 (P < 0.01). Heights at the hip and withers were greater for HO than for HG during both grazing seasons (P < 0.05). Weed presence did not differ between grazing strategies over both grazing seasons as determined by manual harvesting, but visual estimation of botanical composition at the end of yr 2 showed that HO paddocks had 3.5 times more weed presence than HG pastures (P < 0.01). Within the confines of this study, co-grazing did not affect overall heifer BW gain, but it decreased DMI, suggesting that dairy heifers can be co-grazed with goats without negative effects on ADG or feed efficiency. PMID:22952353
Dennis, T S; Unruh-Snyder, L J; Neary, M K; Nennich, T D
The challenge for sustainable organic dairy farming is identification of cows that are well adapted to forage-based production systems. Therefore, the aim of this study was to compare the grazing behaviour, physical activity and metabolic profile of two different Holstein strains kept in an organic grazing system without concentrate supplementation. Twelve Swiss (HCH ; 566 kg body weight (BW) and 12 New Zealand Holstein-Friesian (HNZ ; 530 kg BW) cows in mid-lactation were kept in a rotational grazing system. After an adaptation period, the milk yield, nutrient intake, physical activity and grazing behaviour were recorded for each cow for 7 days. On three consecutive days, blood was sampled at 07:00, 12:00 and 17:00 h from each cow by jugular vein puncture. Data were analysed using linear mixed models. No differences were found in milk yield, but milk fat (3.69 vs. 4.05%, P = 0.05) and milk protein percentage (2.92 vs. 3.20%, P < 0.01) were lower in HCH than in HNZ cows. Herbage intake did not differ between strains, but organic matter digestibility was greater (P = 0.01) in HCH compared to HNZ cows. The HCH cows spent less (P = 0.04) time ruminating (439 vs. 469 min/day) and had a lower (P = 0.02) number of ruminating boli when compared to the HNZ cows. The time spent eating and physical activity did not differ between strains. Concentrations of IGF-1 and T3 were lower (P ? 0.05) in HCH than HNZ cows. In conclusion, HCH cows were not able to increase dry matter intake in order to express their full genetic potential for milk production when kept in an organic grazing system without concentrate supplementation. On the other hand, HNZ cows seem to compensate for the reduced nutrient availability better than HCH cows but could not use that advantage for increased production efficiency. PMID:24548047
Thanner, S; Schori, F; Bruckmaier, R M; Dohme-Meier, F
Although the nutritive value of chicory (Cichorium intybus L.) and plantain (Plantago lanceolata L.) has been thoroughly studied, little is known about the grazing behavior of cattle feeding on chicory and plantain swards. The objective of the present study was to assess and describe the grazing behavior of dairy cows as affected by dietary proportions of chicory and plantain fed as monocultures for part of the day. Ninety Holstein-Friesian cows (489±42 kg of body weight; 4.1±0.3 body condition score, and 216±15 d in milk) were randomly assigned to 15 groups (6 cows per group) and grazed according to 7 treatments: control (CTL, 3 groups), perennial ryegrass (Lolium perenne L.) dominant sward (24-h pasture strip); 3 chicory treatments comprising 20, 40, and 60% of the diet, strip-grazing a monoculture of chicory to a fixed postgrazing residual before strip-grazing a perennial ryegrass dominant sward (2 groups of cows per treatment); and 3 plantain treatments comprising 20, 40, and 60% of the diet, strip-grazing a monoculture of plantain to a fixed postgrazing residual before strip-grazing a perennial ryegrass dominant sward (2 groups of cows per treatment). Four focal animals per group were equipped with 3-dimensional motion sensors, which provided the number of steps taken at each minute of the day. These cows were also fitted with automatic jaw-movement recorders that identified bites, mastication during ingestion, chewing during rumination, and determined grazing, rumination and idling times and bouts. Daily grazing time and bouts were not affected by treatments but rumination time differed and was reduced by up to 90 min when cows were allocated to chicory and plantain as 60% of their diet. Ruminative chewing was reduced in cows grazing chicory and plantain by up to 20% in cows allocated to the 60% treatments. Compared with perennial ryegrass, as the dietary proportion of chicory and plantain increased, cows spent more time idling and less time ruminating, and increased ingestive mastications 5 and 3 times for chicory and plantain, respectively. Cows allocated to chicory and plantain reduced bite rate and bites per grazing step linearly, and increased the number of mastications per bite of pasture dry matter intake while grazing pasture after having grazed chicory and plantain. These results indicate that cows grazing chicory and plantain masticate more during ingestion and reduce rumination time and chewing. They also suggest that chicory presents greater constraints to ingestion than does plantain. Thus, although chicory has been considered to have a greater nutritive value than plantain, its overall feeding value may be no greater than that of plantain. PMID:24119808
Gregorini, P; Minnee, E M K; Griffiths, W; Lee, J M
This fact sheet summarizes the results of a three-tiered research approach (case study, two continuous culture fermenter studies, and a controlled research farm study) to evaluate molasses as an alternative supplement source for grazing dairy cows. A two-year case study of a New York organic dairy f...
The effects of virginiamycin, an agent active against Gram-positive lactic acid-producing bacteria, and NaHCO3 on ruminal and fecal pH, rumen volatile fatty acid proportions, blood metabolites, and milk production and composition were assessed. This study was conducted over 28 d and involved 71 dairy cows that grazed predominantly ryegrass, oats, and clover, and that were fed 10 kg of concentrate
E. H. Clayton; I. J. Lean; J. B. Rowe; J. W. Cox
The objective of this study was to explain the influence of green leaf allowance levels on the performance of dairy ewes grazing a tropical grass. Seventy-two lactating ewes grazed Aruana guineagrass (Panicum maximum Jacq. cv. Aruana) for 80 d. The treatments were 4 daily levels of green leaf allowance (GLA) on a DM basis corresponding to 4, 7, 10, and 13 kg DM/100 kg BW, which were named low, medium-low, medium-high, and high level, respectively. The experimental design was completely randomized with 3 replications. During the experimental period, 4 grazing cycles were evaluated in a rotational stocking grazing method (4 d of grazing and 16 d of rest). There was a linear effect of GLA on forage mass, and increasing GLA resulted in increased total leaf mass, reaching an asymptotic plateau around the medium-high GLA level. The stem mass increased with increased GLA, and a pronounced increase was observed between medium-high and high GLAs. Increasing GLA increased both forage disappearance rate and postgrazing forage mass. Leaf proportion increased with GLA, peaking at the medium-high level, and the opposite occurred for stem proportions, which reduced until medium-high GLA level, followed by an increase on high GLA. Forage CP decreased linearly with GLA, and increasing GLA from low to high reduced CP content by 31%. On the other hand, NDF increased 14% and ADF increased 26%, both linearly in response to greater GLA levels. Total digestible nutrients decreased linearly by 8% when GLA increased from low to high level. Milk yield increased, peaking at medium-high GLA (1.75 kg ewe(-1) d(-1)) and decreased at high GLA level (1.40 kg ewe(-1) d(-1)). Milk composition was not affected by the GLA levels. There was a reduction in stocking rate from 72 to 43 ewes/ha when GLA increased from low to high level. Productivity (milk yield kg ha(-1) d(-1)) increased as GLA increased, peaking at medium-low level (115 kg ha(-1) d(-1)). Although this tropical grass showed the same pattern in responses to GLA levels as reported in the literature with temperate pastures, the magnitude of the process changed and the maximum response in milk yield from lactating dairy ewes grazing a tropical pasture would be achieved with higher forage allowances than in temperate pastures. Overall, Aruana guineagrass grazed by lactating dairy ewes should be managed to provide 7 to 10 GLA in kg DM/100 kg BW according to the production goals. PMID:24671589
De Souza, J; Batistel, F; Ticiani, E; Sandri, E C; Pedreira, C G S; Oliveira, D E
Demand for organic dairy products has continually increased and at times outpaced supply for a number of years. This has created favorable milk pricing for certified organic dairy farmers, as the stability of organic milk prices has provided organic dairy farmers with a security not found in the con...
The objective of this study was to investigate the effect of initial spring grazing date and subsequent stocking rate on sward characteristics, grazing behavior, milk yield, and dry matter intake of spring-calving dairy cows during the main grazing season. Sixty-four spring-calving Holstein-Friesian dairy cows (58 +/- 9 d in milk) were balanced and randomly assigned to 1 of 4 grazing treatments (n = 16) between April 12, and July 3, 2004. Two swards, an early-grazed (E) sward and a late-grazed (L) sward had 2 stocking rates, high and medium, imposed across them. Cows grazing the E swards were stocked at 4.5 cows/ha (E4.5) and 5.5 cows/ha (E5.5), whereas cows grazing the L sward were stocked at 5.5 cows/ha (L5.5) and 6.4 cows/ha (L6.4). Sward characteristics, grazing behavior, and grass dry matter intake (GDMI) were investigated during the second (R2) and fourth grazing rotations (R4). Total dry matter yield was greater on L swards in R2. In R2, the E swards had a greater proportion of leaf as well as a lesser stem and dead dry matter yield. During R2, organic matter digestibility and crude protein content were greater on the E sward than the L sward. Pre-and postgrazing heights were greater for the L swards in R2 and R4. In R4, there was a larger leaf allowance on the E swards. Grazing time was greater and ruminating time lesser for animals grazing the E sward in R2. During R4, intake per bite was greater for the E5.5 and E4.5 treatments. Milk and solids-corrected milk yields as well as GDMI were greater for animals grazing the E sward in both R2 and R4. The results of the present study suggest that early grazing initially had a positive effect on sward quality and structure, which resulted in improved grazing behavior characteristics, increased GDMI, and increased milk production. During R4, sward quality and structure were similar between swards; thus, differences in grazing behavior were due to divergent daily herbage allowances. These results suggest that sward structure and quality as well as daily herbage allowance are important factors that influence animal performance and grazing behavior. PMID:17369246
Kennedy, E; O'Donovan, M; Murphy, J P; Delaby, L; O'Mara, F P
The objectives of this study were to describe the incidence of postpartum disease and to evaluate the association with serum cholesterol concentrations during the first 3 weeks after calving in grazing dairy cows. The association between non-esterified fatty acids (NEFA), ?-hydroxybutyrate (BHBA), calcium and postpartum diseases was also evaluated. A total of 307 Holstein dairy cows from 6 commercial grazing herds in Osorno, Chile, were monitored from calving until 21 days in milk. Cases of retained placenta, clinical hypocalcemia and clinical mastitis were recorded by the farmer using established definitions. Twice weekly, cows were evaluated for metritis by the same veterinarian based on vaginal discharge and body temperature. Postpartum blood samples were collected weekly and analyzed for serum concentrations of cholesterol, NEFA, BHBA and calcium. Cows were considered as having subclinical ketosis if BHBA >1.2 mmol/L, and subclinical hypocalcemia if calcium <2.0 mmol/L in any of the 3 weekly samples. Overall, 56% of the cows studied developed at least one clinical or subclinical disease after calving. Incidence of individual diseases was 8.8% for retained placenta, 4.2% for clinical hypocalcemia, 11.7% for clinical mastitis, 41.1% for metritis, 19.9% for subclinical hypocalcemia and 16.6% for subclinical ketosis. Lower postpartum cholesterol in cows was associated with developing severe metritis or having more than one clinical disease after calving. For every 0.4 mmol/L decrease in serum cholesterol cows were nearly twice as likely to be diagnosed with multiple clinical diseases after calving. Higher BHBA concentrations and lower calcium concentrations during week 1 were associated with severe cases of metritis. Low serum calcium concentration during week 1 was also associated with developing more than one clinical disorder after calving. In conclusion, the incidence of postpartum diseases can be high even in grazing herds and lower serum cholesterol concentrations were associated with occurrence of clinical postpatum disorders. PMID:25807462
Structural changes lead to increasing sizes of dairy herds and a reduction in grazing use. Thus, cows spend more time in the barn and become more exposed to the barn environment. The cubicle surface can result in damages of the cows' hock joint integument. Pasture is generally seen as a beneficial environment for cows. We hypothesized that a higher number of daily grazing hours reduce the probability of hock joint alterations in dairy cows from large herds. In total, 3148 lactating cows from 36 grazing and 20 zero-grazing dairy herds, with an average herd size of 173 cows, were assessed individually on one randomly selected body side for alterations in hock integument (score 0 for no alterations or hairless areas <2 cm, 1 for at least one hairless area of ?2 cm, 2 for lesion or swelling). The cows were further assessed for lameness and cleanliness. Information on breed, parity and days in milk per cow was extracted from a national database. Cubicle surface was evaluated for each herd. Daily grazing hours 30 days before herd visits were recorded by the stockmen and later categorized as follows: zero hours (zero-grazing), few hours (3 to 9) and many hours (>9 to 21). The effects of daily grazing hours and other potential cow and herd-level risk factors were evaluated for their impact on hock integument alterations using a logistic analysis with a multi-level model structure. The probability for hock integument alterations such as hair loss, lesions or swellings decreased with increasing amount of grazing hours (odds of 3 to 9 h 2.2 times and odds of >9 to 21 h 4.8 times lower than of zero-grazing). The probability for only lesions or swellings decreased with >9 to 21 grazing hours (odds 2.1 times) but not with 3 to 9 h (odds 1.0 times) compared with zero-grazing. Lameness, hard cubicle surface and Danish Holstein v. other breeds showed an increasing effect on the probability for integument alterations. Increase in days in milk only showed an increasing effect on the probability for lesions and swellings. We concluded that a long daily stay on pasture is most beneficial for the hock joint integument of a dairy cow. PMID:23031448
Burow, E; Thomsen, P T; Rousing, T; Sørensen, J T
This study investigated concentrations of various N species in shallow groundwater (<2.2m below ground level) and N losses from dairy production involving grazing over the winter period on a clay loam soil with a high natural attenuation capacity in southern Ireland (52°51'N, 08°21'W) over a 2-year period. A dense network of shallow groundwater piezometers was installed to determine groundwater flow direction and N spatial and temporal variation. Estimated vertical travel times through the unsaturated zone (<0.5 yr, time lag) allowed the correlation of management with groundwater N within a short space of time. There was a two way interaction of the system and sampling date (P<0.05) on concentrations of DON, oxidised N and NO(3)(-)-N. In contrast, concentrations of NH(4)(+)-N and NO(2)(-)-N were unaffected by the dairy system. Grazing over the winter had no effect on N losses to groundwater. Mean concentrations of DON, NH(4)(+)-N, NO(2)(-)-N and NO(3)(-)-N were 2.16, 0.35, 0.01 and 0.37 mg L(-1) respectively. Soil attenuation processes such as denitrification and DNRA resulted in increased NH(4)(+)-N levels. For this reason, DON and NH(4)(+)-N represented the highest proportion of N losses from the site. Some of the spatial and temporal variation of N concentrations was explained by correlations with selected chemical and hydro-topographical parameters (NO(3)(-)-N/Cl(-) ratio, distance of the sampling point from the closest receptor, watertable depth, depth of sampling piezometer, DOC concentration). A high explanatory power of NO(3)(-)-N/Cl(-) ratio and the distance of the sampling point from the closest receptor indicated the influence of point sources and groundwater-surface water interactions. PMID:22728303
Necpalova, M; Fenton, O; Casey, I; Humphreys, J
Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ? 2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle, respectively. Across the 2-yr trial, average daily gain for grazing heifer groups tended to be greater than heifers remaining in confinement (0.85 vs. 0.74 kg/d), but both management strategies produced weight gains within reasonable proximity to normal targets for heifers in this weight range. Fall-grown oat should be managed as stockpiled forage for deferred grazing, and good utilization of fall-oat forage can be accomplished by a one-time removal of standing forage, facilitated by a single lead wire advanced daily to prevent waste. PMID:24440262
Coblentz, W K; Brink, G E; Hoffman, P C; Esser, N M; Bertram, M G
The objectives of this study were to determine the effect of calving body condition score (BCS) on cow health during the transition period in a pasture-based dairying system. Feed inputs were managed during the second half of the previous lactation so that BCS differed at drying off (BCS 5.0, 4.0, and 3.0 for high, medium, and low treatments, respectively: a 10-point scale); feed allowance was managed after cows were dried off, such that the BCS differences established during lactation remained at the subsequent calving (BCS 5.5, 4.5, and 3.5; n=20, 18, and 19, for high, medium, and low treatments, respectively). After calving, cows were allocated pasture and pasture silage to ensure grazing residuals >1,600 kg of DM/ha. Milk production was measured weekly; blood was sampled regularly pre- and postpartum to measure indicators of health, and udder and uterine health were evaluated during the 6 wk after calving. Milk weight, fat, protein, and lactose yields, and fat content increased with calving BCS during the first 6 wk of lactation. The effect of calving BCS on the metabolic profile was nonlinear. Before calving, cows in the low group had lower mean plasma ?-hydroxybutyrate and serum Mg concentrations and greater mean serum urea than cows in the medium and high BCS groups, which did not differ from each other. During the 6 wk after calving, cows in the low group had lower serum albumin and fructosamine concentrations than cows in the other 2 treatment groups, whereas cows in the low- and medium-BCS groups had proportionately more polymorphonucleated cells in their uterine secretions at 3 and 5 wk postpartum than high-BCS cows. In comparison, plasma ?-hydroxybutyrate and nonesterified fatty acid concentrations increased linearly in early lactation with calving BCS, consistent with a greater negative energy balance in these cows. Many of the parameters measured did not vary with BCS. The results highlight that calving BCS and, therefore, BCS through early lactation are not effective indicators of functional welfare, with the analyses presented indicating that both low and high BCS at calving will increase the risk of disease: cows in the low group were more prone to reproductive compromise and fatter cows had an increased risk of metabolic diseases. These results are important in defining the welfare consequences of cow BCS. PMID:23871378
Roche, J R; Macdonald, K A; Schütz, K E; Matthews, L R; Verkerk, G A; Meier, S; Loor, J J; Rogers, A R; McGowan, J; Morgan, S R; Taukiri, S; Webster, J R
One hundred twenty-four cows (92 multiparous and 32 primiparous) were used to evaluate the effect of grain supplements containing high crude protein [(22.8% CP, 5.3% rumen undegradable protein (RUP), dry matter basis], moderate CP (16.6% CP, 6.1% RUP), and moderate CP with supplemental RUP (16.2% CP, 10.8% RUP) on lactation performance of Holstein cows rotationally grazing annual ryegrass-oat pastures. Supplemental protein was provided by solvent extracted soybean meal in the high CP and moderate CP supplements and as a corn gluten meal-blood meal mixture (2.8:1) in the moderate CP, high RUP supplement. Cows were blocked according to previous mature milk equivalent production and calving date (partum group; 0 d in milk or postpartum group; 21 to 65 d in milk) and randomly assigned to dietary treatments. Grain was individually fed, at approximately a 1:3 grain to milk ratio, before a.m. and p.m milkings. The study was replicated during two grazing seasons that averaged 199 d. Cows had ad libitum access to bermudagrass hay while on pasture (dry matter intake = 1.3 kg/d). Protein supplementation had no effect on study long pasture dry matter (12.7 +/- 1.0 kg/d) or total dry matter (23.9 +/- 1.2 kg/d) consumption. Protein concentration did not affect actual milk yield of either calving group (high CP vs. moderate CP); however, postpartum group cows receiving high CP grain supplements maintained greater milk fat concentrations (3.34 vs. 3.11%), which led to higher fat-corrected milk (FCM) yields than control cows receiving moderate CP grain diets (30.3 vs. 28.9 kg/d). Crude protein concentration in milk of high CP-supplemented, postpartum group cows was also higher than moderate CP cows (3.42 vs. 3.27%). Additional RUP did not increase FCM yield above that generated by moderate CP grain diets for partum (34.3 vs. 32.9 kg/d) or postpartum-group cows (28.9 vs. 28.2 kg/d). Increasing CP concentration of grain supplement did not affect milk yield of Holstein cows grazing immature winter annual pastures. Supplementing additional RUP was without benefit, indicating that in this study energy deprivation may have been the major nutritional constraint for high-producing dairy cows grazing lush pastures. PMID:11352166
McCormick, M E; Ward, J D; Redfearn, D D; French, D D; Blouin, D C; Chapa, A M; Fernandez, J M
The objective of this study was to determine the effect of adding fish oil (FO) and sunflower oil (SFO) to grazing dairy cows’ diets on the temporal changes in milk conjugated linoleic acid (cis-9, trans-11 CLA). Sixteen Holstein cows were divided into two diet regimen groups. One group (CONT) was fed a basal diet (7.6kg DM basis) plus 400g animal
A. A. AbuGhazaleh
The effects of supplementation with rapeseed, sun- flower, and linseed oils (0.5 kg\\/d; good sources of oleic, linoleic, and linolenic acids, respectively) on milk responses and milk fat fatty acid (FA) profile, with special emphasis on rumen-derived biohydrogenation intermediates (BI), were evaluated in a replicated 4 × 4 Latin square study using 16 grazing dairy cows. The dietary treatments were
J. Cabrita; J. B. Bess; Pólo Universitário
Contents The study investigated the influence of selected husbandry factors on interval to resumption of post-partum cyclicity among dairy cows in urban and peri-urban Kampala. A prospective study of 85 day post-partum period of 59 dairy cows in open (n = 38) and zero grazing (n = 21) systems was conducted on 24 farms. Cows of parity 1–6 were recruited starting 15–30 days post-partum. Progesterone (P4) content in milk taken at 10–12 day intervals was analysed using ELISA. The cow P4 profiles were classified into ‘normal’ (< 56 days), ‘delayed’ (> 56 days), ‘ceased’ or ‘prolonged’ (if started < 56 days but with abnormal P4 displays) resumption of luteal activity and tested for association with husbandry and cow factors. Of the 59 cows, luteal activity in 81.4% resumed normally and in 18.6%, delayed. Only 23.7% maintained regular luteal activity, while the others had ceased (10.2%), prolonged (37.3%) or unclear luteal activity (20.3%). There were no differences between open and zero-grazed cows. Milk production was higher (p < 0.05) in zero than open grazing, in urban than peri-urban and in cows fed on brew waste (p < 0.001) compared with mill products and banana peels. Results suggest that luteal activity resumes normally in a majority of cows, although only a minority experienced continued normal cyclicity once ovulation had occurred, in the two farming systems irrespective of feed supplements or water, and that supplementing with brew waste is beneficial for milk production. PMID:24930481
Kanyima, BM; Båge, R; Owiny, DO; Ntallaris, T; Lindahl, J; Magnusson, U; Nassuna-Musoke, MG
Environmental concerns for our farms include nutrient leaching to ground water, runoff in surface water, gaseous emissions, and the carbon footprint of our production systems. Recent reports have labeled grazing-based dairies as less environmentally sustainable compared to year around confinement sy...
The objective of this trial was to evaluate the effects of diet and cooling in the holding pen before milking on rectal temperature, respiration rate and milk production and composition. Fifty-eight lactating Holstein cows were used in a factorial split-plot design, at Rafaela Experimental Station from 12 January to 3 March 2003. The treatments were combinations of two diets: control (CD) and balanced (BD) with two levels of cooling before milking: none (NSF) and a sprinkler and fans (SF). Forage:concentrate ratios for CD and BD were 81:19 and 68:32, respectively. Cows were milked twice daily. Milk production was recorded daily, and milk composition (fat, protein, lactose and urea) was analysed twice a week. The physiological data were recorded once a week, before the cattle entered the holding pen and after milking, in the afternoon. Average maximum weekly temperature humidity index was 75.4 and ranged from 61.4 to 83. There were highly significant effects of cooling on physiological responses. Milk production was affected by diet and cooling, with no interaction; the highest and lowest production of milk was 22.42 and 20.07 l/cow per day, for BD+SF and CD+NSF, respectively. Protein was affected by diet, and was higher for BD (3.17 vs. 3.08%). There were interaction effects on milk fat at the 8% level, the highest concentration being 3.65% for BD+NFS. It was concluded that under grazing conditions, cooling by sprinkler and fans before milking improves the comfort of dairy cows, and that the effects on milk production and composition are enhanced when diets are specially formulated for heat-stress periods.
Gallardo, M. R.; Valtorta, S. E.; Leva, P. E.; Gaggiotti, M. C.; Conti, G. A.; Gregoret, R. F.
Due to increasing organic grain costs, organic dairy farmers are looking for less expensive ingredients that can be reasonably fed to lactating dairy cows. Molasses seems to be a less expensive source of supplemental energy and vitamins. Organic dairy farmers inquire about molasses as an alternative...
The objective of this study was to determine the long- termeffect onmilk conjugatedlinoleic acid(cis-9,trans- 11 CLA) of adding fish oil (FO) and sunflower oil (SFO) to the diets of partially grazing dairy cows. Fourteen Holstein cows were divided into 2 groups (7 cows\\/treat- ment) and fed either a control or oil-supplemented diet for 8 wk while partially grazing pasture. Cows
A. A. AbuGhazaleh; L. D. Holmes
The aim of the present study was the continuous measurement of ruminal pH in grazing dairy cows to monitor the diets effects on ruminal pH value. A novel indwelling pH-measurement and data transmitting system was given to 6 multiparous cows orally. Ruminal pH was measured every 600?sec over a 40?d period. After barn feeding and changeover to pasture, the following 3 treatments (2 cows/treatment) were included in the measurement period: continuous grazing (G), continuous grazing plus 4?kg/d of hay fed twice daily (GH), and continuous grazing plus 4?kg/d of concentrate (GC). Ruminal pH decreased significantly (P < 0.05) from 6.58 ± 0.15 to pH 6.19 ± 0.19 during feed changeover to pasture. Mean ruminal pH for G, GH, and GC was 6.36, 6.56, and 6.01. Mean 24-h minimum pH was 5.95, 6.20 and, 5.58. The time pH was below 6.3, 6.0, 5.8, and 5.5, for G it was 583, 91, 26, and 3?min/d, for GH it was 97, 12, 0, and 0?min/d and for GC it was 1126, 621, 347, and 101?min/d, respectively. Results were significantly influenced by the diet. The indwelling pH-measurement and data transmitting system is a very useful and proper tool for long-term measurement of ruminal pH in cows. PMID:23213627
Gasteiner, J.; Guggenberger, T.; Häusler, J.; Steinwidder, A.
Ultra-high stocking density (UHSD) grazing has gained interest in the forage industry. Proponents of UHSD emphasize increased forage use efficiency and soil improvement by grazing mature forage with stocking densities up to 560,425 kg ha**-1 of beef cattle on small paddocks with rest periods of up t...
The utilisation of dual-purpose crops, especially wheat and canola grown for forage and grain production in sheep-grazing systems, is reviewed. When sown early and grazed in winter before stem elongation, later-maturing wheat and canola crops can be grazed with little impact on grain yield. Recent research has sought to develop crop- and grazing-management strategies for dual-purpose crops. Aspects examined have been grazing effects on crop growth, recovery and yield development along with an understanding of the grazing value of the crop fodder, its implications for animal nutrition and grazing management to maximise live-weight gain. By alleviating the winter 'feed gap', the increase in winter stocking rate afforded by grazing crops allows crop and livestock production to be increased simultaneously on the same farm. Integration of dual-purpose wheat with canola on mixed farms provides further systems advantages related to widened operational windows, weed and disease control and risk management. Dual-purpose crops are an innovation that has potential to assist in addressing the global food-security challenge. PMID:24323974
Dove, Hugh; Kirkegaard, John
~-~ash Wheat ? Ina B~1452 November 1983 t Wheat--Ryegrass Grazing System ~ THE TEXAS AGRICULTURAL EXPERIMENT STATION / Neville P. Clarke, Director / The Texas A&M University System / College Station, 'l"exas SUMMARY Wheat is an important...
Nelson, L.R.; Rouquette, F.M. Jr.; Randel, R.D.
Organic dairies in New York face challenges, including the high cost of purchasing organic feed grains. Many of these farms are looking for alternative ingredients to use that can be reasonably fed to lactating dairy cows, and that are less costly. Molasses seems to be a viable, less expensive, so...
Organic dairies face many challenges, one of which is the high cost of purchasing organic feed grains. Many of these farms are seeking lower-cost feed ingredients that can be reasonably fed to lactating dairy cows. Molasses seems to be a viable, less expensive source of supplemental energy and vit...
Ruminant livestock provides meat and dairy products that sustain health and livelihood for much of the world's population. Grazing lands that support ruminant livestock provide numerous ecosystem services, including provision of food, water, and genetic resources; climate and water regulation; support of soil formation; nutrient cycling; and cultural services. In the U.S. southern Great Plains, beef production on pastures, rangelands, and hay is a major economic activity. The region's climate is characterized by extremes of heat and cold and extremes of drought and flooding. Grazing lands occupy a large portion of the region's land, significantly affecting carbon, nitrogen, and water budgets. To understand vulnerabilities and enhance resilience of beef production, a multi-institutional Coordinated Agricultural Project (CAP), the "grazing CAP," was established. Integrative research and extension spanning biophysical, socioeconomic, and agricultural disciplines address management effects on productivity and environmental footprints of production systems. Knowledge and tools being developed will allow farmers and ranchers to evaluate risks and increase resilience to dynamic conditions. The knowledge and tools developed will also have relevance to grazing lands in semiarid and subhumid regions of the world. PMID:25376887
Steiner, Jean L; Engle, David M; Xiao, Xiangming; Saleh, Ali; Tomlinson, Peter; Rice, Charles W; Cole, N Andy; Coleman, Samuel W; Osei, Edward; Basara, Jeffrey; Middendorf, Gerad; Gowda, Prasanna; Todd, Richard; Moffet, Corey; Anandhi, Aavudai; Starks, Patrick J; Ocshner, Tyson; Reuter, Ryan; Devlin, Daniel
Smallholder dairy farmers in the Kenya highlands generally intensify their farming systems by integrating dairy with crop production and shifting from free-grazing to semi-zero- or zero-grazing. They consequently change the breed composition, size and structure of their herds with resultant change in herd demographic rates. The intensification of smallholder dairying has underpinned changes in the farming systems to sustain more
B. O. Bebe
This work was conducted to investigate the effect of supplementing grazing ewes on pasture with a cereal concentrate on the milk fatty acid (FA) profile. Ninety Assaf ewes in mid lactation were distributed in 9 lots of 10 animals each and allocated to 3 feeding regimens: 1) pasture--ewes were only allowed to graze pasture (an irrigated sward of Lolium perenne, Trifolium pratense, and Dactylis glomerata); 2) PS--grazing ewes were supplemented with oat grain (700 g/animal and day); and 3) TMR--ewes were fed ad libitum a total mixed ration (TMR; 80:20 concentrate/forage ratio). Milk yield and composition were recorded for 5 wk. The highest milk yield was observed in ewes receiving the TMR and the lowest in grazing ewes supplemented with oat grain. Productions of milk fat, protein, and total solids showed the lowest values in treatment PS. The atherogenicity index, which comprises C12:0, C14:0, and C16:0, in PS milk fat was no different from that observed in milk from animals on pasture (1.53 for pasture, 1.54 for PS, and 3.22 for TMR). Oat grain supplementation generated higher amounts of C18:0 and cis-9 C18:1 in milk fat than the pasture-only diet, but significantly decreased the levels of alpha-linolenic acid and most of intermediates of the process of biohydrogenation of this FA. Cis-9 trans-11 C18:2 and trans-11 C18:1, its precursor for endogenous synthesis in the mammary gland, were lower in PS (0.58 and 1.59 g/100 g of total FA) than in TMR (0.72 and 1.92 g/100 g of total FA) and very different from the results observed in grazing ewes receiving no supplement (1.21 and 3.88 g/100 g of total FA). Furthermore, the lowest levels of trans-10 C18:1 and trans-10 cis-12 C18:2 were detected in the milk fat of ewes fed pasture. It is concluded that, when pasture quality and availability do not limit dairy production, supplementation of grazing ewes with oat grain compromised the milk FA profile without any significant positive effect on milk production. PMID:19620680
Gómez-Cortés, P; Frutos, P; Mantecón, A R; Juárez, M; de la Fuente, M A; Hervás, G
Systems of Grazing. (May 1991) Fabian de Achaval O'Farrell, Ingeniero en Produccion Agropecuhria, Universidad Catolica Argentina; Chair of Advisory Committee: Dr. W. C. Ellis The objectives of this research were to: 1) compare ADG and gain...
Achaval O'Farrell, Fabian de
Effects of grazing system, stocking rate, and grazing system X stocking rate interactions, on plant diversity are poorly understood in rangelands. A grazing system (season-long and short-duration rotational grazing) X stocking rate (light: 16 steers•80 ha-1, moderate: 4 steers•12 ha-1 and heavy: 4 s...
SUMMARY The efficiency of herbage utilization from alfalfa-bromegrass (M. falcata and B. inermis) pasture under rotational and strip-grazing management was compared for three grazing seasons. The expression of increased efficiency as increased carrying capacity was precluded by restricting grazing, so that the cows on each system had equal opportunity to utilize the available herbage. Under these restrictions, dairy cows at
A. L. Brundage; W. J. Sweetman
The objective of this study was to evaluate how previous grazing experience affects animal behavior on pasture. Animal behavior was monitored in 32 Holstein (n = 21) and Holstein-Jersey (n = 11) yearlings. Two heifer groups (n = 8 per group) had been exposed to pasture from August through October 20...
Animal trials cannot be used in routine in a forage grass-breeding programme or in a cultivar testing procedure. An alternative to these animal trials is to identify plant traits associated with a high animal production under grazing that could be used as selection criteria. For this, the effect of sward structure on milk production was studied, comparing four late-heading diploid
Manuel FLORES-LESAMAa; Laurent Hazard; Michèle Betin; Jean-Claude Emile
Organic dairies face many challenges, one of which is the high cost of purchased organic grains. Molasses may be a less expensive energy alternative. However, anecdotal results have been mixed for farms that used molasses as the sole energy source. This research project quantified animal performance...
Pasture is rich in soluble nitrogen (N) which is rapidly converted to ammonia in the rumen reducing N utilization in lactating dairy cows. Sucrose is more quickly degraded in the rumen than starch, suggesting that feeding molasses (MOL) to balance the supplies of energy and rumen degradable protein...
Probabilistic Risk Assessment (PRA) techniques were used to evaluate the risk of contamination of surface and ground water with wastewater from an open lot dairy in Erath County, Texas. The dairy supported a complex waste management system...
Leigh, Edward Marshall
Cattle grazing in riparian areas can reduce water quality, alter stream channel characteristics, and alter fish and macroinvertebrate\\u000a assemblage structure. The U.S. Department of Agriculture, Natural Resources Conservation Services has recommended Rotational\\u000a Grazing (RG) as an alternative management method on livestock and dairy operations to protect riparian areas and water quality.\\u000a We evaluated 13 stream channel characteristics, benthic macroinvertebrate larvae
Kara L. Raymond; Bruce Vondracek
Greenhouse gas (GHG) emissions and their potential impact on global warming has become an important national and international concern. Dairy production systems along with all other types of animal agriculture are recognized as a source of GHG. Although little information exists on the net GHG emiss...
The effects of supplementation with rapeseed, sunflower, and linseed oils (0.5 kg/d; good sources of oleic, linoleic, and linolenic acids, respectively) on milk responses and milk fat fatty acid (FA) profile, with special emphasis on rumen-derived biohydrogenation intermediates (BI), were evaluated in a replicated 4 x 4 Latin square study using 16 grazing dairy cows. The dietary treatments were 1) control diet: 20-h access to grazing pasture supplemented with 5 kg/d of corn-based concentrate mixture (96% corn; CC); 2) RO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of rapeseed oil; 3) SO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of sunflower oil; and 4) LO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of linseed oil. Milk fatty acids were converted to methyl esters and analyzed by gas-liquid chromatography and silver-ion HPLC. Dietary treatments had no effect on milk production or on milk protein content and milk protein production. Supplementation with rapeseed and sunflower oils lowered milk fat content and milk fat production, but linseed oil had no effect. Inclusion of dietary vegetable oils promoted lower concentrations of short-chain (including 4:0) and medium-chain FA (including odd- and branched-chain FA) and 18:3n-3, and higher concentrations of C(18) FA (including stearic and oleic acids). The BI concentration was higher with the dietary inclusion of vegetable oils, although the magnitude of the concentration and its pattern differed between oils. The RO treatment resulted in moderate increases in BI, including trans 18:1 isomers and 18:2 trans-7,cis-9, but failed to increase 18:1 trans-11 and 18:2 cis-9,trans-11. Sunflower oil supplementation resulted in the highest concentrations of the 18:1 trans-10, 18:1 cis-12, and 18:2 trans-10,trans-12 isomers. Concentrations of 18:1 trans-11 and 18:2 cis-9,trans-11 were higher than with the control and RO treatments but were similar to the LO treatment. Concentration of BI in milk fat was maximal with LO, having the highest concentrations of some 18:1 isomers (i.e., trans-13/14, trans-15, cis-15, cis-16), most of the nonconjugated 18:2 isomers (i.e., trans-11,trans-15, trans-11,cis-15, cis-9,cis-15, and cis-12,cis-15), and conjugated 18:2 isomers (i.e., trans-11,cis-13, cis-12,trans-14, trans-11,trans-13, trans-12,trans-14, and trans-9,trans-11), and all conjugated 18:3 isomers. The LO treatment induced the highest amount and diversity of BI without decreasing milk fat concentration, as the RO and SO treatments had, suggesting that the BI associated with 18:3n-3 intake may not be the major contributors to inhibition of mammary milk fat synthesis. PMID:19700715
Rego, O A; Alves, S P; Antunes, L M S; Rosa, H J D; Alfaia, C F M; Prates, J A M; Cabrita, A R J; Fonseca, A J M; Bessa, R J B
Some dairy farmers and consumers are proponents of a diet for dairy cows with 100% pasture and no supplementation, similar to a New Zealand system. However, for US dairy producers who are thinking about a “100% pasture” system, this may not be a reality. Even during the 6 to 7 months grazing period,...
The effect of a regular anthelmintic treatment during the grazing period on milk production and milk composition was measured in a dairy goat farm. One month before turnout, 92 goats were given 10 mg.kg-1 febantel and then allocated to 2 equivalent groups according to their levels of milk production. The first group was given febantel monthly, the second group was kept as an untreated control. Parasitological, haematological and serological data were collected monthly from March to September. Milk production data were recorded from March to August, goats being dried up in September. Results of strongyle egg counts, serum inorganic phosphate concentrations and 4 necroscopic examinations indicated a low level of nematode infection composed almost exclusively with Trichostrongylus colubriformis in untreated goats. No significant changes in milk yield, fat and protein content were detected between treated and untreated groups. Moreover, the impact of monthly anthelmintic treatment on milk production was different depending on the initial level of milk yield. Anthelmintic treatment induced a 4-8% increase in milk production for goats with the highest milk yield at the start of the experiment, whereas no beneficial effects were recorded for goats with the lowest milk yield. PMID:7951347
Chartier, C; Hoste, H
Wisconsin Agricultural and Food Systems Network: Dairy Systems Sustainability Metrics Request for proposals We are pleased to announce a request for proposals that evaluate sustainability practices of Agriculture, Trade and Consumer Protection (DATCP), Wisconsin Cheese Makers Association, Wisconsin Milk
The aim of this work was to investigate the variations of milk fatty acid (FA) composition because of changing paddocks in two different rotational grazing systems. A total of nine Holstein and nine Montbéliarde cows were divided into two equivalent groups according to milk yield, fat and protein contents and calving date, and were allocated to the following two grazing systems: a long duration (LD; 17 days) of paddock utilisation on a heterogeneous pasture and a medium duration (MD) of paddock utilisation (7 to 10 days) on a more intensively managed pasture. The MD cows were supplemented with 4 kg of concentrate/cow per day. Grazing selection was characterised through direct observations and simulated bites, collected at the beginning and at the end of the utilisation of two subsequent MD paddocks, and at the same dates for the LD system. Individual milks were sampled the first 3 days and the last 2 days of grazing on each MD paddock, and simultaneously also for the LD system. Changes in milk FA composition at the beginning of each paddock utilisation were highly affected by the herbage characteristics. Abrupt changes in MD milk FA composition were observed 1 day after the cows were moved to a new paddock. The MD cows grazed by layers from the bottom layers of the previous paddock to the top layers of the subsequent new paddock, resulting in bites with high organic matter digestibility (OMD) value and CP content and a low fibre content at the beginning of each paddock utilisation. These changes could induce significant day-to-day variations of the milk FA composition. The milk fat proportions of 16:0, saturated FA and branched-chain FA decreased, whereas proportions of de novo-synthesised FA, 18:0, c9-18:1 and 18:2n-6 increased at paddock change. During LD plot utilisation, the heterogeneity of the vegetation allowed the cows to select vegetative patches with higher proportion of leaves, CP content, OMD value and the lowest fibre content. These small changes in CP, NDF and ADF contents of LD herbage and in OMD values, from the beginning to the end of the experiment, could minimally modify the ruminal ecosystem, production of precursors of de novo-synthesised FA and ruminal biohydrogenation, and could induce only small day-to-day variations in the milk FA composition. PMID:25483022
Coppa, M; Farruggia, A; Ravaglia, P; Pomiès, D; Borreani, G; Le Morvan, A; Ferlay, A
Twenty multiparous Holstein cows (four ruminally cannulated) in five 4 x 4 Latin squares with 21-d periods were used to study the effect of concentrate supplementation when grazed at two pasture allowances. The four dietary treatments resulted from the combination of two pasture allowance targets (low, 25 vs. high, 40 kg of dry matter/cow per day) and two concentrate supplementation levels (zero vs. 1 kg of concentrate/4 kg of milk). Concentrate supplementation decreased pasture dry matter intake 2.0 kg/d at the low pasture allowance (17.5 vs. 15.5 kg/d) and 4.4 kg/d at the high pasture allowance (20.5 vs. 16.1 kg/d). Substitution rate was lower at the low pasture allowance (0.26 kg pasture/kg concentrate) than at the high pasture allowance (0.55 kg of pasture/kg of concentrate). Total dry matter intake of both supplemented treatments averaged 24.4 kg/d. Milk production of both supplemented treatments averaged 29.8 kg/d, but was increased with higher pasture allowance in the unsupplemented treatments (19.1 vs. 22.2 kg/d). Milk response to concentrate supplementation was 1.36 and 0.96 kg of milk/kg of concentrate for the low and high pasture allowances, respectively. Concentrate supplementation reduced milk fat percentage but increased milk protein percentage. Rumen pH and NH3-N concentration were decreased with concentrate supplementation. Substitution rate was likely related to both negative associative effects in the rumen (reductions in rumen pH, rate of pasture digestion, and NDF digestibility) and reductions in grazing time. The latter was more important, quantitatively explaining at least 80% of the reduction in pasture dry matter intake observed. PMID:12201529
Bargo, F; Muller, L D; Delahoy, J E; Cassidy, T W
Grazing systems occupy more of the terrestrial biosphere than any other form of land use, with arid and semi-arid regions supporting disproportionately larger grazing area than other biomes. Two common responses of dryland ecosystems to grazing practices are desertification and woody encroachment, with the former occurring in more arid zones and the latter becoming prevalent in mesic areas. Desertification and woody encroachment are linked to ecosystem impoverishment and land-use abandonment. Desertification leads to fragmented ecosystem structure and decreased carbon storage. Woody encroachment results in increased structural heterogeneity of the landscape, elevated carbon stores aboveground, and variable belowground carbon responses. Nitrogen accumulates under woody plants in both desertification and woody encroachment scenarios, but large-scale changes in nitrogen stocks and trace gas fluxes differ substantially between these types of land degradation. New remote sensing approaches based on imaging spectroscopy allow regional-scale estimates of carbon and nitrogen dynamics that will increase our understanding of desertification and woody encroachment in global grazing systems.
Asner, Gregory P.; Martin, Roberta E.
The objective of this study was to investigate the immediate and carryover effects of imposing two post-grazing sward heights (PGSH) for varying duration during early lactation on sward characteristics and dairy cow production. The experiment was a randomised block design with a 2×2 factorial arrangement of treatments. A total of 80 spring-calving (mean calving date - 6 February) dairy cows were randomly assigned, pre-calving, to one of the two (n=40) PGSH treatments - S (2.7 cm) and M (3.5 cm) - from 13 February to 18 March, 2012 (P1). For the subsequent 5-week period (P2: 19 March to 22 April, 2012), half the animals from each P1 treatment remained on their treatment, whereas the other half of the animals switched to the opposing treatment. Following P2, all cows were managed similarly for the remainder of the lactation (P3: 23 April to 4 November, 2012) to measure the carryover effect. Milk production, BW and body condition score were measured weekly, and grass dry matter intake (GDMI) was measured on four occasions - approximately weeks 5, 10, 15 and 20 of lactation. Sward utilisation (above 2.7 cm; P1 and P2) was significantly improved by reducing the PGSH from 3.5 (0.83) to 2.7 cm (0.96). There was no effect of PGSH on cumulative annual grass dry matter (DM) production (15.3 t DM/ha). Grazing to 2.7 cm reduced GDMI by 1.7 and 0.8 kg DM/cow in P1 and P2, respectively, when compared with 3.5 cm (13.3 and 14.0 kg/cow per day, respectively). Cows grazing to 2.7 cm for both P1 and P2 (SS) tended to have reduced cumulative 10-week milk yield (-105 kg) and milk solids yield (-9 kg) when compared with cows grazing to 3.5 cm for both periods (MM; 1608 and 128 kg/cow, respectively). Treatments that alternated PGSH at the end of P1, SM and MS had intermediate results. There was no interaction between P1 and P2 treatments. There was also no carryover effect of early lactation grazing regime on milk and milk solids production in P3, given the reduction in early lactation milk yield. The results indicate that the diet of dairy cows should not be restricted by imposing a severe PGSH for all of the first 10 weeks of lactation, cows should graze to 3.5 cm for at least 5 of these weeks. PMID:25471149
Crosse, M; O'Donovan, M; Boland, T M; Delaby, L; Ganche, E; Kennedy, E
Background The present study hypothesized that GH-AluI and IGF-I-SnabI polymorphisms do change the metabolic/endocrine profiles in Holstein cows during the transition period, which in turn are associated with productive and reproductive parameters. Methods Holstein cows (Farm 1, primiparous cows, n = 110, and Farm 2, multiparous cows, n = 76) under grazing conditions were selected and GH and IGF-I genotypes were determined. Blood samples for metabolic/endocrine determinations were taken during the transition period and early lactation in both farms. Data was analyzed by farm using a repeated measures analyses including GH and IGF-I genotypes, days and interactions as fixed effects, sire and cow as random effects and calving date as covariate. Results and Discussion Frequencies of GH and IGF-I alleles were L:0.84, V:0.16 and A:0.60, B:0.40, respectively. The GH genotype was not associated with productive or reproductive variables, but interaction with days affected FCM yield in multiparous (farm 2) cows (LL yielded more than LV cows) in early lactation. The GH genotype affected NEFA and IGF-I concentrations in farm 1 (LV had higher NEFA and lower IGF-I than LL cows) suggesting a better energy status of LL cows. There was no effect of IGF-I genotype on productive variables, but a trend was found for FCM in farm 2 (AB cows yielded more than AA cows). IGF-I genotype affected calving first service interval in farm 1, and the interaction with days tended to affect FCM yield (AB cows had a shorter interval and yielded more FCM than BB cows). IGF-I genotype affected BHB, NEFA, and insulin concentrations in farm 1: primiparous BB cows had lower NEFA and BHB and higher insulin concentrations. In farm 2, there was no effect of IGF-I genotype, but there was an interaction with days on IGF-I concentration, suggesting a greater uncoupling somatropic axis in AB and BB than AA cows, being in accordance with greater FCM yield in AB cows. Conclusion The GH and IGF-I genotypes had no substantial effect on productive parameters, although IGF-I genotype affected calving-first service interval in primiparous cows. Besides, these genotypes may modify the endocrine/metabolic profiles of the transition dairy cow under grazing conditions. PMID:21635772
The effects on milk composition and processing characteristics of varying grass supply by changing stocking density and of offering a concentrate supplement were investigated. The experiment was conducted over 28 weeks of the lactation (April-October) using 48 spring-calved Friesian-Holstein cows. Three herds each of 16 cows were offered a restricted grass supply, a standard grass supply and a standard grass supply with a supplement of 3 kg concentrate/d. Treatment groups were grazed separately with a residence time of 3 d/paddock. Milk production, composition and processing characteristics such as renneting properties, ethanol stability and plasmin activity were measured weekly. Increasing stocking density above the standard system resulted in significant reductions in milk fat and protein yields, the concentrations of total protein, casein and whey proteins, and a deterioration in most processing characteristics. Imposing concentrate supplementation on the standard system increased total protein, casein and whey protein concentrations but generally did not improve processing characteristics except for ethanol stability. These results suggest that the standard grass supply in a rotational grazing paddock system can support efficient production of quality milk, and concentrate supplementation will not improve processing characteristics when an adequate supply of good quality herbage is available. PMID:10376239
O'Brien, B; Dillon, P; Murphy, J J; Mehra, R K; Guinee, T P; Connolly, J F; Kelly, A; Joyce, P
The effects of stocking rate and grazing system on gains of yearling beef cattle grazing rangelands have largely been addressed in short-term (<10 yr) studies, and often stocking rates are confounded within grazing systems with higher stocking rates for short-duration rotational grazing systems comp...
The objectives of this study were to assess the effect of the stage of estrous cycle on the percentage of endometrial polymorphonuclear cells (PMN) obtained by cytobrush to determine cutoff values for the diagnosis of subclinical endometritis under pastoral conditions, to measure the prevalence of subclinical endometritis 21 to 62d in milk (DIM), and to evaluate the effect of subclinical endometritis on reproductive performance in grazing dairy cows. The first experiment was conducted on a commercial dairy farm in Buenos Aires province (Argentina), where 17 postpartum cyclic dairy cows without clinical endometritis were selected and synchronized by Ovsynch protocol. Endometrial cytology (cytobrush technique) and blood (tail vessels) samples were obtained on d0, 4, 11, and 18 of the estrous cycle (corresponding to estrus, metestrus, diestrus, and proestrus, respectively) and used for measuring percentage of PMN and P4 concentration, respectively. The percentage of PMN was determined 3times by blinded count by 2 operators. Data were analyzed with PROC MIXED, PROC GENMOD, and PROC FREQ from SAS 9.1. The percentage of PMN did not vary with the stage of the estrous cycle. In addition, PMN counts were below any of the reported thresholds in this study (4%) for most of the cows. Therefore, the risk for false positive test results as a consequence of physiological changes in the counts of PMN during estrous cycle is low. The second experiment was conducted on 4 commercial dairy farms in Buenos Aires province (Argentina), where lactating Holstein dairy cows (n=418) 21 to 62 DIM without clinical endometritis were studied. Samples of endometrial cytology were collected with the cytobrush technique. Data were analyzed with receiver operator characteristic curves with Sigmaplot 10.0, and with PROC GLIMMIX, PROC PHREG, and PROC LIFETEST from SAS 9.1. Cutoff values for the diagnosis of subclinical endometritis in grazing dairy cows are 8% PMN for 21 to 33 DIM, 6% PMN for 34 to 47 DIM, 4% PMN for 48 to 62 DIM, and overall 5% PMN for 21 to 62 DIM; the prevalence of subclinical endometritis 21 to 62 DIM was 17%. Finally, subclinical endometritis diagnosed at 21 to 62 DIM decreases the hazard for pregnancy (hazard ratio=0.668; 95% confidence interval=0.492-0.909) and increases the calving to conception interval by d30 compared with normal cows (median 95% confidence interval=133 vs. 93, respectively). PMID:23684026
Madoz, L V; Giuliodori, M J; Jaureguiberry, M; Plöntzke, J; Drillich, M; de la Sota, R L
Grazing dairy cows expend more energy than confined dairy cows due to grazing activity as well as walking between the pasture and the milking parlor twice a day. The amount of energy expended depends on a variety of factors, including weather, slope, and distance. This summary article was developed ...
Managing the mineral nutrition of free-range grazing livestock can be challenging. On farms where grazing animals are infrequently yarded, there are limited opportunities to administer trace element supplements via feeds and concentrates. In New Zealand, where the majority of sheep, cattle, and deer graze pasture year round, inadequate intake of cobalt, copper, iodine and selenium is prevalent. Scientists and farmers have developed efficient strategies to monitor and treat these dietary deficiencies. Supplementation methods suited to grazing livestock include long-acting injections, slow-release intraruminal boluses, trace element-amended fertilisers, and reticulated water supplies on dairy farms. PMID:23316417
Grace, Neville D.; Knowles, Scott O.
Land redistribution was legislated in 1994; it was designed to resolve historical imbalances inland ownership in South Africa. Between 2002 and 2006, a longitudinal observational studywas conducted with 15 purposively selected small-scale dairy farmers in a land redistributionproject in Central North West Province. Four farmers left the project over the period. For thepurposes of this study, a small-scale dairy farm was defined as a farm that produces less than500 L of milk a day, irrespective of the number of cows or size of the farm. The study wasconducted in three phases. In the first phase, situational analysis using participatory ruralappraisal (PRA) and observation was used to outline the extent of the constraints and designappropriate interventions. Feeds that were used were tested and evaluated. In the secondphase, three different feeding systems were designed from the data obtained from PRA. Thesewere: (1) A semi-intensive farm-based ration using available crops, pastures and crop residueswith minimal rations purchased. (2) An intensive, zero-grazing dairy system using a totalmixed ration. (3) A traditional, extensive or dual-purpose system, where the calf drank fromthe cow until weaning and milking was done only once a day. In the third phase, adoptionwas monitored. By July 2006, all remaining farmers had changed to commercially formulatedrations or licks and the body condition score of the cows had improved. It was concluded thatveterinary extension based on PRA and a holistic systems approach was a good option forsuch complex problems. Mentoring by commercial dairy farmers, veterinary and extensionservices appeared to be viable. Further research should be done to optimise the traditionalmodel of dairy farming, as this was relatively profitable, had a lower risk and was less labourintensive. PMID:25026955
Manzana, N Patience; McCrindle, Cheryl M E; Sebei, P Julius; Prozesky, Leon
Tropical grasses are the primary nutrient resource for cattle production in the tropics, and they provide low-cost nutrients to cattle. However, its production is constrained by seasonal changes and quality; hence, appropriate usage of relatively inexpensive agricultural by-products is important to profitable livestock production. The objective of the study was to evaluate the effect of supplementing coffee pulp to dairy cows grazing tropical grasses on milk yield and forage intake. Four multiparous crossed Holstein-Brown Swiss-Zebu cows of similar weight and milk yield were used. The effect of 10%, 15% and 20% inclusion of coffee pulp in dairy concentrates on milk yield and forage intake was analysed using a 4 × 4 Latin square design. Results showed that there were no significant effects (P > 0.05) in grass dry matter intake, milk yield, milk composition body weight and body condition score due to the inclusion of coffee pulp in the dairy concentrates. It is concluded that coffee pulp can be included at levels of 20% in the concentrate without compromising significantly (P > 0.05) milk yield, milk composition and grass dry matter intake. It also was concluded that cost of concentrate is reduced in 20% by the inclusion of coffee pulp. PMID:22119887
Pedraza-Beltrán, Paulina; Estrada-Flores, Julieta G; Martínez-Campos, Angel R; Estrada-López, Isael; Rayas-Amor, Adolfo A; Yong-Angel, Gilberto; Figueroa-Medina, Marisol; Nova, Francisca Avilés; Castelán-Ortega, Octavio A
A prospective cohort study was conducted in five purposively-sampled agro-ecological zone (AEZ)-grazing system strata in Murang'a District, Kenya, between March 1995 and June 1996. The study strata were selected based on a preliminary characterization study to represent the widest range of risks to East Coast fever (ECF) in the District and included zero-grazing and open-grazing farms. In total, 225 calves from 188 smallholder farms were examined from birth to 6 months of age and visited within the first 2 weeks of life and thereafter at bi-weekly intervals for up to 14 visits. The purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity and mortality) and potential control of ECF between the selected strata. Evidence of Theileria parva infection was assessed by increased antibody levels as measured in an indirect ELISA assay by the percent positivity (PP) of serum samples relative to a strong positive reference serum. Sero-conversion risks of T. parva were highest in the open-grazing strata. Antibody prevalence in adult cattle and ECF morbidity and mortality risks were also highest in open-grazing strata. While different, all five AEZ-grazing strata were considered to be endemically unstable for ECF. East Coast fever challenge was low in all zero-grazing strata and this challenge is likely to remain low due to continuing intensification of smallholder farming in the central highlands. In the open-grazing strata, there was higher challenge and a greater impact of ECF. PMID:10813159
Gitau, G. K.; McDermott, J. J.; Katende, J. M.; O'Callaghan, C. J.; Brown, R. N.; Perry, B. D.
I suggest a spiral-in process in which a stellar companion grazes the envelope of a giant star while both the orbital separation and the giant radius shrink simultaneously, forming a close binary system. The binary system might be viewed as evolving in a constant state of "just entering a common envelope (CE) phase." In cases where this process takes place, it can be an alternative to CE evolution where the secondary star is immersed in the giant's envelope. Grazing envelope evolution (GEE) is made possible only if the companion manages to accrete mass at a high rate and launches jets that remove the outskirts of the giant envelope, hence preventing the formation of a CE. The high accretion rate is made possible by the accretion disk launching jets which efficiently carry the excess angular momentum and energy from the accreted mass. The orbital decay itself is caused by the gravitational interaction of the secondary star with the envelope inward of its orbit, i.e., dynamical friction (gravitational tide). Mass loss through the second Lagrangian point can carry additional angular momentum and envelope mass. The GEE lasts for tens to hundreds of years. The high accretion rate, with peaks lasting from months to years, might lead to a bright object referred to as the intermediate luminosity optical transient (Red Novae; Red Transients). A bipolar nebula and/or equatorial ring are formed around the binary remnant.
High intensity low frequency ultrasound was used to process dairy ingredients to improve functional properties. Based on a number of lab-scale experiments, several experimental parameters were optimised for processing large volumes of whey and casein-based dairy systems in pilot scale ultrasonic reactors. A continuous sonication process at 20 kHz capable of delivering up to 4 kW of power with a flow-through reactor design was used to treat dairy ingredients at flow rates ranging from 200 to 6000 mL/min. Dairy ingredients treated by ultrasound included reconstituted whey protein concentrate (WPC), whey protein and milk protein retentates and calcium caseinate. The sonication of solutions with a contact time of less than 1 min and up to 2.4 min led to a significant reduction in the viscosity of materials containing 18% to 54% (w/w) solids. The viscosity of aqueous dairy ingredients treated with ultrasound was reduced by between 6% and 50% depending greatly on the composition, processing history, acoustic power and contact time. A notable improvement in the gel strength of sonicated and heat coagulated dairy systems was also observed. When sonication was combined with a pre-heat treatment of 80 degrees C for 1 min or 85 degrees C for 30s, the heat stability of the dairy ingredients containing whey proteins was significantly improved. The effect of sonication was attributed mainly to physical forces generated through acoustic cavitation as supported by particle size reduction in response to sonication. As a result, the gelling properties and heat stability aspects of sonicated dairy ingredients were maintained after spray drying and reconstitution. Overall, the sonication procedure for processing dairy systems may be used to improve process efficiency, improve throughput and develop value added ingredients with the potential to deliver economical benefits to the dairy industry. PMID:19948420
Zisu, Bogdan; Bhaskaracharya, Raman; Kentish, Sandra; Ashokkumar, Muthupandian
In water-limited environments like the Sahel, rangelands function as strongly coupled ecological-hydrological systems. Rainfall and soil moisture availability are the main forces driving vegetation structure and composition, and vegetation exerts strong controls on the redistribution and infiltration of rainfall. The presence and duration of surface waters in the landscape, however, determines livestock access to and consumption of pasture resources, with feedbacks on vegetation structure and ecohydrology. In this study, we use the Tree Grass Vegetation Model (TGVM) to study the interactions between climate, vegetation, grazing and lake volume in the watersheds surrounding 260 ponds in the Sahel. Analyses focus on 4 regions (Southwestern Niger, Eastern Mali, Western Mali and Northern Senegal) representing a range of bioclimatic, edaphic and land use conditions and were performed during the period 1972-2011. Unsupervised land cover classification maps using Landsat time series data were used to provide soil information, assuming a strong correlation between vegetation type and the underlying soil type, and the curve number method was used to estimate runoff during rainfall. We will explore the socio-ecohydrological relationships in response to grazing disturbances and climate variability, and discuss how feedbacks mediated by anthropogenic control of herbivore density could be significant for the sustainable management of Sahelian and other dryland regions.
Kaptue, A.; Prihodko, L.; Hanan, N. P.
Cool-season annual forages provide high-quality herbage for up to 5 mo in the US Gulf Coast states, but their management in pasture-based dairy systems has received little attention. Objectives of this study were to evaluate pasture and animal responses when lactating Holstein cows (n=32, mean DIM=184±21) grazed either N-fertilized rye (Secale cereale L.)-annual ryegrass (Lolium multiflorum Lam.) mixed pastures or rye-annual ryegrass-crimson clover (Trifolium incarnatum L.)-red clover (Trifolium pratense L.) pastures at 2 stocking rates (5 vs. 2.5 cows/ha) and 2 rates of concentrate supplementation [0.29 or 0.40 kg of supplement (as is)/kg of daily milk production]. Two cows paired by parity (one multiparous and one primiparous) were assigned randomly to each pasture. The 2 × 2 × 2 factorial arrangement of treatments was replicated twice in a completely randomized design. Forage mixture and supplementation rate did not affect milk production during three 28-d periods. Greater milk production occurred at the low (19.7 kg/d) than the high (14.7 kg/d) stocking rate during periods 2 and 3, but production was similar during period 1. Despite lower production per cow, milk production per hectare was generally greater at the high stocking rate (81.6 vs. 49.5 kg/ha). Generally, greater pregraze herbage mass on pastures at the lower stocking rate (1,400 vs. 1,150 kg/ha) accounted for greater herbage allowance. Both forage (8.0 vs. 5.9 kg/d) and total (14.1 vs. 11.6) organic matter intake were greater at the low stocking rate. Cows fed less supplement had greater forage organic matter intake (8.0 vs. 6.1 kg/d). Greater herbage mass was associated with the greater intake and subsequent greater milk production. Differences in forage nutritive value, blood metabolites and milk composition, although showing some response to treatments, may not be of sufficient magnitude to affect choice of pasture species or other management practices. Animal performance was not improved by adding clovers to mixed cool-season grass pastures like those in this study. Stocking rate had a major effect on pasture and animal performance. During the cool season, supplementation with concentrates should be planned based on estimated energy intake from forages to achieve optimum milk production and ensure maintenance of body condition. PMID:21787931
Macoon, B; Sollenberger, L E; Staples, C R; Portier, K M; Fike, J H; Moore, J E
To assess the benefits of on-farm use of a computer- ized management information system (DairyMAN, Department of Veterinary Clinical Science, Massey University, Palmerston North, New Zealand) on seasonally calving herds of New Zealand, data for 144 herds using this system were compared with a strati- fied random sample of 294 herds using only the cen- tralized National Dairy Database system
D. P. Hayes; D. U. Pfeiffer; R. S. Morris
Sheep (Ovis aries L.) grazing during fallow is an effective method of controlling weeds and pests in the wheat (Triticum aestivum L.)-fallow system. Little is known about the effect of sheep grazing on dryland soil properties and wheat yield. We evaluated the effects of fallow management for weed co...
To investigate future tools for targeted selective treatment against gastrointestinal nematodes (GIN) in adult dairy cows, we evaluated herd and individual cow factors associated with the post-treatment milk production (MP) response over time. A field trial involving 20 pasturing dairy herds in Western France was conducted in autumn 2010 and autumn 2011. In each herd, lactating cows were randomly allocated to a treatment group (fenbendazole) (623 cows), or a control group (631 cows). Daily cow MP was recorded from 2 weeks before until 10 to 14 weeks after treatment. Individual serum anti-Ostertagia antibody levels (expressed as ODR), pepsinogen levels, faecal egg count (FEC), and bulk tank milk ODR were measured at the time of treatment. Moreover, in each herd, information regarding heifers' grazing and treatment history was collected to assess the Time of Effective Contact (TEC, expressed in months) with GIN infective larvae before the first calving. TEC was expected to reflect the development of immunity against GIN, and TEC=8 months was a cautious threshold over which the resistance to re-infection was expected to be established. Daily MP averaged by week was analyzed using linear mixed models with three nested random effects (cow within herd and herd within year). The overall treatment effect was significant but slight (maximum=+0.85 kg/d on week 6 after treatment), and the evolution of treated cows' MP differed significantly according to several factors. At the herd level, cows from low-TEC herds responded better than cows from high-TEC (? 8 months) herds; cows from herds in which the percentage of positive FEC was >22.6% (median value) responded better than those from herds where it was lower. At the individual cow level, primiparous cows, cows with days in milk (DIM) < or = 100 at the time of treatment, and cows with low individual ODR (< or = 0.38) responded better than multiparous cows, cows with DIM>100, and cows with higher ODR, respectively. These results highlight the variability of the treatment response, suggesting that whole herd anthelmintic treatment are not always appropriate, and propose promising key criteria for targeted selective treatment for GIN in dairy cows. Particularly, the TEC is an original criterion which lends support for a simultaneous on-farm qualitative analysis of grazing management factors. PMID:24468428
Ravinet, N; Bareille, N; Lehebel, A; Ponnau, A; Chartier, C; Chauvin, A
Six Holstein cows fitted with ruminal cannulae were used in two simultaneous 3 × 3 Latin squares to study the effects of protein supplements on ruminal fermenta- tion and in situ crude protein degradability. Cows rota- tionally grazed a winter oats (Avena sativa L.) pasture and were supplemented with one of three concentrate supplements: 1) low protein sunflower meal (L-SM);
F. Bargo; D. H. Rearte; F. J. Santini; L. D. Muller
Savannas occur across all of northern Australia and are extensively used as rangelands. A recent surge in live cattle exports to Southeast Asia has caused excessive grazing impacts in some areas, especially near watering points. An important ecological and management question is "how resilient are savanna ecosystems to grazing disturbances?" Resilience refers to the ability of an ecosystem to remain in its current state (resist change) and return to this state (recover) if disturbed. Resilience responses can be measured using field data. These responses can then be modelled to predict the likely resistance and recovery of savannas to grazing impacts occurring under different climatic conditions. Two approaches were used to model resilience responses. First, a relatively simple mathematical model based on a sigmoid response function was used. This model proved useful for comparing the relative resilience of different savanna ecosystems, but was limited to ecosystems and conditions for which data were available. Second, a complex process model, SAVANNA, was parameterised to simulate the structure and function of Australian savannas. Simulations were run for 50 years at two levels of grazing to evaluate resistance and then for another 50 years with no grazing to evaluate recovery. These runs predicted that savanna grasslands were more resistant to grazing (changed less) than red-loam woodlands, which recovered relatively slowly from grazing impacts. The SAVANNA model also predicted that these woodlands would recover slightly slower under the climate change scenario projected for northern Australia. PMID:11697665
Ludwig, J A; Coughenour, M B; Liedloff, A C; Dyer, R
A nonlinear analysis is performed to characterize the effects of a nonsmooth freeplay nonlinearity on the response of an aeroelastic system. This system consists of a plunging and pitching rigid airfoil supported by a linear spring in the plunge degree of freedom and a nonlinear spring in the pitch degree of freedom. The nonsmooth freeplay nonlinearity is associated with the pitch degree of freedom. The aerodynamic loads are modeled using the unsteady formulation. Linear analysis is first performed to determine the coupled damping and frequencies and the associated linear flutter speed. Then, a nonlinear analysis is performed to determine the effects of the size of the freeplay gap on the response of the aeroelastic system. To this end, two different sizes are considered. The results show that, for both considered freeplay gaps, there are two different transitions or sudden jumps in the system's response when varying the freestream velocity (below linear flutter speed) with the appearance and disappearance of quadratic nonlinearity induced by discontinuity. It is demonstrated that these sudden transitions are associated with a tangential contact between the trajectory and the freeplay boundaries (grazing bifurcation). At the first transition, it is demonstrated that increasing the freestream velocity is accompanied by the appearance of a superharmonic frequency of order 2 of the main oscillating frequency. At the second transition, the results show that an increase in the freestream velocity is followed by the disappearance of the superharmonic frequency of order 2 and a return to a simple periodic response (main oscillating frequency).
Vasconcellos, R.; Abdelkefi, A.; Hajj, M. R.; Marques, F. D.
Crop and grazing land management influences greenhouse gas emissions, which can be reduced by adopting conservation practices. Operators of cropland systems use a variety of practices that have implications for emissions, such as nutrient additions, irrigation, liming applications, tillage practices...
EFFECTS OF CATTLE GRAZING SYSTEMS ON SHRUB-GRASSLAND BIRDS IN SOUTH TEXAS A Thesis by DOUGLAS WAYNE SWANSON Submitted to the Office of Graduate Studies Texas A8 M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1988 Major Subject: Wildlife and Fisheries Sciences EFFECTS OF CATTLE GRAZING SYSTEMS ON SHRUB-GRASSLAND BIRDS IN SOUTH TEXAS A Thesis by DOUGLAS WAYNE SWANSON Approved as to style and content by: Lytle H. Bl kenship (Chairman...
Swanson, Douglas Wayne
The objective of this study was to investigate the effect of milking frequency (MF) at 2 feeding levels (FL) on milk production, body condition score, and metabolic indicators of energy status in grazing dairy cows during early lactation. Multiparous Holstein-Friesian and Holstein-Friesian × Jersey cows (n=120) grazed pasture and were milked twice daily (2×) from calving until 34 ± 6 d in milk (mean ± standard deviation). Cows were then allocated to 1 of 4 treatments in a 2 × 2 factorial arrangement. Treatments consisted of 2 FL: adequately fed [AF; 14.3 kg dry matter intake (DMI)/cow per d] or underfed (UF; 8.3 kg of DMI/cow per d) and 2 MF: 2× or once daily (1×). Treatments were imposed for 3 wk. After the treatment period, all cows were offered a generous pasture allowance (grazing residuals >1,600 kg of dry matter/ha) and milked 2×. During the 3-wk treatment period, we observed an interaction between FL and MF for energy-corrected milk (ECM), such that the decrease due to 1× milking was greater in AF than in UF cows (20 and 14% decrease, respectively). No interactions were found posttreatment. Cows previously UF produced 7% less ECM than AF cows during wk 4 to 12; however, no subsequent effect was observed of the previous underfeeding. Cows previously milked 1× produced 5% less ECM during wk 4 to 12, and differences remained during wk 13 to 23. During the 3-wk treatment period, UF cows lost 0.2 body condition score units (1-10 scale) and this was not affected by 1× milking. During the treatment period, UF cows had lower plasma glucose, insulin, and insulin-like growth factor I, and greater nonesterified fatty acids and ?-hydroxybutyrate concentrations than AF cows. Cows milked 1× had greater plasma glucose, insulin, and insulin-like growth factor I, and lower nonesterified fatty acids and ?-hydroxybutyrate concentrations compared with cows milked 2×. In conclusion, energy status was improved by 1× milking; however, when UF cows were milked 1×, milk production was reduced by more than underfeeding alone. The immediate and residual responses to 1× milking need to be considered when using this management strategy during a feed deficit. PMID:23891301
Kay, J K; Phyn, C V C; Rius, A G; Morgan, S R; Grala, T M; Roche, J R
Through an expansion of the Dairy Forage System Model (DAFOSYM), an Integrated Farm System Model was created to study the long-term performance, environmental impact, and economics of crop, beef and dairy production systems. Simulation of cash crop hay, cow calf, stocker and dairy production options...
A simple, compact bite counter was used to record dairy cow jaw movements. This information was used to estimate feed intake. The device is composed of a pendulum, a microcontroller, and a transmitter attached to a collar. The microcontroller memory can store the number of bites over 10-min intervals for up to 3 mo and has a battery life of more than 1 yr. The number of bites measured by personal observation, and the values reported by the counter were compared for 5 multiparous, nonlactating Holstein cows. The correlation was linear with an R(2) value of 0.9, unaffected by rumination, and little affected by walking. The collar system avoided the problems often experienced with counters attached to halters. The utility of the bite counter recordings in estimating intake was tested using 8 multiparous lactating cows. The slopes of the regression lines relating the number of bites to feed intake were dependent on the level of available pasture mass (120 or 190 g standing dry matter/m(2)). The feed intake could be estimated by applying linear regression to the number of bite counts versus pasture disappearance. In both cases the R(2) values of the regression lines were >0.7. Although the counter recorded jaw movements during grazing when the head was down, it did not record rumination or mastication when the head was raised because the counter/collar did not contact the jaw in this position. The bite counters were easy to attach to the cows using the collar and could be used effectively by farmers and researchers. PMID:19233793
Umemura, K; Wanaka, T; Ueno, T
Parasitic helminths present one of the most pervasive challenges to grazing herbivores. Many macro-parasite transmission models focus on host physiological defence strategies, omitting more complex interactions between hosts and their environments. This work represents the first model that integrates both the behavioural and physiological elements of gastro-intestinal nematode transmission dynamics in a managed grazing system. A spatially explicit, individual-based, stochastic model is developed, that incorporates both the hosts' immunological responses to parasitism, and key grazing behaviours including faecal avoidance. The results demonstrate that grazing behaviour affects both the timing and intensity of parasite outbreaks, through generating spatial heterogeneity in parasite risk and nutritional resources, and changing the timing of exposure to the parasites' free-living stages. The influence of grazing behaviour varies with the host-parasite combination, dependent on the development times of different parasite species and variations in host immune response. Our outputs include the counterintuitive finding that under certain conditions perceived parasite avoidance behaviours (faecal avoidance) can increase parasite risk, for certain host-parasite combinations. Through incorporating the two-way interaction between infection dynamics and grazing behaviour, the potential benefits of parasite-induced anorexia are also demonstrated. Hosts with phenotypic plasticity in grazing behaviour, that make grazing decisions dependent on current parasite burden, can reduce infection with minimal loss of intake over the grazing season. This paper explores how both host behaviours and immunity influence macro-parasite transmission in a spatially and temporally heterogeneous environment. The magnitude and timing of parasite outbreaks is influenced by host immunity and behaviour, and the interactions between them; the incorporation of both regulatory processes is required to fully understand transmission dynamics. Understanding of both physiological and behavioural defence strategies will aid the development of novel approaches for control. PMID:24223133
Fox, Naomi J; Marion, Glenn; Davidson, Ross S; White, Piran C L; Hutchings, Michael R
The aim of this study was to determine the effect of diet, energy balance and milk production on oxidative stress in early-lactating, Holstein-Friesian dairy cows fed to produce either low or high levels of milk. Indicators of energy balance (non-esterified fatty acids, ?-hydroxybutyrate, glucose and insulin-like growth factor-1) and indicators of oxidative stress (reactive oxygen metabolites and biological antioxidants) were measured in the first 5 weeks of lactation. Energy balance indicators showed that high producing animals had a lower degree of negative energy balance. Diet was found to have an indirect effect on the level of oxidative stress. Factors associated with a high level of oxidative stress were severe negative energy balance (mean -71 ± 6.85 27 MJ/cow/day, P < 0.05) and lower levels of milk production (mean 26.4 ± 0.07 28 L/cow/day, P < 0 .05). Further studies will be required to more precisely determine the specific effects of diet, energy balance and milk production on such stress in dairy cows and to establish normal ranges for these biomarkers. PMID:19804998
Pedernera, Mariana; Celi, Pietro; García, Sergio C; Salvin, Hannah E; Barchia, Idris; Fulkerson, William J
problems, many dairy men have installed mechanical separators includ ing static, vibrating, or rotating screens to remove fibrous material from the liquid waste stream before it enters the lagoons (Figure 7). Approxi mately 20 to 30 percent...-rate pumped flushillg are 1 to 3 percent slope and a flow-rate of 75 to 100 gpm per foot of channel width. Lagoon effluent recirculated for flushing may cause accelerated metal corrosion or crystalline deposits in pumps and pipelines. Plastic pipe...
Sweeten, John M.
We compared diurnal patterns of vaginal temperature in lactating cows under grazing conditions to evaluate genotype effects on body temperature regulation. Genotypes evaluated were Holstein, Jersey, Jersey × Holstein and Swedish Red × Holstein. The comparison of Holstein and Jersey versus Jersey × Holstein provided a test of whether heterosis effects body temperature regulation. Cows were fitted with intravaginal temperature recording devices that measured vaginal temperature every 15 min for 7 days. Vaginal temperature was affected by time of day ( P < 0.0001) and genotype × time ( P < 0.0001) regardless of whether days in milk and milk yield were used as covariates. Additional analyses indicated that the Swedish Red × Holstein had a different pattern of vaginal temperatures than the other three genotypes (Swedish Red × Holstein vs others × time; P < 0.0001) and that Holstein and Jersey had a different pattern than Jersey × Holstein [(Holstein + Jersey vs Jersey × Holstein) × time, P < 0.0001]. However, Holstein had a similar pattern to Jersey [(Holstein vs Jersey) × time, P > 0.10]. These genotype × time interactions reflect two effects. First, Swedish Red × Holstein had higher vaginal temperatures than the other genotypes in the late morning and afternoon but not after the evening milking. Secondly, Jersey × Holstein had lower vaginal temperatures than other genotypes in the late morning and afternoon and again in the late night and early morning. Results point out that there are effects of specific genotypes and evidence for heterosis on regulation of body temperature of lactating cows maintained under grazing conditions and suggest that genetic improvement for thermotolerance through breed choice or genetic selection is possible.
Dikmen, S.; Martins, L.; Pontes, E.; Hansen, P. J.
Automatic milking systems (AMS) offer dairy farmers relief from the time consuming and demanding routine of milking. This new technology is now reliable and practical for use on commercial farms, and it is widely used in northern Europe. Although this technology is beginning to be adopted in the USA...
The current market demand and price for organic milk is encouraging dairy producers, particularly those on smaller farms, to consider organic production as a means for improving the economic viability of their operations. Of particular interest in this region is a low-input production system relying...
Climate change is affecting the production of feed on dairy farms. Warming climates also affect the performance of dairy cattle and the interactions between feed production and animal performance. Process level simulation of dairy production systems provides a tool for whole-farm evaluation of the e...
Reproduction in grazing dairy cows treated with 14-day controlled internal drug release for presynchronization before timed artificial insemination compared with artificial insemination after observed estrus.
Progesterone-releasing (controlled internal drug release, CIDR) devices inserted for 14 d are used to presynchronize the estrous cycle for timed artificial insemination (TAI) in beef heifers (14-d CIDR-PGF(2?) program). The objective was to test a similar program in dairy cows by measuring first-service conception rates (FSCR), pregnancy rates after 2 AI, and time to pregnancy compared with a control (AI after observed estrus). Postpartum cows (Holstein, Jersey, or crossbred; n=1,363) from 4 grazing dairy farms were assigned to 1 of 2 programs: 14dCIDR_TAI [CIDR in for 14 d, CIDR out, PGF(2?) injection at 19 d after CIDR removal, GnRH injection 56 h later, and then TAI 16 h later; n=737] or control [AI after observed estrus; reproductive program with PGF(2?) (cycling cows) and CIDR (noncycling cows) to synchronize estrus with the start of the breeding season; n=626]. Body condition was scored (1 to 5; thin to fat) at the start of the trial. The interval from the start of the breeding period (final PGF(2?) injection of either program) to first AI was shorter for 14dCIDR_TAI compared with the control (3.0±0.2 vs. 5.3±0.2 d; mean ± SEM) but 14dCIDR_TAI cows had lesser FSCR than controls (48 vs. 61%). Farm affected FSCR (50, 51, 67, and 58% for farms 1 to 4). The BCS affected FSCR (50, 55, and 62% for BCS=2, 2.5, and 3, respectively). Cows that either calved the year before (carryover) or that calved early in the calving season had greater FSCR than cows that calved later in the calving season (55, 61, and 42%, respectively). The percentage of cows pregnant to AI (first and second inseminations within 31-d breeding season) was similar for 14dCIDR_TAI and control (64 vs. 70%) cows, but farm (64, 62, 80, and 69%) and time of calving (70, 76, and 56%: carryover, early, and late, respectively) affected the percentage. Survival analyses showed an initial advantage for 14dCIDR_TAI (more cows inseminated and more pregnancies achieved early in the breeding season) that was not maintained over time. Conclusions were that the 14dCIDR_TAI program achieved acceptable FSCR (48%) and overall AI pregnancy rates (64%), but did not surpass a control program that used AI after observed estrus (61 and 70%, respectively). PMID:23141825
Escalante, R C; Poock, S E; Mathew, D J; Martin, W R; Newsom, E M; Hamilton, S A; Pohler, K G; Lucy, M C
The objectives were to compare the effects of 2 methods of presynchronization and 2 lengths of proestrus on fertility of grazing dairy cows subjected to a 5-d timed artificial insemination (AI) protocol at initiation of breeding season. Lactating dairy cows (n=1,754) from 3 seasonal grazing farms were blocked within farm by breed, parity, and days in milk (DIM). Study d 0 was considered the day of AI of cows in COS72 (72h of proestrus). Within each block, cows were randomly assigned to 1 of 2 presynchronization treatments: a PGF(2?)-based program, Presynch, consisting of 2 injections of PGF(2?) administered on d -32 and -18, or a PGF(2?)-GnRH-based program, Double-Ovsynch (DO), consisting of GnRH on d -25, PGF(2?) on d -18, and GnRH on d -15. Within each of the 2 presynchronization treatments, cows were randomly assigned to 1 of 2 lengths of proestrus within the 5-d timed AI protocol, consisting of GnRH on d -8, PGF(2?) on d -3 and -2, and GnRH+AI at either 58 h (COS58) or 72 h (COS72) after the d -3 PGF(2?) injection. Ovaries were scanned by ultrasonography twice, on d -42 and -32, to determine estrous cyclicity before enrollment in the study. Blood was sampled and analyzed for concentrations of estradiol on the day of AI. Pregnancies per AI (P/AI) were determined 30 and 65 d after AI. Presynchronization did not affect the concentration of estradiol at AI (DO=6.4 vs. Presynch=5.8 pg/mL), detection of estrus at AI (20.8 vs. 25.9%), or P/AI on d 30 (56.8 vs. 59.1%) and 65 (52.5 vs. 52.4%) after the first AI. Cows receiving COS72 had increased concentration of estradiol (6.6 vs. 5.5 pg/mL) and detection of estrus at AI (28.5 vs. 10.8%) compared with cows receiving COS58. Length of proestrus did not affect P/AI on d 30 (COS72=58.7 vs. COS58=56.1%) but, in Presynch cows, COS58 was detrimental to fertility on d 65 after AI (54.9 vs. 46.5%). Pregnancy loss between gestational d 30 and 65 was greater for Presynch than for DO (7.6 vs. 11.3%), but it was not affected by length of proestrus. Estrous cyclic cows had greater P/AI than anovular cows on d 30 (61.7 vs. 35.1%) and 65 (56.1 vs. 30.7%), but no interaction between estrous cyclic status and treatments was detected. Crossbred Holstein/Jersey cows had superior fertility than their purebred counterparts during the breeding season. The Presynch and DO protocols resulted in similar fertility with no overall difference between the presynchronization methods; however, limiting the length of proestrus to 58 h reduced P/AI in the 5-d timed AI protocol when cows had their estrous cycle presynchronized with Presynch but not with DO. PMID:22541478
Ribeiro, E S; Monteiro, A P A; Lima, F S; Ayres, H; Bisinotto, R S; Favoreto, M; Greco, L F; Marsola, R S; Thatcher, W W; Santos, J E P
Forty-four early-lactation dairy cows of mixed parity were used to examine the effect of 4 supplemental concentrate types (n=11) on milk production and metabolic status. Animals were blocked by parity and calving date, and blocks were balanced for previous milk yield and milk protein yield. Cows received grazed pasture plus 5.17 kg of DM/d of 1 of the following isoenergetic (1.1 units of energy for lactation) concentrates: 1) high crude protein (CP) with rolled barley (HP, 19% CP); b) low CP with rolled barley (LP, 15% CP); c) low CP with barley and a supplemental methionine hydroxy analog (HMBi; LP + HMBi, 15% CP); and d) low CP with ground corn (LP-corn, 15% CP). Milk yield was recorded from d 1 to 100 postpartum, with weekly milk sampling, body weight, and body condition score (BCS) measurements. Blood and rumen sampling were conducted weekly from wk 2 to 6 postpartum. Milk yield was lower for cows in the LP treatment compared with those offered other concentrate types (25.2 vs. 27.5 ± 0.39 kg/d). Animals in the HP group had a higher milk yield than those in the LP + HMBi group (28.2 vs. 26.8 ± 0.39 kg/d). Milk fat yield was lower from animals in the LP-corn group compared with those in the LP + HMBi group (0.94 vs. 1.03 ± 0.03 kg/d). Milk protein yield was lower in the LP group compared with those in the HP group (0.88 vs. 0.97 ± 0.02 kg/d). Animal body weight, BCS, and BCS loss were not affected by concentrate type. However, nonesterified fatty acids were higher from animals in the HP group than for those in the LP + HMBi group (0.41 vs. 0.33 ± 0.03 mmol/L), and ?-hydroxy butyric acid was higher from animals in the HP group than for those in the other treatments (0.71 vs. 0.59 ± 0.03 mmol/L). Glucose was higher from animals in the LP-corn group than for those in the HP and LP groups (3.3 vs. 3.2 ± 0.05 mmol/L). Blood urea-N was higher from animals offered HP compared with those offered the other treatments (5.49.6 vs. 4.21 ± 0.44 mmol/L). However, rumen NH(3)-N and volatile fatty acid concentration in the rumen were not affected by supplemental concentrate type. Reducing supplemental concentrate CP reduced milk yield. However, milk fat production and energy-corrected milk were not different, reducing the likelihood of an improved energy balance or a more favorable blood metabolic profile in early-lactation dairy cows grazing perennial ryegrass. Offering HMBi with low-CP concentrates or replacing rolled barley with ground maize improves milk production relative to low-CP concentrates and metabolic status relative to high-CP concentrates. PMID:22818468
Whelan, S J; Pierce, K M; Flynn, B; Mulligan, F J
1990 Major Subject: Range Science BOTANICAL AND CHEMICAL CONDITION OF SHEEP DIEIS ON TN3 GRAZING SySTEMS IN THE ~ PIATEAU A 'Thesis Approved as to style and content by: Charles A. (Co-Chair of lo ttee) M. K (Co-Chair of Committee) J. E. Huston... ~) J. L. Schuster (Head of Department) Dec~ 1990 Botanical and Cecal ~ition of Sheep Diets on Two Grazing Systems on the ~ Plateau. (Decent' 1990) Cheryl Lee Robinson, B. S. , Angelo State University Co ? Chairs of Advisory Committee: Dr. Charles A...
Robinson, Cheryl Lee
The effects of feeding total mixed ration (TMR) or pasture forage from a perennial sward under a management intensive grazing (MIG) regimen on grain intake and enteric methane (EM) emission were measured using chambers. Chamber measurement of EM was compared with that of SF6 employed both within chamber and when cows grazed in the field. The impacts of the diet on farm gate greenhouse gas (GHG) emission were also postulated using the results of existing life cycle assessments. Emission of EM was measured in gas collection chambers in Spring and Fall. In Spring, pasture forage fiber quality was higher than that of the silage used in the TMR (47.5% v. 56.3% NDF; 24.3% v. 37.9% ADF). Higher forage quality from MIG subsequently resulted in 25% less grain use relative to TMR (0.24 v. 0.32 kg dry matter/kg milk) for MIG compared with TMR. The Fall forage fiber quality was still better, but the higher quality of MIG pasture was not as pronounced as that in Spring. Neither yield of fat-corrected milk (FCM) which averaged 28.3 kg/day, nor EM emission which averaged 18.9 g/kg dry matter intake (DMI) were significantly affected by diet in Spring. However, in the Fall, FCM from MIG (21.3 kg/day) was significantly lower than that from TMR (23.4 kg/day). Despite the differences in FCM yield, in terms of EM emission that averaged 21.9 g/kg DMI was not significantly different between the diets. In this study, grain requirement, but not EM, was a distinguishing feature of pasture and confinement systems. Considering the increased predicted GHG emissions arising from the production and use of grain needed to boost milk yield in confinement systems, EM intensity alone is a poor predictor of the potential impact of a dairy system on climate forcing. PMID:23896042
Fredeen, A; Juurlink, S; Main, M; Astatkie, T; Martin, R C
Satellite remote sensing can be used to assess grazing intensities and provide information on grassland management. A methodology was developed for quantifying the effects of grazing intensities (GI) using the normalized difference vegetation index (NDVI) obtained by the moderate resolution imaging spectroradiometer (MODIS) on-board the earth observing system (EOS) terra satellite. A combination of GPS (global positioning system) and GIS
Kensuke Kawamura; Tsuyoshi Akiyama; Hiro-omi Yokota; Michio Tsutsumi; Taisuke Yasuda; Osamu Watanabe; Shiping Wang
Sensor scientists have been successful in developing detectors for tiny concentrations of rare compounds, but the work is rarely applied in practice. Any but the most trivial application of sensors requires a specification that should include a sampling system, a sensor, a calibration system and a model of how the information is to be used to control the process of interest. The specification of the sensor system should ask the following questions. How will the material to be analysed be sampled? What decision can be made with the information available from a proposed sensor? This project provides a model of a systems approach to the implementation of automatic ovulation prediction in dairy cows. A healthy well managed dairy cow should calve every year to make the best use of forage. As most cows are inseminated artificially it is of vital importance mat cows are regularly monitored for signs of oestrus. The pressure on dairymen to manage more cows often leads to less time being available for observation of cows to detect oestrus. This, together with breeding and feeding for increased yields, has led to a reduction in reproductive performance. In the UK the typical dairy farmer could save € 12800 per year if ovulation could be predicted accurately. Research over a number of years has shown that regular analysis of milk samples with tests based on enzyme linked immunoassay (ELISA) can map the ovulation cycle. However, these tests require the farmer to implement a manually operated sampling and analysis procedure and the technique has not been widely taken up. The best potential method of achieving 98% specificity of prediction of ovulation is to adapt biosensor techniques to emulate the ELISA tests automatically in the milking system. An automated ovulation prediction system for dairy cows is specified. The system integrates a biosensor with automatic milk sampling and a herd management database. The biosensor is a screen printed carbon electrode system capable of measuring concentrations of progesterone in milk in the range 0.3-25 ng/ml. The system is operational in the laboratory is described here and will be working on a test farm in the near future to automatically predict the ovulation of dairy cows routinely.
Mottram, Toby; Hart, John; Pemberton, Roy
We began a study in fall 2000 on a Dothan sandy loam to develop a conservation tillage system for integrating cotton and peanut production with winter-annual grazing of stocker cattle. Winter forages and summer tillage were evaluated in a strip plot design with four replications. Winter pastures wer...
Grazing Strategies for Beef Production Escalating energy costs and alternative cropping systems with pasture-feedlot manage-Â· ment alternatives. Assess economic implications of beef production using an array character- istics of beef that may provide an alternative lean-to-fat composition for consum- ers. http
Increasing species richness of temperate pastures beyond one or two forage species could improve grazing system productivity. An ex- periment in western Illinois, USA, was initiated in August 2001 to test this idea. The main study objective was to determine how pastures sown with increasing levels of species richness would affect herbage yield and cow-calf performance. Three seed mixtures that
Benjamin F. Tracy; Dan B. Faulkner
The French West Indies and Caribbean authorities have the objective of increasing small ruminant production to match market demand and develop local economies. This paper highlights research results obtained in the French West Indies over the last 25 years in small ruminant farming. The accumulated knowledge enabled the design of an intensive grazing system whose main characteristics are: (i) three
M. Mahieu; H. Archimède; J. Fleury; N. Mandonnet; G. Alexandre
The present study was designed to evaluate how environmental factors in a dry-summer subtropical climate in Terceira-Azores (situated in the North Atlantic Ocean: 38° 43? N 27° 12? W) can affect dairy cow (Holstein) fertility, as well as seasonal influence on in vitro oocytes maturation and embryos development. Impact of heat shock (HS) effects on in vitro oocyte’s maturation and further embryo development after in vitro fertilization (IVF) was also evaluated. For such purpose the result of the first artificial insemination (AI) performed 60 to 90 days after calving of 6,300 cows were recorded for one year. In parallel, climatic data was obtained at different elevation points (n = 5) from 0 to 1,000 m and grazing points from 0 to 500 m, in Terceira island, and the temperature humidity index (THI) was calculated. For in vitro experiments, oocytes (n = 706) were collected weekly during all year, for meiotic maturation and IVF. Further, to evaluate HS effect, 891 oocytes were collected in the cold moths (December, January, February and March) and divided in three groups treated to HS for 24 h during in vitro maturation at: C (Control = 38.5°C), HS1 (39.5°C) and HS2 (40.5°C). Oocytes from each group were used for meiotic assessment and IVF. Cleavage, morula and blastocyst development were evaluated respectively on day 2, 6, and 9 after IVF. A negative correlation between cow’s conception rate (CR) and THI in grazing points (?91.3%; p<0.001) was observed. Mean THI in warmer months (June, July, August and September) was 71.7±0.7 and the CR (40.2±1.5%) while in cold months THI was 62.8±0.2 and CR was 63.8±0.4%. A similar impact was obtained with in vitro results in which nuclear maturation rate (NMR) ranged from 78.4% (±8.0) to 44.3% (±8.1), while embryos development ranged from 53.8% (±5.8) to 36.3% (±3.3) in cold and warmer months respectively. In vitro HS results showed a significant decline (p<0.05) on NMR of oocytes for every 1°C rising temperature (78.4±8.0, 21.7±3.1 and 8.9±2.2, respectively for C, HS1, and HS2). Similar results were observed in cleavage rate and embryo development, showing a clear correlation (96.9 p<0.05) between NMR and embryo development with respect to temperatures. Results clearly demonstrated that, up to a THI of 70.6, a decrease in the CR occurs in first AI after calving; this impairment was confirmed with in vitro results. PMID:25656191
Pavani, Krishna; Carvalhais, Isabel; Faheem, Marwa; Chaveiro, Antonio; Reis, Francisco Vieira; da Silva, Fernando Moreira
The present study was designed to evaluate how environmental factors in a dry-summer subtropical climate in Terceira-Azores (situated in the North Atlantic Ocean: 38° 43' N 27° 12' W) can affect dairy cow (Holstein) fertility, as well as seasonal influence on in vitro oocytes maturation and embryos development. Impact of heat shock (HS) effects on in vitro oocyte's maturation and further embryo development after in vitro fertilization (IVF) was also evaluated. For such purpose the result of the first artificial insemination (AI) performed 60 to 90 days after calving of 6,300 cows were recorded for one year. In parallel, climatic data was obtained at different elevation points (n = 5) from 0 to 1,000 m and grazing points from 0 to 500 m, in Terceira island, and the temperature humidity index (THI) was calculated. For in vitro experiments, oocytes (n = 706) were collected weekly during all year, for meiotic maturation and IVF. Further, to evaluate HS effect, 891 oocytes were collected in the cold moths (December, January, February and March) and divided in three groups treated to HS for 24 h during in vitro maturation at: C (Control = 38.5°C), HS1 (39.5°C) and HS2 (40.5°C). Oocytes from each group were used for meiotic assessment and IVF. Cleavage, morula and blastocyst development were evaluated respectively on day 2, 6, and 9 after IVF. A negative correlation between cow's conception rate (CR) and THI in grazing points (-91.3%; p<0.001) was observed. Mean THI in warmer months (June, July, August and September) was 71.7±0.7 and the CR (40.2±1.5%) while in cold months THI was 62.8±0.2 and CR was 63.8±0.4%. A similar impact was obtained with in vitro results in which nuclear maturation rate (NMR) ranged from 78.4% (±8.0) to 44.3% (±8.1), while embryos development ranged from 53.8% (±5.8) to 36.3% (±3.3) in cold and warmer months respectively. In vitro HS results showed a significant decline (p<0.05) on NMR of oocytes for every 1°C rising temperature (78.4±8.0, 21.7±3.1 and 8.9±2.2, respectively for C, HS1, and HS2). Similar results were observed in cleavage rate and embryo development, showing a clear correlation (96.9 p<0.05) between NMR and embryo development with respect to temperatures. Results clearly demonstrated that, up to a THI of 70.6, a decrease in the CR occurs in first AI after calving; this impairment was confirmed with in vitro results. PMID:25656191
Pavani, Krishna; Carvalhais, Isabel; Faheem, Marwa; Chaveiro, Antonio; Reis, Francisco Vieira; da Silva, Fernando Moreira
Ammonia (NH) emissions vary considerably among farms as influenced by climate and management. Because emission measurement is difficult and expensive, process-based models provide an alternative for estimating whole farm emissions. A model that simulates the processes of NH formation, speciation, aqueous-gas partitioning, and mass transfer was developed and incorporated in a whole farm simulation model (the Integrated Farm System Model). Farm sources included manure on the floor of the housing facility, manure in storage (if used), field-applied manure, and deposits on pasture (if grazing is used). In a comprehensive evaluation of the model, simulated daily, seasonal, and annual emissions compared well with data measured over 2 yr for five free stall barns and two manure storages on dairy farms in the eastern United States. In a further comparison with published data, simulated and measured barn emissions were similar over differing barn designs, protein feeding levels, and seasons of the year. Simulated emissions from manure storage were also highly correlated with published emission data across locations, seasons, and different storage covers. For field applied manure, the range in simulated annual emissions normally bounded reported mean values for different manure dry matter contents and application methods. Emissions from pastures measured in northern Europe across seasons and fertilization levels were also represented well by the model. After this evaluation, simulations of a representative dairy farm in Pennsylvania illustrated the effects of animal housing and manure management on whole farm emissions and their interactions with greenhouse gas emissions, nitrate leaching, production costs, and farm profitability. PMID:25603063
Rotz, C Alan; Montes, Felipe; Hafner, Sasha D; Heber, Albert J; Grant, Richard H
A 2 x 2 factorial study evaluated effects of cow wintering system and last trimester CP supplementation on performance of beef cows and steer progeny over a 3-yr period. Pregnant composite cows (Red Angus x Simmental) grazed winter range (WR; n = 4/yr) or corn residue (CR; n = 4/yr) during winter and within grazing treatment received 0.45 kg/d (DM) 28% CP cubes (PS; n = 4/yr) or no supplement (NS; n = 4/yr). Offspring steer calves entered the feedlot 14 d postweaning and were slaughtered 222 d later. Precalving BW was greater (P = 0.02) for PS than NS cows grazing WR, whereas precalving BCS was greater (P < 0.001) for cows grazing CR compared with WR. Calf birth BW was greater (P = 0.02) for CR than WR and tended to be greater (P = 0.11) for PS than NS cows. Prebreeding BW and BCS were greater (P
Larson, D M; Martin, J L; Adams, D C; Funston, R N
This document is a user manual for the Dairy Analytics and Nutrient Analysis (DANA) model. DANA provides an analysis of dairy anaerobic digestion technology and allows users to calculate biogas production, co-product valuation, capital costs, expenses, revenue and financial metrics, for user customizable scenarios, dairy and digester types. The model provides results for three anaerobic digester types; Covered Lagoons, Modified Plug Flow, and Complete Mix, and three main energy production technologies; electricity generation, renewable natural gas generation, and compressed natural gas generation. Additional options include different dairy types, bedding types, backend treatment type as well as numerous production, and economic parameters. DANA’s goal is to extend the National Market Value of Anaerobic Digester Products analysis (informa economics, 2012; Innovation Center, 2011) to include a greater and more flexible set of regional digester scenarios and to provide a modular framework for creation of a tool to support farmer and investor needs. Users can set up scenarios from combinations of existing parameters or add new parameters, run the model and view a variety of reports, charts and tables that are automatically produced and delivered over the web interface. DANA is based in the INL’s analysis architecture entitled Generalized Environment for Modeling Systems (GEMS) , which offers extensive collaboration, analysis, and integration opportunities and greatly speeds the ability construct highly scalable web delivered user-oriented decision tools. DANA’s approach uses server-based data processing and web-based user interfaces, rather a client-based spreadsheet approach. This offers a number of benefits over the client-based approach. Server processing and storage can scale up to handle a very large number of scenarios, so that analysis of county, even field level, across the whole U.S., can be performed. Server based databases allow dairy and digester parameters be held and managed in a single managed data repository, while allows users to customize standard values and perform individual analysis. Server-based calculations can be easily extended, versions and upgrades managed, and any changes are immediately available to all users. This user manual describes how to use and/or modify input database tables, run DANA, view and modify reports.
Sam Alessi; Dennis Keiser
Rangelands provide an opportunity to investigate the coupled feedbacks between human activities and natural ecosystems. These areas comprise at least one-third of the Earth's surface and provide ecological support for birds, insects, wildlife and agricultural animals including grazing lands for livestock. Capturing the interactions among water, carbon, and nitrogen cycles within the context of regional scale patterns of climate and management is important to understand interactions, responses, and feedbacks between rangeland systems and humans, as well as provide relevant information to stakeholders and policymakers. The overarching objective of this research is to understand the full consequences, intended and unintended, of human activities and climate over time in rangelands by incorporating dynamics related to rangeland management into an eco-hydrologic model that also incorporates biogeochemical and soil processes. Here we evaluate our model over ungrazed and grazed sites for different rangeland ecosystems. The Regional Hydro-ecologic Simulation System (RHESSys) is a process-based, watershed-scale model that couples water with carbon and nitrogen cycles. Climate, soil, vegetation, and management effects within the watershed are represented in a nested landscape hierarchy to account for heterogeneity and the lateral movement of water and nutrients. We incorporated a daily time-series of plant biomass loss from rangeland to represent grazing. The TRY Plant Trait Database was used to parameterize genera of shrubs and grasses in different rangeland types, such as tallgrass prairie, Intermountain West cold desert, and shortgrass steppe. In addition, other model parameters captured the reallocation of carbon and nutrients after grass defoliation. Initial simulations were conducted at the Curlew Valley site in northern Utah, a former International Geosphere-Biosphere Programme Desert Biome site. We found that grasses were most sensitive to model parameters affecting the daily-to-yearly ratio of net primary productivity allocation of carbon, non-structural carbohydrate pool, rate of root turnover, and leaf on/off days. We also ran RHESSys over AmeriFlux sites representing a spectrum of rangeland ecosystems, such as at Konza Prairie (Kansas), Fort Peck (Montana), and Corral Pocket (Utah), as well as grazed versus ungrazed sites. We evaluated RHESSys using net ecosystem exchange . Competition between rangeland vegetation types with different physiological parameters, such as carbon:nitrogen ratio and specific leaf area within a single site were also tested. Preliminary results indicated both species-specific parameters and allocation controls were important to capturing the ecosystem response to environmental conditions. Furthermore, the addition of a grazing component allowed us to better capture impacts of management at grazed sites. Future research will involve incorporation of other grazing processes, such as impacts of excreta and increased nutrient availability and cycling.
Reyes, J. J.; Liu, M.; Tague, C.; Choate, J. S.; Evans, R. D.; Johnson, K. A.; Adam, J. C.
Conclusions 26 26 26 31 36 36 38 40 41 45 47 50 54 54 55 57 57 58 APPENDIX A 60 APPENDIX B BIBLIOGRAPHY 75 90 LIST OF TABLES Table ~pa e 1. Grazing systems for pastures stocked at 25. 6 A. U. 's per section on the Texas Range Station.... Comparison of mean lamb production per A. U. as influenced by grazing management systems on the Texas Range Station. . 27 5b. Analysis of variance of mean lamb producti. on per A. U. as influenced by grazing management systems 27 5c. Duncan's multiple...
Allen, Jerry Vedder
Assessment of beef cow energy balance and efficiency in grazing-extensive rangelands has occurred on a nominal basis over short time intervals and has not accounted for the complexity of metabolic and digestive responses; behavioral adaptations to climatic, terrain, and vegetation variables; and documentation of the effects of nutrient form and supply to grazing cattle. Previous research using pen-fed cows demonstrated differences (P < 0.01) in efficiency of weight change ranging from 135 to 58 g/Mcal ME intake. Furthermore, variation in efficiency of ME use for tissue energy gain or loss ranged from 36% to 80%. In general, energy costs for maintenance, tissue accretion, and mobilization were greatest in Angus-based cows, intermediate in Brahman- and Hereford-based cows, and least in dairy-based cows. The most efficient cattle may reflect the types that are successful in semiarid grazing environments with low input management. Successful range cattle systems are likely the result of retention of animals that best adapted to the grazing environment and thus were potentially more efficient. Animals exposed to a variety of stressors may continually adapt, so energy expenditure is reduced and may tend to depart from the modeled beef cow in the 1996 NRC Beef Cattle Requirements. Critical factors comprising cow lifetime achievement, including reproductive success, disease resistance, and calf weaning weight, may be driven by cow total energy utilization in energy-limiting environments. Therefore, energy adjustments for adapted cattle within these landscapes and seasonal BW changes can alter seasonal NEm requirements. Evaluated studies indicate that in static grazing environments, NRC prediction fitness was improved compared with predictions from dynamic systems where cattle were influenced less by management and more by environmental conditions. Preliminary herd analyses cast doubt on the accuracy of NRC BCS descriptions representing NEm requirements of adapted females utilizing semiarid rangelands. Possible gaps are proposed that could be the basis for prediction inaccuracies. A more complete understanding of mechanisms contributing to productivity in the field than the current model predicts will improve future models to better simulate energetic accountability and subsequent female performance. PMID:24492551
Petersen, M K; Mueller, C J; Mulliniks, J T; Roberts, A J; DelCurto, T; Waterman, R C
In dairy cows, short-term changes of milking frequency in early lactation have been shown to produce an immediate and a long-term effect on milk yield in stall-fed cows. The effect is controlled locally within mammary glands and could be a function of either secretory mammary epithelial cell number or activity. To resolve this and determine its applicability in other feed management systems, a unilateral milking frequency experiment was conducted with udder halves of 17 multiparous, pasture-fed dairy cows milked either 4 times (4×) or once a day (1×) for 14d from 5±2d in milk. Mean half-udder milk yield during the treatment period was higher from the 4× compared with 1× udder halves and continued to be higher until 200d in milk once returned to twice a day milking. Mammary biopsies were obtained on d 14 of treatment from both udder halves of 10 cows. Proliferation of mammary cells was higher in 4× udder halves compared with 1×, whereas no difference in apoptosis levels was detected. Abundance of ?S1-casein, ?-casein, ?-lactalbumin, and ?-lactoglobulin mRNA was higher in tissue samples from 4× udder halves compared with 1×, whereas lactoferrin mRNA abundance was lower in 4× udder halves. In summary, change in milking frequency during early lactation affects proliferation of mammary cells as well as expression of the major milk protein genes, which both contribute to the observed changes in milk yield during and after unilateral milking frequency treatment. PMID:25465535
Murney, R; Stelwagen, K; Wheeler, T T; Margerison, J K; Singh, K
Microbial removal by a multi-component treatment system for dairy and municipal wastewater is being studied in Arizona, USA. The system consists of paired solids separators, anaerobic lagoons, aerobic ponds and constructed wetlands cells. The organisms under study include: total coliform, fecal coliform, enterovirus, Listeria monocytogenes, Clostridium perfringens, coliphage, Giardia lamblia and Cryptosporidium parvum. Organism removal rates from dairy wastewater varied
M. M. Karpiscak; L. R. Sanchez; R. J. Freitas; C. P. Gerba
As part of a research project on feasibility of loose housing systems in The Netherlands, financed by the Dutch Dairy Board (PZ) and Ministry of Agriculture, Nature and Food Quality (LNV), an international inventory on experiences with this kind of housing system for dairy cows took place. Data and experiences from Israël, United States of America, Germany, France and Ireland
Dooren van H. J. C; P. J. Galama
. By doing so, he will be helping both himself and the lending agency to provide his credit needs. Financing the Dairy System on a Central Blackland Farm CLARENCE A. MOORE and A. C. MAGEE* INTRODUCTION Texas agriculture has changed rapidly in recent... not be sufficient on some farms to pay the loan off in this limited time, but they may be forthcoming over a longer period. It is felt by some that this credit problem may exist because the lending agencies have not had sufficiently-reliable information about...
Moore, Clarence A.; Magee, A. C.
The effect of forward (F) and lateral (L) creep grazing, as two possible management alternatives of intensive production systems, on the gastro-intestinal nematode epidemiology of ewes and lambs was studied. Two groups of Romanov x Rasa Aragonesa ewes rearing twins and maintained on an autumn-contaminated pasture at a mean stocking density of 35 ewes ha-1, were used. Measurements were made of the population of infective larvae on the pasture, level of serum pepsinogen, worm eggs in faeces of ewes and lambs, and lambs' growth rate. In addition, post-mortem worm counts from 'indicator' lambs were used to establish the level of infection at each rotational grazing cycle. Two different waves of nematode infection were identified. In both treatments, the over-wintering larvae were responsible for the first outbreak of parasitism which was particularly important for lambs on Treatment F. The second wave of infection apparently came up with several overlapped L3 generations and had different effects on the animals of each group. While early pasture contamination was suffered by the lambs of Treatment F, lambs on Treatment L were not seriously affected until the end of the third grazing cycle (end of May). The different grazing behaviour of lambs in both treatments appeared to be related to the outbreak of parasitism in lambs. The general pattern of liveweight gains was similar for both groups of animals. However, during the first 90 days on pasture lamb growth rate under Treatment L (193 g day-1) was significantly higher than that under Treatment F (164 g day-1). The serum pepsinogen values, worm burdens and liveweight gains indicate that under intensive systems where lateral creep grazing is allowed for lambs, the level of parasite infection is maintained within acceptable limits for the first 90 days on pasture with lambs' growth rate close to their potential. However, the parasitic consequences of grazing under a forward creeping system indicate that anthelmintic drenchings should be used at lambing and at 3-week intervals thereafter during the first 42 days on pasture, after which the risk of contamination from the over-wintering population is over. PMID:2267726
Uriarte, J; Valderrábano, J
Chinese Americans have a high risk of osteoporosis and their calcium intake is substantially below the daily recommendation. However, little has been done to reduce the risk of this hard-to-reach population. This theory-based qualitative study explored how first-generation Chinese American couples with children view dairy products, how they use them in their family food system, and how these uses influence their dietary behavior or intake. Twenty couples, recruited from weekend Chinese schools at three locations in Pennsylvania, were interviewed. Taste, texture, and use of additives and growth hormones appeared to be more important influences on dairy choice than lactose intolerance. In these families, parental use of food rules and power to influence food patterns affected family flexibility about dairy use. Father's power, his views of dairy products, and his preference for Chinese-based dinners had a greater influence than those of his wife or children on the use of dairy-based dinner dishes. In contrast, choices at breakfast or lunch and for snacks were more flexible and could include dairy products. Nutrition educators can encourage introduction of dairy products into the traditional dietary pattern of Chinese Americans by offering opportunities to taste unfamiliar dairy products, demonstrating use of dairy products to prepare familiar foods, including both parents in any intervention or at least in tasting recipes, and providing information on importance of calcium to bone health and amount of calcium needed from reputable sources. PMID:20656096
Lv, Nan; Brown, J Lynne
A model system was developed for evaluating the efficacy of disinfectants for inactivating bacteria present in biofilms on surfaces within dairy factory environments. Mixed culture biofilms of six dairy factory isolates (pseudomonads, coliforms and presumptive staphylococci) were generated on factory floor tiles and subjected to up to three fouling and cleaning (FC) cycles. Disinfectants (hypochlorite, peroxyacetic acid-, acid anionic- and
G. C. Knight; H. M. Craven
The environmental loading of steroid hormones contained in dairy wastes may cause a potential adversely affect on the aquatic species. This work was to investigate the profile of steroid hormones in a typical dairy waste operation system and assess the potential risk of hormone contaminations result...
Cropping systems were once wholly integrated with livestock production, but today, few cropping systems include livestock. Sheep and goats traditionally produced on rangelands or pasture forages and supplemented with harvested feeds during winter. We present concepts and specific areas whereby gra...
Differences in sward structure influence intake by grazing cattle. Our objective was to determine relationships between dry matter intake (DMI) and sward characteristics of four diverse temperate grasses grazed by dairy heifers. Meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], orchardgrass (...
The impact of grazing experiences early in life on grazing behavior and performance of lactating dairy heifers was evaluated in a 3-year study. Sixty-four Holstein and Holstein x Jersey calves were randomly assigned to one of 4 treatments (n = 16) in 2008. Treatments were combinations of managing he...
Gene-flow methodology was used to calculate the cumulative discounted expressions (CDE) for annual\\/lactation, replacement heifer, cull cow, birth, yearling, and slaughter traits in alternative cattle production systems. Generic equations were presented and parameters representing dairy-beef production systems in Ireland and Brazil were inputted. Cumulative discounted expressions using input parameters from a hypothetical purebred dairy production system with poor cow longevity
D. P. Berry; F. E. Madalena; A. R. Cromie; P. R. Amer
Dairy production systems are an important global contributor to anthropogenic greenhouse gas (GHG) emissions including methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). Due to the role GHG play in climate ...
Ross, Stephen Alexander
Effects of feeding supplements which contained ground sunflower seeds in a pelleted versus non-pelleted concentrate treated with, or without, 50g\\/kg lignosulfonate were evaluated in 8 multiparous Holstein cows under grazing conditions. Cows were assigned to a double 4×4 Latin square design experiment with four 21d experimental periods. Whole diet total tract apparent digestibility, dry matter (DM) intake, milk production, milk
W. B. R. dos Santos; G. T. D. Santos; D. C. da Silva-Kazama; U. Cecato; F. E. de Marchi; J. V. Visentainer; H. V. Petit
Phytoplankton growing at the surface of lakes and oceans are removed from the water column by gravitational sedimentation and/or zooplankton grazing. Both of these processes are influenced by the aggregation state of the phytoplankton, which, in turn, may be altered through particle-particle coagulation. In this study, we present a mathematical analysis of these phenomena in an attempt to better understand the physical and biological factors that control phytoplankton concentrations in aquatic systems. During phytoplankton blooms, grazer concentrations are relatively low, the concentration of phytoplankton in the mixed layer is high, and phytoplankton production at the surface is countered by coagulation and sedimentation. In this case, dynamic scaling theory indicates that the concentration of total phytoplankton aggregates N0 and the volume fraction of phytoplankton N1 should decay as power laws of depth z: N0 ? z-? and N1 ? z-?. The values of the power law exponents ? and ? are determined by the physical and chemical processes responsible for coagulation and sedimentation in a given system. Under nonbloom conditions, the concentration of grazers is relatively high, the phytoplankton concentrations are relatively low, and phytoplankton generated at the surface are quickly transferred to higher-trophic levels by grazing. In this case, N0 and N1 decay with depth in an approximately exponential fashion. These results suggest that the principle mechanism by which phytoplankton are removed from the water column in natural aquatic systems may be differentiated by the depth evolution of N0 and N1.
Boehm, Alexandria B.; Grant, Stanley B.
The adaptation of the liver to periods of negative energy balance is largely unknown in beef cattle on grazing systems. We evaluated liver transcriptome throughout gestation and early lactation of purebred and crossbred beef cows [Angus, Hereford, and their F1 crossbreeds (CR)], grazing high or low herbage allowances (HA) of native grasslands (4 and 2.5 kg dry matter/kg body wt annual mean; n = 16) using an Agilent 4 × 44k bovine array. A total of 4,661 transcripts were affected by days [272 ? 2.5-fold difference, false discovery rate (FDR) ? 0.10] and 47 pathways were altered during winter gestation (-165 to -15 days relative to calving), when cows experienced decreased body condition score, decreased insulin, and increased nonesterified fatty acid concentrations. Gluconeogenesis and fatty acid oxidation pathways were upregulated, while cell growth, DNA replication, and transcription pathways were downregulated (FDR ? 0.25). We observed only small changes in the liver transcriptome during early lactation (+15 to +60 days). A total of 225 genes were differentially expressed (47 ? 2-fold difference, FDR ? 0.10) between HA. The majority of those were related to glucose and pyruvate metabolism and were upregulated in high HA, reflecting their better metabolic status. Two genes were upregulated in CR cows, but 148 transcripts (74 ? 2-fold change difference, FDR ? 0.10) were affected by the HA and cow genotype interaction. The transcriptional changes observed indicated a complex and previously unrecognized, hepatic adaptive program of grazing beef cows in different nutritional environments. Novel target candidate genes, metabolic pathways, and regulatory mechanisms were reported. PMID:24326346
Laporta, Jimena; Rosa, Guilherme J M; Naya, Hugo; Carriquiry, Mariana
Minimising surface water pollution resulting from farm?dairy effluent application to mole?pipe drained soils. II. The contribution of preferential flow of effluent to whole?farm pollutant losses in subsurface drainage from a West Otago dairy farm
To evaluate the role of artificial drainage systems in the transfer of nutrients and faecal organisms from soil to waterways, mole?pipe drainage flows were monitored from two large (27 × 40 m), hydrologically isolated field plots that were part of a long?term dairy pasture in West Otago, New Zealand. One plot was grazed only whilst the other plot was spray
R. M. Monaghan; L. C. Smith
of the requirement for the degree of YASTER OF SCIENCE Nay 1980 Major Subject: Pange Science EFFECTS OF' A SHORT DURATION GRAZING SYSTEM ON WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) IN THE RIO GRANDE PLAIN, TEXAS A Thesis by KEVIN LEIGH ALLRED Approved...EF'FECTS OF A SHCRT DURATION GRAZING SYSIKN ON WHITE-TAILED DEER (ODOCOILEUS VZRGINIANUS) ZN THE RIO GRANDE PLAIN, TEXAS A Thesis by VIN LEIGH ALLRED Submitted to the Graduate College of Texas AdH University in partial fulfillment...
Allred, Kevin Leigh
The effects of potential changes in United States beef production on global grazing systems and greenhouse gas emissions Jerome Dumortier1 , Dermot J Hayes2 , Miguel Carriquiry2 , Fengxia Dong3 , Xiaodong spillover effects on forestry and vice versa. Hence, the implementation of large-scale agricultural policies
Methods to estimate intake in grazing livestock include using markers, visual observation, mechanical sensors that respond to jaw movement and acoustic recording. In most of the acoustic monitoring studies, the microphone is inverted on the forehead of the grazing livestock and the skull is utilize...
Grazing lands in the northern Great Plains of North America are extensive, occupying over 50 Mha. Yet grazing land contributions to, or mitigation of, global warming potential (GWP) is largely unknown for the region. The objective of this study was to estimate GWP for three long-term (70 to 90 yr)...
Grazing management can affect grassland carbon (C) dynamics, yet limited information is available documenting management effects on soil carbon dioxide (CO2) efflux. A study was conducted to quantify the role of long-term grazing management to affect soil CO2 efflux within the semiarid northern Gre...
Sheep grazing to control weeds during fallow may influence greenhouse gas (GHG) emissions by consuming crop residue and returning feces and urine to the soil. We evaluated the effect of sheep grazing compared to herbicide application for weed control on soil temperature and water content at the 0- t...
Evaluating Technologies for Reducing Nutrients in Dairy Effluent The Geotube® Dewatering System in the North Bosque and Leon River Watersheds. In 2005, they evaluated the Geotube® de-watering system The Geotube® dewatering system was demonstrated by the Miratech Division of Ten Cate Nicolon and General
The current market demand and price for organic milk is encouraging dairy producers, particularly those on smaller farms, to consider organic production as a means for improving long-term economic sustainability. Extensive production information was collected from four case-study organic farms throu...
Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production. One hundred and eighty mixed age, primiparous and multiparous Holstein-Friesian/Illawarra cows were randomly assigned to two treatment groups (n = 90/group) with a 2×2 Latin square design. Each group was either offered treatments of kikuyu grass (Pennisetum clandestinum Hoach ex Chiov.) pasture (pasture) or soybean from 0900 h to 1500 h during the experimental period which consisted of 2 periods of 3 days following 5 days of training and adaptation in each period with groups crossing over treatments after the first period. The number of cows trafficking to each treatment was similar together with milk yield (mean ?18 L/cow/d) in this experiment. For the cows that arrived at soybean or pasture there were significant differences in their behaviour and consequently the number of cows exiting each treatment paddock. There was greater cow traffic (more cows and sooner) exiting pasture allocations. Cows that arrived at soybean stayed on the allocation for 25% more time and ate more forage (8.5 kg/cow/d/allocation) relative to pasture (4.7 kg/cow/d/allocation). Pasture cows predominantly replaced eating time with rumination. These findings suggest that replacing pasture with alternative grazeable forages provides no additional incentive to increase voluntary cow traffic to an allocation of feed in AMS. This work highlights the opportunity to increase forage intakes in AMS through the incorporation of alternative forages. PMID:25049970
Clark, C. E. F.; Horadagoda, A.; Kerrisk, K. L.; Scott, V.; Islam, M. R.; Kaur, R.; Garcia, S. C.
This study investigated the immediate and long-term effects of temporary alterations to postpartum milking frequency (MF) on milk production, body condition score (BCS), and indicators of energy status in pasture-grazed cows supplemented with concentrates. Multiparous Holstein-Friesian cows (n = 150) were randomly assigned to 1 of 5 groups at calving: milked twice daily (2 ×) throughout lactation (control), or milked either once daily (1 ×) or 3 times daily (3 ×) for 3 or 6 wk immediately postpartum, and then 2 × for the remainder of lactation. During wk 1 to 3 postpartum, cows milked 1 × produced 15% less milk and 17% less energy-corrected milk (ECM) than cows milked 2 ×. This immediate production loss increased to 20% less milk and 22% less ECM during wk 4 to 6 postpartum for cows that remained on 1 × milking; these animals also produced less than 1 × cows switched to 2 × milking after 3 wk. During wk 8 to 32, when all cows were milked 2 ×, those previously milked 1 × had sustained reductions in milk (-6%) and ECM (-8%) yields, which were not affected by the duration of reduced postpartum MF. In contrast, cows milked 3 × postpartum had 7% greater milk yields during wk 1 to 6 compared with 2 × controls, irrespective of the duration of increased MF. Milk yields also remained numerically greater (+5%) during wk 8 to 32 in cows previously milked 3 ×. Nevertheless, yields of ECM were not increased by 3 × milking, because of lower milk fat and protein contents that persisted for the rest of lactation. In addition, indicators of cow energy status reflected an increasing state of negative energy balance with increasing MF. Cows milked 1 × postpartum had greater plasma glucose and lower plasma nonesterified fatty acid concentrations during the reduced MF, and plasma glucose remained lower for 2 wk after cows had switched to 2 × milking. Moreover, BCS was improved relative to 2 × controls from wk 5 to 6. In contrast, cows milked 3 × had lower plasma glucose concentrations, greater plasma nonesterified fatty acid concentrations, and greater BCS loss during wk 1 to 3; however, greater body fat mobilization was not sustained, indicating that additional energy supplements may be required to achieve better milk production responses. In conclusion, temporary 1 × milking had lactation-long negative effects on milk and milk component yields but improved cow energy status and BCS, whereas temporary 3 × milking immediately increased milk yield but did not improve milk fat and protein yields in pasture-grazed cows. PMID:25200777
Phyn, C V C; Kay, J K; Rius, A G; Morgan, S R; Roach, C G; Grala, T M; Roche, J R
A scoring system with 1 to 5 scale was devised to measure body condition of dairy cows at any point during the lactation cycle. Cows were scored on appearance and palpation of back and hind quarters only. Relationships of body weight, frame size measurements, milk production, and characteristics related to the body condition scoring system were determined. During 18 too,
E. E. Wildman; G. M. Jones; P. E. Wagner; R. L. Boman; H. F. Troutt Jr.; T. N. Lesch
The performance of temperature-phased anaerobic digestion (TPAD) system in the stabilization of dairy cattle wastes at high solids concentrations has never been evaluated, though the process has been established as a feasible alternative to conventional mesophilic processes for the treatment of municipal wastewater sludges. In this study, the TPAD system operating at a retention time of 14 days was subjected
Shihwu Sung; Harikishan Santha
High-quality colostrum is an important factor influencing neonatal calf health, and quality assessment is essential to obtain good health results. This research evaluated the effects of the calf's sex, the parity of the cow and the hour of colostrum harvest after parity on the fat, nonfat solids, protein and Ig contents in Holstein colostrum for cows under high grazing conditions in the tropics. The effects of the calf's sex and parity on somatic cell count (SCC) at the first milking postpartum were determined. A comparison was made between a laboratory method and a farm method for the estimation of the fat and protein content of colostrum. Thirty-three cows were sampled in the study. The calf's sex was shown to have an effect on the amount of colostrum, on the concentration of fat, and on the amount of milk produced by lactating Holstein cows; all were higher in cows that gave birth to a female calf. Colostrum protein decreased after the first hour postpartum, and the Ig concentration had a tendency to decrease after 4 h. The cows that had parity 1-2 had lower Ig concentrations and total production of Igs, and higher SCC at the first milking postpartum. Ekomilk was a reliable method to measure the colostrum fat on the farm. PMID:25708565
Angulo, Joaquin; Gómez, Luis Miguel; Mahecha, Liliana; Mejía, Estefanía; Henao, Javier; Mesa, Carolina
Short communication: presynchronization for timed artificial insemination in grazing dairy cows by using progesterone for 14 days with or without prostaglandin F2? at the time of progesterone withdrawal.
Progesterone-containing devices can be inserted intravaginally for 14 d to presynchronize the estrous cycle for timed artificial insemination (TAI) in beef heifers ("14-day CIDR-PG" or "Show-Me-Synch" program). The progesterone treatment is effective for presynchronization because cattle develop a persistent dominant follicle during treatment that ovulates within 3 d after progesterone removal. The subsequent estrous cycle can be effectively used for a TAI program. Some cattle will retain a functional corpus luteum (CL) for the entire 14-d treatment period and will not be synchronized effectively because the interval to ovulation depends on the lifespan of their existing CL. The objective was to test the effect of a luteolytic dose of PGF(2?) at progesterone removal for improving synchrony of estrus after treatment and increasing conception rate to a subsequent TAI in dairy cows. Postpartum cows (n = 1,021) from 2 grazing dairy herds were assigned to 1 of 2 presynchronization programs that used a controlled internal drug releasing (CIDR) device containing progesterone: 14dCIDR (CIDR in, 14 d, CIDR out; n = 523) or 14dCIDR+PGF(2?) (CIDR in, 14 d, CIDR out, and PGF(2?); n = 498). Cows were body condition scored (BCS; 1 to 5, thin to fat) and tail painted at CIDR removal. Paint score (PS) was recorded after CIDR removal [PS = 0 (all paint removed, indication of estrus), PS = 3 (paint partially removed), or PS = 5 (no paint removed; indication of no estrus)]. At 19 d after CIDR removal, all cows were treated with PGF(2?), 56 h later treated with GnRH, and then 16 h later were TAI. Treating cows with PGF(2?) at CIDR removal increased the percentage with PS = 0 within 5 d (58.1% vs. 68.9%; 14dCIDR vs. 14dCIDR+PGF(2?)). We found no effect of treatment, however, on conception rate at TAI (41.1% vs. 43.6%; respectively). The TAI conception rate increased with increasing BCS and was greater for cows that had PS = 0 within 5 d after CIDR removal. In summary, treating cows with PGF(2?) at CIDR removal increased the percentage of cows with all tail paint removed but did not increase percentage of pregnant cows after TAI. PMID:22916915
Escalante, R C; Poock, S E; Mathew, D J; Martin, W R; Newsom, E M; Hamilton, S A; Pohler, K G; Lucy, M C
To improve cow management in large dairy herds, sensors have been developed that can measure physiological, behavioral, and production indicators on individual cows. Recently, the number of dairy farms using sensor systems has increased. It is not known, however, to what extent sensor systems are used on dairy farms, and the reasons why farmers invest or not in sensor systems are unclear. The first objective of this study was to give an overview of the sensor systems currently used in the Netherlands. The second objective was to investigate the reasons for investing or not investing in sensor systems. The third objective was to characterize farms with and without sensor systems. A survey was developed to investigate first, the reasons for investing or not in sensor systems and, then, how the sensor systems are used in daily cow management. The survey was sent to 1,672 Dutch dairy farmers. The final data set consisted of 512 dairy farms (response rate of 30.6%); 202 farms indicated that they had sensor systems and 310 farms indicated that they did not have sensor systems. A wide variety of sensor systems was used on Dutch dairy farms; those for mastitis detection and estrus detection were the most-used sensor systems. The use of sensor systems was different for farms using an automatic milking system (AMS) and a conventional milking system (CMS). Reasons for investing were different for different sensor systems. For sensor systems attached to the AMS, the farmers made no conscious decision to invest: they answered that the sensors were standard in the AMS or were bought for reduced cost with the AMS. The main reasons for investing in estrus detection sensor systems were improving detection rates, gaining insights into the fertility level of the herd, improving profitability of the farm, and reducing labor. Main reasons for not investing in sensor systems were economically related. It was very difficult to characterize farms with and without sensor systems. Farms with CMS and sensor systems had more cows than CMS farms without sensor systems. Furthermore, farms with sensor systems had fewer labor hours per cow compared with farms without sensor systems. Other farm characteristics (age of the farmer, availability of a successor, growth in herd size, milk production per cow, number of cows per hectare, and milk production per hectare) did not differ for farms with and without sensor systems. PMID:25465556
Steeneveld, W; Hogeveen, H
"oritioal" level whereby livestock produotion declines. Sharrow and Kr ueger (1979) reported that when stocking rates were equal, livestook seasonal weight gains were equal of cattle grazing ryegrass (Lolium sp, ) pastures. Likewise, Jung et al. ( 1985...
McKown, Charles David
The discussion about the impact of pastoral systems on ecosystems has been profoundly shaped by Hardin’s “tragedy of the commons”\\u000a argument that held pastoralists responsible for overgrazing the range. Recent studies have shown that grazing ecosystems are\\u000a much more complex and dynamic than was previously assumed and that pastoralists adaptively manage these systems. However,\\u000a we still have little understanding how
Mark Moritz; Eric Soma; Paul Scholte; Ningchuan Xiao; Leah Taylor; Todd Juran; Saïdou Kari
Over a 3-year period, the effect of differing N-application regimes on soil extractable-P concentration, soil phosphatase activity, and forage P uptake in a P-enriched grazed-pasture system was investigated. In the fall of each year, six 0.28-ha plots were overseeded with triticale ( × Triticosecale rimpaui Wittm.) and crimson clover (Trifolium incarnatum) into a tall fescue (Lolium arundinacea)/bermudagrass (Cynodon dactylon) sod and assigned to 1 of 3 N-fertilizer treatments (n = 2): 100% of N recommendation in a split application (100N), 50% in a single application (50N), and 0% of N recommendation (0N) for triticale. Cattle commenced grazing the following spring and grazed until May. In the summer, plots were overseeded with cowpea (Vigna unguiculata), fertilized at the same rates by reference to N recommendations for bermudagrass, and grazed by cattle until September. There were no effects of N fertilization on soil phosphatase activity, electrical conductivity, or concentrations of water-soluble P. Concentrations of extractable P decreased in plots receiving 50N, but increasing N fertilization to 100N resulted in no further reduction in extractable P. Forage biomass, foliar P concentrations, and forage P mass were not affected by N fertilization rates at the plant-community level, but responses were observed within individual forage species. Results are interpreted to mean that N fertilization at 50% of the agronomic recommendation for the grass component can increase forage P mass of specific forages and decrease soil extractable P, thus providing opportunity for decreasing P losses from grazed pasture. PMID:25728918
Dillard, Sandra Leanne; Wood, Charles Wesley; Wood, Brenda Hall; Feng, Yucheng; Owsley, Walter Frank; Muntifering, Russell Brian
Livestock production has been challenged as a large contributor to climate change, and carbon footprint has become a widely used measure of cattle environmental impact. This analysis of fifteen beef grazing systems in Uruguay quantifies the range of variation of carbon footprint, and the trade-offs with other relevant environmental variables, using a partial life cycle assessment (LCA) methodology. Using carbon footprint as the primary environmental indicator has several limitations: different metrics (GWP vs. GTP) may lead to different conclusions, carbon sequestration from soils may drastically affect the results, and systems with lower carbon footprint may have higher energy use, soil erosion, nutrient imbalance, pesticide ecotoxicity, and impact on biodiversity. A multidimensional assessment of sustainability of meat production is therefore needed to inform decision makers. There is great potential to improve grazing livestock systems productivity while reducing carbon footprint and other environmental impacts, and conserving biodiversity. PMID:25048094
Picasso, Valentín D; Modernel, Pablo D; Becoña, Gonzalo; Salvo, Lucía; Gutiérrez, Lucía; Astigarraga, Laura
A simple interferometric method capable of displaying quantitatively the wave front aberration of any image-forming optical system is described. Its application for testing and aligning grazing incidence reflection optics at the same conjugates as those of short-wavelength use is demonstrated. The image-forming wave front from the system being tested is compared with a true spherical wave front generated within the interferometer from a point at the intended focus. The differences are displayed as a fringe pattern superimposed on an image of the exit pupil. Each fringe corresponds to one wavelength of separation between the actual image-forming wave front and the Gaussian reference sphere. The principle originates from a paper by W. P. Linnik published in Russian and German in 1933. A translation is included as an appendix. Four variations on Linnik's design are discussed, one of which avoids the use of transmitting optics and normal incidence reflections altogether and could therefore be used at ultraviolet or soft x-ray wavelengths. PMID:20212593
Speer, R J; Chrisp, M; Turner, D; Mrowka, S; Tregidgo, K
Electricity use and costs were evaluated for a dairy farm using a water flush disposal system. Electricity conservastion, reducing the peak electrical demand, and alternative energy production from animal waste can be reduce purchased electrical costs while still maintaining the benefits derived from mechanization. ref.
M. D. Erdman; W. L. Bryan; J. C. Jr. Johnson; G. L. Newton
The aim of this work was to study the effect of two different kid-rearing systems, natural or artificial, on milk yield, composition, hygiene-sanitary quality, kid growth and cost in Florida dairy goats. Two groups of animals were created, one with goats under natural suckling and the other under artificial rearing. In the suckling group, the kids were suckled up to
M. Delgado-Pertíñez; J. L. Guzmán-Guerrero; Y. Mena; J. M. Castel; P. González-Redondo; F. P. Caravaca
Six options for anaerobic digestion of animal manure on mid-sized dairy farms in Minnesota have been presented to provide dairy farm operators with information needed to make decisions about odor control and manure management technology. Information for each option is presented with schematics of the system, an explanation of how the system functions, the environmental benefits and lessons learned from other similar digesters. Capital costs for the installation of the digesters and yearly costs are presented. The expected benefits from odor control and use of separated solids are presented for a 100-cow dairy. Scale up information for 200-cow and 300-cow dairies are included as a multiplier factor. There are also answers to the questions “who should consider a system like this? ” and “why would a farmer install this digester? ” Resources are provided with who to contact about similar digesters and additional references relevant to each design. The generation of energy is discussed in a separate section. The six options applied to mid-sized farms do not produce excess energy beyond the energy needed to heat the digester during the winter months. Adding capacity and electrical generators would be an upgrade to the digester after experience was gained with the digestion system.
Large-scale spatial patterns, whether in the height, density, or species composition of vegetation, are one of the most demonstrable and widely recognised features of heterogeneity in large herbivore grazing systems. But to understand how their existence relates to grazing processes, and what the implications of the patterns are for plants, animals, and for land users, requires adding spatial concepts, and
Anthony J. PARSONSa; Bertrand Dumont
The pattern of odd- and branched-chain fatty acids (OBCFA) in milk fat reflects rumen microbial activity and proportions of different rumen microbial groups. Therefore, these milk fatty acids (FA) are used to predict rumen proportions of volatile fatty acids, duodenal flow of microbial protein, and occurrence of rumen acidosis. However, current models do not correct for the potential effects of lactation stage on the level of OBCFA in milk fat. Hence, the objectives of this study were 1) to describe progressive changes related to lactation stage in concentrations of milk FA, with emphasis on the OBCFA, using the incomplete gamma function of Wood, and 2) to analyze whether lactation curves of milk FA on the one hand and milk production or milk fat content on the other hand coincide through evaluation of the correlation between the parameters of the Wood functions fitted to individual animal data. Data were collected from 2 trials in which milk FA during lactation were monitored. The first experiment was a stable trial with 2 groups of 10 cows receiving 2 dietary treatments from wk 1 to 40 of lactation. The second experiment was a grazing trial with 9 cows that were followed during the first 18 wk of lactation. Lactation curves of milk production, milk fat content, and individual milk FA were developed using the incomplete gamma function of Wood for each of the 3 dietary strategies separately. For almost all of the milk FA, lactation curve shapes were similar for all 3 dietary treatments. The OBCFA with chain lengths of 14 and 15 carbon atoms followed the lactation curves of the short- and medium-chain milk FA, which increased in early lactation. The OBCFA with chain length of 17 carbon atoms decreased during the early lactation period, following the pattern of milk long-chain fatty acids. The short- and medium-chain milk FA and OBCFA in the early lactation period seemed to be negatively correlated with the starting milk production and milk fat content, but correlations were modest. Information of milk FA lactation curves should be incorporated in predictive and classification models based on these milk FA, to improve their performance. PMID:18565925
Craninx, M; Steen, A; Van Laar, H; Van Nespen, T; Martín-Tereso, J; De Baets, B; Fievez, V
To find out if a depleted riparian system in the sagebrush steppe of eastern Oregon would respond quickly to improved management, five management treatments were applied for 7 years, ranging from ungrazed to heavily grazed treatments, including, in some cases, planting of woody species. While the results varied, all treatments were too limited to significantly restore the damaged areas within the 7-year span. Although some improvements were made in woody plant densities, little meaningful change occurred in the frequencies of herbaceous wetland plants, densities of small wildlife, or stream channel morphology. We concluded the restoration would take many years, possibly decades, without increased revegetation efforts and continued reductions in grazing in this riparian system damaged over 150 years.
Clary, W.P.; Shaw, N.L.; Dudley, J.G.; Saab, V.A.; Kinney, J.W.
Individual grazing systems are often promoted as a panacea for perceived rangeland management problems. However, studies of grazing systems over long periods are limited and those directly comparing more than a few grazing strategies at a time are limited. Seven simulated grazing strategies were a...
Pasture 2 x-f;; Pasture 1 Pasture 2 Pasture 1 ant1 so forth and so forth and so forth h~, tllc pasture being grazed was stocked at this -+e, but the nature of the rotation caused each -lTtnre LO have a grazing equivalent of 25.6 A.U.'s elr :car... operating expenses and net returns f year. Variable expenses of a ranch firm di,,,. . cording to number of producing animals, reph I ments and percent calf or lamb crop. Therein- expenses such as hauling, marketing, taxes, breeclir: 1 shearing...
Huss, Donald L.; Allen, Jerry V.
Practices for endo and ectoparasite control in beef cattle were evaluated in two independent experiments. First, the effects of rotenone on Rhipicephalus (Boophilus) microplus ticks were evaluated in vitro and in experimentally infected calves. In the second trial, the effects of grazing systems associated with endo and ectoparasite treatments on parasite burden and weight gain of naturally parasited animals were evaluated. Rotenone showed acaricide action on larvae and engorged ticks during in vitro tests and on larvae in experimentally infected calves. Three treatments with endectocide decreased (P < .05) the number of EPG and ticks and increased (P < .05) the weight gain in the dry season. Animals treated with only one application of levamisole showed EPG intermediate and different (P < .05) from the groups treated with endectocide (lower) and control (higher) in the dry season, but the weight gain obtained with this treatment did not differ from the control group. During the raining season the animals treated with fipronil were significantly less parasited by horn fly, tick and larvae of Dermatobia hominis and the group treated with rotenone were significantly less parasited by horn fly in relation to control. Animals under rotational grazing showed significantly higher EPG than those under continuous grazing. Three treatments with endectocide in the dry season plus three acaricide treatments with fipronil in the raining season reduced EPG, tick, and screw worm larva counts, and provided a significant increase (23 kg) of live weight gain in relation to untreated animals. PMID:20040207
Catto, João B; Bianchin, Ivo; Santurio, Jânio M; Feijó, Gelson L D; Kichel, Armindo N; Silva, José M da
The objective of this work was to study the effect of dairy system, herd within dairy system, and characteristics of individual cows (parity, days in milk, and daily milk yield) on the volatile organic compound profile of model cheeses produced under controlled conditions from the milk of individual cows of the Brown Swiss breed. One hundred fifty model cheeses were selected from 1,272 produced for a wider study of the phenotypic and genetic variability of Brown Swiss cows. In our study, we selected 30 herds representing 5 different dairy systems. The cows sampled presented different milk yields (12.3-43.2kg/d), stages of lactation (10-412 d in milk), and parity (1-7). In total, 55 volatile compounds were detected by solid-phase microextraction and gas chromatography-mass spectrometry, including 14 alcohols, 13 esters, 11 free fatty acids, 8 ketones, 4 aldehydes, 3 lactones, 1 terpene, and 1 pyrazine. The most important sources of variation in the volatile organic profiles of model cheeses were dairy system (18 compounds) and days in milk (10 compounds), followed by parity (3 compounds) and milk yield (5 compounds). The model cheeses produced from the milk of tied cows reared on traditional farms had lower quantities of 3-methyl-butan-1-ol, 6-pentyloxan-2-one, 2-phenylethanol, and dihydrofuran-2(3H)-one compared with those reared in freestalls on modern farms. Of these, milk from farms using total mixed rations had higher contents of alcohols (hexan-1-ol, octan-1-ol) and esters (ethyl butanoate, ethyl pentanoate, ethyl hexanoate, and ethyl octanoate) and lower contents of acetic acid compared with those using separate feeds. Moreover, dairy systems that added silage to the total mixed ration produced cheeses with lower levels of volatile organic compounds, in particular alcohols (butan-1-ol, pentan-1-ol, heptan-1-ol), compared with those that did not. The amounts of butan-2-ol, butanoic acid, ethyl-2-methylpropanoate, ethyl-3-methylbutanoate, and 6-propyloxan-2-one increased linearly during lactation, whereas octan-1-ol, 3-methyl-3-buten-1-ol, 2-butoxyethanol, 6-pentyloxan-2-one, and 2,6-dimethylpyrazine showed a more complex pattern during lactation. The effect of the number of lactations (parity) was significant for octan-1-ol, butanoic acid, and heptanoic acid. Finally, concentrations of octan-1-ol, 2-phenylethanol, pentanoic acid, and heptanoic acid increased with increasing daily milk yield, whereas dihydrofuran-2(3H)-one decreased. In conclusion, the volatile organic compound profile of model cheeses from the milk of individual cows was affected by dairy farming system and stage of lactation and, to lesser extent, by parity and daily milk yield. PMID:25682146
Bergamaschi, M; Aprea, E; Betta, E; Biasioli, F; Cipolat-Gotet, C; Cecchinato, A; Bittante, G; Gasperi, F
Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop...
Winter grazing cattle followed by cotton (Gossypium hirsutum L.) offers profits for producers, but could result in soil water depletion and soil compaction. We conducted a 3-yr field study on a Dothan loamy sand (fine-loamy, kaolinitic, thermic Plinthic Kandiudults) to develop a conservation tillage...
Data regarding grazing utilization in the western United States are typically compiled within administrative boundaries(e.g. allotment,pasture). For large areas, an assumption of uniform distribution is seldom valid. Previous studies show that vegetation type, degree of slope, an...
The effects of deferred rotation, time control (Savory Grazing Method), season-long, and livestock exclusion on streambank stability and trout habitat condition in a southwestern Montana riparian zone has been monitored since 1986. Although livestock exclusion appeared to improve channel conditions in 1986, there was no significant difference among any of the treatments thereafter. The decline in trout habitat condition appeared
CLAYTON B. MARLOW; KATHRIN OLSON-RUTZ; JENNIFER ATCHLEY
This project compared forage chicory with brown mid-rib sorghum x sudangrass (BMR) to determine if anti-parasitic effects of chicory could be demonstrated. We evaluated changes in fecal egg counts in two groups of lambs before and after grazing these forages for periods of two to three weeks. Body...
The use of contracts in livestock production has been widespread since at least the 1950s. Under grazing contracts, cattle owners usually place stocker cattle on pasture, owned or leased by a caretaker (e.g. farmer or landowner). These contacts provide farmers an increase in revenue by utilizing win...
Literature with data from dairy cows on pasture was reviewed to evaluate the effects of supplementation on intake, milk production and composition, and ruminal and postruminal digestion. Low dry matter intake (DMI) of pasture has been identified as a major factor limiting milk production by high producing dairy cows. Pasture DMI in grazing cows is a function of grazing time,
F. Bargo; L. D. Muller; E. S. Kolver; J. E. Delahoy
The purpose of this study was to evaluate the anticipated environmental benefits from integrating a dairy farm and a greenhouse; the integration is based on anaerobic digestion of manures to produce biogas energy, biogenic CO2, and digested slurry. A full Life Cycle Assessment (LCA) has been conducted on six modeled cases applicable in British Columbia, to evaluate non-renewable energy consumption, climate change, acidification, eutrophication, respiratory effects and human toxicity. Compared to conventional practice, an integrated system has the potential to nearly halve eutrophication and respiratory effects caused by inorganic emissions and to reduce non-renewable energy consumption, climate change, and acidification by 65-90%, while respiratory effects caused by organic emissions become negative as co-products substitute for other materials. Co-digestion of other livestock manures, greenhouse plant waste, or food and food processing waste with dairy manure can further improve the performance of the integrated system. PMID:24138886
Zhang, Siduo; Bi, Xiaotao Tony; Clift, Roland
Because the reproductive performance of lactating dairy cows influences the profitability of dairy operations, predicting the future reproductive and economic performance of dairy herds through decision support systems would be valuable to dairy producers and consultants. In this study, we present a highly adaptable tool created based on a mathematical model combining Markov chain simulation with partial budgeting to obtain the net present value (NPV; $/cow per year) of different reproductive management programs. The growing complexity of reproductive programs used by dairy farms demands that new decision support systems precisely reflect the events that occur on the farm. Therefore, the model requires productive, reproductive, and economic input data used for simulation of farm conditions to account for all factors related to reproductive management that increase costs and generate revenue. The economic performance of 3 different reproductive programs can be simultaneously compared with the current model. A program utilizing 100% visual estrous detection (ED) for artificial insemination (AI) is used as a baseline for comparison with 2 other programs that may include 100% timed AI (TAI) as well as any combination of TAI and ED. A case study is presented in which the model was used to compare 3 different reproductive management strategies (100% ED baseline compared with two 100% TAI options) using data from a commercial farm in Wisconsin. Sensitivity analysis was then used to assess the effect of varying specific reproductive parameters on the NPV. Under the simulated conditions of the case study, the model indicated that the two 100% TAI programs were superior to the 100% ED program and, of the 100% TAI programs, the one with the higher conception rate (CR) for resynchronized AI services was economically superior despite having higher costs and a longer interbreeding interval. A 4% increase in CR for resynchronized AI was sufficient for the inferior 100% TAI to outperform the superior program. Adding ED to the 100% TAI programs was only beneficial for the program with the lower CR. The improvement in service rate required for the 100% ED program to have the same NPV as the superior 100% TAI program was 12%. The decision support system developed in this study is a valuable tool that may be used to assist dairy producers and industry consultants in selecting the best farm-specific reproductive management strategy. PMID:22118110
Giordano, J O; Fricke, P M; Wiltbank, M C; Cabrera, V E
Performance of a laboratory-scale two-phase anaerobic digestion system treating dairy wastewater was investigated using the pre-determined operating criteria for the anaerobic acidification reactor. The results, obtained from a 9month operation, showed that overall, 90% COD and 95% BOD removal efficiencies at an organic loading rate (OLR) of 5kg COD\\/m3d and a hydraulic retention time (HRT) of 2days were achieved. The
Regula et al. (2004) studied the effect of confinement on dairy cows kept in three intensive husbandry systems: tie stalls with regular exercise during summer but not during winter; tie stalls with regular exercise year-round; and loose-housing with regular outdoor access. The study showed that loose-housing and regular exercise throughout the year had a positive effect on lameness, teat injuries,
This project compared lambs grazing forage chicory (Cichorium intybus L.) with lambs grazing brown mid-rib forage sorghum (Sorghum bicolor (L.) Moench.) x sudangrass (Sorghum sudanense Piper) hybrid (BMR) to determine if anti-parasitic effects of chicory could be demonstrated. Lambs grazed these fo...
your dairy goatyour dairy goatyour dairy goatyour dairy goatyour dairy goat The Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy GoatThe Modern Dairy Goat The modern dairy goat-quality feed, and should be milked properly. With the exception of bucks during breeding season, goats do
New Hampshire, University of
Concern about world population increase, food security, and the environmental burdens of food production have made food-waste reduction a social and environmental priority. In this context, the quantification of dairy product waste is especially difficult due to the varied means of disposal, by solid and liquid waste streams, and due to inclusion as an ingredient in many processed foods. In this study, food intake data from the Australian National Nutrition Survey (>13,000 participants; >4,500 food items) were disaggregated into basic foods and total national dairy product intake was expressed in whole-milk equivalents. This result was compared with total domestic milk supply, indicating a level of waste of 29% for dairy products in the Australian food system. With national food-waste reduction targets becoming increasingly common, reliable estimates of food waste at the national scale are important for goal setting, baseline reporting, and performance monitoring. For this purpose, the systems approach to assessing food waste demonstrated in this project is deemed to have advantages over other common methods of food-waste assessment, such as bin audits, waste diaries, and surveys. PMID:25064645
Ridoutt, B G; Baird, D L; Bastiaans, K; Darnell, R; Hendrie, G A; Riley, M; Sanguansri, P; Syrette, J; Noakes, M; Keating, B A
The present study describes the implementation of a food safety system in a dairy processing plant located in the State of São Paulo, Brazil, and the challenges found during the process. In addition, microbiological indicators have been used to assess system's implementation performance. The steps involved in the implementation of a food safety system included a diagnosis of the prerequisites, implementation of the good manufacturing practices (GMPs), sanitation standard operating procedures (SSOPs), training of the food handlers, and hazard analysis and critical control point (HACCP). In the initial diagnosis, conformity with 70.7% (n=106) of the items analyzed was observed. A total of 12 critical control points (CCPs) were identified: (1) reception of the raw milk, (2) storage of the raw milk, (3 and 4) reception of the ingredients and packaging, (5) milk pasteurization, (6 and 7) fermentation and cooling, (8) addition of ingredients, (9) filling, (10) storage of the finished product, (11) dispatching of the product, and (12) sanitization of the equipment. After implementation of the food safety system, a significant reduction in the yeast and mold count was observed (p<0.05). The main difficulties encountered for the implementation of food safety system were related to the implementation of actions established in the flow chart and to the need for constant training/adherence of the workers to the system. Despite this, the implementation of the food safety system was shown to be challenging, but feasible to be reached by small-scale food industries. PMID:23153286
Cusato, Sueli; Gameiro, Augusto H; Corassin, Carlos H; Sant'ana, Anderson S; Cruz, Adriano G; Faria, José de Assis F; de Oliveira, Carlos Augusto F
Kamdhenu Dairy was one of the biggest dairy unions in India that came into being in 1969. Kamdhenu dairy, with an annual sales turnover of Rs.5250 million, was procuring its milk from the regular suppliers residing in the villages using its own procurement network. The same network was being used to market other dairy products and essential items like fodder
Debasis Pradhan; Shabad Kalra; Sangeeta Srinivas
Evaluation of lifetime productivity is sensible to target interventions for improving productivity of smallholder dairy systems in the highlands of East Africa, because cows are normally not disposed of based on productive reasons. Feeding strategies and involuntary culling may have long-term effects on productive (and therefore economic) performance of dairy systems. Because of the temporal scale needed to evaluate lifetime productivity, experimentation with feedstuffs in single lactations is not enough to assess improvements in productivity. A dynamic modelling approach was used to explore the effect of feeding strategies on the lifetime productivity of dairy cattle. We used LIVSIM (LIVestock SIMulator), an individual-based, dynamic model in which performance depends on genetic potential of the breed and feeding. We tested the model for the highlands of Central Kenya, and simulated individual animals throughout their lifetime using scenarios with different diets based on common feedstuffs used in these systems (Napier grass, maize stover and dairy concentrates), with and without imposing random mortality on different age classes. The simulations showed that it is possible to maximise lifetime productivity by supplementing concentrates to meet the nutrient requirements of cattle during lactation, and during early development to reduce age at first calving and extend productive life. Avoiding undernutrition during the dry period by supplementing the diet with 0.5 kg of concentrates per day helped to increase productivity and productive life, but in practice farmers may not perceive the immediate economic benefits because the results of this practice are manifested through a cumulative, long-term effect. Survival analyses indicated that unsupplemented diets prolong calving intervals and therefore, reduce lifetime productivity. The simulations with imposed random mortality showed a reduction of 43% to 65% in all productivity indicators. Milk production may be increased on average by 1400 kg per lactation by supplementing the diet with 5 kg of concentrates during early lactation and 1 kg during late lactation, although the optimal supplementation may change according to milk and concentrate prices. Reducing involuntary culling must be included as a key goal when designing interventions to improve productivity and sustainability of smallholder dairy systems, because increasing lifetime productivity may have a larger impact on smallholders' income than interventions targeted to only improving daily milk yields through feeding strategies. PMID:22444823
Rufino, M C; Herrero, M; Van Wijk, M T; Hemerik, L; De Ridder, N; Giller, K E
Sweden has a national disease-recording system based on veterinary reporting. From this system, all cattle-disease records are transferred to the dairy industry cattle database (DDD) where they are used for several purposes including research and dairy-health statistics. Our objective was to evaluate the completeness of this data source by comparing it with disease data registered by dairy farmers. The proportion
M. Mörk; A. Lindberg; S. Alenius; I. Vågsholm; A. Egenvall
This research assesses the potential for co-treatment of a dairy wastewater with a domestic wastewater in a lab-scale, continuous-flow, activated sludge system. To evaluate the influence of the dairy waste contribution, seven runs were conducted with each run being a mixture of dairy wastewater (either cheese or milk) in different ratios ranging from 1:0.01 to 1:0.30 by volume. More than 87% of the carbon was removed for both waste additions; however, while 95% ammonia-nitrogen removal was recorded for the cheese waste, only 75% removal was obtained for the milk. Kinetic studies for carbon consumption revealed a first-order model with lower kinetic constants as the cheese waste proportion increased. Specific carbon consumption rates indicated that the biomass had not reached its maximum potential to degrade carbon. The ability of the biomass to settle was hindered when the Gram negative to Gram positive filamentous bacteria ratio increased to approximately 1.5. PMID:25204524
Sparchez, E; Elefsiniotis, P; Wareham, D G; Fongsatitkul, P
The effects on dairy cow health and performance of applying very high rates of inorganic fertilizer nitrogen to grassland have been studied. Two comparable areas of grassland provided the grazing and silage requirements for two separate herds of Friesian dairy cows. These two areas received 250 and 750kg fertilizer nitrogen ha-1 yr-1. The higher rate was chosen to represent a
N. B. Coombe; A. E. M. Hood
Group housing of preweaned dairy calves is a growing practice in the United States. The objective of this practice is to increase the average daily gain of calves in a healthy and humane environment while reducing labor requirements. However, feeding protocols, commingling of calves, and occurrence of disease in different calf-housing systems may affect the prevalence of antimicrobial drug-resistant bacteria. This study evaluated the effect of a group pen-housing system and individual pen-housing system on antimicrobial resistance trends in fecal Escherichia coli of preweaned dairy calves and on the prevalence of environmental Salmonella. Twelve farms from central New York participated in the study: 6 farms using an individual pen-housing system (IP), and 6 farms using a group pen-housing system (GP). A maximum of 3 fecal E. coli isolates per calf was tested for susceptibility to 12 antimicrobial drugs using a Kirby-Bauer disk diffusion assay. Calves in GP had a significantly higher proportion of E. coli resistant to ciprofloxacin and nalidixic acid, whereas calves in IP had a significantly higher proportion of E. coli resistant to ampicillin, ceftiofur, gentamycin, streptomycin, and tetracycline. Calf-housing system had an effect on resistance to individual antimicrobial drugs in E. coli, but no clear-cut advantage to either system was noted with regard to overall resistance frequency. No outstanding difference in the richness and diversity of resistant phenotypes was observed between the 2 calf-housing systems. PMID:25306277
Pereira, R V; Siler, J D; Ng, J C; Davis, M A; Warnick, L D
Although sheep milk production is a significant sector for the European Mediterranean countries, it shows serious competitiveness gaps. Minimizing the ecological impacts of dairy sheep farming systems could represent a key factor for farmers to bridging the gaps in competitiveness of such systems and also obtaining public incentives. However, scarce is the knowledge about the environmental performance of Mediterranean dairy sheep farms. The main objectives of this paper were (i) to compare the environmental impacts of sheep milk production from three dairy farms in Sardinia (Italy), characterized by different input levels, and (ii) to identify the hotspots for improving the environmental performances of each farm, by using a Life Cycle Assessment (LCA) approach. The LCA was conducted using two different assessment methods: Carbon Footprint-IPCC and ReCiPe end-point. The analysis, conducted "from cradle to gate", was based on the functional unit 1 kg of Fat and Protein Corrected Milk (FPCM). The observed trends of the environmental performances of the studied farming systems were similar for both evaluation methods. The GHG emissions revealed a little range of variation (from 2.0 to 2.3 kg CO2-eq per kg of FPCM) with differences between farming systems being not significant. The ReCiPe end-point analysis showed a larger range of values and environmental performances of the low-input farm were significantly different compared to the medium- and high-input farms. In general, enteric methane emissions, field operations, electricity and production of agricultural machineries were the most relevant processes in determining the overall environmental performances of farms. Future research will be dedicated to (i) explore and better define the environmental implications of the land use impact category in the Mediterranean sheep farming systems, and (ii) contribute to revising and improving the existing LCA dataset for Mediterranean farming systems. PMID:25265396
Vagnoni, E; Franca, A; Breedveld, L; Porqueddu, C; Ferrara, R; Duce, P
Grazing lawns are a distinct grassland community type, characterised by short-stature and with their persistence and spread promoted by grazing. In Africa, they reveal a long co-evolutionary history of grasses and large mammal grazers. The attractiveness to grazers of a low-biomass sward lies in the relatively high quality of forage, largely due to the low proportion of stem material in the sward; this encourages repeat grazing that concomitantly suppresses tall-grass growth forms that would otherwise outcompete lawn species for light. Regular grazing that prevents shading and maintains sward quality is thus the cornerstone of grazing lawn dynamics. The strong interplay between abiotic conditions and disturbance factors, which are central to grazing lawn existence, can also cause these systems to be highly dynamic. Here we identify differences in growth form among grazing lawn grass species, and assess how compositional differences among lawn types, as well as environmental variables, influence their maintenance requirements (i.e. grazing frequency) and vulnerability to degradation. We also make a clear distinction between the processes of lawn establishment and lawn maintenance. Rainfall, soil nutrient status, grazer community composition and fire regime have strong and interactive influences on both processes. However, factors that concentrate grazing pressure (e.g. nutrient hotspots and sodic sites) have more bearing on where lawns establish. Similarly, we discuss the relevance of enhanced rates of nitrogen cycling and of sodium levels to lawn maintenance. Grazer community composition and density has considerable significance to grazing lawn dynamics; not all grazers are adapted to foraging on short-grass swards, and differences in body size and relative mouth dimensions determine which species are able to convert tall-grass swards into grazing lawns under different conditions. Hence, we evaluate the roles of different grazers in lawn dynamics, as well as the benefits that grazer populations derive from having access to grazing lawns. The effects of grazing lawns can extend well beyond their borders, due to their influence on grazer densities, behaviour and movements as well as fire spread, intensity and frequency. Variation in the area and proportion of a landscape that is grazing lawn can thus have a profound impact on system dynamics. We provide a conceptual model that summarises grazing lawn dynamics, and identify a rainfall range where we predict grazing lawns to be most prevalent. We also examine the biodiversity associated with grazing lawn systems, and consider their functional contribution to the conservation of this biodiversity. Finally, we assess the utility of grazing lawns as a resource in a rangeland context. PMID:25231416
Hempson, Gareth P; Archibald, Sally; Bond, William J; Ellis, Roger P; Grant, Cornelia C; Kruger, Fred J; Kruger, Laurence M; Moxley, Courtney; Owen-Smith, Norman; Peel, Mike J S; Smit, Izak P J; Vickers, Karen J
A microcomputer-based herd management information system was implemented as part of the herd health program provided to 13 dairy clients by the Ontario Veterinary College, University of Guelph. The study was conducted over a two year period. Data were collected from on-farm event diaries, veterinary visit reports, and production testing information. Selected indices of reproduction, udder health, production, and heifer performance were reported. It was concluded that the implementation of a microcomputer-based information management system, operated as a bureau service, was feasible. However, limitations to the implementation in veterinary practice were identified. PMID:17423945
Lissemore, Kerry D.; Leslie, Ken E.; Menzies, Paula I.; Martin, S. Wayne; Meek, Alan H.; Etherington, Wayne G.
Methane emission was measured from 10 dairy cows and 12 wether sheep grazing kikuyu grass? (Pennisetum clandestinum) dominant pastures at Waimate North, Northland, in February 1997 and March 1999, and from 10 dairy cows grazing summer grass? (Digitaria sanguinalis) dominant pasture at Edgecumbe, Bay of Plenty, in March 2000. Methane emission was measured from each animal for 5 consecutive days
M. J. Ulyatt; K. R. Lassey; I. D. Shelton; C. F. Walker
49 Ceti is a young star that hosts a debris disk with an unusually large amount of carbon monoxide gas. This excess gas has been attributed to frequent collisions of comets within the disk. (Zuckerman & Song, 2012). Since 49 Ceti disk is nearly edge-on to our line of sight, it is a prime target to observe disk gas and evaporated material from star-grazing comets using absorption spectroscopy, as shown by detection of time-variable circumstellar absorption in optical spectra of the star (Montgomery & Welsh 2012). Here we discuss ultraviolet spectra of 49 Ceti taken using the Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) during two separate visits six days apart. The spectra show time-variable and highly Doppler shifted absorption features from ionized gaseous species. The maximum velocity of the time-variable gas corresponds to a minimum distance from the star of 0.06 AU. These features very likely come from star-grazing comets. Lower limits on element abundances in the gas were found using the apparent optical depth method. The variable comet gas appears carbon rich, despite the disk gas as a whole showing strong absorption features from both carbon and oxygen (Roberge et al., 2014, in press).
Miles, Brittany E.; Roberge, Aki; Welsh, Barry
The experimental evaluation of grazing systems represents a highly visible and lengthy chapter in the history of the rangeland profession. Although experimentation has largely concluded, contrasting interpretations still remain regarding the potential benefits of rotational grazing systems on rangel...
Dairy waste was found to have a natural population of microorganisms capable of seeding an MFC. Dairy wastewater also proved to be a very effective substrate. Different graphite electrode materials provided varying levels of electrical energy generation, demonstrating with gr...
Yearly production and reproduction data on dairy farms in The Netherlands were obtained to determine whether management information systems significantly improved herd performance variables (management information systems (MIS) effects). The analysis included 357 adopters of a management information system and 357 herds were used as controls. The data comprised years 1987 through 1996, and included for the adopters both the
M. A. Tomaszewski; A. A. Dijkhuizen; R. B. M. Huirne
fistula, first used by Torell (1954), for nutrition studies, permits accurate sampling of forage consumed by grazing animals. Cook et al. , (1958), adapted the esophageal cannual method for diet determination under natural grazing conditions. Other... workers (Edlefsen et al. , 1960; Arnold et al. , 1964; Kothman, 1968; Malechek, 1970; and Weir and Torell, 1959) have successfully used the esophageal fistula as a means of studying the diets of grazing animals. Drawe and Box (1968), determined...
Taylor, Charles Andrew
Calving body condition score (BCS) is an important determinant of early-lactation dry matter intake, milk yield, and disease incidence. The current study investigated the metabolic and molecular changes induced by the change in BCS. A group of cows of mixed age and breed were managed from the second half of the previous lactation to achieve mean group BCS (10-point scale) that were high (HBCS, 5.5; n=20), medium (MBCS, 4.5; n=18), or low (LBCS, 3.5; n=19). Blood was sampled at wk -4, -3, -2, 1, 3, 5, and 6 relative to parturition to measure biomarkers of energy balance, inflammation, and liver function. Liver was biopsied on wk 1, 3, and 5 relative to parturition, and 10 cows per BCS group were used for transcript profiling via quantitative PCR. Cows in HBCS and MBCS produced more milk and had greater concentrations of nonesterified fatty acids and ?-hydroxybutyrate postpartum than LBCS. Peak concentrations of nonesterified fatty acids and ?-hydroxybutyrate and greater hepatic triacylglycerol concentrations were recorded in HBCS at wk 3. Consistent with blood biomarkers, HBCS and MBCS had greater expression of genes associated with fatty acid oxidation (CPT1A, ACOX1), ketogenesis (HMGCS2), and hepatokines (FGF21, ANGPTL4), whereas HBCS had the lowest expression of APOB (lipoprotein transport). Greater expression during early lactation of BBOX1 in MBCS and LBCS suggested greater de novo carnitine synthesis. The greater BCS was associated with lower expression of growth hormone/insulin-like growth factor-1 signaling axis genes (GHR1A, IGF1, and IGFALS) and greater expression of gluconeogenic genes. These likely contributed to the higher milk production and greater gluconeogenesis. Despite greater serum haptoglobin around calving, cows in HBCS and MBCS had greater blood albumin. Cows in MBCS, however, had a higher albumin:globulin ratio, probably indicating a less pronounced inflammatory status and better liver function. The marked decrease in expression of NFKB1, STAT3, HP, and SAA3 coupled with the increase in ALB on wk 3 in MBCS cows were consistent with blood measures. Overall, results suggest that the greater milk production of cows with higher calving BCS is associated with a proinflammatory response without negatively affecting expression of genes related to metabolism and the growth hormone/insulin-like growth factor-1 axis. Results highlight the sensitivity of indicators of metabolic health and inflammatory state to subtle changes in calving BCS and, collectively, indicate a suboptimal health status in cows calving at either BCS 3.5 or 5.5 relative to BCS 4.5. PMID:25497809
Akbar, H; Grala, T M; Vailati Riboni, M; Cardoso, F C; Verkerk, G; McGowan, J; Macdonald, K; Webster, J; Schutz, K; Meier, S; Matthews, L; Roche, J R; Loor, J J
Abstract Livestock grazing has been considered detrimental to wildlife habitat. Managed gazing programs, however, have the potential to maintain habitat diversity and quality. In cases in which single-species management,predominates (sage-grouse [Centrocercus urophasianus] or elk [Cervus elaphus nelsoni] winter range), grazing systems specific to species' needs can be jmplemented. Managed livestock grazing can have 4 general impacts on vegetation: 1) alter
United States organic dairy production has increased to meet the growing demand for organic milk. Despite higher prices received for milk, organic dairy farmers have come under increasing financial stress due to increases in concentrated feed prices over the past few years, which can make up one-third of variable costs. Market demand for milk has also leveled in the last year, resulting in some downward pressure on prices paid to dairy farmers. Organic dairy farmers in the Northeast United States have experimented with growing different forage and grain crops to maximize on-farm production of protein and energy to improve profitability. Three representative organic feed systems were simulated using the integrated farm system model for farms with 30, 120, and 220 milk cows. Increasing intensity of equipment use was represented by organic dairy farms growing only perennial sod (low) to those with corn-based forage systems, which purchase supplemental grain (medium) or which produce and feed soybeans (high). The relative profitability of these 3 organic feed systems was strongly dependent on dairy farm size. From results, we suggest smaller organic dairy farms can be more profitable with perennial sod-based rather than corn-based forage systems due to lower fixed costs from using only equipment associated with perennial forage harvest and storage. The largest farm size was more profitable using a corn-based system due to greater economies of scale for growing soybeans, corn grain, winter cereals, and corn silages. At an intermediate farm size of 120 cows, corn-based forage systems were more profitable if perennial sod was not harvested at optimum quality, corn was grown on better soils, or if milk yield was 10% higher. Delayed harvest decreased the protein and energy content of perennial sod crops, requiring more purchased grain to balance the ration and resulting in lower profits. Corn-based systems were less affected by lower perennial forage quality, as corn silage is part of the forage base. Growing on better soils increased corn yields more than perennial forage yields. Large corn-based organic dairy farms that produced and fed soybeans minimized off-farm grain purchases and were the most profitable among large farms. Although perennial sod-based systems purchased more grain, these organic systems were more profitable under timely forage harvest, decreased soil quality, and relatively lower purchased energy prices and higher protein supplement prices. PMID:22032396
Hoshide, A K; Halloran, J M; Kersbergen, R J; Griffin, T S; DeFauw, S L; LaGasse, B J; Jain, S
Methane (CH4) from ruminants contributes one third to global agricultural greenhouse gas emissions. Eddy covariance (EC) technique has been extensively used at various flux sites to investigate carbon dioxide exchange of ecosystems. Since the development of fast CH4 analysers the instrumentation at many flux sites have been amended for these gases. However the application of EC over pastures is challenging due to the spatial and temporal uneven distribution of CH4 point sources induced by the grazing animals. We applied EC measurements during one grazing season over a pasture with 20 dairy cows (mean milk yield: 22.7 kg d-1) managed in a rotational grazing system. Individual cow positions were recorded by GPS trackers to attribute fluxes to animal emissions using a footprint model. Methane fluxes with cows in the footprint were up to two orders of magnitude higher than ecosystem fluxes without cows. Mean cow emissions of 423 ± 24 g CH4 head-1 d-1 (best guess of this study) correspond well to animal respiration chamber measurements reported in the literature. However a systematic effect of the distance between source and EC tower on cow emissions was found which is attributed to the analytical footprint model used. We show that the EC method allows to determine CH4 emissions of grazing cows if the data evaluation is adjusted for this purpose and if some cow distribution information is available.
Felber, R.; Münger, A.; Neftel, A.; Ammann, C.
This paper specifies the pasture growth module of a model for simulating grazing systems for ruminants and the soil moisture budget that drives pasture growth. Both modules operate at a daily time step. The pasture growth module is quite general in structure but recognises four functional groups of pasture plants: annual and perennial species are distinguished, as are grasses and
A. D. Moore; J. R. Donnelly; M. Freer
System With and Without a Settling Basin: 300 Cow Dairy. 67 3. 2 Initial Investment in a Dairy Waste Management System With and Without a Settling Basin: 720 Cow Dairy. 67 3. 3 Estimated Dairy Waste Disposal Costs With and Without a Settling Basin...: 300 Cow Dairy. . . . . . 71 3. 4 Estimated Dairy Waste Disposal Costs With and Without a Settling Basin: 720 Cow Dairy. . . . . . . 71 3. 5 Implications of Water Use and Drylot Size on Initial Investment: 300 Cow Dairy. . . . . . . . . . . 78 3. 6...
Schmucker, John Francis
Two enhanced biological phosphorus removal (EBPR) sequencing batch reactors (SBR1, SBR2) treating liquid dairy manure were operated with the same hydraulic retention time (HRT) and solids retention time (SRT), but with different aeration cycles. During eight months of operation, both SBRs achieved good removal of total phosphorus (P) (TP; 56.8 and 73.5% for SBR1 and SBR2 respectively) and of orthophosphate (OP; 76.2 vs. 82.7%, P < 0.05). Growth dynamics of presumptive phosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) were examined by quantitative polymerase chain reaction (qPCR). SBR1 was enriched with a greater abundance of PAOs while SBR2 was characterized by a greater abundance of GAOs. These results demonstrate the capability of EBPR of dairy manure and challenge conventional wisdom, since greater abundance of PAOs in EBPR system was not associated with improved OP removal and greater abundance of GAOs did not indicate deterioration of the EBPR system. PMID:25112034
Liu, Ze-Hua; Pruden, Amy; Ogejo, Jactone Arogo; Knowlton, Katharine F
Health and production management strategies influence environmental impacts of dairies. The objective of this paper was to measure risk factors on health and production parameters on six organic and conventional bovine, caprine, and ovine dairy herds in southeastern Brazil over six consecutive years (2006-2011). The organic operations had lower milk production per animal (P???0.05), lower calf mortality (P???0.05), less incidence of mastitis (P???0.05), fewer rates of spontaneous abortions (P???0.05), and reduced ectoparasite loads (P???0.05) compared to conventional herds and flocks. Organic herds, however, had greater prevalence of internal parasitism (P???0.05) than conventional herds. In all management systems, calves, kids, and lambs had greater oocyte counts than adults. However, calves in the organic group showed lower prevalence of coccidiosis. In addition, animals in the organic system exhibited lower parasitic resistance to anthelmintics. Herd genetic potential, nutritive value of forage, feed intake, and pasture parasite loads, however, may have influenced productive and health parameters. Thus, although conventional herds showed greater milk production and less disease prevalence, future research might quantify the potential implications of these unreported factors. PMID:25015183
Silva, Jenevaldo B; Fagundes, Gisele M; Soares, João P G; Fonseca, Adivaldo H; Muir, James P
We used two years of eddy covariance (EC) measurements collected over an intensively grazed dairy pasture to better understand the key drivers of changes in soil organic carbon stocks. Analysing grazing systems with EC measurements poses significant challenges as the respiration from grazing animals can result in large short-term CO2 fluxes. As paddocks are grazed only periodically, EC observations derive from a mosaic of paddocks with very different exchange rates. This violates the assumptions implicit in the use of EC methodology. To test whether these challenges could be overcome, and to develop a tool for wider scenario testing, we compared EC measurements with simulation runs with the detailed ecosystem model CenW 4.1. Simulations were run separately for 26 paddocks around the EC tower and coupled to a footprint analysis to estimate net fluxes at the EC tower. Overall, we obtained good agreement between modelled and measured fluxes, especially for the comparison of evapotranspiration rates, with model efficiency of 0.96 for weekly averaged values of the validation data. For net ecosystem productivity (NEP) comparisons, observations were omitted when cattle grazed the paddocks immediately around the tower. With those points omitted, model efficiencies for weekly averaged values of the validation data were 0.78, 0.67 and 0.54 for daytime, night-time and 24-hour NEP, respectively. While not included for model parameterisation, simulated gross primary production also agreed closely with values inferred from eddy covariance measurements (model efficiency of 0.84 for weekly averages). The study confirmed that CenW simulations could adequately model carbon and water exchange in grazed pastures. It highlighted the critical role of animal respiration for net CO2 fluxes, and showed that EC studies of grazed pastures need to consider the best approach of accounting for this important flux to avoid unbalanced accounting. PMID:25634732
Kirschbaum, Miko U F; Rutledge, Susanna; Kuijper, Isoude A; Mudge, Paul L; Puche, Nicolas; Wall, Aaron M; Roach, Chris G; Schipper, Louis A; Campbell, David I
In the humid tropics, small ruminant farmers have to deal with gastrointestinal parasitic nematodes (GIN), among which anthelmintic resistant (AR) populations are rapidly spreading. Although targeted selective treatments (TSTs) are being increasingly used in breeding stock, suppressive drenchings remain the rule in younger animals, for safety and ease of implementation. Until now, the weaned animals are grazed on dedicated plots, making the selection and spread of AR parasites inevitable. Given that GINs disseminate through pastures, we compared the usual grazing system (control) to a "leader-follower" grazing system (LF) for managing the entire GIN population at the farm scale. There were no significant differences between treatments for the dam reproductive parameters and level of GIN infection nor for the pre-weaning death rate of the kids. The 70-day weight of the litter was significantly lower for LF than for control goats (9.71 vs. 11.64 kg, P?0.05). Although they were more infested with GIN (1860 vs. 966 epg, P?0.05), the LF weaned animals grew faster (53.4 vs. 40.8 g day(-1), P?0.05) and their death rate was lower (4.0 vs. 7.7 %, P?0.05). The overall animal output was estimated to 1010 [911; 1086] vs. 966 [885; 1046]?kg LW ha(-1) year(-1), for LF and control grazing systems, respectively. Additionally, the LF grazing system would make the stocking rate easier to manage. Therefore, it is to be recommended as a complement of TSTs in sustainable small ruminant farming. PMID:25681011
Mahieu, Maurice; Gauthier, Valérie; Arquet, Rémy; Calif, Brigitte; Archimède, Harry; Mandonnet, Nathalie
Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003 Sponsored by University of California Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003 And" Davis, CA 1918 University of California Dairy Goat Day 2003Dairy Goat Day 2003Dairy Goat Day 2003Dairy
Schladow, S. Geoffrey
The chapter describes methods to assess grazing rates, grazer preferences, and grazer impacts, by mobile organisms living in the canopy or in the rhizome layer in any seagrass system. One set of methods quantifies grazing activity in small to medium sized, mobile organisms livin...
Organic farming conserves natural resources, promotes biodiversity, guarantees animal welfare and obtains healthy products from raw materials through natural processes. In order to evaluate possibilities of increasing organic animal production, this study proposes a farm-scale multicriteria method for assessing the conversion of dairy goat systems to the organic model. In addition, a case study in the Northern Sierra of Seville, southern Spain, is analysed. A consensus of expert opinions and a field survey are used to validate a list of potential indicators and issues for assessing the conversion, which consider not only the European Community regulations for organic livestock farming, but also agroecological principles. As a result, the method includes 56 variables integrated in nine indicators: Nutritional management, Sustainable pasture management, Soil fertility and contamination, Weed and pest control, Disease prevention, Breeds and reproduction, Animal welfare, Food safety and Marketing and management. The nine indicators are finally integrated in a global index named OLPI (Organic Livestock Proximity Index). Application of the method to a case study with 24 goat farms reveals an OLPI value of 46.5% for dairy goat farms located in mountain areas of southern Spain. The aspects that differ most from the agroecological model include soil management, animal nutrition and product marketing. Results of the case study indicate that the proposed method is easy to implement and is useful for quantifying the approximation of conventional farms to an organic model. PMID:22436287
Mena, Y; Nahed, J; Ruiz, F A; Sánchez-Muñoz, J B; Ruiz-Rojas, J L; Castel, J M
In a dairy farm system during conversion from conventional to organic farming practice, the effects of different cattle manure treatment methods, fertilisation level and soil compaction were studied over a period of 6 years. Yields, botanical composition, earthworm quantity and soil porosity were monitored. The manure was treated as diluted, aerated and mechanically separated slurry (solid compost on tilled land
5/4/2011 1 Maintaining and Restoring Riparian Areas in Grazed Ecosystems Ken Tate Â UC Davis coastal to Sierra riparian systems Â there is significant effort to restore riparian areas in grazed watersheds I can be good! We can prescribe grazing to support riparian restoration objectives I Promise
Integrating livestock with cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) production systems by grazing winter-annuals can offer additional income for producers provided it does not result in yield-limiting soil compaction. We conducted a 3-year field study on a Dothan loamy sand (fine-loamy, kaolinitic, thermic plinthic kandiudults) in southern Alabama, USA to determine the influence of tillage system prior
Guillermo Siri-Prieto; D. Wayne Reeves; Randy L. Raper
An online engagement exercise documented the views of Canadian and U.S. participants affiliated and unaffiliated with the dairy industry on the issue of pasture access for dairy cows. A total of 414 people participated in 10 independent web forums. Providing access to more natural living conditions, including pasture, was viewed as important for the large majority of participants, including those affiliated with the dairy industry. This finding is at odds with current practice on the majority of farms in North America that provide little or no access to pasture. Participant comments showed that the perceived value of pasture access for dairy cattle went beyond the benefits of eating grass; participants cited as benefits exposure to fresh air, ability to move freely, ability to live in social groups, improved health, and healthier milk products. To accommodate the challenges of allowing pasture access on farms, some participants argued in favor of hybrid systems that provide a mixture of indoor confinement housing and grazing. Understanding the beliefs and concerns of participants affiliated and unaffiliated with the dairy industry allows for the identification of contentious topics as well as areas of agreement; this is important in efforts to better harmonize industry practices with societal expectations. PMID:25261215
Schuppli, C A; von Keyserlingk, M A G; Weary, D M
We assessed resources, challenges and prospects of the dairy industries in four districts of Bangladesh (Mymensingh, Satkhira, Chittagong and Sirajganj) with the participation of 8 to 12 dairy farm families in each district. We used ten participatory rural appraisal (PRA) tools, namely social mapping, semistructured interview, activity profiles, seasonal calendar, pie charts, mobility diagram, matrix ranking, preference ranking and scoring, system analysis diagram and focus group discussion in 57 PRA sessions from September through October 2002. Dairying contributed more to family income (63 to 74%) and utilized a smaller portion of land than did crops. Twenty seven to 49% of cattle feed is rice straw. Only Sirajganj and Chittagong had limited, periodic grazing facilities. Fodder (Napier; Pennisetum purpureum) cultivation was practiced in Sirajganj and Satkhira. Fodder availability increased milk production and decreased disease occurrence. Friesian crossbred cows were ranked best as dairy cattle. The present utilization of veterinary and AI services was ranked highly. Farmers outside the milk union desired milk purchasing centres as the most required service in the future. They identified veterinary and AI services as inadequate and desired significant improvements. The PRA tools effectively identified resources, constraints, opportunities and farmers' perspectives related to the dairy industries in Bangladesh. PMID:18265866
Shamsuddin, M; Alam, M M; Hossein, M S; Goodger, W J; Bari, F Y; Ahmed, T U; Hossain, M M; Khan, A H M S I
Ciliated protists are important predators of bacteria in many aquatic habitats, including sediments. Since, many biochemical\\u000a transformations within the nitrogen cycle are performed by bacteria, ciliates could have an indirect impact on the nitrogen\\u000a cycle through selective grazing on nitrogen-transforming bacteria. As a case study, we examined ciliate grazing on nitrifying\\u000a bacteria of the genera Nitrosomonas and Nitrospira. All experiments
Elke Neubacher; Mario Prast; Ernst-Josef Cleven; Ulrike-Gabriele Berninger
A lagoon-type methane recovery system was designed for the Cal Poly Dairy, which milks 130 cows with a total population of 296 animals. Most of the herd is housed in freestall barns where the manure is deposited on concrete and flushed with fresh or recycled water to an existing lagoon with a volume of 19,300 cubic meters. The design includes a new, primary covered lagoon of 17,000 cubic meters volume. The floating cover will be made of very low density polyethylene (VLDPE), with an area of 4,500 square meters. The predicted output of the lagoon is an average of over 310 cubic meters of biogas per day containing 60 percent methane. The methane production from the covered lagoon is adequate to produce 18 to 24 kW on a continuous basis from the present cow population. In order to account for future herd size increases, a 40 kW engine generator was specified to operate in parallel with the utility system at a varying level of output controlled by the biogas supply. The non-economic benefits of this covered lagoon include the demonstration of its operation to the students and visitors at Cal Poly which in turn will serve the California Dairy Community. Odor control is the most important non-economic benefit. Conversion of volatile solids to biogas and recovery and use of the biogas limits odor to surrounding areas. The economic benefits of the methane recovery system include the approximately 160,000 kWh of electricity produced annually, worth almost $13,000. Financial analyses for the project showed a payback of 13.7 years with a 4% internal rate of return.
Williams, D.W. [ICF, Inc., Universal City, CA (United States); Moser, M. [Resource Conservation Management, Inc., Berkeley, CA (United States); Smith, J. [BioResource and Ag. Engineering Dept., San Luis Obispo, CA (United States)
The necessity to work in the focal plane of the primary mirrors has been one of the factors limiting the utility of grazing incidence telescopes in X-ray astronomy. In connection with the reported investigation, computer ray tracing programs have been used to study the performance of several grazing incidence relay optics (GIRO) systems used together with a large nested solar X-ray telescope. It was found that GIRO magnifiers are useful to map appropriate sized regions of the sun onto available CCD detectors. GIRO collimators can be used together with an X-ray spectrometer to study the X-ray spectrum from very small regions on the sun. Attention is given to the stationary mode, the tracking mode, and the size of GIRO elements. It is found that for a given GIRO size and magnification a use of the diverging system has the advantage of reducing the overall length of the main telescope-GIRO combination. However, the resolution provided by the diverging GIRO may not be as good as that obtained with the corresponding converging GIRO.
Chase, R. C.; Davis, J. M.; Krieger, A. S.; Underwood, J. H.
The purpose of this study was to evaluate the most common simultaneous and individual segment postures in terms of body and finger posture classifications. Observations were made at three dairy farms. One employed a tethering system and the other two used loose-housing systems. The evaluations of the tethering system were performed through six processes that were subdivided into 11 operations, whereas only one process of 'milking' was investigated in loose-housing systems. Generally, farmers who worked in both systems bent and/or twisted their upper-body segments and continuously used a power grasp to wrap an object with all five fingers. Posture analyses of the tethering system revealed that 'moving corn' seemed less stressful, whereas 'cleaning udders,' 'attaching the machine,' 'washing the machine,' and 'sweeping the floor' were more stressful than other operations. Postural workloads on the trunk and head were greater in the tethering system than in the loose-housing systems due to differences in implements, the working height, and the working distance. PMID:20427034
Hwang, Jaejin; Kong, Yong-Ku; Jung, Myung-Chul
A 3-yr study evaluated the carryover effects of dairy heifer grazing experience on behavior and first lactation performance as dairy cows. Forty-one Holstein and 23 Holstein-Jersey crossbred calves born between January and April 2008 were randomly assigned to one of four treatments (PP, PC, CP and C...
It is well documented that global warming is unequivocal. Dairy production systems are considered as important sources of greenhouse gas emissions; however, little is known about the sensitivity and vulnerability of these production systems themselves to climate warming. This review brings different aspects of dairy cow production in Central Europe into focus, with a holistic approach to emphasize potential future consequences and challenges arising from climate change. With the current understanding of the effects of climate change, it is expected that yield of forage per hectare will be influenced positively, whereas quality will mainly depend on water availability and soil characteristics. Thus, the botanical composition of future grassland should include species that are able to withstand the changing conditions (e.g. lucerne and bird's foot trefoil). Changes in nutrient concentration of forage plants, elevated heat loads and altered feeding patterns of animals may influence rumen physiology. Several promising nutritional strategies are available to lower potential negative impacts of climate change on dairy cow nutrition and performance. Adjustment of feeding and drinking regimes, diet composition and additive supplementation can contribute to the maintenance of adequate dairy cow nutrition and performance. Provision of adequate shade and cooling will reduce the direct effects of heat stress. As estimated genetic parameters are promising, heat stress tolerance as a functional trait may be included into breeding programmes. Indirect effects of global warming on the health and welfare of animals seem to be more complicated and thus are less predictable. As the epidemiology of certain gastrointestinal nematodes and liver fluke is favourably influenced by increased temperature and humidity, relations between climate change and disease dynamics should be followed closely. Under current conditions, climate change associated economic impacts are estimated to be neutral if some form of adaptation is integrated. Therefore, it is essential to establish and adopt mitigation strategies covering available tools from management, nutrition, health and plant and animal breeding to cope with the future consequences of climate change on dairy farming. PMID:23253935
Gauly, M; Bollwein, H; Breves, G; Brügemann, K; Dänicke, S; Da?, G; Demeler, J; Hansen, H; Isselstein, J; König, S; Lohölter, M; Martinsohn, M; Meyer, U; Potthoff, M; Sanker, C; Schröder, B; Wrage, N; Meibaum, B; von Samson-Himmelstjerna, G; Stinshoff, H; Wrenzycki, C
This cross-sectional study examined various aspects of cubicle design and management in terms of their potential as risk factors for hock lesions, using an epidemiological approach. Cubicle dairy farms in Germany and Austria with Holstein Friesian or Simmental cows were visited during the winter housing season. 105 farms and 3691 cows were included in the analysis which consisted of three steps: bifactorial regression, regression trees and multiple linear regression. The mean farm prevalence of hock lesions, i.e. scabs, wounds, and swellings was 50%, with a range from 0 to 100%. The final model contained eight factors which were largely related to lying comfort and explained 75% of the variance. The presence of a curb turned out to be the most influential beneficial factor. Additionally, there were fewer hock lesions when cows were housed with deep bedded cubicles compared to cubicles without deep bedding. Other factors in the regression model were softness and length of the lying surface and height of free space under cubicle partitions, the proportion of overconditioned cows and a variable encoding three different combinations of region, husbandry system (organic and conventional) and breed. Independently from the risk factor model hock lesions were positively correlated with lameness at herd level as well as at animal level. This probably results from related risk factors for both conditions. It can be concluded that lying comfort of dairy cows should be improved in order to prevent hock lesions. In addition, preventive measures for hock lesions at the same time have a potential of reducing lameness and thus to improve cow welfare in several aspects. PMID:23174217
Brenninkmeyer, Christine; Dippel, Sabine; Brinkmann, Jan; March, Solveig; Winckler, Christoph; Knierim, Ute
Ruminant production systems have been facing the sustainability challenge, namely, how to maintain or even increase production while reducing their environmental footprint, and improving social acceptability. One currently discussed option is to encourage farmers to follow agroecological principles, that is, to take advantage of ecological processes to reduce inputs and farm wastes, while preserving natural resources, and using this diversity to increase system resilience. However, these principles need to be made more practical. Here, we present the procedure undertaken for the collaborative construction of an agroecological diagnostic grid for dairy systems with a focus on the mountain farming relying on the use of semi-natural grasslands. This diagnosis will necessarily rely on a multicriteria evaluation as agroecology is based on a series of complementary principles. It requires defining a set of criteria, based on practices to be recommended, that should be complied with to ensure agroecological production. We present how such agroecological criteria were identified and organized to form the architecture of an evaluation model. As a basis for this work, we used five agroecological principles already proposed for animal production systems. A group of five experts of mountain production systems and of their multicriteria evaluation was selected, with a second round of consultation with five additional experts. They first split up each principle into three to four generic sub-principles. For each principle, they listed three to eight categories of state variables on which the fulfilment of the principle should have a positive impact (e.g. main health disorders for the integrated health management principle). State variables are specific for a given production, for example, dairy farms. Crossing principles with state variables enabled experts to build five matrices, with 75 cells relevant for dairy systems. In each cell, criteria are specific to the local context, for example, mountain dairy systems in this study. Finally, we discuss the opportunities offered by our methodology, and the steps remaining for the construction of the evaluation model. PMID:24780586
Botreau, R; Farruggia, A; Martin, B; Pomiès, D; Dumont, B
Control over the quantity and quality of food ingested by grazing ruminants in temperate pasture systems remains elusive. This is due in part to the foraging choices that animals make when grazing from communities of mixed plant species. Grazing behavior and intake interact strongly with the feed supply-demand balance, pasture com- position, and grazing method. These interactions are not completely
D. F. Chapman; A. J. Parsons; G. P. Cosgrove; D. J. Barker; D. M. Marotti; K. J. Venning; S. M. Rutter; J. Hill; A. N. Thompson
The efficiency of milk production in pasture-based systems is heavily influenced by calving pattern, necessitating excellent reproductive performance in a short-breeding season. Where grazed pasture is the major component of the diet, cows are underfed relative to their intake potential. The cow responds by reducing milk output, but fertility is generally better than high intake confinement systems that achieve greater milk production per cow. A number of studies have identified body condition score (BCS) measurements that are related to likelihood of both submission and conception. Blood metabolites and metabolic hormones linked to fertility outcomes are now well characterized. In general, fertility variables have favourable associations with circulating concentrations of glucose, insulin and IGF-1 and unfavourable associations with non-esterified fatty acids, ?-hydroxybutyrate and endogenous growth hormone. Nutritional strategies to impact these metabolic indicators have been utilized, but effects on herd fertility are inconsistent. Simply supplementing cows with additional energy in the form of standard concentrates does not appear to have a pronounced effect on fertility. Energy from additional concentrates fed during lactation is preferentially partitioned towards extra milk production rather than BCS repletion. The higher the genetic merit for milk production, the greater the partitioning of additional nutrients to the mammary gland. This review outlines the unique nutritional challenges of pasture-based systems, the role of specific metabolic hormones and metabolites in regulating reproductive function, and nutritional strategies to improve herd fertility. PMID:24844127
Butler, S T
Life cycle assessment (LCA) and life cycle costing (LCC) are used to investigate integrated algae bioenergy production and nutrient management on small dairy farms. Four cases are considered: a reference land-application scenario (REF), anaerobic digestion with land-application of liquid digestate (AD), and anaerobic digestion with recycling of liquid digestate to either an open-pond algae cultivation system (OPS) or an algae turf scrubber (ATS). LCA indicates that all three "improved" scenarios (AD, OPS, and ATS) are environmentally favorable compared to REF, exhibiting increases in net energy output up to 854GJ/yr, reductions in net eutrophication potential up to 2700kg PO(4)-eq/yr, and reductions in global warming potential up to 196Mg CO(2)-eq/yr. LCC reveals that the integrated algae systems are much more financially attractive than either AD or REF, whereby net present values (NPV) are as follows: $853,250 for OPS, $790,280 for ATS, -$62,279 for REF, and -$211,126 for AD. However, these results are highly dependent on the sale price for nutrient credits. Comparison of LCA and LCC results indicates that robust nutrient credit markets or other policy tools are required to align financial and environmental preferability of energy production systems and foster widespread adoption of sustainable nutrient management systems. PMID:23313697
Zhang, Yongli; White, Mark A; Colosi, Lisa M
Respiratory disease of young dairy calves is a significant cause of morbidity, mortality, economic loss, and animal welfare concern but there is no gold standard diagnostic test for antemortem diagnosis. Clinical signs typically used to make a diagnosis of respiratory disease of calves are fever, cough, ocular or nasal discharge, abnormal breathing, and auscultation of abnormal lung sounds. Unfortunately, routine screening of calves for respiratory disease on the farm is rarely performed and until more comprehensive, practical and affordable respiratory disease-screening tools such as accelerometers, pedometers, appetite monitors, feed consumption detection systems, remote temperature recording devices, radiant heat detectors, electronic stethoscopes, and thoracic ultrasound are validated, timely diagnosis of respiratory disease can be facilitated using a standardized scoring system. We have developed a scoring system that attributes severity scores to each of four clinical parameters; rectal temperature, cough, nasal discharge, ocular discharge or ear position. A total respiratory score of five points or higher (provided that at least two abnormal parameters are observed) can be used to distinguish affected from unaffected calves. This can be applied as a screening tool twice-weekly to identify pre-weaned calves with respiratory disease thereby facilitating early detection. Coupled with effective treatment protocols, this scoring system will reduce post-weaning pneumonia, chronic pneumonia, and otitis media. PMID:25410122
McGuirk, Sheila M; Peek, Simon F
This publication explains the factors affecting livestock grazing distribution and discusses ways to improve it. It also reports the results of a study that used Global Positioning System collars to pinpoint the movement of cattle on various...
Lyons, Robert K.; Machen, Richard V.
20 TemPerature . ~ . e? ~ e a a ~ ~ ~ * e ~ ~ e e Soils in Relation to Grazing Area Utilization Measurements ~ a e 4 ~ ~ a a 4 a ~ e a SUMMARY AHD CO'NCLDS IOE ~ ~ ~ a a ~ ~ ~ ~ ~ ~ a ~ a LITFkl %TURF CITED ~ a e ~ ~ a e ~ e e e ~ e a ~ ~ e ~ e... of periods of cattle activities on warm and hot days . . ~ . 40 Percent grazing time in relation to percent of various so11 series in observed P3 St'urea ~ e o ~ ~ ~ o o ~ ~ ~ ~ ~ e e ~ ~ ~ e e ~l Average percentage of' turf', tobosa and v1ne mesquite...
Wright, John Allen
Principles of grazing management center round the temporal and spatial distribution of various kinds and number of livestock. Within the context of this chapter, management of grazing or browsing will be characterized in terms of intensity, method, and season (timing), and as a function of the type ...
A study to examine factors that influence dairy cattle fertility was conducted in the United Kingdom (UK) and Malawi. Productivity data from the UK comprising 56,014 records from 574 Holstein cows were retrieved from ...
Banda, Liveness Jessica
A five-year Coordinated Research Project (CRP) entitled ‘Integrated approach for improving small scale market oriented dairy\\u000a systems’ is currently being implemented by the Food and Agriculture Organization and the International Atomic Energy Agency,\\u000a through their Joint Programme on ‘Nuclear Techniques in Food and Agriculture’. The objectives are to (a) identify and prioritize\\u000a the constraints and opportunities in the selected dairy
B. M. A. O. Perera
Our goal is to characterize and monitor feedbacks between innovative insurance products and ecosystem services in resource poor environments. Our team is integrating longitudinal field-based measurements and monitoring protocols to quantify grazing animal impact related to the implementation of an ...
The main objective of this research is to quantify the effect of grazing management practices and vegetative filter strips (VFS) on losses of total suspended solids (TSS), nitrate-nitrogen (NO3-N), ortho-phosphorus (PO4-P) and total P (TP) in surface runoff during natural rainfall events. The data ...
of dairy waste management practices. The results of these studies will aid producers, engineers, planners, and regulatory officials in the refinement and adoption of appropriate practices for water quality protection....
Sweeten, John M.; Wolfe, Mary Leigh
Improved pasture management systems are needed to restore soil quality, sequester soil organic C, and build the productive capacity of soils in grassland environments so that (1) precipitation can be effectively utilized by plants, (2) water runoff and contaminant transport can be minimized, (3) nat...
A longitudinal descriptive study was conducted to determine the prevalence and distribution of flukes (Fasciola gigantica and amphistomes) on traditional, large-scale and small-scale dairy cattle farms in Iringa district, southern highlands of Tanzania. Coprological examinations of different cohorts for the presence of fluke eggs were recorded monthly. Results indicated a significant influence of the type of management on the prevalence of both Fasciola and amphistomes. The prevalence of flukes was highest in the traditional system, moderate in the large-scale dairy system and lowest in the small-scale dairy system in most parts of the year. Adults and yearlings had the highest prevalence of flukes in all management systems throughout the year. The proportion of animals excreting amphistome eggs was always higher than that of animals excreting Fasciola eggs in all zones, villages, management systems, farms and age groups. The proportion of animals passing fluke eggs increased gradually from the early dry season and peaked at the end of the dry season and the early part of the rainy season. Strategic treatments against flukes are recommended in adults and yearlings only in traditional and large-scale dairy farms. Routine treatments of calves/weanlings in large-scale and traditional farms and zero-grazed small-scale dairy cattle farms might be unnecessary. For a cost-effective helminth control programme in the area, strategic treatments at the beginning of the dry season (June) and at the end of the dry/early rainy season (November/December) are recommended. PMID:15934638
Keyyu, J D; Monrad, J; Kyvsgaard, N C; Kassuku, A A
Developing machine learning and soft computing techniques has provided many opportunities for researchers to establish new analytical methods in different areas of science. The objective of this study is to investigate the potential of two types of intelligent learning methods, artificial neural networks and neuro-fuzzy systems, in order to estimate breeding values (EBV) of Iranian dairy cattle. Initially, the breeding values of lactating Holstein cows for milk and fat yield were estimated using conventional best linear unbiased prediction (BLUP) with an animal model. Once that was established, a multilayer perceptron was used to build ANN to predict breeding values from the performance data of selection candidates. Subsequently, fuzzy logic was used to form an NFS, a hybrid intelligent system that was implemented via a local linear model tree algorithm. For milk yield the correlations between EBV and EBV predicted by the ANN and NFS were 0.92 and 0.93, respectively. Corresponding correlations for fat yield were 0.93 and 0.93, respectively. Correlations between multitrait predictions of EBVs for milk and fat yield when predicted simultaneously by ANN were 0.93 and 0.93, respectively, whereas corresponding correlations with reference EBV for multitrait NFS were 0.94 and 0.95, respectively, for milk and fat production. PMID:22991575
Shahinfar, Saleh; Mehrabani-Yeganeh, Hassan; Lucas, Caro; Kalhor, Ahmad; Kazemian, Majid; Weigel, Kent A.
Background Fungi are key dietary resources for many animals. Fungi, in consequence, have evolved sophisticated physical and chemical defences for repelling and impairing fungivores. Expression of such defences may entail costs, requiring diversion of energy and nutrients away from fungal growth and reproduction. Inducible resistance that is mounted after attack by fungivores may allow fungi to circumvent the potential costs of defence when not needed. However, no information exists on whether fungi display inducible resistance. We combined organism and fungal gene expression approaches to investigate whether fungivory induces resistance in fungi. Methodology/Principal Findings Here we show that grazing by larval fruit flies, Drosophila melanogaster, induces resistance in the filamentous mould, Aspergillus nidulans, to subsequent feeding by larvae of the same insect. Larval grazing triggered the expression of various putative fungal resistance genes, including the secondary metabolite master regulator gene laeA. Compared to the severe pathological effects of wild type A. nidulans, which led to 100% insect mortality, larval feeding on a laeA loss-of-function mutant resulted in normal insect development. Whereas the wild type fungus recovered from larval grazing, larvae eradicated the chemically deficient mutant. In contrast, mutualistic dietary yeast, Saccharomyces cerevisiae, reached higher population densities when exposed to Drosophila larval feeding. Conclusions/Significance Our study presents novel evidence that insect grazing is capable of inducing resistance to further grazing in a filamentous fungus. This phenotypic shift in resistance to fungivory is accompanied by changes in the expression of genes involved in signal transduction, epigenetic regulation and secondary metabolite biosynthesis pathways. Depending on reciprocal insect-fungus fitness consequences, fungi may be selected for inducible resistance to maintain high fitness in fungivore-rich habitats. Induced fungal defence responses thus need to be included if we wish to have a complete conception of animal-fungus co-evolution, fungal gene regulation, and multitrophic interactions. PMID:24023705
Caballero Ortiz, Silvia; Trienens, Monika; Rohlfs, Marko
Florida dairies need year-round forage systems that prevent loss of N to ground water from waste effluent sprayfields. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentrations in soil water below the rooting zone for two forage systems during four 12-mo cycles (1996-2000). Soil in the sprayfield is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzipsamment). Over four cycles, average loading rates of effluent N were 500, 690, and 910 kg ha(-1) per cycle. Nitrogen removed by the bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (BR) during the first three cycles was 465 kg ha(-1) per cycle for the low loading rate, 528 kg ha(-1) for the medium rate, and 585 kg ha(-1) for the high. For the corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye system (CSR), N removals were 320 kg ha(-1) per cycle for the low rate, 327 kg ha(-1) for the medium, and 378 kg ha(-1) for the high. The higher N removals for BR were attributed to higher N concentration in bermudagrass (18.1-24.2 g kg(-1)) than in corn and forage sorghum (10.3-14.7 g kg(-1)). Dry matter yield declined in the fourth cycle for bermudagrass but N removal continued to be higher for BR than CSR. The BR system was much more effective at preventing NO3(-)-N leaching. For CSR, NO3(-)-N levels in soil water (1.5 m below surface) increased steeply during the period between the harvest of one forage and canopy dosure of the next. Overall, the BR system was better than CSR at removing N from the soil and maintaining low NO3(-)-N concentrations below the rooting zone. PMID:12469848
Woodard, Kenneth R; French, Edwin C; Sweat, Lewin A; Graetz, Donald A; Sollenberger, Lynn E; Macoon, Bisoondat; Portier, Kenneth M; Wade, Brett L; Rymph, Stuart J; Prine, Gordon M; Van Horn, Harold H
Fasciolosis caused by Fasciola hepatica is responsible for major production losses in cattle farms. The objectives of this study were to assess the effect of farm management practices on liver fluke prevalence on Irish dairy farms and to document the current control measures against parasitic diseases. In total, 369 dairy farms throughout Ireland were sampled from October to December 2013, each providing a single bulk tank milk (BTM) sample for liver fluke antibody-detection ELISA testing and completing a questionnaire on their farm management. The analysis of samples showed that cows on 78% (n=288) of dairy farms had been exposed to liver fluke. There was a difference (P<0.05) between farms where cows were positive or negative for liver fluke antibodies in (a) the total number of adult dairy cows in herds, (b) the number of adult dairy cows contributing to BTM samples, and (c) the size of the total area of grassland, with positive farms having larger numbers in each case. There was no difference (P>0.05) between positive and negative farms in (a) the grazing of dry cows together with replacement cows, (b) whether or not grazed grassland was mowed for conservation, (c) the type of drinking water provision system, (d) spreading of cattle manure on grassland or (e) for grazing season length (GSL; mean=262.5 days). Also, there were differences (P<0.001) between drainage statuses for GSL with farms on good drainage having longer GSL than moderately drained farms. The GSL for dairy cows on farms with good drainage was 11 days longer than for those with moderate drainage (P<0.001). The percentage of farmers that used an active ingredient during the non-lactating period against liver fluke, gastrointestinal nematodes, lungworm, and rumen fluke was 96%, 85%, 77% and 90%, respectively. Albendazole was the most frequently used active ingredient for treatment against gastrointestinal nematodes (57%), liver fluke (40%) and lungworm (47%), respectively. There was a difference (P<0.05) in the use of triclabendazole and albendazole between positive and negative farms, with triclabendazole use being more common in positive farms. This study highlighted differences in dairy management practices between Irish farms with dairy herds exposed or not exposed to liver fluke and stressed the need of fine-scale mapping of the disease patterns even at farm level to increase the accuracy of risk models. Also, comprehensive advice and professional support services to farmers on appropriate farm management practices are very important for an effective anthelmintic control strategy. PMID:25591405
Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo
Waste stabilization pond systems are widely used to treat animal wastes under highly variable hydraulic loading regimes. These systems have received limited research attention with regard to their hydrodynamic behaviour and the potential impact of shock hydraulic loading on their performance. In this study a two-stage dairy shed waste stabilisation pond system was topographically surveyed to determine the physical shape and the theoretical hydraulic retention time (HRT) of each pond, as well as the extent of sludge accumulation in the primary pond. The primary pond was then subjected to a series of drogue tracking runs whereby weighted floating survey targets with submerged 'sails' were tracked during their movement through the pond at times of peak flow in order to characterise the hydrodynamic behaviour of the pond. The full capacity volumes of the primary and secondary ponds were calculated to be 1285 m3 and 2391 m3, respectively. Sludge had been accumulating in the primary pond at a rate of 0.73 m3/d over a period of 2.4 years and this has reduced the active treatment volume of the pond to 657 m3. Based on mean outflow, the HRTs of the ponds were 40 d and 137 d, respectively. The drogue runs revealed a vortex-like mixing pattern within the pond with higher velocities around the perimeter of the pond between the inlet and outlet, and lower velocities in the centre of the pond. In-pond velocities seemed relatively high in comparison with those from other drogue studies of larger ponds and the surging inflow caused the formation of a flow 'jet' that potentially contributed to significant short-circuiting. The range of influence of this flow jet, however, was limited to within 15 m of the inlet, suggesting that short-circuiting would be likely to occur only under certain high inflow conditions. PMID:17591191
Fyfe, J; Smalley, J; Hagare, D; Sivakumar, M
Ruminant livestock turn forages and poor-quality feeds into human edible products, but enteric methane (CH4) emissions from ruminants are a significant contributor to greenhouse gases (GHGs) and hence to climate change. Despite the predominance of pasture-based beef production systems in many parts of Europe there are little data available regarding enteric CH4 emissions from free-ranging grazing cattle. It is possible that differences in physiology or behaviour could influence comparative emissions intensities for traditional and modern breed types depending on the nutritional characteristics of the herbage grazed. This study investigated the role of breed type in influencing CH4 emissions from growing beef steers managed on contrasting grasslands typical of intensive (lowland) and extensive (upland) production systems. Using the SF6 dilution technique CH4 emissions were estimated for a modern, fast-growing crossbred (Limousin cross) and a smaller and hardier native breed (Welsh Black) when grazing lowland perennial ryegrass (high nutritional density, low sward heterogeneity) and semi-improved upland pasture (low/medium nutritional density, high sward heterogeneity). Live-weight gain was substantially lower for steers on the upland system compared to the lowland system (0.31 vs. 1.04 kg d?1; s.e.d.?=?0.085 kg d?1; P<0.001), leading to significant differences in estimated dry matter intakes (8.0 vs. 11.1 kg DM d?1 for upland and lowland respectively; s.e.d.?=?0.68 kg DM d?1; P<0.001). While emissions per unit feed intake were similar for the lowland and upland systems, CH4 emissions per unit of live-weight gain (LWG) were substantially higher when the steers grazed the poorer quality hill pasture (760 vs 214 g kg?1 LWG; s.e.d.?=?133.5 g kg?1 LWG; P<0.001). Overall any effects of breed type were relatively small relative to the combined influence of pasture type and location. PMID:25259617
Fraser, Mariecia D.; Fleming, Hannah R.; Moorby, Jon M.
We report measurements of methane emissions from individual ruminant livestock-both sheep and dairy cows-grazing pasture typical of New Zealand lowlands in the temperate southwest Pacific. These are the first measurements reported from grazing sheep, and among the first from grazing cattle. The measurement technique, developed at Washington State University, enables emission rates to be determined from analyses of "breath" samples collected while grazing. More than 250 measurements of daily methane emission from 50 sheep (8 months old) were made, with flock-mean emission 18.9 ± 0.8 g hd -1 d -1. Although emissions were weakly correlated with feed intake, they represented a 4.6 ± 0.1 % average loss of gross dietary energy. The corresponding mean emission based on 40 measurements of daily emissions from 10 lactating dairy cows was 263 ± 10 g hd -1 d -1, approximately 6.2% of estimated gross energy intake. A notable feature was the large inter-sheep variability in daily methane emission (factor of 1.4 range) that could not be attributed to variable intake. This would appear to suggest an appreciable diversity of methanogenetic response to digestion, and may be significant in the search for strategies to control emissions of this greenhouse gas.
Lassey, Keith R.; Ulyatt, Marcus J.; Martin, Ross J.; Walker, Carolyn F.; David Shelton, I.
LtBRARY A A M COLLEGE OF TEXAS THE EFFECT OF GRAZING MANAGEMENT SYSTEMS ON PERFORMATtCE OF BEEF ANIMALS AND ON THE YIELD AND CHEMICAL AND BOTANICAL COMPOSITION OF TEXAS COAST PRAIRIE PASTURES A Thesis Marvin Edmund Hiewe Submitted... ANIMALS AND ON THE YIELD AND CHEMICAL AND BOTANICAL COMPOSITION OF TEXAS COAST PRAIRIE PASTVRES A Thesis by Marvin Edmund Riewe Approved as to style and content bye (Chairman of Committee Head of Department) January', 1959 & I I A I cn P I...
Riewe, Marvin Edmund
There is increasing concern that the intensification of dairy production reduces the concentrations of nutritionally desirable compounds in milk. This study therefore compared important quality parameters (protein and fatty acid profiles; ?-tocopherol and carotenoid concentrations) in milk from four dairy systems with contrasting production intensities (in terms of feeding regimens and milking systems). The concentrations of several nutritionally desirable compounds (?-lactoglobulin, omega-3 fatty acids, omega-3/omega-6 ratio, conjugated linoleic acid c9t11, and/or carotenoids) decreased with increasing feeding intensity (organic outdoor ? conventional outdoor ? conventional indoors). Milking system intensification (use of robotic milking parlors) had a more limited effect on milk composition, but increased mastitis incidence. Multivariate analyses indicated that differences in milk quality were mainly linked to contrasting feeding regimens and that milking system and breed choice also contributed to differences in milk composition between production systems. PMID:22737968
Stergiadis, Sokratis; Leifert, Carlo; Seal, Chris J; Eyre, Mick D; Nielsen, Jacob H; Larsen, Mette K; Slots, Tina; Steinshamn, Håvard; Butler, Gillian
Background There is considerable interest in dairy products from low-input systems, such as mountain-pasture grazing cows, because these products are believed to be healthier than products from high-input conventional systems. This may be due to a higher content of bioactive components, such as phytanic acid, a PPAR-agonist derived from chlorophyll. However, the effects of such products on human health have been poorly investigated. Objective To compare the effect of milk-fat from mountain-pasture grazing cows (G) and conventionally fed cows (C) on risk markers of the metabolic syndrome. Design In a double-blind, randomized, 12-week, parallel intervention study, 38 healthy subjects replaced part of their habitual dietary fat intake with 39 g fat from test butter made from milk from mountain-pasture grazing cows or from cows fed conventional winter fodder. Glucose-tolerance and circulating risk markers were analysed before and after the intervention. Results No differences in blood lipids, lipoproteins, hsCRP, insulin, glucose or glucose-tolerance were observed. Interestingly, strong correlations between phytanic acid at baseline and total (P<0.0001) and LDL cholesterol (P=0.0001) were observed. Conclusions Lack of effects on blood lipids and inflammation indicates that dairy products from mountain-pasture grazing cows are not healthier than products from high-input conventional systems. Considering the strong correlation between LDL cholesterol and phytanic acid at baseline, it may be suggested that phytanic acid increases total and LDL cholesterol. Trial registration ClinicalTrials.gov, NCT01343589 PMID:23842081
Our objective was to compare health and welfare of dairy cows kept in three types of husbandry systems: (1) tie stalls with regular exercise in summer but minimal outdoor access during winter (the reference level for analyses); (2) tie stalls with regular exercise in an exercise yard or pasture throughout the year; (3) loose-housing with regular access to an outdoor exercise yard or pasture. A total of 134 farms were visited (two to) three times in two years. Cows were examined for lameness, skin alterations at the hock joints, scars or injuries at the teats, and skin injuries at other locations. Lying and standing-up behavior were also evaluated. Farmers were requested to record the incidence of medical treatments for the whole observation period. A multivariable logistic-regression analysis was performed for each indicator of health and welfare with husbandry type, aspects of the housing system, farm characteristics, and management routines as the predictor variables. For welfare indicators recorded on individual animals, regression was performed correcting for clustering of observations within herds by Generalized Estimation Equation. Risk factors for the incidence of medical treatments were analyzed in a negative-binomial regression model. The odds for lameness were reduced for tie stalls with regular exercise throughout the year (OR=0.7). The prevalence of alterations at the hock joints was lower in loose-housing with regular outdoor exercise (OR=0.4). Teat injuries were less frequent in loose-housing with regular outdoor exercise (OR=0.1) and tie stalls with regular exercise (OR=0.4). Farms with loose-housing and regular outdoor exercise had a lower incidence of medical treatments (IR=0.6) than reference level farms. PMID:15579346
Regula, G; Danuser, J; Spycher, B; Wechsler, B
This task-based curriculum guide for agricultural production, specifically for dairy livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…
Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.
Field trials were carried out between 2002 and 2005 to investigate the effects of biogas digestion in a mixed organic dairy\\u000a farming system with arable land and grassland on nutrient cycling, nitrogen (N) uptake and crop yields within a cropping system\\u000a comprising a whole crop rotation. Five treatments were carried out: (i) solid farmyard manure, (ii) undigested liquid slurry,\\u000a (iii)
Kurt Möller; Walter Stinner; Arno Deuker; Günter Leithold
The objective of this review paper was to summarise the latest findings in dairy cattle reproductive economics with an emphasis on high yielding, confined total mixed ration systems. The economic gain increases as the reproductive efficiency improves. These increments follow the law of diminishing returns, but are still positive even at high reproductive performance. Reproductive improvement results in higher milk productivity and, therefore, higher milk income over feed cost, more calf sales and lower culling and breeding expenses. Most high-yielding herds in the United States use a combination of timed artificial insemination (TAI) and oestrous detection (OD) reproductive programme. The ratio of achievable pregnancies between OD and TAI determines the economic value difference between both and their combinations. Nonetheless, complex interactions between reproductive programme, herd relative milk yield, and type of reproductive programme are reported. For example, higher herd relative milk yield would favour programme relying more on TAI. In addition, improved reproductive efficiency produces extra replacements. The availability of additional replacements could allow more aggressive culling policies (e.g. less services for non-pregnant cows) to balance on-farm supply and demand of replacements. Balancing heifer replacement availability in an efficient reproductive programme brings additional economic benefits. New technologies such as the use of earlier chemical tests for pregnancy diagnosis could be economically effective depending on the goals and characteristics of the farm. Opportunities for individual cow reproductive management within defined reproductive programme exist. These decisions would be based on economic metrics derived from the value of a cow such as the value of a new pregnancy, the cost of a pregnancy loss, or the cost of an extra day open. PMID:24679357
Cabrera, V E
Quantifying the long term environmental impacts of dairy and beef production is complex due to the many interactions among the physical and biological components of farms that affect the amount and type of emissions that occur. Emissions are influenced by climate and soil characteristics as well as ...
Increased corn silage and manure production accompanying the proliferation of large dairies has prompted concern regarding their environmental impacts. Our objectives were (1) to quantify soil chemical properties and offsite nutrient transport under field-scale corn (Zea mays L.) silage production a...
Greenhouse gas (GHG) emissions and their potential impact on the environment has become an important national and international concern. Dairy production, along with all other types of animal agriculture, is a recognized source of GHG emissions, but little information exists on the net emissions fro...
Data on accumulated life performance of crosses of Ayrshire (A), Brown Swiss (B), Friesian (F) and Sahiwal (S) cattle collected over a 21-year period from a dairy ranch in the lowland tropics of Kenya were analysed to estimate additive and non-additive genetic effects on economic traits. These were used to predict and compare, first, performance of cows under nine crossbreeding
A. K. Kahi; W. Thorpe; G. Nitter; J. A. M. Van Arendonk; C. F. Gall
An Economic Opportunity Survey was conducted on dairy farms in the North West Province of Cameroon. Results showed that median (range) number of cows in milk per farm was zero point six (0-4) and six (3-12) in the zero grazing and transhumance systems, respectively. Medians (range) of three (0-24) and four (3-10) litres of milk were sold per farm per day, corresponding to 30% and 60% of milk produced. 24% and 13% of total cattle per herd were milking cows in the zero grazing and transhumance systems respectively. Median milk production per cow on one day was two (0-25) and two (1-3) litres. Median calf production interval was 14.5 (12-25) and. 21.5 (14-29) months. More milk produced per day represented the best economic opportunity in both systems while reduced age at first calving and longer lactation length were the next in both. Wastage of milk through spoilage from poor hygiene and lack of cooling was a major problem. Holstein cows, which were in the zero grazing system, had unexpectedly short lactations. Constraints identified led to the setting up of interventions of training and advice for farmers and of better nutrition. PMID:18265867
Bayemi, P H; Webb, E C; Manjeli, Y; Naoussi, P
U.S. organic dairy production has increased to meet demand for organic milk. Organic dairy farmers have come under increasing financial stress due to increases in concentrated feed prices. Organic dairies in the Northeast U.S. have experimented with different forage and grain crops to maximize on-fa...
A study was conducted to evaluate the effect of forage species and sward structure of dairy cows grazing micro-swards. Cows were offered one of the four grasses planted in experimental micro-sward boxes over two years. Grass species consisted of: orchardgrass (Dactylis glomerata L.), meadow fescue ...
The objective of this study was to validate an electronic system for monitoring individual feeding behavior and feed intake (Intergado Ltd., Contagem, Minas Gerais, Brazil) in freestall-housed dairy cattle. No data have been published that validate either the behavioral measurement or the feed intake of this system. Feeding behavior data were recorded for 12 Holstein cows over 5d using an Intergado system and time-lapse video. The cows were fitted with an ear tag containing a unique passive transponder and provided free access to 12 feed bins. The system documented the visit duration and feed intake by recording the animal identification number, bin number, initial and final times, and the difference between feed weight at start and end of each feed bin visit. These data were exported to Intergado web software and reports were generated. Electronic data on animal behavior were compared with video data collected during the same evaluation period. An external scale was used to manually measure and validate the electronic system's ability to monitor dairy cow feed intake for each feed bin visit. The feed intake was manually measured for 4-h time periods and compared with the sum of the feed intake recorded by the monitoring system for each cow visit during the same time period. Video and manual weight data were regressed on the electronic feeding behavior and feeding intake data to evaluate the precision of the monitoring system. The Intergado system presented high values for specificity (99.9%) and sensitivity (99.6%) for cow detection. The visit duration and feed intake per visit collected using the electronic monitoring system were similar to the video and manual weighing data, respectively. The difference between the feed intake measured manually and the sum of the electronically recorded feed intake was less than 250g (25,635±2,428 and 25,391±2,428g estimated using manual weighing and the electronic system, respectively). In conclusion, the Intergado system is a reasonable tool to monitor feeding behavior and feed intake for freestall-housed dairy cows. PMID:25771061
Chizzotti, M L; Machado, F S; Valente, E E L; Pereira, L G R; Campos, M M; Tomich, T R; Coelho, S G; Ribas, M N
by the Texas State Soil and Water Conservation Board (TSSWCB) for reducing water pollution associated with dairy animal production systems. As part of this demonstration, the efficacy of a prospective new technology (i.e.L4DB® microbial treatment system...
Mukthar, S.; Rahman, S.; Gregory, L.
A life cycle assessment (LCA) of dairy systems in Nova Scotia was conducted to compare environmental impacts of typical pasture and confinement operations. Data on material and energy inputs and outputs of these systems were obtained from local researchers and industry, and life cycle impacts in 11 categories were quantified. Use of concentrate feeds, N fertilizers, transport fuels and electricity
Nicole Arsenault; Peter Tyedmers; Alan Fredeen
In 1991, Terminology for Grazing Lands and Grazing Animals was published with the objective of ‘developing a consensus of clear definitions of terms used in the grazing of animals.’ During the XVIII International Grassland Congress, held in Canada in 1997, a new Terminology working group was formed ...
The dairy_wa.zip file is a zip file containing an Arc/Info export file and a text document. Note the DISCLAIM.TXT file as these data are not verified. Map extent: statewide. Input Source: Address database obtained from Wa Dept of Agriculture. Data was originally developed und...
Identifying the factors that determine the carbon source/sink strength of ecosystems is important for reducing uncertainty in the global carbon cycle. Arid grassland ecosystems are a widely distributed biome type in Xinjiang, Northwest China, covering approximately one-fourth the country's land surface. These grasslands are the habitat for many endemic and rare plant and animal species and are also used as pastoral land for livestock. Using the modified Biome-BGC grazing model, we modeled carbon dynamics in Xinjiang for grasslands that varied in grazing intensity. In general, this regional simulation estimated that the grassland ecosystems in Xinjiang acted as a net carbon source, with a value of 0.38 Pg C over the period 1979-2007. There were significant effects of grazing on carbon dynamics. An over-compensatory effect in net primary productivity (NPP) and vegetation carbon (C) stock was observed when grazing intensity was lower than 0.40 head/ha. Grazing resulted in a net carbon source of 23.45 g C m-2 yr-1, which equaled 0.37 Pg in Xinjiang in the last 29 years. In general, grazing decreased vegetation C stock, while an increasing trend was observed with low grazing intensity. The soil C increased significantly (17%) with long-term grazing, while the soil C stock exhibited a steady trend without grazing. These findings have implications for grassland ecosystem management as it relates to carbon sequestration and climate change mitigation, e.g., removal of grazing should be considered in strategies that aim to increase terrestrial carbon sequestrations at local and regional scales. One of the greatest limitations in quantifying the effects of herbivores on carbon cycling is identifying the grazing systems and intensities within a given region. We hope our study emphasizes the need for large-scale assessments of how grazing impacts carbon cycling. Most terrestrial ecosystems in Xinjiang have been affected by disturbances to a greater or lesser extent in the past several decades (e.g., land-use change, timber exploitation, and air pollution). However, regional evaluations that account for all of the local disturbances have been difficult. Data from field measurements play a pivotal role in comparing model simulations with observations.
Luo, Geping; Han, Qifei; Li, Chaofan; Yang, Liao
? Early in life, animals learn what to eat and what to avoid from older animals grazing with them. The strongest learning bond occurs between the mother and offspring. Learning from the mother begins during gesta- tion with exposure to flavors through... amniotic fluid and continues following birth from tasting mother?s milk. Animals also learn from experience. Grazing animals tend to sample new forages in small quantities. If an ani- mal becomes sick from eating a new food, it will either avoid that food...
Lyons, Robert K.; Machen, Richard V.
The objective of this review was to describe, compare and evaluate agreement, reliability, and validity of manual and automatic locomotion scoring systems (MLSSs and ALSSs, respectively) used in dairy cattle lameness research. There are many different types of MLSSs and ALSSs. Twenty-five MLSSs were found in 244 articles. MLSSs use different types of scale (ordinal or continuous) and different gait and posture traits need to be observed. The most used MLSS (used in 28% of the references) is based on asymmetric gait, reluctance to bear weight, and arched back, and is scored on a five-level scale. Fifteen ALSSs were found that could be categorized according to three approaches: (a) the kinetic approach measures forces involved in locomotion, (b) the kinematic approach measures time and distance of variables associated to limb movement and some specific posture variables, and (c) the indirect approach uses behavioural variables or production variables as indicators for impaired locomotion. Agreement and reliability estimates were scarcely reported in articles related to MLSSs. When reported, inappropriate statistical methods such as PABAK and Pearson and Spearman correlation coefficients were commonly used. Some of the most frequently used MLSSs were poorly evaluated for agreement and reliability. Agreement and reliability estimates for the original four-, five- or nine-level MLSS, expressed in percentage of agreement, kappa and weighted kappa, showed large ranges among and sometimes also within articles. After the transformation into a two-level scale, agreement and reliability estimates showed acceptable estimates (percentage of agreement ? 75%; kappa and weighted kappa ? 0.6), but still estimates showed a large variation between articles. Agreement and reliability estimates for ALSSs were not reported in any article. Several ALSSs use MLSSs as a reference for model calibration and validation. However, varying agreement and reliability estimates of MLSSs make a clear definition of a lameness case difficult, and thus affect the validity of ALSSs. MLSSs and ALSSs showed limited validity for hoof lesion detection and pain assessment. The utilization of MLSSs and ALSSs should aim to the prevention and efficient management of conditions that induce impaired locomotion. Long-term studies comparing MLSSs and ALSSs while applying various strategies to detect and control unfavourable conditions leading to impaired locomotion are required to determine the usefulness of MLSSs and ALSSs for securing optimal production and animal welfare in practice. PMID:25000863
Schlageter-Tello, Andrés; Bokkers, Eddie A M; Koerkamp, Peter W G Groot; Van Hertem, Tom; Viazzi, Stefano; Romanini, Carlos E B; Halachmi, Ilan; Bahr, Claudia; Berckmans, Daniël; Lokhorst, Kees
Lameness poses a considerable problem in modern dairy farming. Several new developments (e.g., herd health plans) strive to help farmers improve the health and welfare of their herd. It was thus our aim to identify lameness risk factors common across regions, breeds, and farming systems for freestall-housed dairy cows. We analyzed data from 103 nonorganic and organic dairy farms in Germany and Austria that kept 24 to 145 Holstein Friesian or Fleckvieh cows in the milking herd (mean = 48). Data on housing, management, behavior, and lameness scores for a total of 3,514 cows were collected through direct observations and an interview. Mean lameness prevalence was 34% (range = 0-81%). Data were analyzed applying logistic regression with generalized estimating equations in a split-sample design. The final model contained 1 animal-based parameter and 3 risk factors related to lying as well as 1 nutritional animal-based parameter, while correcting for the significant confounders parity and data subset. Risk for lameness increased with decreasing lying comfort, that is, more frequent abnormal lying behavior, mats or mattresses used as a stall base compared with deep-bedded stall bases, the presence of head lunge impediments, or neck rail-curb diagonals that were too short. Cows in the lowest body condition quartile (1.25-2.50 for Holstein Friesian and 2.50-3.50 for Fleckvieh) had the highest risk of being lame. In cross-validation the model correctly classified 71 and 70% of observations in the model-building and validation samples, respectively. Only 2 out of 15 significant odds ratios (including contrasts) changed direction. They pertained to the 2 variables with the highest P-values in the model. In conclusion, lying comfort and nutrition are key risk areas for lameness in freestall-housed dairy cows. Abnormal lying behavior in particular proved to be a good predictor of lameness risk and should thus be included in on-farm protocols. The study is part of the European Commission's Welfare Quality project. PMID:19841210
Dippel, S; Dolezal, M; Brenninkmeyer, C; Brinkmann, J; March, S; Knierim, U; Winckler, C
Methodologies are required to verify agricultural greenhouse gas mitigation at scales relevant to farm management. Micrometeorological techniques provide a viable approach for comparing fluxes between fields receiving mitigation treatments and control fields. However, they have rarely been applied to spatially verifying treatments aimed at mitigating nitrous oxide emission from intensively grazed pastoral systems. We deployed a micrometeorological system to compare N2O flux among several ~1.5 ha plots in intensively grazed dairy pasture. The sample collection and measurement system is referred to as the Field-Scale Nitrous Oxide Mitigation Assessment System (FS-NOMAS) and used a tuneable diode laser absorption spectrometer to measure N2O gradients to high precision at four locations along a 300 m transect. The utility of the FS-NOMAS to assess mitigation efficacy depends largely on its ability to resolve very small vertical N2O gradients. The performance of the FS-NOMAS was assessed in this respect in laboratory and field-based studies. The FS-NOMAS could reliably resolve gradients of 0.039 ppb between a height of 0.5 and 1.0 m. The gradient resolution achieved corresponded to the ability to detect an inter-plot N2O flux difference of 26 ?g N2O-N m-2 h-1 under the most commonly encountered conditions of atmospheric mixing (quantified here by a turbulent transfer coefficient), but this ranged from 11 to 59 ?g N2O-N m-2 h-1 as the transfer coefficient ranged between its 5th and 95th percentile. Assuming a likely value of 100 ?g N2O-N m-2 h-1 for post-grazing N2O fluxes from intensively grazed New Zealand dairy pasture, the system described here would be capable of detecting a mitigation efficacy of 26% for a single (40 min) comparison. We demonstrate that the system has considerably greater sensitivity to treatment effects by measuring cumulative fluxes over extended periods.
McMillan, A. M. S.; Harvey, M. J.; Martin, R. J.; Bromley, A. M.; Evans, M. J.; Mukherjee, S.; Laubach, J.
Methodologies are required to verify agricultural greenhouse gas mitigation at scales relevant to farm management. Micrometeorological techniques provide a viable approach for comparing fluxes between fields receiving mitigation treatments and control fields. However, they have rarely been applied to spatially verifying treatments aimed at mitigating nitrous oxide emission from intensively grazed pastoral systems. We deployed a micrometeorological system to compare N2O flux among several ~ 1.5 ha plots in intensively grazed dairy pasture. The sample collection and measurement system is referred to as the Field-Scale Nitrous Oxide Mitigation Assessment System (FS-NOMAS) and used a tuneable diode laser absorption spectrometer to measure N2O gradients to high precision at four locations along a 300 m transect. The utility of the FS-NOMAS to assess mitigation efficacy depends largely on its ability to resolve very small vertical N2O gradients. The performance of the FS-NOMAS was assessed in this respect in laboratory and field-based studies. The FS-NOMAS could reliably resolve gradients of 0.039 ppb between a height of 0.5 m and 1.0 m. The gradient resolution achieved corresponded to the ability to detect an inter-plot N2O flux difference of 26.4 ?g N2O-N m-2 h-1 under the most commonly encountered conditions of atmospheric mixing (quantified here by a turbulent transfer coefficient), but this ranged from 11 to 59 ?g N2O-N m-2 h-1 as the transfer coefficient ranged between its 5th and 95th percentile. Assuming a likely value of 100 ?g N2O-N m-2 h-1 for post-grazing N2O fluxes from intensively grazed New Zealand dairy pasture, the system described here would be capable of detecting a mitigation efficacy of 26% for a single (40 min) comparison. We demonstrate that the system has considerably greater sensitivity to treatment effects by measuring cumulative fluxes over extended periods.
McMillan, A. M. S.; Harvey, M. J.; Martin, R. J.; Bromley, A. M.; Evans, M. J.; Mukherjee, S.; Laubach, J.
Red Clover (Trifolium pratense) is an important forage legume in grazing pastures. Historically red clover was limited by its comparatively lower stand persistence in hay and grazed systems. Smith (2000) demonstrated increased persistence under hay management achieved through over 30 years of bree...
Examined the impact of the dairy price support program and its resulting higher prices on nutrition intake, especially calcium. A demand system emphasizing dairy products was estimated. Concluded that nutrient intake would increase substantially if the program was terminated. (JOW)
Heien, Dale; Wessells, Cathy Roheim
Rangelands are a type of land cover dominated by grasses, grass-like plants, forbs, and shrubs, where the land is managed as a natural ecosystem for multiple uses including wildlife habitat, biodiversity, recreation, and grazing by livestock. The area cover by rangelands is 48.2% of the land surfac...
Charles Elliot Fleming was one of the first scientists to work on the western range. In 1946 he published a series of questions concerning grazing of the exotic annual cheatgrass (Bromus tectorm), which had invaded millions of acres of the western rangelands. The introduction and subsequent invasi...
Fate and occurrence of fourteen androgens, four estrogens, five glucocorticoids and five progestagens were investigated in three swine farms and three dairy cattle farms with different farming scales and wastes disposal systems in China. Twenty-one, 22, and 12 of total 28 steroids were detected in feces samples with concentrations ranging from below method limit of quantitation (
Liu, Shan; Ying, Guang-Guo; Zhang, Rui-Quan; Zhou, Li-Jun; Lai, Hua-Jie; Chen, Zhi-Feng
We have constructed a grazing incidence x-ray reflection system for liquid-vapor interfaces by use of an imaging plate as an area detector. The reflectivity data were obtained with high resolution even by use of a conventional x-ray tube. The surface reflectivity measurements for pure water, ethanol and 2-butoxyethanol were performed and the values of the surface roughness were obtained as 4.1±0.1, 7.1±0.3 and 6.2±0.2 Å, respectively. For water, slight broadening of reflection peaks was observed. This was caused by the surface curvature due to the large surface tension. By fitting the reflection profiles, the radius of curvature was found to be nearly 100 m for water and ten times larger for ethanol and 2-butoxyethanol.
Yano, Yohko F.; Iijima, Takao
Integrating livestock into a cropping system by allowing ruminant animals to graze cover crops may yield economic and environmental benefits. The effects of grazing on soil physical properties, soil organic matter, nitrogen cycling and agricultural production are presented in this literature review. The review found that grazing cover crops…
The aim of this study was to determine the effectiveness of dairy wastewater treatment in the integrated technology based on the simultaneous use of the activated sludge method (AS) and a hydrophyte system (HS) (AS-HS), in this case, common reed (Phragmites australis) or common cattail (Typha latifolia). Experiments were conducted in an innovative reactor exploited in the fractional-technical scale at the loads of 0.05 mg BOD5/mg.d.m. d (biochemical oxygen demand) and 0.10 mg BOD5/mg.d.m d. The AS--HS enabled improving the removal effectiveness ofbiogenes characterized by concentrations of Ntot., N-NH4 and Ptot. In contrast, the integrated system had no significant reducing effect either on concentrations of organic compounds characterized by BOD5 and chemical oxygen demand parameters or on the structure of AS in the sequencing batch-type reactors. PMID:24701933
Debowski, M; Zieli?ski, M; Krzemieniewski, M; Rokicka, M; Kupczyk, K
Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity and seasonality of livestock grazing alter the structure and diversity of macroarthropod communities compared with traditional grazing practices. Treatments represented a gradient of grazing intensity by cattle and native herbivores: long-term grazing exclosures; moderate summer grazing (the traditional regime); intensive spring grazing; intensive summer grazing; and moderately summer-grazed pastures also inhabited by black-tailed prairie dogs (Cynomys ludovicianus Ord). Beetles and spiders were the most common groups captured, comprising 60% and 21%, respectively, of 4,378 total pitfall captures. Grasshopper counts were generally low, with 3,799 individuals observed and densities <4 m(-2). Two years after treatments were applied, vegetation structure differed among grazing treatments, responding not only to long-term grazing conditions, but also to the short-term, more-intensive grazing manipulations. In response, arthropods were, in general, relatively insensitive to these grazing-induced structural changes. However, species-level analyses of one group (Tenebrionidae) revealed both positive and negative effects of grazing treatments on beetle richness and activity-density. Importantly, these responses to grazing were more pronounced in a year when spring-summer rainfall was low, suggesting that both grazing and precipitation-which together may create the greatest heterogeneity in vegetation structure-are drivers of consumer responses in this system. PMID:24780073
Newbold, T A Scott; Stapp, Paul; Levensailor, Katherine E; Derner, Justin D; Lauenroth, William K
This document provides guidance to State and local governments and to federal agencies on offsite emergency measurement of radionuclides in non-dairy food and potable water to determine dose commitment after an accident involving a light-water nuclear power plant. In the early emergency phase of an accident, monitoring of the ingestion pathway should be primarily directed toward controlling the human ingestion of deposited airborne contamination. Ingestion of edible plants is the non-dairy food pathway of primary concern. The importance of this pathway is dependent on the time of year the nuclide release occurs (e.g. deposition of radionuclides on plants just prior to or during harvest presents the greatest hazard). The greatest immediate concern following a release may be from the radioiodines; however, because of their short half-life, the hazard diminishes rapidly and the longer lived radionuclides of strontium and cesium become important. Protective actions and monitoring requirements are discussed. Several alternatives for field monitoring of foodstuffs and water are presented. However, the recommended procedure for monitoring foodstuffs is field sampling in predetermined areas followed by laboratory analyses. The recommended procedure for monitoring water is collection of samples at water purification plants followed by analyses performed by experienced technical personnel. 32 references, 2 figures, 9 tables.
Salmonson, B.J.; Hoffman, L.G.; Honkus, R.J.; Keller, J.H.
A continuously operated, intermittently fed reactor (fermenter) system with a 2-d solids retention time was proposed for supporting biological nutrient removal from liquid dairy manure. The first objective of this study was to select a material with high fermentation potential to be used as the fermenter feed. Primary sludge, liquid separated dairy manure, and flushed dairy manure were investigated for
Kerem Güngör; Mert B. Müftügil; Jactone Arogo Ogejo; Katharine F. Knowlton; Nancy G. Love
Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve worm control in organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experiment 1, Katahdin lambs grazed bermudagrass (BG; n=14), tall fescue (TF; n=7), or SL (n=19) pastures during early summer months. In Experiment 2, lambs grazed TF (n=15) or SL (n=13) pastures during late summer. Stocking rate of pastures was based on forage availability; additional lambs grazed pastures in Experiment 2, but were not sampled. Lambs were dewormed with 0.5 g COWP if FAMACHA(©) score was >3. In Experiment 1, FEC were reduced within 35 days in SL compared with BG lambs (forage by time, P=0.03). The PCV was more resilient to changes over time in SL compared with other groups of lambs (forage by time, P=0.001). In Experiment 2, FEC were lower (P=0.02) and PCV tended to be higher (P=0.09) in lambs grazing SL compared with TF forage. Incidence of deworming was similar among forage groups in both experiments. Grazing SL reduced FEC in lambs in early and late summer, despite reluctance by lambs to graze. Grazing forage and selective deworming using COWP was effective in lambs. PMID:22226762
Burke, J M; Miller, J E; Mosjidis, J A; Terrill, T H
Loss of nitrate (NO3-) from grazing land is a major cause for surface and ground water contamination. These losses can further increase when other N sources apply to grazing land. The objectives of this work were 1) to study the impact of either dairy effl...
The effect of lameness on the fertility of dairy cattle is well recognized. But, the effect of lameness on the fertility of seasonally breeding cattle in pasture-based systems is less well characterized. This prospective cohort study of 463 cows on 1 farm in the lower North Island of New Zealand was designed to assess the effect of clinical lameness, as identified by farm staff, on the hazard of conception after the planned start-of-mating date. A Cox proportional hazards model with time-varying covariates was used. After controlling for the effect of parity, breed, body weight at calving, and calving-to-planned start of mating interval, the daily hazard of conception for cows identified as lame was 0.78 (95% confidence interval: 0.68-0.86) compared with non-lame cows. Lame cows took 12 d longer to get pregnant compared with their non-lame counterparts. PMID:22032371
Alawneh, J I; Laven, R A; Stevenson, M A
Ingested soil may be a source of minerals to grazing cattle; it may also be a source of radionuclides, heavy metals, and organic toxins. The importance of soil ingestion in the milk pathway depends on the amount of soil ingested, the ratio of the mineral concentration in soil to that in herbage, and the ability of the cattle to solubilize and absorb the soil-derived minerals. The amount of soil ingested by cattle on pasture, in turn, depends upon the stocking level, the quantity of forage available, and the soil ingesting propensity of individual cows. The objective of this note is to summarize some of the information about soil ingestion by dairy cattle and to suggest methods for incorporating soil ingestion into the Hanford Environmental Dose Reconstruction (HEDR) Phase I milk model. 5 refs., 4 tabs.
Repetitive extragenic palindromic PCR fingerprinting of Escherichia coli is one microbial source tracking approach for identifying the host source origin of fecal pollution in aquatic systems. The construction of robust known-source libraries is expensive and requires an informed sampling strategy. In many types of farming systems, waste is stored for several months before being released into the environment. In this study we analyzed, by means of repetitive extragenic palindromic PCR using the enterobacterial repetitive intergenic consensus primers and comparative analysis using the Bionumerics software, collections of E. coli obtained from a dairy farm and from a swine farm, both of which stored their waste as a slurry in holding tanks. In all fecal samples, obtained from either barns or holding tanks, the diversity of the E. coli populations was underrepresented by collections of 500 isolates. In both the dairy and the swine farms, the diversity of the E.?coli community was greater in the manure holding tank than in the barn, when they were sampled on the same date. In both farms, a comparison of stored manure samples collected several months apart suggested that the community composition changed substantially in terms of the detected number, absolute identity, and relative abundance of genotypes. Comparison of E. coli populations obtained from 10 different locations in either holding tank suggested that spatial variability in the E. coli community should be accounted for when sampling. Overall, the diversity in E. coli populations in manure slurry storage facilities is significant and likely is problematic with respect to library construction for microbial source tracking applications. PMID:16204513
Lu, Zexun; Lapen, David; Scott, Andrew; Dang, Angela; Topp, Edward
Livestock grazing on public lands continues to be a source of intense conflict and debate. We analyze this problem using a dynamic game. Low grazing fees let ranchers capture more rent from grazing. This increases the incentive to comply with federally mandated regulations. Optimal grazing contracts therefore include grazing fees that are lower than competitive private rates. The optimal policy
Myles J. Watts; Jay P. Shimshack; Jeffrey T. LaFrance
Dairy farming is a highly productive system producing ample amounts of high-quality milk and meat from fewer cows on less land on fewer, but larger, farms. Despite this consolidation and modernization zoonotic pathogenic bacteria and protozoans remain problems on the modern dairy farm. Although past...
Alternatives to gin trash and manure disposal would benefit both the cotton ginning and dairy industries. Anaerobic digestion produces both methane gas and a class A soil amendment. Gin and dairy wastes were combined in a two-phase anaerobic system to determine the combinations of temperature, rew...
Dairy production systems are well-established sources of greenhouse gas (GHG) emissions. Dairy cows emit methane (CH4) directly, and contribute to carbon dioxide (CO2), nitrous oxide (N2O), and ammonia (NH3) emissions via manure. The substrate on which manure is deposited is likely a control on GHG ...
A new in vitro tool was developed for the identification of veterinary substrates of the main drug transporter in the mammary gland. These drugs have a much higher chance of being concentrated into ovine milk and thus should be detectable in dairy products. Complementarily, a cell model for the identification of compounds that can inhibit the secretion of drugs into ovine milk, and thus reduce milk residues, was also generated. The ATP-binding cassette transporter G2 (ABCG2) is responsible for the concentration of its substrates into milk. The need to predict potential drug residues in ruminant milk has prompted the development of in vitro cell models over-expressing ABCG2 for these species to detect veterinary drugs that interact with this transporter. Using these models, several substrates for bovine and caprine ABCG2 have been found, and differences in activity between species have been reported. However, despite being of great toxicological relevance, no suitable in vitro model to predict substrates of ovine ABCG2 was available. New MDCKII and MEF3.8 cell models over-expressing ovine ABCG2 were generated for the identification of substrates and inhibitors of ovine ABCG2. Five widely used veterinary antibiotics (marbofloxacin, orbifloxacin, sarafloxacin, danofloxacin and difloxacin) were discovered as new substrates of ovine ABCG2. These results were confirmed for the bovine transporter and its Y581S variant using previously generated cell models. In addition, the avermectin doramectin was described as a new inhibitor of ruminant ABCG2. This new rapid assay to identify veterinary drugs that can be concentrated into ovine milk will potentially improve detection and monitoring of veterinary drug residues in ovine milk and dairy products. PMID:24679113
González-Lobato, L; Real, R; Herrero, D; de la Fuente, A; Prieto, J G; Marqués, M M; Alvarez, A I; Merino, G
, Peter Allen and Marcia Lou Mings, and siblings Nancy, Chris and Tim for their support of my career and of this work. TABLE OF CO~S Page INTRODUCTION LITERATURE REVIEW Direct Effects: Soil and Vegetation Interactions Indirect Effects: Grazing...
Mings, Thomas Scott
In pasture-based dairy systems, supplementary feeds are used to increase dry matter intake and milk production. Historically, supplementation involved the provision of the same amount of feed (usually a grain-based concentrate feed) to each cow in the herd during milking (i.e., flat-rate feeding). The increasing availability of computerized feeding and milk monitoring technology in milking parlors, however, has led to increased interest in the potential benefits of feeding individual cows (i.e., individualized or differential feeding) different amounts and types of supplements according to one or more parameters (e.g., breeding value for milk yield, current milk yield, days in milk, body condition score, reproduction status, parity). In this review, we consider the likely benefits of individualized supplementary feeding strategies for pasture-based dairy cows fed supplements in the bail during milking. A unique feature of our review compared with earlier publications is the focus on individualized feeding strategies under practical grazing management. Previous reviews focused primarily on research undertaken in situations where cows were offered ad libitum forage, whereas we consider the likely benefits of individualized supplementary feeding strategies under rotational grazing management, wherein pasture is often restricted to all or part of a herd. The review provides compelling evidence that between-cow differences in response to concentrate supplements support the concept of individualized supplementary feeding. PMID:25582585
Hills, J L; Wales, W J; Dunshea, F R; Garcia, S C; Roche, J R
The Adaptive Grazing Management experiment at the USDA-ARS Central Plains Experimental Range addresses important gaps in our current understanding of grazing management including: 1) lack of management-science partnerships to more fully understand the effect of management decisions, 2) need for mana...
Forage and grazing land systems are increasingly expected to provide services beyond food, feed, and fiber. The concept of multifunctionality in grassland agriculture recognizes ecosystem services beyond these traditional functions to include emerging services such as carbon sequestration, greenhous...
Cooperating.) Distributed in furtherance of the Act of Congress of May 8th and June 30th, 1914. BULLETIN NO. 59. COLLEGE STATION, TEXAS DAIRY BARN PLANS BY J. LYNN THOMAS Dairy Specialist, Extension Service THE WALLACE PRINTING CO., Printers BRYAN, TEXAS 1923... DAIRY BARN PLANS BY J. LYNN THOMAS Dairy Specialist Extension Service Dairy barns generally found in Texas are not such as are actually needed to make the work of producing dairy products as attractive as it should be. Poorly constructed barns cause...
Thomas, J. Lynn
Changes in plant species richness and community composition were investigated across a fence separating heavily grazed communal and lightly grazed commercial farming systems in Namaqualand, South Africa. No significant differences in plant species richness between communal and commercial farming systems were detected either locally within individual plots or overall across all plots. Within-plot, richness of species tolerant of grazing, such
S. W. Todd; M. T. Hoffman
Originally published in 1991 by Timber Press, this out of print book is now available on the Web. Edited by Rodney Heitschmidt and Jerry Stuth, Grazing Management: An Ecological Perspective includes ten chapters, ranging from "Range Animal Nutrition" to "Social and Economic influences on grazing management." Also included are animal and plant species lists.
Grazing behavior and diet selection of grazing ruminants can be influenced by a lot of factors. Firstly, they learn from their dams. Secondly, they learn from peers. Thirdly, they learn by trial and error. Work at our USDA-ARS lab showed that ‘ruminal fill’, or how ‘hungry’ the cow is, can affect gr...
Researchers are still in the early stages of understanding how supplementation affects grazing behavior. Conventional nutrition wisdom, including early research with grazing cattle, has been based almost entirely upon stored feeds fed in confinement. In these situations, most dietary “choices” were ...
Agriculture is the largest source of ammonia (NH3) emission to the atmosphere. Within the agricultural sector, the application of slurry to grasslands as fertilizer is one of the main emission sources. This is a common practice in southern Chile, where most dairy production systems are grazing-based. In Chile, there are few published data of gaseous emissions following slurry application to grassland. The aim of this study was to evaluate NH3 volatilization following dairy slurry application to a permanent grassland on an Andosol soil. Ammonia volatilization was measured in four field experiments (winters of 2009 and 2011 and early and late springs of 2011) using a micrometeorological mass balance method with passive flux samplers following dairy slurry application at a target rate of 100 kg total N ha-1. The accumulated N loss was equivalent to 7, 8, 16 and 21% of the total N applied and 22, 34, 88 and 74% of total ammoniacal nitrogen (TAN) applied for winters 2009 and 2011, and early and late spring 2011, respectively. Ammonia emission rates were high immediately after application and declined rapidly with time, with more than 50% of the total emissions within the first 24 h. Losses were highly influenced by environmental conditions, increasing with temperature and lack of rainfall. Taking into consideration the low N losses via leaching and nitrous oxide emissions reported for the study area, results indicate that NH3 volatilization is the main pathway of N loss in fertilized grasslands of southern Chile. However, dairy slurry application could be an important source of nutrients, if applied at a suitable time, rate and using an appropriate technique, and if soil and climate conditions are taken into consideration. This could improve N use efficiency and reduce N losses to the wider environment.
Martínez-Lagos, J.; Salazar, F.; Alfaro, M.; Misselbrook, T.
We estimate a dairy demand system to evaluate generic dairy advertising in the US, 1990-2005. Previous empirical studies of generic dairy advertising focus only on the market of the advertised good, ignoring potential spill-over and feedback effects. We specify an LA|AIDS model of dairy demand, which allows consistent estimation of cross-price and cross-advertising effects across dairy product markets, and is
Metin Cakir; Joseph V. Balagtas
Thirty-seven Holstein and 26 Brown Swiss dairy cows were used to evaluate the effect of two different cooling systems on physiological and hormonal responses during the summer. A control group of cows had access only to shade (C). A second group was cooled with spray and fans (S/F) and the third group was under an evaporative cooling system called Korral Kool (KK). The maximum temperature humidity index during the trial was from 73 to 85. Rectal temperatures and respiration rates of the C group were higher (P<0.05) than those of the S/F and KK groups in both Holstein and Brown Swiss cows. Triiodothyronine levels in milk were higher (P<0.05) in the KK group than in the S/F and C groups, while cortisol levels were lower (P<0.05) in the C group than in S/F and KK. There was no significant difference in the hormonal response of the two breeds. These results demonstrate that both cooling systems may be used increase the comfort of Holstein and Brown Swiss cows during summer in hot, dry climates. PMID:14624352
Correa-Calderon, Abelardo; Armstrong, Dennis; Ray, Donald; DeNise, Sue; Enns, Mark; Howison, Christine
. Thirty-seven Holstein and 26 Brown Swiss dairy cows were used to evaluate the effect of two different cooling systems on physiological and hormonal responses during the summer. A control group of cows had access only to shade (C). A second group was cooled with spray and fans (S/F) and the third group was under an evaporative cooling system called Korral Kool (KK). The maximum temperature humidity index during the trial was from 73 to 85. Rectal temperatures and respiration rates of the C group were higher (P < 0.05) than those of the S/F and KK groups in both Holstein and Brown Swiss cows. Triiodothyronine levels in milk were higher (P < 0.05) in the KK group than in the S/F and C groups, while cortisol levels were lower (P < 0.05) in the C group than in S/F and KK. There was no significant difference in the hormonal response of the two breeds. These results demonstrate that both cooling systems may be used increase the comfort of Holstein and Brown Swiss cows during summer in hot, dry climates.
Correa-Calderon, Abelardo; Armstrong, Dennis; Ray, Donald; DeNise, Sue; Enns, Mark; Howison, Christine
It is important for dairy operators to review their overall operations regularly and look for inefficiency. Production efficiency in dairies can be improved through changes in culling practices, reproductive efficiency, milk quality and feed rations....
Stokes, Sandra R.
Minimising surface water pollution resulting from farm?dairy effluent application to mole?pipe drained soils. I. An evaluation of the deferred irrigation system for sustainable land treatment in the Manawatu
There is little information available on the magnitude of nutrient losses to surface water from the two?pond and daily irrigation treatment systems for farm?dairy effluent (FDE). A research site has been established on a mole?pipe drained Tokomaru silt loam at Massey University's No. 4 Dairy Farm (475 cows) to investigate some of these issues. The site consists of four plots
D. J. Houlbrooke; D. J. Horne; M. J. Hedley; J. A. Hanly; D. R. Scotter; V. O. Snow
Forty-eight Friesian or Friesian-X factory supply dairy cows were divided into two groups. Group 1 received a supplement of sodiumtripolyphosphate (TPP, 25g P, 25g Na/cow/day), and group 2 a supplement of sodium chloride (25g Na/cow/day). Supplementation began at peak lactation, when the mean serum inorganic phosphorus (Pi) of all cows was 1.13 mmol/l. After four weeks, group 2 changed from NaCl to dicalcium phosphate supplementation (25g P/cow/day). Serum Pi and yields of milk, butterfat and protein were measured before, during and after supplementation. Pasture availability was assessed and P and Ca contents in pasture and the Pi content in milk were also determined. Supplementation raised serum Pi from 1.30 mmol/l (NaCI) to 1.42 mmol/l (TPP, P<0.05) but when dicalcium phosphate replaced NaCl the difference between groups disappeared (P>0.05). P supplementation had no effect on any milk parameter. Pre-grazing pasture mass above estimated grazing height averaged 2260 kg DM and contained >or=0.39 per cent P. It is concluded that a herd mean serum Pi concentration of around 1.2-1.3 mmol/l imposes no limitation to dairy production around the period of peak lactation of grazing dairy cattle. PMID:16031536
Betteridge, K; Haynes, D A; Killen, W J
The objective of this study was to evaluate the nutritional and ecological aspects of feeding systems practiced under semi-arid environments in Jordan. Nine dairy farms representing the different dairy farming systems were selected for this study. Feed samples (n = 58), fecal samples (n = 108), and milk samples (n = 78) were collected from the farms and analysed for chemical composition. Feed samples were also analysed for metabolisable energy (ME) contents and in vitro organic matter digestibility according to Hohenheim-Feed-Test. Furthermore, fecal nitrogen concentration was determined to estimate in vivo organic matter digestibility. ME and nutrient intakes were calculated based on the farmer’s estimate of dry matter intake and the analysed composition of the feed ingredients. ME and nutrient intakes were compared to recommended standard values for adequate supply of ME, utilizable crude protein, rumen undegradable crude protein (RUCP), phosphorus (P), and calcium (Ca). Technology Impact Policy Impact Calculation model complemented with a partial life cycle assessment model was used to estimate greenhouse gas emissions of milk production at farm gate. The model predicts CH4, N2O and CO2 gases emitted either directly or indirectly. Average daily energy corrected milk yield (ECM) was 19 kg and ranged between 11 and 27 kg. The mean of ME intake of all farms was 184 MJ/d with a range between 115 and 225 MJ/d. Intake of RUCP was lower than the standard requirements in six farms ranging between 19 and 137 g/d, was higher (32 and 93 g/d) in two farms, and matched the requirements in one farm. P intake was higher than the requirements in all farms (mean oversupply = 19 g/d) and ranged between 3 and 30 g/d. Ca intake was significantly below the requirements in small scale farms. Milk nitrogen efficiency N-eff (milk N/intake N) varied between 19% and 28% and was mainly driven by the level of milk yield. Total CO2 equivalent (CO2 equ) emission ranged between 0.90 and 1.88 kg CO2/kg ECM milk, where the enteric and manure CH4 contributed to 52% of the total CO2 equ emissions, followed by the indirect emissions of N2O and the direct emissions of CO2 gases which comprises 17% and 15%, respectively, from total CO2 equ emissions. Emissions per kg of milk were significantly driven by the level of milk production (r2 = 0.93) and of eDMI (r2 = 0.88), while the total emissions were not influenced by diet composition. A difference of 16 kg ECM/d in milk yield, 9% in N-eff and of 0.9 kg CO2 equ/kg in ECM milk observed between low and high yielding animals. To improve the nutritional status of the animals, protein requirements have to be met. Furthermore, low price by-products with a low carbon credit should be included in the diets to replace the high proportion of imported concentrate feeds and consequently improve the economic situation of dairy farms and mitigate CO2 equ emissions. PMID:24596499
Alqaisi, Othman; Hemme, Torsten; Hagemann, Martin; Susenbeth, Andreas
The objective of this study was to evaluate the nutritional and ecological aspects of feeding systems practiced under semi-arid environments in Jordan. Nine dairy farms representing the different dairy farming systems were selected for this study. Feed samples (n = 58), fecal samples (n = 108), and milk samples (n = 78) were collected from the farms and analysed for chemical composition. Feed samples were also analysed for metabolisable energy (ME) contents and in vitro organic matter digestibility according to Hohenheim-Feed-Test. Furthermore, fecal nitrogen concentration was determined to estimate in vivo organic matter digestibility. ME and nutrient intakes were calculated based on the farmer's estimate of dry matter intake and the analysed composition of the feed ingredients. ME and nutrient intakes were compared to recommended standard values for adequate supply of ME, utilizable crude protein, rumen undegradable crude protein (RUCP), phosphorus (P), and calcium (Ca). Technology Impact Policy Impact Calculation model complemented with a partial life cycle assessment model was used to estimate greenhouse gas emissions of milk production at farm gate. The model predicts CH4, N2O and CO2 gases emitted either directly or indirectly. Average daily energy corrected milk yield (ECM) was 19 kg and ranged between 11 and 27 kg. The mean of ME intake of all farms was 184 MJ/d with a range between 115 and 225 MJ/d. Intake of RUCP was lower than the standard requirements in six farms ranging between 19 and 137 g/d, was higher (32 and 93 g/d) in two farms, and matched the requirements in one farm. P intake was higher than the requirements in all farms (mean oversupply = 19 g/d) and ranged between 3 and 30 g/d. Ca intake was significantly below the requirements in small scale farms. Milk nitrogen efficiency N-eff (milk N/intake N) varied between 19% and 28% and was mainly driven by the level of milk yield. Total CO2 equivalent (CO2 equ) emission ranged between 0.90 and 1.88 kg CO2/kg ECM milk, where the enteric and manure CH4 contributed to 52% of the total CO2 equ emissions, followed by the indirect emissions of N2O and the direct emissions of CO2 gases which comprises 17% and 15%, respectively, from total CO2 equ emissions. Emissions per kg of milk were significantly driven by the level of milk production (r (2) = 0.93) and of eDMI (r (2) = 0.88), while the total emissions were not influenced by diet composition. A difference of 16 kg ECM/d in milk yield, 9% in N-eff and of 0.9 kg CO2 equ/kg in ECM milk observed between low and high yielding animals. To improve the nutritional status of the animals, protein requirements have to be met. Furthermore, low price by-products with a low carbon credit should be included in the diets to replace the high proportion of imported concentrate feeds and consequently improve the economic situation of dairy farms and mitigate CO2 equ emissions. PMID:24596499
Alqaisi, Othman; Hemme, Torsten; Hagemann, Martin; Susenbeth, Andreas
Many dairy production systems have a critical need for available sites to land apply dairy slurry after spring planting and during the summer months. One potential option is to apply these nutrients on perennial grass sods; however, this approach is viable only if voluntary intake by livestock is no...
A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.
Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.
Efficient pasture-based milk production systems require a compact calving pattern aligned to the onset of the grazing season, a 365-day calving interval and low culling rates for infertility. Achievement of these targets requires high herd reproductive performance. While high genetic merit Holstein cows produce more milk in grass-based systems their fertility is compromised. Management of the modern high genetic merit Holstein dairy cow presents a major challenge in pasture-based systems of production. It appears that the extent of early embryo loss is greater (up to 20% points greater) in the modern high-producing dairy cow and that a much higher proportion of the embryos die before day 7 following insemination in contrast to heifers and lower yielding cows. About 7-8% of pregnancies are lost between days 30 and 90 of gestation with no evidence that loss rate is related to cow genetic merit, parity or level of production. Systemic concentrations of progesterone during both the cycle preceding and following insemination affect embryo survival rate with evidence that too low or indeed too high a concentration of progesterone been negatively associated with embryo survival rate. Peripheral concentrations of both progesterone and oestradiol are lowered by increased plane of feed intake due to increased metabolic clearance rate of the steroids, which is related to liver blood flow. It appears that high producing dairy cows have an increased risk of embryo death as a result of lowered peripheral concentrations of progesterone as a consequence of increased hepatic metabolism of progesterone. Uterine expression of mRNA for progesterone receptor, oestradiol receptor and retinol binding protein mRNA appears to be sensitive to changes in peripheral concentrations of progesterone during the first week after AI. It would appear that energy balance and dry matter intake during the 4 weeks, immediately after calving are critically important in determining conception rate when cows are inseminated at 70-100 days post-calving. Concentrate supplementation of cows at pasture during the breeding period has minimal affects on conception rates though sudden reduction in dietary intake should be avoided. For pasture-based systems of milk production more balanced breeding strategies, with greater emphasis on fertility and feed intake must be developed. PMID:16963203
Diskin, M G; Murphy, J J; Sreenan, J M
The objectives of this study were to determine the influence of housing on lameness-related linear and composite traits, and to estimate heritabilities of the traits and correlations among them. Data comprised 156,770 national type evaluation records of pedigreed first-lactation Holstein-Friesian cows that calved from 2000 through 2006 and were classified in different housing systems--cubicles, straw yards, slatted or loafing yards, and on pasture. Locomotion score (LOCO), rear leg, side view (RLS), foot angle (FA), bone quality (BO-NEQ), legs and feet (L&F), and mammary composite (MAMM) were the traits measured. Data were analyzed by REML, using an animal model. In general, cows in grazing systems had better locomotion, straighter RLS, steeper FA, flat and more refined bones, better L&F, and better mammary systems compared with cows housed in other systems. Estimates of heritability ranged from 0.11 for LOCO to 0.31 for MAMM. Bone quality had the highest heritability (0.23) of the traits associated with L&F. Genetic associations between BO-NEQ and LOCO, L&F, and MAMM were moderate to high (0.30 to 0.50), but estimates between BONEQ and RLS and FA were not significantly different from zero. Locomotion score had a very high genetic (0.98) and phenotypic (0.78) correlation with L&F, indicating that both traits are genetically the same. On the basis of the genetic parameters, including BONEQ in a selection index as a predictor of longevity is promising, but further information on its association with longevity is required. PMID:18096954
Onyiro, O M; Brotherstone, S
Parameters indicative of vitamin E status were monitored for over 4 yr in dairy cows to determine if feeding cows only stored feeds could cause deficiency of vitamin E. Low-E cows were fed stored feeds all year whereas the pastured cows grazed during summer. A third group pastured only while dry also was moni- tored the 4th yr. There were
D. J. Schingoethe; J. G. Parsons; F. C. Ludens; W. L. Tucker; H. J. Shave
Western ranchers are currently paying fair market value for grazing on public lands through the grazing fee, higher non-fee giazing costs, and investments to buy range improve- ments and the grazing permit. Past grazing fee policies have contributed to the significant value of grazing permits and current ranchers have paid this cost. Recognition or lack of recognition of permit cost
L. Allen Torell; E. Tom Bartlett; Frederick W. Obermiller
Background Genomic evaluations are rapidly replacing traditional evaluation systems used for dairy cattle selection. Economies of scale in genomics promote cooperation across country borders. Genomic information can be transferred across countries using simple conversion equations, by modifying mult...
The aim of this study was to evaluate the productive and biological efficiency of steers and heifers from dairy genetics in a feedlot system in terms of meat production. Twenty-four steers and 24 heifers at 10 monthes of age, (3/4) Zebu × (1/4) Holstein were utilized. They were distributed over four feedlot times, 30, 60, 90, and 120 days with four replications for each sex, and were slaughtered at the end of each period. The productive and biological analyses were performed through comparative slaughter to determine the body composition. Heifers presented with greater intakes (P < 0.05) of dry matter in grams per kg of body weight. Steers presented with a greater (P < 0.05) final empty body weight, carcass gain, cold carcass weight, and meat proportion in the carcass; however, heifers presented with a greater subcutaneous fat thickness (P < 0.05) and, consequently, a greater (P < 0.05) fat proportion in the carcass. We conclude that steers are more efficient in their productive performance than heifers in a feedlot. For the finishing carcass fat cover, heifers need 90 days in the feedlot. The net energy requirements for maintenance are 67?kcal/EBW0.75/d, and the net requirements of energy (NEg) and protein (NPg) for gain can be estimated by the following equations: NEg(Mcal/d) = 0.067 × EBW0.75 × EBG1.095 and NPg = 162 × EBG ? 5.62 × RE for the two sexes. PMID:25574483
Menezes, Gustavo Chamon de Castro; Valadares Filho, Sebastião de Campos; Ruas, José Reinaldo Mendes; Detmann, Edenio; Menezes, Arismar de Castro; Zanett, Diego; Mariz, Lays Débora Silva; Rennó, Luciana Navajas; da Silva Junior, Jarbas Miguel
The growth performance of embryo-transferred Japanese Black calves that were born from, and suckled by, Japanese Shorthorn cows in a cow-calf grazing system (BS-group, n = 5) was compared to that of Japanese Black calves from Japanese Black cows in a cowshed (BB-group, n = 5). The daily weight gain from birth to 1 month was higher in the BS-group than in the BB-group (p<0.01), and the same trend (p<0.05) was observed at 2 and 3 months of age. This resulted in body weight that was significantly higher for the BS-group between 1 and 3 months of age than what was observed for the BB-group (p<0.05). Heart girth was significantly greater in the BS-group than in the BB-group throughout the experimental period (p<0.01), and chest depth and withers height in the BS-group were significantly greater from 2 to 4 months of age (p<0.05) and at 4 months of age only (p<0.05). No difference in body length (p>0.05) was observed between the groups. These results suggest that the maternal effect of Japanese Shorthorn cows was positive for embryo-transferred Japanese Black calf growth during the early suckling stage. As Japanese Black calves are traded at a high price on the Japanese market, we conclude that this proposed production system is likely to improve the profitability of herd management in upland Japan. PMID:25049870
Yamaguchi, Manabu; Ikeda, Kentaro; Takenouchi, Naoki; Higashiyama, Masakazu; Watanabe, Akira
The aim of this study was to evaluate daily weight gain (DWG), total dry matter (DM) intake, rumen degradability of forage, and urinary excretion of mimosine metabolites by hair sheep in a silvopastoral system with high densities of Leucaena leucocephala. A completely randomized design was carried out with two treatments: treatment 1 (T1) silvopastoral system with leucaena at a density of 35,000 plants/ha and treatment 2 (T2), leucaena at a density of 55,000 plants/ha. Leucaena was associated with tropical grasses Panicum maximum and Cynodon nlemfluensis. Twenty-four male Pelibuey lambs of 23.2 ± 3.4 kg live weight (LW) were used (12 lambs per treatment). Results showed differences (P < 0.05) in DWG of T1 (106.41 ± 11.66 g(-1) sheep(-1)) with respect to that of T2 (81.33 ± 11.81 g(-1) sheep). Voluntary intake was higher in lambs from T1 (83.81 ± 04.07 g DM/kg LW(0.75)) with respect to that from T2 (71.67 ± 8.12 g DM/kg LW(0.75)). There was a difference in color of urine between sheep of T1 and T2, the latter giving positive results for the presence of metabolites derived from mimosine (3-4 dihydroxypyridine and 2-3 dihydroxy pyridone). Rumen degradability of DM of L. leucocephala was higher (P < 0.05) compared to that of P. maximum and C. nlemfluensis (72.94 ± 0.40 vs. 67.06?±?1.50 and 63.25 ± 1.51 %, respectively). It is concluded that grazing at high densities of L. leucocephala affects daily weight gain of hair sheep, possibly due to ingestion of high amounts of mimosine which may exert an adverse effect on voluntary intake. PMID:22528536
Barros-Rodríguez, Marcos; Solorio-Sánchez, Javier; Ku-Vera, Juan; Ayala-Burgos, Armín; Sandoval-Castro, Carlos; Solís-Pérez, Georgina
Agriculture contributes 20 to 25 % of the total anthropogenic greenhouse gas (GHG) emissions globally. These agricultural emissions are primarily in the form of methane (CH4) and nitrous oxide (N2O) with these GHG accounting for roughly 40 and 80 % of the total anthropogenic emissions of CH4 and N2O, respectively. Due to varied management and the complexities of agricultural ecosystems, it is difficult to estimate these CH4 and N2O emissions. The IPCC emission factors can be used to yield rough estimates of CH4 and N2O emissions but they are often based on limited data. Accurate modeling validated by measurements is needed in order to identify potential mitigation areas, reduce GHG emissions from agriculture, and improve sustainability of farming practices. The biogeochemical model Manure DNDC was validated using measurements from two dairy farms in New Hampshire, USA in order to quantify GHG emissions under different management systems. One organic and one conventional dairy farm operated by the University of New Hampshire's Agriculture Experiment Station were utilized as the study sites for validation of Manure DNDC. Compilation of management records started in 2011 to provide model inputs. Model results were then compared to field collected samples of soil carbon and nitrogen, above-ground biomass, and GHG fluxes. Fluxes were measured in crop, animal, housing, and waste management sites on the farms in order to examine the entire farm ecosystem and test the validity of the model. Fluxes were measured by static flux chambers, with enteric fermentation measurements being conducted by the SF6 tracer test as well as a new method called Greenfeeder. Our preliminary GHG flux analysis suggests higher emissions than predicted by IPCC emission factors and equations. Results suggest that emissions from manure management is a key concern at the conventional dairy farm while bedded housing at the organic dairy produced large quantities of GHG.
Dorich, C.; Contosta, A.; Li, C.; Brito, A.; Varner, R. K.
Prices for milk and dairy products have become increasingly unstable as the Government support safety net has been lowered. Dairy cooperatives’ traditional pricing system is delineated and their role in the new market environment is discussed. Some of the risks involved in using emerging hedging mechanisms such as futures, options, and forward contracting for managing price risks are assessed. The traditional pricing system in regard to managing price risks is evaluated. Guidelines for developing a cooperative’s hedging strategy are suggested.
United States; Price Risks Abstract; K. Charles Ling; Carolyn Betts Liebr
Bacteria levels are the number one cause of water quality impairment in Texas. Several recent Total Maximum Daily Loads (TMDLs) in Texas, such as those implemented in the Peach Creek and Leon River watersheds, have identified grazing cattle as a...
Wagner, K.; Redmon, L.; Gentry, T.; Harmel, D.; Jones, C. A.
), a brood parasite. Cowbirds can reduce productivity of their hosts, causing some host species to decline in abundance. Thus, grazing indirectly influences productivity of some songbirds. The black-capped vireo (Vireo atricapilla) is an endangered...
116 Forage resources in tsamdrog and broadleaf forests are declining in quantity and quality due to increasing numbers of grazing cattle. In order to take the pressure off the forests, the tsamdrog in broadleaf forests must be improved... off to establish plantations or regeneration. In the quest to improve forest stands, lack of important tree regeneration and change of species composition in broadleaf forests is attributed to cattle grazing (FAO 1985; Millar 1986, Janze, 1990...
farmers who are finding it difficult to compete with lowland farmers in the production of agriculture crops. Dukpa et al (1997) estimated that silvopastoral systems combining the fast growing blue pine with dairy production could generate cash... advantage of new regulations introduced. Herders/farmers are not motivated to optimize production of tsamdrog. Tsamdro which cannot be utilized due to logistic problems (distance) are not available for other herders/farmers. Communal resources...
The objectives of this study were to characterize the variation in curd firmness model parameters obtained from coagulating bovine milk samples, and to investigate the effects of the dairy system, season, individual farm, and factors related to individual cows (days in milk and parity). Individual milk samples (n=1,264) were collected during the evening milking of 85 farms representing different environments and farming systems in the northeastern Italian Alps. The dairy herds were classified into 4 farming system categories: traditional system with tied animals (29 herds), modern dairy systems with traditional feeding based on hay and compound feed (30 herds), modern dairy system with total mixed ration (TMR) that included silage as a large proportion of the diet (9 herds), and modern dairy system with silage-free TMR (17 herds). Milk samples were analyzed for milk composition and coagulation properties, and parameters were modeled using curd firmness measures (CFt) collected every 15 s from a lacto-dynamographic analysis of 90min. When compared with traditional milk coagulation properties (MCP), the curd firming measures showed greater variability and yielded a more accurate description of the milk coagulation process: the model converged for 93.1% of the milk samples, allowing estimation of 4 CFt parameters and 2 derived traits [maximum CF (CFmax) and time from rennet addition to CFmax (tmax)] for each sample. The milk samples whose CFt equations did not converge showed longer rennet coagulation times obtained from the model (RCTeq) and higher somatic cell score, and came from less-productive cows. Among the sources of variation tested for the CFt parameters, dairy herd system yielded the greatest differences for the contrast between the traditional farm and the 3 modern farms, with the latter showing earlier coagulation and greater instant syneresis rate constant (kSR). The use of TMR yielded a greater tmax because of a higher instant curd-firming rate constant (kCF). Season of sampling was found to be very important, yielding higher values during winter for all traits except kCF and kSR. All CFt traits were affected by individual cow factors. For parity, milk produced by first-lactation cows showed higher kCF and kSR, but delays in achieving CFmax. With respect to stage of lactation, RCTeq and potential asymptotic CF increased during the middle of lactation and stabilized thereafter, whereas the 2 instant rate constants presented the opposite pattern, with the lowest (kCF) and highest (kSR) values occurring in mid lactation. The new challenge offered by prolonging the test interval and individual modeling of milk technological properties allowed us to study the effects of parameters related to the environment and to individual cows. This novel strategy may be useful for investigating the genetic variability of these new coagulation traits. PMID:25682135
Bittante, G; Cipolat-Gotet, C; Malchiodi, F; Sturaro, E; Tagliapietra, F; Schiavon, S; Cecchinato, A
The performance of wether lambs on crownvetch (Coronilla varia L.) pasture was determined for three seasons under five grazing procedures. These included continuous grazing and rotational grazing with a 7?day period?of stay and periods?of?absence of 7, 21, 35 or 49 days. Performance was the same with all five systems. Supplementary measurements involving oesophageal?fistula samples and quadrat harvests indicated that the
D. L. Barnes; C. P. Dempsey
heavily grazed pastures were low (4. 1 cm/h) (Dortignac and Love, 1961; Smith 1967). Menzel et al. (1978) observed at the South Central Agricultural Research Station in Oklahoma that watersheds having a moderately-stocked rotation grazing system...ASSESSMENT OF INTENSIVE SILVICULTURAL PRACTICES AND LIVESTOCK GRAZING ON WATERSHED PARAMETERS, KISATCHIE NATIONAL FOREST, LOUISIANA A Thesis by THOMAS KENNETH HUNTER JR. Submitted to the Graduate College of Texas A&M University in partial...
Hunter, Thomas Kenneth
As semi-natural grassland has a high level of biological diversity, understanding the effects of grazing and its variation over time is important in order to identify sustainable grazing practices. We measured temporal variation in Orthoptera abundance and spatial vegetation structure during seasonal grazing in an extensive sheep-farming system. We studied five grazed pasture areas (pre-grazing and post-grazing) and two adjacent ungrazed grasslands. We recorded the total abundance of Orthoptera and described the vegetation structure of 175 replicate plots (25 per pasture/grassland) during six field sampling sessions. We demonstrated that the impact of grazing on Orthoptera abundance is species-specific and greatly varies over the grazing season. The decrease of phytovolume is significant after 4-7 weeks of sheep grazing. Total Orthoptera abundance was higher in pre-grazed plots than in ungrazed plots, and higher in ungrazed plots than in post-grazed plots. These differences were particularly high during the peak of adult abundance. No difference in species richness was observed between grazing intensities. Total Orthoptera abundance positively correlated to phytovolume only when grazing pressure was high. However, the relationship between abundance and phytovolume differed between species. Extensive grazing by sheep tends to homogenize spatial vegetation structure and to temporarily reduce total Orthoptera abundance at pasture scale. However, rotational grazing allows spatial and temporal heterogeneity in vegetation structure to be maintained at farm scale, heterogeneity that is beneficial for Orthoptera. In contrast, absence of grazing has a negative impact on Orthoptera abundance as it favours the accumulation of litter, which is detrimental for a high proportion of xerothermophilic Orthoptera associated with bare ground and short vegetation.
Fonderflick, Jocelyn; Besnard, Aurélien; Beuret, Aurore; Dalmais, Mathieux; Schatz, Bertrand
Around the world, dairy farmers are transforming dairy waste to compost for land application. In southeastern Australia, farmers are using composted dairy waste to increase production and reduce costs. In addition, the farmers are considering the benefits of compost for increasing sequestration of soil carbon, and on-farm nutrient retention. The "Carbon Farming Initative" in Australia is exploring the option to allow farmers to trade Carbon Credits for carbon stored in the soil. Compost also retains vital nutrients, such as N, on farm rather than importing N in the form of mineral fertilisers. Composting also reduces greenhouse gas emissions, such as CH4, compared to when stored in effluent ponds. This project will investigate if dairy compost applied to pasture improves carbon sequestration, nutrient retention and pasture production. In this project dairy compost, made from dairy effluent, feedpad waste, spoilt sillage and wood mulch, was applied onto a 1Ha field and companion plots at a rate of 0, 3, 6 and 12 t/ha. The field plot is open to grazing and normal farm management practices. The companion plots are being subjected to simulated grazing (mowing). The trials, currently underway will run for 18 months. Along with preliminary soil carbon results, this work will also include preliminary data for total and plant available nutrients, and farm biomass production. The outcomes of this research, and benefits it finds for "Carbon Farming" and nutrient retention has practical, policy and economic applications for world wide markets.
Drake, Jess; Cavagnaro, Tim; Patti, Tony; Wilkinson, Kevin; McDonald, Declan; Johnston, Priscilla; Wilson, Katrina; Rose, Mick; Jackson, Roy
Dairy farms control an important share of the agricultural area of Northern Italy. Zero grazing, large maize-cropped areas, high stocking densities, and high milk production make them intensive and prone to impact the environment. Currently, few published studies have proposed indicator sets able to describe the entire dairy farm system and their internal components. This work had four aims: i) to propose a list of agro-environmental indicators to assess dairy farms; ii) to understand which indicators classify farms best; iii) to evaluate the dairy farms based on the proposed indicator list; iv) to link farmer decisions to the consequent environmental pressures. Forty agro-environmental indicators selected for this study are described. Northern Italy dairy systems were analysed considering both farmer decision indicators (farm management) and the resulting pressure indicators that demonstrate environmental stress on the entire farming system, and its components: cropping system, livestock system, and milk production. The correlations among single indicators identified redundant indicators. Principal Components Analysis distinguished which indicators provided meaningful information about each pressure indicator group. Analysis of the communalities and the correlations among indicators identified those that best represented farm variability: Farm Gate N Balance, Greenhouse Gas Emission, and Net Energy of the farm system; Net Energy and Gross P Balance of the cropping system component; Energy Use Efficiency and Purchased Feed N Input of the livestock system component; N Eco-Efficiency of the milk production component. Farm evaluation, based on the complete list of selected indicators demonstrated organic farming resulted in uniformly high values, while farms with low milk-producing herds resulted in uniformly low values. Yet on other farms, the environmental quality varied greatly when different groups of pressure indicators were considered, which highlighted the importance of expanding environmental analysis to effects within the farm. Statistical analysis demonstrated positive correlations between all farmer decision and pressure group indicators. Consumption of mineral fertiliser and pesticide negatively influenced the cropping system. Furthermore, stocking rate was found to correlate positively with the milk production component and negatively with the farm system. This study provides baseline references for ex ante policy evaluation, and monitoring tools for analysis both in itinere and ex post environment policy implementation. PMID:24747935
Gaudino, Stefano; Goia, Irene; Grignani, Carlo; Monaco, Stefano; Sacco, Dario
This impact evaluation of a refrigeration control system (RCS) recently installed at Vitamilk Dairy, Inc. (Vitamilk) was conducted for the Bonneville Power Administration (Bonneville) as part of an evaluation of its Energy $avings Plan (E$P) Program. The RCS installation at Vitamilk uses microcomputer- based controls to automate refrigeration equipment previously controlled manually. This impact evaluation assessed how much electricity is being saved at Vitamilk as a result of the E$P and to determine how much the savings cost Bonneville and the region. On a unit savings basis, this project will save 9.7 kWh/tonne (8-8 kWh/ton) of milk and ice cream produced, based on the product mix for June 1992 through May 1993, representing a 28% reduction in energy consumption. The project was installed in 1992 for a total cost of $129,330, and Vitamilk received payment of $62,974 from Bonneville in 1993 for the acquisition of energy savings. The real levelized cost of these energy savings to Bonneville is 8.5 mills/kWh (in 1993 dollars) over the project`s assumed 15-year life, and the real levelized cost to the region is 17.9 mills/kWh (in 1993 dollars), not including transmission and distribution effects. Based on the expected project installation costs and energy savings benefits, the RCS would not have been implemented by Vitamilk without the E$P acquisition payment. The expected acquisition payment reduced the estimated payback period from 7.0 to 2.8 years. Although Vitamilk would generally require an energy conservation project to have a payback period of two years or less, the slightly longer payback period was accepted in this case.
Brown, D.R.; Dixon, D.R.; Spanner, G.E.
Effects on animal cleanliness and foot health of a new rubber-slat system for tied dairy cows, with the ability to drain faeces and urine, were studied in a 2-year controlled quasi-randomised trial in a Swedish university herd. Swedish Red and White cows were kept tied in 42 traditional long-stalls with rubber mats. In total, 82 cows were observed. In 21 stalls, the rearmost 0.74m of the solid stall floor was replaced with nine rubber-coated 53mm wide slats, divided by 29mm slots. The cleanliness was assessed subjectively weekly (year 1) or bi-weekly (year 2) by observations of the hind part of the body. Claw measurements and foot health in hind feet were assessed in connection with hoof trimmings at the beginning, middle and end of the housing period. The foot-health recordings were blinded to flooring. For the analysis of both cleanliness (1781 records, 73 cows) and foot health (240 records, 79 cows), logistic regression was applied, using marginal models and cow observations as repeated measures within each year. The risk of getting dirty on the rubber-slatted floor was significantly lower (odds ratio 0.12 for hind feet when short stall dividers were used, 0.39 for hind legs and 0.38 for thighs and udder), comparing with the solid stall floor. The prevalence of foot diseases in hind feet at trimming was significantly lower on the rubber slats (odds ratio 0.23 for dermatitis, 0.09 for heel horn erosion, and 0.34 for sole ulcer or sole or white line haemorrhage). PMID:11566380
Hultgren, J; Bergsten, C
Earlier research showed that conjugated linoleic acid (CLA) content in milk fat is highest when cows' diets are supplemented with a blend of fish oil (FO) and linoleic acid-rich oils. The objective of this study was to compare the effect of FO and sunflower oil (SFO) supplementation on milk cis-9, trans-11 CLA when dairy cows managed on pasture or in
A. A. AbuGhazaleh; D. O. Felton; S. A. Ibrahim
Silvopasture is receiving increasing attention as a robust management system for production of forage for livestock grazing on the diverse landscapes of the Appalachian region. Little knowledge about soil water response to slope aspect and grazing pressure in silvopasture systems of the Region is a...
Content? Summary Six factors influence greatly the profits from Grade "4' milk production, as shown by this study of dairy farm operation; in East and Central Texas, with additional data from experimen. tal dairy herds at Substation No. 2... at Tyler, Texas. ......................... 1 Summary ~tluction ... Intrt Purr -r\\ Procedure >ose and _ 1- 1. High average production is extremely important to pra I fitable dairying. At the average price paid for milk tetting 4 percent butterfat...
Magee, A. C.; Stone, B. H.; Leighton, R. E.; Carpenter, S. E.
The attitudes and expectations of producers toward the use of a microcomputer-based herd management information system were assessed. The study was conducted over a two-year period, beginning in January 1986, and was operated as a bureau service. The implementation and use of the program are described elsewhere. Pre- and posttrial questionnaires were administered to assess producer attitudes. We found that the monthly analysis reports were used in the management of the dairy farms and were found to be a useful management tool. The majority of producers indicated a willingness to pay, on average, $6.86/cow/year for such a service. PMID:17423946
Lissemore, Kerry D.; Leslie, Ken E.; Martin, S. Wayne; Menzies, Paula I.; Meek, Alan H.
A new editing system for records used to compute USDA-DHIA genetic evaluations was developed to allow im- mediate and more complete checking of data. The system uses direct (immediate on-line) access to pedigree and some lac- tation information to evaluate new data received. Birth dates are checked against parent birth dates and dam calving dates. For most conflicts, existing data
H. D. Norman; L. G. Waite; G. R. Wiggans; L. M. Walton
The DFG research group 536 MAGIM (Matter fluxes in grasslands of Inner Mongolia as influenced by stocking rate) investigates the influence of grazing intensity on matter and water cycles in grazed steppe ecosystems of Inner Mongolia. This Sino-German co-operation applies an interdisciplinary approach to investigate major ecosystem functions and how they are affected by grazing and overgrazing. Within the research group an indicator system is developed to systemize the feedback of ecosystem parameters to the influence of grazing and to analyse, which parameter or parameter group reacts most sensitively. Parameters were measured at up to five different grazing intensities (from ungrazed to heavy grazed) and are related to four thematic indicator groups (plant productivity, atmosphere, pedosphere, hydrosphere). The parameters were scaled to allow assessing the influence of grazing intensity between different sets of parameters. For this the average value of a parameter at the lowest grazing intensity (ungrazed) was set 100%, so that the values at the other intensities could be scaled scaled adequately. Then the difference between highest and lowest grazing intensity was determined. According to this difference the influence of grazing was characterized as weak (< 20% difference), medium (20-40%), strong (40-60%) and very strong (> 60%). Impact of grazing on the parameters will be marked as weak (w), medium (m), strong (s) and very strong (vs) in the text. The group plant productivity includes the vegetation parameters aboveground biomass and belowground biomass. Belowground biomass (s) was significantly different between grazing treatments with the highest value at the ungrazed site (399.00 g m-2 a-1) and the lowest at the heavy grazed site (208.00 g m-2 a-1). Aboveground biomass (m) ranged between 91.33-131.67 g m-2 a-1 and differed significantly between the ungrazed and the heavy grazed site, again with higher values at the ungrazed site (Gao et al. 2008). The group atmosphere consists of micrometeorological parameters, dust flux and deposition as measure of erosive processes and trace gas fluxes. Available energy and soil temperature were always significantly different between two simultaneously measured grazing intensities. Available energy was higher at the ungrazed site in all years measured (mean difference of about 19 W m-2). Soil temperature was lower at the ungrazed site (Ketzer et al. 2008). Dust deposition is important for the C and N balance in semi-arid grasslands and was investigated during the dust storm period from March to May. The largest matter deposition of C (vs) and N (vs) was measured at the ungrazed site with 328.7 (mg Corg m-2 d-1) and 30.30 (mg Nt m-2 d-1) on average. Heavy grazing resulted in average organic carbon and nitrogen deposition of 106.67 (mg Corg m-2 d-1) and 9.8 (mg N m-2 d-1) in average (Hoffmann et al. 2008). Wind driven soil deposition and erosion were influenced heavily by grazing. The critical vegetation cover is about 20-30%, at which net soil losses occur. No significant differences in N trace gas fluxes were found between plots. Mean values of N2O fluxes (s) varied between 0.39 and 1.60 ?g N2O-N m-2 h-1 (Holst et al. 2007). During all measuring periods, significantly lower mean soil CH4 uptake at moderate grazing (28 mg C m-2 h-1) as compared to ungrazed (56 ?g C m-2 h-1) was found (Liu et al. 2007). The pedosphere indicator group includes soil chemical, soil physical and microbiological parameters. Organic carbon (s) and total N (s) concentrations decreased significantly with increasing grazing intensity. No effect of grazing on pH (w) or soil C/N ratio (w) was detected. Bulk density (m) significantly increased with increasing grazing intensity, from 0.94 g cm-3 at the ungrazed site to 1.28 g cm-3 at the heavily grazed site (Steffens et al. 2008). Also shear strength (m) increased with increasing grazing intensity (Zhao et al. 2007). Gross rates of N mineralization (vs) and nitrification (vs) determined at in situ soil moisture and soil temperature conditions were i
Blank, B.; Breuer, L.; Butterbach-Bahl, K.; Frede, H.-G.
Multiple demands are placed on farming systems today. Society, national legislation and market forces seek what could be seen as conflicting outcomes from our agricultural systems, e.g. food quality, affordable prices, a healthy environmental, consideration of animal welfare, biodiversity etc., Many of these demands, or desirable outcomes, are interrelated, so reaching one goal may often compromise another and, importantly, pose
A. Del Prado; T. Misselbrook; D. Chadwick; A. Hopkins; R. J. Dewhurst; P. Davison; A. Butler; J. J. Schroder; D. Scholefield
Grazing management has a significant impact on pasture growth. We determined how timing of grazing influences grass productivity, yield distribution, and persistence. Meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], orchardgrass (Dactylis glomerata L.), quackgrass [Elymus repens (L.) Gould...
Goat mammary epithelial cells (GMECs) are a useful model to understand the physiological function of mammary glands and to assess the efficiency of mammary-specific vectors. The aim of this study was to develop an effective and convenient way to evaluate the secretory capacity of GMECs in primary culture. In this study, we developed a reporter system using fluorescent proteins driven by the CSN2 (Capra hircus beta-casein) gene promoter to detect the secretory capacity of GMECs. Additionally, we evaluated the efficiency of the reporter system by determining the expression of cytoskeletal proteins and beta-casein protein. The results suggest that this reporter system provides an easy, convenient and effective method to detect the function of milk synthesis in GMECs. Primary cultures of GMECs were homogeneous and retained the function of milk synthesis, prompting their usefulness as a model for further studies. PMID:25681763
Wang, Lizhong; Ren, Caifang; You, Jihao; Fan, Yixuan; Wan, Yongjie; Zhang, Yanli; Wang, Feng; Huang, Mingrui
The first year of a 2 yr grazing study was conducted to evaluate use of Chaparral™ to suppress reproductive growth in tall fescue grazed with low and moderate grazing intensities. Chaparral applications (0 and 2.0 oz/acre) and grazing intensities were arranged as RCBD with three replications. Variab...
Hydrologic restoration of ditched and drained wetlands within the 12000 km2 Lake Okeechobee basin (LOB), FL is expected to promote carbon (C) accretion and phosphorus (P) retention. The majority of P loading to Lake Okeechobee is attributed to historical pasture fertilization and continued high density cattle activity which perpetuate elevated P transport to the lake from dairies and cow/calf operations. Isolated wetlands which dominate the LOB landscape have been historically ditched to increase pasture area for grazing. Current best management practices intended to reduce P transport to the lake include the option of fencing wetlands in cattle pastures to prevent cattle access. The objective of this study was to develop a predictive model of the dynamics of wetland biomass, soil accretion, C and P. The coupled effects of grazing intensity, highly transient water level, and seasonality were incorporated. The model was conditioned based on approximately three years of monitoring data from four isolated wetlands in the LOB. Drought-induced declining water table resulted in decreased wetland plant biomass in both grazed and ungrazed simulations but reduction was more severe in the grazed simulations. High intensity grazing during flooded conditions resulted in declines in wetland plant biomass due to disconnection between leaves and the air column. Standing biomass and C and P storage in vegetation increased with the exclusion of grazing in these wetlands. Although vegetation nutrient storage is short term, biomass turnover supports accretion of soil and associated C and P. Predicted implications for C and P sequestration at the watershed scale and reduction of P load to the lake are directly related to the wetland area that can be excluded from grazing.
Mitchell, J. D.; Jawitz, J. W.
Searching for livestock production systems with a high energy utilization is of interest because of resource use and pollution aspects and because energy use is an indicator of the intensification of production processes. Due to interactions between crop and livestock enterprises and between levels of different input factors and their effects on yields, it is proposed to analyze agricultural energy
Karen Refsgaard; Niels Halberg; Erik Steen Kristensen
With the aim of assessing the secondary benefits of using electronic identification (e-ID) in sheep farms, we compared the use of manual (M), semiautomatic (SA), and automatic (AU) data-collection systems for performance recording (i.e., milk, lambing, and weight) in 3 experiments. Ewes were identified with visual ear tags and electronic rumen boluses. The M system consisted of visual ear tags, on-paper data recording, and manual data uploading to a computer; the use of a personal digital assistant (PDA) for data recording and data uploading was also done in M. The SA system used a handheld reader (HHR) for e-ID, data recording, and uploading. Both PDA and HHR used Bluetooth for uploading. The AU system was only used for body weight recording and consisted of e-ID, data recording in an electronic scale, and data uploading. In experiment 1, M and SA milk-recording systems were compared in a flock of 48 dairy ewes. Ewes were milked once- (×1, n=24) or twice- (×2, n=24) daily in a 2 × 12 milking parlor and processed in groups of 24. Milk yield (1.21 ± 0.04 L/d, on average) was 36% lower in ×1 than ×2 ewes and milk recording time correlated positively with milk yield (R(2)=0.71). Data transfer was markedly faster for PDA and HHR than for M. As a result, overall milk recording time was faster in SA (×1=12.1 ± 0.6 min/24 ewes; ×2=22.1 ± 0.9 min/24 ewes) than M (×1=14.9 ± 0.6 min/24 ewes; ×2=27.9 ± 1.0 min/24 ewes). No differences between PDA and HHR were detected. Time savings, with regard to M, were greater for ×2 than for ×1 (5.6 ± 0.2 vs. 2.8 ± 0.1 min per 24 ewes, respectively), but similar for PDA and HHR. Data transfer errors averaged 3.6% in M, whereas no errors were found in either SA system. In experiment 2, 73 dairy and 80 meat ewes were monitored at lambing using M and SA. Overall time for lambing recording was greater in M than SA in dairy (1.67 ± 0.06 vs. 0.87 ± 0.04 min/ewe) and meat (1.30 ± 0.03 vs. 0.73 ± 0.03 min/ewe) ewes. Recording errors were greater in dairy (9.6%) than in meat (1.9%) ewes. Data uploading errors only occurred in M (4.9%). In experiment 3, 120 dairy and 120 meat ewes were weighed using M and AU systems. In both flocks, mean BW recording and data uploading times, as well as overall BW recording time (0.63 ± 0.02 and 0.25 ± 0.01 min/ewe, respectively) were greater in M than in AU, and uploading errors only occurred in M (8.8%). In conclusion, HHR and PDA systems were time-effective for performance recording, both saving time and improving data accuracy. Working load and time for ewe identification were faster in HHR but it did not affect the performance recording time. The PDA was the fastest device for data download. Further research will evaluate the costs of implementing e-ID for performance recording and other uses in sheep farms. PMID:25282408
Ait-Saidi, A; Caja, G; Salama, A A K; Carné, S
Ninety-four cows were randomly allocated to 1 of 5 stocking rates (2.2, 2.7, 3.1, 3.7, and 4.3 cows/ha) in a completely randomized design for 3 years. Herds were seasonal calving, with only minor differences in grazing management to optimize the profitability of each stocking rate (SR). Pasture production and quality data, milk and milk component data, and reproduction data were collected, averaged for SR treatment, and linear and quadratic contrasts on SR were evaluated. In addition, the Wilmink exponential model (y(t) = a + b x e((-0.05t) )+ c x t) was fitted to milk yield within lactation, and the parameters were averaged by SR treatment and analyzed as above. The median variation explained by the function for individual lactations was 84%. The amount of pasture grown tended to increase, and the quality of the pasture on offer increased linearly with increasing SR, reducing some of the negative impact of SR on the availability of pasture per cow. Milk production per cow declined linearly with increasing SR, although there was a tendency for most production variables to decline quadratically, with the negative effect of SR declining with increasing SR. The effect on milk production per cow was primarily because of a lower peak milk yield and a greater post-peak decline (less persistent milk profile), although a decline in lactation length with increasing SR was responsible for 24% of the effect of SR on milk yield. Milk production per hectare increased linearly with increasing SR, and there was only a small difference (approximately 3%/cow per ha) in the efficiency of converting feed dry matter into milk energy. Stocking rate did not affect reproductive success. The data are consistent with the need for a more robust measure of SR than cows per hectare because farms will differ in the genetic merit of their cows and in the potential to produce pasture. We introduce the concept of a comparative SR, whereby the carrying capacity of the farm is defined by the BW of the cows, the potential of the land to produce pasture, and the amount of supplement purchased (kg of BW/t of feed dry matter). The adoption of such a measure would facilitate the extrapolation and transfer of research findings among systems. PMID:18420647
Macdonald, K A; Penno, J W; Lancaster, J A S; Roche, J R
This monograph, designed to help secondary students recognize symptoms of major dairy cattle diseases, stresses the need for preventative management practices and cooperation between the dairy farmer and the veterinarian. The first of three parts, The Healthy Animal, is divided into five units: body parts, vital signs, excretions, behavior, and…
Wolanyk, Alison M.; Bishop, Natalie
Congress and the Clinton Administration have sought to revise federal policies on public land grazing. Legislation pending in Congress differs significantly from reforms sought by the Administration, although the Administration softened its original proposal and dropped the proposed fee increases. California has many acres of federal land available for grazing, but the amount and impact of that grazing are modest
KENNETH W. UMBACH
A recent survey 1 of dairymen in Minnesota, Michigan, Wisconsin and New York studied the antibiotic use strategies used on nearly 100 conventional and 30 organic dairies. They found that 71% of the dairies kept antibiotic treatment records for lactating dairy cows. Slightly over half of the dairies kept records of treatment of dry-cows and only a third kept records
John H. Kirk; Extension Veterinarian
Greenhouse gas (GHG) emissions from dairy farms are a major concern. Our objectives were to assess the effect of mitigation strategies on GHG emissions and net return to management on 3 distinct farm production systems of Wisconsin. A survey was conducted on 27 conventional farms, 30 grazing farms, and 69 organic farms. The data collected were used to characterize 3 feeding systems scaled to the average farm (85 cows and 127ha). The Integrated Farm System Model was used to simulate the economic and environmental impacts of altering feeding and manure management in those 3 farms. Results showed that incorporation of grazing practices for lactating cows in the conventional farm led to a 27.6% decrease in total GHG emissions [-0.16kg of CO2 equivalents (CO2eq)/kg of energy corrected milk (ECM)] and a 29.3% increase in net return to management (+$7,005/yr) when milk production was assumed constant. For the grazing and organic farms, decreasing the forage-to-concentrate ratio in the diet decreased GHG emissions when milk production was increased by 5 or 10%. The 5% increase in milk production was not sufficient to maintain the net return; however, the 10% increase in milk production increased net return in the organic farm but not on the grazing farm. A 13.7% decrease in GHG emissions (-0.08kg of CO2eq/kg of ECM) was observed on the conventional farm when incorporating manure the day of application and adding a 12-mo covered storage unit. However, those same changes led to a 6.1% (+0.04kg of CO2eq/kg of ECM) and a 6.9% (+0.06kg of CO2eq/kg of ECM) increase in GHG emissions in the grazing and the organic farms, respectively. For the 3 farms, manure management changes led to a decrease in net return to management. Simulation results suggested that the same feeding and manure management mitigation strategies led to different outcomes depending on the farm system, and furthermore, effective mitigation strategies were used to reduce GHG emissions while maintaining profitability within each farm. PMID:24996278
Dutreuil, M; Wattiaux, M; Hardie, C A; Cabrera, V E
Automatic milking systems (AMS) rely upon voluntary cow traffic (the voluntary movement of cattle around a farm) for milk harvesting and feed consumption. Previous research on conventional milking systems has shown differences between dairy cow breeds for intake and milk production, however, the ability to manipulate voluntary cow traffic and milking frequency on AMS farms through breed selection is unknown. This study investigated the effect of breed (Holstein Friesian versus Illawarra) on voluntary cow traffic as determined by gate passes at the Camden AMS research farm dairy facility. Daily data on days in milk, milk yield, gate passes and milking frequency for 158 Holstein Friesian cows and 24 Illawarra cows were collated by month for the 2007 and 2008 years. Illawarra cows had 9% more gate passes/day than Holstein cows over the duration of the study; however, the milking frequency and milk yield of both breeds were similar. Gate passes were greatest for both breeds in early lactation and in the winter (June to August) and summer (December to February) seasons. These findings highlight an opportunity to translate increased voluntary cow movement associated with breed selection into increased milking frequencies, milk production and overall pasture-based AMS performance. PMID:25049992
Clark, C. E. F.; Kwinten, N. B. P.; van Gastel, D. A. J. M.; Kerrisk, K. L.; Lyons, N. A.; Garcia, S. C.
The rural areas were identified for milk production; the urban centers were collected for the location of milk processing plants and product manufacturing factories. Out of the total water consumed by human being, more than 50 % of it is consumed for industrial activity and only small proportion is used for drinking purpose. The water after use emerging out of industry is better termed as waste water or industrial effluent (Sukumar De, 2002). DAIRY TECHNOLOGY-As the rapid industrialization taking place all over the country, the number of dairies and allied industries are sharply rising. I.Product and process involved in dairy-Many dairies restrict themselves bottling pasteurized milk and making ghee from scoured milk. In few dairies
To evaluate cattle grazing effects on the potential for sediment and nutrient loading of surface waters, forage cover, sward height, and mass and manure cover were measured in pastures with different grazing management systems. Six 12.1-ha cool-season grass pastures were assigned one of three treat...
of deterioration of riparian systems on public lands (Carothers 1977. Cope 1979). Studies of riparian sites have198 Structural Resilience Of A Willow Riparian Community To Changes In Grazing Practices Fritz L to studies that indicate fish habitats respond quickly to changes in grazing practices, terrestrial habitats
Rangeland grazing management strategies affect soil properties and the distribution and cycling of nutrients within the plant-soil system, but these effects are not well understood. We studied the effects of 12 years of five livestock grazing management strategies on (C) and nitrogen (N) contents of...
Grass-based dairy farming has long been the mainstay of the dairy industry in the temperate maritime regions of the world such as the United Kingdom, Ireland, and New Zealand. In contrast, U.S. dairy farms are predominantly characterized by confinement feeding systems. However due to increased pro...
A study was carried out to investigate the feasibility of integrating an advanced gasifier into the operation of a dairy farm for converting biomass wastes into fuel gas that can be used for power production. The disposal\\/utilization of excess animal wastes is a serious problem facing the dairy industry. Implementation of a gasification system on the dairy farm may provide
Lincoln Young; Carlson C. P. Pian
Effects of right versus left side activities of the reproductive organs on sperm transport after deep cornual insemination were evaluated in 1686 Friesian cows in their first lactational period. Only single ovulating animals were used. At insemination, semen was deposited deep into the uterine horn ipsilateral or contralateral to the preovulatory follicle. Pregnancy rates were used as measurement of the success of sperm transport. The reproductive history of each cow included that of the side of the previous gestation. A higher activity of the right versus left side was registered. Following calving and after uterine involution, activities of the right versus left side reproductive organs remained constant independently of the side of previous pregnancy, and did not affect transuterine sperm transport. The data indicate that after uterine involution sperm transport is not affected by bilateral asymmetry of the reproductive system in cattle. PMID:16728079
Waste milk has been fed to calves for many years, but concerns with bacterial contamination as well as possible transmission of diseases have discouraged widespread use of this feed. Pasteurization of waste milk is one option to reduce management risk while utilizing a valuable, low-cost, liquid feed source for calves. However, many farms currently pasteurizing waste milk lack a system to adequately monitor the efficiency of the process. A study was carried out to evaluate 6 on-farm pasteurization systems, including high-temperature, short-time pasteurizers and low-temperature, batch pasteurizers. Milk samples were taken pre- and postpasteurization as well as from the calf buckets and immediately frozen for later bacterial culture. Samples were collected twice daily for 15 d. Milk samples were examined for standard plate count (SPC), coagulase-negative staphylococci count, environmental streptococci count, coliform count, gram-negative noncoliform count, Streptococcus agalactiae count, and Staphylococcus aureus count. Before pasteurization, 68% of the samples had SPC <20,000 cfu/mL, and 39% of samples contained <100 cfu/mL of coliform bacteria. After pasteurization, 96% of samples had SPC <20,000 cfu/mL, and 92% had coliform counts <100 cfu/mL. Bacteria counts were significantly reduced by pasteurization, and pasteurized milk contained acceptable numbers of bacteria in >90% of samples. These results indicate that pasteurization can be very effective in lowering bacterial contamination of milk. However, bacteria numbers significantly increased after pasteurization and, in some cases, bacteria counts in milk fed to calves were similar to prepasteurization levels. Milk handling after pasteurization was identified as an important issue on the farms studied. PMID:20965367
Elizondo-Salazar, J A; Jones, C M; Heinrichs, A J
Background Prophylactic measures are key components of dairy herd mastitis control programs, but some are only relevant in specific housing systems. To assess the association between management practices and mastitis incidence, data collected in 2011 by a survey among 979 randomly selected Swiss dairy farms, and information from the regular test day recordings from 680 of these farms was analyzed. Results The median incidence of farmer-reported clinical mastitis (ICM) was 11.6 (mean 14.7) cases per 100 cows per year. The median annual proportion of milk samples with a composite somatic cell count (PSCC) above 200,000 cells/ml was 16.1 (mean 17.3) %. A multivariable negative binomial regression model was fitted for each of the mastitis indicators for farms with tie-stall and free-stall housing systems separately to study the effect of other (than housing system) management practices on the ICM and PSCC events (above 200,000 cells/ml). The results differed substantially by housing system and outcome. In tie-stall systems, clinical mastitis incidence was mainly affected by region (mountainous production zone; incidence rate ratio (IRR) = 0.73), the dairy herd replacement system (1.27) and farmers age (0.81). The proportion of high SCC was mainly associated with dry cow udder controls (IRR = 0.67), clean bedding material at calving (IRR = 1.72), using total merit values to select bulls (IRR = 1.57) and body condition scoring (IRR = 0.74). In free-stall systems, the IRR for clinical mastitis was mainly associated with stall climate/temperature (IRR = 1.65), comfort mats as resting surface (IRR = 0.75) and when no feed analysis was carried out (IRR = 1.18). The proportion of high SSC was only associated with hand and arm cleaning after calving (IRR = 0.81) and beef producing value to select bulls (IRR = 0.66). Conclusions There were substantial differences in identified risk factors in the four models. Some of the factors were in agreement with the reported literature while others were not. This highlights the multifactorial nature of the disease and the differences in the risks for both mastitis manifestations. Attempting to understand these multifactorial associations for mastitis within larger management groups continues to play an important role in mastitis control programs. PMID:24107254
Weight and pressure distribution on the claw were studied in Swedish Holsteins housed in different flooring systems. A total of 127 cows housed in different sections of the experimental barn were used. Each section had different flooring in the walking and standing areas. There were rubber mats or abrasive mastic asphalt flooring on the alleys or a low-abrasive slatted concrete floor. Some sections had feed-stalls equipped with rubber mats; other sections did not. The vertical ground reaction force, contact area, and average contact pressure were determined on the left hind foot using the I-Scan system and analyzed with the F-scan system. These determinations were made in each of the following 3 zones of the claw: bulb, wall, and sole. Most of the weight on claws exposed to concrete floors was carried by the bulb (37.4 +/- 3.5 and 18.3 +/- 2.9% of weight exerted on the foot in the lateral and medial claw, respectively) and the wall zone (20.0 +/- 2.6 and 13.4 +/- 2.4% on lateral and medial claw, respectively). The weight and pressure distribution in cows kept on sections with rubber covered alleys but passing daily over the asphalt floor on their way to the milking parlor did not differ in any zones, except for lateral bulbs, compared with those exposed to slatted concrete alone. Still, the weight bearing of the sole zone in cows kept on rubber mats without access to asphalt was less than that of cows kept on concrete slatted floors (5.1 +/- 0.7 vs. 12.7 +/- 1.1% and 1.1 +/- 0.5 vs. 8.7 +/- 0.7% in lateral and medial claws, respectively). In cows kept on asphalt flooring without feed-stalls, most weight was exerted to the sole zone (36.2 +/- 2.9 and 22.2 +/- 1.8% in lateral and medial claws, respectively). Feed-stalls in combination with asphalt flooring yielded a decreased total contact area (30.1 +/- 1.2 cm(2)) compared with asphalt floors without feed-stalls (35.7 +/- 1.2 cm(2)). The largest total contact area was obtained on the asphalt floor without feed-stalls, resulting in a lower contact pressure (39.8 +/- 2.3 N/cm(2)) than in claws exposed to concrete (66.0 +/- 2.7 N/ cm(2)) or rubber mats (56.7 +/- 1.7 N/cm(2)). In conclusion, housing with abrasive floors resulted in claws with increased contact area at the sole surface and therefore, decreased contact pressure, but reduced the weight-bearing role of the strongest part of the claw capsule, the claw wall. PMID:18420618
Telezhenko, E; Bergsten, C; Magnusson, M; Ventorp, M; Nilsson, C
One-hundred eight lactations of Murciano-Granadina goats from different years were used to compare two kid rearing systems. Goats were separated into two groups: suckling and milking. Dams in the suckling group were milked once daily until kids were weaned (wk 0 to 7) and then were milked twice daily. Dams in the milking group were separated from their kids at 48 h after birth; then, kids were raised artificially, and goats were milked twice daily. Total milk yield was estimated according to the oxytocin method during suckling. Stage of lactation, parity, prolificacy, and year effects on milk yield and composition were also studied. As expected, during the first 7 wk of lactation, marketable milk was higher for dams that were milked than for dams that were suckled. Neither milk yield nor milk composition throughout the entire lactation was affected by group or prolificacy with the exception of the percentage of milk CP. The lactation curve peaked at wk 4 or 5 and declined slowly afterward. First parity goats had the lowest milk yield but the highest fat and protein percentages. Third parity goats had the highest milk yield. The separation of kids from their dams after birth did not affect total lactation performance because of the minimal importance of the neuroendocrine milk ejection reflex in goats compared with that of other ruminants. PMID:9436106
Peris, S; Caja, G; Such, X; Casals, R; Ferret, A; Torre, C
Grazing management is probably one of the most extensive land uses, but its effects on plant communities have in many cases been revealed to be contradictory. Some authors have related these contradictions to the stochastic character of grazing systems. Because of that, it is necessary to implement specific analyses of grazing effects on each community, especially in natural protected areas, in order to provide the best information to managers. We studied the effects of grazing on the species composition of the main vegetation types where it takes place (grasslands, shrublands and pine forests) on the island of La Palma, Canary Islands. We used the point-quadrat intersect method to study the species composition of grazed and ungrazed areas, which also were characterized by their altitude, distance to farms, distance to settlements, year of sampling, herbaceous aboveground biomass and soil organic matter. The variables organic matter, productivity and species richness were not significantly affected by grazing. The species composition of the analyzed plant communities was affected more by variables such as altitude or distance to farms than by extensive grazing that has been traditionally carried out on the island of La Palma involving certain practices such as continuous monitoring of animals by goat keepers, medium stocking rates adjusted to the availability of natural pastures, supplementation during the dry season using local forage shrubs or mown pastures and rotating animals within grazing areas Although some studies have shown a negative effect of grazing on endangered plant species, these results cannot be freely extrapolated to the traditional grazing systems that exert a low pressure on plant communities (as has been found in this study). We consider extensive grazing as a viable way of ensuring sustainable management of the studied ecosystems.
Arévalo, J. R.; de Nascimento, L.; Fernández-Lugo, S.; Mata, J.; Bermejo, L.
A dynamic, stochastic, mechanistic simulation model of a dairy business was developed to evaluate the cost and benefit streams coinciding with technology investments. The model was constructed to embody the biological and economical complexities of a dairy farm system within a partial budgeting fram...
agricultural CH4 emissions, with liquid systems commonly used by the dairy industry contributing up to 74% of this. Anaerobic digestion (AD) is able to reduce emissions from the dairy industry by capturing CH4 emissions released from slurry and forming a biogas...
Grazing of cover crops in grain cropping systems can increase economic return and diversify agricultural production systems, but the environmental consequences of this intensified management have not been well documented, especially under different tillage systems. We conducted a multiple-year investigation of how cover crop management (grazed and ungrazed) and tillage system [conventional (CT; initial moldboard plowing and thereafter disk tillage)
Alan J. Franzluebbers; John A. Stuedemann
Dairy cow mortality is an increasingly severe problem for the US dairy industry. The objective of this study was to examine a variety of herd management practices and herd characteristics to identify factors associated with increased cow mortality in US dairy herds. The National Animal Health Monitoring System's Dairy 2002 study surveyed dairy operations in 21 major dairy states. The complete data set included results from 953 dairy farms with a minimum of 30 dairy cows per farm. Associations between dairy cow mortality and 119 a priori-selected management practices or characteristics of 953 operations were evaluated. Eighty of the 119 risk factors explored in a univariate analysis met initial inclusion criteria for further evaluation of association with dairy cow mortality. A multivariable analysis was conducted to explore more complex relationships. The final multivariable model included 7 representative variables: herd levels of respiratory disease, lameness, and antibiotic use for treating sick cows, the percentage of culled cows less than 50 d in milk, the average calving interval, the use of a total mixed ration, and the region of the country. Increased odds of a greater level of mortality on farms was associated with greater percentages of lameness, respiratory disease, and sick cows treated with antibiotics, demonstrating the influence of physical derangements and disease on dairy cow mortality. Increased odds of a greater level of mortality was also associated with feeding a total mixed ration, culling fewer cows in early lactation, and herds located in western, midwestern, and southeastern regions relative to the northeastern United States, pointing to the importance of management decisions and operation characteristics on mortality outcomes. Further, an important interplay between facets of health and management on dairy cow mortality was suggested through the inclusion of the calving interval, with a longer calving interval leading to increased odds of a greater level of mortality on farms. Analysis of a variety of herd characteristics and practices with nationally representative data suggests that several health problems in tandem with aspects of operational construct and management are associated with increasing mortality. PMID:18349234
McConnel, C S; Lombard, J E; Wagner, B A; Garry, F B
African grasses introduced for grazing have expanded in geographic extent in mesic tropical systems of Hawaii and other regions of the world. Grassland expansion leads to increases in fire frequency, speeding woodland and forest destruction at greater geographic scales than occurs with grazing alone. At Pu'uwa'awa'a Ranch, Hawaii, restoration of the native woodland habitat has become a critical objective following the introduction and dominance of the African grass species Pennisetum clandestinum and P. setaceum. Grazing and grass-fueled fires have destroyed over 60% of the original forest. To stabilize these communities, managers must balance the combined effects of grazing and fire. Grazing reduces the recruitment success of native tropical trees, but grazing also reduces fire risk by moderating grass fuel conditions and restricting the extent and density of the most flammable grass species. Our study focuses on two questions: (1) What grazing intensity is necessary to change the fire conditions of a region given in situ soil and precipitation conditions? (2) Have long-term grazing conditions altered soil carbon and nitrogen stocks? We used high resolution imaging spectrometer data to measure photosynthetic and non-photosynthetic vegetation cover, analysis of soil carbon and nitrogen stocks, and measurements of plant community composition along gradients in grazing intensity. P. setaceum, the more flammable alien grass, was dominant where grazing intensity was low and at lower elevations where precipitation is low. The less flammable grass, P. clandestinum, occurred in regions of high grazing intensity and higher precipitation. Grazing influenced the dominance of P. setaceum and P. clandestinum only where precipitation and soil characteristics were suitable for both grasses to occur. At suitable sites, grazing reduced fire conditions through a species sift towards P. clandestinum. Soil carbon and nitrogen stocks decreased with grazing intensity, which was correlated with the fractional cover of P. setaceum. Soil carbon also increased with precipitation. These results show how grazing impacts fire conditions and soil chemistry through changes in species composition, and not through removal of carbon inputs (direct removal of biomass).
Elmore, A. J.; Asner, G. P.
When incorporating targeted grazing into farming systems, livestock producers and farm operators need assurance that the benefits from their activities are worth their investments. Cropping systems were once integrated with livestock production: livestock gained forage value from crop aftermath, c...
One of the main goals of the BYU Thin Films group is to find optical constants for materials in the Extreme Ultraviolet. This is accomplished by taking reflection and transmission measurements. The addition of a Grazing Incidence Monochromator to our current system allows us to take reflectance measurements at wavelengths currently unavailable on the Normal Incidence Monochromator (Monarch).
Barton, Sarah; Turley, R. Steven
Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experi...
Two different types of pasture (cultivated and rangeland) and 2 different hay qualities (high and low quality) were examined for their effects on goat milk composition and rennet coagulation properties. Furthermore, the effect of dietary treatments in both the early and late grazing season was studied. As lactation stage is known to influence milk composition, the goats in the early and late grazing season were in the same lactation stage at the start of the experiment. The milk composition was influenced both by dietary treatment and season. Milk from goats on pasture was superior to those on hay by containing a higher content of protein and casein, and the goats on cultivated pasture had the highest milk yield. Casein composition was significantly influenced by forage treatment. Goats grazing on cultivated pasture had higher contents of ?s1-casein and also of ?-casein compared with the other treatments, whereas goats grazing on rangeland had the highest content of ?-casein. Factors such as milk yield, casein micelle size, ?s2-casein, and calcium content were reduced in late compared with early season. More favorable rennet coagulation properties were achieved in milk from the early grazing season, with shorter firming time and higher curd firmness compared with milk from the late grazing season, but the firming time and curd firmness were not prominently influenced by forage treatment. The content of ?s2-casein and calcium in the milk affected the firming time and the curd firmness positively. The influence of season and forage treatment on especially milk yield, casein content, and rennet coagulation properties is of economic importance for both the dairy industry and goat milk farmers. PMID:24704223
Inglingstad, R A; Steinshamn, H; Dagnachew, B S; Valenti, B; Criscione, A; Rukke, E O; Devold, T G; Skeie, S B; Vegarud, G E
The size of modern dairy plant operations has led to extreme specialization in product manufacturing, milk processing, microbiological analysis, chemical and mathematical computations. Morrisville Agricultural and Technical College, New York, has modernized its curricula to meet these changes. (HD)
Sliva, William R.
The somatotropic axis [including growth hormone (GH), GH receptor, and insulin-like growth factor (IGF)-I] is uncoupled in high-producing cows in early lactation so that the liver fails to respond to GH and produces less IGF-I. This uncoupling was implicated in the process of nutrient partitioning, enabling high milk production. Different genetic selection goals may affect functional components of the somatotropic axis. Thus, the somatotropic axis was examined in diverse genetic strains of dairy cows [North American Holstein 1990 (NA90), New Zealand Holstein-Friesian 1990 (NZ90), and New Zealand Holstein-Friesian 1970 (NZ70)] that were managed similarly within a pasture-based system but were offered feed allowances commensurate with their genetic ability to produce milk. The NA90 cows produced more milk (26.2 +/- 0.3, 24.1 +/- 0.3, and 20.1 +/- 0.4 kg/d, for NA90, NZ90, and NZ70, respectively), but had lower milk fat percentages (4.28 +/- 0.03, 4.69 +/- 0.03, and 4.58 +/- 0.04 kg/d for NA90, NZ90, and NZ70, respectively) compared with both NZ strains. Milk protein percentages (3.38 +/- 0.02, 3.52 +/- 0.02, and 3.29 +/- 0.03 kg/d for NA90, NZ90, and NZ70, respectively) were greater for NZ90 cows. During early lactation (wk 2 to 6), the total net energy produced in milk was greater in NA90 compared with NZ90 or NZ70 cows, but total net energy in milk after wk 6 was equivalent for NA90 and NZ90 cows. The greater milk production in early lactation in NA90 cows was associated with lower body condition scores (BCS; 1 to 10 scale; 4.0 +/- 0.1) elevated blood GH concentrations (1.6 +/- 0.1 ng/mL), and low blood IGF-I concentrations (14.8 +/- 1.1 ng/mL), indicating an uncoupled somatotropic axis. In comparison, the NZ70 cows retained a coupled somatotropic axis during early lactation, maintaining greater BCS (4.6 +/- 0.1), lower blood GH (0.7 +/- 0.1 ng/mL), and greater blood IGF-I (21.9 +/- 1.2 ng/mL). The degree of uncoupling in NZ90 cows was intermediate between the other 2 strains. Additional feed allowance failed to change blood IGF-I concentrations in NA90 cows but increased IGF-I concentrations in NZ90 cows (20.9 +/- 1.4 and 13.2 +/- 1.4 ng/mL for the high and low feed allowance, respectively). Furthermore, additional feed allowance in NZ90 cows lessened BCS loss in early lactation, but did not affect BCS loss in NA90 cows. Functional components of the somatotropic axis differed for the respective strains and were consistent with strain differences in milk production, BCS, and feed allowance. PMID:19164663
Lucy, M C; Verkerk, G A; Whyte, B E; Macdonald, K A; Burton, L; Cursons, R T; Roche, J R; Holmes, C W
Recently, it has been proposed on theoretical grounds that carrion odor from flowers may not only attract pollinators, but also repel mammalian herbivores. Two grazing experiments involving 16 to 26 cattle heads per year, one for eight years (1982–1989) and the other for seven (1994–2000), in a region with no large carnivores that could influence cattle behavior, show that cattle avoid areas where dead cattle have recently been dumped. They grazed much less in these unfenced plots that were used to dump dead cattle each year. In the first experiment, with an area of ca. 20,000 m2 per head, the average grass biomass at the end of the season was 124.6 gr/m2 for the regular grazing area, whereas it was 236.5 gr/m2 for the carcass dumping area. In the second experiment, with a higher stocking level, with ca. 9,000 m2 per head, the average grass biomass at the end of the season was 61.7 gr/m2 for the regular grazing area, and 153.7 gr/m2 for the carcass dumping area. These significant differences existed throughout the 15 y of the experiments. We propose that these results are clear evidence of necrophobia in cattle, a character that might defend them from both pathogenic microbes and predators. This in turn demonstrates that carrion odor, primarily used by plants to attract pollinators, can simultaneously defend plants from herbivory by mammals as proposed. PMID:25210579
Lev-Yadun, Simcha; Gutman, Mario
Lameness is one of the most serious health and welfare problems for dairy cows. This study compared hoof health, limb health and locomotion of dairy cows in three over-winter management systems. Treatments were: (1) an indoor free-stall system (FS), (2) outdoors on an uncovered woodchip pad (UP) and (3) outdoors on a covered woodchip pad (CP). Animals were assigned to treatments at drying off, remained on treatment until parturition, then turned out to pasture. Sole lesions were scored on assignment to treatment, at calving, and 6 weeks and 12 weeks post partum. Locomotion and skin lesions were scored on assignment to treatment, and every 2 weeks until parturition. Post-partum locomotion was scored weekly for 13 weeks. More FS cows were affected by limb lesions than CP cows, and these animals had the worst locomotion scores post calving. There was an effect of inspection, and interactive effect of inspection and treatment on sole lesion scores. UP cows had the highest sole lesion scores 12 weeks post partum probably due to softening of the hooves arising from exposure to moisture while on the woodchip pad. However, post partum, UP cows had better locomotion scores, and CP cows tended to have better scores than cows in FS. Both of these treatments were less likely to have a high tracking-up score than cows in FS. It is possible that cows in this treatment were able to exercise more, owing to the secure underfoot surface and lack of barriers, and this promoted limb flexibility. Although woodchip pads provided benefits for limb health and locomotion, the wood chip surface in both outdoor systems did not offer protective benefits to the hooves relative to housing on concrete. However, the provision of shelter on the pad somewhat overcame the problem of high sole lesion scores in the post-partum period. PMID:18922200
O'Driscoll, Keelin Km; Hanlon, Alison; French, Padraig; Boyle, Laura A
An animal-health monitoring system in the Gyeongnam area was started in 1997 to develop statistically valid data for use in estimating disease frequencies in dairy cattle, and the associated costs. The objectives of this study were to: (1) describe what was done to implement and maintain the system in Gyeongnam; (2) present selected disease frequencies; (3) discuss the epidemiological consideration
S. Kim Jong; S. Kim Gong; H. Kim Chung; S. Hah Dae
Forage production during periods of summer drought can be increased by including additional species in the pasture mixture, especially if those species have desirable attributes such as improved water use efficiency or deep root systems. Conversion of plowed fields to pasture also has the potential ...
The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,<200 cows) and medium-sized conventional herds (MC, ?200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic producers stated they had not treated them. In conclusion, gastrointestinal parasite egg counts were low overall at the time of the survey, and most surveyed producers did not perceive gastrointestinal parasites to be a problem for their animals' health. Independent of the herd type, fly control was mostly targeted at the lactating herd and preweaned calves. PMID:25726119
Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J
We investigated the influence of long-term (56 years) grazing on organic and inorganic carbon (C) and nitrogen (N) contents of the plant–soil system (to 90 cm depth) in shortgrass steppe of northeastern Colorado. Grazing treatments included continuous season-long (May–October) grazing by yearling heifers at heavy (60–75% utilization) and light (20–35% utilization) stocking rates, and nongrazed exclosures. The heavy stocking rate
Jean D. Reeder; Gerald E. Schuman; Jack A. Morgan; Daniel R. LeCain
Diet selection by sheep grazing dryland lucerne with a high proportion of weeds was assessed in two consecutive years (2005\\/2006). The study was performed on 2.66 ha of pasture divided in two homogeneous paddocks subjected to a stocking rate of either 10 or 20 sheep\\/paddock, and grazed for 17 days. Before and after each grazing trial, an inventory was conducted
E. Pérez; A. de Vega; I. Delgado; Y. Pueyo
We have developed X-ray grazing incidence optics with a single mirror. Although t can be used to demonstrate and test on the ground to verify the feasibility of X-ray detection system, it is unable to meet the requirements of X-ray pulsar navigation due to small effective area and large mass. There is an urgent need to develop multilayer nested grazing incidence optics, which consists of multilayer mirrors to form a coaxial and confocal system to maximize the use of space and increase the effective area. In this paper, aiming at the future demand of X-ray pulsar navigation, optimization and analysis of nested X-ray grazing incidence optics was carried out, the recurrence relations between the layers of mirrors were derived, reasonable initial structural parameters and stray light reduction method was given, and theoretical effective collection area was calculated. The initial structure and stray light eliminating structure are designed. The optical-mechanical-thermal numerical model was established using optical analysis software and finite element software for stray light analysis, focusing performance analysis, tolerance analysis, and mechanical analysis, providing evidence and guidance for the processing and alignment of nested X-ray grazing incidence optics.
Zuo, Fuchang; Deng, Loulou; Mei, Zhiwu; Li, Liansheng; Lv, Zhengxin
Mediterranean rangelands are unique marginal ecosystems, which are characterized by a highly heterogeneous structure and are often interwoven with other ecosystems. Traditionally, rangelands provided resources for livestock grazing in transhumantic rotation schemes. In recent times, there has been a trend towards semi-intensive grazing systems, which is partly connected to the European system of agricultural and infrastructural subsidies, and which effectuates
A. Röder; Th. Udelhoven; J. Hill; G. del Barrio; G. Tsiourlis
The ever-growing volume of data routinely collected and stored in everyday life presents researchers with a number of opportunities to gain insight and make predictions. This study aimed to demonstrate the usefulness in a specific clinical context of a simulation-based technique called probabilistic sensitivity analysis (PSA) in interpreting the results of a discrete time survival model based on a large dataset of routinely collected dairy herd management data. Data from 12,515 dairy cows (from 39 herds) were used to construct a multilevel discrete time survival model in which the outcome was the probability of a cow becoming pregnant during a given two day period of risk, and presence or absence of a recorded lameness event during various time frames relative to the risk period amongst the potential explanatory variables. A separate simulation model was then constructed to evaluate the wider clinical implications of the model results (i.e. the potential for a herd’s incidence rate of lameness to influence its overall reproductive performance) using PSA. Although the discrete time survival analysis revealed some relatively large associations between lameness events and risk of pregnancy (for example, occurrence of a lameness case within 14 days of a risk period was associated with a 25% reduction in the risk of the cow becoming pregnant during that risk period), PSA revealed that, when viewed in the context of a realistic clinical situation, a herd’s lameness incidence rate is highly unlikely to influence its overall reproductive performance to a meaningful extent in the vast majority of situations. Construction of a simulation model within a PSA framework proved to be a very useful additional step to aid contextualisation of the results from a discrete time survival model, especially where the research is designed to guide on-farm management decisions at population (i.e. herd) rather than individual level. PMID:25101997
Hudson, Christopher D.; Huxley, Jonathan N.; Green, Martin J.
The objective of this work was to determine the effect of family labour on the profitability and competitiveness of small-scale dairy farms in the highlands of Central Mexico. Economic data from 37 farms were analysed from a stratified statistical sampling with a Neyman assignment. Three strata were defined taking herd size as criterion. Stratum 1: herds from 3 to 9 cows plus replacements, Stratum 2: herds from 10 to 19 cows and Stratum 3: herds from 20 to 30 cows. The policy analysis matrix was used as the method to determine profitability and competitiveness. The coefficient of private profitability (CPP) when the economic cost of family labour is included in the cost structure was 8.0 %, 31.0 % and 46.0 %. When the economic cost of family labour is not included, CPP increase to 47.0 %, 57.0 % and 66.0 % for each strata, respectively. The private cost ratio (PCR) when family labour is included was 0.79, 0.51 and 0.42 for strata 1, 2 and 3, respectively. When family labour is not included, the PCR was 0.07, 0.25 and 0.26. Net profit per litre of milk including family labour was US$0.03 l(-1) for Stratum 1, US$0.09 for Stratum 2 and US$0.12 l(-1) for Stratum 3; but increased to $0.12, 0.14 and 0.15, respectively, when the economic cost of family labour is not included. It is concluded that family labour is a crucial factor in the profitability and competitiveness of small-scale dairy production. PMID:24097246
Posadas-Domínguez, Rodolfo Rogelio; Arriaga-Jordán, Carlos Manuel; Martínez-Castañeda, Francisco Ernesto
An environmental history of High Plains grazing that focused on transhumant sheepherding of New Mexico, watershed cattle ranching of the open range, and barbed-wire stock-farming of the privatized plains--all systems of ...
Kerr, Daniel Stewart
Water conservation using deficit irrigation and dryland cropping systems are being implemented where the Ogallala aquifer limits irrigation capacity. Decreased crop productivity and profitability has encouraged integration of cattle grazing to supplement crop income, but potential soil compaction ma...
In ruminants, methane (CH4) is a by-product of digestion and contributes significantly to the greenhouse gas emissions attributed to agriculture. Grazed grass is a relatively cheap and nutritious feed but herbage species and nutritional quality vary between pastures, with management, land type and season all potentially impacting on animal performance and CH4 production. The objective of this study was to evaluate performance and compare CH4 emissions from cattle of dairy and beef origin grazing two grassland ecosystems: lowland improved grassland (LG) and upland semi-natural grassland (UG). Forty-eight spring-born beef cattle (24 Holstein-Friesian steers, 14 Charolais crossbred steers and 10 Charolais crossbred heifers of 407 (s.d. 29), 469 (s.d. 36) and 422 (s.d. 50) kg BW, respectively), were distributed across two balanced groups that grazed the UG and LG sites from 1 June to 29 September at stocking rates (number of animals per hectare) of 1.4 and 6.7, respectively. Methane emissions and feed dry matter (DM) intake were estimated by the SF6 tracer and n-alkane techniques, respectively, and BW was recorded across three experimental periods that reflected the progression of the grazing season. Overall, cattle grazed on UG had significantly lower (P<0.001) mean daily DM intake (8.68 v. 9.55 kg/day), CH4 emissions (176 v. 202 g/day) and BW gain (BWG; 0.73 v. 1.08 kg/day) than the cattle grazed on LG but there was no difference (P>0.05) in CH4 emissions per unit of feed intake when expressed either on a DM basis (20.7 and 21.6 g CH4 per kg DM intake for UG and LG, respectively) or as a percentage of the gross energy intake (6.0% v. 6.5% for UG and LG, respectively). However, cattle grazing UG had significantly (P<0.001) greater mean daily CH4 emissions than those grazing LG when expressed relative to BWG (261 v. 197 g CH4/kg, respectively). The greater DM intake and BWG of cattle grazing LG than UG reflected the poorer nutritive value of the UG grassland. Although absolute rates of CH4 emissions (g/day) were lower from cattle grazing UG than LG, cattle grazing UG would be expected to take longer to reach an acceptable finishing weight, thereby potentially off-setting this apparent advantage. Methane emissions constitute an adverse environmental impact of grazing by cattle but the contribution of cattle to ecosystem management (i.e. promoting biodiversity) should also be considered when evaluating the usefulness of different breeds for grazing semi-natural or unimproved grassland. PMID:25167210
Richmond, A S; Wylie, A R G; Laidlaw, A S; Lively, F O
Comprehensive inventories of greenhouse gas (GHG) mitigation options for animal agriculture have been published recently. For dairy production systems, management option include (1) manipulation of dietary components (e.g., forages, concentrates) and use of feed additives (e.g., oils, tannins) to re...
The present study addresses potential of water hyacinth for treating small-scale dairy wastewater to satisfy effluent standards for disposal into public sewers. The batch experiments were conducted on dairy wastewater using reactor with water hyacinth and without water hyacinth. The Chemical Oxygen Demand (COD) was varied from 507 mg/L to 4,672 mg/L and the maximum Hydraulic Retention Time (HRT) adopted was 8 days. The loss of water due to evapo-transpiration and evaporation was also measured. The water hyacinth system performed better when initial COD concentration was maintained less than 1,672 mg/L for six days HRT. The performance of water hyacinth system was more effective than reference by 30% to 45% for COD removal. However, water hyacinth had no significant impact in reducing Total Dissolved Solids (TDS). The evapo-transpiration loss was almost double than the evaporation loss. The first order reaction kinetics was applicable and reaction rate parameters were estimated for various organic strengths of wastewater. The reaction rate parameters for water hyacinth system were three times higher than a system without water hyacinth and also found to vary with initial COD values. Water hyacinth can be adopted to treat dairy wastewater from small-scale dairy effectively for disposal into public sewers. PMID:19237765
Munavalli, G R; Saler, P S
High intensity dairy farms produce large amounts of liquid waste that is stored in waste water holding lagoons. The use of circulators to treat waste water is becoming common, and vendors claim that these systems reduce odors, pathogen levels, and alter the chemistry of the waste water such that it ...
Great improvement has been made in the past several years in the quality of optical components used in synchrotron radiation (SR) beamlines. Most of this progress has been the result of vastly improved metrology techniques and instrumentation permitting rapid and accurate measurement of the surface finish and figure on grazing incidence optics. A significant theoretical effort has linked the actual performance of components used as x-ray wavelengths to their topological properties as measured by surface profiling instruments. Next-generation advanced light sources will require optical components and systems to have sub-arc second surface figure tolerances. This paper will explore the consequences of these requirements in terms of manufacturing tolerances to see if the present manufacturing state-of-the-art is capable of producing the required surfaces. 15 refs., 14 figs., 2 tabs.
Takacs, P.Z. (Brookhaven National Lab., Upton, NY (USA)); Church, E.L. (Picatinny Arsenal, Dover, NJ (USA). Army Armament Research, Development and Engineering Center)
A previously described stochastic simulation model of a dairy enterprise was modified for improved robustness. This model was developed to evaluate investments in Precision Dairy Farming technologies and was constructed to embody the biological and economic complexities of a dairy farm system within...
A dynamic, stochastic, mechanistic simulation model of a modern dairy enterprise was developed to evaluate the costs and benefits associated with investments in Precision Dairy Farming (PDF) technologies. The model was designed to represent the biological and economic complexities of a dairy system ...
Eight paired reaches of northeastern Oregon streams were selected such that one reach was an established livestock exclosure and a neighboring, geomorphologically similar reach was open to grazing. Exclosures varied in length from 123 to 436 m. Teams of snorkelers recorded fish species and size-groups in the exclosure and grazed reaches simultaneously so that diurnal changes in fish behavior did
Peter B. Bayley; Hiram W. Li
This study attempts to link factors affecting the demand for Bureau of Land Management grazing to perceived changes in permittee welfare over the 1962-92 period. Annual demand for federal forage is found to be sensitive to active preference, beef cow and breeding ewe inventories, and grazing fees and nonfee allotment utilization costs. No evidence is found to support the notion
David K. Lambert; John Scott Shonkwiler
Grazing permit value supposedly arises as a cost advantage for permit holders. Yet, ranches are overpriced relative to income earning potential. Hedonic models for New Mexico and the Great Basin were used to evaluate permit value. We found less than 16% of the marginal value of grazing permits in New Mexico can be attributed to livestock production, and for Great
Neil R. Rimbey; L. Allen Torell; John A. Tanaka
Properly managed grazing lands provide several positive environmental benefits. The key to sustainability of grazing lands is perennial vegetative cover, which holds soil in place, filters water, and recycles nutrients. Significant changes in vegetation can have subtle to dramatic effects on the pr...
your Winogradsky column. Grazing experiments can also be performed with labeled bacteria, but beads calculations. #12;Lab Procedure: In a 15 ml Falcon tube, incubate 5 ml from your Winogradsky column with 100 lMicrobial Grazing Lab October 20, 2011 The microbial loop is responsible for the cycling
Vallino, Joseph J.
Background The objective of this study was to determine if acute heat stress (HS) decreases milk secretion by activating the milk-borne negative feedback system, as an emergency physiological response to prevent a life-threatening situation. To induce HS, summer acclimatized dairy cows were exposed to full sun under mid-summer Mediterranean conditions, with and without conventional cooling procedures. Results Exposure to HS induced a rapid and acute (within 24 h) reduction in milk yield in proportion to the heat load. This decrease was moderated by cooler night-time ambient temperature. The reduction in milk yield was associated with corresponding responses in plasminogen activator/plasminogen-plasmin activities, and with increased activity (concentration) of the (1–28) N-terminal fragment peptide that is released by plasmin from ?-casein (?-CN (1–28)). These metabolites constitute the regulatory negative feedback system. Previously, it has been shown that ?-CN (1–28) down-regulated milk secretion by blocking potassium channels on the apical aspects of the mammary epithelial cells. Conclusion Here we demonstrate that the potassium channels in mammary tissue became more susceptible to ?-CN (1–28) activity under HS. Thus, the present study highlighted two previously unreported features of this regulatory system: (i) that it modulates rapidly in response to stressor impact variations; and (ii) that the regulations of the mammary epithelial potassium channel sensitivity to the inhibitory effect of ?-CN (1–28) is part of the regulatory system. PMID:19563620
Silanikove, Nissim; Shapiro, Fira; Shinder, Dima
Intensive management is almost the only way to ensure dairy farm profitability. The dry period length (DPL) is a key factor in the productivity and health of dairy cows, but whether the same is true of dairy sheep is unclear. This study investigated the effects of DPL on the performance of Lacaune sheep under intensive management. We recorded 8136 lactations from 4220 ewes on one farm for the period 2005-2010, and data from a total of 6762 complete lactations 1-4 were included in the study. The length of the dry period following the current lactation was studied. The larger the total milk yield (MY) and daily milk yield (DMY), the shorter was the DPL before the next lactation. DPL correlated with MY (r=-0·384), DMY (r=-0·277) and the lambing-to-conception interval (LC; r=0·201, P<0·0001) in the global analysis of all lactations (lactations 1-4). The influence of previous-DPL (P-DPL), or the length of the period prior to the start of the next lactation, was studied for 4318 lactations. P-DPL was classified into five intervals: very short (P-DPL-XS), 1-30 d; short (P-DPL-S), 31-60 d; medium (P-DPL-M), 61-90 d; long (P-DPL-L), 91-120 d; and very long (P-DPL-XL), >120 d. P-DPL positively correlated with lambing-to-next conception interval (LNC; r=0·095, P<0·0001) for lactations 1-4. LNC was significantly shorter for P-DPLs that were very short, short, or long (P-PDL-XS, 144·2±67·8 d; P-PDL-S, 149·1±57·2 d; P-PDL-L, 152·0±53·7 d) than for groups with very long or medium P-PDLs (P-DPL-XL, 161·5±62·9 d; P-DPL-M, 169·0±74·8 d; P<0·0001). Moreover, P-DPLs that were very short, long, or very long were associated with the lowest milk yields (P-PDL-XS, 377±215 l; P-PDL-l, 370±168 l; P-PDL-XL, 396±196 l). These yields were significantly lower than the yields for short and medium P-DPLs (P-DPL-S, 432±187 l; P-DPL-M, 436±191 l; P<0·0001) when averages of lactations 1-4 were analysed. These results indicate that lactations with larger MY are followed by a shorter dry period, and that a dry period of 30-90 d leads to larger yields in the next lactation. The best LNC was associated with the shortest Previous-DPL. Hence, 30-60 d should be the optimal dry period length for Lacaune sheep under intensive conditions. PMID:22850582
Hernandez, Fernando; Elvira, Laura; Gonzalez-Martin, Juan-Vicente; Astiz, Susana
The Pennsylvania State University Department of Dairy and Animal Science provides this site, which contains over 20 full text extension publications (circulars, charts, and tables) in the areas of dairy cattle nutrition, feed management and forage quality. Pertinent slide shows, fourteen nutritional value of forage and concentrate tables, and a growth chart and weight table populate this site. On the lighter side, visitors can download cow images (with explanations of how to turn them into computer wallpaper), and interactive "cow cards" to send to their friends. This is an excellent resource for agricultural extension faculty or agents.
This study investigates the effect of length and cover of track ways between barn and pasture on lameness in Danish dairy cows. We hypothesised that short track distances would be associated with a lower lameness probability of dairy cows compared to longer distances and that track ways with prepared cover (asphalt, gravel, slag, concrete, rubber) compared to no prepared cover (sand, soil and/or grass) would be associated with a lower lameness probability of dairy cows in grazing herds. In total, 2084 dairy cows from 36 herds, grazing their dairy cows during summer, were individually assessed for their lameness status. The cows were further clinically examined for claw conformation and hock integument. Information on breed and parity per cow and size per herd was extracted from a national data base. Track way distance ranged from 0 to 700 m and was categorised as (1) <165 m or (2) ?165 m. Cover of track way was categorised as (1) prepared (asphalt, gravel, slag, concrete, and/or rubber), (2) partly prepared or (3) not prepared (soil, sand, grass) for the surface of the majority of tracks used. The effect of track way distance and cover was evaluated for their impact on lameness using logistic analysis with a multi-level model structure. The probability for lameness did not change with track distance but increased with no (odds 4.0 times higher) or only partly prepared (odds 3.8 times higher) cover compared to prepared cover. In conclusion, we found that having a cover on the track way was associated with decreased severe lameness in Danish dairy cows. PMID:24387936
Burow, E; Thomsen, P T; Rousing, T; Sørensen, J T
Several clinical scoring systems for diagnosis of bovine respiratory disease (BRD) in calves have been proposed. However, such systems were based on subjective judgment, rather than statistical methods, to weight scores. Data from a pair-matched case-control study on a California calf raising facility was used to develop three novel scoring systems to diagnose BRD in preweaned dairy calves. Disease status was assigned using both clinical signs and diagnostic test results for BRD-associated pathogens. Regression coefficients were used to weight score values. The systems presented use nasal and ocular discharge, rectal temperature, ear and head carriage, coughing, and respiratory quality as predictors. The systems developed in this research utilize fewer severity categories of clinical signs, require less calf handling, and had excellent agreement (Kappa > 0.8) when compared to an earlier scoring system. The first scoring system dichotomized all clinical predictors but required inducing a cough. The second scoring system removed induced cough as a clinical abnormality but required distinguishing between three levels of nasal discharge severity. The third system removed induced cough and forced a dichotomized variable for nasal discharge. The first system presented in this study used the following predictors and assigned values: coughing (induced or spontaneous coughing, 2 points), nasal discharge (any discharge, 3 points), ocular discharge (any discharge, 2 points), ear and head carriage (ear droop or head tilt, 5 points), fever (?39.2°C or 102.5°F, 2 points), and respiratory quality (abnormal respiration, 2 points). Calves were categorized “BRD positive” if their total score was ?4. This system correctly classified 95.4% cases and 88.6% controls. The second presented system categorized the predictors and assigned weights as follows: coughing (spontaneous only, 2 points), mild nasal discharge (unilateral, serous, or watery discharge, 3 points), moderate to severe nasal discharge (bilateral, cloudy, mucoid, mucopurlent, or copious discharge, 5 points), ocular discharge (any discharge, 1 point), ear and head carriage (ear droop or head tilt, 5 points), fever (?39.2°C, 2 points), and respiratory quality (abnormal respiration, 2 points). Calves were categorized “BRD positive” if their total score was ?4. This system correctly classified 89.3% cases and 92.8% controls. The third presented system used the following predictors and scores: coughing (spontaneous only, 2 points), nasal discharge (any, 4 points), ocular discharge (any, 2 points), ear and head carriage (ear droop or head tilt, 5 points), fever (?39.2°C, 2 points), and respiratory quality (abnormal respiration, 2 points). Calves were categorized “BRD positive” if their total score was ?5. This system correctly classified 89.4% cases and 90.8% controls. Each of the proposed systems offer few levels of clinical signs and data-based weights for on-farm diagnosis of BRD in dairy calves. PMID:24482759
Love, William J.; Lehenbauer, Terry W.; Kass, Philip H.; Van Eenennaam, Alison L.
Animal grazing on lands near streams has the potential to contribute sediment and nutrients to surface waters. To minimize the impact, we must understand the effects of grazing systems on stream bank erosion. In this study, we used six 12-ha grass pastures that were each bisected by a 141-m stream s...
Previous work has failed to address fully the response of (autotrophic and heterotrophic) respiration to grazing in different ecosystems, particularly in alpine grasslands outside the growing season. From 2010 to 2011 a field experiment combined two methods (static closed chambers and a closed dynamic soil CO2 flux system) in alpine grasslands located in the Tianshan Mountains. We examined the effects of grazing regime on ecosystem respiration (Re) both outside (NGS) and during (GS) the growing season and determined the pattern of Re in relation to climate change. There was no significant change in CO2 emissions under grazing. Heterotrophic respiration (Rh) accounted for 78.5% of Re with short-term grazing exclusion and 93.2% of Re with long-term grazing exclusion. Re, Rh and autotrophic respiration (Ra) fluxes outside the growing season were equivalent to 12.9%, 14.1% and 11.4% of the respective CO2 fluxes during the growing season. In addition, our results indicate that soil water content played a critical role in Ra in the cold and arid environment. Both Rh and Re were sensitive to soil temperature. Moreover, our results suggest that grazing exerted no significant effect on CO2 emissions in these alpine grasslands.
Gong, Y. M.; Mohammat, A.; Liu, X. J.; Li, K. H.; Christie, P.; Fang, F.; Song, W.; Chang, Y. H.; Han, W. X.; Lü, X. T.; Liu, Y. Y.; Hu, Y. K.
Papers are presented on the diffraction-limited performance of grazing incidence optical systems; transverse ray aberrations of Wolter type 1 telescopes; hybrid X-ray telescope systems; surface characterization of grazing incidence optics in the extreme UV and X-ray regions; and the surface roughness properties of synchrotron radiation optics. Topics discussed include the simulation of free-abrasive grinding of grazing incidence mirrors with vertical-honing and flexible blades; mirrors for the Extreme Ultraviolet Explorer; the design and development of conical X-ray imaging mirrors; thermal loading considerations for synchrotron radiation mirrors; and grazing incidence optics for synchrotron radiation insertion-device beams. Consideration is given to the interpretation of glancing incidence scattering measurements; damage processes in short wavelength coated FEL optics; the replication of grain incidence optics; and the assembly and alignment of the Technology Mirror Assembly.
Osantowski, John F. (editor); Van Speybroeck, Leon (editor)
As land becomes a limiting resource for pasture-based dairy farming, the inclusion of purchased supplementary feeds to increase milk production per cow (through greater dry matter intake) and per hectare (through increased stocking rate) is often proposed as a strategy to increase profitability. Although a plausible proposition, virtually no analysis has been done on the effect of such intensification on the profitability of commercial pasture-based dairy farm businesses. The objective of this study was to characterize the average physical and financial performance of dairy systems differing in the proportion of the cow's diet coming from grazed pasture versus purchased supplementary feeds over 4 yr, while accounting for any interaction with geographic region. Physical, genetic, and financial performance data from 1,561 seasonal-calving, pasture-based dairy farms in Ireland were available between the years 2008 and 2011; data from some herds were available for more than 1 yr of the 4-yr study period, providing data from 2,759 dairy farm-years. The data set was divided into geographic regions, based on latitude, rainfall, and soil characteristics that relate to drainage; these factors influence the length of the pasture growth season and the timing of turnout to pasture in spring and rehousing in autumn. Farms were also categorized by the quantity of feed purchased; farms in which cows received <10, 11-20, 21-30, or >30% of their annual feed requirements from purchased feed were considered to be categories representative of increasing levels of system intensification. Geographic region was associated with differences in grazing days, pasture harvested per hectare, milk production per cow and per hectare, and farm profitability. Farms in regions with longer grazing seasons harvested a greater amount of pasture [an additional 19kg of dry matter (DM)/ha per grazing day per hectare], and greater pasture harvested was associated with increased milk component yield per hectare (58.4kg of fat and 51.4kg of protein more per tonne of DM pasture harvested/ha) and net profit per hectare (€268/ha more per tonne of DM harvested). Milk yield and yield of milk components per cow and per hectare increased linearly with increased use of purchased feed (additional 30.6kg of milk fat and 26.7kg of milk protein per tonne of DM purchased feed per hectare), but, on average, pasture harvested/hectare and net profit/hectare declined (-0.60 t of DM/ha and -€78.2/ha, respectively) with every tonne of DM supplementary feed purchased per hectare. The results indicate an effect of purchased feeds not usually accounted for in marginal economic analyses (e.g., milk to feed price ratio): the decline in pasture harvested/hectare, with the costs of producing the unutilized pasture in addition to the cost of feed resulting in a lower profit. In conclusion, greater milk component yields per cow were associated with increased profit per hectare, and a greater use of purchased feeds was associated with an increase in the yield of milk components. However, on average, increasing yield of milk components through the supply of purchased feeds to pasture-based cows was associated with a decline in pasture harvested per hectare and profitability. The decline in pasture harvested per hectare with increased use of purchased supplements per cow is probably the primary reason for the low milk production response and the failure to capitalize on the potential benefits of purchased supplements, with the associated costs of growing the unutilized pasture, in conjunction with increased nonfeed variable and fixed costs outweighing the increased milk production and revenue from supplementation. Farmers considering intensification through use of purchased supplements to increase the stock-carrying capacity of the farm (i.e., stocking rate) must ensure that they focus on management of pasture and total cost control to capture the potential benefits of supplementary feed use. PMID:25747836
Ramsbottom, G; Horan, B; Berry, D P; Roche, J R
We did a test-retest study on 21 farms to assess the repeatability of the Dairy Heifer Health Report of the National Dairy Heifer Evaluation Project. The median retest interval was 42 days (range 14–63 days), retest interviewers were blinded as to responses on the first visits, and all date-specific questions were anchored to the dates of the first tests. The
H. N. Erb; A. J. Heinrichs; R. E. Woods; W. M. Sischo
...volatility and dairy farmer profitability, and review various industry proposals and analysis. The Dairy Committee...volatility and dairy farmer profitability. The Dairy Committee...volatility and dairy farmer profitability, and...
... that are designed so that young children cannot open them. Finally, many dairy operators simply are not aware of how dangerous these caustics are. Please share this information with others – but don’t stop there. Awareness of the danger is not enough. Take one ...
Machair grassland uniquely occurs over sandy, calcareous soils of coastal sand-plains in dune systems of north-western Scotland and Ireland. This study assesses the plant species composition of Irish machair grassland at a landscape-scale. Machair sites were sampled with quadrats and multivariate analysis was used to assess relationships between species abundance, soil physical variables, livestock grazing and recreation activity. Grazing by
A. Cooper; T. McCann; E. Ballard
Water to air methane emissions from freshwater reservoirs can be dominated by sediment bubbling (ebullitive) events. Previous work to quantify methane bubbling from a number of Australian sub-tropical reservoirs has shown that this can contribute as much as 95% of total emissions. These bubbling events are controlled by a variety of different factors including water depth, surface and internal waves, wind seiching, atmospheric pressure changes and water levels changes. Key to quantifying the magnitude of this emission pathway is estimating both the bubbling rate as well as the areal extent of bubbling. Both bubbling rate and areal extent are seldom constant and require persistent monitoring over extended time periods before true estimates can be generated. In this paper we present a novel system for persistent monitoring of both bubbling rate and areal extent using multiple robotic surface chambers and adaptive sampling (grazing) algorithms to automate the quantification process. Individual chambers are self-propelled and guided and communicate between each other without the need for supervised control. They can maintain station at a sampling site for a desired incubation period and continuously monitor, record and report fluxes during the incubation. To exploit the methane sensor detection capabilities, the chamber can be automatically lowered to decrease the head-space and increase concentration. The grazing algorithms assign a hierarchical order to chambers within a preselected zone. Chambers then converge on the individual recording the highest 15 minute bubbling rate. Individuals maintain a specified distance apart from each other during each sampling period before all individuals are then required to move to different locations based on a sampling algorithm (systematic or adaptive) exploiting prior measurements. This system has been field tested on a large-scale subtropical reservoir, Little Nerang Dam, and over monthly timescales. Using this technique, localised bubbling zones on the water storage were found to produce over 50,000 mg m-2 d-1 and the areal extent ranged from 1.8 to 7% of the total reservoir area. The drivers behind these changes as well as lessons learnt from the system implementation are presented. This system exploits relatively cheap materials, sensing and computing and can be applied to a wide variety of aquatic and terrestrial systems.
Grinham, Alistair; Dunbabin, Matthew
Browsing (i.e., eating woody and non-woody dicotyledonous plants) and grazing (i.e., eating grass) are distinctively different\\u000a types of feeding behaviour among ungulates today. Ungulates with different diets have different morphologies (both craniodental\\u000a ones and in aspects of the digestive system) and physiologies, although some of these differences are merely related to body\\u000a size, as grazers are usually larger than browsers.
Research on grazing effects usually compares the same sites through time or grazed and ungrazed sites over the same time period. Both approaches are complicated in arid environments where grazing can have a long undocumented history and landscapes can be spatially heterogenous. This work employs both approaches simultaneously by comparing grazed and ungrazed samples through both time and space using
J. Fisher; K. L. Cole; R. S. Anderson
Successional trajectories through the statistical space of ordinations were used to examine response to grazing in salt desert shrub communities of western Utah, USA. Relative cover data were periodically collected over a 53 year period from grazing exclosures and pastures grazed with light or heavy stocking rates in fall or spring (4 grazing treatments). Two-way indicator species analysis was used
S. G. Whisenant; F. J. Wagstaff
Summary The relation between density of rabbit populations and plant species diversity is discussed. In the dunes of the Dutch Frisian Island of Schiermonnikoog, the rabbit grazing pressure has been quantified on the basis of traces of recent grazing activity. Moderate grazing turned out to bring about maximal species richness. Current changes in grazing pressure (either decrease or increase) can
H. J. Zeevalking; L. F. M. Fresco
Salmonellae continue to be a major concern for the dairy industry because these bacteria have caused recent outbreaks of illness and have been isolated from various dairy products in the market place. Salmonellae are generally not heat resistant and normally grow at 35 to 37 degrees C, but they can grow at much lower temperatures, provided that the incubation time is suitably extended. To minimize problems, foods should be held at or below 2 to 5 degrees C at all times. Both conventional and rapid methods are available to isolate salmonellae from dairy foods and to identify the bacteria. Salmonellae behave differently in different kinds of cheese: they survived in ripening Cheddar cheese for up to 7 mo at 13 degrees C and for 10 mo at 7 degrees C; in coldpack cheese food for several weeks, depending on the pH and preservative used; and in Domiati cheese 13 to 36 d, depending on the manufacturing process used. When Mozzarella cheese was made, temperatures of stretching and molding (60 degrees C) killed all salmonellae present, but, in cottage cheese, survival of the pathogen depended on the cooking temperature of curd. Spray drying of skim milk killed substantial numbers of salmonellae, but some survivors remained. Butter readily supported growth of salmonellae at room temperature, and neither freezing nor refrigeration for brief periods eliminated salmonellae from butter. Use of appropriate hygienic procedures, e.g., Hazard Analysis Critical Control Point system, during processing should reduce the likelihood of salmonellosis outbreaks associated with dairy foods. PMID:1452840
el-Gazzar, F E; Marth, E H
An efficient, electrically driven freeze concentration system offers potential for substantially increasing electricity demand while providing the mature dairy industry with new products for domestic and export markets together with enhanced production efficiencies. Consumer tests indicate that dairy products manufactured from freeze-concentrated ingredients are either preferred or considered equivalent in quality to fresh milk-based products. Economic analyses indicate that this technology should be competitive with thermal evaporation processes on a commercial basis.
Best, D.E.; Vasavada, K.C.
Predation of attached Pseudomonas putida mt2 by the small ciliate Tetrahymena sp. was investigated with a percolated column system. Grazing rates were examined under static and dynamic conditions and were compared to grazing rates in batch systems containing suspended prey. The prey densities were 2 × 108 bacteria per ml of pore space and 2 × 108 bacteria per ml of suspension, respectively. Postingestion in situ hybridization of bacteria with fluorescent oligonucleotide probes was used to quantify ingestion. During 30 min, a grazing rate of 1,382 ± 1,029 bacteria individual?1 h?1 was obtained with suspended prey; this was twice the grazing rate observed with attached bacteria under static conditions. Continuous percolation at a flow rate of 73 cm h?1 further decreased the grazing rate to about 25% of the grazing rate observed with suspended prey. A considerable proportion of the protozoans fed on neither suspended bacteria nor attached bacteria. The transport of ciliates through the columns was monitored at the same time that predation was monitored. Less than 20% of the protozoans passed through the columns without being retained. Most of these organisms ingested no bacteria, whereas the retained protozoans grazed more efficiently. Retardation of ciliate transport was greater in columns containing attached bacteria than in bacterium-free columns. We propose that the correlation between grazing activity and retardation of transport is a consequence of the interaction between active predators and attached bacteria. PMID:9546161
Eisenmann, Heinrich; Harms, Hauke; Meckenstock, Rainer; Meyer, Elisabeth I.; Zehnder, Alexander J. B.
Access to an evaporative cooling system can increase production in dairy cows because of improved thermal comfort. This study aimed to evaluate the impact of ambient temperature on thermoregulation, plasma cortisol, insulin-like growth factor 1 (IGF-I), and productive status, and to determine the efficiency of an evaporative cooling system on physiological responses under different weather patterns. A total of 28 Holstein cows were divided into two groups, one with and the other without access to a cooling system with fans and mist in the free stall. The parameters were analyzed during morning (0700 hours) and afternoon milking (1430 hours) under five different weather patterns throughout the year (fall, winter, spring, dry summer, and rainy summer). Rectal temperature (RT), body surface temperature (BS), base of tail temperature (TT), and respiratory frequency (RF) were lower in the morning ( P < 0.01). The cooling system did not affect RT, and both the groups had values below 38.56 over the year ( P = 0.11). Cortisol and IGF-I may have been influenced by the seasons, in opposite ways. Cortisol concentrations were higher in winter ( P < 0.05) and IGF-I was higher during spring-summer ( P < 0.05). The air temperature and the temperature humidity index showed positive moderate correlations to RT, BS, TT, and RF ( P < 0.001). The ambient temperature was found to have a positive correlation with the physiological variables, independent of the cooling system, but cooled animals exhibited higher milk production during spring and summer ( P < 0.01).
Titto, Cristiane Gonçalves; Negrão, João Alberto; Titto, Evaldo Antonio Lencioni; Canaes, Taissa de Souza; Titto, Rafael Martins; Pereira, Alfredo Manuel Franco
Access to an evaporative cooling system can increase production in dairy cows because of improved thermal comfort. This study aimed to evaluate the impact of ambient temperature on thermoregulation, plasma cortisol, insulin-like growth factor 1 (IGF-I), and productive status, and to determine the efficiency of an evaporative cooling system on physiological responses under different weather patterns. A total of 28 Holstein cows were divided into two groups, one with and the other without access to a cooling system with fans and mist in the free stall. The parameters were analyzed during morning (0700 hours) and afternoon milking (1430 hours) under five different weather patterns throughout the year (fall, winter, spring, dry summer, and rainy summer). Rectal temperature (RT), body surface temperature (BS), base of tail temperature (TT), and respiratory frequency (RF) were lower in the morning (P < 0.01). The cooling system did not affect RT, and both the groups had values below 38.56 over the year (P = 0.11). Cortisol and IGF-I may have been influenced by the seasons, in opposite ways. Cortisol concentrations were higher in winter (P < 0.05) and IGF-I was higher during spring-summer (P < 0.05). The air temperature and the temperature humidity index showed positive moderate correlations to RT, BS, TT, and RF (P < 0.001). The ambient temperature was found to have a positive correlation with the physiological variables, independent of the cooling system, but cooled animals exhibited higher milk production during spring and summer (P < 0.01). PMID:22580965
Titto, Cristiane Gonçalves; Negrão, João Alberto; Titto, Evaldo Antonio Lencioni; Canaes, Taissa de Souza; Titto, Rafael Martins; Pereira, Alfredo Manuel Franco
In this cross-sectional study, we assessed and mapped the seroprevalence of brucellosis in small-scale dairy farming in an urban and peri-urban area of Tajikistan and investigated factors associated with seropositivity. As urban and peri-urban farming is both an opportunity to improve the livelihood for small-scale farmers and a potential public health hazard, studies are warranted to reveal possible peculiarities in the epidemiology of brucellosis in this type of dairy farming. In total, 904 cows of breeding age belonging to 443 herds in 32 villages were serologically tested with indirect enzyme-linked immunosorbent assay (ELISA) and positive samples confirmed with competitive ELISA. Two logistic regression models were used to investigate an association between seropositivity and risk factors at herd and individual level. The herd and individual seroprevalences were 4.1 and 2.0 %, respectively. Herds with a history of abortions were found to be associated with seropositivity [odds ratio (OR)?=?5.3; 95 % confidence interval (CI), 1.3-21.3]. Large herds with more than eight cattle were more likely to be seropositive compared to smaller herds with one to two cattle (OR?=?13.9; 95 % CI, 1.6-119). The number of calves produced per cow (indicating age) was found to be associated with seropositivity. Younger cows with one to two produced calves were less likely to be seropositive compared to older cows with more than six produced calves (OR?=?0.24; 95 % CI, 0.06-1.0). Neither introduction of new cattle to the herd nor communal grazing was associated with seropositivity. This study shows that infection with Brucella (1) is present in small-scale urban and peri-urban dairy farming in Tajikistan and (2) has significant negative effects on reproductive performance in this farming system and (3) that some previously known risk factors for seropositivity in rural farming system were absent here. PMID:24414248
Lindahl, Elisabeth; Sattorov, Nosirjon; Boqvist, Sofia; Sattori, Izzatullo; Magnusson, Ulf
We investigated the influence of long-term (56 years) grazing on organic and inorganic carbon (C) and nitrogen (N) contents of the plant-soil system (to 90 cm depth) in shortgrass steppe of northeastern Colorado. Grazing treatments included continuous season-long (May-October) grazing by yearling heifers at heavy (60-75% utilization) and light (20-35% utilization) stocking rates, and nongrazed exclosures. The heavy stocking rate resulted in a plant community that was dominated (75% of biomass production) by the C4 grass blue grama (Bouteloua gracilis), whereas excluding livestock grazing increased the production of C3 grasses and prickly pear cactus (Opuntia polycantha). Soil organic C (SOC) and organic N were not significantly different between the light grazing and nongrazed treatments, whereas the heavy grazing treatment was 7.5 Mg ha(-1) higher in SOC than the nongrazed treatment. Lower ratios of net mineralized N to total organic N in both grazed compared to nongrazed treatments suggest that long-term grazing decreased the readily min