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Effect of urea supplemented and urea treated straw based diet on milk urea concentration in crossbred Karan-Fries cows  

Microsoft Academic Search

The study was undertaken to evaluate the effect of urea supplemented and urea treated straw based diet on milk urea concentration. Six multiparous crossbred Karan-Fries (Holstein Friesian ? Tharparkar) cows were blocked into three groups of nearly equal body weight, DIM, milk yield and milk fat content and were randomized into a 3 ? 3 Latin square design with 3-week

Arindam Dhali; Ram Kumar Mehla; Sunil Kumar Sirohi



Factors Associated with Milk Urea Concentrations in Ontario Dairy Cows  

Microsoft Academic Search

All DHI test-day data, including milk urea concentra- tions measured by infrared test method, were collected from 60 commercial Ontario Holstein dairy herds for a 13-mo period between December 1, 1995, and December 31, 1996. The objectives of this study were to describe the relationships between milk urea concentrations and seasonal factors, sampling factors, cow factors, and test- day production

S. M. Godden; K. D. Lissemore; D. F. Kelton; K. E. Leslie; J. S. Walton; J. H. Lumsden



Cow level sampling factors affecting analysis and interpretation of milk urea concentrations in 2 dairy herds.  

PubMed Central

The goals of this study were to determine the influence of the variations among udder quarters, the somatic cell count, the time of sampling during the day, sample conservation, and centrifugation on milk urea (UREA) concentrations, and to propose a sample collection procedure for herds that are not on a Dairy Herd Improvement (DHI) program. Forty cows from 2 herds with different feeding practices were randomly selected. The quarter sampled and the somatic cell count did not significantly influence UREA concentrations. Milk urea concentrations were highest in the morning. The diurnal pattern was not influenced by intrinsic factors like parity, days postpartum, or daily milk yield. The UREA concentrations were significantly higher after refrigeration for one week (mean UREA change = +0.41 +/- 0.24 mmol/L, P = 0.0001) and freezing for one month (mean UREA change = +1.52 +/- 1.25 mmol/L, P = 0.0001). Urea concentrations were slightly higher in lactoserum than in whole milk (mean UREA difference = +0.17 +/- 0.24 mmol/L, P = 0.0001). Although this study included only 2 herds and does not allow extrapolation, differences were found in the diurnal pattern of UREA in these 2 herds, which possibly reflect differences in feeding strategy. With consideration of these results, a 6-point sampling procedure for herds that are not on a DHI program is proposed.

Eicher, R; Bouchard, E; Tremblay, A



Urea concentration in collared peccary milk as an indicator of protein nutritional status.  


Milk urea nitrogen (UN) concentration was examined as a possible index to protein-energy intake in female collared peccaries (Tayassu tajacu). Captive adults were bred and assigned to one of four experimental diets through gestation and lactation. Females fed a high protein diet produced milk with UN concentrations exceeding those of low-protein-fed females. A low energy intake tended to elevate UN concentrations in milk. PMID:3625919

Lochmiller, R L; Hellgren, E C; Grant, W E; Varner, L W



Genetic parameters for milk urea concentration and milk traits in Polish Holstein-Friesian cows.  


Milk urea concentration (MU) used by dairy producers for management purposes can be affected by selection for milk traits. To assess this problem, genetic parameters for MU in Polish Holstein-Friesian cattle were estimated for the first three lactations. The genetic correlation of MU with milk production traits, lactose percentage, fat to protein ratio (FPR) and somatic cell score (SCS) were computed with two 5-trait random regression test-day models, separately for each lactation. Data used for estimation (159,044 daily observations) came from 50 randomly sampled herds. (Co)variance components were estimated with the Bayesian Gibbs sampling method. The coefficient of variation for MU in all three parities was high (40-41 %). Average daily heritabilities of MU were 0.22 for the first parity and 0.21 for the second and third lactations. Average genetic correlations for different days in milk in the first three lactations between MU and other traits varied. They were small and negative for protein percentage (from -0.24 to -0.11) and for SCS (from -0.14 to -0.09). The weakest genetic correlation between MU and fat percentage, and between MU and lactose percentage were observed (from -0.10 to 0.10). Negative average genetic correlation with the fat to protein ratio was observed only in the first lactation (-0.14). Genetic correlations with yield traits were positive and ranged from low to moderate for protein (from 0.09 to 0.33), fat (from 0.16 to 0.35) and milk yield (from 0.20 to 0.42). These results suggest that the selection on yield traits and SCS tends to increase MU slightly. PMID:23934506

Rzewuska, Katarzyna; Strabel, Tomasz



Association Between Live Body Weight and Milk Urea Concentration in Holstein Cows  

Microsoft Academic Search

Use of milk urea (MU) concentration as a parameter for detection of nutritional imbalances requires identi- fication and quantification of nutritional and nonnutri- tional factors that influence it. The objective of this study was to assess the relationship between live body weight (BW) and MU concentration in Holstein cows. Results for the test-day measurements at 7 dairy farms were obtained

D. Hojman; M. Gips; E. Ezra



Evaluation of Dietary Nitrogen Utilization in Dairy Cows Based on Urea Concentrations in Blood, Urine and Milk, and on Urinary Concentration of Purine Derivatives  

Microsoft Academic Search

The effects of level and degradability of dietary protein on urea in blood, urine and milk, and on the urinary purine derivatives and creatinine in dairy cows, were studied. Diurnal variation in urinary concentration of urea, allantoin and creatinine was also studied. A total of 24 multiparous lactating dairy cows were selected from a production experiment and divided into two

Horacio Leandro Gonda; Jan Erik Lindberg



Milk urea nitrogen concentration: heritability and genetic correlations with reproductive performance and disease.  


The objectives of this study were to estimate the heritability of milk urea nitrogen (MUN) concentration and describe the genetic relationship between MUN and reproductive performance and between MUN and diseases in Holsteins. Dairy Records Management Systems (Raleigh, NC) provided lactation data. The Danish Agricultural Advisory Center provided breeding value estimates for diseases. Infrared (IR) and wet chemistry (WC) data were analyzed separately. Heritabilities and genetic correlations for 2 different measures of MUN and reproductive performance were estimated with an animal model using ASREML. Heritabilities for MUN were estimated using all lactations combined (lactations 1 through 5) and separately for first lactation and second lactation. Genetic correlations with reproduction and health were estimated separately for parities 1 and 2. Herd-test-day or herd-year-season along with age at calving and days in milk were included as fixed effects in all models. Heritability estimates for all lactations combined were 0.15 for WC MUN and 0.22 for IR MUN. Genetic correlations between WC MUN and 2 measures of reproductive performance, days to first service, and first service conception were not different from zero. In contrast, the genetic correlation between WC MUN and days open of 0.21 in first lactation and 0.41 in second lactation indicated that higher WC MUN values were associated with increased days open. Correlations among estimated breeding values for MUN and estimated breeding values for Danish diseases identified no significant relationships. Although the results of this study indicate that heritable variation for MUN exists, the inability to identify significant genetic relationships with several measures of disease or reproductive performance appears to limit the value of MUN in selection for disease resistance and improved reproduction. PMID:16291635

Mitchell, R G; Rogers, G W; Dechow, C D; Vallimont, J E; Cooper, J B; Sander-Nielsen, U; Clay, J S



Diurnal Variation of Rumen Ammonia, Serum Urea, and Milk Urea in Dairy Cows at High and Low Yields1  

Microsoft Academic Search

ABSTRACT Milk urea content as an indicator of nutritional status may,be a useful tool if major,sources of variation are consid- ered. Blood and milk samples were col- lected frequently during 16 to 19 h from four Holstein cows to study diurnal vari- ation of urea content. Corn silage, alfalfa hay, and concentrates were fed. Rumen ammonia, VFA, and pH were

D. L. Palmquist



Analytic Validation of an Infrared Milk Urea Assay and Effects of Sample Acquisition Factors on Milk Urea Results  

Microsoft Academic Search

The objective of this study was to determine if milk samples, as they are routinely collected by Ontario Dairy Herd Improvement, would yield accurate milk urea results with an infrared assay. This investigation involved analytic validation of the infrared assay and assessment of the effect of DHI routine sample acquisi- tion factors on milk urea results. Analytic validation of an

S. M. Godden; K. D. Lissemore; D. F. Kelton; J. H. Lumsden; K. E. Leslie; J. S. Walton



Plasma and Milk Urea Nitrogen in Relation to Pregnancy Rate in Lactating Dairy Cattle  

Microsoft Academic Search

The objectives of this study were to relate concentrations of plasma (PUN) and milk (MUN) urea nitrogen to pregnancy rate in dairy cows and compare various methods of analysis and prepara- tion of milk for measuring MUN. In two experiments, blood or milk samples were collected on the day of AI from Holstein cows (n = 160 and n =

W. R. Butler; J. J. Calaman; S. W. Beam



Wood plastic composite at different urea concentrations  

NASA Astrophysics Data System (ADS)

Wood plastic composite (WPC) has been prepared with a low grade wood simul (Salmalia malabarica) of Bangladesh under Co-60 gamma irradiation using MMA as the bulk monomer combined with methanol as the swelling solvent at different urea concentrations. Effect of a second solute such as NVP, TPGDA and TMPTA in the impregnating solution is evaluated. NVP appears to be the best co-additive/second solute among all the additives used to yield the composite with the highest polymer loading (PL) and tensile strength (TS) at 0.5% urea concentration.

Husain, M. M.; Khan, Mubarak A.; Ali, K. M. Idriss; Hasan, A. J. M. Moynul



Effects of Yucca shidigera Extract and Soluble Protein on Performance of Cows and Concentrations of Urea Nitrogen in Plasma and Milk1  

Microsoft Academic Search

Twelve multiparous Holstein cows averaging 122 d postpartum were used in a replicated Latin square design with 21-d periods. Cows were fed diets contain- ing either low or high soluble protein supplemented with 0 or 9 g\\/d of Yucca shidigera extract per cow. Dry matter intake and yields of milk, fat, 3.5% fat- corrected milk, and total solids were not

R. C. Wilson; T. R. Overton; J. H. Clark



Relationships between milk urea and production, nutrition, and fertility traits in Israeli dairy herds.  


The objectives of this study were to identify and evaluate production and environmental factors that influence milk urea (MU) in Israeli dairy herds, to analyze the relationships between MU concentration and nutritional variables, and to examine a possible association between MU and pregnancy rate (PR). Production and environmental data were obtained from the Israeli Dairy Herd Improvement (DHI) Center (n = 1,279,600). Programmed total mixed rations (feeds and quantities) on milk-test day were collected from 42 dairy herds. Data on 36,073 cows that were inseminated close to milk-test day and pregnancy diagnosis results were obtained from the DHI data bank. Highly significant positive relationships were found between MU concentration and milk yield and fat percentage; relationships between MU and milk total protein percentage and somatic cell count were negative. Milk urea levels were higher during the summer months and were higher for adult cows. These levels increased as lactation progressed. Milk urea was positively associated with dietary levels of crude protein, ruminal digestible protein, and neutral detergent fiber contents; it was negatively associated with ration energy and nonstructural carbohydrate contents. Significant influences of specific feeds on MU were detected. A significant negative association was found between MU level and PR. Least squares means for PR for cows in the lowest and highest MU quartiles were 38.4 and 36.1%, respectively. Increasing levels of MU were negatively related to reproductive performance of dairy cows, but the risk of nonpregnancy caused by high levels of MU was lower than reported in previous studies. PMID:15259235

Hojman, D; Kroll, O; Adin, G; Gips, M; Hanochi, B; Ezra, E



Relationships among milk urea-nitrogen, dietary parameters, and fecal nitrogen in commercial dairy herds  

PubMed Central

Our study objective was to determine the ability of milk urea-nitrogen concentrations ([MUN]) to predict fecal nitrogen concentrations ([Fecal N]) in commercial dairy herds. A total of 83 dairy herds were each visited 3 times within 48 h after a monthly herd milk test. For each farm visit, forages were sampled for nutrient analyses, which were entered into a computerized ration evaluator, and fecal samples were taken per rectum from each of 6 cows (2 early-, 2 mid-, and 2 late-lactation). Fecal samples were pooled, mixed, and analyzed for nitrogen content. Fecal nitrogen concentrations were compared with the routinely measured nutritional parameters from the ration evaluation, and the herd average [MUN] for the previous milk test date using mixed linear regression analyses. Total protein supplied in the ration was significantly positively associated with [Fecal N], but herd average [MUN] was not associated (P > 0.10) with [Fecal N].

Arunvipas, Pipat; VanLeeuwen, John A.; Dohoo, Ian R.; Keefe, Greg P.; Burton, Shelley A.; Lissemore, Kerry D.



A compact miniaturized continuous flow system for the determination of urea content in milk.  


A multicommutation-based flow system with photometric detection was developed, employing an analytical microsystem constructed with low temperature co-fired ceramics (LTCC) technology, a solid-phase reactor containing particles of Canavalia ensiformis DC (urease source) immobilized with glutaraldehyde, and a mini-photometer coupled directly to the microsystem which monolithically integrates a continuous flow cell. The determination of urea in milk was based on the hydrolysis of urea in the solid-phase reactor and the ammonium ions produced were monitored using the Berthelot reaction. The analytical curve was linear in the urea concentration range from 1.0 x 10(-4) to 5.0 x 10(-3) mol L(-1) with a limit of detection of 8.0 x 10(-6) mol L(-1). The relative standard deviation (RSD) for a 2.0 x 10(-3) mol L(-1) urea solution was lower than 0.4% (n = 10) and the sample throughput was 13 h(-1). To check the reproducibility of the flow system, calibration curves were obtained with freshly prepared solutions on different days and the RSD obtained was 4.7% (n = 6). Accuracy was assessed by comparing the results of the proposed method with those from the official procedure and the data are in close agreement, at a 95% confidence level. PMID:20694810

Suarez, Willian Toito; Pessoa-Neto, Osmundo Dantas; Dos Santos, Vagner Bezerra; de Araujo Nogueira, Ana Rita; Faria, Ronaldo Censi; Fatibello-Filho, Orlando; Puyol, Mar; Alonso, Julián



Relationships between dietary factors and milk urea nitrogen level in goats grazing herbaceous pasture  

Microsoft Academic Search

This investigation aimed to individuate the dietary factors affecting the milk urea nitrogen (MUN) con- centration in goats grazing herbaceous pasture and, particularly, to verify the relationship linking the diet crude protein (CP) content to MUN. A total of 205 individual observations regarding dietary and milk variables of 37 Girgentana goats involved in two experiments were used. Goats, averaging 154±14

Adriana Bonanno; Massimo Todaro; Antonino Di Grigoli; Maria Luisa Scatassa; Gabriele Tornambé; Maria Luigia Alicata



21 CFR 131.115 - Concentrated milk.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Concentrated milk. 131.115 Section 131.115 Food and...CONTINUED) FOOD FOR HUMAN CONSUMPTION MILK AND CREAM Requirements for Specific Standardized Milk and Cream § 131.115 Concentrated...



Measurement of urea and ammonium concentrations in gastric juice  

Microsoft Academic Search

AIM--To study the effect of known interference in the measurement of urea and ammonium concentrations in samples of gastric juice. METHODS--The effect of pH and ammonium concentration on the o-pthalaldehyde method, the diacetylmonoxime method, a Berthelot linked method and an enzymatic urease method for the measurement of urea in gastric juice was therefore conducted. An enzymatic method of the measurement

W D Neithercut; A M el Nujumi; K E McColl



Measurement of urea and ammonium concentrations in gastric juice.  

PubMed Central

AIM--To study the effect of known interference in the measurement of urea and ammonium concentrations in samples of gastric juice. METHODS--The effect of pH and ammonium concentration on the o-pthalaldehyde method, the diacetylmonoxime method, a Berthelot linked method and an enzymatic urease method for the measurement of urea in gastric juice was therefore conducted. An enzymatic method of the measurement of ammonium in gastric juice was also assessed. RESULTS--The o-pthalaldehyde and the enzymatic urease methods were unaffected by a low gastric juice pH, ammonium concentrations of 10 mmol/l, and had interassay coefficients of variation of 3.9-5.6% and 2.8-10.6%, respectively, over a urea concentration of 2.5 mmol/l-20 mmol/l. The Berthelot linked method resulted in low gastric juice urea concentrations. The enzymatic method of ammonium measurement also proved suitable when the effect of low gastric juice pH was controlled. CONCLUSION--Interference by low pH did not explain the differences in reports of gastric juice urea or ammonium concentrations.

Neithercut, W D; el Nujumi, A M; McColl, K E



Milk cortisol concentration in automatic milking systems compared with auto-tandem milking parlors.  


Milk cortisol concentration was determined under routine management conditions on 4 farms with an auto-tandem milking parlor and 8 farms with 1 of 2 automatic milking systems (AMS). One of the AMS was a partially forced (AMSp) system, and the other was a free cow traffic (AMSf) system. Milk samples were collected for all the cows on a given farm (20 to 54 cows) for at least 1 d. Behavioral observations were made during the milking process for a subset of 16 to 20 cows per farm. Milk cortisol concentration was evaluated by milking system, time of day, behavior during milking, daily milk yield, and somatic cell count using linear mixed-effects models. Milk cortisol did not differ between systems (AMSp: 1.15 +/- 0.07; AMSf: 1.02 +/- 0.12; auto-tandem parlor: 1.01 +/- 0.16 nmol/L). Cortisol concentrations were lower in evening than in morning milkings (1.01 +/- 0.12 vs. 1.24 +/- 0.13 nmol/L). The daily periodicity of cortisol concentration was characterized by an early morning peak and a late afternoon elevation in AMSp. A bimodal pattern was not evident in AMSf. Finally, milk cortisol decreased by a factor of 0.915 in milking parlors, by 0.998 in AMSp, and increased by a factor of 1.161 in AMSf for each unit of ln(somatic cell count/1,000). We conclude that milking cows in milking parlors or AMS does not result in relevant stress differences as measured by milk cortisol concentrations. The biological relevance of the difference regarding the daily periodicity of milk cortisol concentrations observed between the AMSp and AMSf needs further investigation. PMID:16899678

Gygax, L; Neuffer, I; Kaufmann, C; Hauser, R; Wechsler, B



Short communication Effects of dietary urea levels on milk protein fractions of Holstein cows  

Microsoft Academic Search

The aim of this study was to evaluate the effects of substituting soybean meal for urea on milk protein fractions (casein, whey protein and non-protein nitrogen) of dairy cows in three dietary lev- els. Nine mid-lactation Holstein cows were used in a 3 × 3 Latin square arrangement, composed of 3 treatments, 3 periods of 21 days each, and 3

A. A. Aquino; Y. V. R. Lima; B. G. Botaro; C. S. S. Alberto; K. C. Peixoto Jr; M. V. Santos


Economic Analysis of Alternative Milk Concentration Methods.  

National Technical Information Service (NTIS)

Rapidly increasing energy costs dictate a reappraisal of present methods of transporting fluid milk between surplus and deficit regions. Methods which permit transportation of a concentrated product which can be reconstituted to a whole fluid product near...

E. Jesse



Salvage of blood urea nitrogen in sheep is highly dependent on plasma urea concentration and the efficiency of capture within the digestive tract  

Microsoft Academic Search

The aims of this study were 1) to deter- mine whether transfer of blood urea to the gastrointes- tinal tract (GIT) or the efficiency of capture of urea N within the GIT is more limiting for urea N salvage, and 2) to establish the relationship between plasma urea concentration and recycling of urea N to the GIT. We used an

N. E. Sunny; S. L. Owens; R. L. Baldwin VI; S. W. El-Kadi; R. A. Kohn; B. J. Bequette



Estrone and estrone sulfate concentrations in milk and milk fractions.  


Dairy products naturally contain estrogens, and some consumer groups contend these estrogens cause adverse health effects. The objectives of this research were to characterize estrone (E(1)) and estrone sulfate (E(1)S) concentrations in milk from a large number of individual cows, in skim and fat fractions of milk, and in retail milk to provide food and nutrition practitioners with information to estimate potential consumption. Milk was from Holstein cows. Data are presented as means and standard deviations. Analysis of variance was used to determine differences in E(1) and E(1)S content of whole milk and its skim and fat fractions. Mean E(1) and E(1)S concentrations (n=173 cows) were 7.0±12.7 and 46.7±62.1 pg/mL (25.89±46.96 and 172.74±229.71 pmol/L), respectively. Analysis of milk fractions (n=50 samples) demonstrated that 55% of E(1) and 14% of E(1)S were associated with the fat fraction with the remainder associated with the skim fraction. Concentrations of E(1) and E(1)S in pasteurized-homogenized whole milk (n=8) averaged 10.3±0.6 and 85.9±7.3 pg/mL (38.09±2.22 and 317.74±27.00 pmol/L), respectively. Production rates of E(1) plus estradiol in human beings range from 54,000 to 630,000 ng/day. US Food and Drug administration guidelines state that no physiologic effects occur when consumption is ?1% of the endogenous quantities produced by the segment of the population with the lowest daily production. This threshold value for intake would be 540 ng/day. Estimated total E(1) intake from three servings of whole milk was 68 ng/day, which represents 0.01% to 0.1% of daily production rates in human beings. These findings support levels below the current guidelines for safe consumption. PMID:22561023

Macrina, Ann L; Ott, Troy L; Roberts, Robert F; Kensinger, Ronald S



Enzymatic determination of urea in milk by sequential injection with spectrophotometric and conductometric detection.  


In this work, an analytical system based on the coupling of gas diffusion separation and sequential injection analysis for urea determination in milk is presented. A versatile manifold that could simultaneously be used for either spectrophotometric or conductometric detection was constructed. The sample and urease solution are sequentially aspirated into the holding coil and sent to a thermoreactor, where urea is enzymatically hydrolyzed by urease and converted into ammonium. This stream merges an alkaline solution at a confluence point where ammonia is formed. Ammonia diffuses through a hydrophobic membrane and modifies the bromothymol blue indicator color, when spectrophotometric detection is used, or changes the conductance of a boric acid solution acceptor stream, when conductometric detection is used. This methodology was applied to the determination of urea in 18 milk samples and the results were statistically comparable with those furnished by the enzymatic recommended procedure. The detection limits were 2.6 x 10(-4) and 2.8 x 10(-5) mol L(-1) for conductometric and spectrophotometric detection, respectively. Repeatability (relative standard deviation, RSD) was better than 3.7% and 2.6% for conductometric and spectrophotometric detection, respectively. PMID:15537291

Lima, M J Reis; Fernandes, Sílvia M V; Rangel, António O S S



Concentrations of 17?-Estradiol in Holstein Whole Milk  

Microsoft Academic Search

Some individuals have expressed concern about es- trogens in food because of their potential to promote growth of estrogen-sensitive human cancer cells. Re- searchers have reported concentrations of estrogen in milk but few whole milk samples have been analyzed. Because estrogen associates with the fat phase of milk, the analysis of whole milk is an important consider- ation. The objectives

D. A. Pape-Zambito; A. L. Magliaro; R. S. Kensinger



Salvage of blood urea nitrogen in sheep is highly dependent on plasma urea concentration and the efficiency of capture within the digestive tract.  


The aims of this study were 1) to determine whether transfer of blood urea to the gastrointestinal tract (GIT) or the efficiency of capture of urea N within the GIT is more limiting for urea N salvage, and 2) to establish the relationship between plasma urea concentration and recycling of urea N to the GIT. We used an i.v. urea infusion model in sheep to elevate the urea entry rate and plasma concentrations, thus avoiding direct manipulation of the rumen environment that otherwise occurs when feeding additional N. Four growing sheep (28.1 +/- 0.6 kg of BW) were fed a low-protein (6.8% CP, DM basis) diet and assigned to 4 rates of i.v. urea infusion (0, 3.8, 7.5, or 11.3 g of urea N/d; 10-d periods) in a balanced 4 x 4 Latin square design. Nitrogen retention (d 6 to 9), urea kinetics([(15)N2]urea infusion over 80 h), and plasma AA were determined. Urea infusion increased apparent total tract digestibility of N (29.9 to 41.3%) and DM (47.5 to 58.9%), and N retention (1.45 to 5.46 g/d). The plasma urea N entry rate increased (5.1 to 21.8 g/d) with urea infusion, as did the amount of urea N entering the GIT (4.1 to 13.2 g/d). Urea N transfer to the GIT increased with plasma urea concentration, but the increases were smaller at greater concentrations of plasma urea. Anabolic use of urea N within the GIT also increased with urea infusion (1.43 to 2.98 g/d; P = 0.003), but anabolic use as a proportion of GIT entry was low and decreased (35 to 22%; P = 0.003) with urea infusions. Consequently, much (44 to 67%) of the urea N transferred to the GIT returned to the liver for resynthesis of urea (1.8 to 9.2 g/d; P < 0.05). The present results suggest that transfer of blood urea to the GIT is 1) highly related to blood urea concentration, and 2) less limiting for N retention than is the efficiency of capture of recycled urea N by microbes within the GIT. PMID:17202392

Sunny, N E; Owens, S L; Baldwin, R L; El-Kadi, S W; Kohn, R A; Bequette, B J



Genetic Analysis of Milk Urea Nitrogen and Lactose and Their Relationships with Other Production Traits in Canadian Holstein Cattle  

Microsoft Academic Search

The objective of this research was to estimate herita- bilities of milk urea nitrogen (MUN) and lactose in the first 3 parities and their genetic relationships with milk,fat,protein,andSCS inCanadianHolsteins.Data were a random sample of complete herds (60,645 test day records of 5,022 cows from 91 herds) extracted from the edited data set, which included 892,039 test-day records of 144,622 Holstein

F. Miglior; A. Sewalem; J. Jamrozik; J. Bohmanova; D. M. Lefebvre; R. K. Moore



Chemical composition of camel skim milk concentrated by ultrafiltration  

Microsoft Academic Search

Camel skim milk was concentrated by ultrafiltration (UF) to volume concentration ratios (VCR) of 2, 3, 4 and 5. Gross composition and mineral contents of skim milk and retentates, as well as retention and recovery of components were studied. All fat, CN, WPN, 13–18% of NPN and about 1% of lactose were retained during UF of camel skim milk. Recovery

Mohamed A. Mehaia



Effect of estradiol-17? and trenbolone acetate on growth, nitrogen retention, and urea metabolism in goat kids fed milk  

Microsoft Academic Search

Effects of 5 mg estradiol-17? plus 30 mg trenbolone acetate on growth, N retention, and urea metabolism were studied in eight control and eight male goat kids implanted at 21 days of age and hand-fed milk. N balance was measured over a 5 day period beginning 16 and 26 days (Periods 1 and 2, respectively) after treatment. There was no

Ph. Schmidely; J. Hervieu; P. Bas; A. Rouzeau



Iodine concentration in milk sampled from Canadian farms.  


A study was conducted to determine the iodine concentration in milk and the relationship between that concentration and milking and feeding management practices. Milk samples were collected from the bulk tanks of 501 farms in all provinces of Canada. With a view to obtaining further information about farm management, a questionnaire was completed at each of the selected farms. Total iodine concentration (organic and inorganic) in the milk was determined using inductively coupled plasma mass spectrometry. The farms were grouped for each of the variables and, based on significant differences in iodine concentrations, 15 variables were selected for further analysis. A general linear model was fitted, with milk iodine as the response variable to main and two-way interaction effects. The mean iodine concentration in Canadian milk was 304 ± 8.4 ?g/kg, with concentrations ranging from 54 to 1,902 ?g/kg. Analysis of the questionnaire data suggested that component feeding was associated with lower iodine levels in milk than the levels obtained with total mixed rations. Neither the use of mineral supplementation nor the form of supplementation affected iodine levels in milk. Washing and dipping the teats before milking affected iodine in milk. The method of application of the teat sanitizers appears to be important, given that spray applications (inline or hand spraying) were associated with higher levels than those observed with the dip-cup procedure. In conclusion, Canadian milk iodine concentration varies considerably and appears to be influenced by feeding and milking practices. PMID:20828472

Borucki Castro, S I; Berthiaume, R; Laffey, P; Fouquet, A; Beraldin, F; Robichaud, A; Lacasse, P



Milk qualitative and quantitative characteristics, metabolic profile and rumen pH and NH3 concentration in grazing goats fed with two types of concentrate  

Microsoft Academic Search

SUMMARY - The aim of this study was to investigate the effect of two types of concentrates characterized by different degradation (starch and nitrogen rapidly degradable (PBC) and less rapidly degradable (PMB)) compared with the group not supplemented (P) on milk quantitative and qualitative (protein, fat, lactose, urea, saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids (FAs), CLA, C18:1t,

A. Di Trana; S. Claps; G. F. Cifuni; V. Fedele; G. Impemba; P. Celi


On quantifying the dissolution behaviour of milk protein concentrate  

Microsoft Academic Search

Milk protein concentrate (MPC) is a newly developed dairy powder with wide range of applications as ingredients in the food industry, such as cheese, yogurt, and beverage. MPC has relatively poor solubility as a result of their high protein content (40–90wt%), with distinct dissolution behaviour in comparison to skim milk or whole milk powders. Here, a focused beam reflectance measurement

Y. Fang; C. Selomulya; S. Ainsworth; M. Palmer; X. D. Chen



Simplified methodology to determine breast milk retinol concentrations  

Microsoft Academic Search

The impact of a nutritional intervention trial on vitamin A status can be evaluated by measuring the total vi- tamin A concentration in breast milk both before and after the intervention. Because breast milk contains a spectrum of retinyl esters as well as retinol and high lipid content, de- termination of total breast milk retinol routinely requires saponification with alcoholic

Sherry A. Tanumihardjo; Kristina L. Penniston


Construction of a simple optical sensor based on air stable lipid film with incorporated urease for the rapid detection of urea in milk.  


This work describes the construction of a simple optical sensor for the rapid, selective and sensitive detection of urea in milk using air stable lipid films with incorporated urease. The lipid film is stabilized on a glass filter by polymerization using UV (ultra-violet) radiation prior its use. Methacrylic acid was the functional monomer, ethylene glycol dimethacrylate was the crosslinker and 2,2'-azobis-(2-methylpropionitrile) was the initiator. Urease is incorporated within this mixture prior to the polymerization. The presence of the enzyme in these films quenched this fluorescence and the colour became similar to that of the filters without the lipid films. A drop of aqueous solution of urea provided a "switching on" of the fluorescence which allows the rapid detection of this compound at the levels of 10(-8) M concentrations. The investigation of the effect of potent interferences included a wide range of compounds usually found in foods and also of proteins and lipids. These lipid membranes were used for the rapid detection of urea in milk. PMID:20708117

Nikoleli, Georgia-Paraskevi; Nikolelis, Dimitrios P; Methenitis, Constantinos



Concentrations of cadmium and lead in different types of milk  

Microsoft Academic Search

Concentrations of Pb and Cd were determined in samples of human, raw and pasteurized cow's and goat's milk and powdered infant\\u000a formula. The following mean Cd concentrations (and ranges) were recorded: in human milk, 2.70??g\\/l (0.6–11.3, n=55); in raw cow's milk, 4.88??g\\/l (0.7–23.1, n=47); in pasteurized cow's milk, 4.30??g\\/l (3.4–5.9, n=6); in goat's milk, 7.81??g\\/l (1.0–18.4, n=38); and in powdered,

E. M. Rodríguez Rodríguez; E. Delgado Uretra; C. Díaz Romero



Lactoferrin concentrations in milk from normal and subclinical mastitic cows.  


The concentrations of lactoferrin (Lf) in quarter milk from normal lactating cows and subclinical mastitic cows were measured to determine whether the Lf concentration in milk is influenced by the age of the cow, the stage of lactation, number of milk somatic cells and the presence of pathogens. Lf concentrations in 111 quarter milk samples from 28 normal lactating cows and 270 quarter milk samples from 198 subclinical mastitic cows were measured by means of a single radial immunodiffusion test. Lf concentrations (means +/- standard deviations; logarithmic form) in normal cows and subclinical mastitic cows were 2.23 +/- 0.39 and 2.70 +/- 0.39, respectively. The mean milk Lf concentration (log) in subclinical mastitic cows was significantly (p<0.01) higher than that in normal cows. The mean milk Lf concentration (log) in normal lactating cows aged 5 years was lower than those in normal lactating cows aged 2 years (p<0.01) and 3 years (p<0.05). The results showed that the milk Lf concentration (log) is associated with age of the dairy cow (one-way analysis of variance test, p<0.01). The mean milk Lf concentration (log) in the latter lactational period tended to be higher than those in the peak and middle periods. Milk Lf concentrations (log) tended to be proportional to the level of the somatic cell count (SCC) score. Mean milk Lf concentrations (log) in subclinical mastitic cows infected with Staphylococcus aureus and with other streptococci species were significantly (p<0.01) higher than those in cows infected with coagulase-negative staphylococci and with Corynebacterium bovis. PMID:12679560

Hagiwara, Sei-ichi; Kawai, Kazuhiro; Anri, Akira; Nagahata, Hajime



Effect of time duration of ruminal urea infusions on ruminal ammonia concentrations and portal-drained visceral extraction of arterial urea-N in lactating Holstein cows.  


The effects of a 6 versus 24h ruminal urea infusion in lactating dairy cows fed a basal diet deficient in N on ruminal ammonia concentration, arterial urea-N concentration, net portal-drained viscera (PDV) urea-N flux, arterial urea-N extraction across the PDV, and renal urea-N kinetics were investigated. Three Danish Holstein cows fitted with ruminal cannulas and permanent indwelling catheters in major splanchnic blood vessels were randomly allocated to a 3 × 3 Latin square design with 21-d periods. Treatments were ventral ruminal infusion of water for 24h (water INF), 24-h infusion of 15 g of urea/kg of dry matter intake (DMI; 24-h INF), and 6-h infusion of 15 g of urea/kg of DMI (6-h INF). The 6-h INF was initiated 0.5h after the afternoon feeding, and ran until 2230 h. Eight sample sets of arterial, portal, and hepatic blood, ruminal fluid, and urine were obtained at 0.5h before the morning feeding and 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, and 6.5h after feeding (i.e., 9 to 15.5h after the 6h infusion was terminated). A substantial decrease in DMI for 6-h INF compared with 24-h INF and water INF was observed, and it has to be recognized that DMI may have confounding effects. However, the experimental setting plan was met (i.e., to cause changes in the daily pattern of ruminal ammonia and blood urea-N concentrations). The arterial urea-N concentration for 24-h INF and 6-h INF were greater than the arterial urea-N concentration with water INF throughout the sampling window. However, the arterial urea-N concentration for 6-h INF decreased steadily with sampling time reflecting a carryover effect from the ruminal urea infusion. The ruminal ammonia concentration and net portal flux of ammonia for 6-h INF were not different from water INF; hence, no carryover effect on ruminal ammonia concentration was observed. The portal flux of urea-N was not affected by treatment (i.e., even the combination of low ruminal ammonia and high arterial urea-N concentration with 6-h INF was not used by the cow to increase the uptake of urea-N across the PDV). Arterial urea-N extraction across the PDV was increased with water INF especially from 0.5 to 3.5h postprandial relative to the urea infusion treatments, reflecting increased epithelial permeability for urea-N. This indicates that daily ruminal peak of ammonia or blood urea-N concentrations overruled potential signals from low ruminal ammonia concentration observed during the sampling window. In conclusion, dairy cows appear unable to increase transport of urea-N from blood to gut in periods with low ruminal ammonia concentrations, even in a situation with infrequent N supply and apparent carryover effects on blood urea-N. It is speculated that mechanisms responsible for downregulation of epithelial urea-N transport based on daily maximum concentrations of ammonia in the rumen or urea-N in the blood suppresses any short-term signal from low ruminal ammonia during periods with low ruminal N supply. PMID:22365222

Rřjen, B A; Kristensen, N B



Urea for Lactating Dairy Cattle. III. Nutritive Value of Rations of Corn Silage Plus Concentrate Containing Various Levels of Urea[1] and [2  

Microsoft Academic Search

Four mature Holstein cows were used simultaneously in a 4 X 4 Latin-square design (balanced for residual effects) to evaluate rations containing various pro- portions of concentrate urea. Corn silage was fed ad libitnm as the sole forage. All concentrates were isocalo,rie and isoni- trogenous, each containing the same amounts of every ingredient except soybean oil meal, urea, and hominy.

J. B. Holter; N. F. Colovos; H. A. Davis; W. E. Urban Jr.



Adaptation of Lactating Cows to Rations Containing Urea  

Microsoft Academic Search

Effects of a progressive change in 6 wk from a urea-free concentrate to one providing .34 (medium) or .66 g (high) urea\\/kg body weight on jugular blood composition and animal performance were studied with 27 cows. Consumption of dry matter was not affected even at the high rate of urea intake. Milk produc- tion was maximum when after 6 wk

P. R. Narasimhalu; R. J. Belzile; G. J. Brisson; W. B. Holtman



Docosahexaenoic and arachidonic acid concentrations in human breast milk worldwide.  


Concentrations of the long-chain polyunsaturated fatty acids (LCPUFAs) docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) in human breast milk are important indicators of infant formula DHA and AA concentrations, and recent evidence suggests that neural maturation of breastfed infants is linked to breast-milk LCPUFA concentrations. We report a descriptive meta-analysis that considered 106 studies of human breast milk culled to include only studies that used modern analysis methods capable of making accurate estimates of fatty acid (FA) profiles and criteria related to the completeness of reporting. The final analysis included 65 studies of 2474 women. The mean (+/-SD) concentration of DHA in breast milk (by wt) is 0.32 +/- 0.22% (range: 0.06-1.4%) and that of AA is 0.47 +/- 0.13% (range: 0.24-1.0%), which indicates that the DHA concentration in breast milk is lower than and more variable than that of AA. The highest DHA concentrations were primarily in coastal populations and were associated with marine food consumption. The correlation between breast-milk DHA and AA concentrations was significant but low (r = 0.25, P = 0.02), which indicates that the mean ratio of DHA to AA in regional breast milk varies widely. This comprehensive analysis of breast-milk DHA and AA indicates a broad range of these nutrients worldwide and serves as a guide for infant feeding. PMID:17556680

Brenna, J Thomas; Varamini, Behzad; Jensen, Robert G; Diersen-Schade, Deborah A; Boettcher, Julia A; Arterburn, Linda M



Adaptive network based on fuzzy inference system for equilibrated urea concentration prediction.  


Post-dialysis urea rebound (PDUR) has been attributed mostly to redistribution of urea from different compartments, which is determined by variations in regional blood flows and transcellular urea mass transfer coefficients. PDUR occurs after 30-90min of short or standard hemodialysis (HD) sessions and after 60min in long 8-h HD sessions, which is inconvenient. This paper presents adaptive network based on fuzzy inference system (ANFIS) for predicting intradialytic (Cint) and post-dialysis urea concentrations (Cpost) in order to predict the equilibrated (Ceq) urea concentrations without any blood sampling from dialysis patients. The accuracy of the developed system was prospectively compared with other traditional methods for predicting equilibrated urea (Ceq), post dialysis urea rebound (PDUR) and equilibrated dialysis dose (eKt/V). This comparison is done based on root mean squares error (RMSE), normalized mean square error (NRMSE), and mean absolute percentage error (MAPE). The ANFIS predictor for Ceq achieved mean RMSE values of 0.3654 and 0.4920 for training and testing, respectively. The statistical analysis demonstrated that there is no statistically significant difference found between the predicted and the measured values. The percentage of MAE and RMSE for testing phase is 0.63% and 0.96%, respectively. PMID:23806679

Azar, Ahmad Taher



Effect of Mastitis on Milk Perchlorate Concentrations in Dairy Cows  

Microsoft Academic Search

Recentsurveyshaveidentifiedthepresenceofperchlo- rate, a natural compound and environmental contami- nant, in forages and dairy milk. The ingestion of perchlo- rate is of concern because of its ability to competitively inhibit iodide uptake by the thyroid and to impair syn- thesis of thyroid hormones. A recent study established that milk perchlorate concentrations in cattle highly cor- relate with perchlorate intake. However, there

D. D. Bannerman; M. J. Paape; R. L. Baldwin VI; C. P. Rice; K. Bialek; A. V. Capuco



Conjugated linoleic acid concentrations of human milk and infant formula  

Microsoft Academic Search

Conjugated linoleic acid (CLA) is an anticarcinogen found in ruminant products. CLA may also act as a growth promotor in the neonate. Because of the potential importance of CLA to maternal and infant health, CLA concentration was quantified in human milk and infant formula. Human milk samples (n = 14) were collected by complete breast expression, and four brands of

Michelle K. McGuire; Yongsoon Park; Rebecca A. Behre; Lisa Y. Harrison; Terry D. Shultz; Mark A. McGuire



Genetic relationship between milk urea nitrogen and reproductive performance in Holstein dairy cows.  


The objective of this study was to describe the genetic and phenotypic relationship between milk urea nitrogen (MUN) and reproductive traits in Iranian Holstein dairy cows. Test-day MUN data obtained from 57 301 dairy cows on 20 large dairy herds in Iran between January 2005 and June 2009. Genetic parameters for MUN and reproductive traits were estimated with a five-trait model using ASREML program. Random regression test-day models were used to estimate heritabilities separately for MUN from first, second and third lactations. Regression curves were modeled using Legendre polynomials of order 3. Herd-year-season along with age at calving was included as fixed effects in all models for reproductive traits. Heritabilities for MUN and reproductive traits were estimated separately for first lactation, second lactation and third lactation. The estimated heritabilities for MUN varied from 0.18 to 0.22. The heritability estimate was low for reproductive traits, which ranged from 0.02 to 0.06 for different traits and across parities. Except for days open, phenotypic and genetic correlations of MUN with reproductive performance traits were close to zero. Genetic correlations between MUN and days open were 0.23, 0.35 and 0.45 in first, second and third lactation, respectively. However, the phenotypic correlation between MUN at different parities was moderate (0.28 to 0.35), but the genetic correlation between MUN at different parities was high and ranged from 0.84 to 0.97. This study shows a limited application of MUN for use in selection programs to improve reproductive performance. PMID:22440698

Ghavi Hossein-Zadeh, Navid; Ardalan, Mehrnaz



Milk concentrations of flupenthixol, nortriptyline and zuclopenthixol and between-breast differences in two patients  

Microsoft Academic Search

Flupenthixol (FP), nortriptyline (NT) and zuclopenthixol, (ZCP) were determined in breast milk and plasma from 2 puerperal, lactating women with psychiatric disorders. The milk concentrations were equal to, higher and lower than those in plasma for FP, NT and ZCP, respectively. Variation in milk triglyceride concentration, but not milk pH, could partly explain between-breast differences in the milk concentrations. The

I. Matheson; J. Skjaeraasen



Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows.  


Forty lactating Holstein cows, including 10 with ruminal cannulas, were blocked by days in milk into 8 groups and then randomly assigned to 1 of 8 incomplete 5 x 5 Latin squares to assess the effects of 5 levels of dietary crude protein (CP) on milk production and N use. Diets contained 25% alfalfa silage, 25% corn silage, and 50% concentrate, on a dry matter (DM) basis. Rolled high-moisture shelled corn was replaced with solvent-extracted soybean meal to increase CP from 13.5 to 15.0, 16.5, 17.9, and 19.4% of DM. Each of the 4 experimental periods lasted 28 d, with 14 d for adaptation and 14 d for data collection. Spot sampling of ruminal digesta, blood, urine, and feces was conducted on d 21 of each period. Intake of DM was not affected by diet but milk fat content as well as ruminal acetate, NH3, and branched-chain volatile fatty acids, urinary allantoin, and blood and milk urea all increased linearly with increasing CP. Milk and protein yield showed trends for quadratic responses to dietary CP and were, respectively, 38.3 and 1.18 kg/d at 16.5% CP. As a proportion of N intake, urinary N excretion increased from 23.8 to 36.2%, whereas N secreted in milk decreased from 36.5 to 25.4%, as dietary protein increased from 13.5 to 19.4%. Under the conditions of this study, yield of milk and protein were not increased by feeding more than 16.5% CP. The linear increase in urinary N excretion resulted from a sharp decline in N efficiency as dietary CP content increased. PMID:16606741

Colmenero, J J Olmos; Broderick, G A



Plasma urea, creatinine and uric acid concentrations in relation to feeding in peregrine falcons (Falco peregrinus)  

Microsoft Academic Search

Significant post?prandial increases in plasma uric acid and plasma urea concentrations were observed in peregrine falcons. Post?prandial uric acid concentrations were similar to those in birds suffering from hyperuricaemia and gout and were well above the theoretical limit of solubility of sodium urate in plasma. It is not clear why under normal circumstances no urate deposits occur in peregrine falcons

J. T. Lumeij; J. D. Remple



Short communication: effects of supplementation with pomegranate seed pulp on concentrations of conjugated linoleic acid and punicic acid in goat milk.  


The effects of feeding pomegranate seed pulp (PSP) on milk yield, milk composition, fatty acid profiles of milk fat, and blood metabolites were examined in this study. During a pretrial period, 27 multiparous southern Khorasan (Iran) cross-bred goats were fed a similar diet and dry matter intake, milk yield, and milk composition were recorded. After adaptation and based on pretrial records, the goats were randomly assigned to 1 of 3 experimental diets and were housed in individual stalls. Experimental diets included 0, 6, or 12% of PSP (dry matter basis) and were fed as total mixed rations ad libitum for a 45-d period. Diets were formulated to be isonitrogenous and isocaloric. Supplementation of PSP did not affect dry matter intake or average daily gain of goats. Milk yield was not affected by inclusion of PSP in the diet. Milk fat concentration of goats fed diets with 6 and 12% PSP increased, but milk fat yield, milk protein concentration, and milk solids-not-fat concentration of goats were not affected by diets. Feeding PSP did not affect blood glucose, cholesterol, urea N, triglyceride, or lipoproteins. Feeding goats a diet containing 12% PSP modified the milk fatty acid profile, including conjugated linoleic, punicic, and vaccenic acids. PMID:21787942

Modaresi, J; Fathi Nasri, M H; Rashidi, L; Dayani, O; Kebreab, E



Effects of supplementary concentrate composition on milk yield, milk composition and pasture utilization of rotationally grazed dairy cows  

Microsoft Academic Search

Twenty eight lactating cows were used in a randomized block design experiment to evaluate the effects of supplementary nitrogen source and heat treatment of rapessed meal containing concentrate compound on pasture utilization under a controlled rotational grazing system. The four supplemental concentrates were: 1) a cereal by-product based basic dairy concentrate (BDC); 2) BDC with 0.9% additional urea (UREA); 3)

Alem Tsehai Tesfa; Perttu Virkajärvi; Mikko Tuori; Liisa Syrjälä-Qvist



Effect of the presence of a urea fertilizer plant on the nitrate content of berseem and constituents of milk and blood of buffaloes.  


An attempt was made to study the effect of the presence of "El-Nasr" Fertilizer Plant in "Talkha" on the nitrate content of berseem as well as on some blood and milk constituents of buffaloes raised in the surrounding areas of the factory. The studied areas included the northern area (0-2 km from the factory), the south eastern area (1.5-3 km from the factory) and the control area (not nearer than 5 km from the factory). The study showed that the nitrate content in berseem grown near the factory had higher NO3 values exceeding 2% NO3 in DM in some cases. Berseem from the areas far from the factory had lower NO3 levels (about 50-200 ppm NO3 in DM). Samples from "El-Mansoura" and "El-Manzala" contained higher NO3 levels than the samples from "El-Senblawin" and "Belkas." There were no clear effects of cut sequence on nitrate levels in berseem. Values of blood packed cell volume and methaemoglobin percentages and plasma urea concentration did not differ significantly among the three areas (northern, south eastern and control areas). Blood haemoglobin and total protein contents were lower, whereas transaminase activity and blood nitrate contents were higher in buffaloes of the south eastern area than those for animals of the other two areas. The blood ammonia content in the control buffaloes was higher than that of the animals of the northern and south eastern areas. The analysis of milk revealed that nitrate levels were not different among areas or between morning and evening milkings. Total milk protein was higher in the northern area.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2548453

el-Ayoty, S A; Abdelhamid, A M


Genetic analysis of milk urea nitrogen and lactose and their relationships with other production traits in Canadian Holstein cattle.  


The objective of this research was to estimate heritabilities of milk urea nitrogen (MUN) and lactose in the first 3 parities and their genetic relationships with milk, fat, protein, and SCS in Canadian Holsteins. Data were a random sample of complete herds (60,645 test day records of 5,022 cows from 91 herds) extracted from the edited data set, which included 892,039 test-day records of 144,622 Holstein cows from 4,570 herds. A test-day animal model with multiple-trait random regression and the Gibbs sampling method were used for parameter estimation. Regression curves were modeled using Legendre polynomials of order 4. A total of 6 separate 4-trait analyses, which included MUN, lactose, or both (yield or percentage) with different combinations of production traits (milk, fat and protein yield, fat and protein percentages, and somatic cell score) were performed. Average daily heritabilities were moderately high for MUN (from 0.384 to 0.414), lactose kilograms (from 0.466 to 0.539), and lactose percentage (from 0.478 to 0.508). Lactose yield was highly correlated with milk yield (0.979). Lactose percentage and MUN were not genetically correlated with milk yield. However, lactose percentage was significantly correlated with somatic cell score (-0.202). The MUN was correlated with fat (0.425) and protein percentages (0.20). Genetic correlations among parities were high for MUN, lactose percentage, and yield. Estimated breeding values (EBV) of bulls for MUN were correlated with fat percentage EBV (0.287) and EBV of lactose percentage were correlated with lactation persistency EBV (0.329). Correlations between lactose percentage and MUN with fertility traits were close to zero, thus diminishing the potential of using those traits as possible indicators of fertility. PMID:17430951

Miglior, F; Sewalem, A; Jamrozik, J; Bohmanova, J; Lefebvre, D M; Moore, R K



Extracellular urea concentration modulates cAMP production in the mouse MTAL  

Microsoft Academic Search

Extracellular urea concentration modulates cAMP production in the mouse MTAL. Ionic reabsorption along the ascending limb of Henle's loop (TAL) is controlled by hormonal stimulation. Most of the hormones that affect this reabsorption regulate ionic transporter activity via cAMP, and some of these hormonal actions have been shown to be modulated by interstitial osmolarity. We studied the early effects of

Maryvonne Baudouin-Legros; Lahoussaine Asdram; Danielle Tondelier; Marc Paulais; Takis Anagnostopoulos



Production performance and milk composition of dairy cows fed different concentrations of flax hulls  

Microsoft Academic Search

A total of 45 lactating Holstein cows averaging 617kg of body weight (SE=20.6) were allotted at week 20 of lactation to five groups of nine cows blocked for similar days in milk to determine the effects of feeding different concentrations of flax hulls on dry matter (DM) intake, milk production, milk composition, digestion, and milk concentration of the mammalian lignan

H. V. Petit; N. Gagnon



Alkaline Phosphatase Activity and Pyridoxal Phosphate Concentrations in the Milk of Various Species1-2  

Microsoft Academic Search

Because pyridoxal phosphate does not normally cross membranes, it was intriguing that the concentration of pyridoxalphosphate is much higher in goat milk than in human milk. We also noted that, al though the total vitamin B-6 concentration of bovine milk was similar to that of caprine milk, the bovinemilk had lower pyridoxal phosphate. Preliminary data from five Alpinegoats, five BrownSwiss



Chemical Alterations of Heat Treated Concentrated Skim Milk  

Microsoft Academic Search

Heat induced production of 5-Hydro- xymethylfurfural and of the protein- bound pigments (melanoidines) in con- centrated skim milk was studied. Under normal commercial sterilization condi- tions (F < 5), 5-Hydroxymethylfurfural concentration increased sharply with the heat intensity. Above F = 5, (overheat- ing), slightly additional amounts were produced. In contrast, the amount of protein-bound pigments increased at a constant rate

M. Groux



Functional Fish Protein Concentrate in Milk Replacers for Calves  

Microsoft Academic Search

A fish protein concentrate with im- proved function properties (i.e. water- holding and emulsification capacity) has been tested in milk replacers for calves as the principal source of protein in a semisynthetic diet and with dried whey in a practical diet. The fish protein concen- trate did not cause digestive problems, and the calves remained entirely healthy when fed the

J. Opstvedt; G. Sřbstad; P. Hansen




Microsoft Academic Search

Two experiments were carried out to determine the effect on rate of growth and conversion of different levels of a protein supplement, with or without maize grain in basal diets of sugarcane\\/urea or sugar cane and molasses\\/urea given in separately feeders. In experiment 1 the levels of a 30% protein concentrate (compounded from soya bean, meat, maize gluten and alfalfa)

R Silvestre; N A MacLeod; T R Preston


Polyunsaturated Fatty Acid Concentrates of Carp Oil: Chemical Hydrolysis and Urea Complexation  

Microsoft Academic Search

The aims of this study were to compare three treatments in the chemical hydrolysis reaction of bleached oil from carp (Cyprinus carpio) heads and to obtain polyunsaturated fatty acid concentrates by urea complexation. The three treatments were carried out\\u000a with different oil:ethanol molar ratios. In the treatment with a 1:39 molar ratio, a higher yield of free fatty acids was

Valéria T. Crexi; Micheli L. Monte; Maurício L. Monte; Luiz A. A. Pinto


Concentration of eicosapentaenoic acid and docosahexaenoic acid from fish oil by hydrolysis and urea complexation  

Microsoft Academic Search

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) derived from chemically or enzymatically hydrolyzed from sardine oil were concentrated by urea complexation. The enzymatic hydrolysis was effected in aqueous emulsion using five commercial lipases from Pseudomonas, three immobilized (PS-CI, PS-CII and PS-DI) and two soluble lipases (AK-20 and PS-30). EPA and DHA were determined by gas–liquid chromatography as methyl esters. Results

N Gámez-Meza; J. A Noriega-Rodr??guez; L. A Medina-Juárez; J Ortega-Garc??a; J Monroy-Rivera; F. J Toro-Vázquez; H. S Garc??a; O Angulo-Guerrero



Triazolothienopyrimidine Inhibitors of Urea Transporter UT-B Reduce Urine Concentration  

PubMed Central

Urea transport (UT) proteins facilitate the concentration of urine by the kidney, suggesting that inhibition of these proteins could have therapeutic use as a diuretic strategy. We screened 100,000 compounds for UT-B inhibition using an optical assay based on the hypotonic lysis of acetamide-loaded mouse erythrocytes. We identified a class of triazolothienopyrimidine UT-B inhibitors; the most potent compound, UTBinh-14, fully and reversibly inhibited urea transport with IC50 values of 10 nM and 25 nM for human and mouse UT-B, respectively. UTBinh-14 competed with urea binding at an intracellular site on the UT-B protein. UTBinh-14 exhibited low toxicity and high selectivity for UT-B over UT-A isoforms. After intraperitoneal administration of UTBinh-14 in mice to achieve predicted therapeutic concentrations in the kidney, urine osmolality after administration of 1-deamino-8-D-arginine-vasopressin was approximately 700 mosm/kg H2O lower in UTBinh-14–treated mice than vehicle-treated mice. UTBinh-14 also increased urine output and reduced urine osmolality in mice given free access to water. UTBinh-14 did not reduce urine osmolality in UT-B knockout mice. In summary, these data provide proof of concept for the potential utility of UT inhibitors to reduce urinary concentration in high-vasopressin, fluid-retaining conditions. The diuretic mechanism of UT inhibitors may complement the action of conventional diuretics, which target sodium transport.

Yao, Chenjuan; Anderson, Marc O.; Zhang, Jicheng; Yang, Baoxue; Phuan, Puay-Wah



Assay of ghrelin concentration in infant formulas and breast milk  

PubMed Central

AIM: To test if total ghrelin is present in infant formulas. METHODS: Using a radioimmunoassay, we measured total ghrelin concentrations in 19 samples of commercial infant formulas and in 20 samples of human milk. We also determined ghrelin concentration in the serum of infants and lactating mothers. RESULTS: Ghrelin concentrations were significantly higher in artificial milk (2007.1 ± 1725.36 pg/mL) than in human milk (828.17 ± 323.32 pg/mL) (P = 0.005). The mean ghrelin concentration in infant serum (n = 56) was 1115.86 ± 42.89 pg/mL, and was significantly higher (P = 0.023) in formula-fed infants (1247.93 ± 328.07 pg/mL) than in breast-fed infants (1045.7 ± 263.38 pg/mL). The mean serum ghrelin concentration (mean ± SD) in lactating mothers (n = 20) was 1319.18 ± 140.18 pg/mL. CONCLUSION: This study provides evidence that total ghrelin is present in infant formulas. This finding raises diverse questions regarding the uptake, absorption and metabolic effects of this hormone.

Savino, Francesco; Petrucci, Elisa; Lupica, Maria Maddalena; Nanni, Giuliana Eva; Oggero, Roberto



Assessment of isoflavonoid concentrations in Australian bovine milk samples.  


There is considerable interest in the possibility that diet-derived isoflavonoids may help in protection against a number of chronic diseases common in Western society. Based on animal studies, however, concerns have been raised that consumption of isoflavonoids by infants and young children may be undesirable. Clover contains isoflavonoids and therefore may represent, via milk, a source of isoflavonoids in the human diet. In this study the concentrations of daidzein (7, 4'-dihydroxyisoflavone), genistein (5, 7, 4'-trihydroxyisoflavone) and equol (7-hydroxy-(4'-hydroxyphenyl)chroman) were measured using HPLC in cows' milk samples obtained from 76 farms in three Australian states. In addition, concentrations were measured in samples collected from one South Australian factory both before and after pasteurization. Concentrations in all samples were found to be extremely low. The mean daidzein concentration was < 5 ng/ml. Mean genistein concentrations ranged from just detectable (approximately 2 ng/ml) in Victorian samples collected during summer to 20-30 ng/ml in samples from all states collected during spring when isoflavonoid-containing clover is most dominant in pasture. Mean equol concentrations ranged from 45 +/- 10 ng/ml in Victorian farm samples collected during summer to 293 +/- 52 ng/ml in Western Australian samples collected in spring. The mean concentrations of genistein and equol in post-pasteurization samples collected in spring were approximately double those for samples collected in autumn. Pasteurization had no effect on isoflavonoid concentrations. We conclude that the concentrations of isoflavonoids in Australian cows' milk are low and are therefore unlikely to have any pronounced biological effects in human consumers. PMID:9718497

King, R A; Mano, M M; Head, R J



Major advances in concentrated and dry milk products, cheese, and milk fat-based spreads.  


Advances in dairy foods and dairy foods processing since 1981 have influenced consumers and processors of dairy products. Consumer benefits include dairy products with enhanced nutrition and product functionality for specific applications. Processors convert raw milk to finished product with improved efficiencies and have developed processing technologies to improve traditional products and to introduce new products for expanding the dairy foods market. Membrane processing evolved from a laboratory technique to a major industrial process for milk and whey processing. Ultra-filtration and reverse osmosis have been used extensively in fractionation of milk and whey components. Advances in cheese manufacturing methods have included mechanization of the making process. Membrane processing has allowed uniform composition of the cheese milk and starter cultures have become more predictable. Cheese vats have become larger and enclosed as well as computer controlled. Researchers have learned to control many of the functional properties of cheese by understanding the role of fat and calcium distribution, as bound or unbound, in the cheese matrix. Processed cheese (cheese, foods, spreads, and products) maintain their importance in the industry as many product types can be produced to meet market needs and provide stable products for an extended shelf life. Cheese delivers concentrated nutrients of milk and bio-active peptides to consumers. The technologies for the production of concentrated and dried milk and whey products have not changed greatly in the last 25 yr. The size and efficiencies of the equipment have increased. Use of reverse osmosis in place of vacuum condensing has been proposed. Modifying the fatty acid composition of milkfat to alter the nutritional and functional properties of dairy spread has been a focus of research in the last 2 decades. Conjugated linoleic acid, which can be increased in milkfat by alteration of the cow's diet, has been reported to have anticancer, anti-atherogenic, antidiabetic, and antiobesity effects for human health. Separating milk fat into fractions has been accomplished to provide specific fractions to improve butter spreadability, modulate chocolate meltability, and provide texture for low-fat cheeses. PMID:16537951

Henning, D R; Baer, R J; Hassan, A N; Dave, R



The effects of a probiotic on blood urea nitrogen and creatinine concentrations in large felids.  


Chronic kidney disease is a common finding in older captive exotic felids. The purpose of this study was to evaluate the effectiveness of a probiotic to reduce blood urea nitrogen and creatinine in large felids. Fifteen adult, large felids (6 tigers [Panthera tigris], 5 lions [Panthera leo], 3 cougars [Puma concolor], and 1 leopard [Panthera pardus]) were administered a probiotic twice daily after a baseline complete blood cell count and plasma chemistry panel was obtained. Plasma chemistry values were rechecked at 2 mo (n = 14) and 6 mo (n = 9). There was no significant change in blood urea nitrogen over time; however, there was a significant change in creatinine over time (P = 0.04). Creatinine concentration decreased significantly between 2 and 6 mo (P = 0.02), and a decrease was seen between 0 and 6 mo, but this change was not significant (P = 0.05). There was no significant difference noted for creatinine concentration between 0 and 2 mo (P = 0.35). This probiotic may be helpful in large felids with elevated creatinine concentrations because of chronic kidney disease; however, further studies are warranted. PMID:22950314

McCain, Stephanie; Allender, Matthew C; Schumacher, Juergen; Ramsay, Edward



Breast milk lead concentrations of mothers living near tin smelters.  


We compared Pb concentration in human milk from 37 mothers living in a neighborhood of tin-ore smelters to that from 45 mothers living in a fishing community. The median breast-milk-Pb (BM-Pb) concentration was significantly (p = 0.0000001) higher (11.3 ?g L(-1); ?0.96-29.4 ?g L(-1)) in mothers living in the vicinity of smelters than that of rural mothers (1.9 ?g L(-1); ?0.96-20.0 ?g L(-1)). These mothers also showed a statistically significant correlation between length of residence and BM-Pb concentration (Spearman r = 0.6864; p < 0.0001). The estimated median exposure (for infants <6 months) was 3.0 ?g kg(-1) b.w. for rural infants compared to 7.5 ?g kg(-1) b.w. for infants in the vicinity of metal smelters. Overall, most BM-Pb concentrations (79 %) in the metal smelter area were above the critical limit of 5.0 ?g L(-1) set by the WHO. PMID:24068462

Marques, Rejane C; Moreira, Maria de Fátima R; Bernardi, José Vicente E; Dórea, José G



Colostrum, Whole Milk, and Whole Milk plus Whey Protein Concentrate for Holstein Calves[1] and [2  

Microsoft Academic Search

Thirty-six Holstein calves were fed 3.6 kg of one of three liquid diets once daily from birth until weaning at 4 wk. Diets were: (1) colostrum (collected for five milkings postpartum and frozen), (2) whole milk, and (3) whole milk plus sufficient whey proteinconcentrate to bring diets 1 and 3 to similar whey pro- tein. Compared to whole milk, colostrum

L. D. Muller; M. J. Owens; G. L. Beardsley; D. J. Schingoethe



Optimal concentrations of lysine, methionine, and threonine in milk replacers for calves less than five weeks of age.  


The AA requirements of herd-replacement calves less than 5 wk old and fed milk replacers are not clearly defined and have been estimated in a limited number of studies using milk-fed calves ranging from 5 to 20 wk of age. The objective of these 4 studies was to investigate the effect of supplementing milk replacers containing 24 to 28% crude protein (CP; from milk sources) and 17% fat with Lys, Met, and Thr to estimate the optimum requirements for calves less than 5 wk of age. Holstein bull calves (initially 3 and 4 d old, 43 +/- 1 kg of body weight, BW) were fed an 18% CP (as-fed) starter ad libitum and weaned at 31 to 32 d of age (28-d studies). Calves were housed in an unheated, curtain-sided nursery. In study 1, 6 milk replacer treatments were fed based on the combination of 3 CP concentrations (24, 26, and 28% CP) each with or without added Lys and Met. In studies 2 and 3, 26% CP and 2.34% Lys milk replacer treatments were fed to test the concentration of Met (0.64, 0.68, and 0.72% Met in study 2 and 0.64, 0.72, and 0.80% Met in study 3). In study 4, 26% CP, 2.34% Lys, and 0.72% Met milk replacer treatments were fed to test the concentration of Thr (1.06, 1.43, and 1.80%). There was a 17% improvement in average daily gain (ADG) in study 1 from adding Lys and Met that was maximized with 2.34% Lys. The ADG response to added Met in studies 2 (linear) and 3 (quadratic) were 13 and 7%, respectively, with a plateau at 0.72% Met. There was no ADG or efficiency response to added Thr in study 4. Formulating 17% fat, whey-based milk replacers fed at 0.68 kg/d to 26% CP, 2.34% Lys, and 0.72% Met appeared optimum based on responses of body weight gain, feed efficiency, and serum concentrations of urea nitrogen, while feeding calves more CP and essential AA did not improved ADG and efficiency. Requirements for calves less than 5 wk old, averaging 48 kg of BW, consuming 204 g of CP/d, and gaining 0.46 kg of BW/d, appeared to be met with 17 g of Lys, 0.31 Met:Lys ratio, 0.54 Met+Cys:Lys ratio, and a Thr:Lys ratio less than 0.60. PMID:18487666

Hill, T M; Bateman, H G; Aldrich, J M; Schlotterbeck, R L; Tanan, K G



Dexamethasone Concentrations in Bovine Blood Plasma and Milk After Intravenous Injection  

Microsoft Academic Search

Passage of dexamethasone from plasma to milk in five lactating dairy cows after an intravenous injection was evaluated by a high performance liquid chromato- graphic technique for measurement of concentrations in blood plasma and milk. The dexamethasone ester was 21-iso- nicotinate as a solution and was ad- ministered at .1 mg\\/kg bodyweight. The drug was detected in milk postinjection from

D. Tainturier; M. Alvinerie; R. A. Brandon; P. L. Toutain



Manufacture and composition of low fat Cheddar cheese from milk enriched with different protein concentrate powders  

Microsoft Academic Search

The effects of milk enriched at 3%, 4%, 5% or 6% casein with a diafiltered microfiltered retentate (DMF) powder compared with a commercial calcium caseinate (CaCN) powder and an ultrafiltered retentate (UF) powder on the production, composition and yields of low fat Cheddar cheeses were determined. The concentration of all components of milk increased in enriched milks, in wheys and

Daniel St-Gelais; Denis Roy; Pascal Audet



Effects of intrajugular glucose infusion on feed intake, milk yield, and metabolic responses of early postpartum cows fed diets varying in protein and starch concentration.  


Effects of glucose infusion on feed intake, milk production, and metabolic responses of early postpartum cows fed diets varying in starch and protein concentration were evaluated by utilizing a randomized complete block design with a 2×2 factorial arrangement of treatments. Twenty-four multiparous Holstein cows were blocked by body condition score and 305-d mature-equivalent milk yield and randomly assigned at calving to 1 of 4 treatments. Treatments were continuous intrajugular infusion of glucose (GI) or isotonic saline (SI), and diets containing high starch, low crude protein (HSLP) or high crude protein, low starch (HPLS) concentrations. Treatments were initiated at the first scheduled feeding following parturition and lasted 12d. The GI reduced cumulative dry matter intake and tended to reduce daily dry matter intake and meal size for HPLS but not HSLP compared with SI. The GI increased cumulative milk yield by 39kg/12d compared with SI by increasing it for HSLP but not HPLS. The HPLS treatment tended to increase loss of body condition from 0.65 to 0.82 body condition score units/12d compared with HSLP. Consistent with this, HPLS increased plasma concentrations of nonesterified fatty acids, ?-hydroxybutyrate, liver triglyceride, milk fat concentration and yield, 3.5% fat-corrected milk, and milk urea nitrogen compared with HSLP. Overall, the GI-HPLS treatment reduced feed intake by reducing meal size. The GI-HPLS may have reduced meal size by the independent or additive effects of (1) decreasing hepatic gluconeogenesis and promoting oxidation of acetyl coenzyme A (CoA), (2) elevated plasma nonesterified fatty acids from HPLS increasing the pool of acetyl CoA available to be oxidized, and (3) the HPLS diet increasing urea synthesis, which also provides the tricarboxylic acid cycle intermediate fumarate to promote oxidation of acetyl CoA. PMID:24011946

Brown, W E; Allen, M S



Effect of Concentrate Feed Level in Late Gestation on Subsequent Milk Yield, Milk Composition, and Fertility of Dairy Cows  

Microsoft Academic Search

ABSTRACT The effects of level of concentrate,feeding in late ges- tation on feed intake, milk yield, milk composition, and fertility in the subsequent,lactation were,evaluated,in a randomized,block design experiment,involving,60 cows. Grass silage was,offered ad libitum,for the last 28 d of gestation,either as the sole diet (0C) or supplemented with 5 kg\\/d of concentrates (5C). Following calving, the cows were offered the

T. W. J. Keady; C. S. Mayne; D. A. Fitzpatrick; M. A. McCoy



Concentration of the mammalian lignans enterolactone and enterodiol in milk of cows fed diets containing different concentrations of whole flaxseed.  


A total of 32 lactating Holstein cows with mean body weight of 622 kg (s.e. = 24) were allotted, at week 25 of lactation, to eight groups of four cows blocked for similar days in milk. The objective of the experiment was to determine the effect of feeding four dietary concentrations (0, 50, 100 or 150 g/kg of dry matter) of whole flaxseed, which contains the plant lignan precursor secoisolariciresinol diglucoside (SDG), on concentrations of two mammalian lignans (enterodiol and enterolactone) in milk. The effects of the four diets on feed intake, milk production, milk composition and digestion were also studied. Cows within each block were assigned to one of the four isonitrogenous and isoenergetic total mixed diets and the experiment was carried out from week 25 to 29 of lactation. Diets were fed for ad libitum intake. Enterolactone was the mammalian lignan, of the two metabolites studied, detected in the milk of cows and its concentration in milk tended (P = 0.08) to increase linearly with higher intake of SDG in the diet. Feed intake, milk yield and milk composition were similar among diets. Milk fatty acid profile was slightly improved by feeding flaxseed, as shown by higher concentrations of fatty acids (e.g. n-3) recognized as being beneficial for human health. Those results suggest that feeding of whole flaxseed may result in changes in milk fatty acid composition and enterolactone content, which offer benefits for consumers. PMID:22444937

Petit, H V; Gagnon, N



Copper, lead and zinc concentrations of human breast milk as affected by maternal dietary practices  

SciTech Connect

Maternal dietary practices have been found to affect the concentrations of some nutrients in human breast milk. Lead toxicity is a concern in young children. Lead, copper and zinc are thought to compete for intestinal absorption sites. The objective of the current project was to compare copper, lead and zinc contents of breast milk from practicing lacto-vegetarian and omnivore, lactating women at approximately four months post-partum. Analyses were done by atomic absorption spectrophotometry using a carbon rod attachment. Copper concentrations were higher in milk samples from lacto-ovo-vegetarians. Milk samples from the omnivores had the highest lead and zinc concentrations. Lead and copper concentrations in milk were negatively correlated. The higher zinc concentrations in the milk of the omnivore women may have been related to better utilization of zinc from meat than from plant food sources.

Umoren, J.; Kies, C.



Role of sodium and urea in the renal concentrating mechanism in Psammomys obesus  

Microsoft Academic Search

Micropunctures were performed at the tip of Henle's loops and vasa recta accessible at the extrarenal surface of the papilla in a desert rodent (Psammomys obesus) studied under mild NaCl (NaCl 4%, 0.0375 ml\\/min) and mild urea (urea 4%, 0.0375 ml\\/min) loading conditions.

M. Imbert; C. de Rouffignac; P. Philippe; S. Deiss



Influence of different schedules of feeding on daily rhythms of blood urea and ammonia concentration in cows  

Microsoft Academic Search

Many physiological processes of domestic animals exhibit daily rhythmicity. The goal of the present study was to investigate, in cows, the influence of different schedules of feeding on daily rhythms of blood urea and ammonia concentrations. Fifteen Italian Brown cows, from the same farm, clinically healthy and placed at the same environmental temperature and photoperiod, were used for this study.

Giuseppe Piccione; Fortunata Grasso; Francesco Fazio; Anna Assenza; Giovanni Caola



Concentrations of lead in maternal blood, cord blood, and breast milk.  

PubMed Central

Lead concentrations in maternal blood, umbilical cord blood, and breast milk from 114 women who were not occupationally exposed to lead were determined by graphite atomic absorption spectrophotometry. The mean concentrations of lead in maternal blood, umbilical cord blood and breast milk were 0.7, 0.55, and 0.23 mumol/l, respectively. A significant correlation was observed between maternal and umbilical cord blood (r = 0.63). A lower correlation was noted between maternal blood and breast milk (r = 0.29). These results suggest that lead freely crosses the placental barrier from mother to fetus and the transfer of this heavy metal from maternal tissues to breast milk is possible, but the metabolic mechanisms are more complicated. In addition, a longitudinal study was conducted of concentrations of lead in breast milk in nine lactating women. Results suggested no significant change in the content of lead in breast milk during early lactation.

Ong, C N; Phoon, W O; Law, H Y; Tye, C Y; Lim, H H



Essential trace and toxic element concentrations in organic and conventional milk in NW Spain.  


Dietary composition and husbandry practices largely determine essential trace element status and toxic element exposure of livestock, and consequently their concentrations in animal products. This study evaluates the main essential trace (Co, Cr, Cu, Fe, I, Mn, Mo, Ni, Se and Zn) and toxic (As, Cd, Hg and Pb) element concentrations in milk from organic and conventional farms in NW Spain (n=50). Milk samples were acid digested and analyzed by ICP-MS. Essential trace element concentrations in organic milk were significantly lower compared to conventional milk, this was especially evident for elements that are routinely supplemented at high concentrations in the conventional concentrate feed: Cu (41.0 and 68.9?g/L in organic and conventional milk, respectively), Zn (3326 and 3933?g/L), I (78 and 265?g/L) and Se (9.4 and 19.2?g/L). Toxic metal concentrations in milk were in general very low and no statistically significant differences were observed between organic and conventional milk. In addition, the mineral content of organic milk showed a seasonal pattern, the significantly higher As (65%) and Fe (13%) concentrations found in the winter sampling possibly being related to a higher consumption of concentration feed and soil ingestion when grazing. PMID:23391598

Rey-Crespo, F; Miranda, M; López-Alonso, M



Residual concentrations of the flukicidal compound triclabendazole in dairy cows' milk and cheese.  


Triclabendazole (TCBZ) is a flukicidal halogenated benzimidazole compound extensively used in veterinary medicine. Liver fluke control in lactating dairy cattle is difficult because treatment should be implemented only during the dry period to avoid milk residues. However, control in endemic areas is usually implemented as regular treatments three to four times a year, even during the lactating period. Thus, information on TCBZ milk excretion and the risk of the presence of drug residues in fluid milk and milk-derivate products is essential. The experimental aims were to evaluate the comparative disposition kinetics of TCBZ and its sulpho-metabolites in plasma and milk in lactating dairy cattle after the oral administration (12 mg kg(-1)) of TCBZ and to assess the pattern of residues in cheese made with milk from treated dairy cows. Both TCBZ sulphoxide and sulphone metabolites but not TCBZ were detected in milk (up to 36 and 144 h, respectively) and plasma (up to 144 h) after oral administration of TCBZ. Residual concentrations of TCBZ sulpho-metabolites were found in cheese made with milk from treated animals. The total average residual concentration in fresh cheese was 13.0-fold higher than that obtained in milk used for its elaboration. The high concentrations of TCBZ sulpho-metabolites recovered in fresh cheese should be seriously considered before milk from treated cows is used for making dairy products. PMID:21337234

Imperiale, F; Ortiz, P; Cabrera, M; Farias, C; Sallovitz, J M; Iezzi, S; Pérez, J; Alvarez, L; Lanusse, C



Salvage of blood urea nitrogen in sheep is highly dependent on plasma urea concentration and the efficiency of capture within the diegestive tract  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective was to establish the relationships between transfer of blood urea-N to the digestive tract (GIT) and utilisation of recycled urea-N within the GIT, and to determine which of these two mechanisms of the urea recycling process places greater limits on N salvage by growing sheep. Four gro...


Do Human Milk Concentrations of Persistent Organic Chemicals Really Decline During Lactation? Chemical Concentrations During Lactation and Milk/Serum Partitioning  

PubMed Central

Background Conventional wisdom regarding exposures to persistent organic chemicals via breast-feeding assumes that concentrations decline over the course of lactation and that the mother’s body burden reflects her cumulative lifetime exposure. Two important implications stemming from these lines of thought are, first, that assessments of early childhood exposures should incorporate decreasing breast milk concentrations over lactation; and, second, that there is little a breast-feeding mother can do to reduce her infant’s exposures via breast-feeding because of the cumulative nature of these chemicals. Objectives We examined rates of elimination and milk/serum partition coefficients for several groups of persistent organic chemicals. Methods We collected simultaneous milk and blood samples of 10 women at two times postpartum and additional milk samples without matching blood samples. Results Contrary to earlier research, we found that lipid-adjusted concentrations of polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and furans, and organochlorine pesticides in serum and milk do not consistently decrease during lactation and can increase for some women. Published research has also suggested an approximate 1:1 milk/serum relationship (lipid adjusted) on a population basis for 2,3,7,8-tetrachlorodibenzo-p-dioxin; however, our results suggest a more complex relationship for persistent, lipophilic chemicals with the milk/serum relationship dependent on chemical class. Conclusions Decreases in concentration of lipophilic chemicals on a lipid-adjusted basis during lactation should no longer be assumed. Thus, the concept of pumping and discarding early milk as means of reducing infant exposure is not supported. The hypothesis that persistent lipophilic chemicals, on a lipid-adjusted basis, have consistent concentrations across matrices is likely too simplistic.

LaKind, Judy S.; Berlin, Cheston M.; Sjodin, Andreas; Turner, Wayman; Wang, Richard Y.; Needham, Larry L.; Paul, Ian M.; Stokes, Jennifer L.; Naiman, Daniel Q.; Patterson, Donald G.



Factors Affecting the Concentration of Sphingomyelin in Bovine Milk1  

Microsoft Academic Search

Sphingomyelin is a phospholipid located in the outer leaflet of the plasma membrane of most cells and is a component of the milk fat globule membrane. Sphingo- myelin and its digestion products participate in several antiproliferative pathways that may suppress oncogen- esis. Although milk and dairy products are important sources of sphingomyelin in the human diet, little is known about

E. L. F. Graves; A. D. Beaulieu; J. K. Drackley




Microsoft Academic Search

Summary Increments of O, I, 2, 3, 4.5 and 6.5% crude protein equivalent (CPE) were added as urea to a basal diet containing 75% corn and 20% cottonseed hulls (8.3% protein from all natural sources) and fed to two nonlactating Holstein cows. Ruminal ammonia nitrogen (N) levels increased (P<.05) with each increment of urea and ranged from 1.3 (basal) to

J. H. Kang-Meznarich; G. A. Broderick; Texas A


The effects of colchicine and vincristine on the concentrations of glucose and related metabolites in goat's milk.  


The effects of colchicine and vincristine on the concentration of glucose and its metabolites in milk were studied following intramammary injection of the alkaloids into one mammary gland of lactating goats. Both alkaloids decreased the rate of milk secretion from the treated gland and produced similar changes in the concentrations of various metabolites in milk. The concentrations of glucose, UDP-galactose, galactose, pyruvate and lactate increased, while those of glucose 6-phosphate and phosphoenolpyruvate decreased in milk from treated glands. The rate of milk secretion from the untreated gland increased, along with the concentrations of glucose in the milk. The changes in the concentrations of the metabolites in milk are discussed in relation to possible biochemical changes occurring in the mammary gland during the suppression of milk secretion by the alkaloids. It is suggested that, before alkaloid treatment, the rate of milk secretion was limited by intracellular glucose supply. PMID:6498222

Faulkner, A; Henderson, A J; Peaker, M



Copper, lead and zinc concentrations of human breast milk as affected by maternal dietary practices  

Microsoft Academic Search

Maternal dietary practices have been found to affect the concentrations of some nutrients in human breast milk. Lead toxicity is a concern in young children. Lead, copper and zinc are thought to compete for intestinal absorption sites. The objective of the current project was to compare copper, lead and zinc contents of breast milk from practicing lacto-vegetarian and omnivore, lactating

J. Umoren; C. Kies




Microsoft Academic Search

SUMMARY Concentrations of porcine prolactin (PRL) were quantified by a newly developed radioimmuno- assay in blood serum and in milk collected from nine crossbred sows between 4 and 38 days after parturition. Litters were adjusted within 2 to 3 days after birth to 8, l0 or 12 pigs per sow. Blood and milk were sampled every 3 to 4 days

A. L. Mulloy; P. V. Malven


Influence of the Lactating Women Diet on the Concentration of the Lipophilic Vitamins in Human Milk  

Microsoft Academic Search

The aim of the study was to assess the intake of vitamins A and E by Polish breast feeding mothers and the correlation between the intake of these vitamins and their concentration in the maternal milk. Dietary intake was assessed by triple 24 h diet recall questionnaire. Milk samples were collected and the content of vitamin A and E was

Grazyna Duda; Malgorzata Nogala-Kalucka; Wanda Karwowska; Bogumila Kupczyk; Eleonora Lampart-Szczapa



Effects of feeding dairy cows different legume-grass silages on milk phytoestrogen concentration.  


Phytoestrogens are hormone-like substances in plants that can substantially influence human health (positively or negatively), and when fed to dairy cows are partly transferred to their milk. The aim of this study was to investigate the effects of varying the botanical composition and regrowth interval of legume-grass silage on phytoestrogen intake and milk phytoestrogen concentrations. In one experiment, 15 Swedish Red dairy cows were fed 2- or 3-cut red clover-grass silage, or 2-cut birdsfoot trefoil-grass silage. In a second experiment, 16 Norwegian Red dairy cows were fed short-term ley silage with red clover or long-term ley silage with white clover, and the effects of supplementation with ?-tocopherol were also tested. High concentrations of formononetin and biochanin A were found in all silage mixtures with red clover. The milk concentration of equol was highest for cows on the 2-cut red clover-grass silage diet (1,494 ?g/kg of milk). Because of the metabolism of biochanin A, genistein, and prunetin, their concentrations in milk and the apparent recovery were low. Coumestrol was detected in only short-term and long-term ley silage mixtures, and its milk concentration was low. Concentrations of secoisolariciresinol and matairesinol were higher in 2-cut birdsfoot trefoil-grass and long-term ley silage mixtures, those with legume species other than red clover, and the highest grass proportions. The 2-cut birdsfoot trefoil-grass silage diet also resulted in higher enterolactone concentration than the other diets (226 ?g/kg of milk). Lengthening the regrowth interval increased the intake of secoisolariciresinol and decreased the recovery of lignans. Feeding long-term ley silage resulted in higher milk lignan concentrations but lower milk isoflavone concentrations than feeding short-term ley silage. The apparent recovery of all phytoestrogens except prunetin was highest on the 2-cut birdsfoot trefoil-grass silage diet. No effect of ?-tocopherol supplementation was observed on milk concentrations of any of the measured phytoestrogens. Variations were observed in milk concentrations of phytoestrogens, especially of equol, among cows, which could not be explained by variations in diet composition or phytoestrogen intake. The results show that milk phytoestrogen concentration is strongly influenced by silage botanical composition, but questions regarding phytoestrogen metabolism remain to be answered. PMID:22818467

Höjer, A; Adler, S; Purup, S; Hansen-Mřller, J; Martinsson, K; Steinshamn, H; Gustavsson, A-M



Effect of milk allowance on concentrate intake, ruminal environment, and ruminal development in milk-fed Holstein calves.  


The aim of the present experiment was to test the hypothesis that a barley-based concentrate would induce an acidic ruminal environment in young calves and that increased milk allowance would alleviate this condition. Eight Holstein calves ruminally cannulated at d 7 +/- 1 of age were used to study the effect of variation in barley-based starter concentrate intake induced by 4 different milk allowances (3.10, 4.84, 6.60, and 8.34 kg of milk replacer/d; 123 g of dry matter/kg of milk) on the ruminal environment, blood variables, and fore-stomach development from wk 2 to 5 of age. Twelve ruminal fluid samples were collected during a weekly 24-h sampling in 4 consecutive weeks. Blood samples were collected by venipuncture between 1200 and 1300 h on ruminal sampling days. Rumen papillae development and visceral organ mass were recorded at slaughter. A linear treatment x week effect was observed for concentrate intake, with the calves fed the lowest milk allowance having the fastest increase in concentrate intake whereby these calves reached the same ME intake in wk 5 compared with calves with the highest milk allowance. Effects on ruminal variables were dominated by week of sampling, with minor differences among treatments. Ruminal pH was below 5.5 for 5 to 13 h/d and all calves with concentrate intake above 20 g of dry matter/d were observed to have a daily ruminal pH minimum at pH 5.5 or lower. The ruminal concentration of total volatile fatty acids (VFA) increased from 71 to 133 +/- 9 mmol/L in wk 2 to 5 and was characterized by a relatively high molar proportion of propionate, increasing from 34 to 40 mol/100 mol of VFA in wk 2 to 5. In addition, the presence of ethanol and propanol as well as numerous VFA esters points to a ruminal environment with a relatively high hydrogen pressure. Plasma glucose and insulin responded to the highest milk allowance in wk 2 to 4. Plasma VFA and ketone bodies increased with the lowest milk allowance in wk 4 to 5. At slaughter, empty wet weights of the rumen + reticulum and omasum as well as mass of digesta in these compartments were found to decrease linearly and perirenal fat was found to increase linearly with milk allowance, indicating that the milk allowance changed the body composition of the calves. Lengths of ruminal papillae in the atrium and ventral ruminal sac were not affected by treatment. We concluded that the ruminal environment of young calves fed a barley-based starter concentrate was characterized by a low ruminal pH and high VFA concentration regardless of the milk allowance. PMID:17699055

Kristensen, N B; Sehested, J; Jensen, S K; Vestergaard, M



Milk quality assessment in automatic milking systems: accounting for the effects of variable intervals between milkings on milk composition  

Microsoft Academic Search

Variation in milk yield and milk composition was studied in two commercial herds with automatic milking systems (AMS). All cows were milk recorded and milk sampled at all milkings throughout 48 h. All samples were analysed for fat, protein, lactose, urea and somatic cell count (SCC). The resultant data set for herd 1 included 606 milk samples from 138 cows,

N. C Friggens; M. D Rasmussen



Concentration of omega 3-polyunsaturated fatty acids of seal blubber oil by urea complexation: optimization of reaction conditions  

Microsoft Academic Search

Production of omega-3 fatty acid concentrates from seal blubber oil (SBO) was optimized. In this process, the content of total ?3-fatty acids, Y1; eicosapentaenoic acid (EPA), Y2; and docosahexaenoic acid (DHA), Y3 in the final product was maximized. A three-factor central composite rotatable design (CCRD) was used to study the effect of urea-to-fatty acid ratio (X1), crystallization time (X2), and

Udaya N Wanasundara; Fereidoon Shahidi



The effect of serum iron concentration on iron secretion into mouse milk  

PubMed Central

The concentration of iron in mouse milk is approximately 3 times that of the serum. Although there is clear evidence for the presence of the transferrin receptor in the rodent mammary gland, the precise mechanisms of iron transfer into milk are not known. Milk iron was linearly related to the serum iron:transferrin ratio in lactating mice whose serum iron ranged from 8 to 66 ?m. Increasing the iron binding capacity of the milk by 340 ?m by targeting the lactoferrin transgene to the mammary gland did not alter the relation between milk iron and the serum iron:transferrin ratio. The steady-state distribution ratio of 125I-transferrin between plasma and milk was about 0.2, indicating that transcytosed transferrin contributed a maximum of 6% of the milk iron. Fluorescently labelled transferrin incubated with the in situ gland localized mainly near the basal surface of the mammary alveolar cells. These experiments provide evidence that the initial and rate-limiting step in the transfer of iron into milk is binding to a basal transferrin receptor. A theoretical model of the relation between milk and serum iron suggests that the affinity of apotransferrin for the basal recycling system may be higher than observed in many other cell types.

Zhang, Peifang; Sawicki, Valerie; Lewis, Andy; Hanson, Linda; Monks, Jenifer; Neville, Margaret C



Rapid concentration of Bacillus and Clostridium spores from large volumes of milk, using continuous flow centrifugation.  


Deliberate or accidental contamination of foods such as milk, soft drinks, and drinking water with infectious agents or toxins is a major concern to health authorities. There is a critical need to develop technologies that can rapidly and efficiently separate and concentrate biothreat agents from food matrices. A key limitation of current centrifugation and filtration technologies is that they are batch processes with extensive hands-on involvement and processing times. The objective of our studies was to evaluate the continuous flow centrifugation (CFC) technique for the rapid separation and concentration of bacterial spores from large volumes of milk. We determined the effectiveness of the CFC technology for concentrating approximately 10(3) bacterial spores in 3.7 liters (1 gal) of whole milk and skim milk, using Bacillus subtilis, Bacillus atrophaeus, and Clostridium sporogenes spores as surrogates for biothreat agents. The spores in the concentrated samples were enumerated by using standard plating techniques. Three independent experiments were performed at 10,000 rpm and 0.7 liters/min flow rate. The mean B. subtilis spore recoveries were 71.3 and 56.5% in skim and whole milk, respectively, and those for B. atrophaeus were 55 and 59.3% in skim and whole milk, respectively. In contrast, mean C. sporogenes spore recoveries were 88.2 and 78.6% in skim and whole milk, respectively. The successful use of CFC to concentrate these bacterial spores from 3.7 liters of milk in 10 min shows promise for rapidly concentrating other spores from large volumes of milk. PMID:19343961

Agoston, Réka; Soni, Kamlesh A; McElhany, Katherine; Cepeda, Martha L; Zuckerman, Udi; Tzipori, Saul; Mohácsi-Farkas, Csilla; Pillai, Suresh D



Milk Yield and Composition of Lactating Cows Fed Steam-Flaked Sorghum and Graded Concentrations of Ruminally Degradable Protein  

Microsoft Academic Search

To determine the effect of various amounts of rumi- nally undegradable protein in the diets of lactating cows fed steam-flaked sorghum, 24 Holstein cows (90 ± 50 d in milk) were assigned to three treatments: 0.8% urea, 6% soybean meal, or 5% fish meal. Respec- tive percentages of ruminally undegradable protein in the diets (as a percentage of crude protein)

F. A. P. Santos; J. T. Huber; C. B. Theurer; R. S. Swingle; J. M. Simas; K. H. Chen; P. Yu



Physiological and Pathological Factors Influencing Bovine Immunoglobulin G1 Concentration in Milk  

Microsoft Academic Search

Bovine IgG2 concentration was de- termined by radial immunodiffusion in 355 milk samples of uninfected quar- ters, 101 milk samples of infected quar- ters, and 118 blood serum samples from 42 Holstein-Friesian cows taken at 30, 150, and 270 d. Concentration of IgG2 in blood serum (11.3 mg\\/ml) was highest at the beginning of lactation (30 d). Im- munoglobulin G2

J. P. Caffin; B. Poutrel; P. Rainard



Differences in Blood Urea and Creatinine Concentrations in Earthed and Unearthed Subjects during Cycling Exercise and Recovery  

PubMed Central

Contact of humans with the earth, either directly (e.g., with bare feet) or using a metal conductor, changes their biochemical parameters. The effects of earthing during physical exercise are unknown. This study was carried out to evaluate selected biochemical parameters in subjects who were earthed during cycling. In a double-blind, crossover study, 42 participants were divided into two groups and earthed during exercise and recovery. One group was earthed in the first week during 30 minutes of cycling exercise and during recovery, and a second group was earthed in the second week. A double-blind technique was applied. Blood samples were obtained before each training session, after 15 and 30 minutes of exercise, and after 40 minutes of recovery. Significantly lower blood urea levels were observed in subjects earthed during exercise and relaxation. These significant differences were noted in both groups earthed at the beginning of exercise (P < 0.0001), after 15 (P < 0.0001) and 30 minutes (P < 0.0001) of exercise, and after 40 minutes of relaxation (P < 0.0001). Creatinine concentrations in earthed subjects during exercise were unchanged. Conclusions. Earthing during exercise lowers blood urea concentrations and may inhibit hepatic protein catabolism or increase renal urea excretion. Exertion under earthing may result in a positive protein balance.

Sokal, Pawel; Jastrzebski, Zbigniew; Jaskulska, Ewelina; Sokal, Karol; Jastrzebska, Maria; Radziminski, Lukasz; Dargiewicz, Robert; Zielinski, Piotr



Differences in Blood Urea and Creatinine Concentrations in Earthed and Unearthed Subjects during Cycling Exercise and Recovery.  


Contact of humans with the earth, either directly (e.g., with bare feet) or using a metal conductor, changes their biochemical parameters. The effects of earthing during physical exercise are unknown. This study was carried out to evaluate selected biochemical parameters in subjects who were earthed during cycling. In a double-blind, crossover study, 42 participants were divided into two groups and earthed during exercise and recovery. One group was earthed in the first week during 30 minutes of cycling exercise and during recovery, and a second group was earthed in the second week. A double-blind technique was applied. Blood samples were obtained before each training session, after 15 and 30 minutes of exercise, and after 40 minutes of recovery. Significantly lower blood urea levels were observed in subjects earthed during exercise and relaxation. These significant differences were noted in both groups earthed at the beginning of exercise (P < 0.0001), after 15 (P < 0.0001) and 30 minutes (P < 0.0001) of exercise, and after 40 minutes of relaxation (P < 0.0001). Creatinine concentrations in earthed subjects during exercise were unchanged. Conclusions. Earthing during exercise lowers blood urea concentrations and may inhibit hepatic protein catabolism or increase renal urea excretion. Exertion under earthing may result in a positive protein balance. PMID:24066011

Sokal, Pawe?; Jastrz?bski, Zbigniew; Jaskulska, Ewelina; Sokal, Karol; Jastrz?bska, Maria; Radzimi?ski, Lukasz; Dargiewicz, Robert; Zieli?ski, Piotr



Effects of feed intake and dietary urea concentration on ruminal dilution rate and efficiency of bacteria growth in steers  

SciTech Connect

Four multiple-fistulated steers (340 kg) were fed a diet containing 50% ground grass hay, 20% dry distillers grains, and 30% concentrate at two intakes (7.2 or 4.8 kg DM/d). Urea (.4 or 1.2% of the diet) was infused continuously into the steers' rumens. The experimental design was a 4 x 4 Latin square with a 2 x 2 factorial arrangement of treatments. Infusing urea at .4 or 1.2% of the diet resulted in ruminal NH/sub 3/ N concentration of 4.97 and 9.10 mg/dl, respectively. Feeding steers at high rather than low intake decreased ruminal and total tract digestibilities of organic matter, NDF, and ADF but did not increase ruminal escape of N. However, apparent N escape from the rumen calculated using purines, but not /sup 15/N, as a bacterial marker was higher when 1.2 vs. .4% urea was infused. Feeding at high rather than at low intake increased the total pool of viable bacteria per gram organic matter fermented in the rumen. Although ruminal fluid outflows and particulate dilution rates were greater when steers were fed at high than low intakes, efficiencies of bacterial protein synthesis were unaffected by intake. The possibility of increased N recycling within the rumen with feeding at the higher intake is discussed.

Firkins, J.L.; Lewis, S.M. Montgomery, L.; Berger, L.L.; Merchen, N.R.; Fahey, G.C. Jr.



Iodine concentrations in cow's milk in Central and Northern Bohemia  

Microsoft Academic Search

Iodine deficiency and related risks of medical and\\/or developmental disorders in humans are a world - wide problem. In the last years, Czech endocrinologists and paediatricians have observed a significant increase in the occurrence of goitre in children and adolescents caused by a low dietary intake of iodine. Given the low consumption of seafood, milk and dairy products are the

A. Hejtmánková; E. Trnková; H. Dragounová


Effects of dietary histidine and arginine on plasma amino acid and urea concentrations of men fed a low nitrogen diet.  


The effects of dietary histidine and arginine on fasting and 1 and 2 hour postprandial plasma free amino acid and urea concentrations were studied in six young men. For 1 week each, they were fed six different diets containing 6.3 g of nitrogen daily. Each diet contained eight indispensable amino acids, cystine and tyrosine proportioned as in casein and a different mixture of dispensable nitrogen: A) six dispensable amino acids plus argine (diet 1) or plus histidine and arginine (diet 2) in the casein pattern, or B) an isonitrogenous amount of glycine and diammonium citrate alone (diet 3), with histidine (diet 4), with arginine (diet 5) or with histidine and arginine (diet 6). The fasting plasma concentrations of the seven indispensable amino acids assayed and their similar postprandial patterns were unaffected by the dietary treatments. Both fasting and postprandial plasma histidine concentrations were significantly lower when the histidine-low diets were fed than when the histidine-supplemented diets were fed. Histidine supplementation promoted a reduction in fasting plasma urea nitrogens. Proline concentrations were lowered significantly when proline was removed from the dietary amino acid mixtures, but plasma arginine concentrations were unaffected by arginine removal. Plasma histidine was maintained at lower concentrations in dietary histidine deficiency than when histidine was added to the low nitrogen diets. PMID:908966

Soon Cho, E; Krause, G F; Anderson, H L



Effects of peripartum biotin supplementation of dairy cows on milk production and milk composition with emphasis on fatty acids profile  

Microsoft Academic Search

Forty Holstein dairy cows receiving a 38% concentrate diet based on maize silage were assigned to either a control group, either a biotin group, receiving 20 mg of biotin per day from 15 days before expected calving date and for 120 days after calving. Milk production was measured daily, milk fat content, protein content, urea and somatic cell counts were determined weekly from

F. Enjalbert; M. C. Nicot; A. J. Packington



Optimal transport parameters of the inner medullary collecting duct in interaction between urine concentrating and urea excreting mechanisms: a computer simulation study.  


Although the accumulation of urea in the renal medulla is essential for the formation of concentrated urine, it is also necessary for the kidney to excrete considerable amounts of urea into the urine as a waste product of protein degradation. Thus, the urine concentrating capacity is attained by the interaction with the efficiency of urea excretion. To seek the best condition for this phenomenon, we developed an objective function for evaluating urea excreting capacity relative to urine concentrating capacity by using a mathematical model consisting of components of the countercurrent multiplication system: the ascending thin limb, capillary network, and inner medullary collecting duct. The values of the objective functions were calculated as three-dimensional functions of transport parameters for the inner medullary collecting duct, including hydraulic conductivity, urea permeability, and reflection coefficient for urea. The results of the computer analysis revealed that the maximum value of the objective function was attained when values for transport parameters of the inner medullary collecting duct corresponded to those experimentally obtained values reported previously. We conclude that the maximum urine concentrating capacity is limited by the efficiency of urea excreting capacity of the kidney, and vice versa. PMID:8938688

Hamada, Y; Taniguchi, J; Imai, M



Methionine Requirement of Weanling Large White x Landrace Pigs as Determined by Plasma Urea Concentration, Nitrogen Retention and Some Urinary Nitrogenous Components  

Microsoft Academic Search

The methionine requirements of weanling Large White x Landrace pigs fed a 20% protein cassava flour-soybean meal diet were evaluated using nitrogen balance, plasma urea concentration, urinary nitrogenous end products and the indexâ€\\



Effects of Abomasal or Intravenous Administration of Arginine on Milk Production, Milk Composition, and Concentrations of Somatotropin and Insulin in Plasma of Dairy Cows1  

Microsoft Academic Search

Holstein cows just past peak lactation were used in a 3 x 3 Latin square design to determine the effects of arginine infusion on concentrations of somato- tropin and insulin in plasma, milk pro- duction, and milk composition. Treat- ments were: 1) control; 2) arginine injection into jugular vein, and 3) arginine infusion into abomasum. Concentrations of arginine and ornithine

J. L. Vicini; J. H. Clark; W. L. Hurley; J. M. Bahr



Concentrated milk feeds and their relation to hypernatraemic dehydration in infants.  

PubMed Central

The composition of milks usually fed to 25 infants admitted to hospital with a dehydrating illness was studied. 15 hypernatraemic babies had been given feeds of greater sodium concentration and osmolality than those fed to the 10 infants whose plasma sodium was below 150 mEq/l. Hypernatraemic dehydration may be followed by death or permanent brain damage. Most infants in the survey were receiving milk with a sodium content greater than that advised by the manufacturers. Suggestions are made for reducing the sources of error commonly made in the reconstitution of dried milk formulae.

Chambers, T L; Steel, A E



Concentrated milk feeds and their relation to hypernatraemic dehydration in infants.  


The composition of milks usually fed to 25 infants admitted to hospital with a dehydrating illness was studied. 15 hypernatraemic babies had been given feeds of greater sodium concentration and osmolality than those fed to the 10 infants whose plasma sodium was below 150 mEq/l. Hypernatraemic dehydration may be followed by death or permanent brain damage. Most infants in the survey were receiving milk with a sodium content greater than that advised by the manufacturers. Suggestions are made for reducing the sources of error commonly made in the reconstitution of dried milk formulae. PMID:1242879

Chambers, T L; Steel, A E



Short communication: immediate and deferred milk production responses to concentrate supplements in cows grazing fresh pasture.  


The objective of this study was to determine the increase in milk production from supplementation that occurred after supplementation ceased. This portion of the total response (i.e., the deferred response), although accepted, is generally not accounted for in short-term component research projects, but it is important in determining the economic impact of supplementary feeding. Fifty-nine multiparous Holstein-Friesian dairy cows were offered a generous allowance of spring pasture [>45 kg of dry matter (DM)/cow per day) and were supplemented with 0, 3, or 6 kg (DM)/d of pelleted concentrate (half of the allowance at each milking event) in a complete randomized design. Treatments were imposed for the first 12 wk of lactation. Treatments were balanced for cow age (5.4 ± 1.68 yr), calving date (July 27 ± 26.0 d), and genetic merit for milk component yield. During the period of supplementation, milk yield and the yield of milk components increased (1.19 kg of milk, 0.032 kg of fat, 0.048 kg of protein, and 0.058 kg of lactose/kg of concentrate DM consumed), but neither body condition score nor body weight was affected. After concentrate supplementation ceased and cows returned to a common diet of fresh pasture, milk and milk component yields remained greater for 3 wk in the cows previously supplemented. During this 3-wk period, cows that previously received 3 and 6 kg of concentrate DM per day produced an additional 2.3 and 4.5 kg of milk/d, 0.10 and 0.14 kg of fat/d, 0.10 and 0.14 kg of protein/d, and 0.10 and 0.19 kg of lactose/d, respectively, relative to unsupplemented cows. This is equivalent to an additional 0.19 kg of milk, 0.006 kg of fat, 0.006 kg of protein, and 0.008 kg of lactose per 1 kg of concentrate DM previously consumed, which would not be accounted for in the immediate response. As a result of this deferred response to supplements, the total milk production benefit to concentrate supplements is between 7% (lactose yield) and 32% (fat yield) greater than the marginal response measured during the component experiment. Recommendations to dairy producers based on component feeding studies must be revised to include this deferred response. PMID:23375970

Roche, J R; Kay, J K; Rius, A G; Grala, T M; Sheahan, A J; White, H M; Phyn, C V C



[Urea as a substrate for the intestinal flora of the infant (author's transl)].  


The significance of the relatively high urea content of mothers milk for infant nutrition was investigated using 15N urea as a tracer by oral loading tests and an in-vitro culturing of bifidobacteria. The urea level of 6 mother's milk specimens was found to be 295 +/- 49 mg/l. There was a distinct incorporation of 15N into the intestinal bacterial fraction following 15N urea loadings in 3 infants, receiving mother's milk and 2 cows milk formulas which contained 1.8 and 2.1% of protein. The incorporation rate did not differ between the single types of feeding. In contrast to these findings the 15N incorporation into the bacterial flora of an infant suffering from kidney insufficiency was about 30 times higher than in healthy infants. Bifidobacteria infants derived from the feces of a breastfed infant utilised 15N from 15N urea added to the culture medium in concentrations of 20 mg per 100 ml. After incubating the culture for 2 days at 37 degrees C the 15N-excess of nitrogen fraction of the bifidobacteria amounted to 0.47 atom-%. Urea therefore can directly serve as a substrate for bifidobacteria on mother's milk feeding. PMID:7110147

Heine, W; Grütte, F; Wutzke, K; Stolpe, H J; Thiess, M; Müller, W



Yeast-fermented cassava chip protein (YEFECAP) concentrate for lactating dairy cows fed on urea–lime treated rice straw  

Microsoft Academic Search

The objective of this study was to study the effect of YEFECAP (yeast-fermented cassava chip) in replacing soybean meal (SBM) in concentrate mixtures. Four, early lactating (30±13day-in-milk) Holstein Friesian crossbred cows (50×50; HF×Native Thai cattle) were randomly assigned according to a 4×4 Latin square design to receive 4 dietary treatments (4 replacement levels of SBM by YEFECAP at 0, 33,

M. Wanapat; S. Polyorach; V. Chanthakhoun; N. Sornsongnern



Relation of a Seafood Diet to Mercury, Selenium, Arsenic, and Polychlorinated Biphenyl and Other Organochlorine Concentrations in Human Milk  

Microsoft Academic Search

Human transition milk was sampled from 88 mothers at the Faroe Islands, where the seafood diet includes pilot whale meat and blubber. Milk mercury concentrations (median, 2.45 ?g\\/liter) were significantly associated with mercury concentrations in cord blood and with the frequency of pilot whale dinners during pregnancy. Milk selenium concentrations (mean, 19.1 ?g\\/liter) correlated significantly with concentrations in cord blood

P. Grandjean; P. Weihe; L. L. Needham; V. W. Burse; D. G. Patterson; E. J. Sampson; P. J. Jorgensen; M. Vahter



Breast-milk mercury concentrations and amalgam surface in mothers from Brasília, Brazil  

Microsoft Academic Search

Human milk is the best source of nourishment for the newborn because of its incomparable balanced nutrition and psychological\\u000a benefits to the infant's development. Dental fillings containing metallic Hg are the primary source of inorganic Hg contamination\\u000a of humans. We studied Hg concentrations in the breast milk of mothers during the first month (7–30 d) postnatal in relation\\u000a to the

Sérgio L. da Costa; Olaf Malm; José G. Dórea



Stable and radioiodine concentrations in cow milk: dependence on iodine intake  

Microsoft Academic Search

For testing the potential use of stable iodine as a countermeasure to reduce radioiodine transfer to milk, concentrations of stable iodine and radioiodine in the milk of dairy cows fed different amounts of stable iodine were measured. The results indicated that, compared to a normal average stable iodine intake of about 20mgd?1 for cows, low iodine dietary intake (<1.5mgd?1) resulted in

G. Voigt; P. Kiefer



Fluoride Concentrations in Saliva and Dental Plaque in Young Children after Intake of Fluoridated Milk  

Microsoft Academic Search

This study determined fluoride (F) concentrations in whole saliva and dental plaque after intake of fluoridated milk using a randomised crossover experimental design. Eighteen healthy children (6–8 years) were subjected to each of four different 3-day drinking regimens: (a) 200 ml F-free tap water; (b) 200 ml tap water with 1.0 mg F; (c) 200 ml standard milk, and (d)

L. G. Petersson; I. Arvidsson; E. Lynch; K. Engström; S. Twetman



Liquid chromatographic analysis of milk phospholipids with on-line pre-concentration  

Microsoft Academic Search

Two methods have been developed for the analysis of bovine milk phospholipid (PL) classes by NP-HPLC with evaporative light scattering detection. In the first method, a PVA-Sil guard column was used for the rapid determination of the major milk PL, phosphatidylethathanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM). In the second method, the guard column was used to pre-concentrate the PL,

Peter Fagan; Chakra Wijesundera



Influence of isopropyl alcohol concentration in urea solution on cloud point and solid point of dewaxed product  

SciTech Connect

The authors investigated the influence of isopropyl alcohol concentration in the urea solution on the gap between the cloud and solid points of the dewaxed oil in experiments on solutions of n-paraffins in a diesel fuel cut from Baku crudes. The quantity of n-paraffins remaining in the dewaxed product was determined by the adduct-formation method. The washed adduct was decomposed and the mixture of n-paraffins thus recovered was analyzed chromatographically. The results demonstrated the link between the completeness of extraction of high-molecular-weight n-paraffins from solution in fuels and the lowering of the cloud point.

Abdullaev, E.S.; Ismailov, A.G.; Gadzhiev, A.S.; Balayan, R.D.




Microsoft Academic Search

Tight import barriers cover many milk products, but import quotas or prohibitive tariffs have not covered imports of a variety of high-protein specialty products. These products without tariff rate quotas include various casein and milk protein concentrate products. In recent years, imports of milk protein products into the United States have received increasing attention from U.S. dairy interests. A simulation

Joseph Valdes Balagtas; Bradley J. Rickard; Daniel A. Sumner



Iron, zinc, and copper concentrations in breast milk are independent of maternal mineral status1-3  

Microsoft Academic Search

Background: Little is known about the regulation of iron, zinc, and copper in breast milk and the transport of these minerals across the mammary gland epithelium. Objective: The objective was to study associations between breast-milk concentrations of iron, zinc, and copper and maternal mineral status. Design: Milk samples from 191 Swedish and Honduran mothers were collected at 9 mo postpartum.

Magnus Domellöf; Bo Lönnerdal; Kathryn G Dewey; Roberta J Cohen; Olle Hernell


Vitamin Bi 2: low milk concentrations are related to low serum concentrations in vegetarian women and to methylmalonic aciduria in their infants13  

Microsoft Academic Search

In a group of 13 strict vegetarian and 6 om- nivorous lactating women, relationships were studied among maternal milk and serum vitamin B-l2, and milk vitamin B-12 and infant urinary methylmalonic acid (MMA) excretion. Milk vitamin B- 12 concentrations were lower in women consuming a strict vegetarian diet compared with an omnivorous diet. Milk vitamin B-l2 was inversely related to

Bonny L Specker; Anne Black; Lindsay Allen; Frank Morrow


Serum lutein concentrations in healthy term infants fed human milk or infant formula with lutein  

Microsoft Academic Search

Background  Lutein is a carotenoid that may play a role in eye health. Human milk typically contains higher concentrations of lutein than\\u000a infant formula. Preliminary data suggest there are differences in serum lutein concentrations between breastfed and formula-fed\\u000a infants.\\u000a \\u000a \\u000a \\u000a Aim of the study  To measure the serum lutein concentrations among infants fed human milk or formulas with and without added lutein.\\u000a \\u000a \\u000a \\u000a Methods  A

Jodi Bettler; J. Paul Zimmer; Martha Neuringer; Patricia A. DeRusso



Concentrations of Phthalate Metabolites in Milk, Urine, Saliva, and Serum of Lactating North Carolina Women  

PubMed Central

Background Phthalates are ubiquitous in the environment, but concentrations in multiple media from breast-feeding U.S. women have not been evaluated. Objectives The objective of this study was to accurately measure and compare the concentrations of oxidative monoester phthalate metabolites in milk and surrogate fluids (serum, saliva, and urine) of 33 lactating North Carolina women. Methods We analyzed serum, saliva, urine, and milk for the oxidative phthalate metabolites mono(3-carboxypropyl) phthalate, mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono(2-ethyl-5-hydroxyhexyl) phthalate, and mono(2-ethyl-5-oxohexyl) phthalate using isotope-dilution high-performance liquid chromatography tandem mass spectroscopy. Because only urine lacks esterases, we analyzed it for the hydrolytic phthalate monoesters. Results We detected phthalate metabolites in few milk (< 10%) and saliva samples. MECPP was detected in > 80% of serum samples, but other metabolites were less common (3–22%). Seven of the 10 urinary metabolites were detectable in ? 85% of samples. Monoethyl phthalate had the highest mean concentration in urine. Metabolite concentrations differed by body fluid (urine > serum > milk and saliva). Questionnaire data suggest that frequent nail polish use, immunoglobulin A, and fasting serum glucose and triglyceride levels were increased among women with higher concentrations of urinary and/or serum phthalate metabolites; motor vehicle age was inversely correlated with certain urinary phthalate concentrations. Conclusions Our data suggest that phthalate metabolites are most frequently detected in urine of lactating women and are less often detected in serum, milk, or saliva. Urinary phthalate concentrations reflect maternal exposure and do not represent the concentrations of oxidative metabolites in other body fluids, especially milk.

Hines, Erin P.; Calafat, Antonia M.; Silva, Manori J.; Mendola, Pauline; Fenton, Suzanne E.



The effect of roughage to concentrate ratio in the diet on nitrogen and purine metabolism in dairy cows  

Microsoft Academic Search

Four lactating dairy cows were used in two experiments to study the effects of the roughage to concentrate ratio in the diet on nitrogen balance, plasma urea, urinary urea, milk urea and urinary purine derivatives. The use of the allantoin to creatinine ratio in spot samples of urine as an index of the urinary allantoin excretion was also evaluated. Four

Horacio Leandro Gonda; Margareta Emanuelson; Michael Murphy



Goat milk with and without increased concentrations of lysozyme improves repair of intestinal cell damage induced by enteroaggregative Escherichia coli  

PubMed Central

Background Enteroaggregative Escherichia coli (EAEC) causes diarrhea, malnutrition and poor growth in children. Human breast milk decreases disease-causing bacteria by supplying nutrients and antimicrobial factors such as lysozyme. Goat milk with and without human lysozyme (HLZ) may improve the repair of intestinal barrier function damage induced by EAEC. This work investigates the effect of the milks on intestinal barrier function repair, bacterial adherence in Caco-2 and HEp-2 cells, intestinal cell proliferation, migration, viability and apoptosis in IEC-6 cells in the absence or presence of EAEC. Methods Rat intestinal epithelial cells (IEC-6, ATCC, Rockville, MD) were used for proliferation, migration and viability assays and human colon adenocarcinoma (Caco-2, ATCC, Rockville, MD) and human larynx carcinoma (HEp-2, ATCC, Rockville, MD) cells were used for bacterial adhesion assays. Goats expressing HLZ in their milk were generated and express HLZ in milk at concentration of 270 ?g/ml . Cells were incubated with pasteurized milk from either transgenic goats expressing HLZ or non-transgenic control goats in the presence and absence of EAEC strain 042 (O44:H18). Results Cellular proliferation was significantly greater in the presence of both HLZ transgenic and control goat milk compared to cells with no milk. Cellular migration was significantly decreased in the presence of EAEC alone but was restored in the presence of milk. Milk from HLZ transgenic goats had significantly more migration compared to control milk. Both milks significantly reduced EAEC adhesion to Caco-2 cells and transgenic milk resulted in less colonization than control milk using a HEp-2 assay. Both milks had significantly increased cellular viability as well as less apoptosis in both the absence and presence of EAEC. Conclusions These data demonstrated that goat milk is able to repair intestinal barrier function damage induced by EAEC and that goat milk with a higher concentration of lysozyme offers additional protection.



Equations for the Calculation of the Protein Catabolic Rate from Predialysis and Postdialysis Urea Concentrations and Residual Renal Clearance in Stable Hemodialysis Patients  

Microsoft Academic Search

Several simple equations exist for the calculation of Kt\\/V from predialysis (Cpre) and postdialysis (Cpost) measurements of urea concentration. Analogous equations are needed for precise determination of patient protein catabolic rate (nPCR) from Cpre and Cpost. In this study we develop three simple nPCR equations from urea mass balance theory. The equations, which include a term for residual function, may

Laurie J. Garred; William Tang; David L. Barichello; Bernard Canaud



Maternal milk concentration of zinc, iron, selenium, and iodine and its relationship to dietary intakes.  


The dietary intake of zinc (Zn), iron (Fe), selenium (Se), and iodine (I) of 31 lactating Mexican-American women attending the Hidalgo County WIC program in Rio Grande Valley (RGV), Texas was estimated from 24-h dietary recall interviews. Milk samples were obtained from lactating mothers who had infants 3 months of age and younger. Milk samples were collected in two visits to assess change in breast milk composition after 1-3 months postpartum: group A--after 30-45 days and group B--75-90 days. Dietary intakes indicated that the study participants had significantly inadequate percent energy intakes than the DRI (Dietary Recommended Intakes) percent recommended kilocalorie values but protein intakes were substantially higher than the percent recommended values. The estimated percent Zn, Fe, Se, and I intakes were also significantly lower than the DRI percent recommended values. The lactating mothers consumed significantly less Zn, Se, and I when compared to the Recommended Dietary Allowances (RDA) even though Fe intake was higher than the RDA value. Breast milk concentration of Zn, Fe, and Se were in agreement within the range of representative values for Constituents of Human Milk but I has significantly less concentration than the representative value. There was no statistically significant correlation observed between dietary intake and milk concentration of Zn, Fe, Se, and I. This study compares the estimated dietary intake of zinc, iron, selenium, and iodine to the concentration of these trace elements in the maternal milk of lactating women of Mexican-American heritage who attend the Rio Grande Valley WIC clinic. PMID:18802672

Hannan, Mohammad A; Faraji, Bahram; Tanguma, Jesus; Longoria, Norma; Rodriguez, R C



Effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and visceral organ growth of suckling calves.  


The objective was to evaluate effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and allometric growth of visceral organs in suckling calves. Holstein bull calves (n = 8; 3-4 days of age) were fed either a low amount (average 0.63 kgDM/day, LM) or high amount (average 1.15 kgDM/day, HM) of high protein milk replacer until they were slaughtered at 6 weeks of age. Body weight (BW) at 4, 5, and 6 weeks of age, feed intake, average daily gain, and feed efficiency were higher in the HM than LM calves. The HM group had higher plasma glucose at 3 and 4 weeks of age and insulin levels after the age of 4 weeks compared with LM calves whereas no effect was detected on plasma nonesterified fatty acid or urea nitrogen concentrations. The HM calves had greater empty body weight (EBW), viscera-free BW and most of the organs dissected than LM calves. Relative weights (% of EBW) of liver, spleen, kidneys, and internal fat were higher, whereas head and large intestine was lower in HM than LM calves. The results suggest that increased milk feeding levels would accelerate the growth of the body and specific organs. PMID:20163656

Kamiya, Mitsuru; Matsuzaki, Masatoshi; Orito, Hideki; Kamiya, Yuko; Nakamura, Yoshi-nori; Tsuneishi, Eisaku



Calcium and magnesium dietary intakes and plasma and milk concentrations of Nepalese lactating women.  


Dietary calcium and magnesium intakes of 26 Nepalese lactating women were determined from analysis of 24-h duplicate food and beverage composites. In addition, blood, urine, and milk samples were collected. The mean Ca intake of these Nepalese mothers, 482 +/- 249 mg/d, was less than half that of American lactating women yet the Ca concentration of the milk was similar for the two groups of women. The Nepalese mothers appeared to maintain milk Ca concentrations by an increase in bone resorption as demonstrated by an elevated excretion of hydroxyproline. The Nepalese women had a mean Mg intake of 353 +/- 28 mg/d. Two locally available foods considered special for lactating women, jwano and gundruk, were examined for nutrient content and found to contain high concentrations of Ca and Mg. Increased consumption of these locally grown foods could add substantially to the Ca and Mg intakes of these lactating women. PMID:3354499

Moser, P B; Reynolds, R D; Acharya, S; Howard, M P; Andon, M B



Dietary marine algae (Schizochytrium sp.) increases concentrations of conjugated linoleic, docosahexaenoic and transvaccenic acids in milk of dairy cows.  


Modification of milk fat to contain long-chain (n-3) fatty acids and increased concentrations of conjugated linoleic acid has potential for improving health of consumers. Natural modification of milk through nutritional manipulation of diets for dairy cows is preferable to post-harvest modification. The objectives of this study were to increase the concentrations of beneficial fatty acids in milk fat by feeding a diet rich in (n-3) fatty acids from algae to dairy cows. Cows were fed a control diet, a diet containing algae (Schizochytrium sp.) protected against ruminal biohydrogenation, or a diet containing unprotected algae for 6 wk. Feed intake and milk production were recorded daily. Milk samples were obtained weekly for analysis of milk composition and profile of fatty acids. Percentage of fat in milk of cows fed algae was lower (P < 0.01) than in milk from cows fed the control diet; however, energy-corrected milk production did not differ (P > 0.05). Inclusion of algae in diets decreased (P < 0.01) feed intake. Milk fat from cows fed algae contained greater (P < 0.01) concentrations of conjugated linoleic acid, (n-3) fatty acids (particularly docosahexaenoic acid), and transvaccenic acid. Concentrations of docosahexaenoic acid were greater (P < 0.01) in milk fat from cows fed protected algae compared to milk fat from cows fed unprotected algae. Milk fat from cows fed algae contained lower (P < 0.05) concentrations of total saturated fatty acids compared to cows fed the control diet. In conclusion, milk fat can be modified through nutritional management of dairy cows to provide more favorable fatty acids for consumers. PMID:10539783

Franklin, S T; Martin, K R; Baer, R J; Schingoethe, D J; Hippen, A R



Human milk oligosaccharide concentration and risk of postnatal transmission of HIV through breastfeeding123  

PubMed Central

Background: The inefficiency of HIV breast-milk transmission may be caused by the presence of immunologically active factors, including human milk oligosaccharides (HMOs). Objective: We investigated whether HMO concentrations are associated with a reduced risk of postnatal HIV transmission. Design: A nested case-control study was conducted within a larger cohort study of HIV-infected women and their infants followed from birth to 24 mo in Lusaka, Zambia. Breast-milk samples collected at 1 mo from 81 HIV-infected women who transmitted via breastfeeding, a random sample of 86 HIV-infected women who did not transmit despite breastfeeding, and 36 uninfected breastfeeding women were selected. Total and specific HMO concentrations were measured by HPLC and compared between groups with adjustment for confounders by using logistic regression. Results: HIV-infected women with total HMOs above the median (1.87 g/L) were less likely to transmit via breastfeeding (OR: 0.45; 95% CI: 0.21, 0.97; P = 0.04) after adjustment for CD4 count and breast-milk HIV RNA concentrations; a trend toward higher concentrations of lacto-N-neotetraose being associated with reduced transmission (OR: 0.49; 95% CI: 0.23, 1.04; P = 0.06) was also observed. The proportion of 3?-sialyllactose (3?-SL) per total HMOs was higher among transmitting than among nontransmitting women (P = 0.003) and correlated with higher plasma and breast-milk HIV RNA and lower CD4 counts. Neither Secretor nor Lewis status distinguished between transmitting and nontransmitting women. Conclusions: Higher concentrations of non-3?-SL HMOs were associated with protection against postnatal HIV transmission independent of other known risk factors. Further study of these novel, potentially anti-HIV components of breast milk is warranted. This trial was registered at as NCT00310726.

Kuhn, Louise; Kim, Hae-Young; Hsiao, Lauren; Nissan, Caroline; Sinkala, Moses; Kankasa, Chipepo; Mwiya, Mwiya; Thea, Donald M; Aldrovandi, Grace M



The effect of zinc (Zn) supplementation during lactation on maternal Zn status and milk Zn concentrations  

SciTech Connect

The objective of this study was to longitudinally evaluate the effect of a dietary Zn supplement on maternal Zn states and milk Zn concentrations under a randomized, controlled, double-blinded study design. Sixty women, 30 {plus minus} 3.8 yrs, received either 15 mg Zn/day or placebo through {ge} 7 mos. of lactation. Dietary intake data, biochemical indices of Zn status and milk Zn concentrations were obtained at monthly intervals. Three day test-weighing was done at 2 wks and 3, 5, and 7 mos. Overall mean daily dietary intake for the non-Zn-supplemented group (n = 28) was 12.9 {plus minus} 2.2 mg, and for the Zn-supplemented group (n = 32), 25.7 {plus minus} 2.9 mg, including an average of 14 mg/d from a supplement. Plasma Zn concentrations did not differ between groups across lactation. Milk Zn concentrations were similar to those published previously and did not differ in monthly means or rate of decline according to group. Maternal Zn outputs to the infants at 2 wks and 3, 5 and 7 mos. were 2.17 {plus minus} 0.7, 0.92 {plus minus} 0.4, 0.72 {plus minus} 0.3, and 0.48 {plus minus} 0.26, respectively. The data suggest that average maternal Zn intake of {ge}10 mg/day during lactation is sufficient to maintain adequate maternal Zn status and milk Zn concentrations.

Krebs, N.F.; Reidinger, C.; Westcott, J.L.; Hartley, S.; Hambidge, K.M. (Univ. Colorado, Denver (United States))



Effects of consumption of milk and milk constituents on plasma concentrations of gastric inhibitory polypeptide and metabolites in preruminant goat kids.  


Plasma concentrations of gastric inhibitory polypeptide (GIP) were measured in preruminant goat kids before and after consumption of milk, skimmed milk or solutions of milk fat, lactose, glucose or casein plus lactose. GIP concentrations increased significantly within 1 h of consumption of milk or milk fat, and were elevated for the remainder of the 5-h sampling period. The integrated mean change in GIP concentration during this period did not differ between these two meals. GIP levels were slightly increased above basal values 5 h after skimmed milk consumption, probably reflecting the absorption of a small amount of fat, but overall there was no significant GIP response to this or to any of the other test meals. The marked increase in GIP concentration after a milk feed indicates a physiological role for the hormone in preruminants but, in contrast to the situation in simple-stomached animals, carbohydrate absorption does not elicit GIP secretion in the preruminant goat. The data strongly suggest that fat is the major nutrient to stimulate GIP secretion in these animals. PMID:7852888

Martin, P A; Faulkner, A; McCarthy, J P



Effect of dietary organic zinc, manganese, copper, and cobalt supplementation on milk production, follicular growth, embryo quality, and tissue mineral concentrations in dairy cows.  


This study evaluated potential effects of organic trace mineral supplementation on reproductive measures in lactating dairy cows. Cows were blocked by breed and randomly assigned at dry-off to receive inorganic trace mineral supplementation (control; n = 32) or to have a portion of supplemental inorganic Zn, Cu, Mn, and Co replaced with an equivalent amount of the organic forms of these minerals (treatment; n = 31). Trace minerals were provided through control or treatment premixes fed at 100 g·cow(-1)·d(-1). Premixes were fed to dry cows (range = 40 to 72 d before calving) in 1.8 kg·cow(-1)·d(-1) concentrate pellets through a computer feeder to provide 40, 26, 70, and 100% of supplemented Zn, Mn, Cu, and Co, respectively, and to lactating cows (range = 69 to 116 d after calving) in a total mixed ration to provide 22, 14, 40, and 100% of supplemented Zn, Mn, Cu, and Co, respectively. Treatment increased milk production at wk 14 (P = 0.047) postcalving, milk urea N content (P = 0.039), and BW loss from calving to 1 mo postcalving (P = 0.040), and decreased milk fat percentage (P = 0.045) and BCS (P = 0.048). Treatment tended to increase milk production at wk 13 (P = 0.089) postcalving and endometrial tissue concentrations of Fe (P = 0.070), BW at mo 1 (P = 0.056), and milk protein percentage (P = 0.064). Treatment did not affect (P > 0.1) DMI, health events, first-wave follicular dynamics, first cycle luteal measures, embryo quality, liver trace mineral concentrations, or luteal trace mineral concentrations. Cows with a rectal temperature ?39°C at the time of AI had a smaller percentage of fertilized entities (P < 0.001). However, of the entities that were fertilized, the percentage of viable embryos, embryo quality, accessory sperm number, and embryo cell number were not affected (P > 0.1) by treatment. We conclude that replacing a portion of inorganic supplemental trace minerals with an equivalent amount of these organic trace minerals (Zn, Mn, Cu, and Co) increased milk production in mid-lactation, but did not affect postpartum follicular dynamics, embryo quality, or liver and luteal trace mineral concentrations. PMID:20817861

Hackbart, K S; Ferreira, R M; Dietsche, A A; Socha, M T; Shaver, R D; Wiltbank, M C; Fricke, P M



Effects of strain of Holstein-Friesian and concentrate supplementation on the fatty acid composition of milk fat of dairy cows grazing pasture in early lactation  

Microsoft Academic Search

The effect of a grain-based concentrate supplement on fatty acid (FA) intake and concentration of milk FA in early lactation was investigated in grazing dairy cows that differed in their country of origin and in their estimated breeding value for milk yield. It was hypoth- esized that Holstein-Friesian cows of North American (NA) origin would produce milk lower in milk

W. J. Wales; E. S. Kolver; A. R. Egan; R. Roche



Effects of feeding Yucca schidigera extract in diets varying in crude protein and urea contents on growth performance and cecum and blood urea and ammonia concentrations of rabbits  

Microsoft Academic Search

Yucca extract (YE) has ammonia-binding properties. It was hypothesized that by binding ammonia in the cecum, YE could influence cecal utilization of crude protein (CP) and dietary urea. Two experiments were undertaken using New Zealand White weanling rabbits (5–6 weeks of age). In both experiments, YE was mixed at 250 mg kg?1 of diet, and six individually fed rabbits were

I. Hussain; A. M. Ismail; P. R. Cheeke



Depressive Symptoms during Pregnancy and the Concentration of Fatty Acids in Breast Milk  

PubMed Central

The aim of the present study was to examine the association between depressive symptoms in pregnancy and the concentration of long-chain polyunsaturated fatty acids (LCPUFAs) in breast milk. Women (n =287) enrolled in the Pregnancy, Infection, and Nutrition Study completed the Center for Epidemiologic Studies Depression Scale in pregnancy (<20 and 24–29 weeks) and had LCPUFAs measured in breast milk (4 months postpartum). Multiple linear regression was used to examine associations between depressive symptoms and breast milk LCPUFAs. Increasing depressive symptoms at <20 weeks were associated with lower docosahexaenoic acid concentrations (adjusted ?=?1.15, 95% confidence interval =?2.12, ?0.19). No similar associations were observed with other fatty acids nor between symptoms at 24–29 weeks and LCPUFAs. Depressive symptoms, even in the subclinical range, early in pregnancy are inversely associated with breast milk docosahexaenoic acid. This may have implications for the timing of screening and interventions for perinatal depression and the nutritional value of breast milk.

Keim, Sarah A.; Daniels, Julie L.; Siega-Riz, Anna Maria; Dole, Nancy; Herring, Amy H.; Scheidt, Peter C.



Short communication: effect of grazing on the concentrations of total sialic acid and hexose in bovine milk.  


Sialic acid, which is located at the terminal end of glycoconjugates, is believed to have important biological functions. Its concentration in bovine milk varies depending on lactation stage and season. However, it remains unclear whether dietary factors, especially fresh forage, affect the total sialic acid concentration in milk. The purpose of the present study was to investigate the effect of grazing on the concentrations of total sialic acid and hexose in bovine milk. Six healthy dairy cows were used in a crossover design (3 cows fed fresh forage and 3 cows fed grass silage) for 2 wk. Individual milk samples were collected at 2 consecutive milkings (morning and evening) at 0, 1, 3, 5, 8, 11, and 14 d of the experimental period, and 2 consecutive samples in each cow were combined on each sampling day in proportion of the morning and evening milk yields. No differences in body weight, milk yield, or milk composition were observed between the 2 groups during the experimental period. The hexose concentration in milk did not differ between these groups during the experimental period. Conversely, the total sialic acid concentration in the milk of each grazing cow significantly increased at 11 and 14 d of the experimental period compared with that at 0 d. In the grass silage group, the total sialic acid concentration at the end of the experimental period tended to be lower than that at 0 d, but the decrease was not significant. These results indicate that grazing management could have increased the concentration of sialoglycoconjugates in milk. This suggests that grazing may increase the biological function of milk because it is thought that sialic acid is significant in many ways. PMID:20855019

Asakuma, S; Ueda, Y; Akiyama, F; Uemura, Y; Miyaji, M; Nakamura, M; Murai, M; Urashima, T



Origin of starch in dairy concentrates provokes differences in milk fatty acids related to lifestyle diseases  

Microsoft Academic Search

The aim of this study was to evaluate whether milk fatty acids were affected by dietary starch source. Four Holstein-Friesian cows were fed 4 diets in a 4×4 latin square design. Cows either received a control diet (CON; grass silage, ensiled beet pulp and concentrate mixture with 70% dried beet pulp) or diets in which the dried beet pulp of

B. Vlaeminck; Vuuren van A. M; D. Demeyer; V. Fievez



Determination of cholesterol concentration in human milk samples using attenuated total reflectance Fourier transform infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Results of an inexpensive and rapid evaluation of the cholesterol concentration in human milk using ATR-FTIR techniques are presented. The FTIR spectrum of pure cholesterol was characterized and quantitatively estimated in the region between 2800 and 3200 cm-1. 125 samples at different stages of lactation were analyzed. There were no differences between the cholesterol concentrations in the samples of early (1-3 months), medium (4-6 months), and late (> 6 months) lactation stages ( p = 0.096968). The cholesterol concentration ranged from 4.30 to 21.77 mg/100 cm3. Such a broad range was due to the differences between the samples from different women ( p = 0.000184). The results indicate that ATR-FTIR has potential for rapid estimation of cholesterol concentration in human milk.

Kamelska, A. M.; Pietrzak-Fie?ko, R.; Bryl, K.



Physiological and Pathological Factors Influencing Bovine ?-Lactalbumin and ?-Lactoglobulin Concentrations in Milk  

Microsoft Academic Search

Bovine a-lactalbumin and ~-lacto- globulin concentrations were determined by radial immunodiffusion in 354 milk samples from uninfected and 98 samples from infected quarters from 42 Holstein- Friesian cows taken at 30, 150, and 270 days of lactation. ~-Lactalbumin and 13-1actoglobulin concentrations were not affected by quarter location. The a- lactalbumin decreased at the end of lactation and in samples collected

J. P. Caffin; B. Poutrel; P. Rainard



Rheological properties of concentrated skim milk: influence of heat treatment and genetic variants on the changes in viscosity during storage.  


Heat treatment during manufacturing of milk powder is one of the most important tools for manipulation of its functional properties, and it is the basis of the classification of these proteins into low-, medium-, and high-heat types. Slight differences in the sequences of the major proteins in milk (genetic variants) seem to have also a significant effect in milk powder processing (U.S. patent). Therefore, the effects of high-temperature storage and heat treatment on skim milk of defined genetic variants of beta-lactoglobulin (beta-LG) were measured. The samples had 45% total solids, the temperature of aging was 50 degrees C, and the heat treatment was 90 degrees C for 10 min prior to evaporation. Measurements on shear rate and on apparent viscosity were determined for each sample. During storage of the concentrated milk, the apparent viscosity and yield values increased markedly, and the age-dependent increase in viscosity in heat-treated concentrated skim milks was much more pronounced than in those prepared from unheated skim milks. The increase in apparent viscosity and yield value with storage time was notably different for milks containing different genetic variants. Unheated concentrated milks containing the B variant of beta-LG showed the most rapid increase in apparent viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the A variant. In contrast, heat-treated concentrated milks containing the A variant of beta-LG showed the most rapid increase in viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the AB variant. The changes in apparent viscosity of concentrated milk were largely reversible under high shear during the early stages of storage, but samples stored for a long time showed irreversible changes in apparent viscosity. Particle size analysis confirmed irreversible aggregation and fusion of casein particles during storage. PMID:14558767

Bienvenue, Annie; Jiménez-Flores, Rafael; Singh, Harjinder



Genetic ancestry modifies fatty acid concentrations in different adipose tissue depots and milk fat.  


The objective of this study was to determine the effect of cow genetic strain on fatty acid (FA) profiles in adipose tissue and milk. Adipose samples from two subcutaneous (shoulder and tail-head) and three visceral (kidney channel, mesenteric and omental) depots were obtained post mortem from New Zealand (NZ; n = 8) and North American (NA; n = 8) Holstein-Friesian cows. At the time of slaughter cows were in similar body condition (NZ: 4.0 ± 0.03, NA: 4.0 ± 0.02; ± SD) and stage of lactation (NZ: 90 ± 11.2 d; NA: 83 ± 4.3 d; ± SD). Milk was collected during the a.m. milking prior to slaughter and milk fat was extracted. Adipose and milk fat FA were quantified using gas chromatography. NZ cows had a lower proportion of saturated FA in shoulder, tail-head and omental adipose tissue and a greater proportion of mono-unsaturated FA and an elevated ?9-desaturase index in shoulder and tail-head adipose tissue. The proportions of individual FA differed between adipose depots, with proportions of de-novo FA greater in subcutaneous compared with visceral adipose depots. Milk from NZ cows contained greater concentrations of short chain FA (C8 : 0-12 : 0) and CLA, and less cis-9 18 : 1 than milk from NA cows. Regression analysis identified moderate associations between milk FA and shoulder adipose tissue FA for 18 : 2 (R(2) = 0.24), 18 : 3 n - 3 (R(2) = 0.39), and polyunsaturated fatty acids (R(2) = 0.38). Results from this study support the hypothesis that genetic strain dictates FA profiles in adipose tissue and milk and may alter the metabolic status of the various adipose depots differently. The data further support the premise that genetic strain affects the metabolic status of the various adipose depots differently. Elucidating the mechanisms that regulate the different adipose depots in the NZ and NA strains will increase our understanding of tissue mobilization and replenishment. PMID:23445567

Meier, Susanne; Verkerk, Gwyneth A; Kay, Jane K; Macdonald, Kevin A; Roche, John R



Soy Protein Concentrate and Heated Soy Flours as Protein Sources in Milk Replacer for Preruminant Calves[1], [2] and [3  

Microsoft Academic Search

Thirty-two male calves (8\\/treatment) in Trial 1 and 41 male and female calves (10 or ll\\/treatment) in Trial 2 were fed milk replacers containing 100% of the total protein from milk sources or 25% from milk and 75% from a soy product: soy protein concentrate; commercial heated (fully cooked) soy flour; or experimental soy flour for 6 wk. The experimental

D. P. Dawson; J. L. Morrill; P. G. Reddy; H. C. Minocha; H. A. Ramsey



Modified water solubility of milk protein concentrate powders through the application of static high pressure treatment.  


The effects of high pressure (HP) treatment (100-400 MPa at 10-60 °C) on the solubility of milk protein concentrate (MPC) powders were tested. The solubility, measured at 20 °C, of fresh MPC powders made with no HP treatment was 66%. It decreased by 10% when stored for 6 weeks at ambient temperature (~20 °C) and continued to decrease to less than 50% of its initial solubility after 12 months of storage. Of the combinations of pressure and heat used, a pressure of 200 MPa at 40 °C applied to the concentrate before spray drying was found to be the most beneficial for improved solubility of MPC powders. This combination of pressure/heat improved the initial cold water solubility to 85%. The solubility was maintained at this level after 6 weeks storage at ambient temperature and 85% of the initial solubility was preserved after 12 months. The improved solubility of MPC powders on manufacture and on storage are attributed to an altered surface composition arising from an increased concentration of non-micellar casein in the milk due to HP treatment prior to drying. The improved solubility of high protein powders (95% protein) made from blends of sodium caseinate and whey protein isolate compared with MPC powders (~85% protein) made from ultrafiltered/diafiltered milk confirmed the detrimental role of micellar casein on solubility. The results suggest that increasing the non-micellar casein content by HP treatment of milk or use of blends of sodium caseinate and whey proteins are strategies that may be used to obtain high protein milk powders with enhanced solubility. PMID:22127220

Udabage, Punsandani; Puvanenthiran, Amirtha; Yoo, Jin Ah; Versteeg, Cornelis; Augustin, Mary Ann




Technology Transfer Automated Retrieval System (TEKTRAN)

Twenty-five wether lambs (34 +/- 0.9 kg) fitted with ruminal and abomasal infusion catheters were used in a completely randomized design to determine the effects of differing proportions of ruminal and abomasal casein infusion on urea-N recycling and N balance in lambs fed a high-concentrate diet (1...


Fattening Rambouillet lambs with corn stubble or alfalfa, slow intake urea supplementation or balanced concentrate  

Microsoft Academic Search

One hundred and sixty Rambouillet lambs (15.925±0.350kg\\/BW) were studied for 90 days with two treatments evaluating in situ DM disappearance, voluntary DM and OM intake, rumen degradation, rate of passage, NH3 and VFA concentrations, apparent digestibility, ruminal pH, total fermentable carbohydrates, and weight gains. The first diet (80 lambs plus two cannulated sheep) offered 1000g corn stubble (CS) per day,

M. A Galina; J. D Hummel; M Sánchez; G. F. W Haenlein



Determination of milk and blood concentrations of lipopolysaccharide-binding protein in cows with naturally acquired subclinical and clinical mastitis.  


Blood and milk concentrations of the acute phase protein lipopolysaccharide-binding protein (LBP) were evaluated in cows with naturally occurring mastitis. Blood and milk samples were collected from 101 clinically healthy dairy cows and 17 dairy cows diagnosed with clinical mastitis, and the LBP concentrations of the samples were measured by an ELISA. Concentrations of LBP were greater in the blood and milk of cows with clinical mastitis than in those with healthy quarters. Concentrations of LBP also differed between uninfected and subclinically infected quarters with low somatic cell count. Blood concentrations of LBP in cows with subclinical intramammary infections could not be differentiated from those of cows with all healthy quarters. Together, these data demonstrate that increased blood and milk concentrations of LBP can be detected in dairy cows with naturally acquired intramammary infections that cause clinical mastitis. PMID:19233791

Zeng, R; Bequette, B J; Vinyard, B T; Bannerman, D D



Distillers Grains, Brewers Grains, and Urea as Protein Supplements for Dairy Rations  

Microsoft Academic Search

SUMMARY Two lactation experiments were conducted with 20 Holstein cows each, fed coneen- trate mixtures containing corn distillers dried grains, brewers dried grains, and urea as crude protein (nitrogen) supplements to a low-protein concentrate lnixturo. The protein- deficient basal ration resulted in weight loss, lower milk yields, and lower fat percentages than the other mixtures, and these changes were observed

J. K. Loosli; R. G. Warner



Gastrointestinal development of dairy calves fed low- or high-starch concentrate at two milk allowances.  


The objective was to study the effect of type of concentrate with varying starch and fibre content on growth and gastrointestinal development in preweaned dairy calves. Thirty-two newborn Danish Holstein male calves were allocated to four treatment groups in eight blocks of four calves. An experimental low-starch, high-molasses, high-fibre (EXP) concentrate or a traditional high-starch (TRA) concentrate were fed either at a high (HIGH; 2 × 3.2 kg/day) or a low (LOW; 2 × 1.6 kg/day) whole milk allowance in a 2 × 2 factorial design. TRA contained 350 and EXP 107 g starch/kg dry matter (DM), whereas the NDF content was 136 and 296 g/kg DM, respectively. Metabolizable energy (ME) was 11.2 and 12.2 MJ ME/kg DM in EXP and TRA, respectively. All calves had free access to artificially dried grass hay (9.8 MJ ME/kg DM). Four calves were culled during the experiment. The calves were euthanized either at 38 (12 calves) or 56 days (16 calves) of age. Evaluated across both slaughter ages, there was no difference between TRA and EXP in concentrate and hay intake, rumen weight and papillation. EXP resulted in increased villi number in duodenum and jejunum compared with TRA. Concentrate intake and reticulo-rumen weight was higher for LOW compared with HIGH milk allowance, whereas live weight gain was 20% lower. The results show that a low-starch, high-molasses, high-fibre concentrate with 8% lower ME content tended to reduce daily gain compared with a traditional calf starter concentrate, but resulted in similar ruminal development in preweaned calves both on a high and a low milk allowance fed along with grass hay. Furthermore, the results suggest that the experimental concentrate stimulated intestinal villi growth over that of the traditional concentrate. PMID:22440766

Kosiorowska, A; Puggaard, L; Hedemann, M S; Sehested, J; Jensen, S K; Kristensen, N B; Kuropka, P; Marycz, K; Vestergaard, M



Relationship of rate of lean tissue growth and other factors to concentration of urea in plasma of pigs.  


The objectives of this study were 1) to investigate the relationship between plasma urea N concentrations (PUN) and lean tissue growth and 2) to compare the value of different variables, related to lean growth and renal function, to correct the relationship between dietary lysine concentration and PUN response for variation not related to amino acid adequacy. Forty-eight gilts (64.8 kg BW) were individually penned (blocks based on initial BW) for 50 d: a 10-d adjustment, a 35-d pretreatment, and a 5-d treatment period. During the pretreatment period, ADFI, urine specific gravity (SG), serum creatinine (SC), PUN, and daily fat-free carcass lean (DFFCL), empty body protein (DEBP), total carcass fat (DCF), and empty body lipid (DEBLI) depositions were measured. Partial correlation coefficients (ADFI effect removed) indicated a strong and inverse relationship between PUN and lean growth (DFFCL and DEBP) (r = -.88 and -.91, respectively, P < .01) and a positive relationship between PUN and fat deposition (DCF and DEBLI) (r = .66 and .54; respectively, P < .22). Treatments consisted of six dietary lysine concentrations (.475, .550, .625, .700, .775, and .850%). Initial and final BW in the treatment period were 103.3 and 107.7 kg, respectively. Pretreatment PUN (PUNO) was the pretreatment variable with the greatest R2 and the smallest MSE when used in the model describing the response of PUN (PUN1) to dietary lysine. The estimated lysine requirements from the PUN1 response corrected with either PUN0 or with the combination of PUN0, ADFI, DFFCL, DCF, SG, and SC were not (P > .05) different (.656 vs > 678%, respectively). We conclude that 1) PUN concentrations have a potential value as an indicator of the efficiency of lean tissue growth and 2) pretreatment PUN is a useful variable to correct treatment PUN for variation not related to amino acid adequacy. PMID:8655440

Coma, J; Zimmerman, D R; Carrion, D



Concentration dependent effects of dextran on the physical properties of acid milk gels.  


The effect of dextran from Leuconostoc mesenteroides (DEX500), added to milk prior to acidification with glucono-?-lactone (GDL) or Streptococcus thermophilus DSM20259, was studied with respect to polysaccharide concentration. The incorporation of 5-30g/kg DEX500 significantly affected gelation behavior. Increasing DEX500 concentrations resulted in a linear increase of gel stiffness (GDL gels: R(2)=0.96; microbial acidification: R(2)=0.94; P<0.05) and 30g/kg DEX500 resulted in a 2-fold higher stiffness compared to gels without polysaccharide. The respective stirred gels depicted a significant reduction in syneresis, which decreased from 30.4% (0g/kg DEX500) to 22.0% (30g/kg DEX500) for chemically acidified gels after 1 d of storage. Physical characteristics of DEX500 in aqueous solution were helpful to explain its behavior in the complex system milk. PMID:24053819

Mende, Susann; Peter, Michaela; Bartels, Karin; Dong, Tingting; Rohm, Harald; Jaros, Doris



Metals and trace element concentrations in breast milk of first time healthy mothers: a biological monitoring study  

PubMed Central

Background Breast milk is the best source of nutrition for the newborn infant. However, since all infants cannot be breast-fed, there is a need for background data for setting adequate daily intakes. Previously, concentration data on major essential elements and some toxic elements in breast milk, based on different analytical techniques, have been published. There is no recent study on a large number of metals and trace elements in breast milk, using a sensitive analytical method for determination of low element concentrations. Methods Breast milk concentrations of 32 metals and elements in early lactation (days 14-21) were determined in a random sample of first time Swedish mothers (n?=?60) using inductively coupled plasma mass spectrometry (ICPMS). Results There were small inter-individual concentration variations in the macroelements Ca, K, Mg, P and S, and striking similarities across studies and over time, supporting a tight regulation of these elements in breast milk. Large inter-individual and over time differences were detected for Na concentrations, which may reflect an increase in salt consumption in Swedish women. Large inter-individual differences were also detected for the microelements Co, Cr, Mn and Mo, and the toxic metals As, Cd, Pb, Sb and V. Arsenic and B were positively correlated with fish consumption, indicating influence of maternal intake on breast milk concentrations. Observed differences in breast milk element concentrations across studies and over time could be attributed to the timing of sampling and a general decline over time of lactation (Cu, Fe, Mo, Zn), a possible lack of regulation of certain elements in breast milk (As, B, Co, Mn, Se) and time trends in environmental exposure (Pb), or in some cases to differences in analytical performance (Cr, Fe). Conclusions This study provides reliable updated information on a number of metals and elements in breast milk, of which some have not previously been reported.



Effects of partial replacement of concentrate with feed blocks on nutrient utilization, microbial N flow, and milk yield and composition in goats.  


Two experiments were carried out to evaluate the effect of partial replacement of concentrate with 2 types of feed blocks (FB) on rumen protozoa numbers, nutrient utilization, microbial N flow to the duodenum, and milk yield and composition in goats. The concentrate included oat, corn grain, barley, soybean meal, salt, and vitamin-mineral mixture. The FB (types I and II) were composed of crude 2-stage olive cake (120 or 100g/kg), fava beans (0 or 400g/kg), barley (320 or 200g/kg), beet molasses (220 or 100g/kg), sunflower meal (180 or 0g/kg), quicklime (70 or 90g/kg), salt (60g/kg), urea (0 or 20g/kg), and vitamin-mineral mixture (30g/kg). In experiment 1, 6 adult, dry, nonpregnant, rumen-fistulated Granadina goats (46.9+/-2.15kg of BW) were used and 3 trials were carried out. In each trial, 2 goats were randomly assigned to receive 600g of alfalfa hay and 400g of concentrate (diet AC), 600g of alfalfa hay, 200g of concentrate, and FB I (diet ACBI), or 600g of alfalfa hay, 200g of concentrate, and FB II (diet ACBII) with 6 replications per diet. The FB were supplied ad libitum. The ratio of purine bases to N was higher in solid- and liquid-associated bacteria for FB goats than for AC goats. In experiment 2, 18 Granadina goats (39.6+/-1.89kg of BW) in the middle of the third lactation were used, and 3 trials were carried out by following a 3 x 3 Latin square experimental design. In every trial, 6 animals randomly received 1.0kg of alfalfa hay supplemented with 1.0kg of concentrate (diet AC) or 0.5kg of concentrate and FB I and II (diets ACBI and ACBII) with 18 replications per diet. The FB were supplied ad libitum. The intakes of organic matter and fat were higher with the AC diet than with the FB diets. The intake of acid detergent fiber was higher for FB-containing diets than for the AC diet. The neutral detergent fiber digestibility of FB diets was higher than that of the AC diet. Energy intake was higher for diets AC and ACBII than for ACBI. Microbial N flow was affected by diet. Milk yield was higher in goats fed the AC diet than in those receiving the FB diets. Conjugated linoleic acid content was higher in milk from FB than in milk from AC goats. Our study suggests that FB type II based on local ingredients could be used advantageously to reduce half of the amount of concentrate without detrimental effects on nutrient utilization, N value of the diet, and milk composition. The decrease of milk yield with ACBII compared with that obtained with the AC diet could be compensated by better quality of milk, decreased cost of feeding, and environmental advantage derived of including by-products in FB. PMID:20412923

Molina-Alcaide, E; Morales-García, E Y; Martín-García, A I; Ben Salem, H; Nefzaoui, A; Sanz-Sampelayo, M R



Effect of Helicobacter pylori infection on intragastric urea and ammonium concentrations in patients with chronic renal failure  

Microsoft Academic Search

AIM--To assess the value of measuring the gastric juice urea:ammonium ratio in detecting Helicobacter pylori infection in patients with chronic renal failure. METHODS--Twenty three (12 men) patients with established chronic renal failure and dyspepsia were studied. Gastric juice (2 ml) was aspirated during endoscopy to measure urea and ammonium. The upper gastrointestinal tract was routinely inspected and two antral biopsy

W D Neithercut; P A Rowe; A M el Nujumi; S Dahill; K E McColl



Effect of carbohydrate source and cottonseed meal level in the concentrate: IV. Feed intake, rumen fermentation and milk production in milking cows.  


Four early-lactation crossbred cows (82.5 % Holstein) were selected to investigate the effect of carbohydrate source and cottonseed meal level in the concentrate on rumen fermentation and milk production. Cows were randomly assigned to receive four dietary treatments according to a 2 × 2 factorial arrangement in a 4 × 4 Latin Square design. Factor A was carbohydrate source: cassava chip (CC) and CC + rice bran at a ratio 3:1 (CR3:1), and factor B was variation in the level of cottonseed meal (CM): low (LCM) and high (HCM) in isonitrogenous diets (180 g CP/kg DM). It was found that carbohydrate source did not affect feed intake, dry matter digestibility, rumen fermentation, microbial population, milk yield and composition, or economic return (P > 0.05). However, cows fed with CC had a higher population of amylolytic bacteria than cows fed with CR3:1 (P < 0.05). Cows fed with HCM had a higher total feed intake, milk yield and composition, and milk income when compared with cows fed on LCM although the concentrate and roughage intakes, dry matter digestibility, rumen fermentation, and microbial populations were similar between treatments (P > 0.05). In addition, the carbohydrate source and cottonseed meal level interactions were not significant for any parameter. It could be concluded that cassava chip and high level of cottonseed meal could usefully be incorporated into concentrates for dairy cows without impacting on rumen fermentation or milk production. PMID:22843214

Wanapat, Metha; Pilajun, Ruangyote; Rowlinson, Peter



Concentrations of polybrominated diphenyl ethers in matched samples of indoor dust and breast milk in New Zealand.  


Polybrominated diphenyl ethers (PBDEs) are present in many consumer goods. There is evidence that PBDEs are toxic to humans, particular young children. The purpose of this study was to assess indoor dust as an exposure source for PBDEs. Concentrations of 16 PBDEs were determined in dust samples from 33 households in New Zealand, and in breast milk samples from 33 mothers living in these households. Associations between dust and breast milk PBDE concentrations were assessed, and children's PBDE intake from breast milk and dust estimated. Influences of household and demographic factors on PBDE concentrations in dust were investigated. Indoor dust concentrations ranged from 0.1ng/g for BDE17 to 2500ng/g for BDE209. Breast milk concentrations were positively correlated (p<0.05) with mattress dust concentrations for BDE47, BDE153, BDE154, and BDE209 and with floor dust for BDE47, BDE183, BDE206, and BDE209. The correlation for BDE209 between dust and breast milk is a novel finding. PBDE concentrations in floor dust were lower from households with new carpets. The estimated children's daily intake of PBDEs from dust and breast milk was below U.S. EPA Reference Dose values. The study shows that dust is an important human exposure source for common PBDE formulations in New Zealand. PMID:23850586

Coakley, Jonathan D; Harrad, Stuart J; Goosey, Emma; Ali, Nadeem; Dirtu, Alin-Constantin; Van den Eede, Nele; Covaci, Adrian; Douwes, Jeroen; Mannetje, Andrea 't



The effect of steam-flaked and extruded full-fat soybeans on the concentration of conjugated linoleic acid in the milk fat of dairy cows  

Microsoft Academic Search

Conjugated linoleic acid (CLA) is naturally produced in ruminants and exerts many beneficial health effects to humans. Feeding dairy cows with extruded soybeans has been reported to boost the CLA concentration in milk. However, the impact of steam-flaking soybeans on milk CLA content remains unknown. To study the potential of feeding steam-flaked soybeans on enhancing the CLA concentration in milk,

Yanling Li; Qiyu Diao; Qingxiang Meng



The Analysis of Milk Components and Pathogenic Bacteria Isolated from Bovine Raw Milk in Korea  

Microsoft Academic Search

Bovine mastitis can be diagnosed by abnormalities in milk components and somatic cell count (SCC), as well as by clinical signs. We examined raw milk in Korea by analyzing SCC, milk urea nitrogen (MUN), and the percentages of milk components (milk fat, pro- tein, and lactose). The associations between SCC or MUN and other milk components were investigated, as well

Y. K. Park; H. C. Koo; S. H. Kim; S. Y. Hwang; W. K. Jung; J. M. Kim; S. Shin; R. T. Kim; Y. H. Park



Associations between milk progesterone concentration on different days and with embryo survival during the early luteal phase in dairy cows.  


The relationships between the concentration of milk progesterone and early embryo survival on Days 4-8 inclusive and between the concentration of progesterone on different days from Days 0-8 inclusive following ovulation and insemination were examined in dairy cows. The relationships were examined following 77 randomly chosen artificial inseminations to cows in standing oestrus. There was a significant (P < 0.05) linear and quadratic relationship between the concentration of milk progesterone on each of Days 4-6 after ovulation and the probability of embryo survival. There was no association (P > 0.05) between milk progesterone concentration and probability of embryo survival on Days 7 and 8 after ovulation. There were no associations between milk progesterone concentration on Days 0-2 and the concentrations on Days 4-7, however, progesterone concentrations on Days 4 and 5 were highly predictive of the concentration on Days 6 and 7, respectively. Overall, the results indicate that suboptimal progesterone support during the early luteal phase is likely to deleteriously affect embryo viability and in addition, that it is possible to predict milk progesterone concentrations during the early luteal phase based on earlier stage concentrations and thus identify cows at risk of early embryo loss. PMID:16207495

McNeill, R E; Diskin, M G; Sreenan, J M; Morris, D G



Polychlorinated biphenyl (PCB) and dichlorodiphenyl dichloroethylene (DDE) concentrations in the breast milk of women in Quebec.  

PubMed Central

OBJECTIVES: This study documented the concentration of polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE) in the breast milk of women from Quebec, Canada, and assessed the impact of various sociodemographic and lifestyle factors on these levels. METHODS: From 1988 to 1990, milk samples were obtained from 536 Quebec women and analyzed for seven PCB congeners and p,p'-DDE. Information was obtained on subjects' physical, sociodemographic, and lifestyle characteristics. RESULTS: Mean concentrations were 0.52 mg/kg lipids (95% confidence interval [CI] = 0.50, 0.54) and 0.34 mg/kg lipids (95% CI = 0.32, 0.35) for PCBs (Aroclor 1260) and DDE, respectively. Age and history of breast-feeding showed statistically significant correlations with PCB and DDE concentrations. CONCLUSIONS: Concentrations of PCBs and DDE measured in this study are at the lower end of the concentration range recently reported for women living in industrialized countries. The modulating factors identified here should be considered when conducting studies on organochlorine exposure and disease.

Dewailly, E; Ayotte, P; Laliberte, C; Weber, J P; Gingras, S; Nantel, A J



Time-response relationship of ractopamine feeding on growth performance, plasma urea nitrogen concentration, and carcass traits of finishing pigs.  


Ractopamine hydrochloride (RAC) improves swine production efficiency by redirecting nutrients to favor muscle accretion rather than fat deposition. In the present study, the time-dependent effect of RAC feeding on performance, plasma urea N (PUN) concentrations, and carcass traits of finishing pigs were evaluated. In a 28-d growth study, 80 barrows (average initial BW = 69.4 ± 7.9 kg) were assigned to 1 of 5 treatments in a randomized complete block design with 8 replicate pens per treatment and 2 pigs per pen. The pigs were fed a corn-soybean meal-based diet with no added RAC (control) or 10 mg of RAC/kg fed for 7, 14, 21, or 28 d before slaughter. All diets were formulated to contain 0.88% standardized ileal digestible Lys (1.0% total Lys) and 3.23 Mcal of ME/kg. Individual pig BW and pen feed disappearance were recorded weekly to determine BW changes, ADG, ADFI, and G:F. Anterior vena cava blood samples were taken on d 28 for determination of PUN concentrations. After 28 d on trial, the pigs were slaughtered and carcass measurements made at 24 h postmortem. Overall, providing pigs with different RAC feeding durations did not affect the final BW and ADFI but resulted in a tendency (P = 0.09) for a linear increase in ADG and a linear improvement (P = 0.003) in G:F. No effect of RAC feeding was found for weekly ADFI. Weekly improvements (P < 0.05) in ADG and G:F were observed over the first 21 d of RAC feeding. However, the growth response declined (P < 0.05) in wk 4 of RAC treatment. The concentrations of PUN exhibited a quadratic decrease (P = 0.004) as the RAC feeding duration increased. Although RAC feeding did not affect any backfat measurements and carcass length, increasing the RAC feeding duration linearly increased HCW (P = 0.01), dressing percentage (P = 0.03), LM depth (P = 0.001), LM area (P < 0.001), muscle-to-fat ratio (P = 0.004), and predicted carcass lean percentage (P = 0.02). These results indicate that a greater growth rate was achieved within the first 21 d of RAC feeding whereas the magnitude of carcass response was directly dependent on the duration of RAC feeding. PMID:23307848

Almeida, V V; Nuńez, A J C; Schinckel, A P; Andrade, C; Balieiro, J C C; Sbardella, M; Miyada, V S



Effects of a polymer-coated urea product on nitrogen metabolism in lactating Holstein dairy cattle.  


The purpose of this study was to evaluate the impact of polymer-coated urea on nitrogen retention, rumen microbial growth, and milk production and composition. Coated urea (CU) that is more slowly hydrolyzed to ammonia than unprotected urea could potentially be used more efficiently by rumen microorganisms. Eight cows were offered each of three diets in a randomized crossover design. Each treatment period consisted of a 14-d adjustment period and a 5-d collection period. Diets were formulated to maintain milk production while reducing plasma urea nitrogen concentrations and urinary nitrogen excretion. Diets consisted of corn silage, mixed grass/legume haylage, chopped alfalfa hay, corn meal, protein, vitamin and mineral supplements, in a total mixed ration and fed ad libitum. The diets contained 17.9%, 18.1%, and 16.4% CP and 0, 0.77%, and 0.77% CU (dry matter basis) and are denoted as CP18-CU, CP18+CU, and CP16+CU, respectively. Individual feed intakes were measured, and total fecal, and urine collections were conducted. Cows were milked twice daily at 0500 and 1700 h, and the milk sampled for composition and milk urea N analysis. Dry matter intake averaged 23.5 +/- 0.2 kg/d and was not altered by diet. Also, milk fat and true protein were not altered by diet and averaged 3.72 and 3.07%, respectively. Milk yield was highest for diets CP18-CU and CP18+CU. Significant differences were observed in N intake and excretion in urine, feces, and milk between dietary treatments. Cows fed CP16+CU consumed 11% less N than in CP18-CU. Cows fed CP18+CU showed the highest excretion of N in urine, and together with CP16+CU, the lowest N excretion in feces. Nitrogen excretion in milk was lower for cows fed CP16+CU. Calculated N balance was not significantly different between diets nor was it significantly different from zero. Efficiency of N capture in milk protein as a function of N intake was higher for animals on CP16+CU. Urinary excretion of purine derivatives was not different between diets, and estimated microbial CP was also similar. Coated urea was not effective at reducing nitrogen excretion by dairy cattle. PMID:12836952

Galo, E; Emanuele, S M; Sniffen, C J; White, J H; Knapp, J R



Concentration of thyroid hormones and prolactin in dairy cattle serum and milk at three stages of lactation  

SciTech Connect

Eighteen lactating Holstein cows were used with six each in early, mid, and late lactation. Blood samples were obtained on 7 successive d. Blood serum and milk were measured by radioimmunoassay for thyroxine, 3,5,3'-triiodothyronine, and 3,3',5'-triiodothyronine. Prolactin was also measured in serum by radioimmunoassay. Serum thyroxine increased as lactation progressed and milk production declined (50, 55, and 62 ng/ml). Serum concentrations of triiodothyronine and reverse triiodothyronine were unchanged throughout lactation. Prolactin in serum declined as lactation advanced linearly (14.4, 11.8, and 10.5 ng/ml). Concentrations of thyroxine and triiodothyronine in milk declined significantly between early and mid but not mid and late lactation. Reverse triiodothyronine in milk did not change over the lactation. Serum triiodothyronine contained 1200 to 1300 pg/ml, whereas that in milk was 200 to 300 pg/ml. Reverse triiodothyronine was over 300 pg/ml in serum and only 80 to 90 pg/ml in milk. Amounts of thyroxine and triiodothyronine available to offspring from milk were calculated to be minor sources (4 to 5%) of total requirements for maintenance of metabolic function.

Akasha, M.A.; Anderson, R.R.; Ellersieck, M.; Nixon, D.A.



Equations for the calculation of the protein catabolic rate from predialysis and postdialysis urea concentrations and residual renal clearance in stable hemodialysis patients.  


Several simple equations exist for the calculation of K1/V from predialysis (Cpre) and postdialysis (Cpost) measurements of urea concentration. Analogous equations are needed for precise determination of patients protein catabolic rate (nPCR) from Cpre and Cpost. In this study we develop three simple nPCR equations from urea mass balance theory. The equations, which include a term for residual function, may be applied to any session of the week for patient dialyzed three times weekly who are in steady state with respect to dialysis dose and protein catabolism. The precision of each equation was tested with Cpre Cpost data obtained from steady state simulations of 540 patients without residual renal clearance (KR) and 972 simulated patients with significant residual KR. The simplest equation has the form: [formula: see text] where V is urea distribution volume and a and d are constants varying with session of the week. When compared to nPCR values calculated from formal urea kinetic modeling, the error determined with this formula never exceeded 5% for the midweek or final session. A more complicated equation of the form: [formula: see text] provided nPCR estimates with a maximum error < 1.3% for any dialysis session of the week and for KR up to 4 ml/min for a 70-kg patient. The only data required for the latter equation are Cpre, Cpost, length of dialysis session, volume ultrafiltered (delta BW), and an approximate value of the patient's urea distribution volume. The proposed equations permit nPCR to be calculated simply and accurately for stable patients dialyzed three times a week. PMID:9262842

Garred, L J; Tang, W; Barichello, D L; Canaud, B



Effect of ?-casein concentration in cheese milk on rennet coagulation properties, cheese composition and cheese ripening  

Microsoft Academic Search

Effects of the use of a ?-casein powder to enrich cheese milk on rennet coagulation properties of milk, cheese composition and cheese ripening were investigated. Casein content of control milk was 2.5%, whereas that for the three enriched milks was adjusted with ?-casein powder at 2.7%, 2.9% and 3.1%. The ?-casein to ?-casein ratio of these cheese milks was, respectively,

Daniel St-Gelais; Sylvie Haché



Comparison of 2 enzyme immunoassays and a radioimmunoassay for measurement of progesterone concentrations in bovine plasma, skim milk, and whole milk.  


The objective of this study was to compare 2 enzyme immunoassays (EIAs) with a radioimmunoassay (RIA) as to sensitivity and accuracy in the measurement of the progesterone (P4) concentration in bovine plasma, skim milk, and whole milk. The 72 samples from 24 lactating dairy cows expected to have either a high P4 concentration (cows in diestrus or pregnant) or a low P4 concentration (cows in estrus or anestrus) were analyzed by RIA, solid-phase EIA (SPEIA), which included a solvent extraction step, or direct EIA (DEIA) without solvent extraction. The overall mean concentrations of P4 did not differ (P < 0.4) among the assays. However, for the cows that were in diestrus or pregnant, the mean P4 concentrations (and standard error) were higher (P < 0.03), regardless of sample type, with RIA than with SPEIA, at 7.3 (0.7) and 6.1 (0.6) ng/mL, respectively. When only the high-P4 samples analyzed by RIA were compared, the mean P4 concentration was higher (P < 0.001) in whole milk than in skim milk, at 9.8 (1.0) and 4.1 (0.7) ng/mL, respectively. Although the mean P4 concentrations in the low-P4 samples did not differ (P < 0.80) among assays, the proportions of cows with a P4 concentration > or = 1 ng/mL were 3%, 14%, and 44% for RIA, SPEIA, and DEIA, respectively (P < 0.01; DEIA > SPEIA > RIA). PMID:18214159

Colazo, Marcos G; Ambrose, Divakar J; Kastelic, John P; Small, Julie A



Nickel supplementation effect on the growth, urease activity and urea and nitrate concentrations in lettuce supplied with different nitrogen sources  

Microsoft Academic Search

Effect of nickel (Ni) in the nutrient solution on yield, N metabolism, and nitrate content of leafy vegetables is poorly understood. The aim of this nutrient solution culture experiment was to investigate the effects of Ni supplementation on the nitrogen (N) metabolism and growth of lettuce (Lactuca sativa L. cv. Baker) with either urea or nitrate as the N source.

Amir Hossein Khoshgoftarmanesh; Fatemeh Hosseini; Majid Afyuni



Growth, Health, and Blood Glucose Concentrations of Calves Fed High-Glucose or High-Fat Milk Replacers  

Microsoft Academic Search

The influence of age, carbohydrate- fat ratios of milk replacers, and devel- opment of ruminal function on growth, health, and bIood glucose concentrations were evaluated in calves. Colostrum-fed, 3-day-old Holstein bull calves were fed to 12 wk on one of three dietary treatments: 1) a high carbohydrate, low fat (60.5% glucose, 9.5% lactose, and 3% lard) milk replacer; 2) a

M. S. Wijayasinghe; N. E. Smith; R. L. Baldwin



Effect of Safflower Oil, Flaxseed Oil, Monensin, and Vitamin E on Concentration of Conjugated Linoleic Acid in Bovine Milk Fat  

Microsoft Academic Search

Conjugated linoleic acid (CLA) refers to a mixture of conjugated octadecadienoic acids of predominantly ruminant origin. The main isomer in bovine milk fat is the cis-9, trans-11 CLA. Interest in CLA increased after thediscoveryofitshealth-promotingproperties,includ- ing potent anticarcinogenic activity. Two experiments were conducted to evaluate dietary strategies aimed at increasing the concentration of CLA in bovine milk fat. Bothexperimentswereorganized asarandomizedcom- plete

J. A. Bell; J. M. Griinari; J. J. Kennelly



Influence of Air Intake on the Concentration of Free Fatty Acids and Vacuum Fluctuations During Automatic Milking  

Microsoft Academic Search

The main objective of the study was to determine whether the amount of air intake during quarter milk- ing influences the concentration of free fatty acids (FFA) and vacuum fluctuations at the teat end when milking automatically. Air intake in the teat cup was restricted from the normal inlet of 4.5 to 7 L\\/min to 1.7 and 0 L\\/min on

M. D. Rasmussen; L. Wiking; M. Bjerring; H. C. Larsen



Covariance among milking frequency, milk yield, and milk composition from automatically milked cows  

Microsoft Academic Search

Automatic milking systems allow cows voluntary access to milking and concentrates within set limits. This leads to large variation in milking intervals, both within and between cows, which further affects yield per milking and composition of milk. This study aimed to describe the degree to which differences in milking interval were attributable to individual cows, and how this correlated to

P. Lřvendahl; M. G. G. Chagunda



Effects of clover-grass silages and concentrate supplementation on the content of phytoestrogens in dairy cow milk.  


A 2 x 2 factorial continuous experiment was conducted with 28 Norwegian Red dairy cows in early lactation to compare milk content of phytoestrogens when feeding ad libitum white clover (WCS) or red clover (RCS) grass silages prepared from the second and third cut without and with 10 kg/d supplementation of a standard concentrate. The cows were offered either RCS or WCS for 88 d (period 1) and thereafter a mixed red clover-white clover-grass silage for 48 d (period 2). Total dry matter intake and milk yield were not affected by forage type but increased with concentrate supplementation. Intake of isoflavones was several times greater in RCS than in WCS, whereas intake of lignans was greater in WCS. Concentrate supplementation reduced the intake of most phytoestrogens. Compared with WCS, RCS diets yielded milk with a greater content of flavonoids, whereas milk from WCS diets had greater contents of the mammalian lignans enterodiol and enterolactone. The content of the isoflavan equol was particularly high in RCS diets. There was no apparent carryover effect of clover type on milk phytoestrogen content because there was no difference in content between the silage treatments 3 wk after the cows were transferred to the same silage diet (period 2). Concentrate supplementation reduced the milk contents of the flavonoids equol, biochanin A, and daidzein and increased the content of mammalian lignans. The effects of silage type and concentrate supplementation on milk contents of the individual phytoestrogens were related to the intake of the compound or its precursor, except for the effect of concentrate on mammalian lignans, for which the intake of the known precursors was also reduced. Overall, this study shows that feeding cows with silage containing red clover increases the milk content of flavonoids at both low and high concentrate supplementation levels, and decreases the content of nonflavonoids such as mammalian lignans, when compared with silage containing white clover. The increased content of phytoestrogens in milk may be important when the health benefits of milk are studied. PMID:18565930

Steinshamn, H; Purup, S; Thuen, E; Hansen-Mřller, J



Effects of conjugated linoleic acids and dietary concentrate proportion on performance, milk composition, milk yield and metabolic parameters of periparturient dairy cows.  


The study aimed to examine effects of supplemented conjugated linoleic acids (CLA) to periparturient cows receiving different concentrate proportions ante partum (a.p.) to investigate CLA effects on lipid mobilisation and metabolism. Compared to adapted feeding, a high-concentrate diet a.p. should induce a ketogenic metabolic situation post partum (p.p.) to better understand how CLA works. Sixty-four pregnant German Holstein cows had ad libitum access to partial mixed rations 3 weeks prior to calving until day 60 p.p. Ante partum, cows received control fat (CON) or a CLA supplement at 100 g/d, either in a low-concentrate (CON-20, CLA-20) or high-concentrate diet (CON-60, CLA-60). Post partum, concentrate proportion was adjusted, while fat supplementation continued. After day 32 p.p., half of the animals of CLA-groups changed to CON supplementation (CLA-20-CON, CLA-60-CON). A ketogenic metabolic situation p.p. was not achieved and therefore impacts of CLA could not be examined. Live weight, milk yield and composition, blood parameters remained unaffected by the treatments. Only a slightly reduced milk fat yield (not significant) was recorded for Group CLA-20. The proportion of trans-10,cis-12 (t10,c12) CLA in milk fat was significantly increased in CLA-groups compared to CON-groups. With the exception of a reversible CLA effect on milk fat in Group CLA-20, no post-treatment effects occurred. Dry matter intake (DMI) of Group CLA-60 was highest before calving, resulting in a significantly improved estimated energy balance after calving. Ante partum, net energy intakes were significantly increased in high-concentrate groups. Overall, supplemented CLA preparation did not relieve metabolism and lipid mobilisation of early lactating cows. But feeding CLA in a high-concentrate diet a.p. seems to increase DMI and thereby improve the energy balance of cows immediately after calving. PMID:23678986

Petzold, Maria; Meyer, Ulrich; Kersten, Susanne; Spilke, Joachim; Kramer, Ronny; Jahreis, Gerhard; Dänicke, Sven



Periparturient Changes in Secretion and Mammary Uptake of Insulin and in Concentrations of Insulin and Insulin-Like Growth Factors in Milk of Dairy Cows1  

Microsoft Academic Search

Mammary uptake of insulin from blood was quantified near parturition in nine dairy cows, some of which were milked prepartum to induce prepartum lactogenesis. Milk samples were immuno- assayed for concentrations of insulin, insulin-like growth factor I, and insulin- like growth factor II. Cows milked prepartum, but in which prepartum lactogenesis did not occur (denoted as unsuccessful group), had higher

P. V. Malven; H. H. Head; R. J. Collier; F. C. Buonomo



The essential mineral concentration of Torba yoghurts and their wheys compared with yoghurt made with cows', ewes' and goats' milks.  


Comparative studies on yoghurts made from cows', ewes' and goats' milks with respect to mineral concentrations are limited and warrant further investigation. The objective of this study was to analyse the gross chemical composition as well as the concentration of essential minerals in concentrated (torba) yoghurts made from cows', ewes' and goats' milk compared with those in regular yoghurts and wheys. The elements were determined by simultaneous inductively coupled plasma optical emission spectrometry. Ewe torba yoghurt was significantly higher in calcium, sodium, phosphorus, magnesium, selenium, zinc, cobalt, copper and iron concentrations compared with goat and cow torba yoghurts. It is recommended that torba yoghurts made from different types of milk may be considered an important source of phosphorus, calcium, magnesium, selenium and zinc over the regular yoghurts and wheys. Whey samples are also an excellent source of lactose as well as sodium and potassium. PMID:18608571

Güler, Zehra; Sanal, Hasan



Effect of bleaching permeate from microfiltered skim milk on 80% serum protein concentrate.  


Whey proteins that have been removed before the cheese-making process are referred to as "native" whey proteins or milk serum proteins. Because serum proteins isolated directly from milk are not exposed to the cheese-making process, they are free from functional or sensory effects arising from this process. Whey proteins used in food and beverage applications are largely derived from annatto-colored Cheddar cheese. Some of the annatto is left in the whey and this color is converted to a colorless compound by bleaching. The effect of bleaching serum proteins on flavor and functionality of spray-dried protein provides a platform to investigate the effect of bleaching free from the confounding effects of cheese manufacture. The objective of this study was to characterize and compare the sensory and functional properties of 80% milk serum protein concentrate (SPC80) produced from bleached and unbleached microfiltration (MF) permeate made from skim milk with and without added annatto color. Colored and uncolored MF permeates were bleached with benzoyl peroxide (BP) or hydrogen peroxide (HP), ultrafiltered, diafiltered, and spray-dried. The SPC80 from unbleached colored and uncolored MF permeates were manufactured as controls. All treatments were manufactured in triplicate. All SPC80 were evaluated by sensory testing, instrumental analyses, functionality, color, and proximate analysis. The HP-bleached SPC80 was higher in lipid oxidation compounds than BP-bleached or unbleached SPC80, specifically hexanal, heptanal, nonanal, decanal, and 2,3-octadienone. The HP treatments were higher in aroma intensity and cardboard and fatty flavors compared with the unbleached and BP-bleached SPC80. The SPC80 bleached with BP had lower concentrations of norbixin compared with SPC80 bleached with HP. Functionality testing demonstrated that HP treatments had more soluble protein after 10min of heating at 90°C and pH 4.6 and pH 7 compared with the no bleach and BP treatments, regardless of additional color. Foams generated from bleached SPC80 were more stable than those from unbleached SPC80, and those bleached with HP were lower in yield stress than other SPC80. Overall, HP bleaching destroyed less norbixin and caused more lipid oxidation and subsequent off-flavors than did BP bleaching. However, the heat stability of SPC80 was enhanced by HP bleaching compared with control treatments or BP bleaching. PMID:23295111

Campbell, Rachel E; Adams, Michael C; Drake, Maryanne; Barbano, David M



Studies on the increase in serum concentrations of urea cycle amino acids among subjects exposed to cadmium  

SciTech Connect

Itai-itai disease (I disease) is a combination of renal tubular damage and osteomalacia accompanied by osteoporosis among subjects exposed to cadmium (Cd). When the renal tubular damage progresses, the excretion of amino acids, especially, threonine, hydroxyproline, proline, citrulline, ornithine, arginine, etc. increase in urine. It was reported that the increase in urinary excretion of citrulline, arginine and ornithine may be associated with an inhibition of urea synthesis in the urea cycle. The authors have found that serum citrulline, arginine and ornithine also increased in I disease patients. In order to investigate the mechanism of the increase in these serum amino acids, comparative studies were performed using both healthy subjects and patients with renal disease as control groups.

Nishino, H.; Shiroishi, K. (Toyama Institute of Health (Japan)); Kagamimori, S.; Naruse, Y. (Toyama Medical and Pharmaceutical Univ. (Japan)); Watanabe, M. (Toyama Female Univ. (Japan))



Studies on the increase in serum concentrations of urea cycle amino acids among subjects exposed to cadmium  

SciTech Connect

Itai-itai disease (I disease) is a combination of renal tubular damage and osteomalacia accompanied by osteoporosis among subjects exposed to cadmium (Cd). When the renal tubular damage progresses, the excretion of amino acids, especially, threonine, hydroxyproline, proline, citrulline, ornithine, arginine increased in urine. It has been reported that the increase in urinary excretion of citrulline, arginine and ornithine may be associated with an inhibition of urea synthesis in the urea cycle. The authors have found that serum citrulline, arginine and ornithine also increased in I disease patients. In order to investigate the mechanism of the increase in these serum amino acids, comparative studies were performed using both healthy subjects and patients with renal disease as control groups.

Nishino, H.; Shiroishi, K.; Kagamimori, S.; Naruse, Y.; Watanabe, M.



Effects of Dietary Crude Protein Concentration and Degradability on Milk Production Responses of Early, Mid, and Late Lactation Dairy Cows  

Microsoft Academic Search

Three experiments were conducted to investigate the effect of crude protein (CP) concentration and ruminally undegraded protein (RUP) concentration on milk production and composition of dairy cows at three different stages of lactation. Experiments 1, 2, and 3 using 39, 40, and 39 Holstein cows were con- ducted for cows in early (wk 4 to 14 postpartum), mid (wk 19

K. F. Kalscheur; J. H. Vandersall; R. A. Erdman; R. A. Kohn; E. Russek-Cohen



Determination of the Heat Stability Profiles of Concentrated Milk and Milk Ingredients Using High Resolution Ultrasonic Spectroscopy  

Microsoft Academic Search

In the present work, we used high resolution ultra- sonic spectroscopy for the analysis of heat coagulation process inmilks. Two skimmilks recombinedfrom pow- der samples differing by their preheating treatments as well as dairy ingredients (phosphocasein, whey protein isolate, and a milk model) were monitored while sub- mitted to a temperature of 120°C. Three stages in the precoagulation and coagulation

L. Lehmann; V. Buckin



Comparison of composition and sensory properties of 80% whey protein and milk serum protein concentrates.  


Milk serum protein concentrates (SPC) are proteins found in cheese whey that are removed directly from milk. Because SPC are not exposed to the cheese-making process, enzymatic or chemical reactions that can lead to off-flavors are reduced. The objectives of this study were to identify and compare the composition, flavor, and volatile components of 80% protein SPC and whey protein concentrates (WPC). Each pair of 80% SPC and WPC was manufactured from the same lot of milk and this was replicated 3 times. At each replication, spray-dried product from each protein source was collected. Commercial 80% WPC were also collected from several manufacturers for sensory and volatile analyses. A trained sensory panel documented the sensory profiles of the rehydrated powders. Volatile components were extracted by solid-phase microextraction and solvent extraction followed by solvent-assisted flavor evaporation with gas chromatography-mass spectrometry and gas chromatography-olfactometry. Consumer acceptance testing of acidified 6% protein beverages made with 80% SPC and WPC produced in the pilot plant and with WPC from commercial sources was conducted. The SPC was lower in fat and had a higher pH than the WPC produced in the pilot plant or commercial WPC. Few sensory differences were found between the rehydrated SPC and WPC manufactured in this study, but their flavor profiles were distinct from the flavor of rehydrated commercial WPC. The pilot-plant WPC had higher concentrations of lipid oxidation products compared with SPC, which may be related to the higher fat content of WPC. There was a large difference in appearance between 80% SPC and WPC: solutions of SPC were clear and those of WPC were opaque. Concentrations of lipid oxidation products in commercial WPC were generally higher than those in pilot-plant SPC or WPC. Sensory profiles of the peach-flavored protein beverage included cereal, free fatty acid, and soapy flavors and bitter taste in beverages made from pilot-plant products, whereas cardboard flavors were detected in those made with commercial WPC. Consumer liking scores for the beverages made with SPC were ranked highest or equally high with beverages made with WPC for aroma, appearance, and mouthfeel, but the beverages made with SPC had lower flavor and overall liking scores compared with beverages made with 3 of the 4 WPC. PMID:20412896

Evans, J; Zulewska, J; Newbold, M; Drake, M A; Barbano, D M



Comparative physiology and architecture associated with the mammalian urine concentrating mechanism: role of inner medullary water and urea transport pathways in the rodent medulla.  


Comparative studies of renal structure and function have potential to provide insights into the urine-concentrating mechanism of the mammalian kidney. This review focuses on the tubular transport pathways for water and urea that play key roles in fluid and solute movements between various compartments of the rodent renal inner medulla. Information on aquaporin water channel and urea transporter expression has increased our understanding of functional segmentation of medullary thin limbs of Henle's loops, collecting ducts, and vasa recta. A more complete understanding of membrane transporters and medullary architecture has identified new and potentially significant interactions between these structures and the interstitium. These interactions are now being introduced into our concept of how the inner medullary urine-concentrating mechanism works. A variety of regulatory pathways lead directly or indirectly to variable patterns of fluid and solute movements among the interstitial and tissue compartments. Animals with the ability to produce highly concentrated urine, such as desert species, are considered to exemplify tubular structure and function that optimize urine concentration. These species may provide unique insights into the urine-concentrating process.(1) PMID:23364530

Pannabecker, Thomas L



Nutrient composition and concentrations of immunoglobulins in milk of sows supplemented with L-carnitine  

Microsoft Academic Search

Recent studies have shown that L-carnitine supplementation of sows increases growth of their piglets during the suckling period. In this study, the composition of the milk of sows supplemented with L-carnitine was determined to find out whether an altered milk composition could account for the increased growth rates of the piglets. Milk of 13 control sows and 14 sows supplemented

Carmen Birkenfeld; Holger Kluge; Klaus Eder



A meta-analysis of the effects of dietary protein concentration and degradability on milk protein yield and milk N efficiency in dairy cows.  


Data sets from North American (NA, 739 diets) and North European (NE, 998 diets) feeding trials with dairy cows were evaluated to investigate the effects of dietary crude protein (CP) intake and ruminal degradability on milk protein yield (MPY) and efficiency of N utilization for milk protein synthesis (MNE; milk N / N intake) in dairy cows. The NA diets were based on corn silage, alfalfa silage and hay, corn and barley grains, and soybean meal. The NE diets were based on grass silage, barley and oats grains, and soybean and rapeseed meals. Diets were evaluated for rumen-degradable and undegradable protein (RDP and RUP, respectively) concentrations according to NRC (2001). A mixed model regression analysis with random study effect was used to evaluate relationships between dietary CP concentration and degradability and MPY and MNE. In both data sets, CP intake alone predicted MPY reasonably well. Addition of CP degradability to the models slightly improved prediction. Models based on metabolizable protein (MP) intake predicted MPY better than the CP or the CP-CP degradability models. The best prediction models were based on total digestible nutrients (TDN) and CP intakes. Similar to the MPY models, inclusion of CP degradability in the CP (intake or concentration) models only slightly improved prediction of MNE in both data sets. Concentration of dietary CP was a better predictor of MNE than CP intake. Compared with the CP models, prediction of MNE was improved by inclusion of TDN intake or concentration. Milk yield alone was a poor predictor of MNE. The models developed from one data set were validated using the other data set. The MNE models based on TDN and CP intake performed well as indicated by small mean and slope bias. This meta-analysis demonstrated that CP concentration is the most important dietary factor influencing MNE. Ruminal CP degradability as predicted by NRC (2001) does not appear to be a significant factor in predicting MPY or MNE. Data also indicated that increasing milk yield will increase MNE provided that dietary CP concentration is not increased, but the effect is considerably smaller than the effect of reducing CP intake. PMID:19528599

Huhtanen, P; Hristov, A N



An investigation of FT-Raman spectroscopy for quantification of additives to milk  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this research, four chemicals, urea, ammonium sulfate, dicyandiamide, and melamine, were mixed into liquid nonfat milk at concentrations starting from 0.1% to a maximum concentration determined for each chemical according to its maximum solubility, and two Raman spectrometers—a commercial Nicolet...


Redberry juniper as a roughage source in lamb feedlot rations: performance and serum nonesterified fatty acids, urea nitrogen, and insulin-like growth factor-1 concentrations.  


Effects of replacing cottonseed hulls with dry redberry juniper leaves on performance and serum NEFA, urea N, and IGF-1 were investigated in Rambouillet lambs (n = 24, initial BW = 28.6 +/- 4.94 kg). In a study with 2 feeding periods (period 1 = 65% concentrate ration, 28 d; period 2 = 85% concentrate ration, 49 d), lambs were individually fed ad libitum treatment diets containing cottonseed hulls (control; CSH), one-half of the cottonseed hulls replaced by dry juniper leaves (CSHJ), or all the cottonseed hulls replaced by dry juniper leaves (JUN). Lamb BW was similar on d 0 and 14, but increasing juniper in the diet linearly reduced (P = 0.04) BW on d 28. Differences in BW during period 1 are attributed to ADG and average daily DMI linearly decreasing (P < 0.001) with increasing concentrations of juniper, with lambs fed CSH, CSHJ, or JUN diets having ADG of 0.34, 0.30, and 0.14 kg, respectively. Differences in average daily DMI are attributed to secondary compounds in the cottonseed hulls and juniper and nutrient-toxin interactions. Lambs fed CSHJ diets had the greatest (P = 0.04) G:F compared with lambs fed CSH and JUN during period 1. Lambs fed JUN diets tended to have the greatest (P = 0.09) NEFA concentrations during period 1, and increasing juniper in the diet linearly reduced (P = 0.006) serum urea N and IGF-1 on d 14 and 28, respectively. During period 2, intake and growth of lambs fed JUN diet rapidly increased, resulting in all lambs having similar ADG, DMI, G:F, and BW. When period 2 began (d 33), serum NEFA and urea N were similar (P > 0.12) among lambs, but serum IGF-1 tended to be linearly reduced (P = 0.09) by increasing juniper in the diet. At times during period 2, lambs fed CSHJ had the greatest (P < 0.02) serum urea N (d 40 and 82) and IGF-1 (d 54) concentrations. Results were interpreted to indicate that air-dried redberry juniper leaves can replace all of the cottonseed hulls in lamb feedlot rations. Feeding 30% juniper in the diet for a longer period of time during the initial feeding period probably would have further reduced growth performance. PMID:19966150

Whitney, T R; Muir, J P



Effect of protein degradability on milk production of dairy ewes.  


The objective of this experiment was to determine the effect of protein degradability of dairy sheep diets on milk yield and protein utilization across 2 levels of milk production. Three diets were formulated to provide similar energy concentrations and varying concentrations of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP): 12% RDP and 4% RUP (12-4) included basal levels of RDP and RUP, 12% RDP and 6% RUP (12-6) included additional RUP, and 14% RDP and 4% RUP (14-4) included additional RDP. Diets were composed of alfalfa-timothy cubes, whole and ground corn, whole oats, dehulled soybean meal, and expeller soybean meal (SoyPlus, West Central, Ralston, IA). Estimates of RDP and RUP were based on the Small Ruminant Nutrition System model (2008) and feed and orts were analyzed for Cornell N fractions. Eighteen multiparous dairy ewes in midlactation were divided by milk yield (low and high) into 2 blocks of 9 ewes each and were randomly assigned within block (low and high) to 3 pens of 3 ewes each. Dietary treatments were arranged in a 3 x 3 Latin square within each block and applied to pens for 14-d periods. We hypothesized that pens consuming high-RUP diets (12-6) would produce more milk and milk protein than the basal diet (12-4) and pens consuming high-RDP diets (14-4) would not produce more milk than the basal diet (12-4). Ewes in the high-milk-yield square consumed more dry matter and produced more milk, milk fat, and milk protein than ewes in the low-milk-yield square. There was no effect of dietary treatment on dry matter intake. Across both levels of milk production, the 12-6 diet increased milk yield by 14%, increased milk fat yield by 14%, and increased milk protein yield by 13% compared with the 14-4 and 12-4 diets. Gross N efficiency (milk protein N/intake protein N) was 11 and 15% greater in the 12-6 and 12-4 diets, respectively, compared with the 14-4 diet. Milk urea N concentration was greater in the 12-6 diet and tended to be greater in the 14-4 diet compared with the 12-4 diet, indicating that the excretion of urea N in this study was more closely related to dietary crude protein concentration than to protein degradability. PMID:19700712

Mikolayunas-Sandrock, C; Armentano, L E; Thomas, D L; Berger, Y M



Nitrogen balance and partitioning of some nitrogen catabolites in milk and urine of lactating cows  

Microsoft Academic Search

After calving, two groups of four cows were fed fescue hay (10 kg\\/d) and a concentrate (8 kg\\/d) containing 0 or 20 g kg?1 urea in order to induce different rumen microbial growth: the partition between the urine and milk excretion of allantoin, uric acid, creatinine and urea was examined. After 21 d of lactation, individual feed intakes, total faeces

P. Susmel; M. Spanghero; B. Stefanon; C. R. Mills



Urea Molasses Blocks to improve milk production and reproductive performance of cross-bred dairy cattle under smallholder farm condition in Bangladesh  

Microsoft Academic Search

Introduction Crop residues constitute more than 90% of the feed resources available for ruminal livestock in Bangladesh. The major crop residue is rice straw, which serves as the main feed for dairy cattle. Low quality straw based diets, feed scarcity, poor reproductive management and diseases results in a substantial decrease in milk production and reproductive performance of dairy cattle. Previous

M. A. S. Khan; M. A. R. Chowdhury


Effect of microfiltration concentration factor on serum protein removal from skim milk using spiral-wound polymeric membranes.  


Our objective was to determine the effect of concentration factor (CF) on the removal of serum protein (SP) from skim milk during microfiltration (MF) at 50°C using a 0.3-?m-pore-size spiral-wound (SW) polymeric polyvinylidene fluoride (PVDF) membrane. Pasteurized (72°C for 16 s) skim milk was MF (50°C) at 3 CF (1.50, 2.25, and 3.00×), each on a separate day of processing starting with skim milk. Two phases of MF were used at each CF, with an initial startup-stabilization phase (40min in full recycle mode) to achieve the desired CF, followed by a steady-state phase (90-min feed-and-bleed with recycle) where data was collected. The experiment was replicated 3 times, and SP removal from skim milk was quantified at each CF. System pressures, flow rates, CF, and fluxes were monitored during the 90-min run. Permeate flux increased (12.8, 15.3, and 19.0 kg/m(2) per hour) with decreasing CF from 3.00 to 1.50×, whereas fouled water flux did not differ among CF, indicating that the effect of membrane fouling on hydraulic resistance of the membrane was similar at all CF. However, the CF used when microfiltering skim milk (50°C) with a 0.3-?m polymeric SW PVDF membrane did affect the percentage of SP removed. As CF increased from 1.50 to 3.00×, the percentage of SP removed from skim milk increased from 10.56 to 35.57%, in a single stage bleed-and-feed MF system. Percentage SP removal from skim milk was lower than the theoretical value. Rejection of SP during MF of skim milk with SW PVDF membranes was caused by fouling of the membrane, not by the membrane itself and differences in the foulant characteristic among CF influenced SP rejection more than it influenced hydraulic resistance. We hypothesize that differences in the conditions near the surface of the membrane and within the pores during the first few minutes of processing, when casein micelles pass through the membrane, influenced the rejection of SP because more pore size narrowing and plugging occurred at low CF than at high CF due to a slower rate of gel layer formation at low CF. It is possible that percentage removal of SP from skim milk at 50°C could be improved by optimization of the membrane pore size, feed solution composition and concentration, and controlling the rate of formation of the concentration polarization-derived gel layer at the surface of the membrane during the first few minutes of processing. PMID:23891300

Beckman, S L; Barbano, D M



[Progesterone and pregnanediol-glucuronid concentrations in saliva, milk and urine of female alpacas and their application in pregnancy diagnosis].  


The objective of the present study was the measurement of the pregnancy associated hormones progesterone (P4) and pregnanediol-glucuronide (PdG) in saliva, milk and urine of alpacas and their potential use in pregnancy diagnosis. Sample of blood, saliva, milk and urine were obtained from 36 female alpacas before mating and throughout the pregnancy. Concentrations of P4 and PdG were determined using an enzyme immunoassay (EIA). Pregnancy was checked by ultrasonography at any sampling time. The milk samples were also tested using a commercial on-farm progesterone kit which was designed for dairy cattle. EIA-Concentrations of P4 in blood, milk and urine and urine PdG concentrations were significantly higher in pregnant than in not pregnant alpacas. There was no difference in concentrations of P4 or PdG in saliva. The accuracy of the progesterone kit was 90% for diagnosis of pregnancy and 69% for non-pregnancy. However, 70% of the false positive results also showed relatively high P4 milk concentrations in the EIA. Values of P4 in blood and PdG in urine are comparable to previous reports in alpacas and therefore can be confirmed as an indicator for pregnancy. Saliva seems unsuitable in pregnancy diagnosis in alpacas, whereas milk seems to be an adequate alternative. The use of milk and urine would simplify the pregnancy diagnosis in alpacas since in contrast to the current methods (e. g. blood progesterone) the owners can take the samples. The avoidance of blood sampling results in a considerable stress reduction for the animals. P4 measurement in milk and PdG measurement in urine are good alternatives in pregnancy diagnosis during the first month of pregnancy, when a trans-abdominal ultrasonographic examination is not yet reliable. However, since high values of P4 and PdG only show the presence of active luteal tissue and therefore are indirect markers of pregnancy the diagnosis should be confirmed using ultrasound later in pregnancy. PMID:21141281

Volkery, Janine; Wittek, Thomas; Sobiraj, Axel; Gottschalk, Jutta; Einspanier, Almuth


High-concentrate diets and polyunsaturated oils alter trans and conjugated isomers in bovine rumen, blood, and milk.  


Three Holstein cows were fed a high-concentrate diet (65:35 concentrate to forage) supplemented with either 5% sunflower oil (SO), 5% linseed oil (LO), or 2.5% fish oil (FO) to examine effects on biohydrogenation and fatty acid profiles in rumen, blood plasma, and milk. Diets were fed in a 3 x 3 Latin square with 4-wk periods with grass hay as the forage. Milk yield, dry matter intake, and percentages of milk fat (2.64) and protein (3.22) did not differ. All diets resulted in incomplete hydrogenation of unsaturated fatty acids as indicated by the profiles of 18:1 isomers, conjugated 18:2 isomers, nonconjugated 18:2 isomers, and 18:0 in ruminal fluid. Percentages of 8:0-14:0 and 16:0 in milk fat were greater with FO. Percentage and yield of trans10,cis12-18:2 were small and greater in cows fed SO (0.14%, 0.57 g/d) than FO (0.03%, 0.15 g/d) or LO (0.04%, 0.12 g/d). Percentage and yield of trans10-18:1, however, increased with FO (6.16%) and SO (6.47%) compared with LO (1.65%). Dietary FO doubled percentage of cis11-18:1 in rumen, plasma, and milk fat. Despite a lack of difference in ruminal percentage of trans11-18:1 (10.5%), cows fed FO had greater plasma trans11-18:1 (116 vs. 61.5 microg/mL) but this response did not result in greater trans11-18:1 percentage in milk fat, which averaged 5.41% across diets. Percentage (2.2%) and yield (14.3 g/d) of cis9,trans11-18:2 in milk fat did not differ due to oils. Unique responses to feeding LO included greater than 2-fold increases in percentages of trans13+14-18:1, trans15-18:1, trans16-18:1, cis15-18:1, cis9,trans12-18:2 and trans11,cis15 -18:2 in umen, plasma, and milk, and cis9,trans13-18:2 in plasma and milk. Ruminal 18:0 percentage had the highest positive correlation with milk fat content (r = 0.82) across all diets. When compared with previous data with cows fed high-concentrate diets without oil supplementation, results suggest that greater production of trans10-18:1, cis11-18:1, and trans11,cis15-18:2 coupled with low production of 18:0 in the rumen may be associated with low milk fat content when feeding high-concentrate diets and fish oil. In contrast, SO or LO could lead to low milk fat content by increasing ruminal trans10-18:1 (SO) or trans11,cis15-18:2 and trans9,trans12-18:2 (LO) along with a reduction in mammary synthesis of 8:0-16:0. Simultaneous increases in ruminal trans11-18:1 with fish oil, at a fraction of sunflower oil supplementation, may represent an effective strategy to maintain cis9,trans11-18:2 synthesis in mammary while reducing milk fat output and sparing energy. PMID:16230705

Loor, J J; Ferlay, A; Ollier, A; Ueda, K; Doreau, M; Chilliard, Y



Effect of subacute ruminal acidosis on milk fat concentration, yield and fatty acid profile of dairy cows receiving soybean oil.  


The objective of this study was to investigate the effect of ruminal infusion of soybean oil (SBO) with either a moderate- or high-forage diet on fat concentration, yield and composition in milk from dairy cows. Six rumen-fistulated Holstein dairy cows (639+/-51 kg body weight, 140+/-59 days in milk) were used in the study. Cows were randomly assigned to one of two dietary treatments, a high forage:concentrate (HFC, 74:26) or a moderate forage:concentrate (MFC, 56:44) total mixed ration. Cows were fed at 08.00 and 13.00 h and pulse-dosed ruminally at 13.00 h over a 10-min duration with 2% of diet dry matter of SBO. Ruminal pH was recorded continuously. Cows receiving the MFC treatment had lower daily mean ruminal pH and ruminal pH was below 6.0 for a longer duration compared with the HFC treatment (640 vs. 262 min/d, P<0.05). Cows receiving the MFC treatment had a greater reduction (diet by week interaction, P<0.05) in milk fat concentration and yield than cows receiving the HFC treatment (42 vs. 22% and 45 vs. 21%, respectively). Additionally, cows receiving the MFC diet had a greater reduction in milk fat concentration (g/100 g FA) of FA concentration of FA >C16 (17 vs. 9%), trans-10 18:1 (159 vs. 21%) and trans-9, cis-11 conjugated linoleic acid (121 vs. 55%) (P<0.05) compared with cows receiving the HFC diet. This study demonstrated that cows fed the MFC diet had lower ruminal pH and showed a greater rate of milk fat depression when infused with SBO. PMID:20529409

Alzahal, Ousama; Or-Rashid, Mamun M; Greenwood, Sabrina L; McBride, Brian W



Supplementation with Extruded Linseed Cake Affects Concentrations of Conjugated Linoleic Acid and Vaccenic Acid in Goat Milk  

Microsoft Academic Search

The aim of this research was to determine the effect of adding extruded linseed cake to the dry diet of goats on the concentrations of conjugated linoleic acid (CLA) and vaccenic acid (VA) in milk fat. Thirty crossbreed dairy goats were divided into 3 groups. Their diet was supplemented with 0% (control group), 5% (low group), or 10% (high group)

A. Nudda; G. Battacone; M. G. Usai; S. Fancellu; G. Pulina



Response of Milking Cows Fed a High Concentrate, Low Roughage Diet Plus Sodium Bicarbonate, Magnesium Oxide, or Magnesium Hydroxide1  

Microsoft Academic Search

To determine the ability of mineral supplements to elevate depressed milk fat percent, we placed 42 Holstein cows in early to midlactation in seven blocks and assigned each to one of six treatments: 1) control (25% corn silage and alfalfa haylage, 75% concentrate, mostly corn, dry matter); 2) control plus magnesium oxide ground to pass a .425-mm sieve; 3) control

J. W. Thomas; R. S. Emery; J. K. Breaux; J. S. Liesman



Improving Infant Exposure and Health Risk Estimates: Using Serum Data to Predict Polybrominated Diphenyl Ether Concentrations in Breast Milk  

EPA Science Inventory

Women in the United States have breast milk concentrations of polybrominated diphenyl ethers (PBDEs) that are among the highest in the world, leading to concerns over the potential health implications to breastfeeding infants during critical stages of growth and development. Deve...


Effect of supplementation of grazing dairy ewes with a cereal concentrate on animal performance and milk fatty acid profile1  

Microsoft Academic Search

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,

P. Gómez-Cortés; P. Frutos; A. R. Mantecón; M. Juárez; M. A. de la Fuente; G. Hervás



Effect of Intake of Pasture on Concentrations of Conjugated Linoleic Acid in Milk of Lactating Cows1  

Microsoft Academic Search

We examined the effect of intake of fresh pasture on concentrations of conjugated linoleic acid in milk fat. Sixteen Holstein cows were paired and divided into either the control group or the grazing group. The study involved initial, transition, and final peri- ods. During the initial period, all cows consumed a total mixed diet. Cows in the control group were

M. L. Kelly; E. S. Kolver; D. E. Bauman; M. E. Van Amburgh; L. D. Muller



Hot topic: pathway confirmed for the transmission of melamine from feed to cow's milk.  


Eight lactating Holstein cows were randomly allotted to 2 groups in a trial to establish whether a pathway exists for the transmission of melamine from feed to milk. All cows received oat hay ad libitum and 15 kg of concentrate pellets per cow daily. The concentrate pellets contained either melamine-contaminated corn gluten meal of Chinese origin (melamine treatment) or locally produced melamine-free corn gluten meal (control treatment). Cows in the melamine treatment ingested 17.1 g of melamine per day. Cows were milked twice daily, and milk samples were taken once daily during the afternoon milking for melamine and milk component analyses. Melamine appeared in the milk within 8 h after first ingestion of the melamine containing pellets. Melamine concentration reached a maximum of 15.7 mg/kg within 56 h after first ingestion, with an excretion efficiency of approximately 2%. Milk solids and milk urea nitrogen were not affected by treatment. The melamine concentration dropped rapidly after changing all cows back to the control pellets, but melamine only declined to undetectable levels in the milk more than 6 d (152 h) after last ingestion of melamine. Results from the current trial are important to the feed and dairy industries because, until now, any melamine found in milk and milk products was attributed only to the deliberate external addition of melamine to these products, not to adulterated ingredients in animal feeds. PMID:19389962

Cruywagen, C W; Stander, M A; Adonis, M; Calitz, T



How does urea really denature myoglobin?  

NASA Astrophysics Data System (ADS)

This study reports on a model for denaturation of myoglobin by urea for concentrations ranging from 0.1 M to 15 M. The experimental data from quartz crystal microbalance (QCM), circular dichroism (CD) and dilational rheology are examined with respect to a 'structure-breaking effect' of urea on the aqueous phase. Even at urea concentrations >10 M, native conformation of the protein is retained through a restabilization of the hydrophobic association. Our study shows that any proposed denaturation mechanism of large biomolecules requires very high concentrations of urea and the association of urea with protein-water system is based on enhancement of hydrophobic interactions.

Muthuselvi, L.; Miller, Reinhard; Dhathathreyan, A.



Relationship Between Content of Crude Protein in Rations for Dairy Cows and Milk Yield, Concentration of Urea in Milk and Ammonia Emissions  

Microsoft Academic Search

During recent decades, efforts have been made in several countries to diminish the negative environmen- tal influence of dairy production. The main focus has beenonnitrogenandphosphorus.Moderndairyproduc- tion in Western Europe is often based on imported feed- stuffs, mostly protein-rich feeds. In Sweden at least, it is wished that the use of imported feedstuffs in animal production will decrease due to the

B. Frank; C. Swensson



The effect of diets on milk production and composition, and on lactation curves in pastured dairy goats.  


A 2-yr study investigated effects of different levels of concentrate supplementation on milk production, composition, and lactation curves in pastured dairy goats. For both years, 44 Alpine goats (Capra hircus; 55 +/- 11 kg body weight) were randomly allocated to 4 groups. Animals were supplemented with 0.66 (treatments A and B), 0.33 (treatment C), or 0 kg of concentrate (treatment D) per kg of milk over 1.5 kg/d. Mixed vegetative forages were rotationally grazed by the goats (treatments B, C, and D), except that treatment A was confined and fed alfalfa hay. Individual milk production was recorded daily, and milk samples were collected once every 2 wk for the 7-mo period (March to September) and analyzed for fat, protein, lactose, urea-N, nonesterified fatty acids, and allantoin (second year only). Milk yield and composition varied among dietary treatments, with some measures affected by year. Average daily milk yield was lowest for treatment D. The increased level of concentrate supplementation in treatment A led to 22% greater milk yield compared with treatment D. Milk production increased by 1.7 and 0.9 kg for each additional kilogram of concentrate fed per day during the first and second years, respectively. Average peak yield, time of peak yield, and persistency were lower for treatment D than for other treatments. The percentage of milk fat was lower for treatment D than for other treatments. Concentration of milk protein was greater for treatments A and B during the first year, and was higher for treatment C than for other treatments during the second year. Average milk lactose concentration was higher for treatments B and C than for other treatments. However, milk urea-N concentration in treatment A was higher than other treatments. Milk allantoin, used to estimate microbial proteins synthesis, was 20 to 25% greater for treatment A than for other treatments. Averaged across year, plasma urea-N and nonesterified fatty acids concentration were lowest for treatment B. Average organic matter intake was similar among treatments during both years. Ratios of acetate and propionate concentrations for treatment A were lowest among treatments. In conclusion, milk production and composition were affected by the feeding treatment and year. Increased level of nutrition lead to an increase in daily milk yield, peak yield, time of peak yield, and persistency compared with treatment D. Alpine dairy goats grazing on fresh forages without concentrate supplementation can produce milk inexpensively, and response to concentrate supplementation is greater for low quality pasture. PMID:15956322

Min, B R; Hart, S P; Sahlu, T; Satter, L D



Rheological characterisation of age thickening with special reference to milk concentrates.  


Age thickening is a well known phenomenon within the dairy industry, where the apparent viscosity of concentrated dairy solutions increases with storage time under low shear. The objective of the paper is to develop new tools to analyse several aspects of age thickening, including the increases in shear thinning, the degree of thixotropy and the rate of structural build up with time, as well as irreversible structural changes and gelation. The build up of the dispersed phase structure during storage, was captured by a snap shot technique, where concentrated milk samples were stored, and aliquots were taken at periodic intervals and subjected to shear sweep tests to collect flow curves. Rheological modelling using the Herschel-Bulkley model showed an increase in yield stress and consistency, indicating a build up in structure during age thickening. The trend in apparent viscosity with storage time showed two-phases, a slow and steady increase followed by a sharp rise, which could be used to identify the onset of firm gelation. The extrapolated viscosity at infinite shear rate increased with storage time, indicating the build up in irreversible structural components during age thickening. PMID:17214913

Trinh, Binh; Haisman, Derek; Trinh, Khanh Tuoc



High-Concentrate Diets and Polyunsaturated Oils Alter Trans and Conjugated Isomers in Bovine Rumen, Blood, and Milk  

Microsoft Academic Search

Three Holstein cows were fed a high-concentrate diet (65:35 concentrate to forage) supplemented with either 5% sunflower oil (SO), 5% linseed oil (LO), or 2.5% fish oil (FO) to examine effects on biohydrogenation and fatty acid profiles in rumen, blood plasma, and milk. Diets were fed in a 3 × 3 Latin square with 4-wk periods with grass hay as

J. J. Loor; A. Ferlay; A. Ollier; K. Ueda; M. Doreau; Y. Chilliard



Concentration of conjugated linoleic acid in grazing sheep and goat milk fat  

Microsoft Academic Search

The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their lactation period, was examined. Six sheep and six goat representative farms were selected at random and milk samples were taken at monthly intervals for fatty acids profile determination. Sheep and goat nutrition was based on natural grazing and on supplementary feeding during the winter months.

E. Tsiplakou; K. C. Mountzouris; G. Zervas



Trace Element Concentrations in Breast Milk and Sera: Relations With Lactation  

Microsoft Academic Search

Breast milk has unique properties; one is the variability of the compounds in ratio according to the baby's needs for every lactation period. Iron and zinc are essential elements for life. The aim of this study is to determine Fe and Zn levels in plasma and breast milk of mothers through the first 4 months after delivery and to evaluate

Tanju Basarir Ozkan; Neslihan Durmaz; Gulin Erdemir; Yesim Ozarda Ilcol


Effect of corn silage harvest maturity and concentrate type on milk fatty acid composition of dairy cows.  


The variation in maturity at harvest during grain filling has a major effect on the carbohydrate composition (starch:NDF ratio) and fatty acid (FA) content of corn silages, and can alter the FA composition of milk fat in dairy cows. This study evaluated the effect of silage corn (cv. Atrium) harvested and ensiled at targeted DM contents of 300, 340, 380, and 420 g/kg of fresh weight and fed to dairy cows in combination with a highly degradable carbohydrate (HC) or low-degradable carbohydrate concentrate, on the nutrient intake, milk yield, and composition of milk and milk fat. Sixty-four multiparous Holstein-Friesian dairy cows in their first week of lactation were assigned to the 8 dietary treatments according to a randomized complete block design. The 8 dietary treatments consisted of a factorial combination of the 4 corn silages and the 2 concentrates. Corn silages were offered ad libitum as part of a basal forage mixture, whereas the concentrates were given at the rate of 8.5 kg of DM/cow per day during the 15-wk experimental period. Dry matter, crude protein, and energy intakes did not differ across the corn silages. However, the intake of starch increased, and those of NDF and C18:3n-3 decreased with increasing maturation. Milk yield and composition were not different across the corn silages. Yield (kg/d) of milk, protein, and lactose was higher for low-degradable carbohydrate compared with HC concentrate-fed groups. Increasing maturity of corn silages decreased the content of C18:3n-3 and total n-3 and increased the n-6:n-3 ratio in milk fat. Concentrate type significantly altered the composition of all trans FA, except C18:2 trans-9,12. Inclusion of the HC concentrate in the diets increased the contents of all C18:1 trans isomers, C18:2 cis-9,trans-11, and C18:2 trans-10,cis-12 conjugated linoleic acid in milk fat. Milk fat composition was strongly influenced by the stage of lactation (wk 3 to 10). The content of all even short- and medium-chain FA changed with lactation, except C8:0 and C10:0. The content of C12:0, C14:0, and C16:0 and total saturated FA increased and the content of C18:0, C18:1 cis total, and total cis monounsaturated FA decreased with lactation. Maturity of the corn silages at harvest did not affect the production performance of dairy cows, but resulted in a decreased content of C18:3n-3, total n-3, and an increased n-6:n-3 ratio in the milk fat of dairy cows. PMID:22365229

Khan, N A; Tewoldebrhan, T A; Zom, R L G; Cone, J W; Hendriks, W H



Concentrations of toxic heavy metals and trace elements in raw milk of Simmental and Holstein-Friesian cows from organic farm.  


Concentrations of toxic heavy metals (cadmium (Cd), lead (Pb)) and major nutritional and trace elements (Ca, Mg, P, Cu, Fe, Mn, Se, Zn) were analyzed in the milk of Simmental (n?=?20) and Holstein-Friesian (n?=?20) cows from an organic farm. Elements were determined using inductively coupled plasma emission atomic spectrometry. The conducted research showed that the milk of Simmental cows was characterized by the more advantageous mineral composition and lower concentration of noxious heavy metals compared to the milk of Holstein-Friesian cows. In the milk of Simmental cows, significantly lower concentrations of Pb and Cd (P?concentrations of Fe and Mg (P?concentrations of Ca, Mn, and Se were found. In the milk of both breeds, very low Cu concentrations were recorded. The higher-than-recommended concentration of Pb in milk was also found. In the milk of both breeds, the significant positive correlations between concentrations of the following elements were observed: Pb-Cd, Pb-Se, Cd-Se, Cd-Mn, Zn-Cu, Zn-P, Ca-P, Ca-Mg, and Mg-P. The correlations between other elements within each of the analyzed breeds separately were also found. PMID:23572404

Pilarczyk, Renata; Wójcik, Jerzy; Czerniak, Pawe?; Sablik, Piotr; Pilarczyk, Bogumi?a; Tomza-Marciniak, Agnieszka



A comparison of the concentrations of certain chlorinated hydrocarbons and polychlorinated biphenyls in bone marrow and fat tissue of children and their concentrations in breast milk  

SciTech Connect

Chlorinated hydrocarbon (CHC) and polychlorinated biphenyl (PCB) concentrations in the bone marrow of 57 children were compared with the concentrations in adipose tissue of 50 children and the concentrations in breast milk in the Federal Republic of Germany from 1984 to 1991. The concentrations of hexachlorobenzene (HCB), the dichlorodiphenyl-trichlorethane (DDT)-metabolites, and polychlorinated biphenyl (PCB) congeners no. 138 and no. 153 were increased threefold, while the concentrations of several hexachloro-cyclohexane (HCH)-isomers and PCB congener no. 180 were only increased two fold. Because breast feeding is the primary source of CHC and PCB in toddlers and infants we also compared the concentrations in bone marrow of children with the concentrations in breast milk and found approximately fourfold higher concentrations for the most highly chlorinated PCB congener no. 180, but only threefold higher concentrations for PCB 138 and 153 and the DDT-metabolites. The concentrations of {beta}-HCH and HCB were only slightly higher in bone marrow. 15 refs., 2 figs.

Scheele, J.; Teufel, M.; Niessen, K.H. [Univ. of Heidelberg, Mannheim (Germany)



Effect of ethanol in feed on milk flavor and chemical composition.  


A crossover study was performed using 24 dairy cows to investigate whether pure ethanol in concentrations that could be found in well-fermented silages influenced milk composition or flavor. Cows were fed a standard ration of well-fermented grass silage for ad libitum intake and high moisture barley and a protein concentrate in restricted amounts. A daily dose of ethanol (600 g) was divided into three meals/d and fed with grass silage. When cows received ethanol, milk yields decreased slightly, but milk fat and protein concentrations increased so that energy-corrected milk yield increased by 0.9 kg/d. Milk concentrations of lactose and urea decreased, concentrations of ethanol and acetone increased, concentrations of free fatty acids increased slightly, and alpha-tocopherol concentrations were unaffected. The proportion of palmitic acid in milk fat increased, and the proportion of unsaturated acids decreased. Organoleptic milk quality was reduced because of an increase in milk tainted by feed flavors. The off-flavor could not be attributed solely to the ethanol transmitted to the milk. Precautions should be taken to avoid extensive production of ethanol during fermentation of grass silage and other feeds that are to be fed to dairy cows. PMID:10068963

Randby, A T; Selmer-Olsen, I; Baevre, L



Effect of safflower oil, flaxseed oil, monensin, and vitamin E on concentration of conjugated linoleic acid in bovine milk fat.  


Conjugated linoleic acid (CLA) refers to a mixture of conjugated octadecadienoic acids of predominantly ruminant origin. The main isomer in bovine milk fat is the cis-9, trans-11 CLA. Interest in CLA increased after the discovery of its health-promoting properties, including potent anticarcinogenic activity. Two experiments were conducted to evaluate dietary strategies aimed at increasing the concentration of CLA in bovine milk fat. Both experiments were organized as a randomized complete block design with a repeated measures treatment structure. In Experiment 1, 28 Holstein cows received either a control diet or one of 3 treatments for a period of 2 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a dry matter (DM) basis, fed as a total mixed ration (TMR). The concentrate was partially replaced in the treatment groups with 24 ppm of monensin (MON), 6% of DM safflower oil (SAFF), or 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M). Average cis-9, trans-11 CLA levels in milk fat after 2 wk of feeding were 0.45, 0.52, 3.36, and 5.15% of total fatty acids for control, MON, SAFF, and SAFF/M, respectively. In Experiment 2, 62 Holstein cows received either a control diet or one of 5 treatment diets for a period of 9 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a DM basis, fed as a TMR. The concentrate was partially replaced in the treatment groups with 6% of DM safflower oil (SAFF), 6% of DM safflower oil plus 150 IU of vitamin E/kg of DM (SAFF/E), 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M), 6% of DM safflower oil plus 24 ppm of monensin plus 150 IU of vitamin E/kg of DM (SAFF/ME), or 6% of DM flaxseed oil plus 150 IU of vitamin E/kg of DM (FLAX/E). Average cis-9, trans-11 CLA levels during the treatment period were 0.68, 4.12, 3.48, 4.55, 4.75, and 2.80% of total fatty acids for control, SAFF, SAFF/E, SAFF/M, SAFF/ME, and FLAX/E, respectively. The combination of safflower oil with monensin was particularly effective at increasing milk fat CLA. The addition of vitamin E to the diet partially prevented the depression in milk fat associated with oilseed feeding, but had no significant effect on the concentration of CLA in milk. PMID:16428641

Bell, J A; Griinari, J M; Kennelly, J J



Aquaporin-9 and urea transporter-A gene deletions affect urea transmembrane passage in murine hepatocytes.  


In mammals, the majority of nitrogen from protein degradation is disposed of as urea. Several studies have partly characterized expression of urea transporters (UTs) in hepatocytes, where urea is produced. Nevertheless, the contribution of these proteins to hepatocyte urea permeability (P(urea)) and their role in liver physiology remains unknown. The purpose of this study was to biophysically examine hepatocyte urea transport. We hypothesized that the water, glycerol, and urea channel aquaporin-9 (AQP9) is involved in hepatocyte urea release. Stopped-flow light-scattering measurements determined that the urea channel inhibitors phloretin and dimethylurea reduced urea permeability of hepatocyte basolateral membranes by 70 and 40%, respectively. In basolateral membranes isolated from AQP9(-/-) and UT-A1/3(-/-) single-knockout and AQP9(-/-):UT-A1/3(-/-) double-knockout mice, P(urea) was decreased by 30, 40, and 76%, respectively, compared with AQP9(+/-):UT-A1/3(+/-) mice. However, expression analysis by RT-PCR did not identify known UT-A transcripts in liver. High-protein diet followed by 24-h fasting affected the concentrations of urea and ammonium ions in AQP9(-/-) mouse liver and plasma without generating an apparent tissue-to-plasma urea gradient. We conclude that AQP9 and unidentified UT-A urea channels constitute primary but redundant urea facilitators in murine hepatocytes. PMID:23042941

Jelen, Sabina; Gena, Patrizia; Lebeck, Janne; Rojek, Aleksandra; Praetorius, Jeppe; Frřkiaer, Jřrgen; Fenton, Robert A; Nielsen, Sřren; Calamita, Giuseppe; Rützler, Michael



Boron Concentrations in Milk from Mothers of Exclusively Breast-Fed Healthy Full-Term Infants Are Stable during the First Four Months of Lactation1,2  

Microsoft Academic Search

Because boron is a bioactive element that satisfies several of the criteria for essentiality in humans, the aim of the present work was to determine the profile of boron metabolism in human milk during the first 4 mo of lactation. The concentration of boron and other minerals was determined in archived milk collected (1980-84) 1 time\\/mo for 4 mo from

Curtiss D. Hunt; Nancy F. Butte; LuAnn K. Johnson


Modified Milk Fat Reduces Plasma Triacylglycerol Concentrations: Health and Disease Effects  

Microsoft Academic Search

\\u000a •?Milk fat has a unique fatty acid profile and is a very complex mixture of triglycerides and is generally considered a cholesterol-raising\\u000a ingredient, as it contains a large proportion of saturated fatty acids and moderate amount of cholesterol.\\u000a \\u000a \\u000a •?Various techniques are currently under active development to improve the nutritional value of milk fat, and counteract its\\u000a adverse effect on plasma

Hélčne Jacques; Nadine Leblanc; Nathalie Bergeron


Microfiltration of Buttermilk and Washed Cream Buttermilk for Concentration of Milk Fat Globule Membrane Components  

Microsoft Academic Search

Buttermilk, the by-product from butter manufacture, hasgainedmuchattentionlatelybecauseoftheapplica- tion potentialof its milkfat globulemembrane (MFGM) components as health ingredients. Microfiltration (MF) has been studied for buttermilk fractionation because ofitsabilitytoseparateparticlesfromdissolvedsolutes. However, the presence in this by-product of skim milk solids, especially casein micelles, restricts concentra- tion of MFGM.The use of cream washedwith skim milk ultrafiltrate to produce buttermilk with lower casein content was

P. Morin; M. Britten; R. Jiménez-Flores; Y. Pouliot



A Sustainable Alternative to a Breast Milk Monitoring Program: Using NHANES Serum Data to Estimate Breast Milk PBDE Concentrations  

EPA Science Inventory

Polybrominated diphenyl ethers (PBDEs) are high-production-volume chemicals that have been widely used as flame retardants in a variety of consumer products. PBDE concentrations in the environment, wildlife, and humans have been increasing for several decades. Concentrations in t...


Effects of fat concentration of a high-protein milk replacer on calf performance.  


The hypothesis was that calves fed high-fat milk replacers (MR) would have reduced starter intake, digestibility, and average daily gain (ADG). Forty-eight Holstein calves (initially 42.4 +/- 1.5 kg of body weight, 2 to 3 d of age; 12 calves/treatment) were fed 0.66 kg dry matter (DM) of MR per calf daily that contained 14, 17, 20, or 23% fat. This MR had crude protein (CP) to metabolizable energy (ME) ratios ranging from 51.6 to 56.7 g of CP/Mcal of ME, which were above and below a previously determined optimum. Calves were weaned at 28 d; postweaning measurements were continued to d 56. A 20% CP starter and water were fed ad libitum all 56 d of the trial. Measurements of digestion were made using chromic oxide as a marker in the MR and starter from fecal samples collected on d 19 to 23 from 4 calves/treatment. Selected serum constituents were measured on d 21. Calves were housed individually in pens bedded with straw within a naturally ventilated barn with no added heat. The average barn temperature was 2 degrees C. Data were analyzed as a completely randomized design using polynomial contrasts to separate differences in the means. Preweaning apparent digestibility of DM, organic matter, fat, nonfiber carbohydrates, Ca, and P and serum amylase concentration were linearly reduced as fat increased from 14 to 23%. Preweaning starter intake responded quadratically to fat, being lowest at 14 and 23% fat. A reduction in digestibility and starter intake contributed to less ADG at the higher fat concentrations in the MR. A 27% CP, 17% fat MR with 55 g of CP/Mcal of ME maximized preweaning ADG when fat concentration was varied to obtain various CP to ME ratios in the MR. Additionally, a 27% CP, 20% fat MR with 53 g of CP/Mcal of ME supported overall ADG similar to calves fed the 17% fat MR but preweaning digestion measurements and serum amylase concentrations were less than in calves fed the 17% fat MR. PMID:19762833

Hill, T M; Bateman, H G; Aldrich, J M; Schlotterbeck, R L



Temporal trends in dioxin, furan and polychlorinated biphenyl concentrations in bovine milk from farms adjacent to industrial and chemical installations over a 15 year period.  


The concentrations of polychlorinated dibenzo-p-dioxins, furans and polychlorinated biphenyls (PCBs) were measured in pooled bovine milk samples collected between 1991 and 2005 in County Cork, Ireland. The pooled samples were of bulk-tank milk collected from farms adjacent to industrial, chemical and pharmaceutical installations (target milk) or from rural farms distant from industrial activity (control milk). Comparing data between the first and last 3-year periods of the study revealed a 62% decrease in the mean total dioxin concentration in target milk from 1.58 to 0.60pg toxic equivalents (TEQ)/g fat. On the same basis the dioxin-like PCB concentration in target milk decreased by 80% over the study period (from 0.95pg to 0.19pg TEQ/g fat). The mean 'marker' PCB concentration in target milk from 1991 to 1993 inclusive was 3359pg/g fat. This value decreased by 75% to a mean of 849pg/g fat for the years 2003-2005 inclusive. The results of this study are consistent with low background dietary/environmental PCB contamination in both target and control herds. The total dioxin concentrations in all samples were well below the maximum tolerable limits permitted for marketable milk. The decrease in the total dioxin concentration in target and control milk samples over the study period was chiefly due to decreases in the concentration of dioxin-like PCBs, consistent with significant reductions in the concentration of PCBs in the dairy cow diet over the 15 year study period. PMID:21470881

O'Donovan, James V; O'Farrell, Kevin J; O'Mahony, Pat; Buckley, James F



Milk Fatty Acid Composition of Cows Fed a Total Mixed Ration or Pasture Plus Concentrates Replacing Corn with Fat  

Microsoft Academic Search

Thirty-one Holstein cows (six ruminally cannulated) were used to evaluate milk fatty acids (FA) composition and conjugated linoleic acid (CLA) content on three dietary treatments: 1) total mixed rations (TMR), 2) pasture (Avena sativa L.) plus 6.7 kg DM\\/d of corn- based concentrate (PCorn), and 3) pasture plus PCorn with 0.8 kg DM\\/d of Ca salts of unsaturated FA replac-

G. F. Schroeder; J. E. Delahoy; I. Vidaurreta; F. Bargo; G. A. Gagliostro; L. D. Muller



Increasing the concentrations of beneficial polyunsaturated fatty acids in milk produced by dairy cows in high-forage systems  

Microsoft Academic Search

There is considerable interest in altering the fatty acid composition of milk with the overall aim of improving the long-term health of consumers. Important targets include reducing the amounts of medium-chain saturated fatty acids, enhancing cis-9 18:1 to reduce cardiovascular risk, as well as increasing concentrations of trans-11 18:1 and cis-9, trans-11 18:2 which have been shown to exert anti-carcinogenic

R. J. Dewhurst; K. J. Shingfield; M. R. F. Lee; N. D. Scollan



Effects of Clover-Grass Silages and Concentrate Supplementation on the Content of Phytoestrogens in Dairy Cow Milk  

Microsoft Academic Search

A2 × 2 factorial continuous experiment was con- ductedwith28NorwegianReddairycowsinearlylacta- tion to compare milk content of phytoestrogens when feeding ad libitum white clover (WCS) or red clover (RCS) grass silages prepared from the second and third cutwithoutandwith10kg\\/dsupplementationofastan- dard concentrate. The cows were offered either RCS or WCS for 88 d (period 1) and thereafter a mixed red clover-whiteclover-grasssilagefor48d(period2).Total dry matter intake

H. Steinshamn; S. Purup; E. Thuen; J. Hansen-Mřller



Effect of increasing concentrations of zinc on the absorption of iron from iron-fortified milk.  


The cofortification of milk with iron (Fe) and zinc (Zn) is a strategy used to prevent these deficiencies during childhood. Given that Zn can negatively interact with iron in aqueous solutions, the objective of the present study was to determine the effect of Zn on Fe absorption of milk fortified with Fe and Zn. Twenty-eight women between 33 and 47 years of age, with contraception and a negative pregnancy test, participated in one of two absorption studies. They received on four different days, after an overnight fast, 200 mL of milk (26 % fat) fortified with 10 mg Fe/L, as (A) ferrous sulfate, or the same milk but with graded doses of added Zn, as Zn sulfate of (B) 5, (C) 10, and (D) 20 mg/L (study 1, n?=?15). In study 2 (n?=?13), subjects received the same milk formulations, but these were also fortified with ascorbic acid (70 mg/L). Milk was labeled with radioisotopes ??Fe or ??Fe, and the absorption of iron was measured by erythrocyte incorporation of radioactive Fe. The geometric mean and range of ±1 SD of Fe absorption in study 1 were as follows: formula A?=?6.0 % (2.8-13.0 %); B?=?6.7 % (3.3-13.6 %); C?=?5.4 % (2.2-13.2 %); and D?=?5.2 % (2.8-10.0 %) (ANOVA for repeated measures, not significant). For study 2, data are as follows: 8.2 % (3.6-18.7 %); B?=?6.4 % (2.5-16.4 %); C?=?7.7 % (3.2-18.9 %); and D?=?5.2 (1.8-14.8 %) (ANOVA for repeated measures, not significant). In conclusion, according to the results from this study, it appears that the addition of zinc up to 20 mg/L does not significantly inhibit iron absorption from milk fortified with 10 mg/L of iron. PMID:22760642

Olivares, Manuel; Wiedeman, Alejandra; Bolívar, Lorena; López de Romańa, Daniel; Pizarro, Fernando



The Effects of Dietary Soybean Versus Skim Milk Protein on Plasma and Hepatic Concentrations of Zinc in Veal Calves  

Microsoft Academic Search

We assessed the zinc status of veal calves that were fed milk replacers containing either skim milk protein as the sole source of protein or a mixture of skim milk protein and soybean protein. After the milk replacers had been fed for 26 wk, mean body weight gain was 3 kg lower for calves fed the skim milk plus soybean

C. Xu; T. Wensing; A. C. Beynen



Spectroscopic characterization of urea aqueous solutions: experimental phase diagram of the urea-water binary system.  


Raman spectroscopy was used to analyze mixtures of urea and water in order to identify the influence of the urea concentration on the solution's freezing point. Our approach consisted in the analysis of urea aqueous solutions and the determination of their phase transitions at low temperatures. Hence, Raman spectra of these solutions were acquired in a -30 to 10 °C temperature range. This enabled us to build the experimental phase diagram of the urea-water binary system. PMID:24067578

Durickovic, Ivana; Thiébaud, Laura; Bourson, Patrice; Kauffmann, Thomas; Marchetti, Mario



Relation of Lake Ontario fish consumption, lifetime lactation, and parity to breast milk polychlorobiphenyl and pesticide concentrations  

SciTech Connect

Lactating female members and spouses of male members of the New York State Angler Cohort who agreed to provide breast milk samples were the subjects of this study. Milk samples were analyzed for 77 polychlorinated biphenyls (PCB) congeners, 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (DDE), a metabolite of dichlorodiphenyltrichloroethane (DDT), hexachlorobenzene (HCB), and 1,1a,2,2,3,3a,4,5,5,5a,5b,6-dodecachlorooctahydro-1,3,4-methano-1H-cyclobuta[cd]pentalene (Mirex). The percentage of samples with quantifiable levels, above the limit of detection (LOD), varied among the individual congeners from 10 to 100%. Nine PCB congeners and DDE were found in all of the 100 samples analyzed. Fish eaters had a significantly higher level of several major PCB congeners with congeners 153 and 138 being 1.36 and 1.34 times higher, respectively. PCB and DDE concentrations, expressed on a lipid basis, varied inversely with parity. The total number of months of lifetime lactation varied inversely with the total PCB concentration in breast milk.

Kostyniak, P.J.; Stinson, C.; Hreizerstein, H.B.; Vena, J.; Buck, G.; Mendola, P. [State Univ. of New York, Buffalo, NY (United States)



Variation in Flavonolignan Concentration of Milk Thistle (Silybum marianum) Fruits Grown in Iran  

Microsoft Academic Search

This study was conducted to analyze the genetic variation of silymarin and the corresponding flavonolignans in the fruit (achenes) of 32 ecotypes of milk thistle, Silybum marianum (L.) Gaertner, collected from the north, northwest, south, and southwest of Iran and two improved commercial varieties, one from England (CN Seeds, Ltd., Ely, United Kingdom) and one from Hungary (Budakalaszi, Budakalasz). A

Majid Shokrpour; Seyed Abolghasem Mohammadi; Mohammad Moghaddam; Seyed Ali Ziai; Aziz Javanshir



Milk Cholesterol Concentration in Sows Selected for Three Generations for High or Low Serum Cholesterol'12  

Microsoft Academic Search

Female crossbred swine (Chester White x Landrace x Large White x Yorkshire) selected for three generations for low (L, n = 24) or high (H, n = 26) serum cholesterol at 8 wk of age were milked at d 20 or 21 of their first lactation to measure cholesterol, fat, lactose, protein, and ash concentra- tions. A contemporary, unselected control

Milton M. Kandeh; Wilson G. Pond; Lawrence D. Young



Residual concentrations of the flukicidal compound triclabendazole in dairy cows’ milk and cheese  

Microsoft Academic Search

Triclabendazole (TCBZ) is a flukicidal halogenated benzimidazole compound extensively used in veterinary medicine. Liver fluke control in lactating dairy cattle is difficult because treatment should be implemented only during the dry period to avoid milk residues. However, control in endemic areas is usually implemented as regular treatments three to four times a year, even during the lactating period. Thus, information

F. Imperiale; P. Ortiz; M. Cabrera; C. Farias; J. M. Sallovitz; S. Iezzi; J. Pérez; L. Alvarez; C. Lanusse



Ontogeny of rabbit proximal tubule urea permeability.  


Urea transport in the proximal tubule is passive and is dependent on the epithelial permeability. The present study examined the maturation of urea permeability (P(urea)) in in vitro perfused proximal convoluted tubules (PCT) and basolateral membrane vesicles (BLMV) from rabbit renal cortex. Urea transport was lower in neonatal than adult PCT at both 37 and 25 degrees C. The PCT P(urea) was also lower in the neonates than the adults (37 degrees C: 45.4 +/- 10.8 vs. 88.5 +/- 15.2 x 10(-6) cm/s, P < 0.05; 25 degrees C: 28.5 +/- 6.9 vs. 55.3 +/- 10.4 x 10(-6) cm/s; P < 0.05). The activation energy for PCT P(urea) was not different between the neonatal and adult groups. BLMV P(urea) was determined by measuring vesicle shrinkage, due to efflux of urea, using a stop-flow instrument. Neonatal BLMV P(urea) was not different from adult BLMV P(urea) at 37 degrees C [1.14 +/- 0.05 x 10(-6) vs. 1.25 +/- 0.05 x 10(-6) cm/s; P = not significant (NS)] or 25 degrees C (0.94 +/- 0.06 vs. 1.05 +/- 0.10 x 10(-6) cm/s; P = NS). There was no effect of 250 microM phloretin, an inhibitor of the urea transporter, on P(urea) in either adult or neonatal BLMV. The activation energy for urea diffusion was also identical in the neonatal and adult BLMV. These findings in the BLMV are in contrast to the brush-border membrane vesicles (BBMV) where we have previously demonstrated that urea transport is lower in the neonate than the adult. Urea transport is lower in the neonatal proximal tubule than the adult. This is due to a lower rate of apical membrane urea transport, whereas basolateral urea transport is the same in neonates and adults. The lower P(urea) in neonatal proximal tubules may play a role in overall urea excretion and in developing and maintaining a high medullary urea concentration and thus in the ability to concentrate the urine during renal maturation. PMID:11353675

Quigley, R; Lisec, A; Baum, M




SciTech Connect

Urea SCR is currently the only proven NOX aftertreatment for diesel engines - high NOX reduction possible - some SCR catalyst systems are robust against fuel sulfur - durability has been demonstrated - many systems in the field - long history in other markets - Major limitations to acceptance - distribution of urea solution to end user - ensuring that urea solution is added to vehicle.

Bunting, Bruce G.



Urea transport in the kidney.  


Urea transport proteins were initially proposed to exist in the kidney in the late 1980s when studies of urea permeability revealed values in excess of those predicted by simple lipid-phase diffusion and paracellular transport. Less than a decade later, the first urea transporter was cloned. Currently, the SLC14A family of urea transporters contains two major subgroups: SLC14A1, the UT-B urea transporter originally isolated from erythrocytes; and SLC14A2, the UT-A group with six distinct isoforms described to date. In the kidney, UT-A1 and UT-A3 are found in the inner medullary collecting duct; UT-A2 is located in the thin descending limb, and UT-B is located primarily in the descending vasa recta; all are glycoproteins. These transporters are crucial to the kidney's ability to concentrate urine. UT-A1 and UT-A3 are acutely regulated by vasopressin. UT-A1 has also been shown to be regulated by hypertonicity, angiotensin II, and oxytocin. Acute regulation of these transporters is through phosphorylation. Both UT-A1 and UT-A3 rapidly accumulate in the plasma membrane in response to stimulation by vasopressin or hypertonicity. Long-term regulation involves altering protein abundance in response to changes in hydration status, low protein diets, adrenal steroids, sustained diuresis, or antidiuresis. Urea transporters have been studied using animal models of disease including diabetes mellitus, lithium intoxication, hypertension, and nephrotoxic drug responses. Exciting new animal models are being developed to study these transporters and search for active urea transporters. Here we introduce urea and describe the current knowledge of the urea transporter proteins, their regulation, and their role in the kidney. PMID:23737200

Klein, Janet D; Blount, Mitsi A; Sands, Jeff M



Human Utilization of Urea Nitrogen in Low Calorie Diets  

Microsoft Academic Search

To evaluate the role of calorie intake on the ability of nonprotein nitrogen to substitute for part of a high biological value protein, urea was added to the low caloric milk diets of five obese women during periods of negative nitro gen balance. In five studies, negative nitrogen balance was induced by decreasing milk nitrogen intake to 3.7 g\\/day and



Effect of synchronization of follicle-wave emergence with estradiol and progesterone and superstimulation with follicle-stimulating hormone on milk estrogen concentrations in dairy cattle  

PubMed Central

Very little is known about the effects of hormonal synchronization of follicle waves and superovulation on the estrogen content of a cow’s milk. The objective of this study was to determine the effect in dairy cows of synchronization with estradiol-17? (E2) and progesterone (P4) on milk E2 concentrations and to compare these levels with those achieved during superstimulation for 4 d with porcine follicle-stimulating hormone (FSH). The milk E2 concentrations were raised significantly above pretreatment levels (P < 0.05) for 2 d after synchronization, the mean peak being 40.2 ± 18.5 (standard error) pg/mL and the pretreatment mean 1.5 ± 0.5 pg/mL. The mean peak E2 concentration during ovarian stimulation was 4.4 ± 0.7 pg/mL. The mean E2 concentration was significantly higher (P < 0.05) after synchronization than during superstimulation for the 1st milking after synchronization but not subsequent milkings. The milk estrone concentrations were above pretreatment levels for 1 d after synchronization and were not different from those observed during superstimulation.

de Souza, Lucilene B.; Dupras, Raynald; Mills, Louis; Chorfi, Younes; Price, Christopher A.



The effect of dietary iodine supplementation in dairy goats on milk production traits and milk iodine content.  


Dairy products offer an important source of iodine for humans, particularly infants and children. An adequate iodine content in the diet of lactating animals must guarantee a suitable milk iodine concentration. In this experiment, the effects of iodine supplementation of dairy goat diets on the iodine concentration, milk yield, and milk composition of goat milk were studied. Thirty crossbred dairy goats of the Sarda population were divided into 3 groups supplemented with 0 (control group), 0.45 (group 1), or 0.90 (group 2) mg of KI/d per goat. The dose of KI (76.5% of iodine) was dissolved in water and orally administered with a syringe every day for 10 wk. Mean milk iodine concentrations were 60.1 +/- 50.5, 78.8 +/- 55.4, and 130.2 +/- 62.0 microg/L (mean +/- SD) in the control group, group 1, and group 2, respectively. The extent of iodine enrichment in milk was approximately 31% in group 1 and 117% in group 2 compared with the control group. Milk yield was not influenced by KI supplementation and averaged 1,229, 1,227, and 1,179 g/d in groups 0, 1, and 2, respectively. Milk urea nitrogen concentration was significantly lower in the KI-supplemented groups (32 and 33 mg/dL in groups 1 and 2, respectively) than in the control group (37 mg/dL). Iodine supplementation of dairy goat diets can increase milk iodine content without adverse effects on milk production traits. PMID:19762831

Nudda, A; Battacone, G; Decandia, M; Acciaro, M; Aghini-Lombardi, F; Frigeri, M; Pulina, G



A perfusion study of the handling of urea and urea analogues by the gills of the dogfish shark (Squalus acanthias)  

PubMed Central

The branchial mechanism of urea retention in elasmobranchs was investigated using an in vitro isolated-perfused head preparation, as well as in vivo samples, in the spiny dogfish shark. Both in vivo and in control saline perfusions containing 350 mmol L?1 urea, calculated intracellular urea concentrations in gill epithelial cells were close to extracellular concentrations. Urea efflux to the external water fell only non-significantly, and calculated gill intracellular urea concentration did not change when perfusate urea concentration was reduced from 350 to 175 mmol?L?1 with osmotic compensation by 175 mmol L?1 mannitol. However, when the urea analogues thiourea or acetamide were present in the perfusate at concentrations equimolar (175 mmol L?1) to those of urea (175 mmol L?1), urea efflux rates were increased 4-fold and 6.5-fold respectively, and calculated gill intracellular urea concentrations were depressed by about 55%. Analogue efflux rates were similar to urea efflux rates. Previous studies have argued that either the basolateral or apical membranes provided the limiting permeability barrier, and/or that a back-transporter on the basolateral membranes of gill cells is responsible for urea retention. The present results provide new evidence that the apical membrane is the limiting factor in maintaining gill urea impermeability, and raise the prospect that a urea back-transporter, which can be competitively inhibited by thiourea and acetamide, operates at the apical membrane.

Liew, Hon Jung; De Boeck, Gudrun; Walsh, Patrick J.



Nutrient demand interacts with grass maturity to affect milk fat concentration and digestion responses in dairy cows.  


Effects of grass maturity on dry matter intake (DMI), milk production, ruminal fermentation and pool sizes, digestion and passage kinetics, and chewing activity and the relationship of these effects with preliminary DMI (pDMI) were evaluated using 13 ruminally and duodenally cannulated Holstein cows in a crossover design with a 14-d preliminary period and two 18-d treatment periods. During the preliminary period, pDMI of individual cows ranged from 23.5 to 28.2 kg/d (mean=26.1 kg/d) and 3.5% fat-corrected milk (FCM) yield ranged from 30.8 to 57.2 kg/d (mean=43.7 kg/d). Experimental treatments were diets containing orchardgrass silage harvested either (1) early-cut, less mature (EC) or (2) late-cut, more mature (LC) as the sole forage. Early- and late-cut orchardgrass contained 44.9 and 54.4% neutral detergent fiber (NDF) and 20.1 and 15.3% crude protein, respectively. Forage:concentrate ratio was 58:42 and 46:54 for EC and LC, respectively; both diets contained approximately 25% forage NDF and 30% total NDF. Preliminary DMI, an index of nutrient demand, was determined during the last 4d of the preliminary period when cows were fed a common diet and used as a covariate. Main effects of grass maturity and their interaction with pDMI were tested by ANOVA. The EC diet decreased milk yield and increased milk fat concentration compared with the LC diet. Grass maturity and its interaction with pDMI did not affect FCM yield, DMI, rumen pH, or microbial efficiency. The EC diet increased rates of ruminal digestion of potentially digestible NDF and passage of indigestible NDF (iNDF) compared with the LC diet. The lower concentration and faster passage rate of iNDF for EC resulted in lower rumen pools of iNDF, total NDF, organic matter, and dry matter for EC than LC. Ruminal passage rates of potentially digestible NDF and starch were related to level of intake (quadratic and linear interactions, respectively) and subsequently affected ruminal digestibility of these nutrients. The EC diet decreased eating, ruminating, and total chewing time per unit of forage NDF intake compared with the LC diet. When grass silage was the only source of forage in the diet, cows supplemented with additional concentrate to account for decreasing protein and increasing fiber concentrations associated with more mature grass had similar feed intake and produced similar FCM yields as cows fed less mature grass. PMID:22916919

Kammes, K L; Allen, M S



The effect of long term under- and over-feeding of sheep on milk and plasma fatty acid profiles and on insulin and leptin concentrations.  


Since sheep's milk is mainly used for cheese making and milk chemical composition and fatty acids (FA) profile affect cheese yield and quality, the objective of this study was to determine the effects of different feeding levels on milk chemical composition and FA profile, as well as on plasma FA profile, and on insulin and leptin concentrations. Twenty-four sheep were assigned to three homogeneous sub-groups. Throughout the experimental period each group was fed the same diet but in quantities which met 70% (under-feeding), 100% (control) and 130% (over-feeding) of their respective energy and crude protein requirements. The results showed that the underfed sheep had higher milk fat content compared with overfed. In blood plasma the concentrations of C18:0 and C18:1 in the underfed sheep were significantly higher compared with control and overfed sheep. The concentrations of leptin and insulin were significantly higher in overfed compared with underfed sheep. Underfeeding reduced the concentrations of short chain FA (SCFA) and medium chain FA (MCFA) and increased that of C18:0 and mono unsaturated FA (MUFA) in sheep milk fat compared with controls and overfed. The concentrations of C18:0, long chain FA (LCFA) and monounsaturated FA (MUFA) in milk were significantly higher and those of SCFA, MCFA and saturated FA (SFA) significantly lower in the underfed compared with the overfed sheep. In conclusion, long term under- and over-feeding affected the sheep milk chemical composition and FA profile which consequently has an impact on milk products yield (cheese and yogurt) and quality (human health). PMID:22341044

Tsiplakou, Eleni; Chadio, Stella; Zervas, George



Impact 9 of Low Concentration Factor Microfiltration on Milk Component Recovery and Cheddar Cheese Yield1  

Microsoft Academic Search

The effect of microfiltration (MF) on the composition of Cheddar cheese, fat, crude protein (CP), calcium, total solids recovery, and Cheddar cheese yield effi- ciency (i.e., composition adjusted yield divided by theo- retical yield) was determined. Raw skim milk was mi- crofiltered twofold using a 0.1-µm ceramic membrane at 50°C. Four vats of cheese were made in one day using

M. Neocleous; D. M. Barbano; M. A. Rudan



Urea metabolism in plants.  


Urea is a plant metabolite derived either from root uptake or from catabolism of arginine by arginase. In agriculture, urea is intensively used as a nitrogen fertilizer. Urea nitrogen enters the plant either directly, or in the form of ammonium or nitrate after urea degradation by soil microbes. In recent years various molecular players of plant urea metabolism have been investigated: active and passive urea transporters, the nickel metalloenzyme urease catalyzing the hydrolysis of urea, and three urease accessory proteins involved in the complex activation of urease. The degradation of ureides derived from purine breakdown has long been discussed as a possible additional metabolic source for urea, but an enzymatic route for the complete hydrolysis of ureides without a urea intermediate has recently been described for Arabidopsis thaliana. This review focuses on the proteins involved in plant urea metabolism and the metabolic sources of urea but also addresses open questions regarding plant urea metabolism in a physiological and agricultural context. The contribution of plant urea uptake and metabolism to fertilizer urea usage in crop production is still not investigated although globally more than half of all nitrogen fertilizer is applied to crops in the form of urea. Nitrogen use efficiency in crop production is generally well below 50% resulting in economical losses and creating ecological problems like groundwater pollution and emission of nitric oxides that can damage the ozone layer and function as greenhouse gasses. Biotechnological approaches to improve fertilizer urea usage bear the potential to increase crop nitrogen use efficiency. PMID:21421389

Witte, Claus-Peter



Methylmercury exposure during lactation: Milk concentration and tissue uptake of mercury in the neonatal rat  

SciTech Connect

In recent years toxicological interest in mercury has predominantly been focused on the effects of prenatal exposure to methylmercury on the physical and mental development of children. Thus, there has been a general concern to limit the exposure of pregnant women to methylmercury. Much less attention has been paid to postnatal exposure to mercury. However, there is also a possibility of elevated mercury exposure in the newborn due to exposure via breast milk. There is a lack of data from both humans and animals on lactational transfer of many metals. However, metabolic evidence suggests that during the neonatal period the infant is sensitive to effects of these compounds. Thus, the gastrointestinal absorption and the retention of metals is higher during this period than adult life. In the present study the dose-dependent transfer of mercury into milk was studied in lactating rats treated with methyl-mercury. The uptake of mercury in tissues and blood was followed in the offspring exposed via milk.

Sundberg, J.; Oskarsson, A.; Albanus, L. (National Food Administration, Uppsala (Sweden))



Lead concentrations in blood and milk from periparturient dairy heifers seven months after an episode of acute lead toxicosis  

SciTech Connect

In September 1988, 100 of 300 yearling dairy heifers developed blindness, tachypnea, foaming at the mouth, chewing, and facial fasciculations. Twenty-five animals died. Lead toxicosis was diagnosed based on the clinical signs and the presence of excessive concentrations of lead in whole blood, liver, kidney, and rumen contents of affected animals. The source of the lead was sudan grass silage that had been contaminated by soil that contained up to 77,000 mg/kg of lead. Lead concentrations were determined approximately 7 months after the acute episode of lead toxicosis. Whole blood and milk samples were obtained from heifers and a group of control cows 2 weeks prior to (blood only), at the time of, and 2 and 4 weeks after freshening. No lead was found in any of the milk samples (detection limit = 0.055 mg/liter). Animals that had been severely affected by lead toxicosis experienced a transient increase in whole blood lead concentrations at freshening that was not high enough to be considered toxic. No similar increases in blood lead were observed for control cows or heifers that had experienced milder toxicosis. These findings suggest that at parturition lead is mobilized into the blood of cattle previously exposed to excessive lead.

Galey, F.D.; Slenning, B.D.; Anderson, M.L.; Breneman, P.C.; Littlefield, E.S.; Melton, L.A.; Tracy, M.L. (California Veterinary Diagnostic Laboratory System-Toxicology Laboratory, University of California, Davis (USA))



White or red clover-grass silage in organic dairy milk production: Grassland productivity and milk production responses with different levels of concentrate  

Microsoft Academic Search

Red (RC) or white (WC) clover were grown in mixture with grasses, ensiled and offered to dairy cows in early lactation over two successive years (48 cows per year) to compare grassland yield, feed intake, milk production and milk quality. The crops were ensiled in round bales and proportional mixtures of the second and third cut prepared each year were

Hĺvard Steinshamn; Erling Thuen



Predicting cutting and clotting time of coagulating goat's milk using diffuse reflectance: effect of pH, temperature and enzyme concentration  

Microsoft Academic Search

A diffuse reflectance sensor, which used optical fibres and near-infrared radiation (NIR) at 880nm, was used to monitor goat's milk coagulation. A randomised block design replicated three times was utilized to test the effects of pH, temperature and enzyme concentration on diffuse reflectance parameters. Milk pH was adjusted to three levels (5.5, 6.0 and 6.5) and coagulated at three different

M Castillo; F. A Payne; C. L Hicks; M. B Lopez



Production performance and milk composition of grazing dairy cows fed pelleted or non-pelleted concentrates treated with or without lignosulfonate and containing ground sunflower seeds  

Microsoft Academic Search

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



Application of hand-held and portable infrared spectrometers in bovine milk analysis.  


A simple and fast method for the detection and quantification of milk adulteration was developed using portable and hand-held infrared (IR) spectrometers. Milk samples were purchased from local supermarkets (Columbus, OH, USA) and spiked with tap water, whey, hydrogen peroxide, synthetic urine, urea, and synthetic milk in different concentrations. Spectral data were collected using mid-infrared (MIR) and near-infrared (NIR) spectrometers. Soft independent modeling of class analogy (SIMCA) classification models exhibited tight and well-separated clusters allowing the discrimination of control from adulterated milk samples. Partial least-squares regression (PLSR) was used to estimate adulteration levels, and results showed high coefficients of determination (R(2)) and low standard errors of prediction (SEP). Classification and quantification models indicated that the tested MIR systems were superior to NIR systems in monitoring milk adulteration. This method can be potentially used as an alternative to traditional methods due to their simplicity, sensitivity, low energy cost, and portability. PMID:23339381

Santos, Poliana M; Pereira-Filho, Edenir R; Rodriguez-Saona, Luis E



Potassium in milk and milk products.  

National Technical Information Service (NTIS)

The amount of potassium in imported processed milk was determined by gamma spectral analysis. The results show that the potassium content of diluted infant formula milk is closest to the reported mean concentration of potassium in human milk while other m...

E. Z. Sombrito Z. F. S. Nuguid M. C. Tangonan



The human milk metabolome reveals diverse oligosaccharide profiles.  


Breast milk delivers nutrition and protection to the developing infant. There has been considerable research on the high-molecular-weight milk components; however, low-molecular-weight metabolites have received less attention. To determine the effect of maternal phenotype and diet on the human milk metabolome, milk collected at day 90 postpartum from 52 healthy women was analyzed by using proton nuclear magnetic resonance spectroscopy. Sixty-five milk metabolites were quantified (mono-, di-, and oligosaccharides; amino acids and derivatives; energy metabolites; fatty acids and associated metabolites; vitamins, nucleotides, and derivatives; and others). The biological variation, represented as the percentage CV of each metabolite, varied widely (4-120%), with several metabolites having low variation (<20%), including lactose, urea, glutamate, myo-inositol, and creatinine. Principal components analysis identified 2 clear groups of participants who were differentiable on the basis of milk oligosaccharide concentration and who were classified as secretors or nonsecretors of fucosyltransferase 2 (FUT2) gene products according to the concentration of 2'-fucosyllactose, lactodifucotetraose, and lacto-N-fucopentaose I. Exploration of the interrelations between the milk sugars by using Spearman rank correlations revealed significant positive and negative associations, including positive correlations between fucose and products of the FUT2 gene and negative correlations between fucose and products of the fucosyltransferase 3 (FUT3) gene. The total concentration of milk oligosaccharides was conserved among participants (%CV = 18%), suggesting tight regulation of total oligosaccharide production; however, concentrations of specific oligosaccharides varied widely between participants (%CV = 30.4-84.3%). The variability in certain milk metabolites suggests possible roles in infant or infant gut microbial development. This trial was registered at as NCT01817127. PMID:24027187

Smilowitz, Jennifer T; O'Sullivan, Aifric; Barile, Daniela; German, J Bruce; Lönnerdal, Bo; Slupsky, Carolyn M



Hormone concentrations, mammary development and milk yield in goats given long-term bromocriptine treatment in pregnancy.  


Ten British Saanen goats were treated daily with 5 mg bromocriptine intramuscularly from week 8 of pregnancy until week 20 (day 140). By comparison with untreated control goats (n = 8), concentrations of prolactin in plasma were suppressed throughout the treatment period and remained significantly lower until 3 days prepartum, parturition occurring on day 153 +/- 0.7 (mean +/- S.E.M., n = 10). Growth hormone concentrations were low, but the incidence of levels exceeding 1 microgram/l was increased in bromocriptine-treated goats. Plasma concentrations of placental lactogen, progesterone and oestrone sulphate were unaffected. The accumulation of pre-colostrum in the udder (lactogenesis stage I) was not affected by bromocriptine treatment in goats carrying twin fetuses, but in goats with single kids it was delayed by about 4-6 weeks to week 17 of pregnancy. Secretion could not be expressed from the udder and the concentration of alpha-lactalbumin in plasma remained low. Udder volume was significantly reduced in week 15-16 but not week 20-21 of pregnancy by bromocriptine treatment. Milk yields after 50 or 203 days of lactation were not significantly different from those in control goats. Placental lactogen concentrations in late pregnancy and udder volume in week 20-21 were the only variables measured which correlated with milk yield post partum. It is concluded that in vivo placental lactogen is an effective mammotrophic hormone, although less potent than prolactin as evidenced by the delay in lactogenesis stage I in bromocriptine-treated goats bearing single kids. PMID:3968507

Forsyth, I A; Byatt, J C; Iley, S



Calcium Secretion into Milk  

Microsoft Academic Search

Ionized calcium ([Ca2+]) is present in milk at concentrations around 3 mM, a concentration that drives the formation of complexes with citrate, phosphate, and casein, thereby generating compounds that carry the major portion of calcium in milk. In humans and cows, where it has been studied, changes in milk calcium appear to be regulated by the amount of citrate and

Margaret C. Neville



Dietary vitamin A modulates the concentrations of RRR-alpha-tocopherol in plasma lipoproteins from calves fed milk replacer.  


The practice of supplementing milk replacers fed to neonatal calves with high concentrations of vitamin A has raised concerns regarding the effect of excess vitamin A on the bioavailability of vitamin E. A 4 x 2 factorial experiment evaluated the effects of four dietary amounts of vitamin A [0, 1.78 [National Research Council (NRC)(6) requirement, control], 35.6 and 71.2 micromol daily as retinyl acetate] and two forms of vitamin E (RRR-alpha-tocopherol and RRR-alpha-tocopheryl acetate, 155 micromol daily) on plasma RRR-alpha-tocopherol and RRR-gamma-tocopherol and RRR-alpha-tocopherol associated with plasma lipoproteins (Lp) from milk replacer-fed Holstein calves from birth to 28 d of age. The VLDL, LDL, HDL and very high-density lipoprotein (VHDL) fractions were separated by ultracentrifugal flotation, and the amount of vitamin E associated with each fraction was determined by normal-phase HPLC. The amount and distribution of RRR-alpha-tocopherol in Lp fractions were unaffected by the form of dietary vitamin E. Plasma and Lp RRR-alpha-tocopherol concentrations increased with age (P < 0.0001) and were maximal at 28 d of age. Concentrations of RRR-alpha-tocopherol associated with Lp were 25% (P < 0.01) to 39% (P < 0.0001) lower in calves fed 35.6 and 71.2 micromol of vitamin A daily than in control calves at 28 d of age. The RRR-gamma-tocopherol concentrations were unaffected by dietary vitamin A (P >/= 0.05). In conclusion, dietary vitamin A modulated the amount and distribution of RRR-alpha-tocopherol in the circulation of milk replacer-fed neonatal calves. Because of the essential antioxidant role of vitamin E, the health-related consequences associated with the depression of the LP RRR-alpha-tocopherol concentrations in calves fed vitamin A at 35.6 and 71.2 micromol need to be investigated. PMID:10702596

Ametaj, B N; Nonnecke, B J; Franklin, S T; Horst, R L; Bidlack, W R; Stuart, R L; Beitz, D C



Influence of percentage of concentrate in combination with rolled canola seeds on performance, rumen fermentation and milk fatty acid composition in dairy goats  

Microsoft Academic Search

The effect of rolled canola seeds (RCS, 0% or 20% of the dry matter (DM) of the concentrate) combined with percentage of concentrate (45% (L) vs. 65% (H) of the diet DM) on rumen fermentation characteristics, production parameters and fatty acid (FA) profile of milk fat was studied in 20 entire goats and 12 goats fitted with ruminal and duodenal

P. V. D. Andrade; Ph. Schmidely




Microsoft Academic Search

T HE effect of ration on the synthesis of B-complex vitamins in the rumen has been studied quite extensively and reports may be found in the literature regarding their concentration in the rumen of both cattle and sheep. The concentration of these vitamins in the blood and milk of sheep is reported by Ray et al. (1947) and Pearson and



Docosahexaenoic acid supplementation from mid-pregnancy to parturition influenced breast milk fatty acid concentrations at 1 month postpartum in Mexican women.  


(n-3) PUFA, including DHA, are essential for neural development and accumulate extensively in the fetal and infant brain. (n-3) PUFA concentrations in breast milk, which are largely dependent on maternal diet and tissue stores, are correlated with infant PUFA status. We investigated the effect of prenatal DHA supplementation on PUFA concentrations in breast milk at 1 mo postpartum. In a double-blind, randomized, controlled trial conducted in Mexico, pregnant women were supplemented daily with 400 mg DHA or placebo from 18-22 wk gestation to parturition. Fatty acid concentrations in breast milk obtained from 174 women at 1 mo postpartum were determined using GLC and were expressed as % by weight of total detected fatty acids. Breast milk DHA concentrations in the DHA and placebo groups were (mean ± SD) 0.20 ± 0.06 and 0.17 ± 0.07 (P < 0.01), respectively, and those of ?-linolenic acid (ALA) were 1.38 ± 0.47 and 1.24 ± 0.46 (P = 0.01), respectively. Concentrations of EPA and arachidonic acid did not differ between groups (P > 0.05). Maternal plasma DHA concentrations at 1 mo postpartum correlated positively with breast milk DHA at 1 mo postpartum in both the placebo and DHA groups (r = 0.4; P < 0.01 for both treatment groups). Prenatal DHA supplementation from 18-22 wk gestation to parturition increased concentrations of DHA and ALA in breast milk at 1 mo postpartum, providing a mechanism through which breast-fed infants could benefit. PMID:21178076

Imhoff-Kunsch, Beth; Stein, Aryeh D; Villalpando, Salvador; Martorell, Reynaldo; Ramakrishnan, Usha



Docosahexaenoic Acid Supplementation from Mid-Pregnancy to Parturition Influenced Breast Milk Fatty Acid Concentrations at 1 Month Postpartum in Mexican Women1234  

PubMed Central

(n-3) PUFA, including DHA, are essential for neural development and accumulate extensively in the fetal and infant brain. (n-3) PUFA concentrations in breast milk, which are largely dependent on maternal diet and tissue stores, are correlated with infant PUFA status. We investigated the effect of prenatal DHA supplementation on PUFA concentrations in breast milk at 1 mo postpartum. In a double-blind, randomized, controlled trial conducted in Mexico, pregnant women were supplemented daily with 400 mg DHA or placebo from 18–22 wk gestation to parturition. Fatty acid concentrations in breast milk obtained from 174 women at 1 mo postpartum were determined using GLC and were expressed as % by weight of total detected fatty acids. Breast milk DHA concentrations in the DHA and placebo groups were (mean ± SD) 0.20 ± 0.06 and 0.17 ± 0.07 (P < 0.01), respectively, and those of ?-linolenic acid (ALA) were 1.38 ± 0.47 and 1.24 ± 0.46 (P = 0.01), respectively. Concentrations of EPA and arachidonic acid did not differ between groups (P > 0.05). Maternal plasma DHA concentrations at 1 mo postpartum correlated positively with breast milk DHA at 1 mo postpartum in both the placebo and DHA groups (r = 0.4; P < 0.01 for both treatment groups). Prenatal DHA supplementation from 18–22 wk gestation to parturition increased concentrations of DHA and ALA in breast milk at 1 mo postpartum, providing a mechanism through which breast-fed infants could benefit.

Imhoff-Kunsch, Beth; Stein, Aryeh D.; Villalpando, Salvador; Martorell, Reynaldo; Ramakrishnan, Usha



Vatless manufacturing of low-moisture part-skim mozzarella cheese from highly concentrated skim milk microfiltration retentates.  


Low-moisture, part-skim (LMPS) Mozzarella cheeses were made from concentration factor (CF) 6, 7, 8, and 9, pH 6.0 skim milk microfiltration (MF) retentates using a vatless cheese-making process. The compositional and proteolytic effects of cheese made from 4 CF retentates were evaluated as well as their functional properties (meltability and stretchability). Pasteurized skim milk was microfiltered using a 0.1-microm ceramic membrane at 50 degrees C to a retentate CF of 6, 7, 8, and 9. An appropriate amount of cream was added to achieve a constant casein:fat ratio in the 4 cheesemilks. The ratio of rennet to casein was also kept constant in the 4 cheesemilks. The compositional characteristics of the cheeses made from MF retentates did not vary with retentate CF and were within the legal range for LMPS Mozzarella cheese. The observed reduction in whey drained was greater than 90% in the cheese making from the 4 CF retentates studied. The development of proteolytic and functional characteristics was slower in the MF cheeses than in the commercial samples that were used for comparison due to the absence of starter culture, the lower level of rennet used, and the inhibition of cheese proteolysis due to the inhibitory effect of residual whey proteins retained in the MF retentates, particularly high molecular weight fractions. PMID:15483143

Ardisson-Korat, A V; Rizvi, S S H



Longitudinal increases in PCDD/F and dl-PCB concentrations in human milk in northern China.  


There is a dearth of information on the temporal changes in polychlorinated dibenzodioxin/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) contamination, in both environmental and biological specimens, in China. We compared the concentrations of PCDD/Fs and dl-PCBs in human milk collected in Shijiazhuang, Hebei Province, in northern China in 2002 (n=30) and 2007 (n=20). The level of PCDD/Fs and dl-PCBs showed an increasing trend. The mean concentrations of PCDD/Fs plus dl-PCBs were 4.47 TEQ pg g(-1) fat and 6.24 TEQ pg g(-1) fat in human milk from Shijiazhuang in 2002 and in 2007, respectively. Based on statistical analysis of questionnaire data collected by in-person interviews with mothers, we found positive correlations between consumption of sea fish and PCDFs. The PCDDs, PCDFs, PCDD/Fs, and PCDD/Fs plus dl-PCBs levels in individuals consuming greater amounts of sea fish were higher than those consuming less sea fish, both with and without adjustments for potential confounding factors. Among 17 congeners of PCDD/Fs, the 2,3,7,8-TCDF, 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, and 2,3,4,6,7,8-HxCDF congener concentrations in 2007 increased 134%, 55%, 53%, 57%, 65% and 130% when compared to 2002 levels, respectively. The 2007 dl-PCB congener levels were greater than those of the 2002 samples, with the exception of PCB81 and PCB77. Specifically, PCB105, PCB114, PCB118, PCB123 and PCB156 had increased greater than twofold from 2002 to 2007. Continuous surveillance of PCDD/F and dl-PCB levels in human milk is needed to accurately evaluate both environmental contamination and the human health risk to neonates in China. PMID:21890171

Sun, Su-Ju; Kayama, Fujio; Zhao, Jian-Hong; Ge, Jun; Yang, Yu-Xiu; Fukatsu, Hideo; Iida, Takao; Terada, Mina; Liu, Dian-Wu



Impact of urea on detergent micelle properties.  


Co-solvents, such as urea, can entail drastic changes in the micellization behavior of detergents. We present a systematic quantification of the impact of urea on the critical micellar concentration, the micellization thermodynamics, and the micelle size in three homologous series of commonly used non-ionic alkyl detergents. To this end, we performed demicellization experiments by isothermal titration calorimetry and hydrodynamic size measurements by dynamic light scattering on alkyl maltopyranosides, cyclohexyl alkyl maltopyranosides, and alkyl glucopyranosides at urea concentrations of 0-8 M. For all detergents studied, we found that the critical micellar concentration increases exponentially because the absolute Gibbs free energy of micellization decreases linearly over the entire urea concentration range, as does the micelle size. In contrast, the enthalpic and entropic contributions to micellization reveal more complex, nonlinear dependences on urea concentration. Both free energy and size changes are more pronounced for long-chain detergents, which bury more apolar surface area upon micelle formation. The Gibbs free energy increments per methylene group within each detergent series depend on urea concentration in a linear fashion, although they result from the entropic term for alkyl maltosides but are of enthalpic origin for cyclohexyl alkyl maltosides. We compare our results to transfer free energies of amino acid side chains, relate them to protein-folding data, and discuss how urea-induced changes in detergent micelle properties affect in vitro investigations on membrane proteins. PMID:23745835

Broecker, Jana; Keller, Sandro



Urea Transporter Physiology Studied in Knockout Mice  

PubMed Central

In mammals, there are two types of urea transporters; urea transporter (UT)-A and UT-B. The UT-A transporters are mainly expressed in kidney epithelial cells while UT-B demonstrates a broader distribution in kidney, heart, brain, testis, urinary tract, and other tissues. Over the past few years, multiple urea transporter knockout mouse models have been generated enabling us to explore the physiological roles of the different urea transporters. In the kidney, deletion of UT-A1/UT-A3 results in polyuria and a severe urine concentrating defect, indicating that intrarenal recycling of urea plays a crucial role in the overall capacity to concentrate urine. Since UT-B has a wide tissue distribution, multiple phenotypic abnormalities have been found in UT-B null mice, such as defective urine concentration, exacerbated heart blockage with aging, depression-like behavior, and earlier male sexual maturation. This review summarizes the new insights of urea transporter functions in different organs, gleaned from studies of urea transporter knockout mice, and explores some of the potential pharmacological prospects of urea transporters.

Li, Xuechen; Chen, Guangping; Yang, Baoxue



Plasma Concentration of Urea, Ammonia, Glutamine Around Calving, and the Relation of Hepatic Triglyceride, to Plasma Ammonia Removal and Blood AcidBase Balance  

Microsoft Academic Search

Two experiments were conducted to test the following two hypotheses: 1) fatty liver could hamper hepatic conversion of ammonia to urea and increase circulating ammonia or Gln% (Gln% = Gln * 100\\/(Gln + Glu)) in cows around parturition; 2) decreased ureagenesis might cause alkalosis and in turn reduce blood Ca. In the first experiment, 14 Holstein cows were moni- tored

L. H. Zhu; L. E. Armentano; D. R. Bremmer; R. R. Grummer; S. J. Bertics



Adulteration detection in milk using infrared spectroscopy combined with two-dimensional correlation analysis  

NASA Astrophysics Data System (ADS)

Adulteration of milk and dairy products has brought serious threats to human health as well as enormous economic losses to the food industry. Considering the diversity of adulterants possibly mixed in milk, such as melamine, urea, tetracycline, sugar/salt and so forth, a rapid, widely available, high-throughput, cost-effective method is needed for detecting each of the components in milk at once. In this paper, a method using Fourier Transform Infrared spectroscopy (FTIR) combined with two-dimensional (2D) correlation spectroscopy is established for the discriminative analysis of adulteration in milk. Firstly, the characteristic peaks of the raw milk are found in the 4000-400 cm-1 region by its original spectra. Secondly, the adulterant samples are respectively detected with the same method to establish a spectral database for subsequent comparison. Then, 2D correlation spectra of the samples are obtained which have high time resolution and can provide information about concentration-dependent intensity changes not readily accessible from one-dimensional spectra. And the characteristic peaks in the synchronous 2D correlation spectra of the suspected samples are compared with those of raw milk. The differences among their synchronous spectra imply that the suspected milk sample must contain some kinds of adulterants. Melamine, urea, tetracycline and glucose adulterants in milk are identified respectively. This nondestructive method can be used for a correct discrimination on whether the milk and dairy products are adulterated with deleterious substances and it provides a new simple and cost-effective alternative to test the components of milk.

He, Bin; Liu, Rong; Yang, Renjie; Xu, Kexin



Monitoring of PBDEs concentration in umbilical cord blood and breast milk from Korean population and estimating the effects of various parameters on accumulation in humans.  


In this study, we investigated concentration, congener distribution pattern, and effects of potential environmental factors that affect PBDE accumulation. We also estimated correlation between PBDE concentration and health status or thyroid function by analyzing 90 cord blood and 21 breast milk samples obtained from Korean population. Seven from tri- to hepta-BDEs were analyzed by solid phase extraction-high-resolution gas chromatography/high-resolution mass spectrometry (SPE-HRGC/HRMS). The total concentration of 7 PBDEs in cord blood was 2.786-94.64 ng g(-1) lipid and that in breast milk was 1.076-8.664 ng g(-1) lipid. Tetra-BDE (#47) was the predominant type of PBDE and was present at concentrations of over 40% in both sample types. A weak correlation was observed between the concentration of BDE28 and 153 and thyroid hormone concentration only in the breast milk samples. In children, a weak negative correlation was observed between free thyroxine (FT4) concentration and BDE28 concentration (0.302, p<0.05), while in mothers, a weak positive correlation was observed between thyroid hormone concentration and BDE153 concentration (0.403, p<0.05). No significant correlations between PBDE concentration and work and residential environments were found in this study, but a weak correlation between BDE concentration in cord blood and potential PBDE sources was confirmed by investigating the frequency of oil paint usage (0.510, p<0.001). A weak correlation was also found between PBDE concentration in breast milk during pregnancy and dietary habits such as green tea drinking (0.541, p=0.025) and Trichiuridae intake (0.565, p=0.015). PMID:21890170

Kim, Un-Jung; Lee, In-Seok; Kim, Hyung Sik; Oh, Jeong-Eun



Two flavonolignans from milk thistle (Silybum marianum) inhibit CYP2C9-mediated warfarin metabolism at clinically achievable concentrations.  


Milk thistle (Silybum marianum) is a popular herbal product used for hepatoprotection and chemoprevention. Two commercially available formulations are the crude extract, silymarin, and the semipurified product, silibinin. Silymarin consists of at least seven flavonolignans, of which the most prevalent are the diastereoisomers silybin A and silybin B; silibinin consists only of silybin A and silybin B. Based on a recent clinical study showing an interaction between a silymarin product and the CYP2C9 substrate losartan, the CYP2C9 inhibition properties of silybin A and silybin B and corresponding regioisomers, isosilybin A and isosilybin B, were evaluated using human liver microsomes (HLMs), recombinant CYP2C9 (rCYP2C9) enzymes, and the clinically relevant probe, (S)-warfarin. Silybin B was the most potent inhibitor in HLMs, followed by silybin A, isosilybin B, and isosilybin A (IC(50) of 8.2, 18, 74, and >100 microM, respectively). Next, silybin A and silybin B were selected for further characterization. As with HLMs, silybin B was more potent than silybin A toward rCYP2C9 1 (6.7 versus 12 microM), rCYP2C9 2 (9.3 versus 19 microM), and rCYP2C9 3 (2.4 versus 9.3 microM). Using a matrix of five substrate (1-15 microM) and six inhibitor (1-80 microM) concentrations and HLMs, both diastereoisomers inhibited (S)-warfarin 7-hydroxylation in a manner described best by a mixed-type inhibition model (K(i) values of 4.8 and 10 microM for silybin B and silybin A, respectively). These observations, combined with the high systemic silibinin concentrations (>5-75 microM) achieved in a phase I study involving prostate cancer patients, prompt clinical evaluation of a potential warfarin-milk thistle interaction. PMID:19934397

Brantley, Scott J; Oberlies, Nicholas H; Kroll, David J; Paine, Mary F



Two Flavonolignans from Milk Thistle (Silybum marianum) Inhibit CYP2C9-Mediated Warfarin Metabolism at Clinically Achievable Concentrations  

PubMed Central

Milk thistle (Silybum marianum) is a popular herbal product used for hepatoprotection and chemoprevention. Two commercially available formulations are the crude extract, silymarin, and the semipurified product, silibinin. Silymarin consists of at least seven flavonolignans, of which the most prevalent are the diastereoisomers silybin A and silybin B; silibinin consists only of silybin A and silybin B. Based on a recent clinical study showing an interaction between a silymarin product and the CYP2C9 substrate losartan, the CYP2C9 inhibition properties of silybin A and silybin B and corresponding regioisomers, isosilybin A and isosilybin B, were evaluated using human liver microsomes (HLMs), recombinant CYP2C9 (rCYP2C9) enzymes, and the clinically relevant probe, (S)-warfarin. Silybin B was the most potent inhibitor in HLMs, followed by silybin A, isosilybin B, and isosilybin A (IC50 of 8.2, 18, 74, and >100 ?M, respectively). Next, silybin A and silybin B were selected for further characterization. As with HLMs, silybin B was more potent than silybin A toward rCYP2C9*1 (6.7 versus 12 ?M), rCYP2C9*2 (9.3 versus 19 ?M), and rCYP2C9*3 (2.4 versus 9.3 ?M). Using a matrix of five substrate (1–15 ?M) and six inhibitor (1–80 ?M) concentrations and HLMs, both diastereoisomers inhibited (S)-warfarin 7-hydroxylation in a manner described best by a mixed-type inhibition model (Ki values of 4.8 and 10 ?M for silybin B and silybin A, respectively). These observations, combined with the high systemic silibinin concentrations (>5–75 ?M) achieved in a phase I study involving prostate cancer patients, prompt clinical evaluation of a potential warfarin-milk thistle interaction.

Brantley, Scott J.; Oberlies, Nicholas H.; Kroll, David J.



Urea in rainwater and atmospheric aerosol  

NASA Astrophysics Data System (ADS)

The measurement of urea (CO(NH 2) 2) in rainwater samples from predominantly marine-influenced locations in Bermuda, and Ireland, and in rains and aqueous aerosol extracts from a rural site at UEA, Norwich indicates that urea is not generally a major contributor to atmospheric water-soluble organic nitrogen. At UEA, where anthropogenic and natural sources of urea are expected to be most intense, urea accounts for <10% of rainwater dissolved organic nitrogen (DON), and <1% of the water-soluble fraction of aerosol organic nitrogen. The analysis of size-segregated aerosol samples indicates that the size distribution of urea is quite different from those of ammonium and nitrate. In the less anthropogenically impacted Atlantic sites, rainwater urea was below the detection limits of the colorimetric method used in this study, consistent with expected dilution processes or reaction of urea during transport. However, in a small set of rain samples collected in Tahiti, urea concentrations ranged from 1 to 8 ?mol l -1, accounting for >40% of the DON measured in those samples. This may be a consequence of strong local sources, or it could possibly result from the partial breakdown of other DON compounds to urea during sample transport and storage. However, the similarity in urea concentrations observed in Pacific samples in this present study and in a previous one ( Timperley et al., 1985, Canadian Journal of Fisheries and Aquatic Science42, 1171-1177) suggests that this may reflect a difference in rain chemistry between Atlantic and Pacific rains, perhaps resulting from differences in levels of agricultural urea usage between Asia and the rest of the world.

Cornell, S. E.; Jickells, T. D.; Thornton, C. A.


Synergetic Effects of Nanoporous Support and Urea on Enzyme Activity  

SciTech Connect

Here we report that synergetic effects of functionalized nanoporous support and urea on enzyme activity enhancement. Even in 8.0 M urea, the specific activity of GI entrapped in FMS was still higher than the highest specific activity of GI free in solution, indicating the strong tolerance of GI in FMS to the high concentration of urea.

Lei, Chenghong; Shin, Yongsoon; Liu, Jun; Ackerman, Eric J.



Boron concentrations in milk from mothers of exclusively breast-fed healthy full-term infants are stable during the first four months of lactation.  


Because boron is a bioactive element that satisfies several of the criteria for essentiality in humans, the aim of the present work was to determine the profile of boron metabolism in human milk during the first 4 mo of lactation. The concentration of boron and other minerals was determined in archived milk collected (1980-84) 1 time/mo for 4 mo from lactating mothers of full-term, exclusively breast-fed infants living in Houston, TX. A linear model (treating month as a continuous variable) indicated that B concentrations were stable (P = 0.14) between mo 1 [3.88 +/- 0.6 mumol (42 +/- 6.5 microg)/L milk] and 4 [3.24 +/- 0.6 micromol (35 +/- 6.5 microg)/L milk, mean +/- SEM]. Mg concentrations increased slightly over time (1.18 +/- 0.09 to 1.36 +/- 0.09 mmol/L, P < 0.0001), whereas Ca concentrations decreased slightly (7.01 +/- 0.29 to 6.68 +/- 0.29 mmol/L milk, P < 0.02) and Zn decreased substantially (0.04 +/- 0.004 to 0.02 +/- 0.004 mmol/L milk, P < 0.0001). Similarities in findings reported here and earlier (from samples collected in St. John's, Newfoundland) provide further evidence that boron may be metabolically regulated. Future investigations of boron regulatory mechanisms should focus on metabolism of bone as the major storage site of B and kidney excretion, the major excretory route for B. PMID:16177200

Hunt, Curtiss D; Butte, Nancy F; Johnson, LuAnn K



Changes in concentrations of perfluorinated compounds, polybrominated diphenyl ethers, and polychlorinated biphenyls in Norwegian breast-milk during twelve months of lactation.  


At present, scientific knowledge on depuration rates of persistent organic pollutants (POPs) is limited and the previous assumptions of considerable reduction of body burdens through breast-feeding have recently been challenged. We therefore studied elimination rates of important POPs in nine Norwegian primiparous mothers and one mother breast-feeding her second child by collecting breast-milk samples (n = 70) monthly from about two weeks to up to twelve months after birth. Perfluorinated compounds (PFCs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and polychlorinated biphenyls (PCBs) were determined in the breast-milk samples. Linear mixed effect models were established for selected compounds, and significant decreases in the range of 1.2-4.7% in breast-milk concentrations per month were observed for a wide range of PCBs and PBDEs. For the first time, depuration rates for perfluorooctylsulfonate (PFOS) and perfluorooctanoic acid (PFOA) are presented, being 3.8 and 7.8% per month, respectively (p < 0.05). The relative amount of the branched PFOS isomers in the breast-milk samples was 18% on average (range 6-36%, RSD 30%). There were no significant differences in isomer pattern between the mothers, or changes during the lactation period. After a year of nursing the breast-milk concentrations of PFCs, PBDEs, and PCBs were reduced by 15-94%. PMID:21090747

Thomsen, Cathrine; Haug, Line S; Stigum, Hein; Frřshaug, May; Broadwell, Sharon L; Becher, Georg



Concentrations of DDT, PVBs, HCB, and HCH isomers in the liver and adipose tissue of newborn mice receiving an extract of human milk  

SciTech Connect

Persistent organic chlorine compounds, such as DDT and its metabolites, hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) circulate in the food chain of the ecosystem. Most data on the toxicity and accumulation of organic chlorine compounds have been obtained from animal experiments after chronic or acute poisoning with marketed preparations or standards of the used components of these preparations. In food products of animal origin and in human milk these compounds and their metabolites are present after multiple metabolic steps in varying proportions and concentrations. Their variable amounts are passed to newborns with mother's milk. The purpose of the present study was to investigate in an experimental model of newborn mice the degree of accumulation of these compounds in the liver and adipose tissue after long-standing feeding them with an extract of human milk with added organic chlorine compounds in doses received by human newborns with milk. In the assessment of the relationship between the degree of accumulation of various compounds in the tissues of newborn mice and the daily dose concentrations were used similar to those found in human milk.

Sitarska, E.; Gorski, T.; Ludwick, J.K.



Rapid detection and quantification of milk adulteration using infrared microspectroscopy and chemometrics analysis.  


The application of attenuated total reflectance mid-infrared microspectroscopy (MIR-microspectroscopy) was evaluated as a rapid method for detection and quantification of milk adulteration. Milk samples were purchased from local grocery stores (Columbus, OH, USA) and spiked at different concentrations of whey, hydrogen peroxide, synthetic urine, urea and synthetic milk. Samples were place on a 192-well microarray slide, air-dried and spectra were collected by using MIR-microspectroscopy. Pattern recognition analysis by Soft Independent Modeling of Class Analogy (SIMCA) showed tight and well-separated clusters allowing discrimination of control samples from adulterated milk. Partial Least Squares Regression (PLSR) showed standard error of prediction (SEP) ~2.33, 0.06, 0.41, 0.30 and 0.014 g/L for estimation of levels of adulteration with whey, synthetic milk, synthetic urine, urea and hydrogen peroxide, respectively. Results showed that MIR-microspectroscopy can provide an alternative methodology to the dairy industry for screening potential fraudulent practice for economic adulteration of cow's milk. PMID:23265450

Santos, P M; Pereira-Filho, E R; Rodriguez-Saona, L E



Effect of hydrogen ion concentration and buffer composition on ligand binding characteristics and polymerization of cow's milk folate binding protein.  


The ligand binding and aggregation behavior of cow's milk folate binding protein depends on hydrogen ion concentration and buffer composition. At pH 5.0, the protein polymerizes in Tris-HCl subsequent to ligand binding. No polymerization occurs in acetate, and binding is markedly weaker in acetate or citrate buffers as compared to Tris-HCl. Polymerization of ligand-bound protein was far more pronounced at pH 7.4 as compared to pH 5.0 regardless of buffer composition. Binding affinity increased with decreasing concentration of protein both at pH 7.4 and 5.0. At pH 5.0 this effect seemed to level off at a protein concentration of 10(-6) M which is 100-1000 fold higher than at pH 7.4. The data can be interpreted in terms of complex models for ligand binding systems polymerizing both in the absence or presence of ligand (pH 7.4) as well as only subsequent to ligand binding (pH 5.0). PMID:12166824

Holm, J; Hansen, S I



The relationship between oxidative damage and vitamin E concentration in blood, milk, and liver tissue from vitamin E supplemented and nonsupplemented periparturient heifers  

Microsoft Academic Search

This study investigated the relationship between oxidative damage and the effect of vitamin E supplementation in blood, milk, and liver tissue in 16 periparturient heifers. The question is whether measurements of oxidative and vitamin E status in blood of a periparturient cow are representative of the total body, given that blood concentrations of both vitamin E and oxidative stress products

R. J. Bouwstra; R. M. A. Goselink; P. Dobbelaar; M. Nielen; J. R. Newbold; T. van Werven



Effect of duration and level of supplementation of diets of lactating dairy cows with selenized yeast on selenium concentrations in milk and blood after the withdrawal of supplementation  

Microsoft Academic Search

Cows’ milk containing elevated concentrations of Se provides a rich nutritional source of this essential element for meeting daily nutritional requirements or providing health benefits in humans with low immune function or at risk of cancer. An experiment involving either 2 or 6 wk of dietary supplementation with Se yeast (with the yeast supplying about 30, 40, and 60mg of

C. R. Stockdale; H. S. Gill



Increased concentration of water-soluble carbohydrate in perennial ryegrass (Lolium perenne L.): milk production from late-lactation dairy cows  

Microsoft Academic Search

Eight multiparous Holstein-Friesian dairy cows in late lactation were used to investigate the potential of using perennial ryegrass with a high concentration of water- soluble carbohydrate (WSC) to increase the efficiency of milk production. After a pretreatment period on a common pasture, the cows were each given ad libitum access to one of two varieties of zero-grazed grass continuously for

L. A. Miller; J. M. Moorby; D. R. Davies; M. O. Humphreys; N. D. Scollan; J. C. MacRae; M. K. Theodorou



Stable activity of a deubiquitylating enzyme (Usp2-cc) in the presence of high concentrations of urea and its application to purify aggregation-prone peptides.  


Chemical synthesis of long or aggregation-prone peptide has been problematic. Its biological production has an advantage in that point, but it often forms inclusion body which creates difficulties in recovery of targets. As a deubiquitylating enzyme (Usp2-cc) was shown in this study to maintain its activity even in the presence of up to 4M urea, target peptide was purified by a single step of chromatography after overexpression as inclusion body, solubilization in urea and cleavage by the enzyme from the fusion protein consisting of GroES (used for high expression and easy to handle), ubiquitin (as a cleavage site) and target peptide. This system is a convenient tool for production of peptides that are difficult to be chemically synthesized and biologically purified. PMID:17560941

Shahnawaz, Mohammad; Thapa, Arjun; Park, Il-Seon



Influence of Milk-Clotting Enzyme Concentration on the ?S1Casein Hydrolysis During Soft Cheeses Ripening  

Microsoft Academic Search

We studied the influence of the dose of milk-clotting enzyme on ?s1-CN degradation, soluble nitrogen pro- duction, and sensory profile for an Argentinean soft cheese: Cremoso Argentino. Five different types of cheeses were produced: 1) control cheeses with normal technology, 2) cheeses with inactivated milk-clotting enzyme, 3) cheeses with inactivated milk-clotting en- zyme, without starter (acidified with glucono delta lac-

E. R. Hynes; C. A. Meinardi; N. Sabbag; T. Cattaneo; M. C. Candioti; C. A. Zalazar



Reversible denaturation of cyclosporin synthetase by urea  

Microsoft Academic Search

The reversible denaturation of the multifunctional polypeptide, cyclosporin synthetase, by urea was analyzed. It is possible to discriminate between at least two stages of enzyme denaturation. While at low urea concentration (up to 0.8 M) cyclosporin A formation is inhibited, synthesis of the diketopiperazine cyclo-(d-alanyl-N-methylleucyl), a molecule representing a partial sequence of cyclosporin A is still detectable. At higher concentrations

Joachim Dittmann; François Vaillant; Horst Kleinkauf; Alfons Lawen



Short communication: Annatto in Cheddar cheese-derived whey protein concentrate is primarily associated with milk fat globule membrane.  


The yellow color of Cheddar cheese whey arises from a residual amount of annatto that partitions into the whey during Cheddar cheese manufacture. Bleaching of the color using hydrogen peroxide or benzoyl peroxide is often a prerequisite to produce an acceptable neutral-colored whey protein concentrate and isolate. However, the use of these strong oxidizing agents often generates off-flavors as a result of lipid oxidation and results in loss of nutritive value due to protein oxidation. The objective of this study was to determine the extent of partitioning of annatto between protein, milk fat globule membrane (MFGM), and aqueous (serum) phases of cheese whey so that a simple method can be developed to remove annatto from cheese whey. The MFGM was separated from Cheddar cheese whey using a recently developed novel method. Quantitative analysis of the distribution of annatto in the fat-free whey protein isolate (WPI), the MFGM fractions, and the serum phase revealed that annatto was not bound to the protein fraction but was mostly distributed between the serum phase and the MFGM fraction. The results showed that a colorless WPI or whey protein concentrate could be produced from Cheddar cheese whey by separation of MFGM from the whey, followed by diafiltration. This approach will negate the need for using bleaching agents. PMID:22281326

Zhu, D; Damodaran, S



Effect of dietary concentration of total nonstructural carbohydrate on energy and nitrogen metabolism and milk production of dairy cows.  


Two complete blended diets with a ratio of concentrate: silage dry matter of 60:40 were fed to 12 Holstein cows in the first 12 wk of lactation in an incomplete changeover arrangement of treatments. Diets differed (dry basis) in content of total nonstructural carbohydrate (24.9% versus 32.9%), neutral detergent fiber (37.0% versus 32.1%), and hemicellulose (19.6% versus 15.7%) but were similar in amounts of lignin, crude protein, soluble nitrogen, and acid detergent insoluble nitrogen. The diet with more total nonstructural carbohydrate was associated with greater dry matter intake as a percentage of body weight and greater yields of milk and solids-not-fat. Cellulose digestibility and mean rumen ammonia concentration were lower with this diet. Despite similar protein solubilities, the diet with more total nonstructural carbohydrate contained more rumen degradable nitrogen (80% versus 60%) but similar amounts of rumen degradable dry matter (82% versus 79%). The metabolizable energy of this diet was used more efficiently for the combined functions of maintenance and production, and net energy for lactation was larger (2.2 versus 1.9 Mcal/kg dry matter), as measured calorimetrically. PMID:6833593

MacGregor, C A; Stokes, M R; Hoover, W H; Leonard, H A; Junkins, L L; Sniffen, C J; Mailman, R W



Concentrated bovine milk whey active proteins facilitate osteogenesis through activation of the JNK-ATF4 pathway.  


Concentrated fractions of low molecular weight whey proteins (1-30 kDa), that is concentrated bovine milk whey active proteins (CBP), have been found to enhance bone formation in both in vivo and clinical studies, but the underlying mechanisms are poorly understood. In this study, we found that CBP promoted osteoblastic differentiation in normal human osteoblasts, and determined the involvement of the c-jun NH2-terminal kinase (JNK)-activating transcription factor 4 (ATF4) pathway. We observed that alkaline phosphatase activity and mineralization were significantly induced by CBP treatment. In addition, mRNA expression of ATF4 was intensely elevated in CBP-treated osteoblasts, indicating that the late-phase events of differentiation were promoted. We found that CBP activated the phosphorylation of JNK and extracellular signal-regulated kinase (ERK). Furthermore, pathway analyses using the various signaling pathway-specific inhibitors revealed that JNK activation, but not ERK activation, is essential for CBP-induced mineralization and ATF4 expression. Our results indicate that the JNK-mediated ATF4 pathway is required for CBP-promotive osteogenesis. PMID:22790938

Tsuji-Naito, Kentaro; Jack, Ralph W



Monitoring of PBDEs concentration in umbilical cord blood and breast milk from Korean population and estimating the effects of various parameters on accumulation in humans  

Microsoft Academic Search

In this study, we investigated concentration, congener distribution pattern, and effects of potential environmental factors that affect PBDE accumulation. We also estimated correlation between PBDE concentration and health status or thyroid function by analyzing 90 cord blood and 21 breast milk samples obtained from Korean population. Seven from tri- to hepta-BDEs were analyzed by solid phase extraction-high-resolution gas chromatography\\/high-resolution mass

Un-Jung Kim; In-Seok Lee; Hyung Sik Kim; Jeong-Eun Oh



Milk fatty acid composition of dairy cows grazing at two pasture allowances and supplemented with different levels and sources of concentrate  

Microsoft Academic Search

Milk fatty acid (FA) composition of dairy cows from two grazing studies was examined. In the first study, effects of concentrate supplementation and pasture allowance were evaluated using 20 multiparous Holstein cows in five 4×4 Latin squares. The four treatments resulted from the combination of two pasture allowances (i.e., low, 25 versus high, 40kg dry matter\\/cow\\/day) and two concentrate supplementation

F. Bargo; J. E. Delahoy; G. F. Schroeder; L. D. Muller




PubMed Central

The extent of urea denaturation depends on the concentration of protein and urea and also on the temperature of the solution. Egg albumin solutions (0.9 per cent) are not denatured by 20 per cent urea, denature slowly with 25 per cent urea, and denature rapidly with 35 per cent urea at room temperature. At a higher temperature 30 per cent urea is rapidly effective. Denaturation of the egg albumin molecule by radiation or by heat is accompanied by structural changes as evidenced by optical rotation values, but is not accompanied by association or dissociation of the molecule in the pH range outside the zone in which aggregation follows denaturation. Denaturation of the egg albumin molecule by urea produces no change in optical rotation until the concentration of urea is high enough to dissociate the molecule. In the presence of urea a urea-protein complex is formed in which the protein is denatured but cannot flocculate because of the dispersive action of the urea. This prevents flocculation of proteins exposed to radiation and subsequent heating to 40° C. as the urea-protein complex is not broken down at a temperature of 40° C. The presence of urea therefore prevents the flocculation of proteins denatured by radiation. The urea-protein complex is broken down by heating to 55–58° C. so that the molecules aggregate at a temperature below the temperature of rapid heat denaturation. This appears to be an acceleration of heat denaturation or a lowering of the heat denaturation temperature, but in reality is an effect of heat on the urea-protein complex which frees the urea-denatured protein and permits its aggregation.

Clark, Janet H.



Effect of Dietary Crude Protein Concentration on Milk Production and Nitrogen Utilization in Lactating Dairy Cows1  

Microsoft Academic Search

Forty lactating Holstein cows, including 10 with rumi- nal cannulas, were blocked by days in milk into 8 groups and then randomly assigned to 1 of 8 incomplete 5 × 5 Latin squares to assess the effects of 5 levels of dietary crude protein (CP) on milk production and N use. Diets contained 25% alfalfa silage, 25% corn silage, and

J. J. Olmos Colmenero; G. A. Broderick



The Effect of Feeding Cottonseed Meal as the only Concentrate on Several Properties of Milk. II. Nitrogen Distribution  

Microsoft Academic Search

Investigations (2, 5, 9, 11) have shown that feeding a high level of protein increases the non-protein nitrogen content of the milk. Although this is generally accepted to be the only direct effect of feed on the nitrogen composition of milk, some investigators (3, 10) have observed a slight variation in other nitrogen fractions accompanying changes in the level of

P. G. Miller; G. H. Wise



Inclusion of psyllium in milk replacer for neonatal calves. 2. Effects on volatile fatty acid concentrations, microbial populations, and gastrointestinal tract size.  


Fermentable fibers such as psyllium increase volatile fatty acid (VFA) concentrations in the lower digestive tract and increase the gastrointestinal tract (GIT) mass of many mammals. We reasoned that psyllium inclusion in milk replacer might produce similar effects in neonatal dairy calves, which could lead to improved growth and health. Male Holstein calves were fed a milk replacer (22% crude protein, 20% fat) either without or with psyllium (1.1% of dry matter, DM) from 2 d through 28 d of age. Milk replacer was reconstituted to 12.5% DM and fed at 12% of calf body weight, adjusted weekly. Water was offered ad libitum but no starter was fed. Three calves per treatment were harvested weekly to sample digesta from the reticulo-rumen, abomasum, jejunum, proximal colon, and distal colon, and to determine length and mass of GIT components. Psyllium in milk replacer increased the proportion of butyrate in reticulo-rumen contents from 2.4 to 3.2% of total but did not affect total VFA concentrations. Total VFA concentrations were very low in the jejunum but psyllium tended to increase total VFA, acetate, and valerate concentrations; valerate accounted for 15.9 and 16.7% of total VFA (molar basis) for control and psyllium calves, respectively. Psyllium increased total VFA concentrations in the proximal and distal colon by 104.4 and 45.6%, respectively, but had little effect on the profile of VFA. Psyllium in milk replacer increased populations of bifidobacteria (from 9.7 to 10.3 log(10) cfu/g of DM) and lactobacilli (from 8.2 to 9.4 log(10) cfu/g of DM) in the reticulo-rumen, but did not affect populations in jejunum or colon. Calves fed psyllium had 12.0% greater total GIT mass and 9.4% greater GIT as a percentage of body weight. Psyllium tended to increase mass of the reticulo-rumen and significantly increased mass of duodenum (34.2%), jejunum (14.5%), and colon (14.6%). Density of intestinal tissues from calves fed psyllium-supplemented milk replacer was 25.9% greater in the jejunum and 25.3% greater in the ileum, and tended to be greater in duodenum and colon than tissue from control calves. Supplementation of psyllium to milk replacer increased fermentation in the colon, mass of the total GIT, and populations of bifidobacteria and lactobacilli in the reticulo-rumen. PMID:20855009

Cannon, S J; Fahey, G C; Pope, L L; Bauer, L L; Wallace, R L; Miller, B L; Drackley, J K



Detection of Interstellar Urea  

Microsoft Academic Search

Urea, a molecule discovered in human urine by H. M. Rouelle in 1773, has a significant role in prebiotic chemistry. Previous BIMA observations have suggested that interstellar urea [(NH2)2CO] is a compact hot core molecule such as other large molecules (e.g. methyl formate and acetic acid). We have conducted an extensive search for urea toward the high mass hot molecular

Hsin-Lun Kuo; Anthony J. Remijan; Lewis E. Snyder; Leslie W. Looney; Douglas N. Friedel; Francis J. Lovas; Benjamin J. McCall; Jan M. Hollis



Concentration-time courses of pefloxacin in plasma and milk of lactating she-camels (Camelus dromedarius).  


Using the microbial inhibition test, the single-dose pharmacokinetics of pefloxacin mesylate dehydrate were studied in six clinically normal lactating she-camels (Camelus dromedarius) after intravenous (IV) and intramuscular (IM) administration of 10 mg/kg body weight (bwt). Blood and milk samples were collected intermittently for a 48 h period, and the pharmacokinetic variables were calculated using compartmental and non-compartmental analytical methods.The plasma course of pefloxacin was best resolved to a two-compartment open model after IV administration and a two-compartment open model with first-order absorption after IM administration. Pefloxacin exhibits a long elimination-phase disposition half-life (t1/2beta) of 4.89 +/- 1.12 h after IV injection and 5.73 +/- 1.42 h after IM administration. The mean volume of distribution at steady state (Vdss) and total body clearance (Cl(tot)) values after IV dosing were 1.18 +/- 0.45 I/kg and 0.21 +/- 0.10 I/kg/h, respectively. The observed peak plasma level (Cmax) of 3.6 +/- 0.1 microg/ml was rapidly attained at 0.75 h (the time of maximum concentration Tmax) after IM administration. The areas under the concentration versus time curves (AUCs) were 44.18 +/- 9.68 microg x h/ml and 29.42 +/-6.49 microg x h/ml after IV and IM administration, respectively. The absolute bioavailability (F%) obtained after IM administration was 71.59 +/- 12.45%. Milk was penetrated quickly, with a mean peak level of 3.24 +/- 0.17 microg/ml occurring at 1.0 h. The elimination half-life was significantly shorter after IV versus IM administration (4.21 +/- 0.84 h versus 5.32 +/- 0.67 h, respectively). Ultimately, pefloxacin could be useful for treatment of udder infections in she-camels after specific assessment of susceptible microorganisms. PMID:19086693

Goudah, Ayman; Shah, Syed Sher; Shin, Ho-Chul; Chang, Byung-Joon; Shim, Jae-Han; Abd El-Aty, A M


Milk composition, milk fatty acid profile, digestion, and ruminal fermentation in dairy cows fed whole flaxseed and calcium salts of flaxseed oil.  


Four ruminally lactating Holstein cows averaging 602+/-25 kg of body weight and 64+/-6 d in milk at the beginning of the experiment were randomly assigned to a 4 x 4 Latin square design to determine the effects of feeding whole flaxseed and calcium salts of flaxseed oil on dry matter intake, digestibility, ruminal fermentation, milk production and composition, and milk fatty acid profile. The treatments were a control with no flaxseed products (CON) or a diet (on a dry matter basis) of 4.2% whole flaxseed (FLA), 1.9% calcium salts of flaxseed oil (SAL), or 2.3% whole flaxseed and 0.8% calcium salts of flaxseed oil (MIX). The 4 isonitrogenous and isoenergetic diets were fed for ad libitum intake. Experimental periods consisted of 21 d of diet adaptation and 7 d of data collection and sampling. Dry matter intake, digestibility, milk production, and milk concentrations of protein, lactose, urea N, and total solids did not differ among treatments. Ruminal pH was reduced for cows fed the CON diet compared with those fed the SAL diet. Propionate proportion was higher in ruminal fluid of cows fed CON than in that of those fed SAL, and cows fed the SAL and CON diets had ruminal propionate concentrations similar to those of cows fed the FLA and MIX diets. Butyrate concentration was numerically higher for cows fed the SAL diet compared with those fed the FLA diet. Milk fat concentration was lower for cows fed SAL than for those fed CON, and there was no difference between cows fed CON and those fed FLA and MIX. Milk yields of protein, fat, lactose, and total solids were similar among treatments. Concentrations of cis-9 18:1 and of intermediates of ruminal biohydrogenation of fatty acids such as trans-9 18:1 were higher in milk fat of cows fed SAL and MIX than for those fed the CON diet. Concentration of rumenic acid (cis-9, trans-11 18:2) in milk fat was increased by 63% when feeding SAL compared with FLA. Concentration of alpha-linolenic acid was higher in milk fat of cows fed SAL and MIX than in milk of cows fed CON (75 and 61%, respectively), whereas there was no difference between FLA and CON. Flaxseed products (FLA, SAL, and MIX diets) decreased the n-6 to n-3 fatty acid ratio in milk fat. Results confirm that flax products supplying 0.7 to 1.4% supplemental fat in the diet can slightly improve the nutritive value of milk fat for better human health. PMID:20630232

Côrtes, C; da Silva-Kazama, D C; Kazama, R; Gagnon, N; Benchaar, C; Santos, G T D; Zeoula, L M; Petit, H V



Effects at early stage of life of elevated milk replacer feeding on growth rate, plasma IGF-I concentration and intestinal nutrient transporter expression in Holstein bull calves.  


In order to evaluate the effects of an elevated amount of modified milk replacer on body weight, daily gain, starter intake, plasma endocrine parameters and expression of nutrient transporters in small intestinal epithelia, Holstein bull calves (n=24) were fed for 60days either with the usual amount of 24% crude protein (CP) and 20% fat milk (CF) replacer (C group), or with a double amount of a modified milk replacer of 28% CP and 16% CF (E group). Body weight from D20 to D60 and daily gain before D40 was greater or tended to be greater for the E group than the C group. Plasma concentrations of insulin-like growth factor-1 (IGF-I) and insulin were greater for the E group than the C group on D28 but not on D56, without changing plasma growth hormone levels. Gene expression for sodium-dependent glucose transporter 1 and fatty acid translocase (CD36) was altered in day- and intestine-dependent manners. From these findings, we conclude that an elevated intake of milk replacer given up to 40days old is sufficient to enhance body weight, which may be associated with increased plasma IGF-I concentrations, in Holstein bulls. PMID:22250743

Orihashi, Takenori; Mashiko, Takanori; Sera, Kenji; Roh, Sang-Gun; Katoh, Kazuo; Obara, Yoshiaki



IGF-I gene polymorphism, but not its blood concentration, is associated with milk fat and protein in Holstein dairy cows.  


We estimated the allele and genotype frequencies of IGF-I/SnaBI gene polymorphism and the concentration of this protein in Holstein dairy cows. We also examined the association with milk yield (305-day milk yield) and milk components (fat and protein percentage, and 305-day milk protein and fat yield). Blood IGF-I levels were measured and genotyping was performed on 250 Holstein cows of four different herds. In the association studies, traits of interest were analyzed using the GLM procedure of SAS; means of the IGF-I level among genotypes were compared by the LSMeans test. The AB and AA genotypes were the most (0.583-0.661) and least (0.083-0.192) frequent in the herds, respectively; the frequency of the BB genotype ranged from 0.201 to 0.333. The frequency of the A allele ranged from 0.375 to 0.495, while the frequency of the B allele ranged from 0.504 to 0.625, being the dominant allele. The mean level of IGF-I was 107 +/- 22 ng/mL for all groups, without any significant correlation with the production traits. Association of IGF-I/SnaBI genotypes with percentage of fat and protein in the milk was relatively high (P < 0.1 and P < 0.05, respectively); the AB genotype was superior to AA and BB genotypes. We concluded that this marker should be considered for milk component selection in Holstein dairy cattle. PMID:20812193

Bonakdar, E; Rahmani, H R; Edriss, M A; Sayed Tabatabaei, B E



Milk Allergy  


Milk Allergy Allergy to cow’s milk is the most common food allergy in infants and young children. Symptoms of ... threatening (read more about anaphylaxis ). Differences between Milk Allergy and Lactose Intolerance Milk allergy should not be ...


Urea is a dynamic pool of bioavailable nitrogen in coral reefs  

NASA Astrophysics Data System (ADS)

Urea may be an important source of nitrogen in low nutrient coral reef environments because corals and other organisms can assimilate it easily and it is found throughout ocean waters. We measured the distribution and concentrations of urea in seagrass beds, areas of schooling fish, coral formations and bottom sediments in the Upper Florida Keys Reef Tract. The flux of urea from bottom sediments was also measured. Ambient concentrations of urea in the offshore reefs were similar to the concentrations of nitrate and ammonium. Seagrass beds, areas of schooling fish and coral formations had elevated concentrations of urea that were up to eight times higher than nitrate in the system. Numerous ephemeral hotspots of urea that were 8-20 times the ambient urea concentration existed in seagrass beds, areas of schooling fish, and above sediments. Coastal areas and inland canals had high urea concentrations where urban runoff and septic effluents were prevalent, but there was no anthropogenic influence in the offshore habitats. Urea concentrations above bottom sediments were not different from ambient concentrations and benthic flux chamber incubations showed biological activity in carbonaceous sediments but no net urea production. The decrease in urea concentrations from coasts and inland waterways to a consistent ambient concentration in the offshore reef system and ephemeral hotspots of high urea concentration suggest that urea is a dynamic pool of bioavailable nitrogen in the reefs of the Upper Florida Keys.

Crandall, J. B.; Teece, M. A.



Popular ovine and caprine fermented milks  

Microsoft Academic Search

Ovine and caprine milk are widely produced in semi-arid countries, and mainly utilised for milk consumption and the manufacture of a wide range of cheeses, fermented milk products (e.g. liquid, viscous, concentrated and dried) and to a lesser degree milk powder. The primary aim of this review is to provide a critical analysis of the main components of milk from

A. Y. Tamime; M. Wszolek; R. Božani?; B. Özer


Yield and sensory properties of cheese made with milk from Holstein or Montbeliarde cows milked twice or once daily.  


The aim of this study was to evaluate the milk properties and the yield and sensory properties of Cantal cheese made with milk from Holstein or Montbéliarde cows milked once or twice daily. Sixty-four grazing cows [32 Holstein (H) and 32 Montbéliarde (M) cows] in the declining phase of lactation (157 d in milk) were allocated to 1 of 2 equivalent groups milked once daily (ODM) or twice daily (TDM) for 7 wk. The full-fat raw milk collected during 24 h from the 4 groups of cows (M-TDM, M-ODM, H-TDM, and H-ODM) was pooled and processed into Cantal cheese 4 times during the last 4 wk of the experimental period. In all, 16 cheeses were made (2 milking frequencies x 2 breeds x 4 replicates) and analyzed after a ripening period of 15 and 28 wk. The results showed that for both breeds, the pooled milk content of fat, whey protein, casein, total protein, and phosphorus as well as rennet clotting time and curd firming time were significantly higher with ODM cows, whereas the casein-to-total protein ratio was lower, and lactose, urea, calcium, and free fatty acids contents of milk remained unchanged. The acidification and draining kinetics of the cheese as well as cheese yields and the chemical and rheological properties of the ripened cheese were not significantly modified by milking frequency. For both breeds, the cheeses derived from ODM cows had a slightly yellower coloration but the other sensory attributes, except for pepper odor, were not significantly affected by milking frequency, thereby demonstrating that ODM does not have an adverse effect on the sensory properties of Cantal cheese. Compared with that of Holstein cows, milk from Montbéliarde cows resulted in a higher cheese yield (+1.250 kg/100 kg of milk) and ripened cheeses with lower pH, dry matter, calcium, sodium chloride, and water-soluble nitrogen concentrations. These cheeses had also a less firm and more elastic texture, a more acidic taste, and a yogurt/whey aroma. PMID:19762788

Martin, B; Pomičs, D; Pradel, P; Verdier-Metz, I; Rémond, B



Effects of Dry Matter Intake, Addition of Buffer, and Source of Fat on Duodenal Flow and Concentration of Conjugated Linoleic Acid and Trans11C18:1 in Milk  

Microsoft Academic Search

The primary objective of the study was to investigate the effects of DM intake, addition of buffer, and fish vs. soybean oil on duodenal flows and milk concentrations of conjugated linoleic acid (CLA) and trans-11 C18:1. Four ruminally and duodenally cannulated multipa- rous cows averaging 106 ± 17 d in milk at the start of the trial were used in

X. Qiu; M. L. Eastridge; J. L. Firkins



Effect of supplementing napier grass ( Pennisetum purpureum) with sunflower meal or poultry litter-based concentrates on feed intake, live-weight changes and economics of milk production in Friesian cows  

Microsoft Academic Search

A study was conducted using a randomized complete block design to determine feed intake, live-weight changes, milk yield and cost of milk production in Friesian cows fed napier grass (NG) at 10 weeks (MNG) or 15 weeks (ONG) of maturity. The MNG or ONG was supplemented with equal amounts of sunflower (SFBC) or poultry litter (PLBC) based concentrates in experiment

J. M. K Muia; S Tamminga; P. N Mbugua



Effects of alfalfa hay particle size in high-concentrate diets supplemented with unsaturated fat: Chewing behavior, total-tract digestibility, and milk production of dairy cows.  


This study evaluated the effects of increasing the physically effective neutral detergent fiber (peNDF) intake of lactating dairy cows fed high-concentrate diets supplemented with unsaturated fat on intake, eating behavior, diet sorting, chewing activity, total-tract digestibility, and milk production and composition. Diets contained 24% alfalfa hay (AH), 16% corn silage, 58% concentrate, and 2% yellow grease [dry matter (DM) basis], and dietary peNDF content was increased by varying the particle size (PS) of the AH. Nine multiparous cows averaging 87.8±14.8d in milk and weighing 653±53kg were randomly assigned to a triplicate 3×3 Latin square. During each 21-d period, cows were offered 1 of 3 total mixed rations that varied in PS of AH: fine, medium, and long, with a geometric mean particle length of 3.00, 3.57 and 3.87mm, respectively. Increasing PS quadratically affected DM intake (DMI; 24.7, 25.4, and 23.7kg/d, for fine, medium, and long, respectively), but cumulative DMI at 2, 4, and 6h after feeding was similar across treatments, averaging 23.4, 35.6 and 46.4% of total DMI for the 3 time points, respectively. Increased peNDF intake did not affect feed sorting, but increased daily eating time, and eating and total chewing time per kilogram of DMI. Daily rumination time exhibited a quadratic response, with highest rumination time for the medium diet. Dietary PS had no effects on digestibility in the total tract, but we observed, for fine, medium, and long diets, quadratic responses in milk production (41.5, 43.3, and 40.4kg/d), 4% fat-corrected milk production, and milk protein yield. Milk fat content decreased linearly with increasing PS, but milk fat content and fat:protein ratio were low for all treatments, likely due to adding unsaturated fat to a diet containing a high level of nonfiber carbohydrates (42.2% of DM). The composition, degree of saturation, and total conjugated linoleic acid content of fatty acids in milk fat were not affected by the change in peNDF content of the diet. The study indicates that a moderate increase in the PS of AH in diets containing unsaturated fat elevates peNDF intake and increases chewing activity, DMI, milk yield and milk fat production. However, the effects of dietary PS were quadratic, with maximum DMI and milk production observed with diets supplying 24% dietary peNDF (measured as the proportion of the ration retained on sieves >1.18mm multiplied by dietary neutral detergent fiber content; DM basis). PMID:24054282

Kahyani, A; Ghorbani, G R; Khorvash, M; Nasrollahi, S M; Beauchemin, K A



Effects of induced energy deficiency on lactoferrin concentration in milk and the lactoferrin reaction of primary bovine mammary epithelial cells in vitro.  


A dietary energy restriction to 49% of total energy requirements was conducted with Red Holstein cows for three weeks in mid-lactation. At the last day of the restriction phase, primary bovine mammary epithelial cells (pbMEC) of eight restriction (RF) and seven control-fed (CF) cows were extracted out of one litre of milk and cultured. In their third passage, an immune challenge with the most prevalent, heat-inactivated mastitis pathogens Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was conducted. Lactoferrin (LF) was determined on gene expression and protein level. An enzyme-linked immunosorbent assay (ELISA) was developed to determine LF in milk samples taken twice weekly throughout the animal trial, beginning on day 20 pp (post-partum) until day 150 pp, in cell culture total protein and in cell culture supernatant. Milk LF increased throughout the lactation and decreased significantly during the induced energy deficiency in the RF group. At the beginning of realimentation, LF concentration increased immediately in the RF group and reached higher levels than before the induced deficit following the upward trend seen in the CF group. Cell culture data revealed higher levels (up to sevenfold up-regulation in gene expression) and significant higher LF protein concentration in the RF compared to the CF group cells. A further emphasized effect was found in E. coli compared to S. aureus exposed cells. The general elevated LF levels in the RF pbMEC group and the further increase owing to the immune challenge indicate an unexpected memory ability of milk-extracted mammary cells that were transposed into in vitro conditions and even displayed in the third passage of cultivation. The study confirms the suitability of the non-invasive milk-extracted pbMEC culture model to monitor the influence of feeding experiments on immunological situations in vivo. PMID:22540894

Danowski, K; Gross, J J; Meyer, H H D; Kliem, H



Induction of and recovery from milk fat depression occurs progressively in dairy cows switched between diets that differ in fiber and oil concentration.  


Milk fat depression (MFD) caused by intermediates of ruminal biohydrogenation commonly occurs in dairy cattle. The time course of recovery from MFD is important to mechanistic investigation and management of the condition. Nine cows were used in a repeated design, allowing analysis of recovery from diet-induced MFD. A high-fiber, low-oil diet was fed during the control and recovery periods, and a low-fiber, high-oil (LFHO) diet was fed during the induction period. Milk yield was not affected by treatment. Milk fat percentage and yield decreased progressively during induction and were lower by d 3 and 5, respectively. Milk fat concentration and yield increased progressively when cows were fed the recovery diet and were not different from control on d 19 and 15, respectively. Yield of de novo synthesized fatty acids (FA) decreased progressively during the induction period and was lower than that of controls by d 5. A biphasic response was seen for milk fat trans isomers, where trans-11 C18:1 and cis-9,trans-11 conjugated linoleic acid (CLA) were elevated initially and trans-10 C18:1 and trans-10,cis-12 CLA increased progressively during the induction period. A similar biphasic response was seen during recovery from MFD, with trans-10 C18:1 and trans-10,cis-12 rapidly decreasing initially and trans-11 C18:1 and cis-9,trans-11 CLA increasing slightly above control levels during the second phase. Recovery from diet-induced MFD occurs gradually with a short lag when dietary fiber and oil concentrations are corrected. This time course provides a framework to identify factors causing MFD and set expectations during recovery from MFD. PMID:23958016

Rico, Daniel E; Harvatine, Kevin J



Influence of adsorbed milk protein type and surface concentration on the quiescent and shear stability of butteroil emulsions  

Microsoft Academic Search

Understanding of the relationship between adsorbed milk protein layer characteristics and stability of butteroil emulsions may be applied to create emulsions with specific properties such as ice cream emulsions (quiescently stable, destabilizing under shear) formulated without chemical surfactant. Emulsions created from butteroil (25%) with skim milk powder (SMP) (0.2–0.7%), whey protein hydrolysate (WPH) (1.6–2.1%), whey protein isolate (WPI) (0.2–0.7%) and

K. I. Segall; H. D. Goff



Triiodothyronine administration affects urea synthesis in rats.  


The purpose of the present study was to elucidate the mechanism by which thyroid hormone alters urea synthesis. The relative importance of urea cycle enzyme activities, substrate levels or the levels of urea cycle intermediates on urea production was investigated in a set of four experiments in which rats were fed a diet supplemented with 6-propyl-2-thiouracil (PTU, a thyroid inhibitor) and treated with triiodothyronine (T3). Compared with that of normal or control rats, the plasma level of T3 was significantly lower in rats fed a diet containing PTU only and elevated in rats given PTU + T3. Urinary excretion of urea and the liver content of ornithine in rats given PTU + T3 were significantly lower than in rats given PTU only. The liver level of ornithine was closely correlated to the excretion of urea in the present study. Fractional rates of protein synthesis in liver, kidney and small intestine were lower in the hypothyroid group. However, most free amino acid concentrations, except ornithine in liver and plasma and the activity of hepatic argininosuccinate synthetase (EC of hypothyroid rats, were significantly reduced as compared with those of control or hyperthyroid rats. The results indicate that the increased hepatic ornithine content in the hypothyroid rats may be one of the regulatory factors causing changes in urea synthesis. PMID:2051240

Hayase, K; Yonekawa, G; Yokogoshi, H; Yoshida, A



Simultaneous detection of multiple adulterants in dry milk using macro-scale Raman chemical imaging.  


The potential of Raman chemical imaging for simultaneously detecting multiple adulterants in milk powder was investigated. Potential chemical adulterants, including ammonium sulphate, dicyandiamide, melamine, and urea, were mixed together into skim dry milk in the concentration range of 0.1-5.0% for each adulterant. Using a 785-nm laser, a Raman imaging system acquired hyperspectral images in the wavenumber range of 102-2538 cm(-1) for a 25 × 25 mm(2) area of each mixture sample, with a spatial resolution of 0.25 mm. Self-modelling mixture analysis (SMA) was used to extract pure component spectra, by which the four types of the adulterants were identified at all concentration levels based on their spectral information divergence values to the reference spectra. Raman chemical images were created using the contribution images from SMA, and their use to effectively visualise identification and spatial distribution of the multiple adulterant particles in the dry milk was demonstrated. PMID:23411206

Qin, Jianwei; Chao, Kuanglin; Kim, Moon S



Comparison of Flavor and Physical Properties of Foam Spray-Dried Whole Milks Prepared from Concentrates Foamed with Air and with Nitrogen  

Microsoft Academic Search

Foam spray-dried whole milks pre- pared from concentrates foamed with nitrogen, air from cylinders, and air from a plant-installed compressor were com- pared regarding certain physical proper- ties and flavor, initially and after oxygen- free storage for 3 and 6 months at 4C. No evidence was found for variations in either physical properties or flavor at- tributable to the foaming

A. Tamsma; F. E. Kurtz; M. J. Pallansch



Effects of forage type, forage to concentrate ratio, and crushed linseed supplementation on milk fatty acid profile in lactating dairy cows  

Microsoft Academic Search

The effects of an increasing proportion of crushed linseed (CL) in combination with varying forage type (grass or corn silage) and forage to concentrate ratio (F:C), and their interactions on milk fatty acid (FA) profile of high-producing dairy cows was studied using a 3-factor Box-Behnken design. Sixteen Holstein and 20 Swedish Red cows were blocked according to breed, parity, and

A. R. Sterk; B. E. O. Johansson; H. Z. H. Taweel; M. Murphy; Vuuren van A. M; W. H. Hendriks; J. Dijkstra



Effects of feeding wheat or corn-wheat dried distillers grains with solubles in low- or high-crude protein diets on ruminal function, omasal nutrient flows, urea-N recycling, and performance in cows.  


A study was conducted to determine the effects of including either wheat-based (W-DDGS) or corn-wheat blend (B-DDGS) dried distillers grains with solubles as the major protein source in low- or high-crude protein (CP) diets fed to dairy cows on ruminal function, microbial protein synthesis, omasal nutrient flows, urea-N recycling, and milk production. Eight lactating Holstein cows (768.5±57.7kg of body weight; 109.5±40.0d in milk) were used in a replicated 4×4 Latin square design with 28-d periods (18d of dietary adaptation and 10d of measurements) and a 2×2 factorial arrangement of dietary treatments. Four cows in one Latin square were ruminally cannulated for the measurement of ruminal fermentation characteristics, microbial protein synthesis, urea-N recycling kinetics, and omasal nutrient flow. The treatment factors were type of distillers co-product (W-DDGS vs. B-DDGS) and dietary CP content [15.2 vs. 17.3%; dry matter (DM) basis]. The B-DDGS was produced from a mixture of 15% wheat and 85% corn grain. All diets were formulated to contain 10% W-DDGS or B-DDGS on a DM basis. No diet effect was observed on DM intake. Yields of milk, fat, protein, and lactose, and plasma urea-N and milk urea-N concentrations were lower in cows fed the low-CP compared with those fed the high-CP diet. Although feeding B-DDGS tended to reduce ruminal ammonia-N (NH3-N) concentration compared with feeding W-DDGS (9.3 vs. 10.5mg/dL), no differences were observed in plasma urea-N and milk urea-N concentrations. Additionally, dietary inclusion of B-DDGS compared with W-DDGS did not affect rumen-degradable protein supply, omasal flows of total N, microbial nonammonia N (NAN), rumen-undegradable protein, and total NAN, or urea-N recycling kinetics and milk production. However, cows fed the low-CP diet had lower N intake, rumen-degradable protein supply, ruminal NH3-N concentration, and omasal flows of N, microbial NAN, and total NAN compared with those fed the high-CP diet. Feeding the low-CP compared with the high-CP diet also resulted in lower endogenous urea-N production, urea-N recycled to the gastrointestinal tract, and urea-N excretion in urine. In summary, our results indicate that both W-DDGS and B-DDGS can be included as the major protein sources in dairy cow diets without compromising nutrient supply and production performance. However, feeding the low-CP diet lowered omasal flows of microbial protein and metabolizable protein, which, in turn, resulted in lower milk production compared with feeding the high-CP diet. PMID:23932131

Chibisa, G E; Mutsvangwa, T



Effects of a Polymer-Coated Urea Product on Nitrogen Metabolism in Lactating Holstein Dairy Cattle  

Microsoft Academic Search

ABSTRACT The purpose,of this study was to evaluate,the impact of polymer-coated urea on nitrogen retention, rumen microbial growth, and milk production and composi- tion. Coated urea (CU) that is more,slowly hydrolyzed to ammonia,than unprotected,urea could potentially be used more,efficiently by rumen,microorganisms.,Eight cows,were,offered each,of three diets in a randomized crossover,design. Each treatment,period consisted,of a 14-d adjustment,period,and,a 5-d collection,period. Diets were,formulated,to maintain,milk,production

E. Galo; S. M. Emanuele; C. J. Sniffen; J. H. White; J. R. Knapp



Regulation of Renal Urea Transport by Vasopressin  

PubMed Central

Terrestrial life would be miserable without the ability to concentrate urine. Production of concentrated urine requires complex interactions among the nephron segments and vasculature in the kidney medulla. In addition to water channels (aquaporins) and sodium transporters, urea transporters are critically important to the theories proposed to explain the physiologic processes occurring when urine is concentrated. Vasopressin (anti-diuretic hormone) is the key hormone regulating the production of concentrated urine. Vasopressin rapidly increases water and urea transport in the terminal inner medullary collecting duct (IMCD). Vasopressin rapidly increases urea permeability in the IMCD through increases in phosphorylation and apical plasma-membrane accumulation of the urea transporter A1 (UT-A1). Vasopressin acts through two cAMP-dependent signaling pathways in the IMCD: protein kinase A and exchange protein activated by cAMP Epac. Protein kinase A phosphorylates UT-A1 at serines 486 and 499. In summary, vasopressin regulates urea transport acutely by increasing UT-A1 phosphorylation and the apical plasma-membrane accumulation of UT-A1 through two cAMP-dependent pathways.

Sands, Jeff M.; Blount, Mitsi A.; Klein, Janet D.



The effect of silage and concentrate type on intake behavior, rumen function, and milk production in dairy cows in early and late lactation.  


The objective of this experiment was to evaluate the effect of feeding total mixed rations (TMR) that differ in structural and nonstructural carbohydrates to dairy cows in early and late lactation on short-term feed intake, dry matter intake (DMI), rumen fermentation variables, and milk yield. A 5 x 5 Latin square experiment with 15 dairy cows was repeated during early and late lactation. The 5 treatments were a TMR with (all on dry matter basis) 55% roughage (a 50:50 mixture of corn silage and grass silage) and 45% concentrate (a 50:50 mixture of concentrate rich in structural carbohydrates and concentrate rich in nonstructural carbohydrates; treatment CON), a TMR with the concentrate mixture and 55% grass silage (RGS) or 55% corn silage (RCS), and a TMR with the roughage mixture and 45% of the concentrate rich in structural carbohydrates (CSC) or the concentrate rich in nonstructural carbohydrates (CNS). Meal criteria, determined using the Gaussian-Gaussian-Weibull method per animal per treatment, showed an interaction between lactation stage and treatment. Feed intake behavior variables were therefore calculated with meal criteria per treatment-lactation stage combination. Differences in feed intake behavior were more pronounced between treatments differing in roughage composition than between treatments differing in concentrate composition, probably related to larger differences in chemical composition and particle size between corn silage and grass silage than between the 2 concentrates. The number of meals was similar between treatments, but eating time was greater in RGS (227 min/d) and lesser in RCS (177 min/d) than the other treatments. Intake rate increased when the amount of grass silage decreased, whereas meal duration decreased simultaneously. These effects were in line with a decreased DMI of the RGS diet vs. the other treatments, probably related to the high neutral detergent fiber (NDF) content. However, this effect was not found in CSC, although NDF content of the TMR, fractional clearance rate of NDF, and fractional degradation rate of NDF was similar between CSC and RGS. Rumen fluid pH was lesser, and molar proportions of acetic acid and of propionic acid were lesser and greater, respectively, in RCS compared with all other diets. Milk production did not differ between treatments. There was no effect of type of concentrate on milk composition, but diet RCS resulted in a lesser milk fat content and greater milk protein content than diet RGS. Lactation stage did affect short-term feed intake behavior and DMI, although different grass silages were fed during early and late lactation. The results indicate that short-term feed intake behavior is related to DMI and therefore may be a helpful tool in optimizing DMI and milk production in high-production dairy cows. PMID:19038953

Abrahamse, P A; Vlaeminck, B; Tamminga, S; Dijkstra, J



Molecular Basis of the Apparent Near Ideality of Urea Solutions.  

SciTech Connect

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. Activity coefficients of urea solutions are calculated to explore the mechanism of its solution properties, which form the basis for its well-known use as a strong protein denaturant. We perform free energy simulations of urea solutions in different urea concentrations using two urea models (OPLS and KBFF models) to calculate and decompose the activity coefficients. For the case of urea, we clarify the concept of the ideal solution in different concentration scales and standard states and its effect on our subsequent analysis. The analytical form of activity coefficients depends on the concentration units and standard states. For both models studied, urea displays a weak concentration dependence for excess chemical potential. However, for the OPLS force-field model, this results from contributions that are independent of concentration to the van der Waals and electrostatic components whereas for the KBFF model those components are nontrivial but oppose each other. The strong ideality of urea solutions in some concentration scales (incidentally implying a lack of water perturbation) is discussed in terms of recent data and ideas on the mechanism of urea denaturation of proteins.

Kokubo, Hironori; Rosgen, Jorg; Bolen, D Wayne; Pettitt, Bernard M.



A Sustainable Alternative to a U.S. Breast Milk Monitoring Program: Using NHANES Serum Data to Estimate Breast Milk PBDE Concentrations  

EPA Science Inventory

Polybrominated diphenyl ethers (PBDEs) are high-production-volume chemicals that have been widely used as flame retardants in a variety of consumer products. PBDE concentrations in the environment, wildlife, and humans have been increasing for several decades. Concentrations in t...


Milking equipment for robotic milking  

Microsoft Academic Search

A speculative approach to identifying the type of milking equipment which could be used in the developed automated milking systems of the future is described. Simple robotic milking can use conventional milking systems and equipment. New technologies from materials science to sensors and control systems can allow a radical reappraisal of the milking system with opportunities for significant changes in

J. Eric Hillerton



Ruminal metabolism of flaxseed ( Linum usitatissimum) lignans to the mammalian lignan enterolactone and its concentration in ruminal fluid, plasma, urine and milk of dairy cows.  


Secoisolariciresinol diglucoside is the main flax (Linum usitatissimum) lignan that is converted to the mammalian lignans enterodiol (ED) and enterolactone (EL) by gastrointestinal microbiota. The objectives of the present study were to investigate the role of ruminal microbiota and the effects of flax oil on in vivo metabolism of flax lignans and concentration of EL in biological fluids. Four rumen-cannulated dairy cows were used in a 4 x 4 Latin square design. There were four periods of 21 d each and four treatments utilising flax hulls (1800 g/d) and oil (400 g/d) supplements. The treatments were: (1) oil and hulls administered in the rumen and abomasal infusion of water; (2) oil and hulls administered in the abomasum; (3) oil infused in the abomasum and hulls placed in the rumen; (4) oil placed in the rumen and hulls administered in the abomasum. Samples were collected during the last week of each period and subjected to chemical analysis. The site of supplementation of oil and hulls had no effect on ruminal EL concentration. Supplementing flax oil in the rumen and the abomasum led to similar EL concentrations in urine, plasma and milk. Concentrations of EL were higher in the urine, plasma and milk of cows supplemented with hulls in the rumen than in those placed with hulls in the abomasum. The present study demonstrated that ruminal microbiota play an important role in the metabolism of flax lignans. PMID:19393113

Gagnon, Nathalie; Côrtes, Cristiano; da Silva, Daniele; Kazama, Ricardo; Benchaar, Chaouki; dos Santos, Geraldo; Zeoula, Lucia; Petit, Hélčne V



Effects of additional milk replacer feeding on calf health, growth, and selected blood metabolites in calves.  


The objective of the experiment was to evaluate effects of increased milk replacer feeding on growth, intake, feed efficiency, and health parameters in stressed calves. Holstein bull calves (n = 120; approximately 3 to 8 d of age) were purchased from sale barns and dairy farms and housed in fiberglass hutches. In addition, wood shavings contaminated with coronavirus were mixed with clean shavings and added to each hutch before the start of the experiment. Calves were fed either a fixed amount (454 g/d) of a 20% crude protein (CP), 20% fat milk replacer to weaning at 28 d or a variable amount (454, 681, 908, and 454 g/d on d 0 to 7, 8 to 14, 15 to 31, and 32 to 41, respectively) of a milk replacer containing 28% CP and 17% fat without or with added dietary supplement containing bovine serum. Calves were also fed commercial calf starter and water ad libitum. Plasma IgG concentration in most calves on arrival at the facility was < 10 g/L. Intake, change in body weight, feed efficiency, morbidity and mortality, and selected plasma metabolites were determined. Body weight at 28 d, 56 d, daily body weight gain, intake of milk replacer, fecal scores, days with diarrhea, and days treated with antibiotics were increased with feeding variable amount of milk replacer over the 56-d study. Starter intake from d 1 to 56 was reduced from 919 to 717 g/d in calves fed fixed and variable amounts of milk replacer, respectively. Morbidity, measured as the number of days that calves had diarrhea, was increased by 53% when a variable amount of milk replacer was fed. Calves fed variable milk replacer were treated with antibiotics for 3.1 d compared with 1.9 d for calves fed 454 g of milk replacer/d. Concentrations of plasma glucose, urea N, and insulin-like growth factor-I were increased when calves were fed variable amount of milk replacer. Dietary supplement containing bovine serum had no effect on any parameter measured. There was no effect of milk replacer feeding on concentrations of nonesterified fatty acids, total protein, or growth hormone concentrations. Plasma tumor necrosis factor-alpha was highest in calves with the highest plasma IgG concentrations on the day of arrival and might be related to the calf's ability to identify pathogens in the environment. Under conditions of this study, calves fed variable amount of milk replacer and exposed to immunological challenge before weaning had greater BW gain, but also increased incidence of diarrhea that required added veterinary treatments. PMID:16357284

Quigley, J D; Wolfe, T A; Elsasser, T H



Lead content of milk and infant formula  

SciTech Connect

Survey report:A survey to determine the lead content of early infant food sources was conducted in Washington, D.C. Samples were collected from various lots of national brands of infant formula and evaporated milk, cartons of nonfat dry milk, containers of homogenized cow's milk, and human milk. Mean concentrations of lead in infant formula, evaporated milk, nonfat dry milk, fresh cow's milk, and human milk were 0.135 g/ml, 0.03 g/ml, 0.01 g/ml, 0.53 g/ml, and 0.02 g/ml respectively. (2 references, 2 tables)

Walker, B.



Cluster structure in urea aqueous solution and it's effect on DNA denature  

NASA Astrophysics Data System (ADS)

The existence of large cluster structure in urea aqueous solution is proved by Small Angle Neutron Scattering (SANS). Our results indicate that urea is a water- structure-breaker, and large urea cluster will be formed when it's concentration is higher than 20 w%. This cluster is very stable, and almost do not change with temperature. The helix-to-coil denaturation transition of DNA was studied with various urea concentrations, to testify the solvent structure influence on this process.

Cheng, He; Han, Charles C.; Hammouda, Boualem



Raw Milk & Pasteurized Milk  

Center for Food Safety and Applied Nutrition (CFSAN)

... Los Riesgos de la Leche sin Pasteurizar. -. News and Events. 02/22/2012 Federal government gains permanent injunction against raw milk producer ... More results from


Variovorax sp.-mediated biodegradation of the phenyl urea herbicide linuron at micropollutant concentrations and effects of natural dissolved organic matter as supplementary carbon source.  


In nature, pesticides are often present as micropollutants with concentrations too low for efficient biodegradation and growth of heterotrophic pollutant-degrading bacteria. Instead, organic carbon present in environmental dissolved organic matter (eDOM) constitutes the main carbon source in nature. Information on how natural organic carbon affects degradation of pollutants and micropollutants, in particular, is however poor. Linuron-degrading Variovorax sp. strains SRS16, WDL1, and PBLH6 and a triple-species bacterial consortium, from which WDL1 originated, were examined for their ability to degrade linuron at micropollutant concentrations and the effect hereon of different eDOM formulations of varying biodegradability as supplementary C-source was explored. Individual strains and the consortium degraded linuron at initial concentrations as low as 1 ?g?L(-1) till concentrations below 4 ng?L(-1). Degradation kinetics differed among strains with rates that differed up to 70-fold at the lowest linuron concentrations and with lag phases ranging from 0 to 7 days. Linuron biodegradation by the individual strains was inhibited by an easily biodegradable compound such as citrate but stimulated by eDOM at a linuron concentration of 10 mg?L(-1). Effects were strongly reduced or became non-existent at micropollutant linuron concentrations. Effects of eDOM on degradation at 10 mg?L(-1) linuron by WDL1 were reduced when WDL1 was incubated together with its original consortium members. This is the first report on eDOM effects on degradation of pesticides at micropollutant concentrations and indicates these effects are limited and depend on linuron and eDOM concentrations, eDOM quality, and the bacterial culture. PMID:23339013

Horemans, Benjamin; Vandermaesen, Johanna; Vanhaecke, Lynn; Smolders, Erik; Springael, Dirk



Effects of shearing on milk yields and milk composition in machine-milked Dorset ewes  

Microsoft Academic Search

Four experiments were conducted to determine the effects of shearing before lambing or during lactation on the yield and composition of milk from machine-milked Dorset ewes. In Experiments 1 and 2, ewes were shorn in early lactation and although no effects on milk yield were recorded, there were significant increases (8–24%) in the concentrations of fat and protein in the

T. W. Knight; R. Bencini; N. A. Haack; A. F. Death



Chemiresistor urea sensor  


A sensor to detect and quantify urea in fluids resulting from hemodialysis procedures, and in blood and other body fluids. The sensor is based upon a chemiresistor, which consists of an interdigitated array of metal fingers between which a resistance measured. The interdigitated array is fabricated on a suitable substrate. The surface of the array of fingers is covered with a coating containing the enzyme urease which catalyzes the hydrolysis of urea to form the ammonium ion, the bicarbonate ion, and hydroxide-chemical products which provide the basis for the measured signal. In a typical application, the sensor could be used at bedside, in conjunction with an appropriate electronics/computer system, in order to determine the hemodialysis endpoint. Also, the chemiresistor used to detect urea, can be utilized with a reference chemiresistor which does not contain urease, and connected in a differential measurement arrangement, such that the reference chemiresistor would cancel out any fluctuations due to background effects.

Glass, Robert S. (Livermore, CA)



Effects of forage type, forage to concentrate ratio, and crushed linseed supplementation on milk fatty acid profile in lactating dairy cows  

Microsoft Academic Search

The effects of an increasing proportion of crushed\\u000alinseed (CL) in combination with varying forage type\\u000a(grass or corn silage) and forage to concentrate ratio\\u000a(F:C), and their interactions on milk fatty acid (FA)\\u000aprofile of high-producing dairy cows was studied using\\u000aa 3-factor Box-Behnken design. Sixteen Holstein\\u000aand 20 Swedish Red cows were blocked according to\\u000abreed, parity, and

A. E. Sterk; B. E. O. Johansson; H. Z. H. Taweel; M. Murphy; A. M. van Vuuren; W. H. Hendriks; J. Dijkstra



Effect of Dietary Forage Concentration and Buffer Addition on Duodenal Flow of Trans-C18:1 Fatty Acids and Milk Fat Production in Dairy Cows[1] and [2  

Microsoft Academic Search

Milk fat depression in cows fed high grain diets has been shown to be related to increased trans-C18:1 fatty acids in milk. Trans-C18:1 fatty acids are produced as a result of incomplete biohydrogenation of dietary polyunsaturated fatty acids in the rumen. The objec- tive of this study was to determine the effects of varying amounts of dietary concentrate and buffer

K. F. Kalscheur; B. B. Teter; L. S. Piperova; R. A. Erdman



Effect of the level and type of starchy concentrate on tissue lipid metabolism, gene expression and milk fatty acid secretion in Alpine goats receiving a diet rich in sunflower-seed oil.  


The potential benefits on human health have prompted an interest in developing nutritional strategies for reducing saturated and increasing specific unsaturated fatty acids (FA) in ruminant milk. The impact of the level and type of starchy concentrate added to diets supplemented with sunflower-seed oil on caprine milk FA composition and on mammary, omental and perirenal adipose, and liver lipid metabolism was examined in fourteen Alpine goats in a replicated 3 × 3 Latin square with 21 d experimental periods. Treatments were a grass hay-based diet with a high level of forage (F) or a high level of concentrate with either maize grain (CM) or flattened wheat (CW) as source of starch and supplemented with 130 g/d sunflower-seed oil. Milk yield was enhanced (P<0·01) and milk fat content was decreased on the CM and CW diets compared with the F diet, resulting in similar milk fat secretion. Both high-concentrate diets increased (P<0·05) milk yield of 10 : 0-16 : 0 and decreased trans-9,11-18 : 1 and cis-9, trans-11-18 : 2. The CW diet decreased (P<0·05) the output of ?C18 and ?cis-18 : 1 and increased (P<0·05) the output of trans-10-18 : 1 in milk. The expression and/or activity of fourteen proteins involved in the major lipogenic pathways in mammary tissues and of lipogenic genes in adipose and liver tissues were similar among treatments. In conclusion, high starch concentrates alter milk FA yield via mechanisms independent of changes in mammary, liver or adipose tissue lipogenic gene expression. Furthermore, data provided indications that mammary lipogenic responses to starch-rich diets differ between caprine and bovine ruminants. PMID:21875448

Bernard, L; Leroux, C; Rouel, J; Bonnet, M; Chilliard, Y



Penicillin concentrations in serum, milk, and urine following intramuscular and subcutaneous administration of increasing doses of procaine penicillin G in lactating dairy cows.  

PubMed Central

Eight healthy, non-pregnant, crossbred Holstein dairy cows (557-682 kg) within their first 3 months of lactation (13-21.5 kg of milk/day) were used. Cows were kept in tie stalls for the whole experiment. The 8 cows were randomly assigned to 2 (IM and SC) 4 x 4 balanced Latin square design experiments. Doses of procaine penicillin G (PPG) (300000 IU/mL) in each square were 7000, 14000, 21000 and 28000 IU/kg and were injected IM or SC once daily for 5 consecutive days. Volumes of PPG per site of injection never exceeded 20 mL. Blood was collected to determine the Cmax, Tmax, and AUC; urine and milk were also taken to measure the persistence of PPG in these fluids. Results show that serum Cmax and Tmax were only slightly affected by increasing the doses or the route of administration, whereas the AUC was linearly increased in relation to the dose injected in both modes of injection. In the urine, Cmax varied from 160 to 388 IU/mL and Tmax from 72-120 h during 5 consecutive days of PPG injection. A dose effect in Cmax was observed only for the IM route of administration and no variation (P > 0.05) was found between the IM and SC routes. Milk Cmax concentrations were only increased by the dose regimen in the IM group. At doses of 21000 and 28000 IU/kg, the IM group had a higher (P > 0.05) Cmax when compared with the SC groups. Milk PPG residues were not detectable over 96 h following the last IM injection, independently of the dose injected. However milk PPG residues were detected for up to 132 h following the last SC injection. These results show that when PPG is injected IM once daily in volumes not exceeding 20 mL/site at doses as high as 28000 IU/kg, the withdrawal period should be at least 96 h. Therefore, in the present model, there was no advantage to inject PPG by SC route to improve PPG kinetic parameters as the AUC, Cmax, or Tmax.

Dubreuil, P; Daigneault, J; Couture, Y; Guay, P; Landry, D



Reductive alkylation of urea: A practical route to substituted ureas  

Microsoft Academic Search

Conditions are disclosed for the formation of either mono- or di-substituted ureas by reductive alkylation, which are readily adaptable to large scale preparations. Dehydrating agents such as acetyl chloride or trimethylsilyl chloride effectively promote the condensation of ureas and aldehydes. Reduction of the adducts affords the mono- or di-substituted ureas in high yields.

Daqiang Xu; Lech Ciszewski; Tangqing Li; Olijan Repi?; Thomas J. Blacklock



Crystal structure of a bacterial homologue of the kidney urea transporter  

SciTech Connect

Urea is highly concentrated in the mammalian kidney to produce the osmotic gradient necessary for water re-absorption. Free diffusion of urea across cell membranes is slow owing to its high polarity, and specialized urea transporters have evolved to achieve rapid and selective urea permeation. Here we present the 2.3 {angstrom} structure of a functional urea transporter from the bacterium Desulfovibrio vulgaris. The transporter is a homotrimer, and each subunit contains a continuous membrane-spanning pore formed by the two homologous halves of the protein. The pore contains a constricted selectivity filter that can accommodate several dehydrated urea molecules in single file. Backbone and side-chain oxygen atoms provide continuous coordination of urea as it progresses through the filter, and well-placed {alpha}-helix dipoles provide further compensation for dehydration energy. These results establish that the urea transporter operates by a channel-like mechanism and reveal the physical and chemical basis of urea selectivity.

Levin, Elena J.; Quick, Matthias; Zhou, Ming; (Columbia)



Effect of toasting field beans and of grass-clover: Maize silage ratio on milk production, milk composition and sensory quality of milk  

Microsoft Academic Search

The effect of toasting field beans and of grass-clover: maize silage ratio on milk production, milk composition and the sensory quality of the milk was investigated in a 2?2 factorial experiment. Toasting of field beans resulted in lower milk contents of both fat (44.2 versus 46.1g\\/kg, P=0.02) and protein (33.5 versus 34.2g\\/kg, P=0.008), whereas milk production, urea and somatic cell

Lisbeth Mogensen; Jannie Steensig Vestergaard; Xavier Fretté; Peter Lund; Martin Riis Weisbjerg; Troels Kristensen



Urea Process Analytical Study.  

National Technical Information Service (NTIS)

In an effort to help determine the feasibility of the Urea process for production of the amine fuels, AFRPL established an in-house program to develop a useful analytical technique for monitoring the critical DMU to UDMH reaction. It was the absence of su...

L. A. Dee S. G. Wax



Evolutionary aspects of urea utilization by fungi  

PubMed Central

The higher fungi exhibit a dichotomy with regard to urea utilization. The hemiascomycetes use urea amidolyase (DUR1,2) whereas all other higher fungi use the nickel-containing urease. Urea amidolyase is an energy dependent biotin-containing enzyme. It likely arose prior to the Euascomycete/Hemiascomycete divergence ca. 350 million years ago by insertion of an unknown gene into one copy of a duplicated methylcrotonyl CoA carboxylase (MccA). The dichotomy between urease and urea amidolyase coincides precisely with that for the Ni/Co transporter (Nic1p) which is present in the higher fungi that use urease and absent in those that do not. We suggest that the selective advantage for urea amidolyase is that it allowed the hemiascomycetes to jettison all Ni2+ and Co2+ dependent metabolism and thus to have two fewer transition metals whose concentrations need to be regulated. Also, the absence of MccA in the hemiascomycetes coincides with and may explain their production of fusel alcohols.

Navarathna, Dhammika H.M.L.P.; Harris, Steven D.; Roberts, David D.; Nickerson, Kenneth W.



Effect of adding a mycotoxin-sequestering agent on milk aflatoxin M? concentration and the performance and immune response of dairy cattle fed an aflatoxin B?-contaminated diet.  


This project aimed to examine the effects of adding 2 doses of a montmorillonite-based mycotoxin adsorbent on milk aflatoxin M(1) (AFM(1)) concentrations and the performance and innate immune response of dairy cows fed an aflatoxin B(1) (AFB(1))-contaminated diet. Eight lactating cows were used in a duplicated 4×4 Latin square design with 12-d periods. Treatments included the following: (1) control diet (C), (2) aflatoxin diet (T) containing C and 75 µg of AFB(1)/kg, 3) low-clay (LC) diet containing T and Calibrin A (Amlan International, Chicago, IL) added at 0.2% of the diet dry matter (DM), and 4) high-clay diet (HC) containing T and Calibrin A added at 1% of the diet DM. Milk production and DM intake were recorded daily and milk was sampled twice daily on d 5, 9, 10, 11, and 12 in each period. Blood samples were collected on d 5 and 9 of each period. Dietary treatments did not affect DM intake, milk yield, or feed efficiency. Even though cows were limit fed, feeding T instead of C reduced milk fat yield (0.67 vs. 0.74 kg/d) and milk protein concentration (3.28 vs. 3.36%). Concentrations of AFM(1) in milk of cows fed the T and LC diets were similar (0.57 and 0.64 µg/kg) and greater than those of cows fed the HC diet (0.46 µg/kg). Haptoglobin concentration was greater (22.0 vs. 14.4) and ?(2)-integrin expression (220 vs. 131) tended to be greater in cows fed diet T instead of C, but values for cows fed LC, HC, and C did not differ. In comparison to C, feeding T increased the innate immune response and decreased milk fat yield and milk protein concentration, but feeding LC and HC did not affect these measures. Only the HC diet reduced milk AFM(1) concentration. PMID:22901480

Queiroz, O C M; Han, J H; Staples, C R; Adesogan, A T



[Irreversible inactivation of Chlorella glutamine synthetase by urea].  


The effect of urea on Chlorella glutamine synthetase (E. C. activity and tertiary structure is investigated. Urea is found to inhibit the activity of glutamine synthetase, the inhibitory effect being independent on the time. The enzyme molecule relax and changes its affinity to ammonium under the effect of urea at concentrations of 1.0-4.0 M. Higher concentrations of urea (5,0 M and more) produce a dissociation of the enzyme molecule into monomers without any intermediate forms. Monomers do not possess any synthetase and transferase activities. Substrates and cofactors do not protect the enzyme from the effect of urea and do not stimulate the emzyme reactivation and reaggregation after its dissotiation. The data obtained are discussed from the viewpoint of the regulation of Chlorella glutamine synthetase activity in vivo. PMID:26431

Rasulov, A S; Evstigneeva, Z G; Kretovich, W L



Reversible inhibition of urea exchange in rat hepatocytes.  

PubMed Central

Urea exchange is enhanced in renal collecting duct cells and erythrocytes by transporters which can be inhibited by phloretin and urea analogs such as thiourea. In this study, evidence for a comparable transporter was found in rat livers perfused with solutions which contained no red cells and in suspensions of hepatocytes. Bolus injections containing 125I-albumin (intravascular indicator), 99mTc-DTPA (extracellular indicator), 3HOH (water indicator), and [14C]urea were administered into the portal vein and fluid was collected from the hepatic vein. Under control conditions, [14C]urea and 3HOH emerged from the hepatic vein at nearly the same rate. However when the perfusate contained 2.5 mM phloretin (equivalent to 0.058 mM phloretin not bound to albumin), the amount of [14C]urea which had been recovered in the hepatic venous outflow by the time of peak 125I-albumin concentrations exceeded 3HOH recovery by a factor of 2.31 +/- 0.23 (n = 7). When the perfusate contained 200 mM thiourea, the comparable recovery of [14C]urea from the hepatic veins exceeded that of 3HOH by a factor of 3.48 +/- 0.44 (n = 7). These effects were at least partially reversible and suggested inhibition of urea transporters in hepatocytes. This conclusion was supported by studies of unloading of [14C]urea from hepatocytes which were exposed to unlabeled solutions: in the presence of phloretin, the amount of [14C]urea remaining within hepatocytes at 4 s was approximately twice that remaining in hepatocytes which had not been exposed to phloretin. Rapid transport of urea out of hepatocytes may increase urea synthesis and minimize cellular swelling due to urea accumulation.

Effros, R M; Jacobs, E; Hacker, A; Ozker, K; Murphy, C



The Protein and Non-Protein Nitrogen Fractions in Milk. I. Methods of Analysis1  

Microsoft Academic Search

While the major part of the nitrogen in milk is accounted by casein, albumin, globulin and proteoses-peptones, milk also contains nitrogen in the form of am- monia, urea, creatinine, creatine, uric acid and amino acids, and mere traces in the form of vitamins, enzymes, phospholipids and cerebrosides. The non-pro- tein nitrogen components of milk have not been studied extensively. They

K. M. Shahani; H. H. Sommer



Migration of plasticizer from poly(vinyl chloride) milk tubing  

Microsoft Academic Search

Milk samples were collected from a dairy in Norway at various stages of the milking process in order to assess the extent of migration of di(2?ethyl hexyl)phthalate (DEHP) from plasticized tubing used in commercial milking equipment. In control milk samples obtained by hand milking, DEHP contamination was below 5 ?g\\/kg, whilst for machine milking, concentrations in the milking chamber for

L. Castle; J. Gilbert; T. Eklund



Assessment of dialysis adequacy using the dialysate urea monitor: preliminary experience of the dialysate urea monitor.  


Numerous studies have identified a strong linkage between the delivered dialysis dose (Kt/V) and the survival of hemodialysis (HD) patients. However, the current method used to calculate Kt/V requires multiple blood samples and the process is complex and time consuming. We evaluate the performance of a recently developed on-line monitor (Biostat 1000 dialysate urea monitor, Baxter) that measures the urea concentration in the effluent dialysate and displays Kt/V and nPCR immediately after hemodialysis. To verify the performance of the urea monitor, we selected 21 hemodialysis patients, calculated their Kt/V and nPCR values from blood samples obtained during each hemodialysis, and compared the results with data obtained using the urea monitor. The Kt/V and nPCR values calculated by the urea monitor were both significantly correlated with those obtained using blood samples (R = 0.804, p < 0.001 in Kt/V and R = 0.749, p < 0.001 in nPCR). Our results suggest that the urea monitor may be used for on-line assessment of dialysis adequacy and obviates the need for blood sampling. PMID:9415936

Lee, W C; Tsai, C J; Huang, C C; Lee, C C; Chien, Y S; Hu, S A; Wu, C H



A structural basis for the interaction of urea with lysozyme.  

PubMed Central

The effect of urea on the crystal structure of hen egg-white lysozyme has been investigated using X-ray crystallography. High resolution structures have been determined from crystals grown in the presence of 0, 0.7, 2, 3, 4, and 5 M urea and from crystals soaked in 9 M urea. All the forms are essentially isomorphous with the native type II crystals, and the derived structures exhibit excellent geometry and RMS differences from ideality in bond distances and angles. Comparison of the urea complex structures with the native enzyme (type II form, at 1.5 A resolution) indicates that the effect of urea is minimal over the concentration range studied. The mean difference in backbone conformation between the native enzyme and its urea complexes varies from 0.18 to 0.49 A. Conformational changes are limited to flexible surface loops (Thr 69-Asn 74, Ser 100-Asn 103), the active site loop (Asn 59-Cys 80), and the C-terminus (Cys 127-Leu 129). Urea molecules are bound to distinct sites on the surface of the protein. One molecule is bound to the active site cleft's C subsite, at all concentrations, in a fashion analogous to that of the N-acetyl substituent of substrate and inhibitor sugars normally bound to this site. Occupation of this subsite by urea alone does not appear to induce the conformational changes associated with inhibitor binding.

Pike, A. C.; Acharya, K. R.



Urearetics: a small molecule screen yields nanomolar potency inhibitors of urea transporter UT-B  

Microsoft Academic Search

Functional studies in knockout mice in- dicate a critical role for urea transporters (UTs) in the urinary concentrating mechanism and in renal urea clearance. However, potent and specific urea transport blockers have not been available. Here, we used high- throughput screening to discover high-affinity, small molecule inhibitors of the UT-B urea transporter. A collection of 50,000 diverse, drug-like compounds was

Marc H. Levin; Ricardo de la Fuente; A. S. Verkman



Clinico-pathological findings in peripartum dairy cows fed anion salts lowering the dietary cation-anion difference: involvement of serum inorganic phosphorus, chloride and plasma estrogen concentrations in milk fever.  


In our previous study, it was demonstrated that the administration of anion salts, which slightly lower the dietary cation-anion difference (DCAD), in the prepartum period is safe and effective for preventing milk fever in multiparous cows. In the present study, several clinico-pathological constituents in serum and urine, which might be related to milk fever, were analyzed using stored samples from the previous study to identify clinico-pathological parameters for easily evaluating the efficacy of lowering DCAD and to further investigate the mechanism by which lowering DCAD prevents milk fever. Among the parameters analyzed in the present study, inorganic phosphorus (iP) was involved in milk fever because the serum concentration and urinary excretion of iP were significantly higher in the group of primiparous cows (heifer group), which did not develop hypocalcemia, than those in other groups of multiparous cows. Serum chloride concentrations in the heifer group and the group of multiparous cows fed anion salts (anion group) tended to remain higher than those in other control groups of multiparous cows suggesting that serum chloride concentration may be utilized for evaluating the status of metabolic acidosis and the efficacy of lowerng DCAD in dairy cows fed anion salts. In addition, plasma estradiol-17beta concentration in the heifer group tended to be lower at parturition compared with that in other multiparous groups suggesting that estrogen known as a potent inhibitor of bone resorption may be involved in developing milk fever. PMID:17596033

Kurosaki, Naotoshi; Yamato, Osamu; Sasamoto, Yoshihiko; Mori, Fuminobu; Imoto, Seiichi; Kojima, Toshiyuki; Yamasaki, Masahiro; Maede, Yoshimitsu



Quinine and Urea  

NSDL National Science Digital Library

The WebWare molecules of the month are discussed in two laboratory articles in this issue. Quinine is studied in the article "A Fluorimetric Approach to Studying the Effects of Ionic Strength on Reaction Rates: An Undergraduate Steady-State Fluorescence Laboratory Experiment" by Stephen W. Bigger, Peter J. Watkins, and Bruce Verity. Urea, a typical protein denaturant, is used as a cosolvent in the article "Transfer Free Energy and the Hydrophobic Effect" by Joseph M. Serafin.


Milk Allergy  


... to find out. What Happens With a Milk Allergy? Food allergies involve the body's immune system, which ... Continue How Can Doctors Tell It's a Milk Allergy? If your doctor suspects you might have a ...


Theoretical study on the structures and properties of mixtures of urea and choline chloride.  


In this work, we investigated in detail the structural characteristics of mixtures of choline chloride and urea with different urea contents by performing molecular dynamic (MD) simulations, and offer possible explanations for the low melting point of the eutectic mixture of choline chloride and urea with a ratio of 1:2. The insertion of urea molecules was found to change the density distribution of cations and anions around the given cations significantly, disrupting the long-range ordered structure of choline chloride. Moreover, with increasing urea concentration, the hydrogen bond interactions between choline cations and Cl(-) anions decreased, while those among urea molecules obviously increased. From the hydrogen bond lifetimes, it was found that a ratio of 1:2 between choline chloride and urea is necessary for a reasonable strength of hydrogen bond interaction to maintain the low melting point of the mixture of choline chloride with urea. In addition, it was also deduced from the interaction energies that a urea content of 67.7 % may make the interactions of cation-anion, cation-urea and anion-urea modest, and thus results in the lower melting point of the eutectic mixture of choline chloride and urea. The present results may offer assistance to some extent for understanding the physicochemical properties of the eutectic mixture of choline chloride and urea, and give valuable information for the further development and application of deep eutectic solvents. PMID:23435478

Sun, Hui; Li, Yan; Wu, Xue; Li, Guohui



Effects of dietary forage sources on rumen microbial protein synthesis and milk performance in early lactating dairy cows.  


The objective of this study was to evaluate the effects of dietary forage sources on milk performance, rumen microbial protein synthesis, and N utilization in early lactation dairy cows. Twelve primiparous Chinese Holstein dairy cows (45 ± 6.0 DIM) were used in a 3 × 3 Latin square design. Diets were isonitrogenous and isocaloric, with a forage-to-concentrate ratio of 45:55 [dry matter (DM) basis] and contained similar concentrate mixtures. Different forage sources were then added (on a DM basis): 21% corn silage, 19% corn stover, and 5% alfalfa hay (CS); 19% corn silage, 21% Chinese wild rye hay and 5% alfalfa hay (CWR); or 19% corn silage, 9% Chinese wild rye hay, and 17% alfalfa hay (AH). Each period lasted for 21 d, with the first 14 d for an adaptation period. Dry matter intake was not affected by the source of dietary forage. Milk yield was higher for cows fed AH than those fed CS, with an intermediate value for CWR. Milk protein content was higher in the cows fed AH compared with CWR (3.02 vs. 2.92%), with CS (2.95%) at an intermediate position. The contents of milk fat and lactose were not different among the treatments. However, milk efficiency (milk yield/DM intake) was higher for cows fed AH than those fed CS, with those fed CWR intermediate. Cows fed AH had higher microbial protein yield and metabolizable protein than those fed CS or CWR. The concentrations of urea N in the urine, blood, and milk were decreased for cows fed AH, indicating an increased N conversion. The results indicated that corn stover could replace Chinese wild rye grass in the diets for lactating cows and that a high proportion of alfalfa hay in the diet is beneficial for milk protein production by increasing microbial protein yield. This can be attributed to the improving the supply of rumen-available energy. PMID:23295118

Zhu, W; Fu, Y; Wang, B; Wang, C; Ye, J A; Wu, Y M; Liu, J-X



Effect of dietary carbohydrate composition and availability on utilization of ruminal ammonia nitrogen for milk protein synthesis in dairy cows.  


A trial with four ruminally and duodenally cannulated, late-lactation dairy cows was conducted to investigate the effect of dietary carbohydrate (CHO) composition and availability on ruminal ammonia N utilization and transfer into milk protein. Two diets were fed at 8-h intervals in a crossover design. The diets differed in CHO composition: the ruminally fermentable non-structural carbohydrates (RFSS) diet (barley and molasses) contained a larger proportion of ruminally available CHO in the nonstructural carbohydrate fractions and the ruminally fermentable fiber (RFNDF) diet (corn, beet pulp, and brewer's grains) contained a larger proportion of CHO in ruminally available fiber. Nitrogen-15 was used to label ruminal ammonia N and consequently microbial and milk N. Fermentation acids, enzyme activities, and microbial protein production in the rumen were not affected by diet. Ruminal ammonia concentration was lowered by RFNDF. Ruminal and total tract digestibility of nutrients did not differ between diets except that apparent ruminal degradability of crude protein was lower for RFNDF compared with RFSS. Partitioning of N losses between urine and feces was also not affected by diet. Milk yield and fat and protein content were not affected by treatment. Average concentration of milk urea N was lower for RFNDF than for RFSS. Proportion of milk protein N originating from ruminal microbial N (based on the areas under the 15N-enrichment curves) was higher for RFNDF than for RFSS. Cumulative recovery of 15N in milk protein was 13% higher for RFNDF than for RFSS indicating enhanced transfer of 15N-ammonia into milk protein with the former diet. The results suggested that, compared to diets containing higher levels of ruminally fermentable starch, diets providing higher concentration of ruminally fermentable fiber may enhance transfer of ruminal ammonia and microbial N into milk protein. PMID:12906060

Hristov, A N; Ropp, J K



Activity of adventitious Enterococcus strains on model curdled caprine milk: microbial growth and evolution of concentration of organic acids and lactose throughout time.  


Enterococci offer a few unique advantages when compared with other lactic acid bacteria in that they are resistant to phages, stable lactose fermenters, tolerant to relatively high concentrations of sodium chloride and optimal growers at relatively high temperatures (Franz et al., 1999). Such genus occurs and grows in a variety of cheeses, especially artisanal cheeses produced in Southern Europe usually from raw milk; they are claimed to play a major role in ripening and aroma development in such cheeses (Freitas et al., 1995; Macedo et al., 1995). Enterococci can produce lactic, acetic, propionic and succinic acids (Ocando et al., 1994), compounds that have been correlated with flavor characteristics of cheese; hence strains of Enterococcus have been successfully used as starters for different cheese (Franz et al., 1999). PMID:15954666

Pintado, M E; Santos, C C; Malcata, F X



Effects of progesterone and human chorionic gonadotrophin administration five days postinsemination on plasma and milk concentrations of progesterone and pregnancy rates of normal and repeat breeder dairy cows.  

PubMed Central

Treatment with a progesterone-releasing intravaginal device between days 5 and 12 after estrus elevated (p less than 0.05) plasma progesterone concentrations between days 6 and 8 in comparison with controls. Treatment with injectable progesterone (200 mg) on days 5, 7, 9 and 11 postestrus did not increase plasma progesterone concentrations over controls. The administration of 1500 IU human chorionic gonadotrophin (hCG) on day 5 after estrus resulted in a sustained increase (p less than 0.01) in plasma progesterone concentrations from day 8 until day 20 when measurements ceased. Pregnancy rates, as a result of artificial insemination (AI) at the pretreatment estrus, in these treatments (n = 12-14 each), were unaffected by any of the treatments and ranged from 57.1 to 75.0% at 45-60 days post-AI. In a field trial, of 36 repeat breeder cows treated with 1500 IU hCG 5.5 days after insemination, 47.2% were pregnant at 60 days, whereas 39.5% of saline-treated controls were diagnosed pregnant. Treatment with hCG significantly (p less than 0.05) increased milk progesterone concentrations over controls on days 14 and 20 after insemination.

Walton, J S; Halbert, G W; Robinson, N A; Leslie, K E



Effects of milk casein-derived peptides on absolute oxyhaemoglobin concentrations in the prefrontal area and on work efficiency after mental stress loading in male students.  


This study examined the influence of milk casein-derived peptides on cerebral activity after mental stress loading. In a crossover study, 16 male students were given a drink containing peptides (peptide group), or water (control group) before stress loading. The oxyhaemoglobin (HbO(2)) concentration in the prefrontal area of the brain and work efficiency were measured as indicators of cerebral activity and differences in these parameters were examined according to type A or type B personality. Type A behaviour was defined as: aggression-hostility, hard-driving-time-urgency and speed-power, whereas type B behaviour did not have these characteristics. Peptide intake resulted in a significant increase in both HbO(2) concentration and work efficiency, whilst a similar increase was not seen in the control group. When divided into type A or type B personality, the changes in HbO(2) concentration for the control group differed significantly in the right prefrontal area. Moreover, in type A subjects the HbO(2) concentration in the right prefrontal area following intake was significantly different between the peptide and control groups. PMID:18652758

Nakamura, H; Iwamoto, M; Ogata, T; Washida, K; Sekine, K; Takase, M; Park, B J; Morikawa, T; Miyazaki, Y


Interaction of molasses and monensin in alfalfa hay- or corn silage-based diets on rumen fermentation, total tract digestibility, and milk production by Holstein cows.  


Sugar supplementation can stimulate rumen microbial growth and possibly fiber digestibility; however, excess ruminal carbohydrate availability relative to rumen-degradable protein (RDP) can promote energy spilling by microbes, decrease rumen pH, or depress fiber digestibility. Both RDP supply and rumen pH might be altered by forage source and monensin. Therefore, the objective of this study was to evaluate interactions of a sugar source (molasses) with monensin and 2 forage sources on rumen fermentation, total tract digestibility, and production and fatty acid composition of milk. Seven ruminally cannulated lactating Holstein cows were used in a 5 x 7 incomplete Latin square design with five 28-d periods. Four corn silage diets consisted of 1) control (C), 2) 2.6% molasses (M), 3) 2.6% molasses plus 0.45% urea (MU), or 4) 2.6% molasses plus 0.45% urea plus monensin sodium (Rumensin, at the intermediate dosage from the label, 16 g/909 kg of dry matter; MUR). Three chopped alfalfa hay diets consisted of 1) control (C), 2) 2.6% molasses (M), or 3) 2.6% molasses plus Rumensin (MR). Urea was added to corn silage diets to provide RDP comparable to alfalfa hay diets with no urea. Corn silage C and M diets were balanced to have 16.2% crude protein; and the remaining diets, 17.2% crude protein. Dry matter intake was not affected by treatment, but there was a trend for lower milk production in alfalfa hay diets compared with corn silage diets. Despite increased total volatile fatty acid and acetate concentrations in the rumen, total tract organic matter digestibility was lower for alfalfa hay-fed cows. Rumensin did not affect volatile fatty acid concentrations but decreased milk fat from 3.22 to 2.72% in corn silage diets but less in alfalfa hay diets. Medium-chain milk fatty acids (% of total fat) were lower for alfalfa hay compared with corn silage diets, and short-chain milk fatty acids tended to decrease when Rumensin was added. In whole rumen contents, concentrations of trans-10, cis-12 C(18:2) were increased when cows were fed corn silage diets. Rumensin had no effect on conjugated linoleic acid isomers in either milk or rumen contents but tended to increase the concentration of trans-10 C(18:1) in rumen samples. Molasses with urea increased ruminal NH(3)-N and milk urea N when cows were fed corn silage diets (6.8 vs. 11.3 and 7.6 vs. 12.0 mg/dL for M vs. MU, respectively). Based on ruminal fermentation characteristics and fatty acid isomers in milk, molasses did not appear to promote ruminal acidosis or milk fat depression. However, combinations of Rumensin with corn silage-based diets already containing molasses and with a relatively high nonfiber carbohydrate:forage neutral detergent fiber ratio influenced biohydrogenation characteristics that are indicators of increased risk for milk fat depression. PMID:19109286

Oelker, E R; Reveneau, C; Firkins, J L



Studies of human milk relevant to milk banking.  


Issues regarding the efficacy of feeding human milk to premature infants include the development of optimal protocols for collecting, storing, and processing human milk. Studies of the nutritional and immunologic composition of milk produced by women who delivered term or premature infants and who weaned their infants gradually from human milk have been studied to identify optimal donors. The effects of specific collection, storage, and processing conditions on the composition of mature human milk also have been evaluated. Collection, storage, and processing conditions have distinct effects on specific functional components. The caloric content of milk, the content of nutrients carried in the lipid portion of milk, and selected enzymatic activities depend on the completeness with which the breast is emptied. Storing milk in polyethylene, polypropylene, and pyrex containers influences key immunologic components in human milk as do storage temperatures. None of the nutrient compositions of milks studied matched current estimates of the nutritional needs of premature infants. Importantly, both the concentrations and the pattern of change in nutrient and immunologic contents are distinct in milks of women delivering infants at term or prematurely. Further changes are seen during the process of gradual weaning. PMID:6470353

Garza, C; Nichols, B L



Compound Heterozygous Mutations in SLC30A2/ZnT2 Results in Low Milk Zinc Concentrations: A Novel Mechanism for Zinc Deficiency in a Breast-Fed Infant  

PubMed Central

Zinc concentrations in breast milk are considerably higher than those of the maternal serum, to meet the infant's requirements for normal growth and development. Thus, effective mechanisms ensuring secretion of large amounts of zinc into the milk operate in mammary epithelial cells during lactation. ZnT2 was recently found to play an essential role in the secretion of zinc into milk. Heterozygous mutations of human ZnT2 (hZnT2), including H54R and G87R, in mothers result in low (>75% reduction) secretion of zinc into the breast milk, and infants fed on the milk develop transient neonatal zinc deficiency. We identified two novel missense mutations in the SLC30A2/ZnT2 gene in a Japanese mother with low milk zinc concentrations (>90% reduction) whose infant developed severe zinc deficiency; a T to C transition (c.454T>C) at exon 4, which substitutes a tryptophan residue with an arginine residue (W152R), and a C to T transition (c.887C>T) at exon 7, which substitutes a serine residue with a leucine residue (S296L). Biochemical characterization using zinc-sensitive DT40 cells indicated that the W152R mutation abolished the abilities to transport zinc and to form a dimer complex, indicating a loss-of-function mutation. The S296L mutation retained both abilities but was extremely destabilized. The two mutations were found on different alleles, indicating that the genotype of the mother with low milk zinc was compound heterozygous. These results show novel compound heterozygous mutations in the SLC30A2/ZnT2 gene causing zinc deficiency in a breast-fed infant.

Itsumura, Naoya; Inamo, Yasuji; Okazaki, Fumiko; Teranishi, Fumie; Narita, Hiroshi; Kambe, Taiho; Kodama, Hiroko



Final report of the safety assessment of Urea.  


Although Urea is officially described as a buffering agent, humectant, and skin-conditioning agent-humectant for use in cosmetic products, there is a report stating that Urea also is used in cosmetics for its desquamating and antimicrobial action. In 2001, the Food and Drug Administration (FDA) reported that Urea was used in 239 formulations. Concentrations of use for Urea ranged from 0.01% to 10%. Urea is generally recognized as safe by FDA for the following uses: side-seam cements for food contact; an inhibitor or stabilizer in pesticide formulations and formulations applied to animals; internal sizing for paper and paperboard and surface sizing and coating of paper and paper board that contact water-in-oil dairy emulsions, low-moisture fats and oils, moist bakery products, dry solids with surface containing no free fats or oil, and dry solids with the surface of fat or oil; and to facilitate fermentation of wine. Urea is the end product of mammalian protein metabolism and the chief nitrogenous compound of urine. Urea concentrations in muscle, liver, and fetuses of rats increased after a subcutaneous injection of Urea. Urea diffused readily through the placenta and into other maternal and fetal organs. The half-life of Urea injected into rabbits was on the order of several hours, and the reutilization rate was 32.2% to 88.8%. Urea given to rats by a bolus injection or continuous infusion resulted in distribution to the following brain regions: frontal lobe, caudate nucleus, hippocampus, thalamus plus hypothalamus, pons and white matter (corpus callosum). The permeability constant after treatment with Urea of whole skin and the dermis of rabbits was 2.37 +/- 0.13 (x 10(6)) and 1.20 +/- 0.09 (x10(3)) cm/min, respectively. The absorption of Urea across normal and abraded human skin was 9.5% +/- 2.3% and 67.9% +/- 5.6%, respectively. Urea increased the skin penetration of other compounds, including hydrocortisone. No toxicity was observed for Urea at levels as high as 2000 mg/kg in acute oral studies using female rats or mice. No signs of toxicity were observed in male piglets dosed orally with up to 4 g/kg Urea for 5 days. Dogs dosed orally with 5 to 30 g/L Urea for 4 to 10 days had signs of toxicity, including weakness, anorexia, vomiting and retching, diarrhea and a decreased body temperature, which led to a deep torpor or coma. No significant microscopic changes were observed in the skin of male nude mice dermally exposed to 100% Urea for 24 h. No observable effect on fetal development was seen in rats and mice dosed orally with an aqueous solution of Urea (2000 mg/kg) on days 10 and 12 of gestation. The mean number of implants, live fetuses, percent fetal resorptions, mean fetal weight, and percent fetuses malformed were comparable to control group. A detergent containing 15% Urea was injected into pregnant ICR-JCl mice and dams and fetuses had no significant differences when compared to control animals. Urea given orally did not enhance the developmental toxicity of N-nitrosomethylurea. Female Sprague-Dawley rats injected in the uterine horn with 0.05 ml Urea on day 3 (preimplantation) or on day 7 (post implantation) exhibited no maternal mortality or morbidity; a dose-dependent reduction in embryo survival was seen with preimplantation treatment. Urea injected intra-amniotically induces mid-trimester abortions in humans. Urea was not genotoxic in several bacterial and mammalian assays; although in assays where Urea was used at a high concentration, genotoxicity was found, many in in vitro assays. Urea is commonly used in studies of DNA because it causes uncoiling of DNA molecules. Urea was not carcinogenic in Fisher 344 rats or C57B1/6 mice fed diets containing up to 4.5% Urea. Exposure of normal human skin to 60% Urea produced no significant irritation in one study, but 5% Urea was slightly irritating and 20% Urea was irritating in other reports. Burning sensations are the most frequently reported effect of Urea used alone or with other agents in treatment of diseased skin. Overall, there are few reports of sensiti



The shape of urea  

Microsoft Academic Search

The shape of the urea molecule has been studied by analysing the microwave spectra of several isotopic species, yielding rs coordinates of all atoms except that of C, the latter being derived from first-moment equations, and by ab initio molecular-orbital calculations at the MP26-311++G(d,p) level. The derived bond lengths and angles are: r(CO), 1.221 Ĺ; r(CN), 1.378 Ĺ; r(NH(5)), 0.998

Peter D. Godfrey; Ronald D. Brown; Andrew N. Hunter



Drug Binding and Solubility in Milk  

Microsoft Academic Search

The binding and solubility of nitrofurantoin, piroxicam, indomethacin, prednisolone, diazepam, dicumarol, and griseofulvin in milk were determined at 15, 25, and 37°C in bovine milk samples with fat contents of 0.75 and 3.50%. Drug binding to milk components was independent of drug concentration over the drug concentration studied, and the fat content of milk strongly affected binding values of most

Panayotis E. Macheras; Michael A. Koupparis; Sophia G. Antimisiaris



Novel cardiac protective effects of urea: from shark to rat  

PubMed Central

This study was carried out to investigate novel cardioprotective effects of urea and the underlying mechanisms. The cardiac functions under oxidative stress were evaluated using Langendorff perfused isolated heart.Isolated dogfish shark hearts tolerated the oxidative stress generated by electrolysis (10?mA, 1?min) of the perfusion solution (n=4), and also showed normal cardiac functions during post-ischaemia reperfusion (n=4). The high concentration of urea (350?mM) in the heart perfusate was indispensable for maintaining the normal cardiac functions of the shark heart.Urea at 3–300?mM (n=4 for each group) protected the isolated rat heart against both electrolysis-induced heart damage and post-ischaemia reperfusion-induced cardiac injury.A concentration-dependent scavenging effect of urea (3–300?mM, n=4 for each group) against electrolysis-induced reactive oxygen species was also demonstrated in vitro.Urea derivatives as hydroxyurea, dimethylurea, and thiourea had antioxidant cardioprotective effect against the electrolysis-induced cardiac dysfunction of rat heart, but were not as effective as urea in suppressing the post-ischaemia reperfusion injury.Our results suggest that urea and its derivatives are potential antioxidant cardioprotective agents against oxidative stress-induced myocardium damage including the post-ischaemia reperfusion-induced injury.

Wang, Xintao; Wu, Lingyun; Aouffen, M'hamed; Mateescu, Mircea-Alexandru; Nadeau, Reginald; Wang, Rui



Aqueous urea solution destabilizes Abeta(16-22) oligomers.  


We use long multiple trajectories generated by molecular dynamics simulations to probe the stability of oligomers of Abeta(16-22) (KLVFFAE) peptides in aqueous urea solution. High concentration of urea promotes the formation of beta-strand structures in Abeta(16-22) monomers, whereas in water they adopt largely compact random coil structures. The tripeptide system, which forms stable antiparallel beta-sheet structure in water, is destabilized in urea solution. The enhancement of beta-strand content in the monomers and the disruption of oligomeric structure occur largely by direct interaction of urea with the peptide backbone. Our simulations suggest that the oligomer unbinding dynamics is determined by two opposing effects, namely, by the increased propensity of monomers to form beta-strands and the rapid disruption of the oligomers. The qualitative conclusions are affirmed by using two urea models. Because the proposed destabilization mechanism depends largely on hydrogen bond formation between urea and the peptide backbone, we predict that high urea concentration will destabilize oligomers of other amyloidogenic peptides as well. PMID:15465917

Klimov, D K; Straub, John E; Thirumalai, D



Organic Milk Production in Germany  

Microsoft Academic Search

This paper reports the results of a study of organic milk production in Germany, based on a sample of 268 organic dairy farms with 7,990 cows. The average milk yield of these farms was 4,941 kg per cow per lactation. The organic cows on average were only 5.7 years old, and were milked for only 3.2 years. Concentrate feeding was

C. Krutzinna; E. Boehncke; H.-J. Herrmann



Cow's Milk and Goat's Milk.  


Cow's milk is increasingly suggested to play a role in the development of chronic degenerative, non-communicable disorders whereas goat's milk is advocated as having several health benefits. Cow's milk is a rich and cheap source of protein and calcium, and a valuable food for bone health. Despite their high content in saturated fats, consumption of full-fat dairy products does not seem to cause significant changes in cardiovascular disease risk variables. Early introduction of cow's milk is a strong negative determinant of iron status. Unmodified cow's milk does not meet nutritional requirements of infants although it is acceptable to add small volumes of cow's milk to complementary foods. Cow's milk protein allergy has a prevalence ranging from 2 to 7%, and the age of recovery is usually around 2-3 years. The evidence linking cow's milk intake to a later risk of type 1 diabetes or chronic degenerative, non-communicable disorders (obesity, metabolic syndrome, type 2 diabetes, hypertension) is not convincing. Milk probably protects against colorectal cancer, diets high in calcium are a probable cause of prostate cancer, and there is limited evidence suggesting that high consumption of milk and dairy products increases the risk for prostate cancer. There is no evidence to support the use of a cow's milk-free diet as a primary treatment for individuals with autistic spectrum disorders. Unmodified goat's milk is not suitable for infants because of the high protein and minerals content and of a low folate content. Goat's milk has no clear nutritional advantage over cow's milk and is not less allergenic. The European Food Safety Authority recently stated that proteins from goat's milk can be suitable as a protein source for infant and follow-on formula, provided the final product complies with the compositional criteria laid down in Directive 2006/141/EC. PMID:24029787

Turck, Dominique



Mannose-binding lectin 1 haplotypes influence serum MBL-A concentration, complement activity, and milk production traits in Chinese Holstein cattle.  


Mannose-binding lectin (MBL) is a member of the collectin protein family that binds a broad range of microorganisms and activates the lectin-complement pathway of innate immunity. MBL deficiency is associated with an increased risk for various infections and arises from five polymorphisms in the promoter and first exon of the MBL gene in humans. In this study, three novel single-nucleotide polymorphisms (SNPs) in the promoter region and two previously reported SNPs in exon 2 of the MBL1 gene were detected using PCR single-strand conformation polymorphism, restriction fragment length polymorphism, and DNA sequencing in 537 cattle from three Chinese breeds. Analysis of the genotypes and haplotypes was used to investigate the polymorphisms and their possible implications, especially their association with serum MBL-A levels, complement activity (CH50 and ACH50), and milk production traits was investigated. The g.2651G > A SNP in exon 2 affected the serum MBL-A concentrations and the serum CH50 values, whereas the g.-1330G > A SNP significantly affected CH50 and the somatic cell scores (SCSs). Statistical analysis revealed that cows with the ATGGC/ACAAC combined genotype and those with the AAGGT/ACGGT combined genotype exhibited the lowest and highest SCSs, respectively. Serum antibacterial activities were also conducted to verify the effect of the SNPs on resistance to mastitis pathogens. Results of real-time PCR showed that the liver of cows with clinical mastitis exhibited a higher MBL1 expression compared with healthy ones (P ?milk production traits to control mastitis. PMID:21695551

Liu, Jianbo; Ju, Zhihua; Li, Qiuling; Huang, Jinming; Li, Rongling; Li, Jiangbin; Ma, Lijuan; Zhong, Jifeng; Wang, Changfa



Benzobisoxazole fluorophore vicariously senses amines, ureas, anions.  


A benzobisoxazole-based cruciform fluorophore forms fluorescent complexes with simple boronic acids. Through the changes of their fluorescence emission colours, these complexes can sense and qualitatively distinguish among structurally similar organic nitrogen compounds (amines and ureas) and small organic and inorganic anions. Preliminary results suggest that the intensity of this hybrid sensor's fluorescent response to chloride anions can be quantitatively correlated to chloride concentration. PMID:22983092

Lim, Jaebum; Miljani?, Ognjen Š



Effects of Rumen-undegradable Protein and Feed Intake on Purine Derivative and Urea Nitrogen: Comparison with Predictions from the Cornell Net Carbohydrate and Protein System  

Microsoft Academic Search

Si x multiparous Holstein cows were used in a 6 × 6 Latin square to investigate the ability of the Cornell Net Carbohydrate and Protein System to predict ac- curately rumen microbial yield, plasma urea N, and milk urea N. Estimations for microbial protein yield were compared with the measured excretion of purine derivative N in urine. A 3 ×

S. Moscardini; T. C. Wright; P. H. Luimes; B. W. McBride; P. Susmel



Urea biosensors based on PVC membrane containing palmitic acid.  


A new urea biosensor was prepared by immobilizing urease with four different procedures on poly(vinylchloride) (PVC) ammonium membrane electrode containing palmitic acid by using nonactine as an ammonium-ionophore. The analytical characteristics were investigated and were compared those of the biosensor prepared by using carboxylated PVC. The effect of pH, buffer concentration, temperature, urease concentration, stirring rate and enzyme immobilization procedures on the response to urea of the enzyme electrode were investigated. The linear working range and sensitivity of the biosensor were also determined. The urea biosensor prepared by using the PVC membranes containing palmitic acid showed more effective performance than those of the carboxylated PVC based biosensors. Additionally, urea assay in serum was successfully carried out by using the standard addition method. PMID:16152697

Karaku?, Emine; Pekyardimci, Sule; Esma, Kiliç



Evidence for urea-induced hypometabolism in isolated organs of dormant ectotherms.  


Many organisms endure extended periods of dormancy by depressing their metabolism, which effectively prolongs the use of their endogenous energy stores. Though the mechanisms of hypometabolism are varied and incompletely understood, recent work suggests that urea accumulation in autumn and early winter contributes to reduced metabolism of hibernating wood frogs (Rana sylvatica). Urea accumulation during dormancy is a widespread phenomenon, and it has long been presumed that numerous species from diverse taxa benefit from its hypometabolic effect. To investigate the phylogenetic prevalence of urea-induced hypometabolism, we studied four species of urea accumulators from the clades Amphibia (Spea bombifrons and Ambystoma tigrinum), Reptilia (Malaclemys terrapin), and Gastropoda (Anguispira alternata), and one amphibian species (R. pipiens) that does not accumulate urea during dormancy. We measured rates of oxygen consumption (VO(2)) of excised organ samples from dormant animals in the presence or absence of physiological concentrations of urea. Three of the four urea-accumulating species had at least one organ whose VO(2) was significantly decreased by urea treatment. However, VO(2) of organs from R. pipiens, the one species tested that does not accumulate urea during dormancy, was not affected by urea treatment. Our results support the hypothesis that urea accumulation can reduce metabolic rate of dormant animals and provide a base for further investigation into the evolution of urea-induced hypometabolism. PMID:19739087

Muir, Timothy J; Costanzo, Jon P; Lee, Richard E



Cortisol-sensitive urea transport across the gill basolateral membrane of the gulf toadfish (Opsanus beta).  


Gulf toadfish (Opsanus beta) use a unique pulsatile urea excretion mechanism that allows urea to be voided in large pulses via the periodic insertion or activation of a branchial urea transporter. The precise cellular and subcellular location of the facilitated diffusion mechanism(s) remains unclear. An in vitro basolateral membrane vesicle (BLMV) preparation was used to test the hypothesis that urea movement across the gill basolateral membrane occurs through a cortisol-sensitive carrier-mediated mechanism. Toadfish BLMVs demonstrated two components of urea uptake: a linear element at high external urea concentrations, and a phloretin-sensitive saturable constituent (K(m) = 0.24 mmol/l; V(max) = 6.95 micromol x mg protein(-1) x h(-1)) at low urea concentrations (<1 mmol/l). BLMV urea transport in toadfish was unaffected by in vitro treatment with ouabain, N-ethylmaleimide, or the absence of sodium, conditions that are known to inhibit sodium-coupled and proton-coupled urea transport in vertebrates. Transport kinetics were temperature sensitive with a Q(10) > 2, further suggestive of carrier-mediated processes. Our data provide evidence that a basolateral urea facilitated transporter accelerates the movement of urea between the plasma and gills to enable the pulsatile excretion of urea. Furthermore, in vivo infusion of cortisol caused a significant 4.3-fold reduction in BLMV urea transport capacity in lab-crowded fish, suggesting that cortisol inhibits the recruitment of urea transporters to the basolateral membrane, which may ultimately affect the size of the urea pulse event in gulf toadfish. PMID:19458274

Rodela, Tamara M; Gilmour, Kathleen M; Walsh, Patrick J; McDonald, M Danielle



Dicarboxylic Acid-Urea Complexes.  

National Technical Information Service (NTIS)

A study of the reaction of several acids with urea resulted in a series of compounds of varying stoichiometry and structure. The acids having the structure HO2C(CH2)nCO2H produced saltlike compounds with urea when n = 0 and 1 and H-bonded complexes for n ...

J. Radell B. W. Brodman J. J. Domanski



Urea kinetic modeling for CRRT  

Microsoft Academic Search

Urea kinetic modeling (UKM) for dialysis quantification and prescription, although widely used in chronic renal failure (CRF), has been largely absent in the acute setting. A quantitative approach to prescription of continuous renal replacement therapies (CRRTs) for acute renal failure (ARF) based on UKM is presented. For patients with a relatively constant urea generation rate, G, who are receiving a

Laurie Garred; Martine Leblanc; Bernard Canaud



Studies on Antiretroviral Drug Concentrations in Breast Milk: Validation of a Liquid Chromatography-Tandem Mass Spectrometric Method for the Determination of 7 Anti-Human Immunodeficiency Virus Medications  

PubMed Central

Studying the pharmacokinetics of antiretroviral drugs in breast milk has important implications for the health of both the mother and the infant, particularly in resource-poor countries. Breast milk is a highly complex biological matrix, yet it is necessary to develop and validate methods in this matrix, which simultaneously measure multiple analytes, as women may be taking any number of drug combinations to combat human immunodeficiency virus infection. Here, we report a novel extraction method coupled to high-performance liquid chromatography and tandem mass spectrometry for the accurate, precise, and specific measurement of 7 antiretroviral drugs currently prescribed to infected mothers. Using 200 µL of human breast milk, simultaneous quantification of lamivudine (3TC), stavudine (d4T), zidovudine (ZDV), nevirapine (NVP), nelfinavir (NFV), ritonavir, and lopinavir was validated over the range of 10–10,000 ng/mL. Intraday accuracy and precision for all analytes were 99.3% and 5.0 %, respectively. Interday accuracy and precision were 99.4 % and 7.8%, respectively. Cross-assay validation with UV detection was performed using clinical breast milk samples, and the results of the 2 assays were in good agreement (P = 0.0001, r = 0.97). Breast milk to plasma concentration ratios for the different antiretroviral drugs were determined as follows: 3TC = 2.96, d4T = 1.73, ZDV = 1.17, NVP = 0.82, and NFV = 0.21.

Rezk, Naser L.; White, Nicole; Bridges, Arlene S.; Abdel-Megeed, Mohamed F.; Mohamed, Tarek M.; Moselhy, Said S.; Kashuba, Angela D. M.



Fumonisin B1 Increases Serum Sphinganine Concentration but Does Not Alter Serum Sphingosine Concentration or Induce Cardiovascular Changes in Milk-Fed Calves  

Microsoft Academic Search

Fumonisin B1 is the most toxic and commonly occurring form of a group of mycotoxins that alter sphingolipid biosynthesis and induce leukoencephalomalacia in horses and pulmonary edema in pigs. Purified fumonisin B1 (1 mg\\/kg, iv, daily) increased serum sphinganine and sphingosine concentrations and decreased car- diovascular function in pigs within 5 days. We therefore examined whether the same dosage schedule

S. Mathur; Mike E. Tumbleson; Geoffrey W. Smith; William J. Tranquilli; Dawn E. Morin; Wanda M. Haschek



Effect of the Dietary Ratio of Hay to Concentrate on Milk Production, Ration Digestibility, and Urinary Energy Losses  

Microsoft Academic Search

SUMMARY Lactation and balance studies were carried out with 12 Holstein cows in a randolnized complete block design. Twenty, forty, or sixty per cent of the estimated net energy (ENE) was supplied in the form of hay; the remainder in the forln of concentrate. The level of ENE intake above maintenance was held constant. FCM production was approximately the same

J. M. Elliot; J. K. Loosli



Influence of Pasteurization and Cool-Aging on the Behavior of Pure Salt Solutions Prepared in Accordance with the Composition and Concentrations in Milk  

Microsoft Academic Search

SUMMARY A pure salt solution was prepared to sinmlate the composition of salts in milk serum, in order to study the mineral balance in milk. The salts were distributed into soluble and colloidal phases and a sediment was separated from the solution by centri- fugation. Storage resulted in formations that resembled \\

I. S. Verma; H. H. Sommer



The effect of increasing the nutrient and amino acid concentration of milk diets on dairy heifer individual feed intake, growth, development, and lactation performance.  


Increasing early (<3 mo) nutrient feeding levels and growth rate of dairy calves has been found to increase their milk production potential. The objective of this study was to compare the effect of offering milk diets with or without added carbohydrates and amino acids on calf growth, weaning age, and subsequent growth and milk yield of dairy heifers in their first lactation. Friesian calves born at Massey University (n=57) were selected at random, weighed, and allocated to receive 1 of 3 diets. All calves were fed colostrum from 1 to 3d of age, followed by 4L of whole milk (WM) per head per day and probiotics between 3 and 18d of age. At 18d of age, calves were weighed to ensure mean body weight (BW); then, at 19d of age, calves changed diets to 1 of 3 treatments, which reached full treatment rate at 21d of age. The diets were 4L/head per day of WM (M); 4L/head per day of WM plus 200g of plant carbohydrates (MP); and 4L/head per day of WM plus 200g of plant carbohydrates with amino acids (MPA). Calves were weaned upon reaching a BW of 90kg. During this period, BW, body condition, and hip height and width were measured. The heifers were commingled and grazed on ryegrass and white clover pastures until calving at 23 mo of age, when BW, body condition, and hip height and width were measured again. Milk yield and composition were measured throughout first lactation. At weaning, calves fed MPA had greater mean BW gain, a lower number of days to target BW, and a greater mean hip width gain compared with calves in the M group, although mean gain in hip height did not differ among treatments. Total calf starter intake during the milk period was lower for MPA-fed calves compared with those offered M, mainly due to a shorter milk feeding period required to attain the 90-kg weaning weight, whereas mean daily starter intake and straw intake did not differ. No difference was observed in the calving rate or calving age of heifers in any of the dietary feeding groups. First lactation fat-corrected milk yield, milk fat percentage, and total milk fat and protein yields were greater for animals reared on MP and MPA compared with M. Body weight, hip height and width at parturition, milk protein percentage, somatic cell count, or days in milk did not differ among treatments. Increasing nutrient intake, during the milk feeding period, improved the BW gain of calves and milk production of dairy heifers during first lactation. PMID:23958020

Margerison, J K; Robarts, A D J; Reynolds, G W



Variation in milk cortisol during lactation in Murciano-Granadina goats.  


Fifty-seven goats were included in an experiment designed to study the effect of lactation stage, parity number, and mammary gland health status on milk cortisol concentration as a method to assess the welfare of Murciano-Granadina goats. The relationships of milk cortisol concentration with different production parameters (milk yield, milk composition, and mechanical milking ability: milk fractioning during milking and milking time) were also studied. The experiment lasted 8 mo and monthly samplings were carried out to determine total milk yield (MY), fractioning during milking (machine milk, MM; machine stripping milk, MSM), and milking time (MT), and a sample was taken from the total milk yield to determine milk cortisol concentration, somatic cell count, and milk composition (fat, protein, and lactose). To determine the infection status of the gland, an aseptic sample was taken for bacteriological analysis before each monthly sampling. Third-parity goats presented higher concentrations of milk cortisol than those of 1, 2, or ? 4 parities. Intramammary infection had no effect on milk cortisol concentration, and somatic cell count did not correlate with cortisol concentration. Cortisol presented a significant correlation with MY and MM, but showed no significant correlation with MSM, MT, or milk composition parameters. Variations in milk cortisol concentration in goats may be associated with different physiological factors in the animal (e.g., milk production level, lactation stage, and parity number) and therefore need not always indicate stress for the animal. PMID:23245963

Díaz, J R; Alejandro, M; Romero, G; Moya, F; Peris, C



Viscoelastic Properties of Coagulating Milk  

Microsoft Academic Search

The viscoelastic properties of co- agulating renneted milk were studied by a dynamic testing technique. With this technique we obtained the dynamic viscosity and elasticity of the milk gel without affecting the coagulation process. We give results in absolute units for the coagulation process as a function of coagulation temperature, rennet con- centration, and concentration of calcium chloride. The shear

Leif Bohlin; Per-Olof Hegg; Helena Ljusberg-Wahren



Effect of Dietary Concentration of Total Nonstructural Carbohydrate on Energy and Nitrogen Metabolism and Milk Production of Dairy Cows1  

Microsoft Academic Search

Two complete blended diets with a ratio of concentrate:silage dry matter of 60:40 were fed to 12 Holstein cows in the first 12 wk of lactation in an in- complete changeover arrangement of treatments. Diets differed (dry basis) in content of total nonstructural carbo- hydrate (24.9% versus 32.9%), neutral detergent fiber (37.0% versus 32.1%), and hemicellulose (19.6% versus 15.7%)but were

C. A. MacGregor; M. R. Stokes; W. H. Hoover; H. A. Leonard; L. L. Junkins Jr.; C. J. Sniffen; R. W. Mailman



Feedback control of milk secretion from milk  

Microsoft Academic Search

Extracellular storage allows biologically-active substances in milk to influence mammary function. Among these factors is one which regulates the rate of milk secretion acutely according to frequency or completeness of milk removal in each mammary gland. The active factor in goat's milk has been identified by screening milk constituents for their ability to inhibit milk constituent secretion in tissue and

Malcolm Peaker; Colin J. Wilde



Effect of dry- versus wet-autoclaving of spray-dried egg albumen compared with casein as protein sources on apparent nitrogen and energy balance, plasma urea nitrogen and glucose concentrations, and growth performance of neonatal swine.  


Forty crossbred neonatal pigs with an average initial age of 4 d and BW of 2.16 kg were used in a 28-d experiment to evaluate the nutritional effects of autoclaving a commercial sugar-free, spray-dried egg albumen (EA) compared with casein. Basal diet protein sources were lactic acid casein and EA. Two more dietary treatments were made by replacing the EA with dry-autoclaved EA (DAEA) or wet-autoclaved EA (WAEA, EA and water mixed in a 1.0:1.2 ratio before autoclaving). The DAEA and WAEA were autoclaved at 121 degrees C and 1.75 kg/cm(2) pressure for 30 min, and WAEA was oven-dried after autoclaving. Analyzed trypsin inhibitor units/mg of EA, DAEA, and WAEA were 535.0, 9.0, and 6.5, respectively. Pigs were fed the diets in gruel form to appetite in individual metabolism cages every 2 h during the experiment. Blood samples were taken on d 7, 14, and 21, and total urine and fecal grab-samples were collected from d 14 to 21 of the experiment. Response criteria were N and energy balance, plasma urea N (PUN) and glucose concentrations, and growth performance. The WAEA was a higher quality protein source for neonatal pigs than DAEA. Pigs fed the diet containing WAEA absorbed and retained more (P < 0.05) grams of N/d, had higher (P < 0.05) percentages of N and energy that were absorbed and retained/intake, had lower (P < 0.05) concentrations of PUN overall, and had higher (P < 0.05) ADG and G:F than pigs fed the diet containing DAEA. Most response criteria of pigs fed the diets containing DAEA or EA were not different, although pigs fed the diet containing DAEA had lower (P < 0.05) overall PUN concentrations, and pigs fed the diet containing EA had higher (P < 0.05) percentages of energy absorbed and retained/intake, and higher ADG and G:F than pigs fed the diet containing DAEA. Growth performance was not different for pigs fed the diets containing WAEA or casein. However, pigs fed the diet containing casein excreted less (P < 0.05) fecal N, retained more (P < 0/05) grams of N/d, had higher percentages of N absorbed and retained/intake, and had lower (P < 0.05) PUN concentrations overall than pigs fed the diet containing WAEA. In conclusion, WAEA was a higher quality protein source for neonatal pigs than DAEA or EA, whereas lactic casein was a higher quality protein source for neonatal pigs than EA, DAEA, or WAEA. PMID:20418450

Watkins, K L; Veum, T L



Increasing the revenues from automatic milking by using individual variation in milking characteristics.  


The objective of this study was to quantify individual variation in daily milk yield and milking duration in response to the length of the milking interval and to assess the economic potential of using this individual variation to optimize the use of an automated milking system. Random coefficient models were used to describe the individual effects of milking interval on daily milk yield and milking duration. The random coefficient models were fitted on a data set consisting of 4,915 records of normal uninterrupted milkings collected from 311 cows kept in 5 separate herds for 1 wk. The estimated random parameters showed considerable variation between individuals within herds in milk yield and milking duration in response to milking interval. In the actual situation, the herd consisted of 60 cows and the automatic milking system operated at an occupation rate (OR) of 64%. When maximizing daily milk revenues per automated milking system by optimizing individual milking intervals, the average milking interval was reduced from 0.421 d to 0.400 d, the daily milk yield at the herd level was increased from 1,883 to 1,909 kg/d, and milk revenues increased from euro498 to euro507/d. If an OR of 85% could be reached with the same herd size, the optimal milking interval would decrease to 0.238 d, milk yield would increase to 1,997 kg/d, and milk revenues would increase to euro529/d. Consequently, more labor would be required for fetching the cows, and milking duration would increase. Alternatively, an OR of 85% could be achieved by increasing the herd size from 60 to 80 cows without decreasing the milking interval. Milk yield would then increase to 2,535 kg/d and milk revenues would increase to euro673/d. For practical implementation on farms, a dynamic approach is recommended, by which the parameter estimates regarding the effect of interval length on milk yield and the effect of milk yield on milking duration are updated regularly and also the milk production response to concentrate intake is taken into account. PMID:20172214

André, G; Berentsen, P B M; Engel, B; de Koning, C J A M; Oude Lansink, A G J M



Highly sensitive urea sensing with ion-irradiated polymer foils  

NASA Astrophysics Data System (ADS)

Recently we prepared urea-sensors by attaching urease to the inner walls of etched ion tracks within thin polymer foil. Here, alternative track-based sensor configurations are examined where the enzyme remained in solution. The conductivities of systems consisting of two parallel irradiated polymer foils and confining different urea/urease mixtures in between were examined. The correlations between conductivity and urea concentration differed strongly for foils with unetched and etched tracks, which points at different sensing mechanisms - tentatively attributed to the adsorption of enzymatic reaction products on the latent track entrances and to the enhanced conductivity of reaction product-filled etched tracks, respectively. All examined systems enable in principle, urea sensing. They point at the possibility of sensor cascade construction for more sensitive or selective sensor systems.

Fink, Dietmar; Muńoz Hernandez, Gerardo; Alfonta, Lital



An investigation of FT-Raman spectroscopy for quantification of additives to milk  

NASA Astrophysics Data System (ADS)

In this research, four chemicals, urea, ammonium sulfate, dicyandiamide, and melamine, were mixed into liquid nonfat milk at concentrations starting from 0.1% to a maximum concentration determined for each chemical according to its maximum solubility, and two Raman spectrometers-a commercial Nicolet Raman system and an in-house Raman Chemical Imaging (RCI) system-were used to acquire Raman shift spectra for these mixture samples. These chemicals are potential adulterants that could be used to artificially elevate protein measurements of milk products evaluated by the Kjeldahl method. Baseline subtraction was employed to eliminate milk intensity, and the normalized Raman intensity was calculated from the specific Raman shift from the spectrum of solid chemical. Linear relationships were found to exist between the normalized Raman intensity and chemical concentrations. The linear regression coefficients (R2) ranged from 0.9111 to 0.998. Although slightly higher R2 values were calculated for regressions using spectral intensities measured by the Nicolet system compared to those using measurements from the RCI system, the results from the two systems were similar and comparable. A very low concentration of melamine (400 ppm) in milk was also found to be detectable by both systems. Raman sensitivity of Nicolet Raman system was estimated from normalized Raman intensity and slope of regression line in this study. Chemicals (0.2%) were dissolved in milk and detected the normalized Raman intensity. Melamine was found to have the highest Raman sensitivity, with the highest values for normalized Raman intensity (0.09) and regression line slope (57.04).

Cheng, Yuche; Qin, Jianwei; Lim, Jongguk; Chan, Diane E.; Kim, Moon S.; Chao, Kuanglin




Technology Transfer Automated Retrieval System (TEKTRAN)

The destruction of urea, its fate and influence on levels of active chlorine as well as formation of byproducts during electrolytic treatment of urea solutions was studied. Treated solutions designed to simulate typical concentrations in dairy manure lagoon water, contained initial concentrations of...


Designer milk.  


Dairy biotechnology is fast gaining ground in the area of altering milk composition for processing and/or animal and human health by employing nutritional and genetic approaches. Modification of the primary structure of casein, alteration in the lipid profile, increased protein recovery, milk containing nutraceuticals, and replacement for infant formula offer several advantages in the area of processing. Less fat in milk, altered fatty acid profiles to include more healthy fatty acids such as CLA and omega-fats, improved amino acid profiles, more protein, less lactose, and absence of beta-lactoglobulin (beta-LG) are some opportunities of "designing" milk for human health benefits. Transgenic technology has also produced farm animals that secrete in their milk, human lactoferrin, lysozyme, and lipase so as to simulate human milk in terms of quality and quantity of these elements that are protective to infants. Cow milk allergenicity in children could be reduced by eliminating the beta-LG gene from bovines. Animals that produce milk containing therapeutic agents such as insulin, plasma proteins, drugs, and vaccines for human health have been genetically engineered. In order to cater to animal health, transgenic animals that express in their mammary glands, various components that work against mastitis have been generated. The ultimate acceptability of the "designer" products will depend on ethical issues such as animal welfare and safety, besides better health benefits and increased profitability of products manufactured by the novel techniques. PMID:17900499

Sabikhi, Latha



Urea treated maize straw for small-scale dairy systems in the highlands of Central Mexico.  


Maize straw is the main roughage for dairy herds in campesino farms in central Mexico. The objective was to evaluate feeding milking cows on maize straw treated with 40 g/kg DM of urea (A) or untreated straw (B), and 3.0 kg/d of 18% CP concentrate. Twenty-four Holsteins in late lactation from 8 farmers were sorted in two groups: sequence A-B-A or B-A-B; periods were 28 days. Mean daily milk yield for the last two weeks per period, and live-weight and body-condition score every 14 days were used for analysis. Maize straw was ad libitum. Chemical analysis and in vitro digestibility were analysed by Student's t test, animal variables by a switch-back design. 'A' had 44.3 g/kg DM more CP and 106.5 g/kg DM higher in vitro digestibility than 'B' (710 g/kg DM +/- 0.75 'A' vs. 603.5 g/kg DM +/- 1.44 'B'). Despite higher digestibility and intake, there were no differences (P > 0.05) for milk yield, live-weight or body-condition score, although there were in straw intake (P < 0.05). Cows on 'A' ate 1.7 kg/cow/day more straw DM than on 'B'. Lack of response did not offset higher feeding costs although margins were high. Lack of response is attributed to short length of periods and late lactation of cows. PMID:19330533

García-Martínez, Anastacio; Albarrán-Portillo, Benito; Castelán-Ortega, Octavio Alonso; Espinoza-Ortega, Angélica; Arriaga-Jordán, Carlos Manuel



PCDD/F reduction in incinerator flue gas by adding urea to RDF feedstock.  


The effect of urea on PCDD/F formation in a pilot incinerator was studied by incinerating urea with refuse-derived fuel (RDF) at three concentrations (0.1%, 0.5% and 1.0%, of the fuel feed). A distinct reduction in both PCDD/F and chlorophenol concentrations could be noticed when urea was introduced into the system. Partial-least-square (PLS) analysis of the data showed the importance of certain chlorophenol isomers as PCDD/F precursors, pointing to the possibility that the impact point of the urea inhibitor could be before the precursor molecules, i.e. chlorophenols, have been formed. PMID:11297399

Ruokojärvi, P; Tuppurainen, K; Mueller, C; Kilpinen, P; Ruuskanen, J



Protein stabilization by urea and guanidine hydrochloride.  


The urea, guanidine hydrochloride, salt, and temperature dependence of the rate of dissociation of CO from a nonequilibrium state of CO-bound native ferrocytochrome c has been studied at pH 7. The heme iron of ferrocytochrome c in the presence of denaturing concentrations of guanidine hydrochloride (GdnHCl) and urea prepared in 0.1 M phosphate, pH 7, binds CO. When the unfolded protein solution is diluted 101-fold into CO-free folding buffer, the protein chain refolds completely, leaving the CO molecule bonded to the heme iron. Subsequently, slow thermal dissociation of the CO molecule yields to the heme coordination of the native M80 ligand. Thus, the reaction monitors the rate of thermal conversion of the CO-liganded native ferrocytochrome c to the M80-liganded native protein. The rate of this reaction, k(diss), shows a characteristic dependence on the presence of nondenaturing concentrations of the denaturants in the reaction medium. The rate decreases by approximately 1.9-3-fold as the concentration of GdnHCl in the refolding medium increases from nearly 0 to approximately 2.1 M. Similarly, the rate decreases by 1.8-fold as the urea concentration is raised from 0.l to approximately 5 M. At still higher concentrations of the denaturants the denaturing effect sets in, the protein is destabilized, and hence the CO dissociation rate increases sharply. The activation energy of the reaction, E(a), increases when the denaturant concentration in the reaction medium is raised: from 24.1 to 28.3 kcal mol(-1) for a 0.05-2.1 M rise in GdnHCl and from 25.2 to 26.9 kcal mol(-1) for a 0.1-26.9 M increase in urea. Corresponding to these increases in denaturant concentrations are also increases in the activation entropy, S(diss)/R, where R is the gas constant of the reaction. The denaturant dependence of these kinetic and thermodynamic parameters of the CO dissociation reaction suggests that binding interactions with GdnHCl and urea can increase the structural and energetic stability of ferrocytochrome c up to the limit of the subdenaturing concentrations of the additives. NaCl and Na(2)SO(4), which stabilize proteins through their salting-in effect, also decrease the rate with a corresponding increase in activation entropy of CO dissociation from CO-bound native ferrocytochrome c, lending support to the view that low concentrations of GdnHCl and urea stabilize proteins. These results have direct relevance to the understanding and interpretation of the free energy-denaturant relationship and protein folding chevrons. PMID:12416983

Bhuyan, Abani K



Yield and aging of Cheddar cheeses manufactured from milks with different milk serum protein contents.  


Whey proteins in general and specifically beta-lactoglobulin, alpha-lactalbumin, and immunoglobulins have been thought to decrease proteolysis in cheeses manufactured from concentrated retentates from ultrafiltration. The proteins found in whey are called whey proteins and are called milk serum proteins (SP) when they are in milk. The experiment included 3 treatments; low milk SP (0.18%), control (0.52%), and high milk SP (0.63%), and was replicated 3 times. The standardized milk for cheese making of the low milk SP treatment contained more casein as a percentage of true protein and more calcium as a percentage of crude protein, whereas the nonprotein nitrogen and total calcium content was not different from the control and high SP treatments. The nonprotein nitrogen and total calcium content of the milks did not differ because of the process used to remove the milk SP from skim milk. The low milk SP milk contained less free fatty acids (FFA) than the control and high milk SP treatment; however, no differences in FFA content of the cheeses was detected. Approximately 40 to 45% of the FFA found in the milk before cheese making was lost into the whey during cheese making. Decreasing the milk SP content of milk by 65% and increasing the content by 21% did not significantly influence general Cheddar cheese composition. Higher fat recovery and cheese yield were detected in the low milk SP treatment cheeses. There was more proteolysis in the low milk SP cheese and this may be due to the lower concentration of undenatured beta-lactoglobulin, alpha-lactalbumin, and other high molecular weight SP retained in the cheeses made from milk with low milk SP content. PMID:16291609

Nelson, B K; Barbano, D M



Structure and dynamics of urea/water mixtures investigated by vibrational spectroscopy and molecular dynamics simulation.  


Urea/water is an archetypical "biological" mixture and is especially well-known for its relevance to protein thermodynamics as urea acts as a protein denaturant at high concentration. This behavior has given rise to an extended debate concerning urea's influence on water structure. On the basis of a variety of methods and of definitions of the water structure, urea has been variously described as a structure-breaker, a structure-maker, or as remarkably neutral toward water. Because of its sensitivity to microscopic structure and dynamics, vibrational spectroscopy can help resolve these debates. We report experimental and theoretical spectroscopic results for the OD stretch of HOD/H2O/urea mixtures (linear IR, 2DIR, and pump-probe anisotropy decay) and for the CO stretch of urea-D4/D2O mixtures (linear IR only). Theoretical results are obtained using existing approaches for water and a modification of a frequency map developed for acetamide. All absorption spectra are remarkably insensitive to urea concentration, consistent with the idea that urea only very weakly perturbs the water structure. Both this work and experiments by Rezus and Bakker, however, show that water's rotational dynamics are slowed down by urea. Analysis of the simulations casts doubt on the suggestion that urea immobilizes particular doubly hydrogen bonded water molecules. PMID:23841646

Carr, J K; Buchanan, L E; Schmidt, J R; Zanni, M T; Skinner, J L



A rapid, two-hour method for the enumeration of total viable bacteria in samples from commercial milk powder and whey protein concentrate powder manufacturing plants  

Microsoft Academic Search

A new protocol specifically designed to enumerate total viable bacteria in milk powder using flow cytometry was validated against aerobic plate counts using 178 samples of whole milk powder. Viable counts, as measured using flow cytometry, correlated well (r2>0.80) with plate counts across the range of powders with counts of 102–108cfug?1. The protocol was then used to enumerate total viable

Steve Flint; Jean-Louis Drocourt; Kylie Walker; Barbara Stevenson; Michelle Dwyer; Ian Clarke; Desmond McGill



Evaporation of urea at atmospheric pressure.  


Aqueous urea solution is widely used as reducing agent in the selective catalytic reduction of NO(x) (SCR). Because reports of urea vapor at atmospheric pressure are rare, gaseous urea is usually neglected in computational models used for designing SCR systems. In this study, urea evaporation was investigated under flow reactor conditions, and a Fourier transform infrared (FTIR) spectrum of gaseous urea was recorded at atmospheric pressure for the first time. The spectrum was compared to literature data under vacuum conditions and with theoretical spectra of monomolecular and dimeric urea in the gas phase calculated with the density functional theory (DFT) method. Comparison of the spectra indicates that urea vapor is in the monomolecular form at atmospheric pressure. The measured vapor pressure of urea agrees with the thermodynamic data obtained under vacuum reported in the literature. Our results indicate that considering gaseous urea will improve the computational modeling of urea SCR systems. PMID:21381736

Bernhard, Andreas M; Czekaj, Izabela; Elsener, Martin; Wokaun, Alexander; Kröcher, Oliver



Causes, kinetics and clinical implications of post-hemodialysis urea rebound  

Microsoft Academic Search

Causes, kinetics and clinical implications of post-hemodialysis urea rebound. The rapid increase in end-dialysis urea concentration (Co) immediately after the end of dialysis (HD), which greatly exceeds that expected as an effect of urea generation and defined as “net rebound,” was assessed in 21 chronic HD patients. The curve of serial values of net rebound correlated (r = 0.70) with

Luciano A Pedrini; Samir Zereik; Samir Rasmy



Urea and protein metabolism in burned children: Effect of dietary protein intake  

Microsoft Academic Search

The response of urea metabolic kinetics, the rate of whole-body protein breakdown, and muscle and skin protein synthesis rates to dietary protein intake (1.15 to 2.92 g\\/kg\\/d) was assessed in children with 20% to 40% total body surface area burn injury using a primed continuous infusion of 15N2-urea and l-13C6-phenylalanine. Plasma urea concentration, production, and excretion rates increased with dietary

Bruce W. Patterson; Thuan Nguyen; Edgar Pierre; David N. Herndon; Robert R. Wolfe



Role of Co-Solute in Biomolecular Stability: Glucose, Urea and the Water Structure  

Microsoft Academic Search

We have studied the action of urea and glucose on the stability of DNAand micelles. We measured the melting temperature of aqueous solutionsof DNA with urea or glucose as a co-solute; we have also measured thechanges in the critical micelle concentrations (cmc) of Sodium DodecylSulfate and Triton X-100 by addition of urea and glucose. Ourexperimental results show that glucose increases

Juan R. de Xammar Oro



Urea transport in the proximal tubule and the descending limb of Henle  

PubMed Central

Urea transport in proximal convoluted tubule (PCT) and descending limb of Henle (DLH) was studied in perfused segments of rabbit nephrons in vitro. Active transport of urea was ruled out in a series of experiments in which net transport of fluid was zero. Under these conditions the collected urea concentration neither increased nor decreased when compared to the mean urea concentration in the perfusion fluid and the bath. Permeability coefficient for urea (Purea) was calculated from the disappearance of urea-14C added to perfusion fluid. Measurements were obtained under conditions of zero net fluid movement: DLH was perfused with isosmolal ultrafiltrate (UF) of the same rabbit serum as the bath, while PCT was perfused with equilibrium solution (UF diluted with raffinose solution for fluid [Na] = 127 mEq/liter). Under these conditions Purea per unit length was 3.3±0.4 × 10-7 cm2/sec (5.3±0.6 × 10-5 cm/sec assuming I.D. = 20?) in PCT and 0.93±0.4 × 10-7 cm2/sec (1.5±0.5 × 10-5 cm/sec) in DLH. When compared to previously published results, these values show that the PCT is 2.5 times less permeable to urea than to Na, while the DLH is as impermeable to urea as to Na. These results further indicate that the DLH is less permeable to both Na and urea than the PCT. The reflection coefficient for urea, ?urea, was calculated as the ratio of induced solution efflux when 95 mOsm/liter of urea was added to the bath, as compared to net fluid movement induced by addition to the bath of equivalent amount of raffinose, ?urea in DLH is 0.95±0.4 as compared to 0.91±0.05 in PCT. ?urea in DLH is approximately equal to ?Na; however, ?urea in PCT is higher than ?Na (0.68). Several types of studies were conducted to examine the role of urea and urea plus sodium chloride in concentrating the fluid in the DLH. From the obtained results it was concluded that the intraluminal fluid of DLH is primarily concentrated by abstraction of water without significant net entry of solute. These results are discussed with respect to possible significance in the overall operation of the countercurrent system.

Kokko, Juha P.



Amitriptyline and nortriptyline excretion in human breast milk  

Microsoft Academic Search

Simultaneous blood and milk samples were obtained from a 30-year-old woman who was on sustained release amitriptyline, and the concentrations of amitriptyline and the active metabolite, nortriptyline, were estimated by GLC. Serum and milk concentrations were similar with a slight tendency for the amitriptyline concentrations to be higher in milk. Calculation of the transfer of drug from the mother to

L. Brixen-Rasmussen; J. Halgrener; A. Jřrgensen



NiO nanoparticle-based urea biosensor.  


NiO nanoparticles (NiO-NPs) have been exploited successfully for the fabrication of a urea biosensor. A thin film of NiO nanoparticles deposited on an indium tin oxide (ITO) coated glass substrate serves as an efficient matrix for the immobilisation of urease (Ur), the specific enzyme for urea detection. The prepared bioelectrode (Ur/NiO-NP/ITO/glass) is utilised for urea sensing using cyclic voltammetry and UV-visible spectroscopy. NiO nanoparticles act as electro-catalytic species that are based on the shuttling of electrons between Ni(2+) and Ni(3+) in the octahedral site and result in an enhanced electrochemical current response. The prepared bioelectrode (Ur/NiO-NPs/ITO/glass) exhibits a high sensitivity of 21.3 ?A/(mM (*) cm(2)) and a good linearity in a wide range (0.83-16.65 Mm) of urea concentrations with fast response time of 5s. The low value of the Michaelis-Menten constant (K(m)=0.34 mM) indicates the high affinity of Ur towards the analyte (urea). The high catalytic activity, along with the redox behaviour of NiO-NPs, makes it an efficient matrix for the realisation of a urea biosensor. PMID:22947517

Tyagi, Manisha; Tomar, Monika; Gupta, Vinay



Effect of forage conservation method on plasma lipids, mammary lipogenesis, and milk fatty acid composition in lactating cows fed diets containing a 60:40 forage-to-concentrate ratio.  


The effects of forage conservation method on plasma lipids, mammary lipogenesis, and milk fat were examined in 2 complementary experiments. Treatments comprised fresh grass, hay, or untreated (UTS) or formic acid treated silage (FAS) prepared from the same grass sward. Preparation of conserved forages coincided with the collection of samples from cows fed fresh grass. In the first experiment, 5 multiparous Finnish Ayrshire cows (229 d in milk) were used to compare a diet based on fresh grass followed by hay during 2 consecutive 14-d periods, separated by a 5-d transition during which extensively wilted grass was fed. In the second experiment, 5 multiparous Finnish Ayrshire cows (53 d in milk) were assigned to 1 of 2 blocks and allocated treatments according to a replicated 3×3 Latin square design, with 14-d periods to compare hay, UTS, and FAS. Cows received 7 or 9 kg/d of the same concentrate in experiments 1 and 2, respectively. Arterial concentrations of triacylglycerol (TAG) and phospholipid were higher in cows fed fresh grass, UTS, and FAS compared with hay. Nonesterified fatty acid (NEFA) concentrations and the relative abundance of 18:2n-6 and 18:3n-3 in TAG of arterial blood were also higher in cows fed fresh grass than conserved forages. On all diets, TAG was the principle source of fatty acids (FA) for milk fat synthesis, whereas mammary extraction of NEFA was negligible, except during zero-grazing, which was associated with a lower, albeit positive calculated energy balance. Mammary FA uptake was higher and the synthesis of 16:0 lower in cows fed fresh grass than hay. Conservation of grass by drying or ensiling had no influence on mammary extraction of TAG and NEFA, despite an increase in milk fat secretion for silages compared with hay and for FAS than UTS. Relative to hay, milk fat from fresh grass contained lower 12:0, 14:0, and 16:0 and higher S3,R7,R11,15-tetramethyl-16:0, cis-9 18:1, trans-11 18:1, cis-9,trans-11 18:2, 18:2n-6, and 18:3n-3 concentrations. Even though conserved forages altered mammary lipogenesis, differences in milk FA composition were relatively minor, other than a higher enrichment of S3,R7,R11,15-tetramethyl-16:0 in milk from silages compared with hay. In conclusion, differences in milk fat composition on fresh grass relative to conserved forages were associated with a lower energy balance, increased uptake of preformed FA, and decreased synthesis of 16:0 de novo in the mammary glands, in the absence of alterations in stearoyl-coenzyme A desaturase activity. PMID:23769378

Halmemies-Beauchet-Filleau, A; Kairenius, P; Ahvenjärvi, S; Toivonen, V; Huhtanen, P; Vanhatalo, A; Givens, D I; Shingfield, K J



Feed-back control of milk secretion in the goat by a chemical in milk.  


In order to investigate the nature of the inhibition of milk secretion during a long milking interval, goats were treated in three possible ways: (i) milked twice daily at 08.00 h and 16.00 h or (ii) milked thrice daily at 00.00 h, 08.00 h and 16.00 h, or (iii) milked thrice daily at 00.00 h, 08.00 h and 16.00 h, but at 00.00 h the milk removed was replaced with an equal volume of isosmotic sucrose solution. The latter treatment was carried out in order to subject the gland to a degree of physical distension equivalent to that on treatment (i). On either thrice-daily milking or thrice-daily milking with sucrose replacement, milk secretion rate over the 16.00-08.00 h period was significantly higher (by about 10% in both cases) than on twice-daily milking. Secretion rates of lactose, milk protein, citrate and calcium during the 00.00-08.00 h period were similar on either thrice-daily milking or thrice-daily milking with sucrose replacement; the secretion rate of fat was significantly higher on thrice-daily milking with sucrose replacement. Secretion rates of Na+, K+ and Cl- were significantly higher on thrice-daily milking with sucrose replacement. In the case of Na+, the increased Na+ secretion rate was sufficient to create a normal Na+ concentration in the milk/sucrose mixture removed at the next milking. In the cases of K+ and Cl-, their secretion rates were not sufficient to restore their concentrations to normal by the next milking.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6540305

Henderson, A J; Peaker, M



Effects of heating temperatures and addition of reconstituted milk on the heat indicators in milk.  


The objective of the present study was to evaluate the effect of heating temperatures and reconstituted milk on heat treatment indicators in milk by comparing the heat damage between raw milk and raw milk plus reconstituted milk (composite milk). The contents of lactulose, furosine, beta-lactoglobulin, and lactoperoxidase were determined after the heat indicators were heated to 65 to 115 °C for 15 s both in raw milk and composite milk. In the raw milk, the lactulose and furosine contents increased with increased heating temperature, while the beta-lactoglobulin content and lactoperoxidase activity decreased. The lactulose and furosine contents were increased after the addition of reconstituted milk. The reconstituted milk also significantly (P < 0.05) reduced the concentration of beta-lactoglobulin in the milk. Both heat treatment and an addition of reconstituted milk decreased the lactoperoxidase activity significantly (P < 0.05), and the lactoperoxidase activity was undetectable at 85 °C. The ratios of lactulose to furosine in pasteurized milk were higher than that in composite pasteurized milk. It is concluded that lactulose, furosine, and beta-lactoglobulin are suitable indicators of high heat pasteurization or raw milk, while lactoperoxidase may be used in monitoring mild heat pasteurization. Practical Application: Adequate heat treatment is necessary to destroy the microbes in raw milk. However, excessive heat treatment can result in inactivation of active compounds or loss of nutrients. The present study showed that the concentrations of lactulose, furosine, beta-lactoglobulin, and the activity of lactoperoxidase are sensitive to processing temperature and can serve as indicators of milk pasteurization. PMID:21535481

Lan, X Y; Wang, J Q; Bu, D P; Shen, J S; Zheng, N; Sun, P



Effects of increasing the milk yield of dairy cows on milk composition  

Microsoft Academic Search

A meta-analysis of published and unpublished data (998 treatment means) comprising of milk production trials in dairy cows fed mainly grass silage-based diets was conducted to examine the effects of increasing milk yield on milk composition. The data was divided into seven subsets investigating the effects of level of concentrate, protein and fat supplementation, carbohydrate composition of the supplement, silage

P. Huhtanen; M. Rinne


Milk Thistle  


... type 2 diabetes and cirrhosis, and reducing the growth of breast, cervical, and prostate cancer cells. Silymarin, which can be extracted from the seeds (fruit) of the milk thistle plant, is believed to be the biologically active part ...


Disappearing Milk  

NSDL National Science Digital Library

A magician pours milk into a glass, but when he turns the glass upside down, nothing comes out. How does he do it? Discover the science behind the magic in this video adapted from the American Society of Mechanical Engineers.

Foundation, Wgbh E.



Got milk?  

NASA Astrophysics Data System (ADS)

While celebrities wear white “milk moustaches” in a popular U.S. advertising campaign to promote the drinking of milk, they should also be concerned about the decreased amount of calcium available to many trees.Calcium levels in forest soils have decreased at locations in 10 states in the eastern United States, according to a new report by the U.S. Geological Survey (USGS) released in time for National Arbor Day on April 30.

Showstack, Randy


Got milk?  

Microsoft Academic Search

While celebrities wear white ``milk moustaches'' in a popular U.S. advertising campaign to promote the drinking of milk, they should also be concerned about the decreased amount of calcium available to many trees.Calcium levels in forest soils have decreased at locations in 10 states in the eastern United States, according to a new report by the U.S. Geological Survey (USGS)

Randy Showstack



Analysis of the stability of urea in dried blood spots collected and stored on filter paper.  


The ability to use dry blood spots (DBSs) on filter paper for the analysis of urea levels could be an important diagnostic tool for areas that have limited access to laboratory facilities. We developed a method for the extraction and quantification of urea from DBSs that were stored on 3M Whatman filter paper and investigated the effect of long-term storage on the level of urea in DBSs. DBSs of 4.5 mm in diameter were used for our assay, and we determined the urea levels in blood using a commercially available enzymatic kit (UV GLDH-method; Randox laboratories Ltd., UK). The DBSs on filter discs were stored at 4? or at 37? for 120 days. The mean intra- and inter-assay coefficient of variance for our method of urea extraction from dried blood was 4.2% and 6.3%, respectively. We collected 75 fresh blood samples and compared the urea content of each fresh sample with the urea content of DBSs taken from corresponding fresh blood samples. Regression analysis reported a regression coefficient (r) value of 0.97 and a recovery of urea from dried spots was 102.2%. Urea concentrations in DBSs were stable for up to 120 and 90 days when stored at 4? and 37?, respectively. Our results show that urea can be stored and quantitatively recovered from small volumes of blood that was collected on filter paper. PMID:23667845

Quraishi, Rizwana; Lakshmy, Ramakrishnan; Mukhopadhyay, Ashok Kumar; Jailkhani, Bansi Lal



Analysis of the Stability of Urea in Dried Blood Spots Collected and Stored on Filter Paper  

PubMed Central

The ability to use dry blood spots (DBSs) on filter paper for the analysis of urea levels could be an important diagnostic tool for areas that have limited access to laboratory facilities. We developed a method for the extraction and quantification of urea from DBSs that were stored on 3M Whatman filter paper and investigated the effect of long-term storage on the level of urea in DBSs. DBSs of 4.5 mm in diameter were used for our assay, and we determined the urea levels in blood using a commercially available enzymatic kit (UV GLDH-method; Randox laboratories Ltd., UK). The DBSs on filter discs were stored at 4? or at 37? for 120 days. The mean intra- and inter-assay coefficient of variance for our method of urea extraction from dried blood was 4.2% and 6.3%, respectively. We collected 75 fresh blood samples and compared the urea content of each fresh sample with the urea content of DBSs taken from corresponding fresh blood samples. Regression analysis reported a regression coefficient (r) value of 0.97 and a recovery of urea from dried spots was 102.2%. Urea concentrations in DBSs were stable for up to 120 and 90 days when stored at 4? and 37?, respectively. Our results show that urea can be stored and quantitatively recovered from small volumes of blood that was collected on filter paper.

Lakshmy, Ramakrishnan; Mukhopadhyay, Ashok Kumar; Jailkhani, Bansi Lal