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1

Variability of urea concentration in camel milk in Kazakhstan  

E-print Network

Note Variability of urea concentration in camel milk in Kazakhstan Bernard FAYE 1*, Gaukhar-protein nitrogen in milk. The variability of its concentration was never reported in camel milk. The present communication aimed to give some reference values on urea content in camel milk and to explore some

Paris-Sud XI, Université de

2

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

PubMed

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

2013-11-01

3

Milk urea concentration as affected by complete diet feeding and protein balance in the rumen of dairy cattle  

Microsoft Academic Search

The effect of feeding a total mixed ration (TMR) and the effect of protein balance in the rumen (OEB) on milk urea concentration (MUC) was studied. Eighteen Holstein cows were offered three diets in a 3×3 Latin square design. Separate feeding (rations 1 and 3) of maize silage in the morning and prewilted grass silage in the evening was compared

N. E. Geerts; D. L. De Brabander; J. M. Vanacker; J. L. De Boever; S. M. Botterman

2004-01-01

4

Milk Urea Nitrogen Target Concentrations for Lactating Dairy Cows Fed According to National Research Council Recommendations1  

Microsoft Academic Search

The objectives of this study were to develop and evaluate a mathematical model to predict milk urea N and to use this model to establish target concentra- tions. A mechanistic model to predict milk urea N was developed using raw data from 3 studies (10 diets, 40 cows, and 70 observations) and was evaluated with 18 independent studies (89 treatment

J. S. Jonker; R. A. Kohn; R. A. Erdman

1999-01-01

5

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

2010-01-01

6

Supplementation of Urea Level and Malate in Concentrate Containing High Cassava Chip on Rumen Ecology and Milk Production in Lactating Cows  

Microsoft Academic Search

Four, lactation dairy cows were randomly assigned according to a 2 x 2 Factorial arrangement in a 4 x 4 Latin square design to study supplementation of urea level (U) at 2 and 4 % and malate (M) at 10 and 20 g\\/hd\\/d in concentrate. The treatments were as follows U2M10, U2M20, U4M10 and U4M20, respectively. The cows were offered

2006-01-01

7

Formulated Milk Concentrate and Beverage.  

National Technical Information Service (NTIS)

The invention relates to a formulated milk concentrate prepared from nonfat dry milk (NFDM) solids, water, and edible oil by a simple, novel method without adding an emulsifier or using specialized dairy equipment such as homogenizers or colloid mills. Th...

G. N. Bookwalter, S. A. Lyle

1988-01-01

8

Voltamperometric Discrimination of Urea and Melamine Adulterated Skimmed Milk Powder  

PubMed Central

Nitrogen compounds like urea and melamine are known to be commonly used for milk adulteration resulting in undesired intoxication; a well-known example is the Chinese episode occurred in 2008. The development of a rapid, reliable and economic test is of relevance in order to improve adulterated milk identification. Cyclic voltammetry studies using an Au working electrode were performed on adulterated and non-adulterated milk samples from different independent manufacturers. Voltammetric data and their first derivative were subjected to functional principal component analysis (f-PCA) and correctly classified by the KNN classifier. The adulterated and non-adulterated milk samples showed significant differences. Best results of prediction were obtained with first derivative data. Detection limits in milk samples adulterated with 1% of its total nitrogen derived from melamine or urea were as low as 85.0 mg·L?1 and 121.4 mg·L?1, respectively. We present this method as a fast and robust screening method for milk adulteration analysis and prevention of food intoxication. PMID:23112709

Hilding-Ohlsson, Astrid; Fauerbach, Jonathan A.; Sacco, Natalia J.; Bonetto, M. Celina; Cortón, Eduardo

2012-01-01

9

Original article UHT processed milk concentrates  

E-print Network

Original article UHT processed milk concentrates Jörg HINRICHS* Chair for food process engineering osmosis concentrates made from milk with differing fat and protein contents were sheared in defined flow and storage stability correlated with the ash content and these increase as the ash contents decrease. Milk

Paris-Sud XI, Université de

10

Predialysis urea concentration is sufficient to characterize hemodialysis adequacy.  

PubMed

Mathematical description of urea kinetics for a week showed that, under steady state conditions (i.e., total removal equals total synthesis), any predialysis urea concentration is expressed as a linear function of specific urea generation (G/V) and of dialysis schedule timing and sessional Kt/V (product of clearance, K, and session time, t, divided by the urea distribution volume, V). It also predicts that TACurea is proportional to the predialysis concentrations. The ratio between the two depends linearly on delivered weekly dialysis dose ([wDD] = T(G/V)/TACurea, with T the number of hours in 1 week). These hypotheses have been tested by retrospectively analyzing urea kinetc modelling data that include all predialysis and post dialysis concentrations of 163 patient-weeks. All patients were anuric, and dialysis frequency was thrice weekly. Accuracy is assessed with regression analysis between database numbers and computed values. The theoretical ratio between midweek concentration and TACurea (1.43) is close to the computed ratio (1.46, r2 = 0.909). TACurea (slope = 1.002, r2 = 0.997), specific generation rate G/V as a precursor to PCRn (slope = 1.007, r2 = 0.985), and wDD (slope = 1.002, r2 = 0.909) are all accurately computed from predialysis concentrations. To aid in the determination of the ratio for the different predialysis, concentrations using wDD a nomogram is included. PMID:9804519

De Wachter, D S; Brems, S; Vanholder, R; Verdonck, P R; Hombrouckx, R O

1998-01-01

11

Using Milk Urea Nitrogen to Predict Nitrogen Excretion and Utilization Efficiency in Lactating Dairy Cows1  

Microsoft Academic Search

Because animal agriculture has been identified as a major source of nonpoint N pollution, ways to reduce the excretion of N by production animals must be examined. The objective of this research was to develop and evaluate a mathematical model that inte- grates milk urea N to predict excretion, intake, and utilization efficiency of N in lactating dairy cows. Three

J. S. Jonker; R. A. Kohn; R. A. Erdman

1998-01-01

12

Heat Resistance of Salmonellae in Concentrated Milk  

PubMed Central

The heat resistance of Escherichia coli, Salmonella typhimurium, and Salmonella alachua in milk solutions containing 10, 30, 42, and 51% (w/w) skim milk for total solids was determined. Increased milk-solids level effected a significant increase in the heat resistance of each organism. Although E. coli was more heat-resistant than both strains of Salmonella in 10% milk, the situation was reversed in 42 and 51% milk. Prior growth temperature was found to exert a profound effect on the heat resistance of S. typhimurium. Growth of S. typhimurium in 42% milk solids for 24 hr did not greatly enhance the thermal resistance of the organism when heated in a fresh 42% solids concentrate. Application of a partial vaccum during heating greatly diminished the decimal reduction times of S. typhimurium and E. coli and, in addition, virtually eliminated the protective effect of increased solids level. PMID:4552893

Dega, C. A.; Goepfert, J. M.; Amundson, C. H.

1972-01-01

13

Pressure-induced denaturation of ?-lactoglobulin in skim milk: effect of milk concentration.  

PubMed

The effect of milk concentration (10-40% TS) on the kinetics of the pressure-induced denaturation of ?-lactoglobulin (?-LG) was studied. The denaturation was found to be a second-order process at all milk concentrations and pressures. There was a change in pressure dependence of the rate constants for denaturation at about 300 MPa, and this effect became more pronounced as the milk concentration increased. At pressures ?300 MPa, a small effect of milk concentration was observed, with small decreases in the rate of denaturation as the milk concentration was increased above 20% TS. This was attributed to the lower pH as the milk concentration was increased. In contrast, at 200 MPa, ?-LG denaturation was markedly retarded as the milk solids concentration was increased. This was attributed to the increased lactose concentration at higher milk concentrations. This would promote ?-LG dimerization at this pressure and this would stabilize the ?-LG to denaturation. PMID:22676353

Anema, Skelte G

2012-07-01

14

Quantitative determination of urea concentrations in cell culture medium  

PubMed Central

Urea is the major nitrogenous end product of protein metabolism in mammals. Here, we describe a quantitative, sensitive method for urea determination using a modified Jung reagent. This assay is specific for urea and is unaffected by ammonia, a common interferent in tissue and cell cultures. We demonstrate that this convenient colorimetric microplate-based, room temperature assay can be applied to determine urea synthesis in cell culture. PMID:19448747

Zawada, Robert J.X.; Kwan, Peggy; Olszewski, Kellen L.; Llinas, Manuel; Huang, Shu-Gui

2009-01-01

15

Temporal and spatial dynamics of urea uptake and regeneration rates and concentrations in Chesapeake Bay  

Microsoft Academic Search

We examined the temporal and spatial variability of urea concentrations and urea uptake and regeneration rates collected on\\u000a cruises along the longitudinal axis of the Chesapeake Bay between 1972 and 1998. Interannually, mean Bay-wide surface urea\\u000a concentrations ranged between 0.49 and 0.91 ?g-at N l?1 with a nearly 50% decrease in surface concentrations observed between 1988 and 1998. Concentrations of

Michael W. Lomas; T. Mark Trice; Patricia M. Glibert; Deborah A. Bronk; James J. McCarthy

2002-01-01

16

The effect of urea infusion on the urinary concentrating mechanism in protein-depleted rats.  

PubMed Central

To explore the role of urea in the urinary concentrating mechanism, the contents of vasa recta, Henle's descending limbs and collecting ducts were sampled by micropuncture of the renal papilla before and after infusion of urea in 10 protein-depleted rats. Eight protein-depleted rats not given urea were similarly studied as a control group. After urea administration, osmolality and the concentrations of urea and nonurea solute of urine from both exposed and contralateral kideny increased significantly. The osmolality and urea concentration of fluid from the end of Henle's descending limb and vasa recta plasma and the tubule fluid-to-plasma inulin ratio in the end-descending limb all increased significantly after urea infusion. We interpret these observations to indicate that urea enhances urinary concentration by increasing the abstraction of water from the juxtamedullary nephron (presumably the descending limb), in agreement with the prediction of recent passive models of the urinary concentrating mechanism. However, the concentration of urea in fluid from the descending limb after urea infusion was high (261 plus or minus 31 mM) and the difference in solium concentration between descending limb fluid and vasa recta was small and statistically insignificant. PMID:1127107

Pennell, J P; Sanjana, V; Frey, N R; Jamison, R L

1975-01-01

17

ORIGINAL PAPER Post-processing of concentrated fermented milk: influence  

E-print Network

-dimensional network. In the milk gel, the clusters fuse to roughly homogeneous strands and cannot be (wellORIGINAL PAPER Post-processing of concentrated fermented milk: influence of temperature and holding of particle clusters in concentrated, fermented milk (protein content 8.2% (w/w)) during post

Paris-Sud XI, Université de

18

Role of urea in the postprandial urine concentration cycle of the insectivorous bat Antrozous pallidus.  

PubMed

Insectivorous bats, which feed once daily, produce maximally concentrated urine only after feeding. The role of urea as an osmolyte in this process was investigated in pallid bats (Antrozous pallidus) in the laboratory. Following a 24-h fast, plasma and urine were sampled before and 2 h after feeding in postprandial (PP) animals and before and 2 h after similar treatment without feeding in nonfed (NF) animals. Food consumption by PP animals and handling of NF animals had no effect on blood water content as measured by hematocrit and plasma oncotic pressure. Food consumption increased both plasma osmolality (P(osm)) and plasma urea (P(urea)) by as much as 15%. Food consumption also increased urine osmolality (U(osm)) and urine urea (U(urea)) by 50-100%. Feeding increased U(osm) regardless of changes in P(osm), and elevation of U(osm) resulted primarily from increased U(urea). In NF bats, P(osm) and P(urea) were unchanged, while U(osm) and U(urea) increased by as much as 25%. Again, increased U(osm) resulted primarily from increased U(urea). The PP urine concentration cycle of pallid bats resulted from increased urea excretion in response to apparent rapid urea synthesis. Bats rapidly metabolized protein and excreted urea following feeding when body water was most plentiful. PMID:15123201

Bassett, John E

2004-02-01

19

Pretreatment with hypertonic NaCl protects MDCK cells against high urea concentrations  

Microsoft Academic Search

In antidiuresis, the cells of the renal medulla are exposed to high extracellular concentrations of NaCl and urea. Since\\u000a urea equilibrates with the intracellular compartment and is known to perturb intracellular macromolecules, high urea concentrations\\u000a may well disturb the structure and function of cell proteins. Two types of organic substances are believed to counteract the\\u000a adverse effects of high intracellular

Wolfgang Neuhofer; E. Müller; Anke Burger-Kentischer; Maria-Luisa Fraek; Klaus Thurau; F.-X. Beck

1998-01-01

20

Endocrine regulation of calcium and phosphorus concentration in camel's milk.  

E-print Network

Endocrine regulation of calcium and phosphorus concentration in camel's milk. F Riad M Ben Goumi JCIAVHassan Il, Rabat, Maroc; 31NRA, Theix, France Some qualitative aspects of the milk of the dromedary suggest that the ability to produce milk of high nutritive value for offspring or for human beings during long periods

Paris-Sud XI, Université de

21

Effect of mastitis on milk perchlorate concentrations in dairy cows.  

PubMed

Recent surveys have identified the presence of perchlorate, a natural compound and environmental contaminant, in forages and dairy milk. The ingestion of perchlorate is of concern because of its ability to competitively inhibit iodide uptake by the thyroid and to impair synthesis of thyroid hormones. A recent study established that milk perchlorate concentrations in cattle highly correlate with perchlorate intake. However, there is evidence that up to 80% of dietary perchlorate is metabolized in clinically healthy cows, thereby restricting the available transfer of ingested perchlorate into milk. The influence of mastitis on milk perchlorate levels, where there is an increase in mammary vascular permeability and an influx of blood-derived components into milk, remains unknown. The present study examined the effect of experimentally induced mastitis on milk perchlorate levels in cows receiving normal and perchlorate-supplemented diets. Over a 12-d period, cows were ruminally infused with 1 L/d of water or water containing 8 mg of perchlorate. Five days after the initiation of ruminal infusions, experimental mastitis was induced by the intramammary infusion of 100 microg of bacterial lipopolysaccharide (LPS). Contralateral quarters infused with phosphate-buffered saline served as controls. A significant reduction in milk perchlorate concentration was observed in the LPS-challenged glands of animals ruminally infused with either water or perchlorate. In control glands, milk perchlorate concentrations remained constant throughout the study. A strong negative correlation was identified between mammary vascular permeability and milk perchlorate concentrations in LPS-infused glands. These findings, in the context of a recently published study, suggest that an active transport process is operative in the establishment of a perchlorate concentration gradient across the blood-mammary gland interface, and that increases in mammary epithelial and vascular endothelial permeability lead to a net outflow of milk perchlorate. The overall finding that mastitis results in lower milk perchlorate concentrations suggests that changes in udder health do not necessitate increased screening of milk for perchlorate. PMID:16840617

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

2006-08-01

22

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.

1968-01-01

23

Manufacture of low lactose concentrated ultrafiltered-diafiltered retentate from buffalo milk and skim milk.  

PubMed

Lactose concentration was reduced by 68.64 and 74.64 % in buffalo milk and skim milk by their respective 3.05 fold and 4.4 fold UF-DF concentration. The maximum UF-DF concentration of buffalo milk to 66.65 % volume reduction was observed as compared to 74.35 % volume reduction in buffalo skim milk. Average initial permeate flux rate of buffalo milk (42.86 l/h/m(2)) was much lower than skim milk (71.43 l/h/m(2)), which dropped to 2.86 and 5.95 l/h/m(2) during UF-DF concentration. The initial permeate flux rate of homogenized buffalo milk (26.79 l/h/m(2)) was comparatively lower than that of buffalo milk which dropped to 2.38 l/h/m(2) after 66.33 % volume reduction and 3.02 fold UF-DF concentration. PMID:24493903

Solanki, Puneet; Gupta, Vijay Kumar

2014-02-01

24

Effect of milk solids concentration on the pH, soluble calcium and soluble phosphate levels  

E-print Network

Note Effect of milk solids concentration on the pH, soluble calcium and soluble phosphate levels, the level of Casol and Psol, as mmol·kg-1 , increased and the pH decreased as the milk concentration as the milk concentration was increased. At any given milk concentration, the level of Casol, Psol and milk pH

Boyer, Edmond

25

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

2006-01-01

26

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

PubMed

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

2013-09-01

27

Calcium release from milk concentrated by ultrafiltration and diafiltration.  

PubMed

The present work studied the solubilization of Ca during acidification in milk concentrated by ultrafiltration (UF) and diafiltration (DF). The effect of heating milk at 80°C for 15min was also evaluated. In addition to measuring buffering capacity, the amount of Ca released as a function of pH was determined. The area of the maximum peak in buffering capacity observed at pH ~5.1, related to the presence of colloidal Ca phosphate, was significantly affected by casein volume fraction but did not increase proportionally with casein concentration. In addition, a lower buffering capacity and less solubilized Ca were measured in 2× DF milk compared with 2× UF milk. Heat treatment did not change the buffering capacity or Ca release in 1× and 2× concentrated milk. On the other hand, at a higher volume fraction (4×), more Ca was present in the soluble phase in heated 4× UF and DF milk compared with unheated milk. This is the first comprehensive study on the effect of concentration, distinguishing the effect of UF from that of DF, before and after heating, on Ca solubilization. PMID:25022683

Li, Y; Corredig, M

2014-09-01

28

The Comparative Value of Urea and Linseed Meal for Milk Production  

Microsoft Academic Search

In earlier work (5), we established the fact that for the growth of calves urea nitrogen could be successfully used for at least a partial supply of the protein nitrogen. This protein supply, from such a simple substance as urea, was made possible through the multiplication of the microorganisms of the rumen. This intervention of microorganisms and the use of

I. W. Rupel; G. Bohstedt; E. B. Hart

1943-01-01

29

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

1991-01-01

30

Changes in the concentrations of glucose, non-esterifed fatty acids, urea, insulin,  

E-print Network

Changes in the concentrations of glucose, non-esterifed fatty acids, urea, insulin, cortisol (Ca), phosphorus (P), magnesium (Mg) and cortisol were studied. The concentrations of NEFA, cortisol the expulsion of foetuses, NEFA and cortisol levels increased (+18 and +30 %, respectively), and they decreased

Paris-Sud XI, Université de

31

Plasma urea, creatinine and uric acid concentrations in response to dehydration in racing pigeons (Columba Livia Domestica)  

Microsoft Academic Search

Plasma urea, creatinine and uric acid concentrations were determined in six racing pigeons that had been deprived of water for 3 days. Plasma urea concentration showed a 6.5? to 15.3?fold increase, creatinine a 1.2? to 1.5?fold increase and uric acid a 1.4? to 2?fold increase when compared with values before water deprivation. Although these increases were significant, plasma urea and

J. T. Lumeij

1987-01-01

32

Role of urea in the postprandial urine concentration cycle of the insectivorous bat Antrozous pallidus  

Microsoft Academic Search

Insectivorous bats, which feed once daily, produce maximally concentrated urine only after feeding. The role of urea as an osmolyte in this process was investigated in pallid bats (Antrozous pallidus) in the laboratory. Following a 24-h fast, plasma and urine were sampled before and 2 h after feeding in postprandial (PP) animals and before and 2 h after similar treatment

John E Bassett

2004-01-01

33

Automatic On-Line Analysis Of Milk Constituents (Urea, Ketones, Enzymes And Hormones) Using Biosensors  

Microsoft Academic Search

:   Traditional methods of monitoring health changes in animals are based entirely on the human senses. However, in modern dairy\\u000a production systems humans are rarely present, this is particularly the case with the introduction of robotic milking. In these\\u000a systems all the functions of milking are automated and cows visit at times of their own choosing. Systems of automatic health

T. Mottram; M. Velasco-Garcia; P. Berry; P. Richards; J. Ghesquiere; L. Masson

2002-01-01

34

Concentration dependence of the subunit association of oligomers and viruses and the modification of the latter by urea binding.  

PubMed Central

A theoretical model is presented that accounts for the facilitation of the pressure dissociation of R17 phage, and for the partial restoration of the concentration dependence of the dissociation, by the presence of subdenaturing concentrations of urea. As an indifferent osmolyte urea should promote the stability of the protein aggregates under pressure, and the decrease in pressure stability with urea concentration demonstrates that such indirect solvent effects are not significant for this case, and that the progressive destabilization is the result of direct protein-urea interactions. By acting as a "homogenizer" of the properties of the phage particles, urea addition converts the pressure-induced deterministic dissociation of the phage into a limited stochastic equilibrium. The model establishes the origin of the uniform progression from the stochastic equilibrium of dimers, to the temperature-dependent and partially concentration-dependent association of tetramers, to the fully deterministic equilibrium observed in many multimers and in the virus capsids. PMID:8770195

Weber, G; Da Poian, A T; Silva, J L

1996-01-01

35

Effect of elevated systemic concentrations of ammonia and urea on the metabolite and ionic composition of oviductal fluid in cattle.  

PubMed

High dietary protein leads to elevated systemic concentrations of ammonia and urea, and these, in turn, have been associated with reduced fertility in cattle. The effect of elevating systemic concentrations of ammonia and urea on the concentrations of electrolytes and nonelectrolytes in bovine oviductal fluid were studied using estrus-synchronized, nulliparous heifers (n = 25). Heifers were randomly assigned to 1 of 3 treatments consisting of jugular vein infusion with either ammonium chloride (n = 8), urea (n = 8), or saline (n = 9). Oviducts were catheterized, and fluid was recovered over a 3-h period on either Day 2 or 8 of the estrous cycle. No difference (P > 0.05) was found in the concentrations of any electrolyte or nonelectrolyte between oviducts ipsi- or contralateral to the corpus luteum. Plasma and oviductal concentrations of urea were increased by infusion with urea (P < 0.001) and ammonium chloride (P < 0.05) but not by saline (P > 0.05). Plasma and oviductal concentrations of ammonia were elevated by infusion with ammonium chloride (P < 0.001) but not by infusion with urea or saline (P > 0.05). No effect (P > 0.05) of treatment was found on oviductal or plasma concentrations of glucose, lactate, magnesium, potassium, or sodium or on plasma concentrations of insulin or progesterone. The concentration of calcium in oviductal fluid was reduced by urea infusion and was negatively associated with systemic and oviductal concentrations of urea. Oviductal concentrations of sodium were higher on Day 8 than on Day 2 (P < 0.05). No effect of sample day was found on any of the other electrolytes or nonelectrolytes measured (P > 0.05). Elevated systemic concentrations of ammonia and urea are unlikely to reduce embryo survival through disruptions in the oviductal environment. PMID:12021065

Kenny, D A; Humpherson, P G; Leese, H J; Morris, D G; Tomos, A D; Diskin, M G; Sreenan, J M

2002-06-01

36

Use of Dry Milk Protein Concentrate in Pizza Cheese Manufactured by Culture or Direct Acidification  

Microsoft Academic Search

Milk protein concentrate (MPC) contains high con- centrations of casein and calcium and low concentra- tions of lactose. Enrichment of cheese milk with MPC should, therefore, enhance yields and improve quality. The objectives of this study were: 1) to compare pizza cheese made by culture acidification using standard- ized whole milk (WM) plus skim milk (SM) versus WM plus MPC;

Shakeel-Ur-Rehman; N. Y. Farkye; B. Yim

2003-01-01

37

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. PMID:22491419

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

2012-01-01

38

Effects of treating rice straw with urea or urea and calcium hydroxide upon intake, digestibility, rumen fermentation and milk yield of dairy cows  

Microsoft Academic Search

Three, multiparous Holstein crossbred dairy cows with initial body weight of 385±19 kg were randomly allocated to 3 treatments of rice straw (T1 = untreated rice straw; T2 = 5.5% urea-treated rice straw (5 g urea in 100 ml water to 100 g air-dry (91% DM) straw); T3 = 2.2% urea+2.2% calcium hydroxide treated rice straw (2.0 g urea and 2.0 g Ca(OH)2 in 100 ml to

Metha Wanapat; Sineenart Polyorach; Kitsada Boonnop; Chaowarit Mapato; Anusorn Cherdthong

2009-01-01

39

Milk Production and Milk Component of 75% Holstein Crossbred under Total Mixed Ration Feeding Management  

Microsoft Academic Search

The experiment was conducted to evaluate milk yield, milk component and cost of milk production from feeding 3 different total mixed rations (TMR) containing 3 different roughages. Urea-treated rice straw (UTS) was used in ration ?, UTS and Ruzi silage (1:1 by DM weight) and Ruzi silage were used in ration ?? and ???. The same concentrate mix was used

Damrus Chatreewong; Boonserm Cheva-Isarakul; Boonloom Cheva-Isarakul; Somkid Promma

40

Raised sodium, potassium, and urea concentrations in spermatic venous blood: an additional causative factor in the testicular dysfunction of varicocele?  

PubMed

The concentrations of Na, K, Cl, HCO3, LA, and urea, with calculation of the AG, as indirect indices of electrolyte balance and metabolic conditions prevailing in testicular environment, were determined in PB and SVB of 24 men with varicocele and 15 men with inguinal hernia. Significantly higher concentrations of Na, K, and urea were found in SVB as compared with PB values (P less than 0.001 for all) of patients with varicocele, but not in control subjects. The SVB concentrations of Na, K, and urea in varicocele patients were higher than SVB and PB concentrations of the control group (P less than 0.001 for all). It is concluded that urea, Na, and K concentrations are raised in SVB of patients with varicocele; this imbalance may be related, among other factors, to the pathogenesis of dyspermia in varicocele. PMID:3609346

Adamopoulos, D A; Kontogeorgos, L; Abrahamian-Michalakis, A; Terzis, T; Vassilopoulos, P

1987-08-01

41

Effect of solids concentration on the rheology of labneh (concentrated yogurt) produced from sheep milk  

Microsoft Academic Search

The effect of solids concentration on the apparent viscosity of labneh made from sheep milk has been investigated using a rotary viscometer. Sheep labneh was manufactured following the traditional method by using cloth bags. Apparent viscosity of labneh with four different solids concentration was studied as a function of the shear rate. It is found that sheep labneh with different

Hazim A. Mohameed; Basim Abu-Jdayil; Ali Al-Shawabkeh

2004-01-01

42

Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration  

SciTech Connect

Four multiple-cannulated steers (340 kg) were used in a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments. Steers were fed a diet of 50% ground hay and 50% concentrate at two intakes (1.4 and 2.1% of BW), with urea and /sup 15/N-enriched ammonium sulfate infused continuously into the rumen at .4 or 1.2% of diet DM. Ratios of purines and diaminopimelic acid-N to N in fluid-associated and particulate-associated bacteria and in protozoa were similar among treatments but were lower for protozoa than for bacteria. Diaminopimelic acid-N:N was higher for fluid-associated vs. particulate-associated bacteria. Enrichment of /sup 15/N was similar between bacteria among treatments and was 30% lower for protozoa. Turnover rates of /sup 15/N in bacteria, NH/sub 3/N, and non-HN/sub 3/N pools were faster for steers infused with 1.2 than those infused with .4% urea, indicating less efficient usage of ammonia with higher urea. A method is described to estimate the proportion of duodenal nitrogen comprising bacterial and protozoal nitrogen.

Firkins, J.L.; Berger, L.L.; Merchen, N.R.; Fahey, G.C. Jr.; Mulvaney, R.L.

1987-11-01

43

Genetic and nongenetic variation in plasma and milk ?-hydroxybutyrate and milk acetone concentrations of early-lactation dairy cows.  

PubMed

This study assessed genetic variation, heritability estimates, and genetic correlations for concentrations of plasma ?-hydroxybutyrate (BHBA), milk BHBA, and milk acetone in early lactation to investigate differences between cows in susceptibility to hyperketonemia and possibilities to use test-day milk ketone bodies for genetic improvement. Blood and test-day milk samples were collected on randomly selected dairy farms in the Netherlands from cows of various parities between 5 and 60 d in milk. Plasma samples were analyzed for BHBA (reference test for hyperketonemia) and test-day milk samples were analyzed for BHBA and acetone using Fourier-transform infrared spectroscopy. The final data set consisted of plasma BHBA concentrations of 1,615 cows from 122 herds. Milk BHBA and milk acetone concentrations were determined for 1,565 cows. Genetic variation, heritability, and proportion of phenotypic variation attributable to the herd were estimated using an animal model with fixed effects for parity and season, a covariate for days in milk, and random effects for herd, animal, and error. Genetic correlations for plasma BHBA, milk BHBA, and milk acetone were estimated using bivariate analyses. The heritability estimate for plasma BHBA concentrations in early lactation was 0.17, whereas heritability estimates for milk BHBA and milk acetone were 0.16 and 0.10, respectively. This indicates that selective breeding may contribute to a lower incidence of hyperketonemia in early lactation. For the 3 traits, the proportion of variance attributable to herd was larger than the additive genetic variance, underlining the importance of on-farm feeding and management in the etiology of hyperketonemia in fresh cows. Prevention strategies for hyperketonemia can, therefore, include both feeding and management strategies at dairy farms (short-term) and genetic improvement through breeding programs (long-term). Genetic correlations between concentrations of plasma BHBA and milk BHBA (0.52) or milk acetone (0.52) were moderate. As milk ketone bodies can be routinely analyzed at test days, this may provide a practical alternative for breeding programs aimed at reducing hyperketonemia in early lactation. PMID:22939798

van der Drift, S G A; van Hulzen, K J E; Teweldemedhn, T G; Jorritsma, R; Nielen, M; Heuven, H C M

2012-11-01

44

Technical note: Effect of determining baseline plasma urea nitrogen concentrations on subsequent posttreatment plasma urea nitrogen concentrations in 20- to 50-kilogram pigs.  

PubMed

Plasma urea N (PUN) has been used as an indicator of AA requirements and efficiency of AA utilization in swine. However, PUN concentrations vary among a population of pigs, even a population with a close range of BW and fed the same diet. Thus, pretreatment or baseline PUN concentrations are used as a covariate to reduce variation of posttreatment PUN. However, this procedure increases experimental costs and stress to the pigs. Data from 14 experiments (26 to 28 d in duration) conducted using PUN as a response variable were compiled into 1 data set. Each experiment had 4 to 6 treatments. The purpose of this technical report was to summarize the effect of determining pretreatment baseline PUN concentrations on subsequent posttreatment PUN concentrations in 20- to 50-kg pigs. In all experiments, pigs were fed corn- and soybean meal-based diets and low-CP diets with various AA additions; pigs were assigned to dietary treatments in a randomized complete block design with a minimum of 4 replicates of 3 to 5 pigs each. Before the start of each experiment, all pigs were fed a common diet for a minimum of 3 d. Blood samples were collected from each pig before allotment to dietary treatments (d 0) and at the end of each experiment. The baseline (d 0) PUN was analyzed as a covariate for posttreatment PUN. Data from each experiment were analyzed without and with baseline PUN in the statistical model. In all experiments combined, there were 768 possible treatment comparisons. The covariate baseline PUN was statistically significant (P < 0.10) in 9 of 14 experiments. However, only 8 treatment differences changed statistical significance as a result of analyzing the data with baseline PUN as a covariate. These 8 treatment differences were in 3 experiments. These results indicate that it is not always necessary to determine baseline PUN concentrations when feeding diets with large differences in AA content. PMID:21821811

Waguespack, A M; Powell, S; Roux, M L; Frugé, E D; Bidner, T D; Payne, R L; Southern, L L

2011-12-01

45

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

PubMed

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

2011-09-01

46

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.

1986-03-01

47

Concentrations of vitamin C in plasma and milk of dairy cattle  

E-print Network

Note Concentrations of vitamin C in plasma and milk of dairy cattle M Hidiroglou, M Ivan, TR Batra and analyzed for vitamin C (ascorbic acid). At birth, the blood plasma concentration of ascorbic acid in calves approximately 28 d after calving. dairy cattle / vitamin C / blood plasma /milk Résumé — Concentration en

Paris-Sud XI, Université de

48

Effects of Standardization of Whole Milk with Dry Milk Protein Concentrate on the Yield and Ripening of Reduced-Fat Cheddar Cheese  

Microsoft Academic Search

Commercial milk protein concentrate (MPC) was used tostandardize wholemilk forreduced-fat Cheddar cheesemaking. Four replicate cheesemaking trials of three treatments (control, MPC1, and MPC2) were con- ducted. The control cheese (CC) was made from stan- dardized milk (casein-to-fat ratio, C\\/F ?1.7) obtained by mixing skim milk and whole milk (WM); MPC1 and MPC2 cheeses were made from standardized milk (C\\/ F

Shakeel Ur Rehman; N. Y. Farkye; T. Considine; A. Schaffner; M. A. Drake

2003-01-01

49

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

2007-01-01

50

Effect of sorbitol and inositol on the critical micelle concentration of nonionic surfactants in water and in aqueous urea  

Microsoft Academic Search

Summary The critical micelle concentrations (cmc) of non-ionic surfactants in water and in aqueous urea with or without hexahydric alcohols, sorbitol and inositol, were determined. In water the cmc's of the surfactants were decreased by the addition of the hexahydric alcohols. In addition, there was a remarkable difference in the decreasing ability between these two hexahydric alcohols. Inositol decreased the

M. Ueda; T. Urabata; A. Katayama; N. Kuroki

1979-01-01

51

Effects of dietary vitamin E concentration and source on sow, milk, and pig concentrations of ?-tocopherol.  

PubMed

A total of 126 gilts and sows (PIC 1050) and their litters were used to determine the effects of dietary vitamin E concentration and source on sow plasma, milk, and pig concentrations of ?-tocopherol. Additionally, we estimated the bioavailability of D-?-tocopheryl acetate (D-?-TAc) relative to DL-?-tocopheryl acetate (DL-?-TAc) when fed in diets containing dried distillers grains with solubles (DDGS). The 6 dietary treatments included DL-?-TAc at 44 and 66 mg/kg and D-?-TAc at 11, 22, 33, and 44 mg/kg. From breeding to d 69 of gestation, sows were fed 2.0 kg/d of a diet containing 40% DDGS, 0.30 mg/kg added Se, and no added vitamin E. Vitamin E treatments were fed from d 70 of gestation through weaning. Plasma was collected from sows on d 69 and 100 of gestation, at farrowing, and at weaning. Colostrum and milk samples were also collected. Plasma from 3 pigs per litter and heart and liver samples from 1 pig per litter were collected at weaning. Plasma, milk, and tissues from 6 litters per treatment were analyzed for ?-tocopherol. Although tissue, plasma, and milk concentrations of ?-tocopherol were the primary response criteria of interest, sow and litter performance were measured. As expected, treatment effects were not observed for lactation feed intake, sow BW, or backfat measurements. A trend (P = 0.085) for a treatment effect on average pig BW at weaning was detected, with pigs nursing sows fed 44 mg/kg DL-?-TAc weighing less because of a younger weaning age. No other differences in litter performance were observed. As D-?-TAc increased in the diet, sow plasma, colostrum, and milk, pig plasma, and pig heart concentrations of ?-tocopherol increased (linear, P < 0.03). Sows fed diets with 44 mg/kg D-?-TAc had increased (P < 0.03) plasma and colostrum and pig plasma concentrations of ?-tocopherol compared with sows fed 44 mg/kg of DL-?-TAc. Sows fed 66 mg/kg DL-?-TAc also had greater (P = 0.022) plasma ?-tocopherol at weaning than sows fed 44 mg/kg DL-?-TAc. Bioavailability coefficients for D-?-TAc relative to DL-?-TAc ranged from 1.9 to 4.2 for sow and pig plasma ?-tocopherol, 2.9 to 3.6 for colostrum ?-tocopherol, 1.6 for milk ?-tocopherol, and 1.7 to 2.0 for pig heart and liver ?-tocopherol. Overall, this study indicates the bioavailability for D-?-TAc relative to DL-?-TAc varies depending on the response criteria but is greater than the standard potency value of 1.36. PMID:25267996

Shelton, N W; Dritz, S S; Nelssen, J L; Tokach, M D; Goodband, R D; DeRouchey, J M; Yang, H; Hill, D A; Holzgraefe, D; Hall, D H; Mahan, D C

2014-10-01

52

Concentrations of Sialyloligosaccharides in Bovine Colostrum and Milk during the Prepartum and Early Lactation  

Microsoft Academic Search

Sialyloligosaccharides and sialylglycoconjugates in colostrumandmilkareregardedtobeimportantbiolog- ical components with respect to be source of brain gan- gliosides in infant and to be antiinfectional components for the attack by the pathogenic bacteria and virus. Severalacidicoligosaccharideshavebeencharacterised inbothbovineandhumanmilkorcolostrum.Thesialyl- oligosaccharide content of human colostrum and milk has been extensivelystudied, whereas that ofcows milk andcolostrumhasreceivedless attention.Inthisstudy, the concentrations of three sialyloligosaccharides of bo- vine colostrum and

T. Nakamura; H. Kawase; K. Kimura; Y. Watanabe; M. Ohtani; I. Arai; T. Urashima

2003-01-01

53

Profitability of replacing milk with a concentrate for calves of cows requiring calf at foot for milking  

Microsoft Academic Search

During a 90-d study in Mali, West Africa, 18 zebu and zebu by Montbeliard calves, age 50 ± 23 d (youngest pair 3 weeks), weighing 30 ± 7 kg, under farmer management, were used to test the profitability of replacing suckled milk by a maize-groundnut cake-rice bran concentrate fed dry. During the first 45 d period there were no differences

B. Ouologuem; Alice A. Reese; B. Traoré; S. K. Debrah

1994-01-01

54

Concentration of Trichloroethylene in Breast Milk and Household Water from Nogales, Arizona  

PubMed Central

The United States Environmental Protection Agency has identified quantification of trichloroethylene (TCE), an industrial solvent, in breast milk as a high priority need for risk assessment. Water and milk samples were collected from 20 households by a lactation consultant in Nogales, Arizona. Separate water samples (including tap, bottled and vending machine) were collected for all household uses: drinking, bathing, cooking, and laundry. A risk factor questionnaire was administered. Liquid-liquid extraction with diethyl ether was followed by GC-MS for TCE quantification in water. Breast milk underwent homogenization, lipid hydrolysis and centrifugation prior to extraction. The limit of detection was 1.5 ng/mL. TCE was detected in 7 of 20 mothers’ breast milk samples. The maximum concentration was 6 ng/mL. TCE concentration in breast milk was significantly correlated with the concentration in water used for bathing (?=0.59, p=0.008). Detection of TCE in breast milk was more likely if the infant had a body mass index <14 (RR=5.2, p=0.02). Based on average breast milk consumption, TCE intake for 5% of the infants may exceed the proposed US EPA Reference Dose. Results of this exploratory study warrant more in depth studies to understand risk of TCE exposures from breast milk intake. PMID:22827160

Beamer, Paloma I.; Luik, Catherine E.; Abrell, Leif; Campos, Swilma; Martínez, María Elena; Sáez, A. Eduardo

2013-01-01

55

Concentration profiles of metals in breast milk, drinking water, and soil: relationship between matrices.  

PubMed

The concentrations of Cd, Cr, Cu, Hg, Mn, Ni, Pb, Sn, and Zn were determined in breast milk of women living in Conceição das Alagoas, Minas Gerais, Brazil. The potential relationships between metal levels in samples of breast milk, drinking water, and soils collected in the study area were also established. Metal levels in breast milk, except Cr, were lower in comparison to WHO reference concentrations. Zinc was the predominant element in breast milk and drinking water samples, with a median level of 46.2 and 82.2 ?g · L(-1), respectively. Soils presented a different pattern of metal concentrations with respect to those found in breast milk and drinking water, Chromium showed the highest median levels (148 mg · kg(-1)), while a certain predominance of Zn and Cu was also observed (47.0 and 43.0 mg · kg(-1), respectively). Similar profiles were observed when comparing metal concentrations in drinking water and breast milk (chi-square ?(2)?= 14.36; p < 0.05). In contrast, breast milk-soil and drinking water-soil metal concentration profiles showed significant differences (?(2)?= 635.05 and ?(2)?= 721.78, respectively; p < 0.05). These results indicate that drinking water is an important exposure pathway for metals to newborns through breast milk. Further studies should be aimed at assessing the body burdens of metals in that population and at evaluating the potential relationships in the concentrations in biological and environmental matrices as well as at estimating the contribution of dietary intake of metals. In addition, the presence of other chemical pollutants in breast milk should be also studied in order to assess the combined newborn exposure to other contaminants. PMID:24881955

Cardoso, Osmar O; Julião, Fabiana C; Alves, Renato I S; Baena, Antonio R; Díez, Isabel G; Suzuki, Meire N; Celere, Beatriz S; Nadal, Martí; Domingo, José L; Segura-Muñoz, Susana I

2014-07-01

56

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

1999-01-01

57

Milk Synthetic Response of the Bovine Mammary Gland to an Increase in the Local Concentration of Amino Acids and Acetate  

Microsoft Academic Search

Rates of secretion of components into milk are a func- tion of precursor concentrations and parameters that describe expression of the milk synthetic enzymes and their sensitivity to precursor concentrations. To estab- lish the enzymatic sensitivities of milk fat yield and mammary acetate utilization to circulating acetate con- centration, lactating cows were infused for 10 h with 0 or 40

N. G. Purdie; D. R. Trout; D. P. Poppi; J. P. Cant

2008-01-01

58

THE EFFECT OF I-IIGH-TEMPERATU RE-SHORT-TIME HEATING OF CONCENTRATED MILK UPON ITS HEAT STABILITY  

Microsoft Academic Search

In the manufacture of evaporated milk the raw milk is always fore- warmed to protect it against bacterial and enzymic action and to control the heat stability of its concentrate during sterilization. \\

B. H. WEBB; R. W. BELL

59

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.

1987-11-01

60

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. PMID:24066011

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

2013-01-01

61

Maternal Diet and Selenium Concentration in Human Milk From an Italian Population  

PubMed Central

Background Low selenium (Se) status is associated with several diseases. International organizations have proposed intakes of Se for general populations, including infants. Studies of the association of Se concentration in breast milk and maternal diet have yielded inconsistent results. We evaluated the relation between the intake of food items during pregnancy and Se concentration in human milk after delivery and compared infant intake of Se from breast milk with the recommended intakes. Methods This cross-sectional study was part of the baseline assessment of a prospective cohort of Italian mother–child pairs enrolled in 1999–2001. Se concentration was measured in the milk of 100 women included in the cohort and correlated with the intake of food items during pregnancy and lactation as reported in a food frequency questionnaire. Results Among foods consumed in pregnancy, only eggs had a positive, but weak, correlation with Se concentration in milk (r = 0.20, P = 0.04). Fish intake during lactation was also weakly correlated with Se in milk (r = 0.21, P = 0.04). Se content of breast milk in our population was lower than that noted in other international studies; however, very few children who were exclusively breastfed were estimated not to have met the recommended Se intake. Conclusions Future research should aim to verify whether infants in this part of Italy still meet the recommended nutrient intake of Se and to assess the influence of the concurrent diet of lactating mothers on the Se content of their milk. PMID:21628842

Valent, Francesca; Horvat, Milena; Mazej, Darja; Stibilj, Vekoslava; Barbone, Fabio

2011-01-01

62

Effect of Dietary Vitamin C on Concentrations of Ascorbic Acid in Plasma and Milk1  

Microsoft Academic Search

The addition of exogenous ascorbic acid to milk re- duces the development of oxidized flavor. This experi- ment was conducted to determine whether feeding ascorbic acid to cows influenced vitamin C concentra- tions in milk. Thirty-two midlactation Holstein cows were fed a basal diet of 56% forage, 36.6% concentrate, and 7.4% roasted whole soybeans (dry basis) that was top-dressed with

W. P. Weiss

2001-01-01

63

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

2011-01-01

64

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

PubMed

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 20 mg d(-1) for cows, low iodine dietary intake (<1.5 mg d(-1)) resulted in a reduced transfer of radioiodine to milk by 25%, varying stable iodine intakes in the range of 10-500 mg d(-1) did have no significant effect; at stable iodine intake rates above 1000 mg I d(-1), a reduction by a factor of approximately two was achieved. The high dietary iodine intakes--being about 100 times the normal iodine supply--required to reduce the radioiodine transfer significantly, will result in stable iodine concentrations in milk in excess of advised or legal limits for human consumption. Nevertheless, the provision of stable iodine via the milk pathway might be considered for emergency situations when stable iodine is used as a preventative measure for dose reduction to humans. PMID:17707560

Voigt, G; Kiefer, P

2007-01-01

65

Arsenic Concentrations in Water, Soil, Milk and Forage in Comarca Lagunera, Mexico  

Microsoft Academic Search

Arsenic levels were determined in seventy three samples of well water, and in fifty samples of soil, forage and cow's milk collected at the most important dairy farms of the Comarca Lagunera located in Coahuila and Durango, Mexico, region naturally rich in As. The total inorganic arsenic concentration in well water ranged from 7 to 740 µg L-1 and about

I. Rosas; R. Belmont; A. Armienta; A. Baez

1999-01-01

66

The safety of whey protein concentrate derived from the milk of cows immunized against Clostridium difficile  

Microsoft Academic Search

A whey protein concentrate prepared from the milk of cows that have been immunized against Clostridium difficile (C. difficile) and its toxins, toxin A and toxin B, is produced for use as a medical food for the dietary management of patients with C. difficile-associated diarrhea (CDAD) to prevent a relapse of the infection. The safety of anti-C. difficile whey protein

Karen W. H. Young; Ian C. Munro; Steve L. Taylor; Peter Veldkamp; Jaap T. van Dissel

2007-01-01

67

Growth hormone releasing factor and somatostatin concentrations in the milk of lactating women  

Microsoft Academic Search

The concentrations of growth hormone releasing factor (GRF) and somatostatin, two hypothalamic neuropeptides involved in the regulation of growth hormone secretion, were measured in human milk samples. The study was performed in healthy women within 48 h of delivery or during established lactation (between 1 and 64 weeks post delivery). No statistically significant correlation was found between the levels in

H. Werner; P. Katz; M. Fridkin; Y. Koch; S. Levine

1988-01-01

68

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

2004-01-01

69

Diet digestibility and growth of holstein calves fed acidified milk replacers containing soy protein concentrate.  

PubMed

Three experiments were conducted to determine the effects of acidification of milk replacers containing soy protein concentrate on diet digestibility and growth of Holstein bull calves. In Experiment 1, six calves (6 wk old) were fed at 10% of BW/d either acidified milk replacer containing soy protein concentrate or untreated milk replacer containing soy protein concentrate. Replacers were reconstituted to 12.5% DM for 10-d adjustment and 4-d collection periods to determine digestibility and N balance. Digestibilities of DM, ether extract, and N were similar between treatments. Nitrogen retention and N retention as a percentage of that absorbed were higher for calves fed the acidified diet. In Experiment 2, 20 calves (1 wk old) were fed diets identical to those diets fed in Experiment 1 at 20% of BW/d for 4 wk. Calves were allowed to adjust to the diet for 5 d. Growth parameters were measured and amount of feed offered was adjusted weekly. Calves fed the untreated diet had higher daily weight gains, girth gains, height gains, and better feed utilization. In Experiment 3, 21 calves were fed either the aforementioned diets or a replacer based on milk proteins at 10% of BW/d (12.5% DM) for 4 wk. Growth parameters were measured and DM intakes were adjusted weekly. Growth and feed conversion were similar across diets. Replacers containing soy protein concentrate or large amounts of whey may need to be supplemented with additional methionine to maximize rate of gain. PMID:2760313

Erickson, P S; Schauff, D J; Murphy, M R

1989-06-01

70

Refractometer assessment of colostral and serum IgG and milk total solids concentrations in dairy cattle  

PubMed Central

Background Estimation of the quantity of colostral IgG or serum IgG absorbed following ingestion of colostrum by calves is essential for monitoring the effectiveness of colostrum feeding practices on dairy farms. Milk total solids concentrations determination is a critical part of quality assessment of nonsaleable whole milk prior to feeding to calves. To date, on-farm methods to assess colostral IgG, serum IgG or milk total solids concentrations have been performed separately with various instruments. The objective of this study was to evaluate the diagnostic performance of a single electronic, hand-held refractometer for assessing colostral and serum IgG concentrations and milk total solids in dairy cattle. Colostral IgG, serum IgG and milk total solids concentrations were determined by the refractometer. Corresponding analysis of colostral and serum IgG concentrations were determined by radial immunodiffusion (RID) while milk total solids were determined by spectrophotometry. Sensitivity and specificity of the refractometer for colostrum and serum samples were calculated as determined by RID. Sensitivity and specificity of the refractometer for milk samples was calculated as determined by spectrophotometry. Results The sensitivity of the refractometer was 1 for colostral IgG, serum IgG and milk total solids determinations. Specificity of the refractometer was 0.66, 0.24 and 0 for colostral IgG, serum IgG and milk total solids determinations, respectively. The refractometer underestimated colostral IgG, serum IgG and milk total solids concentrations compared to the concentrations determined by RID or spectrophotometry. Conclusions The refractometer was an acceptable, rapid, convenient on-farm method for determining colostral IgG and milk total solids. The refractometer was not an acceptable method for determination of serum IgG concentrations as it severely underestimated the serum IgG concentrations. PMID:25125217

2014-01-01

71

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.

2013-03-01

72

Milk Production of Dairy Cows Fed Differing Concentrations of Rumen-Degraded Protein1  

Microsoft Academic Search

Thirty-two multiparous and 16 primiparous Holstein cows in midlactation averaging 126 d in milk were used to determine the effects of rumen-degraded protein (RDP) concentration on lactation performance. Cows wereassignedtodietsinarepeatedLatinsquaredesign with 3-wk experimental periods. Diets were formulated to provide 4 concentrations of dietary RDP (6.8, 8.2, 9.6, and 11.0% of dry matter (DM)) while rumen-unde- graded protein remained constant (5.8%

K. F. Kalscheur; R. L. Baldwin VI; B. P. Glenn; R. A. Kohn

2006-01-01

73

Influence of prematurity and birth weight on the concentration of ?-tocopherol in colostrum milk  

PubMed Central

OBJECTIVE: To assess vitamin E levels in the breast milk, analyzing the prematurity and the birth weight influence in ?-tocopherol concentration of colostrum milk. METHODS: Cross-sectional study, in which the colostrum was collected from 93 nursing mothers in a public maternity of Natal, Rio Grande do Norte, Northeast Brazil. The newborns were classified based on gestational age and birth weight. The analysis of ?-tocopherol in the milk was carried out by high performance liquid chromatography. RESULTS: The ?-tocopherol concentration in the colostrum of lactating women whose children were born at term was 1,093.6±532.4µg/dL; for preterm infants, the concentration was 1,321.6±708.5µg/dL (p=0.109). In the preterm group, the ?-tocopherol concentration in the colostrum of lactating women whose children were born with low and normal birth weight was 1,316.0±790.7 and 1,327.2±655.0µg/dL, respectively (p=0.971). In the term group, the ?-tocopherol levels were higher in mothers of children with birth weight >4000g, being 1,821.0±575.4µg/dL, compared to 869.5±532.1µg/dL and 1,039.6±477.5µg/dL with low and adequate birth weight, respectively (p>0.05). CONCLUSIONS: Prematurity did not influence ?-tocopherol levels in the colostrum milk. Mothers who had macrossomic term neonates presented increased ?-tocopherol levels. These results indicate that birth weight can influence ?-tocopherol leves in the colostrum milk. PMID:24473952

Grilo, Evellyn Camara; de Lira, Larissa Queiroz; Dimenstein, Roberto; Ribeiro, Karla Danielly da S.

2013-01-01

74

Determination of perfluorinated alkyl acid concentrations in human serum and milk standard reference materials.  

PubMed

Standard Reference Materials (SRMs) are certified reference materials produced by the National Institute of Standards and Technology that are homogeneous materials well characterized with values for specified properties, such as environmental contaminant concentrations. They can be used to validate measurement methods and are critical in improving data quality. Disagreements in perfluorinated alkyl acid (PFAA) concentrations measured in environmental matrices during past interlaboratory comparisons emphasized the need for SRMs with values assigned for PFAAs. We performed a new interlaboratory comparison among six laboratories and provided, for the first time, value assignment of PFAAs in SRMs. Concentrations for perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and other PFAAs in two human serum and two human milk SRMs are reported. PFAA concentration measurements agreed for serum SRM 1957 using different analytical methods in six laboratories and for milk SRM 1954 in three laboratories. The interlaboratory relative standard deviation for PFOS in SRM 1957 was 7%, which is an improvement over past interlaboratory studies. Matrix interferences are discussed, as well as temporal trends and the percentage of branched vs. linear isomers. The concentrations in these SRMs are similar to the present-day average concentrations measured in human serum and milk, resulting in representative and useful control materials for PFAA human monitoring studies. PMID:19862506

Keller, Jennifer M; Calafat, Antonia M; Kato, Kayoko; Ellefson, Mark E; Reagen, William K; Strynar, Mark; O'Connell, Steven; Butt, Craig M; Mabury, Scott A; Small, Jeff; Muir, Derek C G; Leigh, Stefan D; Schantz, Michele M

2010-05-01

75

Transfer of aflatoxin B1 from feed to milk and from milk to curd and whey in dairy sheep fed artificially contaminated concentrates.  

PubMed

An experiment was carried out using dairy ewes to study the transfer of aflatoxin B1 (AFB1) from feed to milk and from milk to cheese. The effects of AFB1 on liver function and hematological parameters were also investigated. Fifteen ewes were assigned to treatments in replicated 3 x 3 Latin squares. The experimental groups received 32, 64, or 128 microg/d of pure AFB1 for 7 d followed by 5 d of clearance. On the sixth day of the first period, the total daily milk produced by each ewe was collected separately and processed into cheese. The results indicate that the level of AFB1 used did not adversely affect animal health and milk production traits. The aflatoxin M1 (AFM1) concentrations in milk approached a steady-state condition in all treated groups between 2 and 7 d after the start of treatment. The mean AFM1 concentrations of treated groups in steady-state condition (184.4, 324.7, and 596.9 ng/kg in ewes fed 32, 64, or 128 microg of AFB1, respectively) were significantly affected by the AFB1 doses. The AFM1 concentration was linearly related to the AFB1 intake/kg of BW. The carry-over values of AFB1 from feed into AFM1 in milk (0.26 to 0.33%) were not influenced by the AFB1 doses. The AFM1 concentrations in curd and whey were linearly related to the AFM1 concentrations in the unprocessed milk. PMID:16107394

Battacone, G; Nudda, A; Palomba, M; Pascale, M; Nicolussi, P; Pulina, G

2005-09-01

76

Effects of Protein Level and Mangosteen Peel Pellets (Mago-pel) in Concentrate Diets on Rumen Fermentation and Milk Production in Lactating Dairy Crossbreds  

PubMed Central

Four, lactating dairy crossbreds (50%×50% Holstein Friesian×Native Zebu cattle) were randomly assigned according to a 2×2 factorial arrangement (two protein levels and two levels of mangosteen peel pellets (Mago-pel)) in a 4×4 Latin square design to receive four dietary treatments. All cows received concentrate at a proportion of 1 kg concentrate per 2 kg of milk yield, and urea-treated 5% rice straw (UTRS) was given ad libitum. It was found that total dry matter intakes, nutrient digestibility, ruminal pH and NH3-N concentrations were not affected (p>0.05) by treatments. Concentrations of ruminal pH and NH3-N were not affected by dietary treatments although the concentration of BUN varied significantly (p<0.05) between protein levels (p<0.05). The populations of rumen bacteria and fungal zoospores did not differ among treatments (p>0.05); however, the population of protozoa was decreased (p<0.05) when cows received Mago-pel supplementation. The composition of the population of bacteria, identified by real-time PCR technique, including total bacteria, methanogens, Fibrobacter succinogenes and Ruminococcus albus was similar (p>0.05) among dietary treatments (p>0.05); however, copy numbers of Ruminococcus flavefaciens was increased when protein level increased (p<0.05). Microbial protein synthesis, in terms of both quantity and efficiency, was enriched by Mago-pel supplementation. Milk yield was greatest in cows fed UTRS based diets with concentrate containing protein at 16% CP with Mago-pel, but were lowest without Mago-pel (p<0.05). In addition, protein level and supplementation of Mago-pel did not affect (p>0.05) milk composition except solids-not-fat which was higher in cows fed the diet with 19% CP. Therefore, feeding a concentrate containing 16% CP together with 300 g/hd/d Mago-pel supplementation results in changes in rumen fermentation and microbial population and improvements in milk production in lactating dairy crossbreds fed on UTRS. PMID:25049652

Norrapoke, T.; Wanapat, M.; Wanapat, S.

2012-01-01

77

Effects of Protein Level and Mangosteen Peel Pellets (Mago-pel) in Concentrate Diets on Rumen Fermentation and Milk Production in Lactating Dairy Crossbreds.  

PubMed

Four, lactating dairy crossbreds (50%×50% Holstein Friesian×Native Zebu cattle) were randomly assigned according to a 2×2 factorial arrangement (two protein levels and two levels of mangosteen peel pellets (Mago-pel)) in a 4×4 Latin square design to receive four dietary treatments. All cows received concentrate at a proportion of 1 kg concentrate per 2 kg of milk yield, and urea-treated 5% rice straw (UTRS) was given ad libitum. It was found that total dry matter intakes, nutrient digestibility, ruminal pH and NH3-N concentrations were not affected (p>0.05) by treatments. Concentrations of ruminal pH and NH3-N were not affected by dietary treatments although the concentration of BUN varied significantly (p<0.05) between protein levels (p<0.05). The populations of rumen bacteria and fungal zoospores did not differ among treatments (p>0.05); however, the population of protozoa was decreased (p<0.05) when cows received Mago-pel supplementation. The composition of the population of bacteria, identified by real-time PCR technique, including total bacteria, methanogens, Fibrobacter succinogenes and Ruminococcus albus was similar (p>0.05) among dietary treatments (p>0.05); however, copy numbers of Ruminococcus flavefaciens was increased when protein level increased (p<0.05). Microbial protein synthesis, in terms of both quantity and efficiency, was enriched by Mago-pel supplementation. Milk yield was greatest in cows fed UTRS based diets with concentrate containing protein at 16% CP with Mago-pel, but were lowest without Mago-pel (p<0.05). In addition, protein level and supplementation of Mago-pel did not affect (p>0.05) milk composition except solids-not-fat which was higher in cows fed the diet with 19% CP. Therefore, feeding a concentrate containing 16% CP together with 300 g/hd/d Mago-pel supplementation results in changes in rumen fermentation and microbial population and improvements in milk production in lactating dairy crossbreds fed on UTRS. PMID:25049652

Norrapoke, T; Wanapat, M; Wanapat, S

2012-07-01

78

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. PMID:23241426

2012-01-01

79

Effects of abomasal infusion of conjugated linoleic acid on milk fat concentration and yield from pasture-fed dairy cows.  

PubMed

The aim of this study was to investigate the effects of conjugated linoleic acid supplementation on the synthesis of milk fat in pasture-fed Friesian cows. In four cows, a commercial mixture containing 62.3% (wt/vol) conjugated linoleic acid was infused intraabomasally to avoid rumen fermentation and biohydrogenation. The design was a 4 x 4 Latin square in which each cow received infusions of 0, 20, 40, and 80 g/d of conjugated linoleic acid mixture for 4 d. Cows were fed freshly cut ryegrass/white clover pasture ad libitum. Milk fat concentration was decreased by 36, 43, and 62% and milk fat yield was decreased by 32, 36, and 60% by the 20, 40, and 80 g of conjugated linoleic acid/d treatments. Dry matter intake, milk protein concentration, and protein yield were unaffected by treatments; however, milk yield was increased by 11% during the 40-g conjugated linoleic acid/d treatment. The effects of conjugated linoleic acid infusion were most pronounced in reducing de novo fatty acid synthesis and desaturation. Results show that the inhibitory effect of this conjugated linoleic acid mixture on milk fat synthesis occurs in pasture-fed cows, and demonstrate the potential to dramatically alter gross milk composition. This technology could offer a management tool to manipulate milk composition and energy demands of pasture-fed cows. PMID:12647970

Mackle, T R; Kay, J K; Auldist, M J; McGibbon, A K H; Philpott, B A; Baumgard, L H; Bauman, D E

2003-02-01

80

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. PMID:8806375

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

1996-01-01

81

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

2007-01-01

82

Growth and plasma amino acid concentrations in term infants fed either whey-predominant formula or human milk.  

PubMed

We found no significant differences in mean growth measurements or mean plasma amino acid concentrations in 14 healthy full-term infants fed a whey-predominant cow milk formula and 15 healthy full-term infants who were breast-fed. Plasma taurine concentrations did not differ despite a tenfold higher level of taurine in human milk versus that in the formula. Plasma amino acid concentrations were measured one hour after feeding when the infants were 3 days and 2, 8, and 16 weeks of age. Weight, length, head circumference, crown-rump length, and skinfold thickness were measured at 3 days, 2 weeks, and 1, 2, 4, and 6 months of age. This study indicates that a whey-predominant cow milk formula compares favorably with human milk as a primary feeding for full-term infants. PMID:6600277

Volz, V R; Book, L S; Churella, H R

1983-01-01

83

Influence of weather conditions on milk production and rectal temperature of Holsteins fed two levels of concentrate  

NASA Astrophysics Data System (ADS)

Twelve lactating Holstein cows in 2nd lactation were allocated randomly, six each, to two feeding treatments: high concentrate (1 kg dairy concentrate to 2 kg milk produced) and low concentrate (1 kg dairy concentrate to 4 kg milk produced) from 7 to 106 days postcalving. Forage and water were provided adalibitum. Milk and butter fat yields and rectal temperatures were examined in relation to 9 weather variables (minimum, maximum and mean temperatures, relative humidity, temperature-humidity index (THI), radiation, wind velocity and mean temperature of the previous day). Averages for milk yield, fat yield and rectal temperature were respectively 20.4 kg, 0.7 kg and 38.9°C for the high concentrate treatment and 18.4 kg, 0.6 kg and 38.6°C for the low concentrate treatment. Weather conditions accounted for 5.6%, 0.8% and 10.8% of the day to day variation in milk yield, fat yield and rectal remperature, respectively, for the high concentrate group and 29.4%, 9.7% and 0.6%, respectively, for the low concentrate group. Only measures of ambient temperature, especially mean temperature, were closely associated with these traits.

Kabuga, J. D.; Sarpong, K.

1991-12-01

84

Effect of feeding linseed oil in diets differing in forage to concentrate ratio: 2. Milk lactone profile.  

PubMed

Lactones are important contributors to the flavour and aroma of milk and dairy products. This study was conducted to evaluate the effects of dietary linseed oil (LO) and forage to concentrate ratio on milk lactone profile. Twenty four Holstein cows were used during a 4-week feeding trial in a randomised complete block design. Cows were fed diets containing 30% (LC) or 70% (HC) concentrate, and 0% (NLO) or 3% LO in a 2×2 factorial arrangement of treatments. Milk lactone profile was evaluated using the solid phase microextraction technique. The highest levels of ?-lactones (?-6:0, ?-8:0, ?-10:0, and ?-12:0) were found with the LC/NLO diet. These concentrations were then decreased when cows received either a high level of concentrate or supplemental LO, but these effects were not additive (interaction of LO by concentrate, P<0·01). An interaction of LO by concentrate (P<0·01) was also noted on milk ?-12:0 for which the highest concentration was observed when supplementing LO in HC diet, while no effect was apparent when LO was added in LC diet. Moreover, feeding HC increased the level of ?-12:1 in milk as compared with LC, while LO had no effect on this ?-lactone. Finally, ?-12:2 was not detected in any of the milk samples studied. Organoleptic properties of milk were evaluated in a triangle test showing that a significant number of assessors perceived a difference between milk from cows fed LC/NLO as compared with milk from cows fed HC/LO. The sensory evaluation was completed by a ranking test where the intensities of fresh lactic, foreign and global flavours were not different between treatments. In conclusion, feeding LO in HC diet modified milk lactone profile with a shift toward more ?- and less ?-lactones as compared with LC diet not supplemented with LO. A difference was perceived in a triangle test between milk from these two treatments, but the sensory attributes responsible for this difference have not been identified in the current trial. PMID:24382054

Saliba, Leacady; Gervais, Rachel; Lebeuf, Yolaine; Vuillemard, Jean-Christophe; Fortin, Jacinthe; Chouinard, P Yvan

2014-02-01

85

Lead and cadmium concentrations in goat, cow, sheep, and buffalo milks from different regions of Iran.  

PubMed

In total, 137 goat, cow, sheep, and buffalo milk samples were collected in different regions of Iran and analysed to determine concentrations of lead and cadmium by a graphite furnace atomic absorption spectrometric method. The mean recovery of the analytical method was 96.3% and 104% for cadmium and lead, respectively. The mean lead and cadmium contents obtained from 137 samples were 1.93 ± 1.48 (range: 0.18-6.11 ng/ml) and 9.51 ± 4.93 ng/ml (range: 1.84 ng/ml-30.50 ng/ml), respectively. Lead concentration in 8.1% of sheep and 1.9% of cow milk samples was higher than the newly established Codex standard. The mean concentrations of cadmium and lead in animals aged ? 3 years (n=80; 1.40 ± 1.05 ng/ml and 7.91 ± 3.60 ng/ml, respectively) were lower than in animals aged >3 years (n=58; 2.69 ± 1.67 ng/ml and 11.8 ± 5.71 ng/ml, respectively). PMID:23122075

Rahimi, Ebrahim

2013-01-15

86

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

1984-01-01

87

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

PubMed

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

2013-02-01

88

Comparison of functional properties of 34% and 80% whey protein and milk serum protein concentrates.  

PubMed

This study compared the functional properties of serum protein concentrate (SPC) with whey protein concentrate (WPC) made from the same milk and with commercial WPC. The experimental SPC and WPC were produced at 34% or 80% protein from the same lot of milk. Protein contents of WPC and SPC were comparable; however, fat content was much lower in SPC compared with WPC and commercial WPC. The effect of drying methods (freeze vs. spray drying) was studied for 34% WPC and SPC. Few differences due to drying method were found in turbidity and gelation; however, drying method made a large difference in foam formation for WPC but not SPC. Between pH 3 and 7, SPC was found to have lower turbidity than WPC; however, protein solubility was similar between SPC and WPC. Foaming and gelation properties of SPC were better than those of WPC. Differences in functional properties may be explained by differences in composition and extent of denaturation or aggregation. PMID:23871371

Luck, P J; Vardhanabhuti, B; Yong, Y H; Laundon, T; Barbano, D M; Foegeding, E A

2013-09-01

89

Analysis of the Impact of European Union and United States Dairy Policies on EU-U.S. Trade in Milk Protein Concentrate.  

National Technical Information Service (NTIS)

During 1996-2000, U.S. imports of milk protein concentrate (MPC) increased rapidly. At thesame time, Commodity Credit Corporation (CCC) stocks of non-fat dry milk (NFDM) went from nothing tomore than 500 million pounds. Consequently, U.S. milk producers a...

B. C. Gehrke, J. R. Coleman, R. A. Babula

2004-01-01

90

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

PubMed

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

2013-03-01

91

Comparison of breast milk vitamin A concentration measured in fresh milk by a rapid field assay (the iCheck FLUORO) with standard measurement of stored milk by HPLC.  

PubMed

Availability of rapid, point-of-contact analytical methods would facilitate the use of breast milk vitamin A concentration (BMVA) to assess vitamin A (VA) status. We compared BMVA concentrations measured by high-performance liquid chromatography (HPLC) (the standard technique) with those by iCheck FLUORO, a new portable fluorometer that can rapidly quantify BMVA. Casual breast milk samples (n=154) were collected during a representative survey in Yaoundé and Douala, Cameroon. Milk fat and BMVA concentrations (by iCheck) were measured in fresh milk in the field. After storage at <-20?°C, BMVA concentrations were also measured by HPLC. BMVA values from the two methods were highly correlated (R(2)=0.72 for BMVA/l; R(2)=0.62 for BMVA/g fat, both P<0.0001). HPLC values were greater than iCheck values on average, and the difference increased with increasing BMVA. The iCheck FLUORO could be useful for monitoring fortification programs, but before-after surveys to assess change in BMVA concentrations should use one method consistently. PMID:24736678

Engle-Stone, R; Haskell, M J; La Frano, M R; Ndjebayi, A O; Nankap, M; Brown, K H

2014-08-01

92

Lutein supplementation increases breast milk and plasma lutein concentrations in lactating women and infant plasma concentrations but does not affect other carotenoids.  

PubMed

Lutein is a carotenoid that varies in breast milk depending on maternal intake. Data are lacking with regard to the effect of dietary lutein supplementation on breast milk lutein concentration during lactation and subsequent plasma lutein concentration in breast-fed infants. This study was conducted to determine the impact of lutein supplementation in the breast milk and plasma of lactating women and in the plasma of breast-fed infants 2-3 mo postpartum. Lutein is the dominant carotenoid in the infant brain and the major carotenoid found in the retina of the eye. Eighty-nine lactating women 4-6 wk postpartum were randomly assigned to be administered either 0 mg/d of lutein (placebo), 6 mg/d of lutein (low-dose), or 12 mg/d of lutein (high-dose). The supplements were consumed for 6 wk while mothers followed their usual diets. Breast milk carotenoids were measured weekly by HPLC, and maternal plasma carotenoid concentrations were measured at the beginning and end of the study. Infant plasma carotenoid concentrations were assessed at the end of the study. No significant differences were found between dietary lutein + zeaxanthin intake and carotenoid concentrations in breast milk and plasma or body mass index at baseline. Total lutein + zeaxanthin concentrations were greater in the low- and high-dose-supplemented groups than in the placebo group in breast milk (140% and 250%, respectively; P < 0.0001), maternal plasma (170% and 250%, respectively; P < 0.0001), and infant plasma (180% and 330%, respectively; P < 0.05). Lutein supplementation did not affect other carotenoids in lactating women or their infants. Lactating women are highly responsive to lutein supplementation, which affects plasma lutein concentrations in the infant. This trial was registered at clinicaltrials.gov as NCT01747668. PMID:24899160

Sherry, Christina L; Oliver, Jeffery S; Renzi, Lisa M; Marriage, Barbara J

2014-08-01

93

Effect of forage:concentrate ratio on the quality of ewe's milk, especially on milk fat globules characteristics and fatty acids composition.  

PubMed

The aim of this study was to evaluate the milk quality of Massese ewes receiving diets with different forage:concentrate ratios (FC ratio), specially on milk fat globules characteristics and fatty acids composition. The diet is one of the main environmental factors that influence the lipidic content of milk. A trial was carried out on twenty ewes, which had been subdivided into two homogeneous groups and kept indoors at 25 days post partum. The experiment lasted 60 days, from 40 to 100 days post partum and the animals were fed two diets that differed in terms of the FC ratio: 60:40 and 40:60, as fed. The results obtained in this study showed that a greater proportion of forage, compared with an higher percentage of concentrate, led to an increase in the percentage of fat (+8.66%) and to a decrease in the percentage of milk fat globules with a size between 2 and 5 microm (-17.32%). However, the average diameter was not affected. There was also a decrease in the percentages of some medium chain fatty acids (C12:0, C14:0; -14.89% and -4.03 respectively) and an increase in mono and polyunsaturated ones such as trans11-C18:1 (+31.71%), total CLA (+22%), EPA (+18.18%) and DHA (+66.67%). In conclusion, a greater proportion of forage seem to improve the milk fatty acid profile by the increase of some fatty acid identified has being beneficial for human health. PMID:20196898

Martini, Mina; Liponi, Gian Battista; Salari, Federica

2010-05-01

94

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.

1988-04-01

95

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))

1988-05-01

96

[Problems with feeding concentrated milk by-products to veal calves].  

PubMed

In Switzerland between 35,000 and 50,000 farm calves per year are fed rations containing concentrated whey. If the ration is balanced, whey has no adverse effects on health and growth rates of calves. Feeding whey to farm animals makes ecological and economical sense and constitutes a sound management for the disposal of milk by-products. The described case consisted of 53 calves of which 7 (13.2%) died within the feedlot-period. Based on clinical and management findings, salt-intoxication was diagnosed because of deprivation of free access to water. When large amounts of hypertonic feed containing low quality whey are fed to calves, their health is adversely affected. Therefore, article 16 of the Swiss Animal Protection Regulation should be changed. PMID:12951906

Regi, G; Morel-Egger, I; Huber, H U; Meisser, A; Wanner, M; Hässig, M

2003-08-01

97

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

PubMed Central

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

2013-01-01

98

Rapeseed glucosinolates and iodine in sows affect the milk iodine concentration and the iodine status of piglets.  

PubMed

I in the chain sow diet --> blood serum of sow --> sow milk --> piglet serum was investigated in two experiments with a total of eighty-one sows and their piglets. In experiments conducted during the last trimester of gravidity and the 28 d of lactation, diets with glucosinolates (1.9 mmol/kg diet via 100 g ground rapeseed/kg diet (Expt 1) and 2.1 and 4.2 mmol/kg diet via 75 and 150 g rapeseed press cake/kg diet (Expt 2)) were compared with control groups without rapeseed products. From 0 to 600 microg I/kg was added to sow diets during lactation. Diets without supplementary I decreased the I concentration particularly in milk and piglet serum. The presence of rapeseed and rapeseed press cake were indicated by a thiocyanate concentration increase, mainly in sow serum. The diets with glucosinolates decreased the milk and piglet serum I concentration. Spot urine and faeces samples from sows eating the rapeseed-press cake diets had increased I concentration. The sows' serum I and thyroxine did not respond to glucosinolates (Expt 1) or these diets caused an increase in concentration (Expt 2). Both these criteria seem unsuitable for the diagnosis of I status of adult animals. Glucosinolates and their degradation compounds may affect the thyroid and the mammary glands resulting in lower I milk transfer and higher renal and intestinal I excretion. PMID:11430770

Schöne, F; Leiterer, M; Hartung, H; Jahreis, G; Tischendorf, F

2001-06-01

99

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

PubMed

This work was conducted to investigate the effect of supplementing grazing ewes on pasture with a cereal concentrate on the milk fatty acid (FA) profile. Ninety Assaf ewes in mid lactation were distributed in 9 lots of 10 animals each and allocated to 3 feeding regimens: 1) pasture--ewes were only allowed to graze pasture (an irrigated sward of Lolium perenne, Trifolium pratense, and Dactylis glomerata); 2) PS--grazing ewes were supplemented with oat grain (700 g/animal and day); and 3) TMR--ewes were fed ad libitum a total mixed ration (TMR; 80:20 concentrate/forage ratio). Milk yield and composition were recorded for 5 wk. The highest milk yield was observed in ewes receiving the TMR and the lowest in grazing ewes supplemented with oat grain. Productions of milk fat, protein, and total solids showed the lowest values in treatment PS. The atherogenicity index, which comprises C12:0, C14:0, and C16:0, in PS milk fat was no different from that observed in milk from animals on pasture (1.53 for pasture, 1.54 for PS, and 3.22 for TMR). Oat grain supplementation generated higher amounts of C18:0 and cis-9 C18:1 in milk fat than the pasture-only diet, but significantly decreased the levels of alpha-linolenic acid and most of intermediates of the process of biohydrogenation of this FA. Cis-9 trans-11 C18:2 and trans-11 C18:1, its precursor for endogenous synthesis in the mammary gland, were lower in PS (0.58 and 1.59 g/100 g of total FA) than in TMR (0.72 and 1.92 g/100 g of total FA) and very different from the results observed in grazing ewes receiving no supplement (1.21 and 3.88 g/100 g of total FA). Furthermore, the lowest levels of trans-10 C18:1 and trans-10 cis-12 C18:2 were detected in the milk fat of ewes fed pasture. It is concluded that, when pasture quality and availability do not limit dairy production, supplementation of grazing ewes with oat grain compromised the milk FA profile without any significant positive effect on milk production. PMID:19620680

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

2009-08-01

100

Urea and amphibian water economy.  

PubMed

Accumulation of urea in the body fluids enables some amphibians to tolerate high ambient salinities (Bufo viridis, Xenopus laevis, Rana cancrivora, Ambystoma tigrinum, Batrachoseps spp.) or to estivate in soil with low water potentials (Scaphiopus spp.). These species are assumed not only to accumulate urea produced in the normal metabolism, but to synthesize urea in response to water shortage. Re-examination of the data did not support the view of an osmoregulatory urea synthesis. Increased urea synthesis on exposure to high salinities in X. laevis, R. cancrivora and Batrachoseps spp. seemed to reflect reactions to an adverse environment. It is suggested that in amphibians, solute concentration in the plasma and rate of excretion of urea are coordinated so that at a certain plasma concentration, urea is excreted at the same rate at which it is produced. The higher the level of urea in the body fluids at balance between production and excretion, the higher the tolerance of the species of low external water potentials. The mechanisms that integrate the relationship between plasma solute concentration and handling of urea by the kidneys are not known. PMID:9172374

Jørgensen, C B

1997-06-01

101

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...

102

Correlations between periparturient serum concentrations of non-esterified fatty acids, beta-hydroxybutyric acid, bilirubin, and urea and the occurrence of clinical and subclinical postpartum bovine endometritis  

PubMed Central

Background Postpartum endometritis in cattle is a multifactorial disease with high economic impact. Both, clinical endometritis (CE) and subclinical endometritis (SCE) result in decreased reproductive performance. Results from in vitro studies led to the implication that non-esterified fatty acids (NEFA), beta-hydroxybutyric acid (BHBA), bilirubin, and urea could be used as predictors for endometritis in veterinary practice. In this field study, we set out to establish optimal predictor cut points of these metabolic parameters for the detection of CE and SCE. Serum samples were collected one week prior to parturition (wk -1), in the first week postpartum (wk +1) and between 28 and 35 days postpartum (wk +5) from 209 Holstein-Friesian cows. At wk +5, all cows were examined for signs of CE and SCE. Results Higher concentrations of urea at wk +1 were associated with increased odds of CE (OR = 1.7, P = 0.04) in primiparous (PP) cows. A predictor cut point of 3.9 mmol/L (sensitivity: 61%, specificity: 70%) was determined. In multiparous (MP) cows, the logistic regression model revealed that higher concentrations of NEFA at wk -1 were associated with increased odds of CE and SCE (healthy vs. CE: OR = 9.1, P = 0.05; healthy vs. SCE: OR = 12.1, P = 0.04). A predictor cut point of 0.3 mmol/L (sensitivity: 38%, specificity: 87% and sensitivity: 35%, specificity: 89%, respectively) was determined. Increasing concentrations of urea at wk +5 were associated with decreased odds of CE (healthy vs. CE: OR = 0.6, P = 0.01; SCE vs. CE: OR = 0.5, P = 0.03). A predictor cut point of 3.8 mmol/L (sensitivity: 52%, specificity: 81%) was determined. For BHBA and bilirubin relationships with CE or SCE were not detected. Conclusions The corresponding combinations of sensitivity and specificity of the determined predictor cut points were not satisfactory for practical use. Thus, the analysed parameters, i.e. NEFA, BHBA, bilirubin, and urea, at the chosen time points, i.e. at wk -1, at wk +1, and at wk +5 relative to calving, are unsatisfactory for disease prediction. Further research is required to clarify the questions raised by the current study. PMID:20979598

2010-01-01

103

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

2002-01-01

104

Characterization of the purified actinidin as a plant coagulant of bovine milk  

Microsoft Academic Search

In this work, actinidin was characterized in view of its possible suitability as a coagulant enzyme in the manufacturing process\\u000a of cheese. The results show that actinidin does exhibit milk-clotting activity, which is correlated with the enzyme concentrations.\\u000a The combined use of urea and SDS–PAGE led to the conclusion that the milk clot is clearly separated from the whey proteins

Angela Roberta Lo Piero; Ivana Puglisi; Goffredo Petrone

105

Kinetics of heat-induced whey protein denaturation and aggregation in skim milks with adjusted whey protein concentration.  

PubMed

Microfiltration and ultrafiltration were used to manufacture skim milks with an increased or reduced concentration of whey proteins, while keeping the casein and milk salts concentrations constant. The skim milks were heated on a pilot-scale UHT plant at 80, 90 and 120 degrees C. The heat-induced denaturation and aggregation of beta-lactoglobulin (beta-lg), alpha-lactalbumin (alpha-la) and bovine serum albumin (BSA) were quantified by polyacrylamide gel electrophoresis. Apparent rate constants and reaction orders were calculated for beta-lg, alpha-la and BSA denaturation. Rates of beta-lg, alpha-la and BSA denaturation increased with increasing whey protein concentration. The rate of alpha-la and BSA denaturation was affected to a greater extent than beta-lg by the change in whey protein concentration. After heating at 120 degrees C for 160 s, the concentration of beta-lg and alpha-la associated with the casein micelles increased as the initial concentration of whey proteins increased. PMID:16174369

Oldfield, David J; Singh, Harjinder; Taylor, Mike W

2005-08-01

106

The daily rhythm of milk synthesis is dependent on the timing of feed intake in dairy cows  

PubMed Central

Abstract Regulation of the daily rhythm of milk synthesis is important to production animals and breastfeeding, but is difficult to observe in nursing animals. The rate of food intake varies over the day and is expected to create a daily rhythm of nutrient absorption. The objective of this study was to determine if the timing of food intake entrains a daily pattern of milk synthesis. Seventeen Holstein cows were used in a crossover design. Treatments were ad libitum feeding of a total mixed ration once daily (1× fed) or fed in four equal meals every 6 h (4× fed). Cows were milked every 6 h the last 7 days of each period. There was a treatment by time of day interaction for milk and milk component yield and concentration. Milk fat and protein concentration and yield exhibited a daily rhythm and the amplitude of the rhythm was reduced in 4× fed. In addition, milk fat percent was higher in 4× fed than 1× fed at three of the four milking intervals (0.22–0.45% higher) and 4× fed increased daily milk fat yield. Treatment by time of day interactions were detected for plasma glucose, insulin, and blood urea nitrogen. These variables also fit a cosine function with a 24 h period and the amplitudes of plasma glucose, insulin, and blood urea nitrogen rhythms were decreased by 4× feeding. In conclusion, there is a circadian pattern of milk synthesis in the dairy cow that is responsive to the timing of food intake. PMID:24963033

Rottman, L. Whitney; Ying, Yun; Zhou, Kan; Bartell, Paul A.; Harvatine, Kevin J.

2014-01-01

107

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

PubMed

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

2013-10-01

108

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...

109

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

Hélène Jacques; Nadine Leblanc; Nathalie Bergeron

110

Maternal Milk Concentration of Zinc, Iron, Selenium, and Iodine and Its Relationship to Dietary Intakes  

Microsoft Academic Search

The dietary intake of zinc (Zn), iron (Fe), selenium (Se), and iodine (I) of 31 lactating Mexican–American women attending\\u000a the Hidalgo County WIC program in Rio Grande Valley (RGV), Texas was estimated from 24-h dietary recall interviews. Milk samples\\u000a were obtained from lactating mothers who had infants 3 months of age and younger. Milk samples were collected in two visits\\u000a to

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

2009-01-01

111

Isoflavone concentration of soybean meal from various origins and transfer of isoflavones into milk of dairy cows  

Microsoft Academic Search

The objective of this study was to determine the isoflavone concentration of defatted soybean meals from Argentina, Brazil\\u000a and USA. Moreover, the transfer of isoflavones from soybean meal into the milk of dairy cows was investigated in a preliminary\\u000a dose–response study. Six samples of soybean meal from each origin imported into the EU were taken at European harbours and\\u000a subsequently

Gerhard Flachowsky; Martin Hünerberg; Ulrich Meyer; Dietmar R. Kammerer; Reinhold Carle; Miriam Goerke; Meike Eklund

112

Predicting PCB concentrations in cow milk: validation of a fugacity model in high-mountain pasture conditions.  

PubMed

A fugacity model reported in the literature was applied to a high-altitude pasture in the Italian Alps. The model takes into account three compartments (digestive tract, blood and fat tissues) in unsteady-state conditions using food as the contamination source. Disregarding biotransformation inside cow tissues, the predicted concentrations of 14 polychlorinated biphenyls (PCBs) in milk were in good agreement with the observed data, especially for congeners known for their resistance to biotransformation (e.g., CB-138 and 153). In contrast, the predicted concentrations were clearly overestimated for congeners with high biotransformation susceptibilities. Therefore data measured in milk and faeces were used to calculate the first-order-biotransformation rate constants in dairy cows. The PCB absorption efficiency observed for pasture conditions was lower than that observed in the cowshed. The final version of the model included biotransformation and observed PCB absorption and was able to predict PCB concentrations in cow milk with mean differences between the predicted and measured data below ± 20% for most congeners. PMID:24802270

Tremolada, Paolo; Guazzoni, Niccolò; Parolini, Marco; Rossaro, Bruno; Bignazzi, Marta Maria; Binelli, Andrea

2014-07-15

113

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)] [State Univ. of New York, Buffalo, NY (United States)

1999-02-01

114

Phytotoxicity of foliar-applied urea  

PubMed Central

Recent work in our laboratory showed that the adverse effect of urea fertilizer on seed germination and seedling growth in soil is due to ammonia produced through hydrolysis of urea by soil urease (NH2CONH2 + H2O ? 2NH3 + CO2) and can be eliminated by amending the fertilizer with a small amount of a urease inhibitor such as phenylphosphorodiamidate. Because the leaf-tip necrosis often observed after foliar fertilization of plants with urea is usually attributed to ammonia formed through hydrolysis of urea by plant urease, we studied the possibility that this necrosis could be eliminated or reduced by adding phenylphosphorodiamidate to the urea fertilizer. We found that, although addition of this urease inhibitor to foliar-applied urea increased the urea content and decreased the ammonia content and urease activity of soybean [Glycine max. (L.) Merr.] leaves fertilized with urea, it increased the leaf-tip necrosis observed after fertilization. We conclude that this necrosis resulted from accumulation of toxic amounts of urea rather than from formation of toxic amounts of ammonia. This conclusion was supported by our finding that the necrotic areas of soybean leaves treated with urea or with urea and phenylphosphorodiamidate contained much higher concentrations of urea than did the nonnecrotic areas. Images PMID:16594077

Krogmeier, Michael J.; McCarty, Gregory W.; Bremner, John M.

1989-01-01

115

A comparison of the concentrations of energy-balance-related variables in jugular and mammary vein blood of dairy cows with different milk yield.  

PubMed

The aim of this study was to compare the concentrations of blood variables obtained simultaneously from the jugular and mammary veins of dairy cows. Eighty Holstein cows were divided into four equal groups: dry, low- (LY), medium- (MY) and high-yielding (HY). Blood insulin, glucose, non-esterified fatty acid (NEFA), beta-hydroxybutyrate (BHBA) and urea concentrations were measured. The jugular and mammary vein (J/M) ratio between concentrations of each variable was calculated. Differences between the groups of cows in concentrations of variables in the jugular vein were not in accordance with those obtained for the mammary vein. J/M values for insulin and glucose concentrations were above 1.0 in all groups of cows. The ratios for NEFA and BHBA concentrations were under or equal to 1.0 in dry and LY cows but above 1.0 in the MY and HY groups, indicating that in MY and HY cows those metabolites are apparently utilised by the mammary gland. J/M values for urea were above 1.0 in dry and LY cows but less than 1.0 in groups MY and HY, indicating that in the latter case urea is apparently released by the mammary gland. In conclusion, J/M for NEFA, BHBA and urea may be useful for estimation of the critical point when the mammary gland receives insufficient energy precursors for its current activity. PMID:24334081

Samanc, Horea; Kirovski, Danijela; Laki?, Nada; Celeska, Irena; Bojkovi?-Kova?evi?, Slavica; Sladojevi?, Zeljko; Ivanov, Ivan

2014-03-01

116

Rumen fermentation and performance of lactating dairy cows affected by physical forms and urea treatment of rice straw.  

PubMed

The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW) of 409±20 kg were randomly assigned according to a 4×4 Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS), urea-treated (5%), long form rice straw (5% ULRS), urea-treated (2.5%), long form rice straw (2.5% ULRS) and urea-treated (2.5%), chopped (4 cm) rice straw (2.5% UCRS). Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p<0.05). Ruminal pH was not altered among all treatments (p>0.05), whereas ruminal NH3-N, BUN and MUN were found to be increased (p<0.01) by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs) concentrations especially those of acetic acid were decreased (p<0.05) and those of propionic acid were increased (p<0.05), thus acetic acid:propionic acid was subsequently lowered (p<0.05) in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05), while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01). From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows. PMID:25049912

Gunun, P; Wanapat, M; Anantasook, N

2013-09-01

117

Effects of milk feeding, frequency and concentration on weaning and buffalo (Bubalus bubalis) calf growth, health and behaviour.  

PubMed

Growth, weight at birth and daily weight gain (DWG) on 12 water buffalo calves, starting from 6 days of age until completion of weaning, was investigated in this study. Different feeding regimens were given to two groups of animals with regard to daily milk replacer: (1) group 1 (G1) received a double concentration in single administration; whereas (2) group 2 (G2) received the same amount of milk replacer split twice daily. Blood samples were collected from each calf on days 6, 30, 60 and 90 to evaluate acute phase proteins (haptoglobin), bactericide activity, lysozime, total protein content and biochemical parameters. No differences were observed between the two groups in terms of dry matter intake, feed efficiency and live body weight at the end of the study. Interestingly, a significantly (P?milk replacer in water buffalo calf during weaning. This new approach facilitates calves management, without interfering with calves growing performances. PMID:23712396

Vecchio, Domenico; Di Palo, Rossella; De Carlo, Esterina; Esposito, Luigi; Presicce, Giorgio Antonio; Martucciello, Alessandra; Chiosi, Emilio; Rossi, Pasquale; Neglia, Gianluca; Campanile, Giuseppe

2013-11-01

118

Effects of recombinant bovine somatotropin implants on serum concentrations of somatotropin, insulin-like growth factor-I and blood urea nitrogen in steers.  

PubMed

Four cross-bred beef steers averaging 346 kg were used in a 4 x 4 Latin square design to determine the effect of prolonged-release recombinant bovine somatotropin (rbGH) implants on serum concentrations of somatotropin (GH), insulin-like growth factor-I (IGF-I) and blood urea nitrogen (BUN). Recombinant bGH implants of 0, 40, 80 or 160 mg were administered subcutaneously in the tailhead during the 4 trial periods. Each steer received each treatment starting at 06:00 on day 0 with 21 days between treatments. Jugular vein blood samples were collected on days 0, 1, 2 and 3 (4 day time course for GH, IGF-I and BUN) and every 15 min (GH profile) for 6 h on day 3. Serum baseline GH values were higher (P < 0.10) for the 80 and 160 mg treatments than for the control, and peak amplitude was decreased (P < 0.05) by the 40 and 160 mg treatments. There was a trend (P < 0.11) for fewer GH peaks during the 160 mg treatment. Somatotropin concentrations decreased from day 1 to day 3 (P < 0.05) in a linear manner. Serum IGF-I concentrations increased (P < 0.05) in a linear dose-dependent manner from the 0 mg to the 160 mg treatment. BUN concentrations were not significantly altered by rbGH treatment. Results from this experiment indicate that rbGH implants significantly increase serum IGF-I and GH baseline concentrations while suppressing GH peak amplitude in finishing steers. PMID:7858482

Roeder, R A; Garber, M J; Dalke, B S; Kasser, T R; Veenhuizen, J; Schelling, G T

1994-09-01

119

Short communication: ketone body concentration in milk determined by Fourier transform infrared spectroscopy: value for the detection of hyperketonemia in dairy cows.  

PubMed

The objective of this study was to evaluate Fourier transform infrared (FTIR) spectrometry to measure milk ketone bodies to detect hyperketonemic cows and compare this method with milk fat to protein ratio to detect hyperketonemia. Plasma and milk samples were obtained weekly from calving to wk 9 postpartum from 69 high-producing dairy cows. The reference test for hyperketonemia was defined as plasma concentration of beta-hydroxybutyrate (BHBA) >or=1,200 micromol/L. The weekly prevalence of hyperketonemia during the first 9 wk of lactation was, on average, 7.1%. Both BHBA and acetone in milk, determined by FTIR, had a higher sensitivity (80%) to detect hyperketonemia compared with milk fat to protein ratio (66%). Specificity was similar for the 3 diagnostic tests (71, 70, and 71%). In conclusion, FTIR predictions of BHBA or acetone in milk can detect cows with hyperketonemia in early lactation with a higher accuracy compared with the use of milk fat to protein ratio. Because of the high proportion of false-positive tests, there are concerns about the practical applicability of FTIR predictions of acetone, BHBA, and fat to protein ratio in milk to detect hyperketonemic cows. PMID:20630223

van Knegsel, A T M; van der Drift, S G A; Horneman, M; de Roos, A P W; Kemp, B; Graat, E A M

2010-07-01

120

Maternal Sodium Intake Does Not Affect Postprandial Sodium Concentrations in Human Milk  

Microsoft Academic Search

Sodium concentrationin human milk is known to varydiurnallyand throughout lactation. To investigatepotential postprandial variation, eight exclusively breast-feeding mothers of infants 10-19 wk of age were visited on two different days after a 3-h fast. On one day, they were fed a low sodium lunch (130 mg), and on the other, the same lunch with a high sodium content (2175 mg).

ROCHELLE R. EREMAN; BO LÃ-NHERDALANDKATHRYN C. DEWEY

121

Reducing Concentrate Supplementation in Dairy Cow Diets While Maintaining Milk Production with Pea-Wheat Intercrops  

Microsoft Academic Search

In the first of 2 experiments, 40 dairy cows were used to evaluate the milk production potential and concen- trate-sparing effect of feeding dairy cows a basal diet of pea-wheat intercrop silages instead of perennial rye- grass silage (GS). Dairy cows were offered GS or 2 in- tercrop silagesprepared from wheat andeither Magnus peas (MW, a tall-straw variety) or Setchey

A. T. Adesogan; M. B. Salawu; S. P. Williams; W. J. Fisher; R. J. Dewhurst

2004-01-01

122

Elevated concentrate-to-forage ratio in dairy cow rations is associated with a shift in the diameter of milk fat globules and remodeling of their membranes.  

PubMed

We examined the effects of concentrate-to-forage ratio in dairy cow rations on milk-fat composition, with a specific focus on the structure of milk fat globules (MFG). Twenty-four Holstein cows, 153 d in milk, were assigned to 2 dietary treatments in a crossover design study. Treatments were (1) high-concentrate (65%), low-forage (35%; HCLF) diet and (2) low-concentrate (35%), high-forage (65%; LCHF) diet. The mean diameter of the MFG; plasma concentrations of insulin, glucose, and nonesterified fatty acids (FA); and the composition and concentrations of milk FA and polar lipids were determined. Concentrations of insulin were 56% higher, and those of nonesterified FA 46% lower, in the HCLF than in the LCHF diet. The milk yield was 8.5 kg/d higher and yields of fat, protein, and lactose were 180, 350, and 403 g/d higher, respectively, in the HCLF versus LCHF diet. Milk FA composition differed between treatments, with 1.5 and 1.0 percentage units higher saturated and polyunsaturated FA concentrations, respectively, in the HCLF versus LCHF diet. Mean MFG diameter tended to be smaller (0.2 ?m) in the HCLF diet than in the LCHF diet, associated with increased daily phospholipids yield (34%), lower phosphatidylserine and higher phosphatidylcholine concentrations. In conclusion, the decreased milk and fat yields in the LCHF diet were associated with remodeling of the MFG membrane and with the secretion of larger MFG. Membrane remodeling of the mammary epithelium membranes seems to play a role in regulating MFG size. PMID:25087025

Argov-Argaman, Nurit; Mesilati-Stahy, Ronit; Magen, Yogev; Moallem, Uzi

2014-10-01

123

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

PubMed

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

2012-05-01

124

Urea transporter knockout mice and their renal phenotypes.  

PubMed

Urea transporter gene knockout mice have been created for the study of the urine-concentrating mechanism. The major findings in studies of the renal phenotype of these mice are as follows: (1) Urea accumulation in the inner medullary interstitium is dependent on intrarenal urea recycling mediated by urea transporters; (2) urea transporters are essential for preventing urea-induced osmotic diuresis and thus for water conservation; (3) NaCl concentration in the inner medullary interstitium is not significantly affected by the absence of IMCD, descending limb of Henle and descending vasa recta urea transporters. Studies in urea transporter knockout mouse models have highlighted the essential role of urea for producing maximally concentrated urine. PMID:25298343

Fenton, Robert A; Yang, Baoxue

2014-01-01

125

Continuous milking of dairy cows disrupts timing of peak IgG concentration appearance in mammary secretions.  

PubMed

The length of the dry period in commercial dairy production is under close scrutiny. While the main concern is the composition and volume of milk produced, the evaluation of colostrum quality under these new paradigms has suggested a decline in IgG concentrations, while some reports indicate no change. Colostrum quality has been defined as an adequate concentration (>50 mg/ml) of immunoglobulin in the secretions to provide the newborn with maximal disease resistance. We investigated the appearance of IgG in mammary pre- and post partum secretions in cows without a dry period (continuously milked, Dry0) and compared the secretions with cows that experienced a dry period of 60 d (Dry60). Blood was collected during the experimental period and plasma analysed for progesterone (P4) and prolactin (Prl). Approximately -6 d relative to parturition, the Dry0 animals exhibited increased concentration of IgG in their secretions to an average of ?35 mg/ml that remained rather constant through subsequent pregnancy and following parturition. Dry0 cows were producing an average IgG concentration in parturition colostrum of 44·2±17·6 mg/ml that was not different than that of controls (66·86±16·8 mg/ml). However, Dry0 cows exhibited high variation, different peak times (day) of IgG concentration including times that occurred both pre and post parturition. IgG mass of the Dry0 cows remained rather constant pre- and post partum and did not show the same declining mass following parturition that was shown for the Dry60 cows. The change in plasma P4 and Prl were shown to have no timing effect on colostrum IgG concentration. PMID:24955588

Baumrucker, Craig R; Zbinden, Rahel S; van Dorland, H Anette; Remmelink, Gerrit J; Kemp, Bas; van Knegsel, Ariette T M; Bruckmaier, Rupert M

2014-11-01

126

PCDD, PCDF, PCB and PBDE concentrations in breast milk of mothers residing in selected areas of Slovakia.  

PubMed

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006-2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g(-1) fat (median: 13.1 pg g(-1) fat; mean: 18.0 pg g(-1) fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g(-1) fat, with median and mean value of 0.43 ng g(-1) fat and 0.57 ng g(-1) fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations. Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg(-1)b.w., with a median value of 58.9 pg TEQ kg(-1)b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1-4 pg TEQ kg(-1)b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg(-1)b.w.d(-1), with median value of 1.7 ng kg(-1)b.w.d(-1). PMID:21474162

Chovancová, Jana; ?onka, Kamil; Ko?an, Anton; Sejáková, Zuzana Stachová

2011-05-01

127

The human milk metabolome reveals diverse oligosaccharide profiles.  

PubMed

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 clinicaltrials.gov as NCT01817127. PMID:24027187

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

2013-11-01

128

The association between local fish consumption and DDE, mirex, and HCB concentrations in the breast milk of Mohawk women at Akwesasne.  

PubMed

A study was conducted to assess the extent to which the consumption of local fish contaminated with p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE), mirex, and hexachlorobenzene (HCB) has impacted the concentrations of these compounds in the milk of nursing Mohawk women residing along the St. Lawrence River. From 1986 to 1992, 97 Mohawk women were interviewed, and each donated a one-time sample of at least 50 ml of breast milk. The comparison population consisted of 154 Caucasians from other rural areas in New York State. After adjustment for potential confounders, Mohawk mothers who gave birth from 1986 to 1990 had significantly higher geometric mean p,p'-DDE milk concentrations than did the control group, but no significant differences were observed from 1991 to 1992. In contrast, mirex was significantly elevated among the Mohawks throughout the study period, while HCB showed no difference at any point. Mohawk women with the greatest estimated cumulative lifetime exposure to p,p'-DDE from local fish consumption had a significantly higher geometric mean milk level of that compound relative to control women, but no differences in mirex or HCB concentrations in breast milk by local fish consumption were found. The reduction in breast milk p,p'-DDE concentrations among the Mohawk women from 1986 to 1990 parallels a corresponding decrease in local fish consumption, and may be the result of the advisories that have been issued over the past decade recommending against the consumption of local fish by pregnant and nursing Mohawk women. Elevations in the concentrations of mirex in the breast milk of the Mohawks are consistent with the fact that it is a common contaminant in the region and throughout the Lake Ontario-St. Lawrence River Basin. PMID:11687911

Fitzgerald, E F; Hwang, S A; Deres, D A; Bush, B; Cook, K; Worswick, P

2001-01-01

129

and retained were higher in the high compared with the low CP diets. Using the N-balance data obtained in this trial the CP requirements of a 60 kg goat, producing 1 kg milk  

E-print Network

significantly). , In blood, the fat supplement increased the concentration of urea, glucose, triglycerides obtained in this trial the CP requirements of a 60 kg goat, producing 1 kg milk of 4 p. 100 protein levels ; furthermore it increased the glucose concentration only at the low level. The fat supplement

Paris-Sud XI, Université de

130

Expression of cathelicidins mRNA in the goat mammary gland and effect of the intramammary infusion of lipopolysaccharide on milk cathelicidin-2 concentration.  

PubMed

Cathelicidins are a family of antimicrobial peptides found in neutrophils and the epithelium that have broad-spectrum activity against bacteria. This study aimed to investigative the mRNA expression of cathelicidins and protein localization of cathelicidin-2 in the goat mammary gland and its secretion into milk. The mRNA expression of cathelicidins was examined in different regions of the mammary gland by reverse transcription PCR. A cathelicidin-2 antibody was raised in rabbits by immunization with a synthetic cathelicidin-2 peptide consisting of 17 amino acids. The protein localization of cathelicidin-2 was investigated in the mammary gland by immunohistochemistry. Skim milk was collected before (0 h) and 2, 4, 8, 12, and 24h after the intramammary infusion of lipopolysaccharide and saline, and the concentration of cathelicidin-2 was examined by an enzyme immunoassay. The mRNAs of cathelicidin-1, 2, 3, 6, and 7 were expressed in both the teat and deep region of the mammary gland from healthy and mastitic goats. Immunoreactive cathelicidin-2 was not localized in the epithelial cells of the teat skin, teat cistern, or mammary alveoli, whereas it was localized in polymorphonuclear cells in the mammary gland and those collected from the blood and milk. Cathelicidin-2 was detected in skim milk by Western blotting. The concentration of cathelicidin-2 in milk increased 4h after the intramammary infusion of lipopolysaccharide. These results suggest that cathelicidin-2 is expressed in polymorphonuclear cells and is secreted into milk in goat. PMID:24572177

Zhang, Gong-Wei; Lai, Song-Jia; Yoshimura, Yukinori; Isobe, Naoki

2014-05-14

131

Mineral concentrations in diets, water, and milk and their value in estimating on-farm excretion of manure minerals in lactating dairy cows.  

PubMed

Thirty-nine commercial dairies in Merced County, California were enrolled in the present study to (1) compare lactating cow mineral intakes (via drinking water and total mixed ration) to the National Research Council (NRC) requirements, (2) evaluate the association between dietary concentrations of minerals with and without drinking water and adjusted for mineral concentrations in milk, and (3) compare 4 different methods to estimate excretion of minerals using either assays or estimations of milk mineral outputs and total daily mineral intake per cow with or without minerals coming from drinking water. Dairies were selected to represent a range of herd milk yields and a range of water mineral contents. Samples of total mixed ration, drinking water, and bulk tank milk were taken on 2 different days, 3 to 7d apart in each farm. Across-farm medians and percentile distributions were used to analyze results. The herd median milk yield interquartile ranged (10th to 90th percentile) from less than 25 to more than 39 kg/d and the concentration of total solids in water interquartile ranged from less than 200 to more than 1,490 mg/L. Including drinking water minerals in the diets increased dietary concentrations by <4% for all minerals except for Na and Cl, which increased by 9.3 and 6.5%, respectively. Concentrations of P and K in milk were essentially the same as the NRC value to estimate lactation requirements. However, NRC milk values of Ca, Cl, and Zn were 10 to 20% greater than dairy farm values; and Na, Cu, Fe, and Mn were no less than 36% below NRC values. Estimated excretion of minerals via manure varied substantially across farms. Farms in the 10th percentile did have 2 to 3 times less estimated mineral excretions than those in the 90th percentile (depending on the mineral). Although including water minerals increased excretion of most minerals, the actual median effect of Ca, Mg, S, Cu, Fe, and Mn was less than 5%, and about 8% for Na and Cl. Replacing assayed concentrations of minerals in milk with NRC constants resulted in reduced estimated excretion of Ca, Na, Cu, Fe, and Zn, but median differences were <5% except for Na which was 7.5%. Results indicate that not including mineral intake via drinking water and not using assayed concentrations of milk minerals lead to errors in estimation manure excretion of minerals (e.g., Ca, Na, Cl, and S). PMID:23477818

Castillo, A R; St-Pierre, N R; Silva del Rio, N; Weiss, W P

2013-05-01

132

The effects of low vs. high concentrate level in the diet on performance in cows milked two or three times daily in early lactation  

Microsoft Academic Search

The effect of concentrate:forage ratio in the diet and milking frequency on performance was investigated in a 2×2 factorial block design comprising 40 Danish–Holstein dairy cows from parturition to week 16 of lactation. One factor was concentrate level, either low (L: 25% concentrate) or high (H: 75% concentrate), in an ad libitum fed total mixed ration. The second factor was

J. B Andersen; N. C Friggens; K Sejrsen; M. T Sørensen; L Munksgaard; K. L Ingvartsen

2003-01-01

133

A triad of highly divergent polymeric immunoglobulin receptor (PIGR) haplotypes with major effect on IgA concentration in bovine milk.  

PubMed

The aim of this study was to determine a genetic basis for IgA concentration in milk of Bos taurus. We used a Holstein-Friesian x Jersey F2 crossbred pedigree to undertake a genome-wide search for QTL influencing IgA concentration and yield in colostrum and milk. We identified a single genome-wide significant QTL on chromosome 16, maximising at 4.8 Mbp. The polymeric immunoglobulin receptor gene (PIGR) was within the confidence interval of the QTL. In addition, mRNA expression analysis revealed a liver PIGR expression QTL mapping to the same locus as the IgA quantitative trait locus. Sequencing and subsequent genotyping of the PIGR gene revealed three divergent haplotypes that explained the variance of both the IgA QTL and the PIGR expression QTL. Genetic selection based on these markers will facilitate the production of bovine herds producing milk with higher concentrations of IgA. PMID:23536764

Berry, Sarah; Coppieters, Wouter; Davis, Stephen; Burrett, Alayna; Thomas, Natalie; Palmer, David; Kelly, Van; Obolonkin, Vladimir; Sanders, Kathryn; Spelman, Richard; Georges, Michel; Lehnert, Klaus; Snell, Russell

2013-01-01

134

Dioxin concentrations in breast milk of Vietnamese nursing mothers: a survey four decades after the herbicide spraying.  

PubMed

In an operation by United States Armed Forces during 1961 to 1971, large quantities of herbicides were sprayed in South Vietnam. These herbicides contained 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD), the most toxic congener of dioxins. Several decades after the herbicide spraying ceased, dioxin concentrations in the environment and human remained elevated in the sprayed areas. Breast milk samples from 520 nursing mothers residing in areas including the hot spots as well as the sprayed and unsprayed areas were collected to quantify the levels of dioxins. The total toxic equivalents of 2,3,7,8-substitued PCDDs/PCDFs in breast milk of mothers living in the hot spots, and the sprayed and unsprayed areas were 14.10 pg/g lipid, 10.89 pg/g lipid, and 4.09 pg/g lipid for primiparae and 11.48 pg/g lipid, 7.56 pg/g lipid, and 2.84 pg/g lipid for multiparae, respectively, with significant differences in the values among the three areas. In the hot spots, dioxin levels were highly correlated with the residency of mothers after adjustment for their age and parity. PMID:21718047

Tai, Pham The; Nishijo, Muneko; Kido, Teruhiko; Nakagawa, Hideaki; Maruzeni, Shoko; Naganuma, Rie; Anh, Nguyen Thi Nguyet; Morikawa, Yuko; Luong, Hoang Van; Anh, Tran Hai; Hung, Nguyen Ngoc; Son, Le Ke; Tawara, Kenji; Nishijo, Hisao

2011-08-01

135

Lead content of milk and infant formula  

Microsoft Academic Search

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

1980-01-01

136

Development of a Raman chemical image detection algorithm for authenticating dry milk  

NASA Astrophysics Data System (ADS)

This research developed a Raman chemical imaging method for detecting multiple adulterants in skim milk powder. Ammonium sulfate, dicyandiamide, melamine, and urea were mixed into the milk powder as chemical adulterants in the concentration range of 0.1-5.0%. A Raman imaging system using a 785-nm laser acquired hyperspectral images in the wavenumber range of 102-2538 cm-1 for a 25×25 mm2 area of each mixture. A polynomial curve-fitting method was used to correct fluorescence background in the Raman images. An image classification method was developed based on single-band fluorescence-free images at unique Raman peaks of the adulterants. Raman chemical images were created to visualize identification and distribution of the multiple adulterant particles in the milk powder. Linear relationship was found between adulterant pixel number and adulterant concentration, demonstrating the potential of the Raman chemical imaging for quantitative analysis of the adulterants in the milk powder.

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

2013-05-01

137

Extraction of urea and ammonium ion  

NASA Technical Reports Server (NTRS)

Water purification system keeps urea and ammonium ion concentration below toxic limits in recirculated water of closed loop aquatic habitat. Urea is first converted to ammonium ions and carbon dioxide by enzygmatic action. Ammonium ions are removed by ion exchange. Bioburden is controlled by filtration through 0.45 micron millipore filters.

Anselmi, R. T.; Husted, R. R.; Schulz, J. R.

1977-01-01

138

Breast milk vitamin B-12 concentrations in Guatemalan women are correlated with maternal but not infant vitamin B-12 status at 12 months postpartum.  

PubMed

In our previous studies, one-third of lactating Guatemalan women, infants, and children had deficient or marginal serum vitamin B-12 concentrations. Relationships among maternal and infant status and breast milk vitamin B-12, however, have not, to our knowledge, been investigated in such populations. Our purpose was to measure breast milk vitamin B-12 in Guatemalan women with a range of serum vitamin B-12 concentrations and explore associations between milk vitamin B-12 concentrations and maternal and infant vitamin B-12 intake and status. Participants were 183 mother-infant pairs breastfeeding at 12 mo postpartum. Exclusion criteria included mother <17 y, infant <11.5 or >12.5 mo, multiple birth, reported health problems in mother or infant, and mother pregnant >3 mo. Data collected on mothers and infants included anthropometry, serum and breast milk vitamin B-12, and dietary vitamin B-12. Serum vitamin B-12 concentrations indicated deficiency (<150 pmol/L) in 35% of mothers and 27% of infants and marginal status (150-220 pmol/L) in 35% of mothers and 17% of infants. In a multiple regression analysis, breast milk vitamin B-12 concentration was associated (P < 0.05) with both maternal vitamin B-12 intake (r = 0.26) and maternal serum vitamin B-12 (r = 0.30). Controlling for the number of breastfeeds per day and vitamin B-12 intake from complementary foods, infant serum vitamin B-12 was associated with maternal serum vitamin B-12 (r = 0.31; P < 0.001) but not breast milk vitamin B-12, implicating a long-term effect of pregnancy status on infant vitamin B-12 status at 12 mo postpartum. PMID:22131550

Deegan, Kathleen L; Jones, Katherine M; Zuleta, Clara; Ramirez-Zea, Manuel; Lildballe, Dorte L; Nexo, Ebba; Allen, Lindsay H

2012-01-01

139

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. PMID:19934397

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

2010-01-01

140

Consumption of a functional fermented milk containing collagen hydrolysate improves the concentration of collagen-specific amino acids in plasma.  

PubMed

Clinical studies have shown that collagen hydrolysate (CH) may be able to protect joints from damage, strengthen joints, and reduce pain from conditions like osteoarthritis. CH is a collection of amino acids and bioactive peptides, which allows for easy absorption into the blood stream and distribution in tissues. However, although various matrices have been studied, the absorption of specific amino acids from CH added to a fresh fermented milk product (FMP) was not studied. The primary objective of the present study was to compare the plasma concentrations of four representative amino acids from the CH (glycine, proline, hydroxyproline, and hydroxylysine) contained in a single administration of a FMP with that of a single administration of an equal amount of neat hydrolyzed collagen. These four amino acids were chosen because they have already been used as markers of CH absorption rate and bioavailability. This was a single-center, randomized open, and crossover study with two periods, which was performed in 15 healthy male subjects. The subjects received randomly and in fasted state a single dose of product 1 (10 g of CH in 100 mL of FMP) and product 2 (10 g of CH dissolved in 100 mL of water) separated by at least 5 days. After administration, the subjects were assessed for plasma concentrations of amino acids and for urine concentrations of hydroxyproline. After FMP administration, mean values of the maximal concentration (Cmax) of the four amino acids were greater than after ingredient administration (p < 0.05). This effect was related to an increased Cmax of proline (p < 0.05). In conclusion, because of their physicochemical characteristics, the fermentation process, and the great homogeneity of the preparation, this milk product improves the plasma concentration of amino acids from CH, that is, proline. The present study suggests an interesting role for FMP containing CH to improve the plasmatic availability of collagen-specific amino acids. Hence, this FMP product could be of potential interest in the management of joint diseases. PMID:18707117

Walrand, Stephane; Chiotelli, Eleni; Noirt, Florence; Mwewa, Sandrine; Lassel, Taous

2008-09-10

141

Effect of prepartum photoperiod and melatonin feeding on milk production and prolactin concentration in dairy heifers and cows.  

PubMed

Holstein multiparous cows (n = 29) and primiparous heifers (n = 32) calving over a 1-yr period were subjected to photoperiod-melatonin treatments according to a 2 × 3 factorial design. Starting 8 wk before expected calving, all animals were subjected to 1 of the following treatments: 8h of light and 16 h of dark (8L:16D), 16 h of light and 8h of dark (16L:8D), or 16L:8D plus melatonin feeding (16L:8D-melatonin). Each day at 1355 h, the animals in the melatonin treatment received orally a gelatin capsule containing 25mg of melatonin. The treatments ended at calving, when the animals were moved to the lactation barn; all animals were then subjected to about 16 h of light per day. At the beginning and end of the treatment period before calving, blood samples were taken from 6 heifers and 6 cows through a jugular cannula for 24h at 30-min intervals to monitor serum melatonin and prolactin concentrations. Milk production in the heifers was not affected by the photoperiod treatments. Early-lactation milk production was higher in the cows exposed to the short-day photoperiod than in those exposed to a long-day photoperiod (16L:8D and 16L:8D-melatonin), with averages of 36.7 ± 0.9, 33.1 ± 0.8, and 34.1 ± 0.9 kg/d for 8L:16D, 16L:8D, and 16L:8D-melatonin, respectively. Photoperiod had no effect on late-lactation milk production in the cows. During lactation, the dry matter intake of heifers was not affected by the treatments, but dry matter intake of the cows exposed to a short-day photoperiod was greater than that of the cows exposed to a long-day photoperiod. Feed efficiency of heifers was improved by short-day photoperiod. During the treatment period, prolactin concentration was lower in the animals exposed to a short-day photoperiod than in those exposed to a long-day photoperiod, was lower with the 16L:8D-melatonin treatment than with the 16L:8D treatment, and tended to be lower with the 8L:16D treatment than with the 16L:8D-melatonin treatment, with averages of 3.5 ± 0.8, 9.9 ± 0.8, and 6.0 ± 0.8 ng/mL for 8L:16D, 16L:8D, and 16L:8D-melatonin, respectively. In early lactation, prolactin concentration was lower in the heifers exposed to the 16L:8D photoperiod during the dry period than in those exposed to the 8L:16D photoperiod or fed melatonin. In conclusion, a short-day photoperiod during the dry period transiently increases milk production of cows and the feed efficiency of heifers in the following lactation. However, melatonin cannot be used to mimic a short-day photoperiod during the dry period. PMID:24704221

Lacasse, P; Vinet, C M; Petitclerc, D

2014-06-01

142

Effect of feeding linseed oil in diets differing in forage to concentrate ratio: 1. Production performance and milk fat content of biohydrogenation intermediates of ?-linolenic acid.  

PubMed

To evaluate the interaction between the levels of dietary concentrate and linseed oil (LO) on milk fatty acid (FA) profile, 24 Holstein cows were used in a randomised complete block design based on days in milk, with a 2×2 factorial arrangement of treatments. Within each block, cows were fed one of four experimental diets containing 30% concentrate (LC) or 70% concentrate (HC), without LO (NLO) or with LO supplemented at 3% of dietary dry matter. Milk FA profiles were analysed with a special emphasis on the intermediates of the predominant trans-11, and a putative trans-13 pathways of ruminal biohydrogenation of cis-9, cis-12, cis-15 18:3. Feeding LO increased the concentrations of cis-9, cis-12, cis-15 18:3 and trans-11, cis-15 18:2 in milk fat, and these increases were of a higher magnitude when LO was added in HC as compared with LC diet (interaction of LO by concentrate). A treatment interaction was also observed for the level of trans-11 18:1 which was higher when feeding LO, but for which the increase was more pronounced with the LC as compared with HC diet. The concentrations of cis-15 18:1 and cis-9, trans-11, cis-15 18:3 were higher in cows fed LO, but feeding HC diets decreased milk fat content of cis-15 18:1 and a tendency for a decrease in cis-9, trans-11, cis-15 18:3 was apparent. Feeding LO increased milk fat content of trans-13 18:1 and cis-9, trans-13 18:2, while the concentrations of these two isomers were not affected by the level of dietary concentrates. The isomer cis-9, trans-13, cis-15 18:3 has not been detected in any of the milk samples. In conclusion, interactions were observed between LO and dietary concentrates on the proportions of some intermediates of the trans-11 biohydrogenation pathway. The presence of trans-13 18:1 and cis-9, trans-13 18:2 supports the existence of a trans-13 pathway, but an 18:3 intermediate with a trans-13 double bond has not been identified. PMID:24433586

Saliba, Leacady; Gervais, Rachel; Lebeuf, Yolaine; Chouinard, P Yvan

2014-02-01

143

SOURCE ASSESSMENT: UREA MANUFACTURE  

EPA Science Inventory

The report gives results of an evaluation of the potential environmental effects of air emissions from the production of urea. Urea production in the U.S. was 3.45 million metric tons in 1975. Major products were urea solution (38%), granulated solid material (53%), and prilled s...

144

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.

2007-02-01

145

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

2001-01-01

146

Effect of dietary N-carbamoylglutamate on milk production and nitrogen utilization in high-yielding dairy cows.  

PubMed

The objective of the current study was to investigate the effect of N-carbamoylglutamate (NCG) supplementation on milk production and nitrogen (N) utilization in Chinese Holstein dairy cows. Sixty multiparous cows (78±17.3 d in milk, 635±61.00kg of body weight, and 41.9±7.9kg/d milk yield; mean ± SD) were blocked by parity, days in milk, and milk yield and randomly allocated to 1 of 4 groups, each of which was fed a dietary treatment containing 0 (control), 10, 20, or 30g of NCG/d. Milk yield was recorded weekly. Dry matter intake, milk composition, plasma variables, and urea N contents in plasma, urine, and milk were determined every other week. Blood samples were collected from the coccygeal vein. Rumen microbial protein synthesis was estimated based on the purine derivatives in the urine. Dry matter intake was found to be similar between the treatments. Addition of 20g of NCG/d tended to increase milk yield (40.2 vs. 38.1kg/d) and increased the content (2.83 vs. 2.74%) and yield (1.12 vs. 1.02kg/d) of milk protein compared with the control. The yield and content of milk fat were similar between the treatments, whereas the contents of lactose and total solids increased linearly with an increase in NCG. Dietary supplementation of NCG linearly increased the plasma nitric oxide level and decreased the plasma ammonia N level. Compared with the control, the plasma Arg concentration in cows fed 10, 20, and 30g of NCG/d was increased by 1.1, 10.4, and 16.0%, respectively. The urea N concentrations in the milk, plasma, and urine decreased with the addition of NCG, although the lowest urea N concentrations were observed with the addition of 20g of NCG/d. The conversion of dietary crude protein to milk protein exhibited quadratic trends of improvement by NCG supplementation, with a peak at 20g of NCG/d. The rumen microbial protein synthesis was not altered by NCG supplementation, but the metabolizable protein tended to show a quadratic increase in cows fed 20g of NCG/d. In conclusion, supplementation of 20g of NVG/d may alter the plasma metabolites, optimize the AA profile, increase the metabolizable protein utilization, and thereby improve the lactation performance and N utilization of high-yielding dairy cows. PMID:24485674

Chacher, B; Zhu, W; Ye, J A; Wang, D M; Liu, J X

2014-04-01

147

Near-infrared spectroscopic sensing system for on-line milk quality assessment in a milking robot  

Microsoft Academic Search

A near-infrared (NIR) spectroscopic sensing system was constructed on an experimental basis. This system enabled NIR spectra of raw milk to be obtained in an automatic milking system (milking robot system) over a wavelength range of 600–1050nm. Calibration models for determining three major milk constituents (fat, protein and lactose), somatic cell count (SCC) and milk urea nitrogen (MUN) of unhomogenized

Masataka Kawasaki; Shuso Kawamura; Maki Tsukahara; Shigeru Morita; Michio Komiya; Motoyasu Natsuga

2008-01-01

148

Estimation of genetic and crossbreeding parameters of fatty acid concentrations in milk fat predicted by mid-infrared spectroscopy in New Zealand dairy cattle.  

PubMed

The objective of this study was to estimate heritability and crossbreeding parameters (breed and heterosis effects) of various fatty acid (FA) concentrations in milk fat of New Zealand dairy cattle. For this purpose, calibration equations to predict concentration of each of the most common FAs were derived with partial least squares (PLS) using mid-infrared (MIR) spectral data from milk samples (n=850) collected in the 2003-04 season from 348 second-parity crossbred cows during peak, mid and late lactation. The milk samples produced both, MIR spectral data and concentration of the most common FAs determined using gas chromatography (GC). The concordance correlation coefficients (CCC) between the concentration of a FA determined by GC and the PLS equation ranged from 0.63 to 0.94, suggesting that some prediction equations can be considered to have substantial predictive ability. The PLS calibration equations were then used to predict the concentration of each of the fatty acids in 26,769 milk samples from 7385 cows that were herd-tested during the 2007-08 season. Data were analysed using a single-trait repeatability animal model. Shorter chain FA (16:0 and below) were significantly higher (P<0.05) in Jersey cows, while longer chain, including unsaturated longer chain FA were higher in Holstein-Friesian cows. The estimates of heritabilities ranged from 0.17 to 0.41 suggesting that selective breeding could be used to ensure milk fat composition stays aligned to consumer, market and manufacturing needs. PMID:25052435

Lopez-Villalobos, Nicolas; Spelman, Richard J; Melis, Janine; Davis, Stephen R; Berry, Sarah D; Lehnert, Klaus; Holroyd, Stephen E; MacGibbon, Alastair K H; Snell, Russell G

2014-08-01

149

Effects of dose, administration route, and/or vehicle on decabromodiphenyl ether concentrations in plasma of maternal, fetal, and neonatal rats and in milk of maternal rats.  

PubMed

The effects of route and vehicle on blood and milk levels of decabromodiphenyl ether (DecaBDE; CASRN 1163-19-5) were investigated in the rat to assist in the design and conduct of a developmental neurotoxicity study. Blood plasma and/or milk concentrations were determined in dams, fetuses, and/or nursing pups after repeated DecaBDE administration by gavage throughout gestation or gestation and lactation using corn oil (CO) or soyaphospholipon/Lutrol F 127-water (SPL) as the vehicle. The impact of vehicle on plasma levels was also investigated in pups derived from naive dams after a single postnatal dose. This study reports for the first time fetal and neonatal plasma concentrations concurrent with those of maternal plasma and/or milk. Higher concentrations of DecaBDE were achieved in plasma and in milk with CO than with SPL. Furthermore, pups derived from dams treated with only SPL were lower in body weight, compared with those from dams treated with either CO, CO and DecaBDE, or SPL and DecaBDE. The study further shows that exposure to DecaBDE is relatively consistent across the dose range of 100 to 1000 mg/(kg · day) when administered in CO. PMID:20581093

Biesemeier, John A; Beck, Melissa J; Silberberg, Hanna; Myers, Nicole R; Ariano, John M; Bodle, Eric S; Sved, Daniel W; Jacobi, Sylvia; Stump, Donald G; Hardy, Marcia; Stedeford, Todd

2010-10-01

150

Use of urea–molasses–multinutrient block and urea-treated rice straw for improving dairy cattle productivity in Vietnam  

Microsoft Academic Search

After conducting a preliminary survey, a feeding trial was carried out to determine the effect of urea–molasses–multinutrient block (UMMB) and urea-treated rice straw (UTRS) as a feed supplement on the productivity of dairy cows. Sixty Holstein–Friesian crossbred cows on 11 smallholder farms were divided equally into control, UMMB and UTRS supplementation groups. Milk yield and feed intake were recorded daily.

Doan Duc Vu; Le Xuan Cuong; Chung Anh Dung; Pham Ho Hai

1999-01-01

151

Mastitis Is Associated with Increased Free Fatty Acids, Somatic Cell Count, and Interleukin-8 Concentrations in Human Milk  

PubMed Central

Abstract Background Research in bovine lactation has demonstrated that milk produced by a mammary gland displaying inflammation-based symptoms of mastitis has increased levels of free fatty acids (FFAs) compared with milk produced by a contralateral asymptomatic gland. However, the effects of mastitis on lipid classes in milk have not been investigated in humans. Methods The study described here compared milk collected from the symptomatic breast of women with mastitis (n=14) with that collected from the contralateral asymptomatic breast to determine if mastitis caused alterations in the quantity of total lipids, FFAs, and phospholipids (PLs), as well as the fatty acid profiles of these lipid classes. To assess their efficacy as biomarkers of mastitis, samples were also analyzed for selected markers of local inflammation: sodium, somatic cell count (SCC), and interleukin-8 (IL-8). Results FFAs were higher in milk from the mastitic breast compared with that from the healthy breast (1.31 vs. 1.07±0.10?g/100?g of lipid, p<0.05). Similarly, SCC and IL-8 were elevated roughly 10-fold in milk from mastitic breasts, compared with milk from healthy breasts, and sodium tended to be higher in milk from mastitic breasts (p<0.10). However, there were no differences in total lipid, PLs, or fatty acid profiles within each lipid class. Conclusions In summary, mastitis is associated with increased lipolysis in the human breast but not alterations in milk fat synthesis, as evidenced by a lack of alteration in total milk lipids. Additionally, these results indicate that SCC and IL-8 may be better indicators of mammary inflammation than sodium content. PMID:22283504

Hunt, Katherine M.; Williams, Janet E.; Shafii, Bahman; Hunt, Martha K.; Behre, Rebecca; Ting, Robert; McGuire, Michelle K.

2013-01-01

152

Effect of protein, nonprotein-soluble components, and lactose concentrations on the irreversible thermal denaturation of beta-lactoglobulin and alpha-lactalbumin in skim milk.  

PubMed

The effect of protein, nonprotein-soluble components, and lactose concentrations on the irreversible denaturation of beta-lactoglobulin (beta-LG) and alpha-lactalbumin (alpha-LA) in reconstituted skim milk samples was studied over a wide temperature range (75-100 degrees C). The irreversible thermal denaturation of beta-LG had a reaction order of 1.5 and that of alpha-LA had a reaction order of 1.0 in all systems and under all conditions. The rates of irreversible denaturation of beta-LG and alpha-LA were markedly dependent upon the composition of the milk. At all temperatures, the irreversible denaturations of beta-LG and alpha-LA were enhanced at a higher protein concentration and were retarded when the nonprotein-soluble components and lactose concentrations were increased. The effects of increasing the concentrations of lactose and nonprotein-soluble components were interpreted using the preferential hydration theory and allowed for the interpretation of the changes in the denaturations of beta-LG and alpha-LA when the milk total solids concentration was increased. PMID:16968103

Anema, Skelte G; Lee, Siew Kim; Klostermeyer, Henning

2006-09-20

153

Milk Allergy  

MedlinePLUS

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 ...

154

Intravaginal administration of lactic acid bacteria modulated the incidence of purulent vaginal discharges, plasma haptoglobin concentrations, and milk production in dairy cows.  

PubMed

This investigation studied the effects of intravaginal administration of a mixture of lactic acid bacteria (LAB) on the incidence of purulent vaginal discharges (PVD), plasma haptoglobin concentrations, and milk production in dairy cows. A total of 82 pregnant primiparous and multiparous Holstein dairy cows were used in this study. Half of the cows received intravaginally 1mL of LAB at 10(10)-10(12)cfu/mL and the other half 1mL of reconstituted skim milk (i.e., carrier) (controls). Administration of LAB was conducted once per wk during 2 and 1wk before the expected day of calving and at 1, 2, 3, and 4wk postpartum. Data demonstrated that intravaginal administration of LAB decreased the occurrence of PVD at 3wk postpartum (P<0.05). Concentrations of plasma haptoglobin, an acute phase protein often associated with uterine infections, was lower in cows treated with the LAB mixture at 2wk (P<0.001) and 3wk (P<0.05) postpartum. Treatment with LAB did not improve overall pregnancy rate, but the treated multiparous cows produced more milk than their control counterparts (P<0.05), whereas no difference was observed in primiparous cows regarding milk yield (P>0.05). Overall, this is the first study demonstrating that intravaginal LAB administration lowers the incidence of PVD and enhances milk production in dairy cows. Further research is warranted to evaluate the effects of LAB on reproductive performance in a larger cohort of cows. PMID:24612560

Ametaj, B N; Iqbal, S; Selami, F; Odhiambo, J F; Wang, Y; Gänzle, M G; Dunn, S M; Zebeli, Q

2014-04-01

155

Effects of urea formaldehyde condensation polymer treatment of flaxseed on ruminal digestion and lactation in dairy cows.  

PubMed

Flaxseed is a potent source of the n-3 fatty acid ?-linolenic acid (ALA), yet most ALA is lost during ruminal biohydrogenation when ground flaxseed is fed to ruminants. Heat processing and urea formaldehyde condensation polymer (UFCP) treatment of flaxseed were investigated as possible means of protecting ALA from ruminal degradation. Ground flaxseed (GF), heated ground flaxseed (HGF), or UFCP-treated ground flaxseed (UFCPGF) were incubated for 0, 4, 8, and 12h in 4 ruminally cannulated multiparous lactating Holstein cows. Compared with GF, HGF and UFCPGF decreased ruminal disappearance of dry matter, crude protein, and ALA. Pepsin-digestible protein remaining after 12h of ruminal incubation was greater for UFCPGF and HGF than for GF. Twenty-four lactating Holstein cows (207 ± 37 d in milk, 668 ± 66 kg of body weight, and 1.33 ± 0.56 lactations) were then used in a randomized complete block design experiment with a basal feeding period to assess effects of flaxseed treatment on ALA enrichment of plasma and milk as well as lactational performance. No evidence existed that supplementation of HGF and UFCPGF affected dry matter intake, milk fat content, milk protein content, or energy-corrected milk yield, but UFCPGF marginally decreased milk yield compared with HGF. Plasma concentration of ALA was not affected by treatment. Concentrations of n-3 fatty acids and conjugated linoleic acids in milk fat were increased by UFCPGF relative to HGF, but ALA yield was not affected. Taken together, in situ results suggest that heat-treated flaxseed, with or without UFCP treatment, slowed ruminal disappearance of ALA. Feeding UFCP-treated flaxseed failed to alter ALA content of plasma or milk ALA yield relative to heating alone. PMID:23548281

Hawkins, A; Yuan, K; Armendariz, C K; Highland, G; Bello, N M; Winowiski, T; Drouillard, J S; Titgemeyer, E C; Bradford, B J

2013-06-01

156

Utilization of roughages and concentrates relative to that of milk replacer increases strongly with age in veal calves.  

PubMed

We aimed to investigate the feeding values of milk replacer (MR), roughage, and concentrates for veal calves in a paired-gain setting, thus avoiding any prior assumptions in feeding values and major differences in nutrient intakes. One hundred sixty male Holstein-Friesian calves at 2 wk of age and 45±0.2kg of body weight (BW) were included in the experiment. Calves were allocated to pens (5 calves per pen) and pens were randomly assigned to 1 of 4 solid feed (SF) levels: SF1, SF2, SF3, or SF4, respectively, and to 1 of 2 roughage-to-concentrate (R:C) ratios: 20:80 or 50:50. An adaptation period from wk 1 to 10 preceded the experimental period (wk 11 to 27). Total dry matter (DM) intake from SF was targeted to reach 20, 100, 180, and 260kg of DM for SF1 to SF4, respectively, during the 16-wk experimental period, and increased with preplanned, equal weekly increments. Roughage was composed of 50% corn silage and 50% chopped wheat straw based on DM. The quantity of MR provided was adjusted every 2 wk based on BW to achieve similar targeted rates of carcass gain across treatments. The reduction in MR provided (in kg of DM) to realize equal rates of carcass gain with inclusion of SF (in kg of DM) differed between the R:C ratio of 50:50 (0.41kg of MR/kg of SF) and the R:C ratio of 20:80 (0.52kg of MR/kg of SF). As carcass gain unintentionally increased with SF intake, the paired-gain objective was not fully achieved. When adjusted for realized rates of carcass gain, calves fed an R:C ratio of 20:80 still required 10% less MR than calves fed an R:C ratio of 50:50 for equal rates of carcass gain, indicating that the utilization of SF for gain increased with concentrate inclusion. Averaged for the 16-wk experimental period, the feeding value of MR relative to that of concentrates and roughages was close to that predicted based on their respective digestible energy contents. Nevertheless, the feeding value of SF relative to that of MR increased substantially with age. Therefore, additivity in feeding values of these ration components cannot be assumed. The results of the current study may contribute to the development of new concepts for formulation of veal calf diets with substantial amounts of SF. PMID:25129492

Berends, H; van den Borne, J J G C; Mollenhorst, H; van Reenen, C G; Bokkers, E A M; Gerrits, W J J

2014-10-01

157

Zinc in human milk  

Microsoft Academic Search

Zinc concentration in breast milk varies within and between mothers. Neither environmental (zinc intake — either in natural food or supplemented, nutrient interaction, cigarette smoking, and oral contraceptives) nor constitutional (premature delivery, number of children, teen age pregnancy, undernutrition, infection, and diabetes) variables consistently affected zinc concentration or its rate of decrease in breast milk. Stage of lactation is the

Jose G. Dorea

2000-01-01

158

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.

2012-03-01

159

Milk Production Response of Dairy Cows Fed High-Moisture Grass Silage. I. Effect of Varying Levels of Hay and Concentrate1  

Microsoft Academic Search

Varying levels of bay and concentrate were fed in conjunction with high-moisture grass silage ad tibitum to 16 lactating cows, to determine the effects of these ration variables on milk production and composi- tion. Feeding the higher level of concen- trate (0.6 kg\\/kg 4% FCM over 8.16 kg) resulted in the production of more 4% FCM (P < 0.01), as

F. R. Murdock; A. S. Hodgson

1967-01-01

160

Effect of skim milk powder, soy protein concentrate and sucrose on the dehydration behaviour, texture, color and acceptability of mango leather  

Microsoft Academic Search

A study was carried out on the dehydration behaviour, texture, color and sensory acceptability of mango leather. Soy protein concentrate, skim milk powder and sucrose were added at levels of 0%, 4.5% and 9% to improve nutritive value and sweetness of the product. It took 7.60 h of drying time at 60±1°C for mango leather to reach 10% moisture content

Hardeep Singh Gujral; Gaurav Khanna

2002-01-01

161

The association between local fish consumption and DDE, mirex, and HCB concentrations in the breast milk of Mohawk women at Akwesasne  

Microsoft Academic Search

A study was conducted to assess the extent to which the consumption of local fish contaminated with p,p?-dichlorodiphenyl dichloroethylene (p,p?-DDE), mirex, and hexachlorobenzene (HCB) has impacted the concentrations of these compounds in the milk of nursing Mohawk women residing along the St. Lawrence River. From 1986 to 1992, 97 Mohawk women were interviewed, and each donated a one-time sample of

EDWARD F FITZGERALD; SYNI-AN HWANG; DEBRA A DERES; BRIAN BUSH; KATSI COOK; PRISCILLA WORSWICK

2001-01-01

162

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

PubMed

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

2013-06-01

163

Intraduodenal milk protein concentrate augments the glycemic and food intake suppressive effects of DPP-IV inhibition.  

PubMed

Glucagon-like peptide-1 (GLP-1) is an incretin hormone released from intestinal L-cells in response to food entering into the gastrointestinal tract. GLP-1-based pharmaceuticals improve blood glucose regulation and may hold promise for obesity treatment, as GLP-1 drugs reduce food intake and body weight in humans and animals. In an effort to improve GLP-1 pharmacotherapies, we focused our attention on macronutrients that, when present in the gastrointestinal tract, may enhance GLP-1 secretion and improve glycemic regulation and food intake suppression when combined with systemic administration of sitagliptin, a pharmacological inhibitor of DPP-IV (enzyme responsible for GLP-1 degradation). In particular, previous data suggest that specific macronutrient constituents found in dairy foods may act as potent secretagogues for GLP-1 and therefore may potentially serve as an adjunct dietary therapy in combination with sitagliptin. To directly test this hypothesis, rats received intraperitoneal injections of sitagliptin (6 mg/kg) or saline vehicle followed by intraduodenal infusions of either milk protein concentrate (MPC; 80/20% casein/whey; 4 kcal), soy protein (nondairy control infusate; 4 kcal), or 0.9% NaCl. Food intake was assessed 30 min postinfusion. In separate studies, regulation of blood glucose was examined via a 2-h oral glucose tolerance test (2 g/kg) following identical sitagliptin treatment and intraduodenal nutrient infusions. Collectively, results show that intraduodenal MPC, but not soy protein, significantly enhances both the food intake suppression and improved control of blood glucose produced by sitagliptin. These data support the hypothesis that dietary intake of dairy protein may be beneficial as an adjunct behavioral therapy to enhance the glycemic and food intake suppressive effects of GLP-1-based pharmacotherapies. PMID:24352410

Olivos, Diana R; McGrath, Lauren E; Turner, Christopher A; Montaubin, Orianne; Mietlicki-Baase, Elizabeth G; Hayes, Matthew R

2014-02-01

164

Maternal risk factors associated with increased dioxin concentrations in breast milk in a hot spot of dioxin contamination in Vietnam.  

PubMed

This study looked to identify determinants of exposure to dioxin in breast milk from breast-feeding women in a hot spot of dioxin exposure in Vietnam. Breast milk was collected from 140 mothers 1 month after delivery. The risk factors investigated included length of residency, drinking of well water and the frequency of animal food consumption. Cluster analysis was performed to identify dietary patterns of fish and meat portions, fish variety and egg variety. Residency, age and parity were clearly associated with increased dioxin levels. Drinking well water and the consumption of marine crab and shrimps were related to higher levels of furans in breast milk. The consumption of quail eggs also appeared to be associated with increased levels of some dioxin isomers in this area. Some mothers who ate no or less meat than fish and mothers who consumed more freshwater fish than marine fish had lower levels of dioxins in their breast milk. However, the type of water and the eating habits of mothers contributed only partly to the increased dioxin levels in their breast milk; the length of residency was the most important risk factor associated with increased dioxin body burdens of mothers. PMID:24149970

Anh, Nguyen Thi Nguyet; Nishijo, Muneko; Tai, Pham The; Maruzeni, Shoko; Morikawa, Yuko; Anh, Tran Hai; Van Luong, Hoang; Dam, Pham Minh; Nakagawa, Hideaki; Son, Le Ke; Nishijo, Hisao

2014-01-01

165

Performance of tropical dairy cows fed whole crop rice silage with varying levels of concentrate.  

PubMed

The objective of this experiment was to evaluate the effect of concentrate/milk yield ratios on feed intake, nutrient digestibility, rumen fermentation efficiency, and milk production in dairy cows fed with a basal diet of whole crop rice silage (WCRS). Sixteen crossbred cows (75 % Holstein-Friesian (HF) and 25 % Thai cows) in mid-lactation were assigned to four dietary treatments in a completely randomized design. Treatments corresponding to four concentrate/milk yield ratios (0, 1:1, 1:2, and 1:3 (kg/kg)) were used. All cows were offered WCRS (with 1.5 % urea and 3 % molasses) ad libitum. Silage and concentrate were fed individually twice a day. Results revealed that dry matter intake (12.8-14.5 kg/day), nutrient digestibility (62.5-68.7 %), and rumen fermentation efficiency were not significantly affected by concentrate supplementation. Milk yield (10.2-11.5 kg/day) and milk composition were similar between cows fed with sole WCRS and those supplemented with concentrate mixture, although milk fat tended to increase in cows fed with sole WCRS. In conclusion, sole WCRS fed to dairy cows without concentrate supplementation resulted in similar feed intake, nutrient digestibility, rumen fermentation, and milk production as compared to those supplemented with concentrate in lactating dairy cows. These results suggest that in tropical areas where rice crop is surplus, WCRS could sustain reasonable levels of milk production among dairy cows with little or no concentrate supplementation provided that urea and molasses are included in the silage. PMID:24048824

Wanapat, Metha; Kang, Sungchhang; Khejornsart, Pichad; Pilajun, Ruangyote; Wanapat, Sadudee

2014-01-01

166

Intakes and breast-milk concentrations of essential fatty acids are low among Bangladeshi women with 24-48-month-old children.  

PubMed

Maternal fat intake and adipose reserves are major sources of PUFA during lactation. The present study examined the cross-sectional relationship between prolonged breast-feeding and maternal BMI, assessed adequacy of fat intake among lactating and non-lactating mothers of children 24-48 months of age and determined breast-milk fatty acid composition. Multi-stage sampling was used to select a representative sample of mothers from two rural districts in Bangladesh (n 474). Dietary data were collected during two non-consecutive 24 h periods via 12 h in-home daytime observations and recall. The National Cancer Institute method for episodically consumed foods was used to estimate usual intake distributions. Breast milk samples were collected from ninety-eight women, and breast-milk fatty acid methyl esters were quantified using GC. Approximately 42 % of lactating v. 26 % of non-lactating mothers were underweight (BMI < 18·5 kg/m2; P = 0·0003). The maternal diet was low in total fat (approximately 8 % of mean total energy) and food sources of PUFA, including oil and animal source foods, resulting in a low estimated mean total consumption of PUFA (5·1 g/d). Almost all women were estimated to consume less than the recommended intake levels for total fat, total PUFA, ?-linolenic acid (ALA) and DHA. Median breast-milk linoleic acid (8·5 % weight) and ALA (0·2 %) concentrations were among the lowest reported in the literature, in contrast with arachidonic acid (0·5 %) and DHA (0·3 %) concentrations, which were mid-range. Bangladeshi women in general, and especially those who practise prolonged breast-feeding, may benefit from increased consumption of food sources of PUFA. PMID:21324215

Yakes, Elizabeth A; Arsenault, Joanne E; Munirul Islam, M; Hossain, Mohammad B; Ahmed, Tahmeed; Bruce German, J; Gillies, Laura A; Shafiqur Rahman, Ahmed; Drake, Christiana; Jamil, Kazi M; Lewis, Bess L; Brown, Kenneth H

2011-06-01

167

Detection of cow milk adulteration in yak milk by ELISA.  

PubMed

In the current study, a simple, sensitive, and specific ELISA assay using a high-affinity anti-bovine ?-casein monoclonal antibody was developed for the rapid detection of cow milk in adulterated yak milk. The developed ELISA was highly specific and could be applied to detect bovine ?-casein (10-8,000?g/mL) and cow milk (1:1,300 to 1:2 dilution) in yak milk. Cross-reactivity was <1% when tested against yak milk. The linear range of adulterant concentration was 1 to 80% (vol/vol) and the minimum detection limit was 1% (vol/vol) cow milk in yak milk. Different treatments, including heating, acidification, and rennet addition, did not interfere with the assay. Moreover, the results were highly reproducible (coefficient of variation <10%) and we detected no significant differences between known and estimated values. Therefore, this assay is appropriate for the routine analysis of yak milk adulterated with cow milk. PMID:25151876

Ren, Q R; Zhang, H; Guo, H Y; Jiang, L; Tian, M; Ren, F Z

2014-10-01

168

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...

169

Milk Pricing  

E-print Network

This publication discusses the federal orders that govern the marketing of milk. The production location and form of the milk product affect the way it is priced. The different classes of milk and their prices are explained in detail....

Anderson, David P.; Haigh, Michael; Stockton, Matthew; Schwart Jr., Robert B.

2001-09-10

170

Biohydrolysis of urea from urea-bearing wastewater.  

PubMed

Biological stabilization of urea is a two staged process; (i) urea hydrolysis and (ii) ammonia stripping/nitrification-denitrification. Ammonia thus produced is either stripped off by usual methods or after converting into nitrate using chemoautotrophic bacteria. On denitrification, nitrate is finally converted into nitrogen gas by means of heterotrophic bacteria. Details of stabilization of urea from urea bearing wastewater using urea biohydrolyser are presented in this paper. PMID:14672371

Pathe, Pradhyumna P; Tapas, Nandy; Kaul, Santosh N; Deshpande, Chandrasekhar V; Szpyrkowicz, Lidia

2003-01-01

171

Short communication: Supplementing lysine and methionine in a lactation diet containing a high concentration of wet corn gluten feed did not alter milk protein yield.  

PubMed

Primiparous (n=33) and multiparous (n=63) lactating Holstein cows (186±51 d in milk) were used to evaluate the effects of supplementing metabolizable amino acids using lysine in a matrix of Ca salts of fatty acids (Megamine-L, Arm & Hammer Animal Nutrition, Princeton, NJ) and the isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid (MetaSmart, Adisseo Inc., Antony, France) in diets containing >26% wet corn gluten feed (dry matter basis). Cows were blocked by production level, parity, and pregnancy status, then randomly assigned to 1 of 8 pens and allowed a 7-d adaption period before receiving dietary treatments for 28 d. Pens were assigned randomly to either of 2 diets formulated to differ by metabolizable amino acid supply. Dry matter intake and production were monitored daily and milk components analyzed 3d/wk. Data were analyzed using mixed models with repeated measures. The original design of the study consisted of a control diet predicted to be deficient in lysine and methionine; however, after ingredient nutrients were analyzed and modeled with animal requirements at dry matter intake [26.6±0.35 kg/d (mean ± SEM)] and milk production levels achieved during the study (40.1±0.46 kg/d), only marginal deficiencies were predicted for the control (-8.1g/d for lysine; -1g/d for methionine) according to the National Research Council method, whereas the Cornell Net Carbohydrate and Protein System 5.0 and 6.1 models indicated positive balances for these amino acids (25.9 and 21.8 g/d for lysine, 14.7 and 18.9 g/d for methionine, respectively). Supplementing 30 g/d of metabolizable lysine in a Ca soap matrix and 2.4 g/d of metabolizable methionine as 2-hydroxy-4-(methylthio) butanoic acid led to positive predicted lysine and methionine balances by all 3 models, and predicted metabolizable lysine-to-methionine ratios ranging from 2.9 to 3.1. No treatment effects were observed for dry matter intake, milk yield, milk component concentrations or yields, or energy-corrected milk yield. Despite the negative lysine balance and low lysine-to-methionine ratio predicted by the National Research Council model, results provided no evidence of a lysine deficiency in the control diet. PMID:23746581

Mullins, C R; Weber, D; Block, E; Smith, J F; Brouk, M J; Bradford, B J

2013-08-01

172

Long-Term Effects of Subacute Ruminal Acidosis (SARA) on Milk Quality and Hepatic Gene Expression in Lactating Goats Fed a High-Concentrate Diet  

PubMed Central

Purpose The mechanism underlying the decline in milk quality during periods of feeding high-concentrate diets to dairy ruminants is not well documented. The aim of this study was to investigate the metabolic changes in the liver that contribute to the input of substrate precursors to the mammary gland after feeding a high-concentrate diet to lactating goats for a long period. Experimental Design Eight mid-lactating goats with rumen cannulas were randomly assigned to two groups. For 9 weeks, the treatment group was fed a high-concentrate diet (60% concentrate of dry matter, HC) and the control group was fed a low-concentrate diet (40% concentrate of dry matter, LC). Ruminal fluid, plasma, and liver tissues were sampled, microarray techniques and real-time polymerase chain reaction were used to evaluate metabolic parameters and gene expression in liver. Results Feeding a 60%-concentrate diet for 9 weeks resulted in a significant decrease in rumen pH. Changes in fat and protein content also occurred, which negatively affected milk quality. Plasma levels of leptin (p?=?0.058), non-esterified fatty acid (p?=?0.071), and glucose (p?=?0.014) increased markedly in HC group. Plasma cortisol concentration was significantly elevated in the treatment group (p<0.05). Expression of the glucocorticoid receptor protein gene was significantly down-regulated (p<0.05) in the liver. The expression of genes for interleukin 1?, serum amyloid A, C-reactive protein, and haptoglobin mRNA was significantly increased (p<0.05) in the HC group. GeneRelNet analysis showed that gene expression involved in inflammatory responses and the metabolism of lipids, protein, and carbohydrate were significantly altered by feeding a high-concentrate diet for 9 weeks. Conclusions Activation of the acute phase response and the inflammatory response may contribute to nutrient partitioning and re-distribution of energy in the liver, and ultimately lead to a decline in milk quality. PMID:24376594

Dong, Haibo; Wang, Shaoqing; Jia, Yuanyuan; Ni, Yingdong; Zhang, Yuanshu; Zhuang, Su; Shen, Xiangzhen; Zhao, Ruqian

2013-01-01

173

Original article Response of milk yield, plasma cortisol,  

E-print Network

Original article Response of milk yield, plasma cortisol, amino acids, urea and glucose to a single yield, plasma cortisol, free amino acids, urea and glucose in lactating cows. The animals were treated cortisol occurred within 10 min of administration of 6 IU ACTH. The maximum increase in plasma cortisol

Paris-Sud XI, Université de

174

Urea in the Tributaries of the Chesapeake and Coastal Bays of Maryland  

Microsoft Academic Search

Concentrations of dissolved urea were monitored in several Chesapeake Bay tributaries from 1998 to 2002. Urea is a commonly used agricultural fertilizer and is also a breakdown product of poultry manure, which is used as an additional source of fertilizer throughout the watershed. Two trends were apparent. First, in several of the tributaries, seasonal peaks in ambient urea concentration coincided

Patricia M. Glibert; T. Mark Trice; Bruce Michael

2005-01-01

175

Effect of feeding baled and stacked urea treated rice straw on the performance of crossbred cows  

Microsoft Academic Search

Crossbred dairy cows (2–4 lactations) in three groups (4 in each group) were fed with rations containing (1) untreated rice straw ad libitum plus 1kg concentrate supplement, (2) urea treated (4% urea; 50% moisture) rice straw stored in stack for 14 days, and (3) urea treated paddy straw compressed as bales and stored for 14 days. Extra concentrate supplement was

R. D. D Prasad; M. R Reddy; G. V. N Reddy

1998-01-01

176

Osmolyte counteracts urea-induced denaturation of alpha-chymotrypsin.  

PubMed

The stability of proteins is reduced by urea, which is methylamine and nonprotecting osmolyte; eventually urea destabilizes the activity and function and alters the structure of proteins, whereas the stability of proteins is raised by the osmolytes, which are not interfering with the functional activity of proteins. The deleterious effect of urea on proteins has been counteracted by methylamines (osmolytes), such as trimethylamine N-oxide (TMAO), betaine, and sarcosine. To distinctly enunciate the comparison of the counteracting effects between these methylamines on urea-induced denaturation of alpha-chymotrypsin (CT), we measured the hydrodynamic diameter (d(H)) and the thermodynamic properties (T(m), DeltaH, DeltaG(U), and DeltaC(p)) with dynamic light scattering (DLS) and differential scanning calorimeter (DSC), respectively. The present investigation compares the compatibility and counteracting hypothesis by determining the effects of methylamines and urea, as individual components and in combination at a concentration ratio of 1:2 (methylamine:urea) as well as various urea concentrations (0.5-5 M) in the presence of 1 M methylamine. The experimental results revealed that the naturally occurring osmolytes TMAO, betaine, and sarcosine strongly counteracted the urea actions on alpha-chymotrypsin. The results also indicated that TMAO counteracting the urea effects on CT was much stronger than betaine or sarcosine. PMID:19354310

Venkatesu, Pannur; Lee, Ming-Jer; Lin, Ho-Mu

2009-04-16

177

The effects of inclusion levels of urea-treated potato pulp silage in concentrate and roughage sources on finishing performance and carcass quality in cull beef cows.  

PubMed

ABSTRACT An experiment was conducted to determine the effects of inclusion levels of potato pulp silage in concentrate (0, 15, 30 or 45%; on a dry matter basis) and roughage sources (rice straw or wheat straw) on finishing performance and carcass quality of cull beef cows. Sixteen Japanese Black (Wagyu) mature cull cows (490 +/- 31 kg of BW) were used in this experiment. Increasing the levels of potato pulp silage in concentrate and roughage sources did not significantly affect feed intake in cows. In addition, the final body weight, daily gain and feed : gain ratio were not influenced by the inclusion levels of potato pulp silage in concentrate and the type of roughage. Increasing the inclusion levels of potato pulp silage in concentrate would probably decrease the marbling score. The L* values of the longissimus muscle (LM) tended to respond quadratically (P = 0.078) as the inclusion levels of potato pulp silage in concentrate increased, and was lowest for cows fed the concentrate which included 30% potato pulp silage. The a* and b* values of the LM and fat color were not affected by the inclusion levels of potato pulp silage in concentrate. No effects of roughage sources on finishing performance were observed. PMID:20163636

Sugimoto, Masahito; Saito, Waka; Ooi, Motoki; Sato, Yukinobu; Saito, Toshiro

2009-06-01

178

Transcobalamin from cow milk: isolation and physico-chemical properties.  

PubMed

The concentration of endogenous cobalamin (Cbl) in cow milk was 3.3 nM while the Cbl-binding capacity was 0.05 nM. Both endogenous and newly added Cbl showed similar quantitative distribution between a 280 kDa protein complex (45%) and a 43 kDa Cbl-binder (55%). Long time incubation, as well as urea treatment, was accompanied by a slow release of the 43 kDa Cbl-binder from the 280 kDa fraction. No other Cbl-binding proteins appeared after these procedures. The 43 kDa binder from cow milk, depleted of the ligand by urea treatment, reacted with Cbl even in the presence of a B12-analogue cobinamide (Cbi) at the ratio Cbl:Cbi = 1:40. The stokes radius of the binder changed from 2.7 nm for the Cbl-free protein to 2.5 nm for the Cbl-saturated form and the Cbl-saturated binder was able to displace human transcobalamin (TC) from the TC-receptor. The interaction between the protein and Cbl was significantly suppressed at pH 2.0. The N-terminal sequence of the purified 43 kDa Cbl-binder revealed homology with TC from human and rabbit plasma. In conclusion we have shown that TC is the main Cbl-binding protein in cow milk. This is surprising, since previous studies on human and rat milk have shown another Cbl-binder, apo-haptocorrin, to be the dominating Cbl-binding protein. PMID:8547333

Fedosov, S N; Petersen, T E; Nexø, E

1996-01-01

179

Aqueous urea solution destabilizes A 1622 oligomers D. K. Klimov*  

E-print Network

considered to be the primary pathogenic agents of the Alzheimer's disease (8). The amyloidogenic pathway, formation of soluble oligomeric intermediates, and gradual accumulation of protofibrils and fibril deposits in aqueous urea solution. High concentration of urea promotes the formation of -strand structures in A 16

Straub, John E.

180

Chemiresistor urea sensor  

DOEpatents

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)

1997-01-01

181

Effect of cassava hay and rice bran oil supplementation on rumen fermentation, milk yield and milk composition in lactating dairy cows.  

PubMed

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of 418±5 kg and 36±10 d in milk were randomly assigned according to a 2×2 factorial arrangement in a 4×4 Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g Ca(OH)2 (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, NH3-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DM, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA. PMID:25049491

Lunsin, R; Wanapat, M; Rowlinson, P

2012-10-01

182

Effect of Cassava Hay and Rice Bran Oil Supplementation on Rumen Fermentation, Milk Yield and Milk Composition in Lactating Dairy Cows  

PubMed Central

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of 418±5 kg and 36±10 d in milk were randomly assigned according to a 2×2 factorial arrangement in a 4×4 Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g Ca(OH)2 (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, NH3-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DM, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA. PMID:25049491

Lunsin, R.; Wanapat, M.; Rowlinson, P.

2012-01-01

183

Determination of L-hydroxyproline using hydrophilic interaction chromatography coupled to tandem mass spectrometry with lyophilized concentrated extraction in milk and dairy products.  

PubMed

In this study, a screening and confirmation method for the determination of l-hydroxyproline (Hyp) as a target compound in milk and dairy products using high-performance liquid chromatography with tandem mass spectrometry was developed. The samples were lyophilized after acidic hydrolysis, followed by cleanup with graphitized carbon black to remove pigments. Hyp was separated by a hydrophilic interaction chromatographic column and analyzed by high-performance liquid chromatography with tandem mass spectrometry working with multiple reaction monitoring mode using an electrospray ionization interface in a positive-ion mode. Average recoveries in spiked milk and dairy products ranged from 68.0 to 101.1% with relative standard deviations between 2.0 and 11.7% (n = 7). A reagent-matched standard calibration curve was used for quantification of Hyp, with linear correlation coefficient (R(2)) > 0.99 in the concentration range of 0.1-100 ?g/mL. The LOQs were from 0.25 to 5 mg/kg, which were usually sufficient to verify the Hyp in samples. The confirmation concentration of Hyp ranged from 10 to 50 mg/kg. PMID:24777951

Zhu, Ai-ling; Peng, Tao; Chen, Dong-dong; Wang, Ping; Wang, Guo-min; Wang, Jin-hua; Jiang, Hai-yang; Fan, Chun-lin; Chen, Ying

2014-07-01

184

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)

2010-03-19

185

Effect of grain and forage fractions of corn silage on milk production and composition in dairy cows.  

PubMed

Corn silage (CS) is associated with a reduction in milk fat content. The fact that CS is constituted of a grain and a forage fraction could explain this effect. This experiment evaluated the effect of grain fraction of CS on rumen fermentation, production performance and milk composition. Earless CS (ECS) was harvested after manually removing corn ears from the plant. Whole CS (WCS) was harvested from the same field on the same day. Eight (four ruminally fistulated) multiparous Holstein cows (84 days in milk) were utilized in a double 4 × 4 Latin square with 21-day periods. Treatments were (dry matter (DM) basis) (1) 23.0% WCS; (2) 12.4% ECS plus 10.6% high moisture corn (HMC) to obtain reconstituted CS (RCS); (3) 23.0% ECS; and (4) 23.0% timothy silage (TS). Diets were formulated to be isonitrogenous and were fed as total mixed ration once a day. DM intake (DMI), milk yield, 4.0% fat-corrected milk (FCM), as well as protein concentration and yield were higher for WCS than ECS. Compared with WCS, cows tended to eat less with RCS, and produced less milk and milk protein. However, yield of FCM was similar between WCS and RCS. Milk fat concentration and yield, as well as the specific ratio of t11 18:1 to t10 18:1 in milk fat did not differ among diets. Milk urea-N tended to be higher for ECS than WCS and TS, whereas ruminal NH3-N was higher with ECS than TS. Rumen pH decreased linearly with time after feeding but was not different between treatments. Higher acetate and lower propionate concentration resulted in greater acetate to propionate ratio with ECS compared with WCS. In conclusion, removing grain fraction from CS decreased milk production and modified rumen fermentation without affecting milk fat concentration and yield. Moreover, despite some differences in DMI and total ruminal volatile fatty acid concentration between WCS and RCS, the restoration of FCM yield, using HMC in RCS diets, to a level of production similar to WCS highlights the importance of energy and nutrients supplied by the grain fraction of CS to support milk yield. PMID:23031720

Boivin, M; Gervais, R; Chouinard, P Y

2013-02-01

186

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

1951-01-01

187

The analysis of milk components and pathogenic bacteria isolated from bovine raw milk in Korea.  

PubMed

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, protein, and lactose). The associations between SCC or MUN and other milk components were investigated, as well as the relationships between the bacterial species isolated from milk. Somatic cell counts, MUN, and the percentages of milk fat, protein, and lactose were analyzed in 30,019 raw milk samples collected from 2003 to 2006. The regression coefficients of natural logarithmic-transformed SCC (SCCt) on milk fat (-0.0149), lactose (-0.8910), and MUN (-0.0096), and those of MUN on milk fat (-0.3125), protein (-0.8012), and SCCt (-0.0671) were negative, whereas the regression coefficient of SCCt on protein was positive (0.3023). When the data were categorized by the presence or absence of bacterial infection in raw milk, SCCt was negatively associated with milk fat (-0.0172), protein (-0.2693), and lactose (-0.4108). The SCCt values were significantly affected by bacterial species. In particular, 104 milk samples infected with Staphylococcus aureus had the highest SCCt (1.67) compared with milk containing other mastitis-causing bacteria: coagulase-negative staphylococci (n = 755, 1.50), coagulase-positive staphylococci (except Staphylococcus aureus; n = 77, 1.59), Streptococcus spp. (Streptococcus dysgalactiae, n = 37; Streptococcus uberis, n = 12, 0.83), Enterococcus spp. (n = 46, 1.04), Escherichia coli (n = 705, 1.56), Pseudomonas spp. (n = 456, 1.59), and yeast (n = 189, 1.52). These results show that high SCC and MUN negatively affect milk components and that a statistical approach associating SCC, MUN, and milk components by bacterial infection can explain the patterns among them. Bacterial species present in raw milk are an important influence on SCC in Korea. PMID:18024731

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

2007-12-01

188

Spectrophotometric determination of urea in sugar cane distilled spirits.  

PubMed

Urea is an important precursor in the formation of ethyl carbamate, a known carcinogen in alcoholic beverages. Ethyl carbamate has recently been detected at high concentrations in sugar cane distilled spirits, but little is known about the concentration of urea in these beverages. The objectives of this study were to validate methodology for the determination of urea in sugar cane distilled spirits, to determine the levels in 68 samples from different regions within the state of Minas Gerais, Brazil, and to examine the relationship between the concentrations of urea and ethyl carbamate. The method, based on the reaction of urea with 1-phenyl-1,2-propanodione-2-oxime and spectrophotometric quantification at 540 nm, provided linear response from 0.5 to 15.0 mg/L. No purification of the sample was required. The limits of detection and quantification were 0.1 and 0.5 mg/L, respectively. Urea was detected in 69% of the samples at levels varying from 0.50 to 5.10 mg/L. There was no significant difference on the levels of urea in samples from different regions of the state. No significant correlation between the levels of urea and ethyl carbamate was observed for the samples analyzed. PMID:18553892

Labanca, Renata A; Glória, M Beatriz A

2008-07-01

189

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. PMID:8514890

Effros, R M; Jacobs, E; Hacker, A; Ozker, K; Murphy, C

1993-01-01

190

An investigation of urea decomposition and selective non-catalytic removal of nitric oxide with urea  

E-print Network

of urea-water solution decomposition, for gas temperatures between 550 and 650 K, the highest concentrations were for NH3 and HNCO. On the other hand, the concentrations of CO2 were highest for gas temperatures of about 500 - 550 K. For temperatures above...

Park, Yong Hun

2004-09-30

191

Urea on Flaked Soybean Hulls as a Protein Replacement for Dairy Cows1  

Microsoft Academic Search

In Experiment I a Latin square design was used to study the utilization of urea nitrogen adsorbed on flaked soybean hulls in normal rations of high producing dairy cows. Concentrates containing urea, urea with supplemental minerals, or soybean meal as the protein supplement were fed with corn silage and alfalfa in a total ration of approximately 17% crude protein. Both

S. C. Peyton; H. R. Conrad

1978-01-01

192

Use of urea-molasses-multinutrient block and urea-treated rice straw for improving dairy cattle productivity in Vietnam.  

PubMed

After conducting a preliminary survey, a feeding trial was carried out to determine the effect of urea-molasses-multinutrient block (UMMB) and urea-treated rice straw (UTRS) as a feed supplement on the productivity of dairy cows. Sixty Holstein-Friesian crossbred cows on 11 smallholder farms were divided equally into control, UMMB and UTRS supplementation groups. Milk yield and feed intake were recorded daily. Milk fat content, body weight and body condition score (BSC) of each cow were determined at two week intervals. Milk samples for progesterone analysis were collected once a week commencing one month after parturition. Data were recorded for date of onset of ovarian activity, estrus, insemination, and conception rate. Milk production increased by 10.3-11.9% and milk fat content increased by 3-5%, therefore, profit for farmers increased by US $0.55-0.73 per cow per day (exchange rate US $1 = VN $11,000). The intervals from calving to onset of ovarian activity (91-94 days), to estrus (110-114 days), to conception (121-122 days) and the calving interval (13.4-13.6 months) in the trial groups were significantly shorter than those in the control group (112, 135, 152 days and 14.4 months, respectively. PMID:10081798

Vu, D D; Cuong, L X; Dung, C A; Hai, P H

1999-01-27

193

Milk Thistle  

MedlinePLUS

... 2005:467-482. Milk thistle. Natural Medicines Comprehensive Database. Accessed at www.naturaldatabase.com on October 7, 2009. Milk thistle ( Silybum marianum ), silymarin. Natural Standard Database Web site. Accessed at www.naturalstandard.com on ...

194

Milk Allergy  

MedlinePLUS

... 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 ...

195

Detecting multiple adulterants in dry milk using Raman chemical imaging  

NASA Astrophysics Data System (ADS)

This study investigated the potential of Raman chemical imaging for simultaneously detecting multiple adulterants in milk powder. Potential chemical adulterants, including ammonium sulfate, dicyandiamide, melamine, and urea, were together mixed into nonfat dry milk in the concentration range of 0.1%-5.0% for each adulterant. A benchtop point-scan Raman imaging system using a 785-nm laser was assembled to acquire hyperspectral images in the wavenumber range of 102-2538 cm-1. Each mixture was imaged in an area of 25×25 mm2 with a spatial resolution of 0.25 mm. Selfmodeling 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 visualize identification and spatial distribution of the multiple adulterant particles in the dry milk was demonstrated.

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

2012-05-01

196

Quantification of milk fat globule membrane proteins using selected reaction monitoring mass spectrometry.  

PubMed

Although some of the physiological roles of milk fat globule membrane (MFGM) proteins are still unclear, there is increasing evidence that the consumption of bovine MFGM proteins has significant nutritional health benefits for humans; therefore, it may be important to be able to estimate the MFGM proteins in complex ingredients. In this study, the absolute quantification (AQUA) technique, which is typically used for the quantification of proteins in proteomic studies, was applied for the quantification of bovine MFGM proteins in butter milk protein concentrate. Six MFGM proteins (fatty acid binding protein, butyrophilin, PAS 6/7, adipophilin, xanthine oxidase, and mucin 1) were simultaneously quantified using high-resolution selected reaction monitoring mass spectrometry. Samples were rehydrated in 6.7 M urea buffer prior to dilution to 2.2 M before tryspin digestion. Direct rehydration in 2.2 M urea buffer or 2.2 M urea/20% acetonitilrile buffer reduced peptide yield digestion. Isotopically labeled peptides were used as internal standards. The coefficient of variation ranged from 5 to 15%, with a recovery of 84-105%. The limit of detection was in the range of 20-40 pg. PMID:19537729

Fong, Bertram Y; Norris, Carmen S

2009-07-22

197

Microdetermination of urea in urine using p-dimethylaminobenzaldehyde /PDAB/  

NASA Technical Reports Server (NTRS)

Adaptation of the p-dimethylaminobenzaldehyde method for determining urea concentration in urine is an improved micromechanical method. Accuracy and precision are satisfactory. This method avoids extra steps of deproteinizing or removing normal urinary chromogens.

Geiger, P. J.

1969-01-01

198

Effect of dietary carbohydrate composition and availability on utilization of ruminal ammonia nitrogen for milk protein synthesis in dairy cows.  

PubMed

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

2003-07-01

199

Chemiresistor urea sensor  

DOEpatents

A sensor is disclosed 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. 16 figs.

Glass, R.S.

1997-12-16

200

Influences of dietary sucrose and urea on transfer of endogenous urea to the rumen of sheep and numbers of epithelial bacteria.  

PubMed

1. The rates of transfer of plasma urea to the rumen of six sheep given brome grass (Bromus inermis) pellets alone or with supplements of sucrose or urea were determined using [14C] urea and 14C-labelled sodium bicarbonate infusions during three periods. 2. The sheep were slaughtered after the third period and samples of rumen epithelium were taken for assessment of numbers of adherent bacteria. 3. Maximum transfer (0.31 g nitrogen/h) of urea ot the rumen was observed for sheep given supplements of 150 g sucrose/d plus 20 g urea/d. Maximum clearance of plasma urea to the rumen (rate of urea transfer to the rumen per unit plasma urea concentration, 5.8 1/h) was observed for sheep given 300 g sucrose/d. 4. Urea clearance to the rumen was negatively related to rumen ammonia concentration; the slope of the relationship was increased with each addition of sucrose to the diet. 5. Numbers of facultative bacteria adherent to the rumen epithelium were increased by urea and sucrose supplements. 6. The results are discussed in relation to a hypothesis which relates the ureolytic capability of the bacteria adherent to the rumen epithelium to the control of the rate of transfer of urea into the rumen. PMID:7317347

Kennedy, P M; Clarke, R T; Milligan, L P

1981-11-01

201

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

1996-01-01

202

Mannose-binding lectin 1 haplotypes influence serum MBL-A concentration, complement activity, and milk production traits in Chinese Holstein cattle.  

PubMed

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

2011-11-01

203

Sensitivity to Urea Fertilization in Three Amphibian Species L. K. Belden,2  

E-print Network

(Plethodon vehicu- lum, Rhyacotriton variegatus, and Taricha granulosa). In avoidance experiments, the three for T. granulosa at these concentrations. We suggest that environmental levels of urea could

Blaustein, Andrew R.

204

Effects of short-term supplementation of clinoptilolite in colostrum and milk on the concentration of some serum minerals in neonatal dairy calves.  

PubMed

In recent years, the use of both natural and synthetic zeolites in animal nutrition has increased mainly to improve their performance, health, and to protect against mycotoxin intoxication. Thirty calves were used in the present study for the determination of some physiologic effects of clinoptilolite supplementation. The animals were divided equally into three groups (control, test 1, and test 2). The three groups of calves were homogeneous for parity of dams, sex, and month of birth. For group test 1, clinoptilolite in the concentration of 2% of each colostrum meal was added for 48 h, and for group test 2, clinoptilolite in the concentration of 2% was added to each colostrum and milk meal for 14 days. Blood samples were taken from all calves 12 h after birth and at the end of the first, second, third, forth, fifth, and sixth weeks of life. Calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), sodium (Na), and potassium (K) were determined in the serum. For statistical analysis of data, a repeated measures approach using analysis of variance (ANOVA) with mixed linear models was used. Clinoptilolite supplementation had significant effect on the concentrations of calcium, phosphorus, sodium, and iron. The concentrations of Fe significantly higher in test group 2 than other trial groups (p < 0.05). Calcium concentrations were significantly higher in serum of clinoptilolite-treated than control calves (p < 0.05). The concentrations of phosphorus were significantly lower in test groups than control group (p < 0.05). Sodium concentrations were significantly higher in clinoptilolite-supplemented groups than control calves (p < 0.05). Potassium and magnesium concentrations were not affected by clinoptilolite supplementation. Clinoptilolite supplementation could promote iron levels in serum and better hemopoiesis and prevent pathologic or physiologic drop of red blood cell (RBC) parameters in supplemented calves during a first few weeks of life. According to higher need and utilization of Ca in growing animals, clinoptilolite supplementation could increase available Ca. Based on the results of the present study and the importance of dietary phosphorus in many physiologic processes, the level of phosphorus in diet of neonatal dairy calves must be considered and adapted when clinoptilolite was supplemented. With an adequate supply of good quality drinking water, cattle can tolerate large quantities of dietary sodium chloride. Thus, it seems that significant increase in serum Na concentration during short-term supplementation of clinoptilolite in neonatal calves could be well tolerated without any adverse effects. PMID:18317705

Mohri, M; Seifi, H A; Maleki, M

2008-01-01

205

Urea and ureolytic activity in lakes of different trophic status.  

PubMed

Urea and uraease (U-ase) activity were determined in water samples taken from the surface layers of 17 lakes of different trophic status. Urea concentrations were inversely correlated with the trophic status of the studied lakes and varied from below the detection limit to 25 micromol l(-1). Maximal potential ureolytic activity (V(max)) ranged from 0.2 to 7.0 micromol l(-1) h(-1). The highest urea concentrations and the lowest U-ase activities were recorded in the spring, whereas the lowest urea concentrations and the highest rates of urea hydrolysis were observed late in summer, during heavy phytoplankton blooms. Since in the majority of the Great Mazurian Lakes microplankton growth was limited by nitrogen supply, urea was an important N source for both auto- and heterotrophic planktonic microorganisms throughout the growth period. U-ase activity was mainly related to the seston. Only up to 25% of total activity could be attributed to free enzymes dissolved in lake water. In epilimnetic water samples the bulk of the ureolytic activity originated from seston-attached bacteria. However, a positive, statistically significant correlation between ureolytic activity and chlorophyll a (Chl(a)) concentrations suggests that phytoplankton may also be responsible for at least a some of the observed ureolytic activity in the highly eutrophic Great Mazurian Lakes. PMID:17338274

Siuda, Waldemar; Chróst, Ryszard J

2006-01-01

206

Evidence for urea-induced hypometabolism in isolated organs of dormant ectotherms.  

PubMed

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

2010-01-01

207

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

1958-01-01

208

Improving the nutritive value of wheat straw with urea and yeast culture for dry season feeding of dairy cows.  

PubMed

The study evaluated the effects of feeding urea treated/supplemented wheat straw-based diets with addition of yeast culture (YC) as a dry season feed for dairy cows. Wheat straw diets with 3.6% urea and 5.8% molasses were formulated to upgrade nonprotein nitrogen levels and fibre degradation in the rumen. Yeast culture was included at 0 and 10 g/cow/day in mixer with commercial dairy meal to improve on fibre degradation and milk yield. Two experiments were conducted. Firstly, an in sacco dry matter degradability (DMD) trial with three steers in a completely randomized design (CRD) with a 3?×?2 factorial arrangement to determine the effects on intake and rumen degradation parameters. Secondly, feeding trial with 18 lactating cows in a 3?×?2 factorial arrangement at two levels of yeast culture (0 and 10 g/cow/day) and three types of urea interventions: No intervention (WS); addition of urea to straw at the time of feeding (USWS); and 7 days incubation of straw with urea (UTWS). Yeast cultures addition had no effect on rumen pH and NH3-N, but urea intervention showed an effect on rumen pH with USWS being lowest (p?urea interventions and yeast culture addition had no effect (p?>?0.05) on dry matter intake, milk yield, and milk composition but they increased (p?

Kashongwe, Olivier Basole; Migwi, Preminius; Bebe, Bockline Omedo; Ooro, Patrick Auwor; Onyango, Tobias Atali; Osoo, John Odhiambo

2014-08-01

209

UREA LEVELS AND SUPPLEMENTAL ENERGY SOURCES IN SUGARCANE DIETS I  

Microsoft Academic Search

Two experiments, each involving a digestion-N balance trial and a feedlot trial, determined the replacement value of urea-corn meal (UC) for cottonseed meal (CSM) and the value of mo- lasses in sugarcane diets. Steers fed 70% sugarcane-30% concentrate diets with O, 28 or 56% of the dietary N as urea had a slight reduction (P<.28) in dry matter (DM) intake

F. M. Pate; P. M. Fairhurst; J. T. K. Munthali

210

Urea reduction of NO\\/sub x\\/ in combustion effluents  

Microsoft Academic Search

Method is claimed for reducing NO\\/sub x\\/ in combustion effluents by introducing urea at elevated temperatures in the presence of oxygen, either as a solid or solution in amounts sufficient to reduce the NO\\/sub x\\/ concentration. Conveniently, the urea may be introduced as a solid powder or as a solution in a hydroxylic solvent, at temperatures in excess of 1300°

J. K. Arand; L. J. Muzio; J. G. Sotter

1980-01-01

211

Structure and Dynamics of Urea/Water Mixtures Investigated by Vibrational Spectroscopy and Molecular Dynamics Simulation  

PubMed Central

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. Based on a variety of methods and of definitions of water structure, urea has been variously described as a structure-breaker, a structure-maker, or as remarkably neutral towards 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 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.

2013-01-01

212

Suckling reinitiated milk secretion in beef cows after an early postpartum hiatus of milking or suckling.  

PubMed

We determined whether milk secretion in beef cows could be reinitiated by renewed suckling after a hiatus from milking or suckling. Fifty-three Angus x Hereford cows were suckled ad libitum by their own calves for 13 to 18 d postpartum and then assigned to treatments for 4 wk in which cows were 1) neither milked nor suckled (weaned; n = 18), 2) milked 2 x daily (milked; n = 18), or 3) suckled by their own calves (suckled; n = 17). Thereafter, all calves (including earlier weaned calves) suckled their own dams until permanent weaning at 203 d of age, except when their dams were milked once after receiving (i.m.) 40 IU of oxytocin at reinitiation of suckling (0 wk) and again 1 and 5 wk later. Prolactin was increased in milked and suckled cows during 20 min after milking or suckling at the termination of treatments (0 wk). Concentrations of insulin-like growth factor-I were greater for weaned than suckled cows; milked cows had intermediate concentrations. At 0 wk, milk yield was greater for suckled than milked or weaned treatment cows. After 1 wk of renewed suckling, milk secretion of weaned treatment cows increased, and by 5 wk, composition of milk was normal, but yield was still reduced. We concluded that milk secretion was renewed by suckling in early postpartum cows after they were neither suckled nor milked for 4 wk. PMID:10416164

Lamb, G C; Miller, B L; Lynch, J M; Grieger, D M; Stevenson, J S; Lucy, M C

1999-07-01

213

Variation in milk cortisol during lactation in Murciano-Granadina goats.  

PubMed

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

2013-02-01

214

Milk thistle  

MedlinePLUS

Milk thistle is a plant. The above ground parts and seeds are used to make medicine. The seeds are more commonly used. Milk thistle is ... peppermint leaf, German chamomile, caraway, licorice, clown’s mustard plant, celandine, angelica, and lemon balm. When used daily ...

215

Designer milk.  

PubMed

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

2007-01-01

216

Trehalose protects urea-induced unfolding of ?-chymotrypsin.  

PubMed

Trehalose, a naturally occurring osmolyte, appears to be one of the most effective protectants for enzymes under various stress conditions while urea, a classical denaturant, destabilizes the activity, function, and alters the native structure of proteins. Herein, we have characterized the counteracting effects of trehalose on the deleterious effect of urea on ?-chymotrypsin (CT) through the calorimetric data (transition temperature (T(m)), enthalpy change (?H), heat capacity change (?C(p)) and Gibbs free energy of unfolding (?G(u)) by using differential scanning calorimeter (DSC) and circular dichroism (CD) techniques, respectively, at a 1:2 ratio of trehalose and urea, as well as various urea concentration (up to 6 M) in the presence of 1 M trehalose. Our parallel experimental results explicitly elucidate that trehalose strongly offset the deleterious actions of urea on CT at 1:2 molar ratio of trehalose and urea, however, trehalose (1 M) some how failed to counteract the perturbation effects of urea (3-6 M) on CT. PMID:20691724

Kumar, Awanish; Attri, Pankaj; Venkatesu, Pannuru

2010-11-01

217

Effects of decreasing metabolizable protein and rumen-undegradable protein on milk production and composition and blood metabolites of Holstein dairy cows in early lactation.  

PubMed

This study was conducted to evaluate the effects of decreasing dietary protein and rumen-undegradable protein (RUP) on production performance, nitrogen retention, and nutrient digestibility in high-producing Holstein cows in early lactation. Twelve multiparous Holstein lactating cows (2 lactations; 50 ± 7 d in milk; 47 kg/d of milk production) were used in a Latin square design with 4 treatments and 3 replicates (cows). Treatments 1 to 4 consisted of diets containing 18, 17.2, 16.4, and 15.6% crude protein (CP), respectively, with the 18% CP diet considered the control group. Rumen-degradable protein levels were constant across the treatments (approximately 10.9% on a dry matter basis), whereas RUP was gradually decreased. All diets were calculated to supply a postruminal Lys:Met ratio of about 3:1. Dietary CP had no significant effects on milk production or milk composition. In fact, 16.4% dietary CP compared with 18% dietary CP led to higher milk production; however, this effect was not significant. Feed intake was higher for 16.4% CP than for 18% CP (25.7 vs. 24.3 kg/d). Control cows had greater CP and RUP intakes, which resulted in higher concentrations of plasma urea nitrogen and milk urea nitrogen; cows receiving 16.4 and 15.6% CP, respectively, exhibited lower concentrations of milk urea nitrogen (15.2 and 15.1 vs. 17.3 mg/dL). The control diet had a significant effect on predicted urinary N. Higher CP digestibility was recorded for 18% CP compared with the other diets. Decreasing CP and RUP to 15.6 and 4.6% of dietary dry matter, respectively, had no negative effects on milk production or composition when the amounts of Lys and Met and the Lys:Met ratio were balanced. Furthermore, decreasing CP and RUP to 16.4 and 5.4%, respectively, increased dry matter intake. PMID:24679928

Bahrami-Yekdangi, H; Khorvash, M; Ghorbani, G R; Alikhani, M; Jahanian, R; Kamalian, E

2014-06-01

218

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

2012-05-01

219

Removal of milk fat globules from whey protein concentrate 34% to prepare clear and heat-stable protein dispersions.  

PubMed

Whey protein concentrates (WPC) are low-cost protein ingredients, but their application in transparent ready-to-drink beverages is limited due to turbidity caused by fat globules and heat instability. In this work, fat globules were removed from WPC 34% (WPC-34) to prepare heat-stable ingredients via the Maillard reaction. The removal of fat globules by acid precipitation and centrifugation was observed to be the most complete at pH 4.0, and the loss of protein was caused by micrometer-sized fat globules and protein aggregates. Spray-dried powder prepared from the transparent supernatant was glycated at 130°C for 20 and 30min or 60°C for 24 and 48h. The 2 groups of samples had comparable heat stability and degree of glycation, evaluated by free amino content and analytical ultracentrifugation, but high-temperature, short-time treatment reduced the color formation during glycation. Therefore, WPC-34 can be processed for application in transparent beverages. PMID:25108870

Liu, Gang; Zhong, Qixin

2014-10-01

220

Managing Milk Composition: Normal Sources of Variation  

E-print Network

Managing Milk Composition: Normal Sources of Variation Sandra R. Stokes, Dan N. Waldner, Ellen R. Jordan, and Michael L. Looper* Many factors influence the composition of milk, the major components of which are water, fat, protein, lactose... and minerals. Nutrition or dietary influences readily alter fat concentration and milk protein concentration. Fat concentration is the most sensitive to dietary changes and can vary over a range of nearly 3.0 percentage units. Dietary manipulation results...

Stokes, Sandra R.; Jordan, Ellen R.; Looper, Mike; Waldner, Dan

2000-12-11

221

Effect of protein concentration on the surface composition, water sorption and glass transition temperature of spray-dried skim milk powders  

Microsoft Academic Search

The effects of dilution of protein content in skim milk (34–8.5% protein content), by lactose addition, on the surface composition, water sorption property and glass transition temperatures of spray-dried powders were investigated. The X-ray photoelectron spectroscopy (XPS) study of spray-dried powders showed preferential migration of proteins toward the surface of the milk particles whereas the lactose remained in the bulk.

Ashok K. Shrestha; Tony Howes; Benu P. Adhikari; Barry J. Wood; Bhesh R. Bhandari

2007-01-01

222

Nutrient digestibility and protein utilization by heifers and steers fed high molasses-urea diets  

E-print Network

OF NITROGEN FROM DIFFERENT FEEDS CONSUMED BY STEERS FED THREE LEVELS OF FISH MEAL. 34, Viii Table 12 Appendix Table NITROGEN BALANCE OF STEERS FED THREE LEVELS OF FISH MEAL WITH HIGH MOLASSES-UREA DIETS. . . . . . . . BLOOD UREA CONCENTRATION, RUMEN.... Blood urea concentrations are presented in Table 12. 36 TABLE 11. NITROGEN BALANCE OF STEERS FED THREE LEVELS OF I FISH MEAL WITH HIGH MOLASSES-UREA DIETS' Fish meal level, g/100. kg body weight. 80 120 180 ~Steer 2 N intake, g N output, gs...

Pina, Angel Modesto

2012-06-07

223

The effect of feeding human milk and adapted milk formulae on serum lipid and lipoprotein levels in young infants  

Microsoft Academic Search

The effect of feeding with human milk and commercially available milk substitutes was studied in a group of 154 healthy infants during the first 3 months of life by assessment of body weight, body length, head circumference, skinfold thickness, serum lipid and lipoprotein concentrations. Human milk and the different milk formulae have the same energy content (kcal\\/100 ml) and total

V. Wagner; H. B. von Stockhausen

1988-01-01

224

SEDIMENTATION FIELD-FLOW FRACTIONATION AS A TOOL FOR THE STUDY OF MILK PROTEIN-STABILIZED MODEL OIL-IN-WATER EMULSIONS: EFFECT OF PROTEIN CONCENTRATION AND HOMOGENIZATION PRESSURE  

Microsoft Academic Search

Milk protein-stabilized model emulsions were formed using high-pressure homogenization and the effect of protein concentration and homogenization pressure during emulsification on the particle size was studied. Various techniques are available for determining particle size distribution, each one of which has its own advantages and disadvantages. In this study sedimentation field-flow fractionation was employed for the size characterization of oil-in water

Stella Kenta; Vassilios Raikos; John Kapolos; Athanasia Koliadima; George Karaiskakis

2012-01-01

225

Urea: An important piece of Water Soluble Organic Nitrogen (WSON) over the Eastern Mediterranean.  

PubMed

The role of atmospheric urea on the biogeochemical cycle of Water Soluble Organic Nitrogen (WSON) in the Eastern Mediterranean was assessed by collecting and analyzing wet and dry deposition samples and size segregated aerosols during a one year period (2006). In rain water volume weighted mean (VWM) concentration of urea was found equal to 5.5?M. In atmospheric particles the average concentration of urea in coarse and fine mode was 0.9±1.9nmol N m(-3) (median 0.0nmol N m(-3)) and 2.2±3.0nmol N m(-3) (median 1.1nmol N m(-3)), respectively. The percentage contribution of urea to WSON fraction was 0% and 20% in coarse and fine particles respectively. On an annual basis 0.81mmol m(-2) and 1.78mmol m(-2) of urea were deposited via wet and dry deposition, contributing to WSON by 10% and 11% respectively. Regression analysis of urea with the main ions and trace metals measured in parallel suggest that soil and anthropogenic activities significantly contribute to atmospheric urea. Comparison of dry deposition of urea using size segregated deposition velocities with urea collected on a glass bead collector suggested the existence of significant fraction of urea in the gas phase. PMID:21903240

Violaki, Kalliopi; Mihalopoulos, Nikos

2011-10-15

226

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

227

Transfer of urea from the blood to the rumen of sheep.  

PubMed

1. The rate of transfer of plasma urea-nitrogen to rumen ammonia was measured by infusion of 15NH4Cl and [15N]urea into sheep given brome grass (Bromus inermis) or lucerne (Medicago sativa) pellets. Urea was infused into the rumen or abomasum of two sheep given brome grass in order to increase the concentration of rumen ammonia. 2. From 6.2 to 9.8 g/d of plasma urea-N were transferred to the rumen of sheep given brome grass pellets and a measurement of 1.3 g nitrogen/d was obtained for a sheep given lucerne pellets. When urea was infused into the rumen of sheep given brome grass pellets the transfer was only 2.8--3.7 g N/d. 3. There was a significant negative correlation between the rate of transfer of plasma urea-N to the rumen and the concentration of rumen ammonia. PMID:666998

Kennedy, P M; Milligan, L P

1978-07-01

228

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.  

PubMed

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

2013-08-01

229

Effect of milk fat globule membranes on emulsion stability of recombined sterilized milk  

E-print Network

Recombined oil-in-water emulsions containing 3% protein and 3% milk fat were prepared from low-heat nonfat dry milk, whey protein concentrate and anhydrous milk fat. The effect of casein to whey protein ratios of 80:20, 60:40, 40:60 and 0...

Hernandez, Gabriela Perez

2012-06-07

230

Effects of fertilizer-urea on growth, photosynthetic activity and microcystins production of Microcystis aeruginosa isolated from Dianchi Lake.  

PubMed

Urea is the most frequently applied nitrogen (N) fertilizer in agriculture, while its loss is assumed triggering algal blooms in adjacent water bodies. In this context the present study assessed the growth, photosynthetic activity as well as toxin production of Microcystis aeruginosa at different urea concentrations (0.125, 1.25, 12.5, 250 and 2,500 mg/L) using BG11 (containing 250 mg/L NO3(-)-N) as control. The results showed for all endpoints that M. aeruginosa is capable of using urea as N source: the two highest urea treatments delivered comparable values like the control. Low urea concentrations (0.125 and 1.25 mg/L), which were comparable to environmental urea levels, did not sustainably promote the growth, photosynthesis and toxin production of the test species. While, in certain microenvironments urea might potentially reach the concentrations that may affect M. aeruginosa. PMID:24515350

Huang, Wenmin; Bi, Yonghong; Hu, Zhengyu

2014-05-01

231

Milk Allergy in Infants  

MedlinePLUS

... Milk Allergy Unsafe Formulas Switching Formulas About Milk Allergy Almost all infants are fussy at times. But ... kids and adults. Continue Symptoms of a Milk Allergy Symptoms of cow's milk protein allergy will generally ...

232

Pumping and Milk Storage  

MedlinePLUS

... information in Spanish ( en español ) Pumping and milk storage Pumping Storage of breast milk More information on ... and letting it air dry. Return to top Storage of breast milk Breast milk can be stored ...

233

NiO nanoparticle-based urea biosensor.  

PubMed

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

2013-03-15

234

Urea secretion by the straight segment of the proximal tubule.  

PubMed Central

Studies utilizing in vitro microperfusion were designed to examine whether urea is actively or passively transported across superficial and juxtamedullary straight segments of rabbit proximal tubules. With perfusate and bath solutions containing 1 mM urea and electrolytes similar to normal plasma, the efflux (lumen-to-bath) isotopic permeability (X 10(-5) cm s-1) of superficial segments was 1.37 +/- 0.16 and of juxtamedullary segments was 2.14 +/- 0.20. In the same tubules, the influx (bath-to-lumen) isotopic permeability was 3.70 +/- 0.35 in superficial segments and 4.75 +/- 0.37 in juxtamedullary segments. Despite net water movement in the opposite direction (0.5 nl mm-1 min-1), the influx rate was significantly higher than the efflux rate of urea in both groups. With a low perfusion rate (2 nl/min) and equivalent specific activities of [14C]urea in bath and perfusate, the collected-to-perfused ratio of [14C]urea, corrected for volume marker change, was 1.07 +/- 0.01 in superficial and 1.09 +/- 0.01 in juxtamedullary nephrons, thus indicating net secretion in both segments. In separate studies urea influx was inhibited by hypothermia (decrease from 37 degrees to 28 degrees C), by phloretin (0.1 mM in bath), by cyanide (1 mM), but not by probenecid (0.2 mM). In each case the inhibition was highly significant and reversible. These data suggest that urea is actively secreted by the straight segments of both the superficial and juxtamedullary proximal tubules. These segments may, therefore, contribute significantly to the high urea concentration found at the bend of Henle's loop by micropuncture. PMID:956389

Kawamura, S; Kokko, J P

1976-01-01

235

Concentration  

NSDL National Science Digital Library

Watch your solution change color as you mix chemicals with water. Then check molarity with the concentration meter. What are all the ways you can change the concentration of your solution? Switch solutes to compare different chemicals and find out how concentrated you can go before you hit saturation!

Simulations, Phet I.; Chamberlain, Julia; Malley, Chris; Lancaster, Kelly; Moore, Emily B.; Perkins, Kathy

2012-03-09

236

Distinct cellular pathways for resistance to urea stress and hypertonic stress.  

PubMed

During antidiuresis with elevated vasopressin, urea accumulates in the renal medulla to very high concentrations, imposing considerable cellular stress. How local cells cope with urea stress is relevant to the whole kidney because the renal medulla is the major site of residence for the renal stem cells. Previous studies showed that renal cells were incapable of preconditioning in moderate urea concentrations to enhance resistance to urea stress. Instead, preconditioning in moderately high salinity (moderate hypertonicity) has been shown to promote resistance to urea stress due to the induction of the molecular chaperone heat shock protein 70 (Hsp70), which is mediated by the transcription factor tonicity-responsive enhancer binding protein (TonEBP). Here we report that cell lines derived from the kidney and fibroblasts display enhanced resistance to urea stress after pretreatment in moderate, nonstressful concentrations of urea. Using TonEBP knockdown and immunoblot analyses, we demonstrate that TonEBP and Hsp70 are dispensable for the increased resistance to urea stress. These data suggest that cells in the renal medulla are capable of overcoming urea stress by activating distinct cellular pathways. PMID:21178107

Lee, Sang Do; Choi, Soo Youn; Kwon, H Moo

2011-03-01

237

Influence of Condensed Tannins from Ficus bengalensis Leaves on Feed Utilization, Milk Production and Antioxidant Status of Crossbred Cows.  

PubMed

This study was conducted to examine the effects of condensed tannins (CT) from Ficus bengalensis leaves on the feed utilization, milk production and health status of crossbred cows. Eighteen crossbred dairy cows at their second and mid lactation (avg. BW 351.6±10.6 kg) were randomly divided into two groups of nine each in a completely randomized block design and fed two iso-nitrogenous supplements formulated to contain 0% and 1.5% CT through dried and ground leaves of Ficus bengalensis. The diets were designated as CON and FBLM, respectively and fed to cows with a basal diet of rice straw to meet requirements for maintenance and milk production. The daily milk yield was significantly (p<0.05) increased due to supplementation of FBLM diet. The 4% fat corrected milk yield was also significantly (p<0.01) higher due to increased (p<0.05) milk fat in cows under diet FBLM as compared to CON. The inclusion of CT at 1.5% in the supplement did not interfere with the feed intake or digestibility of DM, OM, CP, EE, NDF, and ADF by lactating cows. Digestible crude protein (DCP) and total digestible nutrients (TDN) values of the composite diets were comparable between the groups. The blood biochemical parameters remained unaltered except significantly (p<0.05) lowered serum urea concentration in cows fed FBLM diet. There was a significant (p<0.05) increase intracellular reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activity in cows supplemented with condensed tannins. The total thiol group (T-SH) was found to be higher with reduction in lipid peroxidation (LPO) in cows of FBLM group. The cost of feeding per kg milk production was also reduced due to supplementation of Ficus bengalensis leaves. Therefore, a perceptible positive impact was evident on milk production and antioxidant status in crossbred cows during mid-lactation given supplement containing 1.5% CT through Ficus bengalensis leaves. PMID:25049960

Dey, Avijit; De, Partha Sarathi

2014-03-01

238

Influence of Condensed Tannins from Ficus bengalensis Leaves on Feed Utilization, Milk Production and Antioxidant Status of Crossbred Cows  

PubMed Central

This study was conducted to examine the effects of condensed tannins (CT) from Ficus bengalensis leaves on the feed utilization, milk production and health status of crossbred cows. Eighteen crossbred dairy cows at their second and mid lactation (avg. BW 351.6±10.6 kg) were randomly divided into two groups of nine each in a completely randomized block design and fed two iso-nitrogenous supplements formulated to contain 0% and 1.5% CT through dried and ground leaves of Ficus bengalensis. The diets were designated as CON and FBLM, respectively and fed to cows with a basal diet of rice straw to meet requirements for maintenance and milk production. The daily milk yield was significantly (p<0.05) increased due to supplementation of FBLM diet. The 4% fat corrected milk yield was also significantly (p<0.01) higher due to increased (p<0.05) milk fat in cows under diet FBLM as compared to CON. The inclusion of CT at 1.5% in the supplement did not interfere with the feed intake or digestibility of DM, OM, CP, EE, NDF, and ADF by lactating cows. Digestible crude protein (DCP) and total digestible nutrients (TDN) values of the composite diets were comparable between the groups. The blood biochemical parameters remained unaltered except significantly (p<0.05) lowered serum urea concentration in cows fed FBLM diet. There was a significant (p<0.05) increase intracellular reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activity in cows supplemented with condensed tannins. The total thiol group (T-SH) was found to be higher with reduction in lipid peroxidation (LPO) in cows of FBLM group. The cost of feeding per kg milk production was also reduced due to supplementation of Ficus bengalensis leaves. Therefore, a perceptible positive impact was evident on milk production and antioxidant status in crossbred cows during mid-lactation given supplement containing 1.5% CT through Ficus bengalensis leaves. PMID:25049960

Dey, Avijit; De, Partha Sarathi

2014-01-01

239

Nutritional adequacy of goat milk infant formulas for term infants: a double-blind randomised controlled trial.  

PubMed

The safety and nutritional adequacy of goat milk infant formulas have been questioned. The primary aim of the present study was to compare the growth and nutritional status of infants fed a goat milk infant formula with those of infants fed a typical whey-based cow milk infant formula. The secondary aim was to examine a range of health- and allergy-related outcomes. A double-blind, randomised controlled trial with 200 formula-fed term infants randomly assigned to receive either goat or cow milk formula from 2 weeks to at least 4 months of age was conducted. A cohort of 101 breast-fed infants was included for comparison. Weight, length and head circumference were measured at 2 weeks and 1, 2, 3, 4, 6 and 12 months of age. Nutritional status was assessed from serum albumin, urea, creatinine, Hb, ferritin, and folate and plasma amino acid concentrations at 4 months. Z-scores for weight, length, head circumference and weight for length were not different between the two formula-fed groups. There were differences in the values of some amino acids and blood biomarkers between the formula-fed groups, but the mean values for biomarkers were within the normal reference range. There were no differences in the occurrence of serious adverse events, general health, and incidence of dermatitis or medically diagnosed food allergy. The incidence of parentally reported blood-stained stools was higher in the goat milk formula-fed group, although this was a secondary outcome and its importance is unclear. Goat milk formula provided growth and nutritional outcomes in infants that did not differ from those provided by a standard whey-based cow milk formula. PMID:24502951

Zhou, Shao J; Sullivan, Thomas; Gibson, Robert A; Lönnerdal, Bo; Prosser, Colin G; Lowry, Dianne J; Makrides, Maria

2014-05-01

240

Lysozyme Transgenic Goats' Milk Influences Gastrointestinal Morphology in Young Pigs1,2  

Microsoft Academic Search

Transgenesis provides a method of expressing novel proteins in milk to increase the functional benefits of milk consumption. Transgenic goats expressing human lysozyme (hLZ) at 67% of the concentration in human breast milk were produced, thereby enhancing the antimicrobial properties of goats' milk. The objective of this study was to investigate the impact of pasteurized milk containing hLZ on growth,

Dottie R. Brundige; Elizabeth A. Maga; Kirk C. Klasing; James D. Murray

241

Milk osmolality: does it matter?  

PubMed

High osmolality of infant feed reflects a high concentration of solute particles and has been implicated as a cause of necrotising enterocolitis. Evidence for direct intestinal mucosal injury as a result of hyperosmolar feeds is scant, and no good evidence has been found to support such an association. High osmolality of enteral substrate may, however, slow down gastric emptying. Osmolality of current infant feeds ranges from around 300 mOsm/kg in human breast milk to just more than 400 mOsm/kg in fully fortified breast milk. Addition of mineral and vitamin supplements to small volumes of milk can increase osmolality significantly and should be avoided if possible. PMID:21930688

Pearson, Freya; Johnson, Mark J; Leaf, Alison A

2013-03-01

242

Benefits of different urea supplementation methods on the production performances of Merino sheep.  

PubMed

The impact of urea supplementation of sheep feed was examined in two experiments. In Experiment 1, 48 8-month-old Merino wethers were randomised into three groups by liveweight and each group was fed one of three diets: (1) untreated oaten chaff hay; (2) hay treated with urea in-paddock (pre-experiment); or (3) hay treated with a 2% urea solution using a feed mixer. In Experiment 2, 48 4-month-old Merino ewes were randomised into three groups and each group received one of the following roughages: (1) untreated oaten chaff hay, (2) hay treated with a 2% urea solution in a feed mixer, or (3) a 20?kg urea lick block. Both experiments lasted 40 days, and sheep liveweight (kg), average feed intake (g/day), average daily gain (ADG) and body condition score (BCS) were recorded. Ruminal fluid and blood samples were collected on days 20 and 40 from animals in Experiment 1. Sheep supplemented with additional urea had a greater average dry matter (DM) intake (Experiment 1, P?=?0.038; Experiment 2, P?=?0.001), ADG (Experiment 1, P?=?0.043; Experiment 2, P?=?0.041) and average final liveweight (Experiment 1, P?=?0.048), compared to sheep receiving no additional supplementary urea. On both days 20 and 40 in Experiment 1, blood analyses revealed that urea supplemented sheep had elevated levels of urea, creatine kinase and total protein (P?<0.05). Urea supplementation most likely influenced blood urea and total protein concentrations, as supplemented sheep had an increased crude protein intake (through increased feed intake of urea treated roughage with a higher crude protein percentage). By providing additional urea, the DM intake of sheep in both experiments was increased and offers a practical strategy when providing supplementation to sheep. The practice can benefit sheep production by increasing the nutritional value and digestibility of low energy crop stubbles, when fed over dry summer months to help maintain BCS. PMID:24792451

Sweeny, Joshua P A; Surridge, Victoria; Humphry, Pia S; Pugh, Harriet; Mamo, Kristen

2014-06-01

243

Total arsenic in rice milk.  

PubMed

Rice milk and its by-products were tested for total arsenic concentration. Total arsenic concentration was determined using graphite-furnace atomic absorption spectrometry. The arsenic concentrations ranged from 2.7 ± 0.3 to 17.9 ± 0.5 µg L(-1). Rice milk and its by-products are not clearly defined as food, water or milk substitute. The US Environmental Protection Agency (EPA), the European Union (EU) and the World Health Organization (WHO) have set a level of 10 µg L(-1) for total arsenic concentrations in drinking water. The EU and the US regulatory agencies do not provide any guidelines on total arsenic concentrations in foods. This study provides us with a starting point to address this issue in the State of Mississippi, USA. PMID:24779982

Shannon, Ron; Rodriguez, Jose M

2014-03-01

244

Effects of feeding lauric acid or coconut oil on ruminal protozoa numbers, fermentation pattern, digestion, omasal nutrient flow, and milk production in dairy cows.  

PubMed

The objectives of this study were to evaluate the feeding of coconut oil (CO), in which lauric acid (La) comprises about 50% of the fatty acid composition, as a practical rumen protozoa (RP) suppressing agent, to assess whether the source of La affects ruminal fermentation and animal performance and to test whether suppressing RP improves N utilization, nutrient digestion, nutrient flow at the omasal canal, and milk production. Fifteen multiparous Holstein cows (3 fitted with ruminal cannulas) and 15 primiparous Holstein cows (3 fitted with ruminal cannulas) were used in a replicated 3×3 Latin square experiment with 14d of adaptation and 14d of sample collection. Diets were fed as total mixed ration and contained (dry matter basis) 10% corn silage, 50% alfalfa silage, and 40% concentrate. The control diet contained 3% (dry matter basis) calcium soaps of palm oil fatty acids (Megalac, Church & Dwight Co. Inc., Princeton, NJ) as a ruminally inert fat source and had no added La or CO. Diets with La and CO were formulated to contain equal amounts of La (1.3%, dry matter basis). Dry matter intake was not affected by treatment. Both CO and La reduced RP numbers by about 40%. Lauric acid reduced yield of milk and milk components; however, CO did not affect yield of milk and yields of milk components. Both La and CO caused small reductions in total VFA concentration; CO increased molar proportion of ruminal propionate, reduced ruminal ammonia and branched-chain volatile fatty acids, suggesting reduced protein degradation, and reduced milk urea N and blood urea N concentrations, suggesting improved protein efficiency. Lauric acid reduced total-tract apparent digestibility of neutral detergent fiber and acid detergent fiber as well as ruminal apparent digestibility of neutral detergent fiber and acid detergent fiber as measured at the omasal canal; however, CO did not alter fiber digestion. Microbial protein flow at the omasal canal, as well as the flow of N fractions at the omasal canal, did not differ among treatments. Results from this experiment have confirmed that dietary La is not a practical agent for suppressing RP population in dairy cows, mainly because of its negative effects on fiber digestion and ruminal fermentation. Intake of CO appeared to reduce ruminal and improve protein efficiency, but did not improve milk production, milk composition, or increase microbial outflow from the rumen. Based on the results of this study, a 40% reduction of RP population is not sufficient to improve N utilization in dairy cows. PMID:24931520

Faciola, A P; Broderick, G A

2014-08-01

245

Milk metabolites as indicators of mammary gland functions and milk quality.  

PubMed

The assumption, that metabolites derived from the activity of the mammary gland epithelial cells reflect changes in milk secretion and its coagulation properties, was tested in dairy cows. The experiment included cows with uninfected udders and cows with one of the glands infected by different bacteria specie. Analysis were carried at the cow level (including all four glands), or at the gland level. High and significant correlations among the concentrations of lactose, glucose, glucose-6-posphate, milk related respiratory index (the ratio between the concentrations of citrate/lactate+malate in milk) and milk-derived glycolytic index (the ratio between glucose-6-phosphate and glucose in milk) and milk clotting parameters were found. The physiological basis for these relations and their ability to predict the deterioration in milk quality in subclinically infected glands and in glands previously clinically infected with Escherichia coli are discussed. PMID:25052436

Silanikove, Nissim; Merin, Uzi; Shapiro, Fira; Leitner, Gabriel

2014-08-01

246

Breast milk retinol and plasma retinol-binding protein concentrations provide similar estimates of vitamin A deficiency prevalence and identify similar risk groups among women in Cameroon but breast milk retinol underestimates the prevalence of deficiency among young children.  

PubMed

Breast milk vitamin A (BMVA) has been proposed as an indicator of population vitamin A status but has rarely been applied in large-scale surveys or compared with conventional vitamin A biomarkers. We assessed the prevalence of, and risk factors for, low BMVA and its relation to vitamin A intake, plasma retinol-binding protein (pRBP), and markers of inflammation in a national survey in Cameroon. We randomly selected 30 clusters in each of 3 strata (South, North, and Cities). Casual milk samples were collected from approximately 5 women per cluster (n = 440). pRBP, plasma C-reactive protein (pCRP), plasma ?1-acid glycoprotein (pAGP), and 24-h vitamin A intake were assessed in 10 women aged 15-49 y and 10 children aged 12-59 mo per cluster, including a subset of lactating women (n = 253). Low BMVA was infrequent: 7.2% (95% CI: 4.7, 9.8) of values were <1.05 ?mol/L, and 9.3% (95% CI: 5.8, 12.7) were <8 ?g/g fat, consistent with the low prevalence of pRBP <0.78 ?mol/L among women (< 5%) but lower than the prevalence of pRBP <0.83 ?mol/L among children (35%). Risk factors for both low BMVA and pRBP included living in the North and low maternal education. BMVA was positively associated with inflammation-adjusted pRBP among women in the lowest vitamin A intake tertile [<115 ?g retinol activity equivalents (RAEs)/d, P < 0.01] but not in the highest tertile (>644 ?g RAEs/d, P > 0.4). Controlling for milk fat, BMVA was negatively associated with pCRP (P < 0.02) but not pAGP (P > 0.5). BMVA and pRBP provide similar estimates of vitamin A deficiency prevalence and identify the same risk groups among women in Cameroon, but BMVA underestimates the prevalence of vitamin A deficiency among young children. PMID:24336458

Engle-Stone, Reina; Haskell, Marjorie J; Nankap, Martin; Ndjebayi, Alex O; Brown, Kenneth H

2014-02-01

247

[Determination of aflatoxins in milk and milk products (author's transl)].  

PubMed

During the period from September 1972 till December 1974 260 samples of milk, 41 of milk powder, 54 of yoghurt, 80 of fresh cheese, 65 of camembert, 77 of hard cheese and 134 of processed cheese were investigated for their contents of aflatoxin B1, B2, G1, G2, and M1. In all products containing toxin only aflatoxin M1 could be detected. The average values of aflatoxin M1 concentration during the period of investigation amounted to: 0.07 microng/1 for milk, 0.50 microng/kg for milk powder, 0.20 microng/kg for yoghurt, 0.23 microng/kg for fresh cheese, 0.43 microng/kg for hard cheese, 0.26 microng/kg for processed cheese, and 0.31 microng/kg for camembert. As maximum values the following concentrations were found: milk 0.33 microng/1, milk powder 2.0 microng/kg, yoghurt 0.47 microng/kg, fresh cheese 0.51 microng/kg, camembert 0.73 microng/kg, hard cheese 1.3 microng/kg, and processed cheese 0.55 microng/kg. PMID:857494

Polzhofer, K

1977-03-21

248

Urea retention and uptake by avocado and apple leaves  

Microsoft Academic Search

Solution retention by avocado (Persea americana cv. Fuerte) and apple (Mallus domestica Burkh. cv. Anna) leaves was measured by weight gain of detached leaves after dipping them in solutions of two surfactants and by analysis of various concentrations of urea retained at zero time on surfaces of attached leaves. Linear regression equations were calulated, relating leaf area and retention of

Isaac Klein; Shmuel Zilkah

1986-01-01

249

Serum total and free tryptophan levels in term infants fed cow's milk formula or human milk  

Microsoft Academic Search

We found no significant differences in mean total and free tryptophan concentrations in sera of healthy, full-term infants fed cow's milk formula and healthy, full-term infants who were breast-fed. Serum tryptophan concentrations were measured 1 h after feeding when the infants were 2 and 6 days of age. In this study cow's milk formula compared favourably with human milk as

V. Zanardo; M. D'Aquino; L. Stocchero; M. Biasiolo; G. Allegri

1989-01-01

250

Urea Biosynthesis Using Liver Slices  

ERIC Educational Resources Information Center

Presented is a practical scheme to enable introductory biology students to investigate the mechanism by which urea is synthesized in the liver. The tissue-slice technique is discussed, and methods for the quantitative analysis of metabolites are presented. (Author/SL)

Teal, A. R.

1976-01-01

251

Concentration  

NSDL National Science Digital Library

This NCTM iOS app of the familiar online Illuminations game, "Concentration" (cataloged separately) challenges a user to match whole numbers, shapes, fractions, or multiplication facts to equivalent representations. This game can be played by one or two players taking turns and can be played in clear pane mode, or for added challenge, with the windows closed.

2011-09-15

252

Concentration  

NSDL National Science Digital Library

This is the NCTM Android app of their familiar on line Illuminations game, "Concentration" ( cataloged separately ) which challenges a user to match whole numbers, shapes, fractions, or multiplication facts to equivalent representations. This game can be played by one or two players taking turns and can be played in clear pane mode, or for added challenge, with the windows closed.

2011-08-11

253

Sensitivity to urea fertilization in three amphibian species.  

PubMed

Forest fertilization with granular urea is a well-established management practice in many forested regions of the world. We hypothesize that chemical forest fertilizers may be affecting forest-dwelling wildlife. In the laboratory, we studied the effects of fertilization doses of granular urea on three species of forest-dwelling amphibians (Plethodon vehiculum, Rhyacotriton variegatus, and Taricha granulosa). In avoidance experiments, the three species avoided a substrate treated with a dose of 225 kg N/ha urea. In toxicity experiments, we exposed amphibians to urea at doses of 225 kg N/ha and 450 kg N/ha for 4 days. The observed effects increased with time and dose, and there were significant differences in sensitivity among the species. Both treatment levels had an acute effect on survival of P. vehiculum and R. variegatus. At 24 h, mortality at the highest dose was 67% for P. vehiculum, and 47% for R. variegatus. In contrast, there was no mortality for T. granulosa at these concentrations. We suggest that environmental levels of urea could be affecting behavior and survival of some amphibians species in fertilized forests. PMID:11443373

Marco, A; Cash, D; Belden, L K; Blaustein, A R

2001-04-01

254

Application of Individualized Bayesian Urea Kinetic Modeling to pediatric hemodialysis.  

PubMed

Incorporating urea rebound using equilibrated urea concentration (Ceq) after hemodialysis (HD) is essential for accurate assessment of HD efficiency. It is impractical to measure Ceq in clinical settings, and there are no recommended methodologies to predict Ceq in children. The objective of this work is to assess the ability of an Individualized Bayesian Urea Kinetic Model (IBKM) for predicting Ceq in children receiving HD. Developed based on adult HD data, the IBKM is a two-pool urea kinetic model that calculates Bayesian estimates of individual Ceq. Blood urea nitrogen (BUN) samples from 30 HD sessions in 13 children (age 12-18 years) were taken at pre-HD, immediately post-HD, and 60 minutes post-HD (Ceq). The IBKM and estimated population parameters from adult data were fitted to the observed data from children to predict individual Ceq using NONMEM VI software in comparison with observed Ceq (9.5 +/- 3.8 mmol/L), the average individual predicted Ceq was 9.4 +/- 3.8 mmol/L, with absolute individual prediction error of 6.2% +/- 4.4%. For a given dialysis goal and desired dialysis duration, the required blood flow rate and dialyzer size are predicted by IBKM and confirmed by the analysis data. This study suggests that the IBKM can be used in a pediatric HD setting and accurately predict Ceq in children using only pre-HD and immediately post-HD BUN. PMID:20168209

Marsenic, Olivera; Zhang, Liping; Zuppa, Athena; Barrett, Jeffrey S; Pfister, Marc

2010-01-01

255

Short Communication: The Effect of Duodenal Ammonia Infusions on Milk Production and Nitrogen Balance of the Dairy Cow  

Microsoft Academic Search

We hypothesized that an increased uptake of ammo- nia from the gut of dairy cows would increase the use of amino acids for urea synthesis and decrease the avail- ability of amino acids for milk protein production, lead- ing to a reduction in milk protein output. To test this hypothesis, four multiparous Holstein-Friesian dairy cows offered a constant diet based

J. M. Moorby; V. J. Theobald

1999-01-01

256

Influence of genetic variant for ?S1 casein and diet nitrogen content on milk production characteristics, and plasma  

E-print Network

among variants. Blood glucose was reduced in AA variants all along the trial. Increasing CP content ; EE : H, M, and L ; FF : B, H, and M. Milk production and DM intake (measured on 3 days), fat, protein, lactose, urea and ash content of milk were recorded each wk from wk 1 to 15 of the trial. Plasma glucose

Paris-Sud XI, Université de

257

Relative efficiency of prilled urea and urea-supergranules in Java citronella ( Cymbopogon winterianus Jowitt)  

Microsoft Academic Search

A two-year field study was carried out to compare the efficiency of prilled urea and urea-supergranules in the cultivation of a perennial aromatic grass, citronella (Cymbopogon winterianus Jowitt) in a sandy loam soil. Application of 300kg Nha-1 year-1 increased the herb and essential oil yields. Urea-supergranules significantly increased the yields over prilled urea.

EVS Prakasa Rao; Munnu Singh; Narayana; G Chandrasekhara

1984-01-01

258

Effects of adding urea on fermentation quality of pruned persimmon branch silage and its digestibility, preference, nitrogen balance and rumen fermentation in beef cattle.  

PubMed

Four cattle were used in a 4?×?4 Latin square design experiment to study digestibility, ruminal fermentation, nitrogen retention and preference of ensiling pruned persimmon branch (PPB) chips treated with urea. After 60 days of ensiling, urea-treated PPB showed higher (P?urea PPB. Both urea-treated PPB and rice straw diets showed higher (P?urea PPB diet. Neither mold nor yeast was detected in any urea-treated PPB. Urinary and fecal excretion as well as nitrogen retention in cattle fed urea-treated PPB were higher (P?urea PPB and rice straw. With the exception that ruminal ammonia-N levels in cattle fed urea-treated PPB were higher (P?urea PPB and rice straw, ruminal pH, volatile fatty acid concentrations, and the acetic?:?propionic acid ratio of rumen content were unaffected by diets. The rank order of preference was rice straw?>?low-urea?>?no-urea?>?high-urea. The results suggested that urea treatment of PPB inhibited growth of mold and yeast during silage storage, enhanced its digestibility and had nutritive value almost equivalent to that of rice straw. PMID:24131432

Cao, Yang; Zang, Yanqing; Lv, Renlong; Takahashi, Toshiyoshi; Yoshida, Norio; Yang, Huanmin

2014-03-01

259

40 CFR 721.9892 - Alkylated urea.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Alkylated urea. 721.9892 Section 721.9892 ...Chemical Substances § 721.9892 Alkylated urea. (a) Chemical substance and significant...substance identified generically as an alkylated urea (PMN P-93-1649) is subject to...

2010-07-01

260

FITC-tagged macromolecule-based alginate microspheres for urea sensoring  

NASA Astrophysics Data System (ADS)

Urea is an important biomarker for identification of kidney diseases. Early urea detection using a specific and sensitive technique can significantly reduce the mortality of patients. The research aims at developing fluorescence-based FITCmediated pH and urea measurement. A system containing FITC-dextran in alginate microspheres was developed using air-driven atomization. pH/Urea biosensor was characterized using optical microscopy, SEM, and CLSM. Urea biosensing studies were performed by exposing different standard solutions of pH and urea standard solutions using fluorescence spectroscopy (?ex=488 nm and ?em=520 nm). FITC-dextran was entrapped using an encapsulation unit and alginate microspheres were formed. The microspheres were found to be uniform and spherical in nature with sizes (50±10?). FITC-dextran was found to be uniformly distributed in the alginate microspheres as per the CLSM scans. Urea biosensing studies indicate that a linear correlation was observed with increasing urea concentrations. The said microspheres can be used to detect changes in pH from 4-8 units owing to its linear response in this range. FITC dextran loaded alginate microspheres showed an improved range of detection upto 7 mM in comparison to 1.5 mM when in solution phase in a study with urea concentrations from 0-50 mM. The pH and urea detection was accurate to an extent of interday variation of 5%. FITC-dextran loaded alginate microspheres show a great potential for usage as a pH and urea biosensor for early detection of kidney diseases.

Joshi, Abhijeet; Chaudhari, Rashmi; Srivastava, Rohit

2014-04-01

261

[Source analysis of urea-N in Lake Taihu during summer].  

PubMed

To study the effect of urea nitrogen on the ecosystem of Lake Taihu, we conducted urea and various nitrogen analysis for the water samples collected from the lake and surrounding rivers during summer. The ecological index analysis of 82 sites in rivers and lake yielded the following results: (1) The urea nitrogen contents in Taihu ranged from 0.011 to 0.161 mg x L(-1), which was high in the northwest and low in the southeast, related to the main pollution sources distribution of its drainage basin. (2) The dissolved nitrogen was dominated by inorganic nitrogen and the ratio between ammonia nitrogen and nitrate nitrogen was 5: 1. The average percentage of urea nitrogen in total nitrogen, dissolved nitrogen, dissolved organic nitrogen and bioavailable nitrogen was respectively 2.28%, 5.91%, 15.86%, and 6.22%, which showed a significant ecological function in Taihu. (3) Urea nitrogen concentration in river was more than twice that in lake, and the lake river concentration was slightly higher than the river into the lake. (3) In Taihu, there was a transformation relationship between urea nitrogen and the nitrogen in other forms. It showed that urea nitrogen had a significant positive correlation with permanganate index and the other forms of nitrogen, and a significant negative correlation with dissolved oxygen. In addition, urea nitrogen was weakly and positively correlated with chlorophyll a, while closely related to the spatial distribution of benthos and zooplankton species. All the results above showed that urea nitrogen was the bridge of organic and inorganic nitrogen transformation, and was the sign of nitrogen cycle of Lake Taihu, which was controlled by the circulating rate. High nitrogen content (especially the organic nitrogen) and low dissolved oxygen content were the key contributors to the increased urea nitrogen content. In Taihu, the urea nitrogen content was affected by both exogenous input and endogenous release. PMID:25244836

Han, Xiao-Xi; Zhu, Guang-Wei; Xu, Hai; Wilhelm, Steven W; Qin, Bo-Qiang; Li, Zhao-Fu

2014-07-01

262

Effect of Alcohol Fermented Feed on Lactating Performance, Blood Metabolites, Milk Fatty Acid Profile and Cholesterol Content in Holstein Lactating Cows  

PubMed Central

A feeding experiment with 40 lactating Holstein cows and 4 dietary treatments was conducted to investigate supplementation with different levels of alcohol fermented feed to the TMR on lactating performance, blood metabolites, milk fatty acid profile and cholesterol concentration of blood and milk. Forty Holstein lactating cows (106±24 d post-partum; mean±SD) were distributed into four groups and randomly assigned to one of four treatments with each containing 10 cows per treatment. The treatment supplemented with TMR (DM basis) as the control (CON), and CON mixed with alcohol-fermented feeds (AFF) at a level of 5%, 10% and 15% of the TMR as T1, T2 and T3, respectively. Dry matter intake and milk yield were not affected by supplementation of AFF. An increased 4% FCM in the milk occurred in cows fed T3 diet compared with CON, while T1 and T2 diets decreased 4% FCM in a dose dependent manner. Supplementation of AFF increased the concentration of albumin, total protein (TP), ammonia, and high density lipoprotein-cholesterol in serum compared with CON. In contrast, supplementation with AFF clearly decreased concentration of blood urea nitrogen (BUN) and total cholesterol (TC) compare with CON. AFF supplementation increased the proportion of C18:1n9 and C18:2n6 compared to CON. A decrease in the concentration of saturated fatty acid (SFA) for T1, T2 and T3 resulted in an increased unsaturated fatty acid (USFA) to SFA ratio compared to CON. Concentration of cholesterol in milk fat was reduced in proportion to the supplemental level of AFF. Feeding a diet supplemented with a moderate level AFF to lactating cows could be a way to alter the feed efficiency and fatty acid profile of milk by increasing potentially human consumer healthy fatty acid without detrimental effects on feed intake and milk production. A substantially decreased cholesterol proportion in milk induced by supplementation AFF suggests that alcohol fermented feed may improve milk cholesterol levels without any negative effects in lactating cows. PMID:25049515

Li, X. Z.; Park, B. K.; Yan, C. G.; Choi, J. G.; Ahn, J. S.; Shin, J. S.

2012-01-01

263

Economic value of urea-treated straw fed to lactating buffaloes during the dry season in Nepal.  

PubMed

An experiment was conducted to study the effects of feeding urea-treated rice straw to lactating buffaloes in the Koshi Hills. Six pairs of similar buffaloes on farms were selected. All were given a conventional diet based on rice straw for four weeks, then one of each pair was given 15 to 20 kg/day of urea-treated rice straw for a period of four weeks while the control group received untreated rice straw. In the final four week period all animals were given the conventional diet. Feeding straw treated with 4% urea increased the voluntary intake of straw by 25% and increased milk yield by 1.6 litres/day compared with buffaloes fed the conventional diet containing untreated straw. Milk production remained elevated after the four-week treatment period had finished. The results show that buffalo cows fed urea-treated straw achieved better weight gain, and milk yield increased significantly (P less than 0.01) compared with the control animals. During the treatment period the net benefit was 4.0 (i.e. US$1.16) Nepalese currency rupees (NCRs) per day and the incremental rate of return was 46 per cent. Moreover, in the four weeks following the treatment period the net benefit was 10.0 NCRs (i.e. US$0.40) per day. Ensiling rice straw with 4% urea can be recommended as a safe, economical and suitable method for improving the nutritional value of rice straw on small farms in Nepal thus increasing milk production and liveweight of lactating buffaloes. The practice of feeding urea-treated straw is economic for farmers during the dry season from January to April.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1763435

Chemjong, P B

1991-08-01

264

Urea is not a universal cryoprotectant among hibernating anurans: evidence from the freeze-tolerant boreal chorus frog (Pseudacris maculata).  

PubMed

Freeze-tolerant organisms accumulate a diversity of low molecular weight compounds to combat negative effects of ice formation. Previous studies of anuran freeze tolerance have implicated urea as a cryoprotectant in the wood frog (Lithobates sylvatica). However, a cryoprotective role for urea has been identified only for wood frogs, though urea accumulation is an evolutionarily conserved mechanism for coping with osmotic stress in amphibians. To identify whether multiple solutes are involved in freezing tolerance in the boreal chorus frog (Pseudacris maculata), we examined seasonal and freezing-induced variation in several potential cryoprotectants. We further tested for a cryoprotective role for urea by comparing survival and recovery from freezing in control and urea-loaded chorus frogs. Tissue levels of glucose, urea, and glycerol did not vary significantly among seasons for heart, liver, or leg muscle. Furthermore, no changes in urea or glycerol levels were detected with exposure to freezing temperatures in these tissues. Urea-loading increased tissue urea concentrations, but failed to enhance freezing survival or facilitate recovery from freezing in chorus frogs in this study, suggesting little role for urea as a natural cryoprotectant in this species. These data suggest that urea may not universally serve as a primary cryoprotectant among freeze-tolerant, terrestrially hibernating anurans. PMID:23142424

Higgins, Steven A; Swanson, David L

2013-02-01

265

Effect of protein intake and urea on sodium excretion during inappropriate antidiuresis in rats.  

PubMed

Administration of urea to patients with the syndrome of inappropriate antidiuresis (SIAD) is thought to ameliorate hyponatremia by both producing an osmotic diuresis and diminishing ongoing natriuresis. The present study evaluated these effects in a rat model of SIAD utilizing dilutional hyponatremia induced by continuous infusion of 1-deamino-[8-D-arginine] vasopressin. Following 48 hours of sustained hyponatremia, separate groups of rats were then refed with either: (1) 5% dextrose alone, (2) a 20% protein chow, (3) an isocaloric protein deficient (0%) chow, or (4) the isocaloric protein-deficient chow supplemented with oral urea. Our results demonstrate that rats refed a 20% protein diet significantly improved their plasma [Na+] as compared to rats refed protein deficient diets, and this improvement was accompanied by decreases in natriuresis despite an increased glomerular filtration rate and an unchanged negative free water clearance. Identical effects were observed in rats refed a protein deficient diet but supplemented with oral urea, suggesting that urea generation from catabolism of dietary protein is responsible for the effect of protein refeeding to decrease urinary sodium excretion. Both the protein and urea refed rats had significantly higher inner medullary urea contents and concentrations compared to rats refed protein-deficient diets and also to rats studied immediately before protein refeeding, supporting the hypothesis that urea and dietary protein decrease natriuresis in patients with SIAD in association with increased inner medullary urea concentrations. PMID:3336285

Verbalis, J G; Baldwin, E F; Neish, P N; Robinson, A G

1988-01-01

266

Urea Monitor Based on Chemiluminescence and Electrolysis as a Marker for Dialysis Efficiency  

NASA Astrophysics Data System (ADS)

We have developed a practical urea monitor based on a chemiluminescent (CL) reaction of urea and hypobromous acid produced by electrolysis of sodium bromide (NaBr) for measuring urea concentration in spent dialysate at set intervals. A reagent containing 4×10-2 M hypobromous acid is produced by electrolysis of an electrolyte containing 5.9 M NaBr and 0.2 M sodium hydroxide (NaOH). Chemiluminescence is emitted by injection of spent hemodialysis fluid (0.11 ml) into the reagent, and the CL-intensity is measured by a photomultiplier tube using the photon counting technique. The CL-intensity is proportional to the 0.9th power of the urea concentration between 7×10-4 and 2×10-2 M. The urea monitor can determine the urea concentration in spent dialysate samples collected from the waste line of a dialyzer, and the time for the intermittent measurements including the cleaning cycle of the reaction chamber is 3 min. The urea concentrations measured by the monitor are in close agreement with those measured by the conventional enzyme colorimetric method using urease for the spent dialysate collected during a hemodialysis treatment, and the correlation coefficient is 0.93.

Ozaki, Masahiro; Okabayashi, Tohru; Ishimaru, Teppei; Hayashi, Kunihito; Hori, Jun'ya; Yamamoto, Isao; Nakagawa, Masuo

267

Effects of abomasal infusion of flaxseed (Linum usitatissimum) oil on microbial ?-glucuronidase activity and concentration of the mammalian lignan enterolactone in ruminal fluid, plasma, urine and milk of dairy cows.  

PubMed

Ruminal microbiota plays an important role in the conversion of plant lignans into mammalian lignans. The main mammalian lignan present in the milk of dairy cows fed flax products is enterolactone (EL). The objectives of the present study were to investigate the effects of abomasal infusion of flax oil on the metabolism of flax lignans and concentrations of EL in biological fluids of dairy cows. A total of six rumen-cannulated dairy cows were assigned within a 2 × 3 factorial arrangement of six treatments utilising flax hulls (0 and 15·9 % of DM) and abomasal infusion of flax oil (0, 250 and 500 g/d). There were six periods of 21 d each. Samples were collected during the last 7 d of each period and subjected to chemical analysis. Flax hull supplementation increased concentrations of EL in ruminal fluid, plasma, urine and milk, while flax oil infusion had no effect. Post-feeding, ?-glucuronidase activity in the ruminal fluid of cows infused with 250 g flax oil was significantly lower for cows fed hulls than for those fed the control diet. The present study demonstrated that the presence of a rich source of n-3 fatty acids such as flax oil in the small intestine does not interfere with the absorption of the mammalian lignan EL and that lower ruminal ?-glucuronidase activity had no effect on the conversion of flax lignans into EL in the rumen of dairy cows. PMID:22717302

Côrtes, Cristiano; da Silva-Kazama, Daniele; Kazama, Ricardo; Benchaar, Chaouki; dos Santos, Geraldo; Zeoula, Lucia M; Gagnon, N; Petit, Hélène V

2013-02-14

268

Antibiotics in Milk—A Review1  

Microsoft Academic Search

SUIVi I~IARY The widespread use of antibiotics has contributed to the control of diseases and the nutritional well-being of livestock. However, the use of antibiotics in the treatment of mastitis has created problems for the milk processor and consumer. Following treatment of mastitis with antibiotics, they may be found in the milk in sufficient concentrations to inhibit dairy starter microorganisms

J. L. Albright; S. L. Tuckey; G. T. Woods

1961-01-01

269

Milk Biologically Active Components as Nutraceuticals: Review  

Microsoft Academic Search

Milk contains components that provide critical nutritive elements, immunological protection, and biologically active substances to both neonates and adults. Milk proteins are currently the main source of a range of biologically active peptides. Concentrates of these peptides are potential health-enhancing nutraceuticals for food and pharmaceutical applications. Several bioactive peptides may be used as nutraceuticals, for example, in the treatment of

Sindayikengera Séverin; Xia Wenshui

2005-01-01

270

Urea biosensor for hemodialysis monitoring  

DOEpatents

An electrochemical sensor capable of detecting and quantifying urea in fluids resulting from hemodialysis procedures. The sensor is based upon measurement of the pH change produced in an aqueous environment by the products of the enzyme-catalyzed hydrolysis of urea. The sensor may be fabricated using methods amenable to mass fabrication, resulting in low-cost sensors and thus providing the potential for disposable use. In a typical application, the sensor could be used in treatment centers, in conjunction with an appropriate electronics/computer system, in order to determine the hemodialysis endpoint. The sensor can also be utilized to allow at-home testing to determine if dialysis was necessary. Such a home monitor is similar, in principle, to devices used for blood glucose testing by diabetics, and would require a blood droplet sample by using a finger prick.

Glass, Robert S. (Livermore, CA)

1999-01-01

271

Urea biosensor for hemodialysis monitoring  

DOEpatents

This research discloses an electrochemical sensor capable of detecting and quantifying urea in fluids resulting from hemodialysis procedures. The sensor is based upon measurement of the pH change produced in an aqueous environment by the products of the enzyme-catalyzed hydrolysis of urea. The sensor may be fabricated using methods amenable to mass fabrication, resulting in low-cost sensors and thus providing the potential for disposable use. In a typical application, the sensor could be used in treatment centers, in conjunction with an appropriate electronics/computer system, in order to determine the hemodialysis endpoint. The sensor can also be utilized to allow at-home testing to determine if dialysis was necessary. Such a home monitor is similar, in principle, to devices used for blood glucose testing by diabetics, and would require a blood droplet sample by using a finger prick. 9 figs.

Glass, R.S.

1999-01-12

272

Effects of urea on the microstructure and phase behavior of aqueous solutions of polyoxyethylene surfactants  

PubMed Central

Membrane proteins are made soluble in aqueous buffers by the addition of various surfactants (detergents) to form so-called protein-detergent complexes (PDCs). Properties of membrane proteins are commonly assessed by unfolding the protein in the presence of surfactant in a buffer solution by adding urea. The stability of the protein under these conditions is then monitored by biophysical methods such as fluorescence or circular dichroism spectroscopy. Often overlooked in these experiments is the effect of urea on the phase behavior and micellar microstructure of the different surfactants used to form the PDCs. Here the effect of urea on five polyoxyethylene surfactants – n-octylytetraoxyethylene (C8E4), n-octylpentaoxyethylene (C8E5), n-decylhexaoxyethylene (C10E6), n-dodecylhexaoxyethylene (C12E6) and n-dodecyloctaoxylethylene (C12E8) – is explored. The presence of urea increases the critical micelle concentration (CMC) of all surfactants studied, indicating that the concentration of both the surfactant and urea should be considered in membrane protein folding studies. The cloud point temperature of all surfactants studied also increases with increasing urea concentration. Small-angle neutron scattering shows a urea-induced transition from an elongated to a globular shape for micelles of C8E4 and C12E6. In contrast, C8E5 and C12E8 form more globular micelles at room temperature and the micelles remain globular as the urea concentration is increased. The effects of increasing urea concentration on micelle structure are analogous to those of decreasing the temperature. The large changes in micelle structure observed here could also affect membrane protein unfolding studies by changing the structure of the PDC. PMID:21359094

Bianco, Carolina L.; Schneider, Craig S.; Santonicola, Mariagabriella; Lenhoff, Abraham M.; Kaler, Eric W.

2010-01-01

273

Role for urea in nitrification by polar marine Archaea  

PubMed Central

Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters. PMID:23027926

Alonso-Saez, Laura; Waller, Alison S.; Mende, Daniel R.; Bakker, Kevin; Farnelid, Hanna; Yager, Patricia L.; Lovejoy, Connie; Tremblay, Jean-Eric; Potvin, Marianne; Heinrich, Friederike; Estrada, Marta; Riemann, Lasse; Bork, Peer; Pedros-Alio, Carlos; Bertilsson, Stefan

2012-01-01

274

Role for urea in nitrification by polar marine Archaea.  

PubMed

Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters. PMID:23027926

Alonso-Sáez, Laura; Waller, Alison S; Mende, Daniel R; Bakker, Kevin; Farnelid, Hanna; Yager, Patricia L; Lovejoy, Connie; Tremblay, Jean-Éric; Potvin, Marianne; Heinrich, Friederike; Estrada, Marta; Riemann, Lasse; Bork, Peer; Pedrós-Alió, Carlos; Bertilsson, Stefan

2012-10-30

275

[Interaction of fluoride with milk constituents].  

PubMed

Fluoride concentrations have been studied in cow milk stemming from regions variably influenced by fluorine pollution. It was disclosed that fluoride concentration in the milk of cows grazing on areas with a high degree of environmental contamination by fluorine compounds was about three-fold higher as compared to the control group. Fluoride distribution was evaluated in milk, in which the protein sediment got separated from the whey. The said distribution was found to be equal in both of the milk constituents. Due to the decomposition of whey into the whey proteins sediment and the remaining solution, an answer was obtained to the question of which part of whey fluoride appeared in the ionized form (80%). Studying the binding of fluoride by isolating and purifying the fraction of milk proteins at various pH, it was revealed that alpha-lactalbumin bound fluoride at 3.9 pH. Because of limited caseins solubility at that pH, there was no possibility to find out whether they bound fluoride ions. At fresh milk pH, the caseins exist in the anionic form and as such they are unable to bind fluoride independently. The binding of fluoride with milk lipids was investigated and it was ascertained that about 11% of fluoride being introduced into milk were bound to lipid constituent. The study covered also the influence of fluoride ions on the magnitude of the optic polarization angle of aqueous lactose solutions in different concentrations. That angle undergoes diminution in comparison with solutions not polluted by fluoride. Fluoride concentration was defined in some milk formulas of Polish production designed for infants. They exceed, depending on the kind of formulas, 20-70 fold the average fluoride concentration evidenced in human milk. Thus, the differences in fluoride supplied to infants, fed by breast and artificially, are very great. PMID:8154621

Chlubek, D

1993-01-01

276

Supplemental methionine and urea for gestating beef cows consuming low quality forage diets.  

PubMed

A study was conducted to evaluate Met requirements of late-gestation beef cows consuming low quality forages on the premise that inadequate supply of metabolizable AA may limit protein accretion during pregnancy. Five ruminally cannulated, multiparous late-gestation beef cows (490 +/- 27 kg), of predominantly Angus (> or =75%) with Hereford and Simmental breeding, were used in a 5 x 5 Latin square experiment to evaluate the effects of postruminal dl-Met supplementation on N retention, serum metabolites, and plasma AA concentrations during the third trimester of pregnancy. The basal diet was fed individually, and weights of refusals were recorded for N intake determination. Treatments consisted of no urea, urea (0.053 +/- 0.002 g/kg of BW daily), urea + 5 g of Met/d, urea + 10 g of Met/d, and urea + 15 g of Met/d. Cows were adapted to the experimental diet 30 d before the beginning of the study, with periods lasting for 14 d; 4 d to allow for clearance of the previous treatment effects, 4 d for adaptation to the treatments, and 6 d for total fecal and urine collection. Blood samples were collected every 4 h on d 13 of each period for analysis of serum metabolites and plasma AA. Inclusion of urea increased DM and OM intakes (urea vs. no urea; P = 0.05), but no further improvement in intake was observed with inclusion of Met. Serum urea concentrations increased with inclusion of urea (P = 0.03) and responded quadratically (P = 0.06) when Met was added, with the lowest concentration observed in the urea + 5 g of Met/d treatment. More N was retained with the inclusion of urea (P = 0.04), and N retention increased linearly (P = 0.07) with inclusion of Met. Plasma Met concentration increased linearly (P < 0.01) with inclusion of Met. These data suggest that Met was a limiting AA and that supplementation of a combination of urea and 5 g/d of rumen-protected Met to low quality, forage diets will improve N retention and promote protein accretion during late pregnancy. PMID:17060412

Waterman, R C; Löest, C A; Bryant, W D; Petersen, M K

2007-03-01

277

Transfer of dietary zinc and fat to milk--evaluation of milk fat quality, milk fat precursors, and mastitis indicators.  

PubMed

The present study demonstrated that the zinc concentration in bovine milk and blood plasma is significantly affected by the intake of saturated fat supplements. Sixteen Holstein cows were used in a 4 x 4 Latin square design with 4 periods of 12 d, and 4 dietary treatments were conducted. A total mixed ration based on corn silage, grass-clover silages, and pelleted sugar beet pulp was used on all treatments. A high de novo milk fat diet was formulated by adding rapeseed meal and molasses in the total mixed ration [39 mg of Zn/kg of dry matter (DM)], and a low de novo diet by adding saturated fat, fat-rich rapeseed cake, and corn (34 mg of Zn/kg of DM). Dietary Zn levels were increased by addition of ZnO to 83 and 80 mg of Zn/kg of DM. Treatments did not affect daily DM intake, or yield of energy-corrected milk, milk fat, or milk protein. The high de novo diet significantly increased milk fat percentage and milk content of fatty acids with chain length from C6 to C16, and decreased content of C18 and C18:1. Treatments did not influence milk free fatty acids at 4 degrees C at 0 or 28 h after milking. The average diameter of milk fat globules was significantly greater in milk from cows offered low de novo diets. Furthermore, the low de novo diet significantly increased the concentration of nonesterified fatty acids and d-beta-hydroxybutyrate in blood plasma, the latter was also increased in milk. Treatments did not affect the enzyme activity of lactate dehydrogenase and N-acetyl-beta-d-glucosaminidase in milk or the activity of isocitrate dehydrogenase and malate dehydrogenase in blood plasma. The low de novo diet significantly increased plasma Zn and milk Zn content, whereas dietary Zn level did not in itself influence these parameters. This indicates that the transfer of fat from diet to milk might facilitate transfer of Zn from diet to milk. PMID:18349247

Wiking, L; Larsen, T; Sehested, J

2008-04-01

278

Vetiver grass is capable of removing TNT from soil in the presence of urea.  

PubMed

The high affinity of vetiver grass for 2,4,6 trinitrotoluene (TNT) and the catalytic effectiveness of urea in enhancing plant uptake of TNT in hydroponic media we earlier demonstrated were further illustrated in this soil-pot-experiment. Complete removal of TNT in urea-treated soil was accomplished by vetiver at the low initial soil-TNT concentration (40 mg kg(-1)), masking the effect of urea. Doubling the initial TNT concentration (80 mg kg(-1)) significantly (p<0.002) increased TNT removal by vetiver, in the presence of urea. Without vetiver grass, no significant (p=0.475) change in the soil-TNT concentrations was observed over a period of 48 days, suggesting that natural attenuation of soil TNT could not explain the documented TNT disappearance from soil. PMID:20047780

Das, Padmini; Datta, Rupali; Makris, Konstantinos C; Sarkar, Dibyendu

2010-05-01

279

SANS and DLS Studies of Protein Unfolding in Presence of Urea and Surfactant  

SciTech Connect

Small-angle neutron scattering (SANS) and dynamic light scattering (DLS) have been used to study conformational changes in protein bovine serum albumin (BSA) during its unfolding in presence of protein denaturating agents urea and surfactant. On addition of urea, the BSA protein unfolds for urea concentrations greater than 4 M and acquires a random coil configuration with its radius of gyration increasing with urea concentration. The addition of surfactant unfolds the protein by the formation of micelle-like aggregates of surfactants along the unfolded polypeptide chains of the protein. The fractal dimension of such a protein-surfactant complex decreases and the overall size of the complex increases on increasing the surfactant concentration. The conformation of the unfolded protein in the complex has been determined directly using contrast variation SANS measurements by contrast matching the surfactant to the medium. Results of DLS measurements are found to be in good agreement with those obtained using SANS.

Aswal, V. K.; Chodankar, S. N.; Wagh, A. G. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kohlbrecher, J.; Vavrin, R. [Laboratory for Neutron Scattering, ETH Zurich and Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

2008-03-17

280

Urea-induced modification of cytochrome c flexibility as probed by cyanide binding.  

PubMed

Cyanide binding to cytochrome c was monitored by absorption spectroscopy from neutral to acidic pH in the presence of urea. These results were compared with acid-induced unfolding at corresponding urea concentration monitored by absorption spectroscopy and circular dichroism. The association rate constant ka increased 20-fold when the concentration of urea was raised from 0M to 6M at neutral pH. However, the secondary structure of the protein was not affected, i.e. there was no striking conformational change in these urea concentrations at neutral pH. At the pH that was very close to the pK of acid-induced unfolding, the ka value reached its maximum (ka,max) in all urea concentrations. Interestingly, the ka,max value increased exponentially with increasing urea concentrations. These results are interpreted in terms of a change in the flexibility of the least stable part of the cyt c structure that is responsible for the Fe-S(Met80) bond disruption and for ligand binding to heme iron. PMID:23337638

Varha?, Rastislav

2013-04-01

281

An Investigation of Milk Sugar.  

ERIC Educational Resources Information Center

Describes an experiment to identify lactose and estimate the concentration of lactose in a sample of milk. Gives a background of the investigation. Details the experimental method, results and calculations. Discusses the implications of the experiment to students. Suggests further experiments using the same technique used in "miniprojects." (CW)

Smith, Christopher A.; Dawson, Maureen M.

1987-01-01

282

Occurrence of aflatoxin M1 in raw and market milk commercialized in Greece  

Microsoft Academic Search

From December 1999 to May 2000, 114 samples of pasteurized, ultrahigh temperature-treated (UHT) and concentrated milk were collected in supermarkets, whereas 52 raw milk samples from cow, sheep and goat were obtained from different milk producers all over Greece. Sample collection was repeated from December 2000 to May 2001 and concerned 54 samples of pasteurized milk, 23 samples of bulk-tank

V. Roussi; A. Govaris; A. Varagouli; N. A. Botsoglou

2002-01-01

283

Milk from Forage as Affected by Carbohydrate Source and Degradability with Alfalfa Silage-Based Diets  

Microsoft Academic Search

Milk from forage (MF) is an estimation of the milk produced solely from forage intake. It is calculated by subtracting milk production theoretically allowed by concentrates from total milk production, assuming that maintenance requirements are covered by the forage portion of the diet. Eight multiparous Holstein cows in early lactation were used in a replicated 4 × 4 Latin square

E. Charbonneau; P. Y. Chouinard; G. Allard; H. Lapierre; D. Pellerin

2006-01-01

284

21 CFR 131.111 - Acidified milk.  

Code of Federal Regulations, 2010 CFR

...acid, citric acid, fumaric acid, glucono-delta- lactone, hydrochloric acid, lactic acid, malic acid, phosphoric acid, succinic acid, and tartaric acid. (e) Other optional ingredients. (1) Concentrated skim milk, nonfat...

2010-04-01

285

Vitamin D metabolites in human milk  

SciTech Connect

The concentrations of unconjugated 25-OHD, 24, 25(OH)2D, and 1,25(OH)2D were measured in human milk by competitive protein-binding radioassays following successive preparative Sephadex LH-20 chromatography and HPLC. The mean (+/- SE) concentration of 25-OHD was 0.37 +/- 0.03 ng/ml, of 24,25(OH)2D was 24.8 +/- 1.9 pg/ml, and of 1,25(OH)2D was 2.2 +/-0.1 pg/ml. The concentration of 25-OHD3 in milk as determined by HPLC and UV detection at 254 nm was 0.27 +/- 0.08 ng/ml. The milk concentrations of vitamin D metabolites did not correlate with the maternal serum 25-OHD levels. The total amounts of unconjugated vitamin D metabolites correspond to the known low bioassayable vitamin D antirachitic activity in human milk.

Weisman, Y.; Bawnik, J.C.; Eisenberg, Z.; Spirer, Z.

1982-05-01

286

Urea Transformation of Wetland Microbial Communities  

Microsoft Academic Search

Transformation of urea to ammonium is an important link in the nitrogen cycle in soil and water. Although microbial nitrogen\\u000a transformations, such as nitrification and denitrification, are well studied in freshwater sediment and epiphytic biofilm\\u000a in shallow waters, information about urea transformation in these environments is scarce. In this study, urea transformation\\u000a of sedimentary, planktonic, and epiphytic microbial communities was

Ann-Karin Thorén

2007-01-01

287

A Simplified Method for Measuring the Entropy Change of Urea Dissolution. An Experiment for the Introductory Chemistry Lab  

NASA Astrophysics Data System (ADS)

The enthalpy change, equilibrium constant, Gibbs free energy change, and entropy change of the dissolution of urea in water were determined in a guided-inquiry lab experiment. Introductory-level students were able to obtain quite satisfactory thermodynamic values for the dissolution of urea using minimal equipment and a very simple procedure. The enthalpy change of dissolution was determined with a simple coffee-cup calorimeter. Students then directly determined the concentration of a saturated solution of urea simply by measuring the amount of urea used and the total volume of the solution as prepared in a graduated cylinder. The equilibrium expression for the dissolution of urea can be simplified to K = [urea]. With the enthalpy change and the equilibrium constant determined experimentally, the free energy change and enthalpy change for the process are readily calculated.

Liberko, Charles A.; Terry, Stephanie

2001-08-01

288

Managing Milk Composition: Evaluating Herd Potential  

E-print Network

Managing Milk Composition: Evaluating Herd Potential Sandra R. Stokes, Dan N. Waldner, Ellen R. Jordan, and Michael L. Looper* * Respectively, Extension Dairy Specialist, The Texas A&M University System; Extension Dairy Specialist, Oklahoma State... and can be altered over a range of nearly 3.0 percentage units. Milk protein concentration can also be altered by dietary manipulation. However, compared to the alterations possible in fat concentration, the range is much smaller at approximately 0...

Stokes, Sandra R.; Jordan, Ellen R.; Looper, Mike; Waldner, Dan

2000-12-11

289

Association between the bovine milk metabolome and rennet-induced coagulation properties of milk.  

PubMed

The milk metabolomes of 407 individual Swedish Red dairy cows were analyzed by nuclear magnetic resonance spectroscopy as part of the Danish-Swedish Milk Genomics Initiative. By relating these metabolite profiles to total milk protein concentration and rheological measurements of rennet-induced milk coagulation together using multivariate data analysis techniques, we were able to identify several different associations of the milk metabolome to technological properties of milk. Several novel correlations of milk metabolites to protein content and rennet-induced coagulation properties were demonstrated. Metabolites associated with the prediction of total protein content included choline, N-acetyl hexosamines, creatinine, glycerophosphocholine, glutamate, glucose 1-phosphate, galactose 1-phosphate, and orotate. In addition, levels of lactate, acetate, glutamate, creatinine, choline, carnitine, galactose 1-phosphate, and glycerophosphocholine were significantly different when comparing noncoagulating and well-coagulating milks. These findings suggest that the mentioned metabolites are associated with milk protein content and rennet-induced coagulation properties and may act as quality markers for cheese milk. PMID:25087032

Sundekilde, Ulrik K; Gustavsson, Frida; Poulsen, Nina A; Glantz, Maria; Paulsson, Marie; Larsen, Lotte B; Bertram, Hanne C

2014-10-01

290

Contribution of proteolytic activity associated with somatic cells in milk to cheese ripening  

Microsoft Academic Search

The effect of proteolytic enzymes from somatic cells on cheese quality was studied. In preliminary experiments, milk and two sodium caseinate systems (pH 6.5 and pH 5.2, the latter in the presence of 5% NaCl) were used as substrates to investigate the proteolytic activity of somatic cells recovered from mastitic milk. Urea-polyacrylamide gel electrophoretograms of hydrolysates suggested that somatic cell

R. Marino; T. Considine; A. Sevi; P. L. H. McSweeney; A. L. Kelly

2005-01-01

291

Combining a Laboratory Practical Class with a Computer Simulation: Studies on the Synthesis of Urea in Isolated Hepatocytes.  

ERIC Educational Resources Information Center

Describes how a computer simulation is used with a laboratory experiment on the synthesis of urea in isolated hepatocytes. The simulation calculates the amount of urea formed and the amount of ammonium remaining as the concentrations of ornithine, citrulline, argininosuccinate, arginine, and aspartate are altered. (JN)

Bender, David A.

1986-01-01

292

Human milk and breast feeding: an update on the state of the art.  

PubMed

Current approaches to infant feeding have been based on the level of available knowledge of nutritional requirements of full term and low birth weight (LBW) infants and on established cultural traditions in many contemporary societies. This discussion summarizes existing information about infant nutrition and immunobiologic aspects of human milk, which may influence the choice of breast versus bottle feeding of infants in different parts of the world. The average caloric requirement for a normal full term infant from the 2nd day of age through the 1st year of life is estimated to be about 100-110 Kcal/kg/day. Caloric intake of less than 80 Kcal/kg/day is usually insufficient for physiologic needs and intakes over the average requirement may be associated with obesity. The minimum requirement for protien has been estimated to be about 1.8 gm/100 Kcal and protein intake of over 4.5 gm/100 Kcal may result in an increased urea nitrogen retention. The nutritional requirements of premature and LBW infants have not been clearly established, but the nutritional needs of a LBW infant appear to be significantly higher than the requirements of a normal full term infant. The chemical composition of human milk exhibits considerable variation between different individuals and in the same individual at different times of lactation, as well as between samples obtained from mothers of LBW infants and full term infants. Fresh milk contains a wealth of components that provide specific and nonspecific defenses against infectious agents or other macromolecules. The concentrations of protein, whey protein nitrogen, sodium and potassium in cow's milk are 2-3 times higher than in human milk. Only limited information is available about the spectrum of environmental chemical and toxins present in cow's milk. The composition of human milk meets the minimum requirements for protein and calories for a growing full term infant, despite the fact that protein content of pooled human milk is low (0.9 gm/ml). Breastfeeding seems to result in a more balanced solute load because breastfed babies appear to require less water than babies fed on cow's milk. Commercial formula products often require reconstitution and supplementation with certain additives during manufacture or at the time of its feeding to the infant. Careful, but sparse epidemiologic studies conducted recently in several rural and urban settings, demonstrated a striking resistance of breastfed infants to colonization by coliform organisms. In modern times possibly the single most important consideration for the use of breastfeeding is its cost. Infants fed human milk do not grow as rapidly as those fed most commercial formulas, but there is no evidence to suggest that rapid growth is a desirable goal of nutrition for normal neonates. Conclusive evidence of overwhelming nutritional advantages of human nilk and breastfeeding over commercial milk products (which are properly reconstituted under sterile conditions) is not available at this time. PMID:7043382

Ogra, P L; Greene, H L

1982-04-01

293

Purification of RNA from milk whey.  

PubMed

MicroRNAs (miRNAs) are small regulatory RNA molecules that modulate specific target mRNAs and play very important roles in physiological processes. They were recently detected in body fluids such as blood, urine, saliva, and milk. These body fluid miRNAs have been studied thoroughly as potential diagnostic biomarkers. However, there have been few studies of milk miRNAs, and their roles are not clearly understood. Milk is the only nutritional source for newborn infants, and bovine milk is used widely as a dairy product. Thus, it is important to study milk miRNAs. In general, body fluid RNA concentrations are extremely low and of diverse existence types. In this chapter, we compare two silica membrane column-based RNA purification kits, and also compare RNA obtained directly from whey with that isolated from whey-derived exosomes. PMID:23719952

Izumi, Hirohisa; Kosaka, Nobuyoshi; Shimizu, Takashi; Sekine, Kazunori; Ochiya, Takahiro; Takase, Mitsunori

2013-01-01

294

40 CFR 721.9925 - Aminoethylethylene urea methacrylamide.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Aminoethylethylene urea methacrylamide. 721.9925 Section...Substances § 721.9925 Aminoethylethylene urea methacrylamide. (a) Chemical substance...identified generically as an aminoethylethylene urea methacrylamide (PMN...

2010-07-01

295

Structural characteristics that stabilize or destabilize different assembly levels of phycocyanin by urea.  

PubMed

Phycocyanin is one of the two phycobiliproteins always found in the Phycobilisome antenna complex. It is always situated at the ends of the peripheral rods, adjacent to the core cylinders composed of allophycocyanin. The basic phycocyanin monomer is an (??) dimer of globin-like subunits with three covalently linked phycocyanobilin cofactors. Monomers assemble further into trimers, hexamers, and rods which include non-pigmented linker proteins. Upon isolation in low ionic strength solution, rods quickly disintegrate into phycocyanin trimers, which lose contacts with other phycobiliproteins and with the linker proteins. The trimers, however, are quite stable and only the presence of high concentrations of chaotropic agents (such as urea), very acidic solutions, or elevated temperatures induces monomerization, followed by separation between the subunits. We have recently determined the crystal structures of phycocyanin from the thremophilic cyanobacterium Thermosynechococcus vulcanus in the presence of 2 or 4 M urea, and shown that 4 M urea monomerizes the phycocyanin trimers. In this paper, we will describe the phycocyanin structures in 2 and 4 M urea more completely. By mapping out the urea positions, we describe the structural elements within the trimeric interaction interface that may be interrupted by the presence of 4 M urea. In addition, we also identify what are the structural characteristics that prevent 4 M urea from inducing subunit dissociation. PMID:24687534

Marx, Ailie; Adir, Noam

2014-07-01

296

Catalytic hydrolysis of urea from wastewater using different aluminas by a fixed bed reactor.  

PubMed

In order to find an effective method for treating urea wastewater, the experiments on the hydrolysis of urea in wastewater were conducted in a fixed bed reactor with different aluminas (?-Al2O3, ?-Al2O3, and ?-Al2O3) as catalysts respectively in contrast with inert ceramic particle. The results indicate that the three alumina catalysts show obvious catalytic activity for urea hydrolysis at 125 °C. The order of activity is ?-Al2O3?>??-Al2O3?>??-Al2O3, and the activity difference increases with increasing temperature. According to the characterization results, surface acidity has little impact on the activity of catalyst. However, it was found that surface basicity of alumina catalyst plays an important role in catalytic hydrolysis of urea, and the activity of catalyst may be also influenced by the basic strength. With ?-Al2O3 as catalyst, the urea concentration in wastewater is reduced to 4.96 mg/L at a temperature of 165 °C. Moreover, the ?-Al2O3 shows a good stability for urea hydrolysis. The hydrolysis of urea over ?-Al2O3 catalyst can evidently reduce the reaction temperature and is promising to replace industrial thermal hydrolysis process. PMID:24952253

Shen, Shuguang; Li, Meina; Li, Binbin; Zhao, Zhijun

2014-11-01

297

The structural basis of urea-induced protein unfolding in ?-catenin.  

PubMed

Although urea and guanidine hydrochloride are commonly used to denature proteins, the molecular underpinnings of this process have remained unclear for a century. To address this question, crystal structures of ?-catenin were determined at various urea concentrations. These structures contained at least 105 unique positions that were occupied by urea molecules, each of which interacted with the protein primarily via hydrogen bonds. Hydrogen-bond competition experiments showed that the denaturing effects of urea were neutralized when polyethylene glycol was added to the solution. These data suggest that urea primarily causes proteins to unfold by competing and disrupting hydrogen bonds in proteins. Moreover, circular-dichroism spectra and nuclear magnetic resonance (NMR) analysis revealed that a similar mechanism caused protein denaturation in the absence of urea at pH levels greater than 12. Taken together, the results led to the conclusion that the disruption of hydrogen bonds is a general mechanism of unfolding induced by urea, high pH and potentially other denaturing agents such as guanidine hydrochloride. Traditionally, the disruption of hydrophobic interactions instead of hydrogen bonds has been thought to be the most important cause of protein denaturation. PMID:25372676

Wang, Chao; Chen, Zhongzhou; Hong, Xia; Ning, Fangkun; Liu, Haolin; Zang, Jianye; Yan, Xiaoxue; Kemp, Jennifer; Musselman, Catherine A; Kutateladze, Tatinna G; Zhao, Rui; Jiang, Chengyu; Zhang, Gongyi

2014-11-01

298

Simple chiral urea gelators, (R)- and (S)-2-heptylurea: their gelling ability enhanced by chirality.  

PubMed

We present the first report on the synthesis of chiral ureas, (R)- and (S)-2-heptylurea, and their gelling behaviors. The ureas were prepared by the reactions of chiral amines and phenyl carbamate in the presence of triethylamine. On cooling from homogeneous solutions, the chiral ureas form gels in water and various nonpolar organic solvents, such as cyclohexane, toluene, and tetrachloromethane, while the racemate gelatinize only toluene and tetrachloromethane among the solvents we examined. The gelling ability of the enantiomeric urea is higher than the racemate, as the critical gelling concentrations in toluene, for example, were 0.2% and 0.7% (wt/wt), respectively. The enhanced gelling ability of the enantiomeric ureas is due to the 1D supramolecular structure formed during gelation. In contrast, the racemate crystallizes into two-dimensional lamellae, where the (R)- and (S)-2-heptylurea exist alternatingly in a plane (P2(1)/c space group). Powder X-ray diffraction pattern of the enantiomeric urea showed that it has a different crystal lattice from that of the racemate, implying that the steric effect by the methyl group at the chiral center prevents the pure enantiomers from having 2D hydrogen bonding networks, which lead to sheet-like structures for the racemate and the achiral analog. Thus the pure enantiomers self-organize into one-dimensional fibrous structures. The simplicity and the ambidextrous gelling behaviors of the chiral ureas in forming both hydrogels and organogels present numerous possibilities for future applications. PMID:21396655

Kim, Jong-Uk; Schollmeyer, Dieter; Brehmer, Martin; Zentel, Rudolf

2011-05-15

299

Understanding Strategy of Nitrate and Urea Assimilation in a Chinese Strain of Aureococcus anophagefferens through RNA-Seq Analysis  

PubMed Central

Aureococcus anophagefferens is a harmful alga that dominates plankton communities during brown tides in North America, Africa, and Asia. Here, RNA-seq technology was used to profile the transcriptome of a Chinese strain of A. anophagefferens that was grown on urea, nitrate, and a mixture of urea and nitrate, and that was under N-replete, limited and recovery conditions to understand the molecular mechanisms that underlie nitrate and urea utilization. The number of differentially expressed genes between urea-grown and mixture N-grown cells were much less than those between urea-grown and nitrate-grown cells. Compared with nitrate-grown cells, mixture N-grown cells contained much lower levels of transcripts encoding proteins that are involved in nitrate transport and assimilation. Together with profiles of nutrient changes in media, these results suggest that A. anophagefferens primarily feeds on urea instead of nitrate when urea and nitrate co-exist. Furthermore, we noted that transcripts upregulated by nitrate and N-limitation included those encoding proteins involved in amino acid and nucleotide transport, degradation of amides and cyanates, and nitrate assimilation pathway. The data suggest that A. anophagefferens possesses an ability to utilize a variety of dissolved organic nitrogen. Moreover, transcripts for synthesis of proteins, glutamate-derived amino acids, spermines and sterols were upregulated by urea. Transcripts encoding key enzymes that are involved in the ornithine-urea and TCA cycles were differentially regulated by urea and nitrogen concentration, which suggests that the OUC may be linked to the TCA cycle and involved in reallocation of intracellular carbon and nitrogen. These genes regulated by urea may be crucial for the rapid proliferation of A. anophagefferens when urea is provided as the N source. PMID:25338000

Dong, Hong-Po; Huang, Kai-Xuan; Wang, Hua-Long; Lu, Song-Hui; Cen, Jing-Yi; Dong, Yue-Lei

2014-01-01

300

Understanding Strategy of Nitrate and Urea Assimilation in a Chinese Strain of Aureococcus anophagefferens through RNA-Seq Analysis.  

PubMed

Aureococcus anophagefferens is a harmful alga that dominates plankton communities during brown tides in North America, Africa, and Asia. Here, RNA-seq technology was used to profile the transcriptome of a Chinese strain of A. anophagefferens that was grown on urea, nitrate, and a mixture of urea and nitrate, and that was under N-replete, limited and recovery conditions to understand the molecular mechanisms that underlie nitrate and urea utilization. The number of differentially expressed genes between urea-grown and mixture N-grown cells were much less than those between urea-grown and nitrate-grown cells. Compared with nitrate-grown cells, mixture N-grown cells contained much lower levels of transcripts encoding proteins that are involved in nitrate transport and assimilation. Together with profiles of nutrient changes in media, these results suggest that A. anophagefferens primarily feeds on urea instead of nitrate when urea and nitrate co-exist. Furthermore, we noted that transcripts upregulated by nitrate and N-limitation included those encoding proteins involved in amino acid and nucleotide transport, degradation of amides and cyanates, and nitrate assimilation pathway. The data suggest that A. anophagefferens possesses an ability to utilize a variety of dissolved organic nitrogen. Moreover, transcripts for synthesis of proteins, glutamate-derived amino acids, spermines and sterols were upregulated by urea. Transcripts encoding key enzymes that are involved in the ornithine-urea and TCA cycles were differentially regulated by urea and nitrogen concentration, which suggests that the OUC may be linked to the TCA cycle and involved in reallocation of intracellular carbon and nitrogen. These genes regulated by urea may be crucial for the rapid proliferation of A. anophagefferens when urea is provided as the N source. PMID:25338000

Dong, Hong-Po; Huang, Kai-Xuan; Wang, Hua-Long; Lu, Song-Hui; Cen, Jing-Yi; Dong, Yue-Lei

2014-01-01

301

Determination of Vitamin A from Buffalo Milk Using HPLC Method  

Microsoft Academic Search

HPLC is a very sensitive method and also allows for the separation and determination of mixed vitamins, in very low concentrations. A number of 10 samples of Romanian buffalo milk were taken in wintertime, in order to detect the concentration of vitamin A using HPLC. Comparing the chromatograms of buffalo milk obtained is shown that there is a good correlation

Aurelia PECE; Adela PINTEA; Constantin BELE; Gheorghe MURESAN; Cristian COROIAN

302

Milk demystified by chemistry.  

PubMed

This article traces the decline of milk from a heavenly elixir to a tradeable food. Early cultures regarded milk not as a simple nutrient, but a living fluid. Heroes and gods were believed to have been nurtured by animals after being abandoned. Character traits were assumed to be transmitted by milk; infantile diseases were attributed to "bad milk", whereas "good milk" was used as a remedy. With chemical methods developed at the end of the 18th century, it became known that human milk was higher in sugar and lower in protein than cow's milk. During the 19th century, "scientific" feeding emerged that meant modifying cow's milk to imitate the proportion of nutrients in human milk. In Boston from 1893, Rotch initiated the "percentage" method, requiring a physician's prescription. In Paris from 1894, Budin sterilized bottled infant milk. In Berlin in 1898, Rubner measured oxygen and energy uptake by calorimetry, prompting feeding by calories, and Czerny introduced regulated feeding by the clock. These activities ignored the emotional dimension of infant nutrition and the anti-infective properties of human milk. They may have also enhanced the decline in breastfeeding, which reached an all-time low in 1971. Milk's demystification made artificial nutrition safer, but paved the way for commercially produced infant formula. PMID:24558227

Obladen, Michael

2014-09-01

303

Why Alter Milk Composition?  

Microsoft Academic Search

There are multiple reasons to alter milk composition. This paper delineates and discusses the processing, economic, regulatory, marketing, dietary, and future trends affecting alteration of milk compo- sition. The ability to divide milk into various components creates a multitude of products that can be used as ingredi- ents in both food and nonfood manufac- turing. In almost every use, there

David H. Hettinga

1989-01-01

304

Breast Milk Jaundice  

PubMed Central

The effect of breast milk and 3?, 20?-pregnanediol on the conjugation of bilirubin and o-aminophenol by rat liver was compared. Breast milk inhibited glucuronyl transferase, whereas 3?, 20?-pregnanediol inhibited the secretion of bilirubin glucuronide from rat liver slices. In the inhibitory breast milk examined the steroid was probably not the sole inhibitory factor. PMID:5576030

Hargreaves, T.; Piper, R. F.

1971-01-01

305

Nickel-cobalt bimetallic anode catalysts for direct urea fuel cell  

NASA Astrophysics Data System (ADS)

Nickel is an ideal non-noble metal anode catalyst for direct urea fuel cell (DUFC) due to its high activity. However, there exists a large overpotential toward urea electrooxidation. Herein, NiCo/C bimetallic nanoparticles were prepared with various Co contents (0, 10, 20, 30 and 40 wt%) to improve the activity. The best Co ratio was 10% in the aspect of cell performance, with a maximum power density of 1.57 mW cm-2 when 0.33 M urea was used as fuel, O2 as oxidant at 60°C. The effects of temperature and urea concentration on DUFC performance were investigated. Besides, direct urine fuel cell reaches a maximum power density of 0.19 mW cm-2 with an open circuit voltage of 0.38 V at 60°C.

Xu, Wei; Zhang, Huimin; Li, Gang; Wu, Zucheng

2014-08-01

306

Nickel-cobalt bimetallic anode catalysts for direct urea fuel cell  

PubMed Central

Nickel is an ideal non-noble metal anode catalyst for direct urea fuel cell (DUFC) due to its high activity. However, there exists a large overpotential toward urea electrooxidation. Herein, NiCo/C bimetallic nanoparticles were prepared with various Co contents (0, 10, 20, 30 and 40?wt%) to improve the activity. The best Co ratio was 10% in the aspect of cell performance, with a maximum power density of 1.57?mW cm?2 when 0.33?M urea was used as fuel, O2 as oxidant at 60°C. The effects of temperature and urea concentration on DUFC performance were investigated. Besides, direct urine fuel cell reaches a maximum power density of 0.19?mW cm?2 with an open circuit voltage of 0.38?V at 60°C. PMID:25168632

Xu, Wei; Zhang, Huimin; Li, Gang; Wu, Zucheng

2014-01-01

307

Enzymatic characterization of a prokaryotic urea carboxylase.  

PubMed

We identified the first prokaryotic urea carboxylase (UCA) from a member of the alpha subclass of the class Proteobacteria, Oleomonas sagaranensis. This enzyme (O. sagaranensis Uca) was composed of 1,171 amino acids, and its N-terminal region resembled the biotin carboxylase domains of various biotin-dependent carboxylases. The C-terminal region of the enzyme harbored the Met-Lys-Met motif found in biotin carboxyl carrier proteins. The primary structure of the enzyme was 45% identical to that of the urea carboxylase domain of urea amidolyase from Saccharomyces cerevisiae. O. sagaranensis Uca did not harbor the allophanate hydrolase domain found in the yeast enzyme, but a separate gene with structural similarity was found to be adjacent to the uca gene. Purified recombinant O. sagaranensis Uca displayed ATP-dependent carboxylase activity towards urea (V(max) = 21.2 micro mol mg(-1) min(-1)) but not towards acetyl coenzyme A (acetyl-CoA) and propionyl-CoA, indicating that the gene encoded a bona fide UCA and not an acetyl-CoA or propionyl-CoA carboxylase. The enzyme also exhibited high levels of activity towards acetamide and formamide. Kinetic parameters of the enzyme reaction were determined with ATP, urea, acetamide, and formamide. O. sagaranensis could grow on urea, acetamide, and formamide as sole nitrogen sources; moreover, ATP-dependent urea-degrading activity was found in cells grown with urea but not in cells grown with ammonia. The results suggest that the UCA of this organism may be involved in the assimilation of these compounds as nitrogen sources. Furthermore, orthologues of the O. sagaranensis uca gene were found to be widely distributed among Bacteria. This implies that there are two systems of urea degradation in Bacteria, a pathway catalyzed by the previously described ureases and the UCA-allophanate hydrolase pathway identified in this study. PMID:15090492

Kanamori, Takeshi; Kanou, Norihisa; Atomi, Haruyuki; Imanaka, Tadayuki

2004-05-01

308

Enzymatic Characterization of a Prokaryotic Urea Carboxylase  

PubMed Central

We identified the first prokaryotic urea carboxylase (UCA) from a member of the alpha subclass of the class Proteobacteria, Oleomonas sagaranensis. This enzyme (O. sagaranensis Uca) was composed of 1,171 amino acids, and its N-terminal region resembled the biotin carboxylase domains of various biotin-dependent carboxylases. The C-terminal region of the enzyme harbored the Met-Lys-Met motif found in biotin carboxyl carrier proteins. The primary structure of the enzyme was 45% identical to that of the urea carboxylase domain of urea amidolyase from Saccharomyces cerevisiae. O. sagaranensis Uca did not harbor the allophanate hydrolase domain found in the yeast enzyme, but a separate gene with structural similarity was found to be adjacent to the uca gene. Purified recombinant O. sagaranensis Uca displayed ATP-dependent carboxylase activity towards urea (Vmax = 21.2 ?mol mg?1 min?1) but not towards acetyl coenzyme A (acetyl-CoA) and propionyl-CoA, indicating that the gene encoded a bona fide UCA and not an acetyl-CoA or propionyl-CoA carboxylase. The enzyme also exhibited high levels of activity towards acetamide and formamide. Kinetic parameters of the enzyme reaction were determined with ATP, urea, acetamide, and formamide. O. sagaranensis could grow on urea, acetamide, and formamide as sole nitrogen sources; moreover, ATP-dependent urea-degrading activity was found in cells grown with urea but not in cells grown with ammonia. The results suggest that the UCA of this organism may be involved in the assimilation of these compounds as nitrogen sources. Furthermore, orthologues of the O. sagaranensis uca gene were found to be widely distributed among Bacteria. This implies that there are two systems of urea degradation in Bacteria, a pathway catalyzed by the previously described ureases and the UCA-allophanate hydrolase pathway identified in this study. PMID:15090492

Kanamori, Takeshi; Kanou, Norihisa; Atomi, Haruyuki; Imanaka, Tadayuki

2004-01-01

309

Induction of bovine polioencephalomalacia with a feeding system based on molasses and urea.  

PubMed Central

Polioencephalomalacia (PEM), a disease first described in the United States and related to intensive beef production, appeared in Cuba coincident with the use of a new, molasses-urea-based diet to fatten bulls. Because the only experimental means so far of reproducing PEM has been with amprolium, a structural analog of thiamin, the present study attempted to induce the disease using the molasses-urea-based diet. Six Holstein bulls (200-300 kg) were studied during consumption of three successive diets: 1) commercial molasses-urea-restricted forage diet of Cuban feedlots, 2) a period in which forage was gradually withdrawn and 3) a forage-free diet composed only of molasses, urea and fish meal. PEM was reproduced in this way. At ten-day intervals, blood concentrations of glucose, lactate, pyruvate and urea were measured, as well as when clinical signs of PEM appeared. The signs, clinical course and lesions of the experimentally induced disease were comparable to those of field cases. The biochemical results suggested a block in pyruvate oxidation as in PEM elsewhere in the world. No evidence existed of urea intoxication. In addition, brain and liver concentration of total thiamin from field cases and normal animals were found to be similar. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:1000370

Mella, C M; Perez-Oliva, O; Loew, F M

1976-01-01

310

Effect of urea on phase transition of poly(N-isopropylacrylamide) investigated by differential scanning calorimetry.  

PubMed

The effect of urea on the phase transition of PNIPAM was studied using differential scanning calorimetry (DSC). For a certain urea concentration, the enthalpy change of phase transition of poly(N-isopropylacrylamide) (PNIPAM) aqueous solution increases with the number of DSC cycles, presumably due to the displacement of water molecules bound to the amide groups of PNIPAM by urea molecules at the temperature higher than the lower critical solution temperature (LCST) of PNIPAM and causes the decrease in the absolute value of the exothermic heat related to the dehydration of hydrophilic groups and interactions of hydrophilic residues to around 0. Moreover, the enthalpy change decreases with the urea concentration during the heating process of the first DSC cycle, indicating the replacement of water molecules around the apolar isopropyl groups by urea molecules at the temperature lower than LCST, and the endothermic heat caused by the dehydration of apolar groups decreases. Furthermore, the urea molecules which replace the water molecules at high temperature can be replaced again by water molecules at the temperature lower than LCST, but this process needs several days to complete. PMID:25029067

Gao, Yating; Yang, Jinxian; Ding, Yanwei; Ye, Xiaodong

2014-08-01

311

Urea modulation of ?-amyloid fibril growth: Experimental studies and kinetic models  

PubMed Central

Aggregation of ?-amyloid (A?) into fibrillar deposits is widely believed to initiate a cascade of adverse biological responses associated with Alzheimer’s disease. Although it was once assumed that the mature fibril was the toxic form of A?, recent evidence supports the hypothesis that A? oligomers, intermediates in the fibrillogenic pathway, are the dominant toxic species. In this work we used urea to reduce the driving force for A? aggregation, in an effort to isolate stable intermediate species. The effect of urea on secondary structure, size distribution, aggregation kinetics, and aggregate morphology was examined. With increasing urea concentration, ?-sheet content and the fraction of aggregated peptide decreased, the average size of aggregates was reduced, and the morphology of aggregates changed from linear to a globular/linear mixture and then to globular. The data were analyzed using a previously published model of A? aggregation kinetics. The model and data were consistent with the hypothesis that the globular aggregates were intermediates in the amyloidogenesis pathway rather than alternatively aggregated species. Increasing the urea concentration from 0.4 M to 2 M decreased the rate of filament initiation the most; between 2 M and 4 M urea the largest change was in partitioning between the nonamyloid and amyloid pathways, and between 4 M and 6 M urea, the most significant change was a reduction in the rate of filament elongation. PMID:15459334

Kim, Jin Ryoun; Muresan, Adrian; Lee, Ka Yee C.; Murphy, Regina M.

2004-01-01

312

Indirect exposure screening model for evaluating contaminant intake from air emissions via ingestion of milk and beef: Risk-based air concentrations  

SciTech Connect

A conceptual model has been developed to estimate screening level, risk-based contaminant air concentrations with respect to human health risks from indirect exposures to air emission. The model can evaluate risks from products of incomplete combustion, principal organic hazardous constituents associated with hazardous waste incinerator emissions and other air emittants. Derivation of screening levels is facilitated with a computer spreadsheet requiring six input values. To avoid complex air modeling, estimates are used for some parameters, such as particle deposition rate. The risk-based air concentrations can be used in the early stages of a risk investigation (prior to the trial burn at some incinerator sites) for screening purposes. These risk-based air concentrations can be compared to air concentrations extrapolated from trial burn or other relevant site historical data to determine whether or not a significant risk due to indirect exposures may be present. If screening comparisons reveal the possibility of significant risks, a more extensive risk assessment analysis can be performed and risk-drivers can be identified early in the process. Conversely, if significant risk is clearly not present for contaminants of concern, the analysis can be concluded cost-effectively with the screening process.

Chew, C.M. [Roy F. Weston, Inc., Seattle, WA (United States); Lorenzana, R.M. [Environmental Protection Agency, Seattle, WA (United States); Garry, M. [Foster Wheeler Environmental Corp., Bellevue, WA (United States)

1997-09-01

313

Properties of the Colostrum of the Dairy Cow. V. Yield, Specific Gravity and Concentrations of Total Solids and its Various Components of Colostrum and Early Milk1  

Microsoft Academic Search

Considerable information on specific gravity and on concentrations of total solids, fat, protein, lactose and ash of colostrum has been accumulated. From the early studies, many of which are referred to by Houdini~re (7), Overman and Sanmann (8) and Weber (18), there emerged a general picture of the gross composition of colostrum and a recognition of its variability. Within the

D. B. Parrish; G. H. Wise; J. S. Hughes; F. W. Atkeson

1950-01-01

314

The Chinese soft-shelled turtle, Pelodiscus sinensis, excretes urea mainly through the mouth instead of the kidney.  

PubMed

The Chinese soft-shelled turtle, Pelodiscus sinensis, is well adapted to aquatic environments, including brackish swamps and marshes. It is ureotelic, and occasionally submerges its head into puddles of water during emersion, presumably for buccopharyngeal respiration. This study was undertaken to test the hypothesis that the buccophyaryngeal cavity constitutes an important excretory route for urea in P. sinensis. Results indicate that a major portion of urea was excreted through the mouth instead of the kidney during immersion. When restrained on land, P. sinensis occasionally submerged their head into water (20-100 min), during which urea excretion and oxygen extraction occurred simultaneously. These results indicate for the first time that buccopharyngeal villiform processes (BVP) and rhythmic pharyngeal movements were involved in urea excretion in P. sinensis. Urea excretion through the mouth was sensitive to phloretin inhibition, indicating the involvement of urea transporters (UTs). In addition, saliva samples collected from the buccopharyngeal surfaces of P. sinensis injected intraperitoneally with saline contained ~36 mmol N l(-1) urea, significantly higher than that (~2.4 mmol N l(-1)) in the plasma. After intraperitoneal injection with 20 ?mol urea g(-1) turtle, the concentration of urea in the saliva collected from the BVP increased to an extraordinarily high level of ~614 ?mol N ml(-1), but the urea concentration (~45 ?mol N ml(-1)) in the plasma was much lower, indicating that the buccopharyngeal epithelium of P. sinensis was capable of active urea transport. Subsequently, we obtained from the buccopharyngeal epithelium of P. sinensis the full cDNA sequence of a putative UT, whose deduced amino acid sequence had ~70% similarity with human and mouse UT-A2. This UT was not expressed in the kidney, corroborating the proposition that the kidney had only a minor role in urea excretion in P. sinensis. As UT-A2 is known to be a facilitative urea transporter, it is logical to deduce that it was localized in the basolateral membrane of the buccopharyngeal epithelium, and that another type of primary or secondary active urea transporter yet to be identified was present in the apical membrane. The ability to excrete urea through the mouth instead of the kidney might have facilitated the ability of P. sinensis and other soft-shelled turtles to successfully invade the brackish and/or marine environment. PMID:23053366

Ip, Yuen K; Loong, Ai M; Lee, Serene M L; Ong, Jasmine L Y; Wong, Wai P; Chew, Shit F

2012-11-01

315

A large response range reflectometric urea biosensor made from silica-gel nanoparticles.  

PubMed

A new silica-gel nanospheres (SiO2NPs) composition was formulated, followed by biochemical surface functionalization to examine its potential in urea biosensor development. The SiO2NPs were basically synthesized based on sol-gel chemistry using a modified Stober method. The SiO2NPs surfaces were modified with amine (-NH2) functional groups for urease immobilization in the presence of glutaric acid (GA) cross-linker. The chromoionophore pH-sensitive dye ETH 5294 was physically adsorbed on the functionalized SiO2NPs as pH transducer. The immobilized urease determined urea concentration reflectometrically based on the colour change of the immobilized chromoionophore as a result of the enzymatic hydrolysis of urea. The pH changes on the biosensor due to the catalytic enzyme reaction of immobilized urease were found to correlate with the urea concentrations over a linear response range of 50-500 mM (R2 = 0.96) with a detection limit of 10 mM urea. The biosensor response time was 9 min with reproducibility of less than 10% relative standard deviation (RSD). This optical urea biosensor did not show interferences by Na+, K+, Mg2+ and NH4+ ions. The biosensor performance has been validated using urine samples in comparison with a non-enzymatic method based on the use of p-dimethylaminobenzaldehyde (DMAB) reagent and demonstrated a good correlation between the two different methods (R2 = 0.996 and regression slope of 1.0307). The SiO2NPs-based reflectometric urea biosensor showed improved dynamic linear response range when compared to other nanoparticle-based optical urea biosensors. PMID:25054632

Alqasaimeh, Muawia; Heng, Lee Yook; Ahmad, Musa; Raj, A S Santhana; Ling, Tan Ling

2014-01-01

316

Urea cycle enzymes through the development of pacu (Piaractus mesopotamicus): the role of ornithine carbamoyl transferase.  

PubMed

The present work reports the activities of urea cycle enzymes during the ontogenic development of the teleost pacu (Piaractus mesopotamicus). Urea cycle enzymes from the kidney and liver of adult fish were compared with those from the fish's embryonic phases. Samples were evaluated over all phases of embryonic development, the larval period and alevin. Ammonia and urea concentrations were determined during embryogenesis and in the plasma of adult fish. Except for carbamoyl phosphate synthetase-III (CPS-III), all enzymes of the urea cycle were expressed in the larvae and alevins as well as in the liver and kidney of adult fish. In spite of the low level of activity of the ornithine urea cycle (OUC) enzymes compared to those in mammals, and the low levels of tissue urea concentration compared to ammonia, the ureogenesis was evaluated in pacu. Ammonia seems to be the main nitrogenous waste during embryonic development. In this phase glutamine synthetase (GS) may play a role in ammonia detoxification, and the OUC enzymes can be individually involved in functions other than urea production. The presence of ornithine carbamoyl transferase (OCT) in all developmental phases of pacu and in the adult liver and kidney suggests that this enzyme is performing different metabolic pathways. OCT in the kidney, wherein the activity is less than in the liver, should work in the biosynthesis of polyamines and control the arginine plasma concentration given that renal arginase and argininosuccinate synthetase-argininosuccinate lyase are more active than from the liver. We suppose that OCT during the embryogenesis is a control step regulating the cellular concentration of ornithine for polyamines synthesis. PMID:18649031

Monzani, Paulo Sérgio; Moraes, Gilberto

2008-06-01

317

Human milk banking.  

PubMed

Forms of human milk banking and donation have been present for more than a century worldwide, but, since 1985, the Human Milk Banking Association of North America (HM BANA) has established guidelines to make the use of donor's breast milk safe and the second best form of feeding to maternal breast milk for a neonatal intensive care unit (NICU) infant. The Indiana Mother's Human Milk Bank provides an extensive and meticulous process of selecting breast milk donors. The process begins with a phone interview with a potential donor and includes the review of the donor's medical records, blood laboratory screening, medication and dietary intake, as well as consent from the donor's pediatrician. The milk bank follows steps of collecting, storing, and receiving the breast milk in accordance with the guidelines of the HM BANA. Pasteurization is the method used to ensure the proper heating and cooling of breast milk. Despite the rigorous pasteurization method, the donor's breast milk will not lose most of the important beneficial components needed for sick or ill NICU infants. Every batch of pasteurized breast milk will be cultured for any possible contamination and shipped to NICUs after it has been cleared by laboratory testing. PMID:23666187

O'Hare, Esther Marie; Wood, Angela; Fiske, Elizabeth

2013-01-01

318

Effect of Feeding Limited Roughage and a Comparison between Loose and Pelleted Pineapple Hay on Milk Production, Milk Constituents, and Fatty Acid Composition of Milk Fat[1] and [2  

Microsoft Academic Search

Twelve lactating Holstein cows were used to evaluate limited roughage feeding and to compare the feeding value of loose and pelleted pineapple hay in terms of milk production, milk constituents, and fatty acid composition of milk fat. An incom- plete block switchback design consisting of 6-wk periods (3-wk changeover and 3-wk comparison periods) was used. Treatments were 1) high concentrate-

N. S. Dronawat; R. W. Stanley; E. Cobb; K. Morita

1966-01-01

319

Anuran amphibia which are not acclimable to high salt, tolerate high plasma urea.  

PubMed

1. The capacity of five anuran Amphibians (Bufo viridis, B. regularis, Rana ridibunda, Hyla arborea and Pelobates syriacus) to acclimate to NaCl and urea solutions was investigated. 2. All species could be acclimated to relatively high concentrations of urea solutions, while only Bufo viridis and Hyla arborea could be acclimated to 500 mOsm/kg or higher NaCl solutions. 3. The plasma urea concentration in B. viridis and H. arborea was elevated to levels over 140 mmol/l. 4. The sum of plasma sodium and chloride concentrations did not increase over 400 mmol/l in any species. 5. Urine osmolality, which was normally low, increased, but never exceeded the plasma osmolality. 6. In the urea acclimation conditions, urine electrolytes diminished, similarly in all species in this study. 7. It is concluded that anuran Amphibians can tolerate high plasma urea concentrations, but only those species which can elevate it, either through retention or net synthesis, can be acclimated to high salt solutions. PMID:1358505

Shpun, S; Hoffman, J; Katz, U

1992-11-01

320

Effect of milk composition upon the partition coefficents of diacetyl, acetaldehyde, and ethanol in acidified milk products  

E-print Network

SNF and milk fat concentrations in the milk matrix at either concentration of compounds or incubation temperature. The highest partition coefficients were observed in a milk matrix which contained 12% SNF or 20% milk fat. Interaction effects of SNF... by fat, SNF by pH, fat by pH, and SNF by fat by pH on the partition coefficient were not observed except for a fat by pH interaction for diacetyl. The partition coefficient for acetaldehyde was higher than the partition coefficient for diacetyl...

Lee, Kai-Ping

2012-06-07

321

Milk trace elements in lactating cows environmentally exposed to higher level of lead and cadmium around different industrial units  

Microsoft Academic Search

The present investigation was carried out to assess the trace mineral profile of milk from lactating cows reared around different industrial units and to examine the effect of blood and milk concentration of lead and cadmium on copper, cobalt, zinc and iron levels in milk. Respective blood and milk samples were collected from a total of 201 apparently healthy lactating

R. C. Patra; D. Swarup; P. Kumar; D. Nandi; R. Naresh; S. L. Ali

2008-01-01

322

[Chemical pollution and breast milk: Taking positions].  

PubMed

Chemical pollution affects all ecosystems of our planet. Human milk has been used as a biomarker of environmental pollution as, due to bioaccumulation processes in fat tissue, many chemical compounds reach measurable concentrations that can be readily tested in breast milk. Quite frequently information about the presence of contaminants in breast milk appears in the media, leading to misunderstanding among parents and health professionals, and in some cases breastfeeding the child is stopped. In this article, the Breastfeeding Committee of the Spanish Association of Paediatrics stresses the importance of promoting breastfeeding as the healthiest option, because its benefits clearly outweigh any health risks associated with chemical contaminants in breast milk. Breast milk contains protective factors that counteract the potential effects related to prenatal exposure to environmental pollutants. This article summarises the key recommendations to reduce the level of chemical contaminants in breast milk. It also highlights the importance of government involvement in the development of programs to eliminate or reduce chemical contamination of food and the environment. In this way, the negative effects on child health resulting from exposure to these toxic compounds through the placenta and breast milk may be prevented. PMID:23791806

Díaz-Gómez, N M; Ares, S; Hernández-Aguilar, M T; Ortega-García, J A; Paricio-Talayero, J M; Landa-Rivera, L

2013-12-01

323

Enzymatic urea adaptation: lactate and malate dehydrogenase in elasmobranchs.  

PubMed

Lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) electrophoretic tissue patterns of two different orders of Elasmobranchii: Carchariniformes (Galeus melanostomus and Prionace glauca) and Squaliformes (Etmopterus spinax and Scymnorinus licha) were studied. The number of loci expressed for these enzymes was the same of other elasmobranch species. Differences in tissue distribution were noted in LDH from G. melanostomus due to the presence of an additional heterotetramer in the eye tissue. There were also differences in MDH. In fact, all the tissues of E. spinax and G. melanostomus showed two mitochondrial bands. Major differences were noted in the number of isozymes detected in the four compared elasmobranchs. The highest polymorphism was observed in E. spinax and G. melanostomus, two species that live in changeable environmental conditions. The resistance of isozymes after urea treatment was examined; the resulting patterns showed a quite good resistance of the enzymes, higher for LDH than MDH, also at urea concentration much greater than physiological one. These results indicated that the total isozyme resistance can be considered higher in urea accumulators (such as elasmobranchs) than in the non-accumulators (such as teleosts). PMID:16497106

Laganà, G; Bellocco, E; Mannucci, C; Leuzzi, U; Tellone, E; Kotyk, A; Galtieri, A

2006-01-01

324

Developing Hypothetical Inhibition Mechanism of Novel Urea Transporter B Inhibitor  

NASA Astrophysics Data System (ADS)

Urea transporter B (UT-B) is a membrane channel protein that specifically transports urea. UT-B null mouse exhibited urea selective urine concentrating ability deficiency, which suggests the potential clinical applications of the UT-B inhibitors as novel diuretics. Primary high-throughput virtual screening (HTVS) of 50000 small-molecular drug-like compounds identified 2319 hit compounds. These 2319 compounds were screened by high-throughput screening using an erythrocyte osmotic lysis assay. Based on the pharmacological data, putative UT-B binding sites were identified by structure-based drug design and validated by ligand-based and QSAR model. Additionally, UT-B structural and functional characteristics under inhibitors treated and untreated conditions were simulated by molecular dynamics (MD). As the result, we identified four classes of compounds with UT-B inhibitory activity and predicted a human UT-B model, based on which computative binding sites were identified and validated. A novel potential mechanism of UT-B inhibitory activity was discovered by comparing UT-B from different species. Results suggest residue PHE198 in rat and mouse UT-B might block the inhibitor migration pathway. Inhibitory mechanisms of UT-B inhibitors and the functions of key residues in UT-B were proposed. The binding site analysis provides a structural basis for lead identification and optimization of UT-B inhibitors.

Li, Min; Tou, Weng Ieong; Zhou, Hong; Li, Fei; Ren, Huiwen; Chen, Calvin Yu-Chian; Yang, Baoxue

2014-07-01

325

Developing hypothetical inhibition mechanism of novel urea transporter B inhibitor.  

PubMed

Urea transporter B (UT-B) is a membrane channel protein that specifically transports urea. UT-B null mouse exhibited urea selective urine concentrating ability deficiency, which suggests the potential clinical applications of the UT-B inhibitors as novel diuretics. Primary high-throughput virtual screening (HTVS) of 50000 small-molecular drug-like compounds identified 2319 hit compounds. These 2319 compounds were screened by high-throughput screening using an erythrocyte osmotic lysis assay. Based on the pharmacological data, putative UT-B binding sites were identified by structure-based drug design and validated by ligand-based and QSAR model. Additionally, UT-B structural and functional characteristics under inhibitors treated and untreated conditions were simulated by molecular dynamics (MD). As the result, we identified four classes of compounds with UT-B inhibitory activity and predicted a human UT-B model, based on which computative binding sites were identified and validated. A novel potential mechanism of UT-B inhibitory activity was discovered by comparing UT-B from different species. Results suggest residue PHE198 in rat and mouse UT-B might block the inhibitor migration pathway. Inhibitory mechanisms of UT-B inhibitors and the functions of key residues in UT-B were proposed. The binding site analysis provides a structural basis for lead identification and optimization of UT-B inhibitors. PMID:25047372

Li, Min; Tou, Weng Ieong; Zhou, Hong; Li, Fei; Ren, Huiwen; Chen, Calvin Yu-Chian; Yang, Baoxue

2014-01-01

326

STATUS OF IODINE IN FORMALDEHYDE-PRESERVED MILK - REVISITED  

EPA Science Inventory

The effect of formaldehyde as a preservative for milk prior to radiochemical analysis for 131I was studied. Results suggest that the formaldehyde concentration is critical and that at low formaldehyde concentrations (...

327

Xenobiotic-urea conjugates; chemical or biological?  

PubMed

Abstract 1.?Although the major pathways involved in drug metabolism have been elucidated, there remain those routes that may be considered as minor, esoteric, or even artifactual. 2.?Conjugation with urea, an abundant, non-toxic, small water soluble molecule, is such a disputed and debatable Phase II pathway. 3.?The present article collates data gleaned from the literature concerning xenobiotic-urea conjugation, presents pertinent information resurrecting the controversy and poses questions as to the nature of the phenomenon. PMID:25144804

Mitchell, Stephen C

2014-12-01

328

Adiponectin is present in human milk and is associated with maternal factors1-3  

Microsoft Academic Search

Background:Previousstudieshaveshownthathumanmilkhasarole inthegastrointestinal,neural,andimmunedevelopmentofneonates.If present in milk, adiponectin would be a promising candidate for influ- encing infant development, given its metabolic functions. Objectives: Our objectives were to determine whether adiponectin is present in human milk and to characterize maternal factors asso- ciated with potential variation in milk adiponectin concentrations. Design: We quantified adiponectin concentrations in human milk samples from donors to the

Lisa J Martin; Jessica G Woo; Sheela R Geraghty; Mekibib Altaye; Barbara S Davidson; Walter Banach; Lawrence M Dolan; Guillermo M Ruiz-Palacios; Ardythe L Morrow

329

Original Article Effect of milk sampling techniques on milk  

E-print Network

Original Article Effect of milk sampling techniques on milk composition, bacterial contamination, viability and functions of resident cells in milk Frédéric VANGROENWEGHE, Hilde DOSOGNE, Jalil MEHRZAD June 2001) Abstract ­ Three different milk sampling techniques were evaluated during milk sampling

Paris-Sud XI, Université de

330

Unfolding mechanism of lysozyme in various urea solutions: Insights from fluorescence spectroscopy  

NASA Astrophysics Data System (ADS)

Fluorescence spectroscopic technique is very popular in exploring the folding/unfolding process of proteins. In this paper, unfolding process of hen egg-white lysozyme was investigated in various denaturing solutions. Firstly, polymer solution theory was employed to comprehend the dependence of fluorescence quenching effect on protein concentration, and dynamic contact concentration was suggested as a critical value for related fluorescence experiment. Secondly, it was found that urea alone could not completely unfold lysozyme but did when together with DTT or HCl. Lysozyme was destabilized in concentrated urea solution, but still could maintain its spatial structure. Phase diagram of fluorescence intensities revealed that HCl could enhance the denaturing capacity of urea, resulting in the emergence of intermediate state in the thermodynamic unfolding process of lysozyme.

Chen, Bang; Zhang, Hongjia; Xi, Wenying; Zhao, Liqing; Liang, Li; Chen, Yantao

2014-11-01

331

Effects of urea analogs on egg hatching and movement of unhatched larvae of monogenean parasite Acanthocotyle lobianchi from skin of Raja montagui  

Microsoft Academic Search

Rapid hatching in the monogenean parasiteAcanthocotyle lobianchi from the skin ofRaja montagui is stimulated by urea. Structurally similar to the urea molecule, the following analogs of urea provide amino groups, carboxyl groups, or combinations of these, but fail to stimulate hatching at concentrations of 1 mM in seawater: methylurea (MU); 1, 3-dimethylurea (DU); 1, 1, 3, 3-tetramethylurea (TMU); thiourea (TU);

Ian D. Whittington; Graham C. Kearn

1990-01-01

332

Influence of Carbohydrate Source and Buffer on Rumen Fermentation Characteristics, Milk Yield, and Milk Composition in Early-Lactation Holstein Cows  

Microsoft Academic Search

The effects of concentrate to forage ratio and sodium bicarbonate (buffer) supplementation on intake, rumi- nal fermentation characteristics, digestibility coeffi- cients, milk yield, and milk composition were examined in 4 cannulated Holstein cows (100 ± 20 d in milk). A 4 × 4 Latin square design with 2 × 2 factorial arrange- ment of treatments was implemented for 3-wk experi-

J. J. Kennelly; B. Robinson; G. R. Khorasani

1999-01-01

333

Effect of urea and urea–gamma treatments on cellulose degradation of Thai rice straw and corn stalk  

Microsoft Academic Search

Cellulose degradation of 20% urea treated and 20% urea–10kGy gamma treated Thai rice straw and corn stalk showed that combination effect of urea and gamma radiation gave a higher % decrease in neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose, hemicellulose, and lignin and cutin in comparison with urea effect only for both room temperature

Siriwattana Banchorndhevakul

2002-01-01

334

Effects of urea on the molecules involved in the olfactory signal transduction: a preliminary study on Danio rerio.  

PubMed

Among vertebrates, the physiologically uremic Chondrichthyes are the only class which are not presenting the ciliated olfactory receptor neurons in the olfactory neuroepithelium. The only sequenced genome for this class revealed only three olfactory receptor genes and the immunohistochemical detection of G protein alpha subunit typically coupled to the olfactory receptors (G?olf) failed in different species. Chronic renal disease can represent a cause of olfactory impairment in human. In this context, our present study focused on investigating potential effects of high urea concentration on the olfactory epithelium of vertebrates. Larvae of the teleost fish Danio rerio were exposed to urea in order to assess the effects on the olfactory signal transduction; in particular on both the olfactory receptors and the G?olf. The endocytosis of neutral red dye in the olfactory mucosa was detected in control and urea-exposed larvae. The amount of neutral red dye uptake was used as a marker of binding and internalization of the G?olf. The neutral red dye endocytosis was not affected by urea exposure, hence suggesting that the presence of the G?olf and their binding to the odorants are not affected by urea treatment, either. The presence and distribution of G?olf were investigated in the olfactory epithelium of control and urea-exposed larvae, using a commercial antibody. The immunoreactivity was increased after urea treatment, suggesting an effect of urea on the expression or degradation of this G protein alpha subunit. PMID:25092237

Ferrando, Sara; Gallus, Lorenzo; Gambardella, Chiara; Marchesotti, Emiliano; Ravera, Silvia; Franceschini, Valeria; Masini, Maria Angela

2014-12-01

335

[Hydrolyzed lactose contained in the ultrafiltrate of milk or milk products in an enzymatic membrane reactor].  

PubMed

Milk and milk by-products with a low lactose content, very interesting from a nutritional and technological point of view, were obtained by the application of the enzymatic membrane reactor technique. A previous separation of the aqueous phase of milk or ultrafiltrate was necessary and realized by ultrafiltration. The enzyme, a commercial beta-galactosidase, was maintained in solution in the retentate part of the membrane reactor. The optimal conditions of the lactose hydrolysis in milk and whey ultrafiltrates were determined. The behaviour of the aqueous phase of milk in membrane reactor, specially of mineral salts, was studied. Three possibilities were proposed to avoid a calcium-phosphate deposit on the surface of (and in) the reactor membranes: a precipitation of calcium salts by heating, a partial demineralization by electrodialysis or ion exchange, a calcium complexation by addition of sodium citrate. A continuous process for the lactose hydrolysis of milk and demineralized whey or milk ultrafiltrate was proposed. The organoleptic quality of low lactose milk, before and after heat treatment, was evaluated by a tasting panel. High sweeting syrup, were obtained by concentration of lactose hydrolyzed and demineralized ultrafiltrates. Nutritional aspects of these products are discussed specially from the toxicological point of view of galactose. PMID:101122

Roger, L; Maubois, J L; Thapon, J L; Brule, G

1978-01-01

336

Carrier-mediated Uptake of Arginine and Urea by Volvox carteri f. nagariensis  

PubMed Central

Volvox carteri f. nagariensis takes up arginine via a high affinity, highly specific carrier, whereas carriers for neutral and acidic amino acids cannot be detected (even in nitrogen-starved cultures). Exogenous arginine is accumulated against a steep concentration gradient and is incorporated into protein with high efficiency, but it is not catabolized to any significant extent and will not serve as a nitrogen source adequate to support growth. Urea is also taken up by a saturable carrier, but several lines of evidence indicate that the arginine and urea carriers are distinct and different. Preexposure to arginine suppresses arginine uptake while stimulating urea uptake. The Ki values observed for reciprocal, competitive inhibition of uptake by arginine and urea are orders of magnitude different from the respective Km values for uptake. The two uptake systems show entirely different patterns of sensitivity to inhibition by structural analogs. Finally, the Vmax values for arginine and urea uptake fluctuate independently (but in a regular pattern) during the asexual life cycle. The fluctuations of urea uptake activity are of considerable magnitude and appear to be linked to key phases of the developmental program. PMID:16660334

Kirk, Marilyn M.; Kirk, David L.

1978-01-01

337

Mechanisms of molecular transport through the urea channel of Helicobacter pylori  

PubMed Central

Helicobacter pylori survival in acidic environments relies on cytoplasmic hydrolysis of gastric urea into ammonia and carbon dioxide, which buffer the pathogen’s periplasm. Urea uptake is greatly enhanced and regulated by HpUreI, a proton-gated inner membrane channel protein essential for gastric survival of H. pylori. The crystal structure of HpUreI describes a static snapshot of the channel with two constriction sites near the center of the bilayer that are too narrow to allow passage of urea or even water. Here we describe the urea transport mechanism at atomic resolution, revealed by unrestrained microsecond equilibrium molecular dynamics simulations of the hexameric channel assembly. Two consecutive constrictions open to allow conduction of urea, which is guided through the channel by interplay between conserved residues that determine proton rejection and solute selectivity. Remarkably, HpUreI conducts water at rates equivalent to aquaporins, which might be essential for efficient transport of urea at small concentration gradients. PMID:24305683

McNulty, Reginald; Ulmschneider, Jakob P.; Luecke, Hartmut; Ulmschneider, Martin B.

2013-01-01

338

Urea biosensor based on an extended-base bipolar junction transistor.  

PubMed

In this study, a urea biosensor was prepared by the immobilization of urease onto the sensitive membrane of an extended-base bipolar junction transistor. The pH variation was used to detect the concentration of urea. The SnO2/ITO glass, fabricated by sputtering SnO2 on the conductive ITO glass, was used as a pH-sensitive membrane, which was connected with a commercial bipolar junction transistor device. The gels, fabricated by the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. This readout circuit, fabricated in a 0.35-um CMOS 2P4M process, operated at 3.3V supply voltage. This circuit occupied an area of 1.0 mm × 0.9 mm. The dynamic range of the urea biosensor was from 1.4 to 64 mg/dl at the 10 mM phosphate buffer solution and the sensitivity of this range was about 65.8 mV/pUrea. The effect of urea biosensors with different pH values was considered, and the characteristics of urea biosensors based on EBBJT were described. PMID:24211878

Sun, Tai-Ping; Shieh, Hsiu-Li; Liu, Chun-Lin; Chen, Chung-Yuan

2014-01-01

339

Mechanisms of molecular transport through the urea channel of Helicobacter pylori.  

PubMed

Helicobacter pylori survival in acidic environments relies on cytoplasmic hydrolysis of gastric urea into ammonia and carbon dioxide, which buffer the pathogen's periplasm. Urea uptake is greatly enhanced and regulated by HpUreI, a proton-gated inner membrane channel protein essential for gastric survival of H. pylori. The crystal structure of HpUreI describes a static snapshot of the channel with two constriction sites near the center of the bilayer that are too narrow to allow passage of urea or even water. Here we describe the urea transport mechanism at atomic resolution, revealed by unrestrained microsecond equilibrium molecular dynamics simulations of the hexameric channel assembly. Two consecutive constrictions open to allow conduction of urea, which is guided through the channel by interplay between conserved residues that determine proton rejection and solute selectivity. Remarkably, HpUreI conducts water at rates equivalent to aquaporins, which might be essential for efficient transport of urea at small concentration gradients. PMID:24305683

McNulty, Reginald; Ulmschneider, Jakob P; Luecke, Hartmut; Ulmschneider, Martin B

2013-01-01

340

Nitrification of archaeal ammonia oxidizers in acid soils is supported by hydrolysis of urea  

PubMed Central

The hydrolysis of urea as a source of ammonia has been proposed as a mechanism for the nitrification of ammonia-oxidizing bacteria (AOB) in acidic soil. The growth of Nitrososphaera viennensis on urea suggests that the ureolysis of ammonia-oxidizing archaea (AOA) might occur in natural environments. In this study, 15N isotope tracing indicates that ammonia oxidation occurred upon the addition of urea at a concentration similar to the in situ ammonium content of tea orchard soil (pH 3.75) and forest soil (pH 5.4) and was inhibited by acetylene. Nitrification activity was significantly stimulated by urea fertilization and coupled well with abundance changes in archaeal amoA genes in acidic soils. Pyrosequencing of 16S rRNA genes at whole microbial community level demonstrates the active growth of AOA in urea-amended soils. Molecular fingerprinting further shows that changes in denaturing gradient gel electrophoresis fingerprint patterns of archaeal amoA genes are paralleled by nitrification activity changes. However, bacterial amoA and 16S rRNA genes of AOB were not detected. The results strongly suggest that archaeal ammonia oxidation is supported by hydrolysis of urea and that AOA, from the marine Group 1.1a-associated lineage, dominate nitrification in two acidic soils tested. PMID:22592820

Lu, Lu; Han, Wenyan; Zhang, Jinbo; Wu, Yucheng; Wang, Baozhan; Lin, Xiangui; Zhu, Jianguo; Cai, Zucong; Jia, Zhongjun

2012-01-01

341

Milk production, raw milk quality and fertility of dromedary camels (Camelus Dromedarius) under intensive management.  

PubMed

In many arid countries, dromedaries play an important role as a milk source in rural areas. However, the milk and meat production potential of this species is not well understood and documented. A large-scale camel dairy farm was established in 2006 in the United Arab Emirates. This study summarises the most important data on milk production, raw milk quality and reproductive efficiency collected on this farm during the first three years of operation. The average daily milk production, the mean length of lactation and the mean total milk production per lactation of 174 dromedaries were 6.0 ± 0.12 kg (± SEM), 586 ± 11.0 days (± SEM) and 3314 ± 98.5 kg (± SEM), respectively. The lactation curve reached its peak during the 4th month after parturition (mean ± SEM, 8.9 ± 0.04 kg), then it declined gradually, falling to 50% of the maximum by the 16th month postpartum (mean ± SEM, 4.3 ± 0.06 kg). Milking three times a day did not increase daily milk production compared to two times milking. Mean total viable bacterial count (TVC) and mean somatic cell count (SCC, ± SEM) of bulk raw camel milk were 4,403 ± 94 CFU/cm3 and 392,602 ± 5,999 cells/cm3 for a one-year period, respectively. There was a significant difference among months (P < 0.001). Coliform count was < 10 CFU/cm3 in most cases (96.5%). The average (± SEM) fat, protein, lactose, total solids (TS) and solid-non-fat (SNF) concentrations of individual milk samples were 2.51 ± 0.03%, 2.60 ± 0.01%, 4.03 ± 0.03%, 9.98 ± 0.03% and 7.56 ± 0.03%, respectively. Lactation period, average daily milk production and morning vs. evening milking significantly influenced milk chemical composition. For the 470 camels in the breeding programme, end-of-season pregnancy rate and birth rate were 87.0% and 82.6%, respectively, after natural mating. We have demonstrated that sustainable milk production is possible from a traditional species, the dromedary camel, under an intensive management system. PMID:23439293

Nagy, Péter; Thomas, Sonia; Markó, Orsolya; Juhász, Jutka

2013-03-01

342

Urea-temperature phase diagrams capture the thermodynamics of denatured state expansion that accompany protein unfolding.  

PubMed

We have analyzed the thermodynamic properties of the von Willebrand factor (VWF) A3 domain using urea-induced unfolding at variable temperature and thermal unfolding at variable urea concentrations to generate a phase diagram that quantitatively describes the equilibrium between native and denatured states. From this analysis, we were able to determine consistent thermodynamic parameters with various spectroscopic and calorimetric methods that define the urea-temperature parameter plane from cold denaturation to heat denaturation. Urea and thermal denaturation are experimentally reversible and independent of the thermal scan rate indicating that all transitions are at equilibrium and the van't Hoff and calorimetric enthalpies obtained from analysis of individual thermal transitions are equivalent demonstrating two-state character. Global analysis of the urea-temperature phase diagram results in a significantly higher enthalpy of unfolding than obtained from analysis of individual thermal transitions and significant cross correlations describing the urea dependence of ?H0 and ?CP0 that define a complex temperature dependence of the m-value. Circular dichroism (CD) spectroscopy illustrates a large increase in secondary structure content of the urea-denatured state as temperature increases and a loss of secondary structure in the thermally denatured state upon addition of urea. These structural changes in the denatured ensemble make up ?40% of the total ellipticity change indicating a highly compact thermally denatured state. The difference between the thermodynamic parameters obtained from phase diagram analysis and those obtained from analysis of individual thermal transitions illustrates that phase diagrams capture both contributions to unfolding and denatured state expansion and by comparison are able to decipher these contributions. PMID:23813497

Tischer, Alexander; Auton, Matthew

2013-09-01

343

Urea-temperature phase diagrams capture the thermodynamics of denatured state expansion that accompany protein unfolding  

PubMed Central

We have analyzed the thermodynamic properties of the von Willebrand factor (VWF) A3 domain using urea-induced unfolding at variable temperature and thermal unfolding at variable urea concentrations to generate a phase diagram that quantitatively describes the equilibrium between native and denatured states. From this analysis, we were able to determine consistent thermodynamic parameters with various spectroscopic and calorimetric methods that define the urea–temperature parameter plane from cold denaturation to heat denaturation. Urea and thermal denaturation are experimentally reversible and independent of the thermal scan rate indicating that all transitions are at equilibrium and the van't Hoff and calorimetric enthalpies obtained from analysis of individual thermal transitions are equivalent demonstrating two-state character. Global analysis of the urea–temperature phase diagram results in a significantly higher enthalpy of unfolding than obtained from analysis of individual thermal transitions and significant cross correlations describing the urea dependence of and that define a complex temperature dependence of the m-value. Circular dichroism (CD) spectroscopy illustrates a large increase in secondary structure content of the urea-denatured state as temperature increases and a loss of secondary structure in the thermally denatured state upon addition of urea. These structural changes in the denatured ensemble make up ?40% of the total ellipticity change indicating a highly compact thermally denatured state. The difference between the thermodynamic parameters obtained from phase diagram analysis and those obtained from analysis of individual thermal transitions illustrates that phase diagrams capture both contributions to unfolding and denatured state expansion and by comparison are able to decipher these contributions. PMID:23813497

Tischer, Alexander; Auton, Matthew

2013-01-01

344

Toward Understanding Mechanisms Controlling Urea Delivery in a Coastal Plain Watershed  

NASA Astrophysics Data System (ADS)

Improved understanding of nutrient mobilization and delivery to surface waters is critical to protecting water quality in agricultural watersheds. Urea, a form of organic nitrogen, is a common nutrient found in fertilizers, manures, and human waste, and is gaining recognition as an important driver of coastal eutrophication, particularly through the development of harmful algal blooms. While several studies have documented elevated urea concentrations in tributaries draining to the Chesapeake Bay, little is known about the potential sources and flow pathways responsible for urea delivery from the landscape to surface waters, as well as how these sources and pathways might vary with changing seasons, antecedent conditions, and storm types. In this study, we investigated hydrologic controls on urea delivery in the Manokin River watershed through the analysis of urea concentration dynamics and hysteresis patterns during seven storm events that occurred in 2010 and 2011. The Manokin River is a Coastal Plain watershed (11.1 km2) on the Delmarva Peninsula that drains directly to the Chesapeake Bay and is characterized by extensive rural development coupled with intensive agriculture, particularly poultry production. Sampling was conducted through monthly grab sampling at baseflow conditions and by time-weighted, automated (Sigma) samplers during stormflow events. Monitored storms were chosen to represent a spectrum of antecedent conditions based on precipitation and groundwater levels in the area. Flushing from the landscape during events was found to be the predominant urea delivery mechanism, as urea concentrations increased 3-9 times above baseflow concentrations during storms. The timing and number of flushes, as well as the degree of increased concentrations were dependent on antecedent conditions and the characteristics of the storm event. For instance, during an intense (13.7 mm hr-1), short-duration (4 hrs) storm in August of 2010 when antecedent conditions were dry (5-day antecedent precipitation index = 0 mm), we observed an anticlockwise hysteresis pattern and a delayed, yet high, peak in urea concentrations (0.17 mg L-1) on the falling limb of the hydrograph. These trends suggest that urea was delivered via slow, diffuse flow pathways and from sources distal from the sampling point. In contrast, during a less intense (3.2 mm hr-1), longer duration (22 hrs) storm in October of 2010 when antecedent conditions were wetter (5-day antecedent precipitation index = 67.31 mm), we observed a clockwise hysteresis pattern and a smaller peak in urea concentrations (0.06 mg L-1) timed with the hydrograph peak. Here, the trends suggest that urea delivery occurred through faster flow pathways (e.g., shallow lateral flow) and from proximal (e.g., near-stream, in-stream) sources of urea. Collectively, these trends demonstrate that urea is flushed to streams during storm events, but that the mechanism for delivery depends on antecedent conditions, as well as the nature of the storm event.

Tzilkowski, S. S.; Buda, A. R.; Boyer, E. W.; Bryant, R. B.; May, E. B.

2012-12-01

345

Cow's milk proteins in human milk.  

PubMed

Cow's milk proteins (CMPs) are among the best characterized food allergens. Cow's milk contains more than twenty five different proteins, but only whey proteins alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin (BSA), and lactoferrin, as well as the four caseins, have been identified as allergens. Aim of this study was to investigate by proteomics techniques cow's milk allergens in human colostrum of term and preterm newborns' mothers, not previously detected, in order to understand if such allergens could be cause of sensitization during lactation. Term colostrum samples from 62 healthy mothers and preterm colostrum samples from 11 healthy mothers were collected for this purpose. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using this method, which allows direct proteins identification, beta-lactoglobulin was not detected in any of colostrum samples. According to our results bovine alpha 1 casein that is considered a major cow's milk allergen is readily secreted in human milk: further investigations are needed in order to clarify if alpha-1-casein has a major role in sensitization or tolerance to cow's milk of exclusively breastfed predisposed infants. PMID:23158513

Coscia, A; Orrù, S; Di Nicola, P; Giuliani, F; Rovelli, I; Peila, C; Martano, C; Chiale, F; Bertino, E

2012-01-01

346

Aflatoxin B? and M? in milk.  

PubMed

The aflatoxin M1 (AFLAM1) is a mycotoxin that results from the hydroxylation of the aflatoxin B1 (AFLAB1). It contaminates the milk of animals fed with a diet containing its precursor. In this work, we determined the occurrence of AFLAB1 and AFLAM1 in milk, as well as the chromatographic conditions to quantify these mycotoxins. The extraction and quantification of AFLAB1 and AFLAM1 in naturally contaminated and artificially spiked milk samples which are produced and marketed in the state of RS were performed using the AOAC official method and UHPLC with fluorescence detection. We obtained a separation factor of 2.3 for AFLAB1 and AFLAM1 using a mobile phase consisting of 1% acetic acid:acetonitrile:methanol (55:10:35). The analytical curves had a wide linearity range and the limit of quantification (LOQm) concentrations of AFLAB1 and AFLAM1 were equal to 0.5 and 0.25 ?g L(-1), respectively. Samples of pasteurized and ultra-high-temperature processed (UHT) milk showed natural contamination, and the levels for both aflatoxins ranged from 0.7 to 1.5 ?g L(-1). Raw and concentrated milk samples only contained AFLAM1, with a maximum average concentration of 1.7 ?g L(-1). These concentrations, higher than permitted by legislation, confirm the existence of a health risk, as well as highlight the relevance of searching for alternatives to reduce this contamination. PMID:24856405

Scaglioni, P T; Becker-Algeri, T; Drunkler, D; Badiale-Furlong, E

2014-06-01

347

Growth hormone and milking frequency act differently on goat mammary gland in late lactation.  

PubMed

In ruminants, milk yield can be affected by treatment with growth hormone (rbGH) and/or changes in frequency of milking. Frequent milkings encourage the maintenance of lactation, whereas infrequent milkings result in mammary involution. Our objective was to evaluate the influence of rbGH treatment and milking frequency on mammary gland morphology and milk composition. After adaptation to twice-daily milkings, six Saanen goats in late lactation were milked once daily from one udder-half and thrice-daily from the other udder-half. Concurrently, three of the six goats received daily injections of rbGH. After 23 d of treatment, milking frequency significantly affected milk yield (+8% vs. -26% for thrice- vs. once-daily milking). Additionally, treatments of rbGH increased milk yield from thrice-daily milked udder-halves (+19%), but failed to abate the reduction in milk yield from once-daily milked udder-halves (-31%). Mammary glands were heavier in the frequently milked udder-halves and in GH-treated goats. Based on histological and DNA analysis of mammary tissues, it was determined that milking frequency clearly affected epithelial cell numbers and alveolar diameter, whereas rbGH induced a potential cell hypertrophy and only a tendency to increase and/or maintain the mammary cell number. RNA concentration and kappa casein gene expression were not affected by treatments. In udder-halves milked once-daily, low casein:whey protein ratios, high Na+:K+ ratios, and high somatic cell counts (SCC) were indicative of changes in epithelial permeability, which rbGH treatment facilitated. The present data suggest that milking frequency and exogenous treatments of rbGH use different cellular mechanisms to influence mammary gland morphology and milk production. PMID:12647957

Boutinaud, M; Rousseau, C; Keisler, D H; Jammes, H

2003-02-01

348

Influence of extruded soybeans with or without bicarbonate on milk performance and fatty acid composition of goat milk.  

PubMed

The effects of extruded soybeans (ESB) included at 0, 10, or 20% of dry matter (DM) of the diet in combination with sodium bicarbonate (0 vs. 1% bicarbonate added to DM) on rumen fermentation characteristics, production parameters, and fatty acid (FA) profiles of milk fat were examined in 30 midlactation goats and 6 rumen-cannulated goats fed high-concentrate diets (30:70 forage-to-concentrate ratio) ad libitum in a 3 x 2 factorial design. Diets were fed as total mixed rations. The trial lasted 13 wk with the final 9 wk as the test period. Milk yield and composition were recorded each week throughout the trial. Individual samples of milk were taken in wk 4, 7, 10, 11, and 13 to determine FA profile of milk fat. Dry matter intake and intake of net energy for lactation were not affected by dietary treatments. Feeding ESB did not modify ruminal pH or volatile fatty acids concentration in the rumen fluid, but it increased the molar proportion of propionate. Feeding ESB increased fat-corrected milk, milk fat content, and fat yield compared with the control diets. There was no change in milk protein content when ESB were fed. Feeding ESB increased the proportions of oleic, linoleic, and linolenic acids in milk fat at the expense of most of the saturated FA. It also increased the n-6 to n-3 FA ratio of milk. The largest changes in milk yield and milk composition were generally obtained with ESB included at 20% of DM. The addition of sodium bicarbonate tended to increase ruminal pH, VFA concentrations in the rumen fluid, and the molar proportions of acetate. The addition of sodium bicarbonate increased milk fat content and fat yield, with no change in milk FA composition. It is concluded that during midlactation, the inclusion of ESB to 20% of DM prevented low milk fat content for goats fed high-concentrate diets, with no decrease in milk protein content. The addition of sodium bicarbonate may enhance the effects of ESB on milk fat content and fat yield. PMID:15653542

Schmidely, P; Morand-Fehr, P; Sauvant, D

2005-02-01

349

Impact of urea on the three-dimensional structure, viscoelastic and thermal behavior of iota-carrageenan  

PubMed Central

Urea breaks hydrogen bonds among biopolymers leading to structural destabilization. In the case of hydrocolloids urea addition is thought to impact gelation. Detailed information about its pertinent role on influencing the structure-function relationships of hydrocolloids is still elusive, however. The present investigation is aimed at delineating hydrocolloids structural behavior in the presence of urea employing iota-carrageenan as a model system. X-ray fiber diffraction, rheological and thermal properties of two iota-carrageenan solutions with weight concentrations 4.5 and 6.0% w/w at two urea molar concentrations (0.5 and 2.0 M) with and without heat treatments have been analyzed. X-ray results suggest that the canonical double helical structural arrangement of iota-carrageenan is maintained even after urea addition. However, improved crystallinity, ordering and altered unit cell dimensions especially with heat treatments of the binary mixtures indicate the promotion of favorable interactions among carrageenan helices in the presence of urea. Increased elastic modulus and onset temperature of melting endotherm with the heat treatment compared to cold addition further attests the X-ray observations of enhanced structural ordering. Overall, results suggest that urea molecules synergistically aid iota-carrageenan interactions and stabilize structure of junction zones. Our findings are deemed to be helpful in the design and development of novel non-food applications of hydrocolloids. PMID:23399231

Patel, Bhavesh K.; Campanella, Osvaldo H.; Janaswamy, Srinivas

2012-01-01

350

Impact of urea on the three-dimensional structure, viscoelastic and thermal behavior of iota-carrageenan.  

PubMed

Urea breaks hydrogen bonds among biopolymers leading to structural destabilization. In the case of hydrocolloids urea addition is thought to impact gelation. Detailed information about its pertinent role on influencing the structure-function relationships of hydrocolloids is still elusive, however. The present investigation is aimed at delineating hydrocolloids structural behavior in the presence of urea employing iota-carrageenan as a model system. X-ray fiber diffraction, rheological and thermal properties of two iota-carrageenan solutions with weight concentrations 4.5 and 6.0% (w/w) at two urea molar concentrations (0.5 and 2.0 M) with and without heat treatments have been analyzed. X-ray results suggest that the canonical double helical structural arrangement of iota-carrageenan is maintained even after urea addition. However, improved crystallinity, ordering and altered unit cell dimensions especially with heat treatments of the binary mixtures indicate the promotion of favorable interactions among carrageenan helices in the presence of urea. Increased elastic modulus and onset temperature of melting endotherm with the heat treatment compared to cold addition further attests the X-ray observations of enhanced structural ordering. Overall, results suggest that urea molecules synergistically aid iota-carrageenan interactions and stabilize structure of junction zones. Our findings are deemed to be helpful in the design and development of novel non-food applications of hydrocolloids. PMID:23399231

Patel, Bhavesh K; Campanella, Osvaldo H; Janaswamy, Srinivas

2013-02-15

351

Supplementation of zero-grazed dairy cows with molassed sugar beet pulp, maize or a cereal-rich concentrate  

Microsoft Academic Search

Experiments were carried out to investigate the effects of different carbohydrate sources on food intake, milk yield, composition of the milk and its urea content. The experimental design was a complete randomised block with four treatments per block. The treatments were: herbage only (OS), herbage plus molassed sugar beet pulp (MSB), herbage plus maize (M) and herbage plus a mixture

F. J. Schwarz; J. Haffner; M. Kirchgessner

1995-01-01

352

Good Milk for Good Meals.  

E-print Network

is made safe since all harmful bacteria are destroyed, and its keeping qualities are improved. It changes the food value very little. Homogenized milk is pasteurized whole milk which has been treated mechanically to break up fat globules. The fat... no longer forms a cream layer but stays distributed throughout the milk. The homogenization process does not change the composition, but the milk is digested more easily and is more palatable. Skim milk is milk from which practically all cream has been...

Hutchison, J. E.

1960-01-01

353

Nitrogen balance, microbial protein production, and milk production in dairy cows fed fodder beets and potatoes, or barley.  

PubMed

Fourteen multiparous midlactation dairy cows were used in a change-over experiment with 3 periods and 3 diets to evaluate the effects of fodder beets and potatoes on N metabolism, microbial protein production, and milk production. A basal ration of alfalfa/grass silage offered ad libitum, 1 kg of grass hay and 1 kg of heat-treated rapeseed cake was supplemented with 5 kg DM of either rolled barley/raw potatoes 80:20 (BAP), fodder beets/raw potatoes 80:20 (BEP) or rolled barley (BA). Urine and feces were collected quantitatively from 8 cows and ruminal samplings, and evacuations were performed on 4 cannulated cows. Intake and production did not differ between BAP and BA, but the BEP diet lowered intake of both silage and total ration by 0.9 kg DM. Daily yield of energy-corrected milk (ECM) was decreased by 1.7 and 2.3 kg compared with BAP and BA, respectively. Milk urea concentration was 1 mM lower with the BEP diet. The proportion of feed N recovered in milk was 20 to 21% for all diets. With the BEP diet, urinary N amount and proportion were reduced correspondingly to the lower total N intake. Fecal N amount remained unchanged, and hence nitrogen apparent digestibility decreased by 5 percentage units with the BEP diet. Microbial protein production, assessed by allantoin excretion, tended to be highest with the BAP diet. Acetate proportion of VFA was lowered by the BEP diet, while proportions of propionate and butyrate both tended to increase. Different fermentation patterns, probably related to differences in rumen microbiota, could explain why changes in energetic efficiency and milk composition reported in the literature did not occur in the actual experiment when roots replaced barley. Compared with barley, roots appeared to have a greater negative effect on silage intake in conjunction with a prewilted silage with high intake potential allowed ad libitum and this decreased milk production by a magnitude corresponding to the lower intake of ME. PMID:15259242

Eriksson, T; Murphy, M; Ciszuk, P; Burstedt, E

2004-04-01

354

POLYBROMINATED DIPHENYL ETHERS (PBDES) IN AMERICAN MOTHERS' MILK  

EPA Science Inventory

No previous reports exist on polybrominated diphenyl ether (PBDE) congeners in individual American mothers' milk. This report on PBDEs is an extension of our previous studies on concentrations of dioxins, dibenzofurans, PCBs, and other chlorinated organics in human milk in a num...

355

Innovations in Indian Fermented Milk Products — A Review  

Microsoft Academic Search

Dahi is considered the oldest Indian fermented milk product and is equivalent to Western yogurt from which derivatives such as shrikhand (sweetened concentrated curd) and lassi (stirred curd) are derived. Dietetic significance of Indian fermented milk products has been established due to its various nutritional and therapeutic properties. Acceptable quality dahi could be obtained with the application of acid producing

S. Sarkar

2008-01-01

356

On-line measurement of urea in blood using optical spectroscopy in the visible range; Validation of the cell shrinkage hypothesis  

Microsoft Academic Search

The present work shows the development of a low-cost system to measure on-line blood urea concentration during hemodialysis procedures using optical spectroscopy in the visible range. Dissolved urea presents absorbance in the infrared, not showing any significant optical behavior in the visible range. Nevertheless, previous results obtained by the first author in Mexico displayed experimental evidence of a clear correlation

G. A. Martinez; R. Bragos

2004-01-01

357

Infant formula and infant nutrition: bioactive proteins of human milk and implications for composition of infant formulas.  

PubMed

Human milk contains an abundance of biologically active components that are highly likely to contribute to the short- and long-term benefits of breastfeeding. Many of these components are proteins; this article describes some of these proteins, such as ?-lactalbumin, lactoferrin, osteopontin, and milk fat globule membrane proteins. The possibility of adding their bovine counterparts to infant formula is discussed as well as the implications for infant health and development. An important consideration when adding bioactive proteins to infant formula is that the total protein content of formula needs to be reduced, because formula-fed infants have significantly higher concentrations of serum amino acids, insulin, and blood urea nitrogen than do breastfed infants. When reducing the protein content of formula, the amino acid composition of the formula protein becomes important because serum concentrations of the essential amino acids should not be lower than those in breastfed infants. Both the supply of essential amino acids and the bioactivities of milk proteins are dependent on their digestibility: some proteins act only in intact form, others act in the form of larger or small peptides formed during digestion, and some are completely digested and serve as a source of amino acids. The purity of the proteins or protein fractions, potential contaminants of the proteins (such as lipopolysaccharide), as well as the degree of heat processing used during their isolation also need to be considered. It is likely that there will be more bioactive components added to infant formulas in the near future, but guidelines on how to assess their bioactivities in vitro, in animal models, and in clinical studies need to be established. The extent of testing needed is likely going to depend on the degree of complexity of the components and their bioequivalence with the human compounds whose effects they are intended to mimic. PMID:24452231

Lönnerdal, Bo

2014-03-01

358

Fat Separation in Evaporated Milk I. Homogenization, Separation, and Viscosity Tests1  

Microsoft Academic Search

The rising of fat in evaporated milk on prolonged storage will inevitably occur since the density of the fat particles is lower than that of the concentrated milk plasma in which they are suspended. It has been shown that the velocity of rise of individual fat globules in milk plasma is in good agreement with the velocity as predicated by

R. B. Maxcy; H. H. Sommer

1954-01-01

359

Effects on milk yield and composition of infusions of volatile fatty acids and caseinate into  

E-print Network

Effects on milk yield and composition of infusions of volatile fatty acids and caseinate Laitière, Saint-Gilles, 35590 L'Hermitage, France Changes in milk secretion and composi- tion, particularly concentrate and 7.5% soya bean meal. Duodenal infusion of casein increased milk yield (+ 1.9 kg

Paris-Sud XI, Université de

360

Stability of aflatoxin M in milk.  

PubMed

This three-part study was designed to determine aflatoxin M recovery from pasteurized and/or stored cow's milk. (a) Aflatoxin M was added to samples of raw Holstein milk at a concentration of 2.0 mug/liter. Half of each sample then was pasteurized at 63 C for 30 min, and both raw and pasteurized portions were stored at 4 C up to 17 days. (b) Samples of raw milk, pasteurized (77 C, 16 s) skim milk, dry cottage cheese curd, and cottage cheese whey were taken from a commercial operation in an area in which natural contamination had been encountered. (c) Milk from a cow dosed with aflatoxin B1 was stored frozen (-18 C) in bulk and in assay-size sample containers for 120 days. Aflatoxin M was recovered completely after either storage or pasteurization in (a) and (b). In (c), a recovery deficiency was detectable after 68 days of storage, which increased to 45% of the original value by 120 days. These observations differ from those of others in that loss of aflatoxin M was significant after pasteurization or storage of raw milk, totaling 87% loss after 120 days of frozen storage. Aflatoxin M partitioning between curd and whey in the preparation of cottage cheese agrees with more recent studies, but differs from previous reports. Three possible explanations for the differences are offered. PMID:1239463

Stoloff, L; Trucksess, M; Hardin, N; Francis, O J; Hayes, J R; Polan, C E; Campbell, T C

1975-12-01

361

Voltammetric Detection of Urea on an Ag-Modified Zeolite-Expanded Graphite-Epoxy Composite Electrode  

PubMed Central

In this paper, a modified expanded graphite composite electrode based on natural zeolitic volcanic tuff modified with silver (EG-Ag-Z-Epoxy) was developed. Cyclic voltammetry measurements revealed a reasonably fast electron transfer and a good stability of the electrode in 0.1 M NaOH supporting electrolyte. This modified electrode exhibited moderate electrocatalytic effect towards urea oxidation, allowing its determination in aqueous solution. The linear dependence of the current versus urea concentration was reached using square-wave voltammetry in the concentrations range of urea between 0.2 to 1.4 mM, with a relatively low limit of detection of 0.05 mM. A moderate enhancement of electroanalytical sensitivity for the determination of urea at EG-Ag-Z-Epoxy electrode was reached by applying a chemical preconcentration step prior to voltammetric/amperometric quantification.

Manea, Florica; Pop, Aniela; Radovan, Ciprian; Malchev, Plamen; Bebeselea, Adriana; Burtica, Georgeta; Picken, Stephen; Schoonman, Joop

2008-01-01

362

Decoding breast milk oligosaccharides.  

PubMed

Oligosaccharides represent a significant fraction of breast milk, reaching up to 20 g/l in early milk. Human milk oligosaccharides comprise close to 200 structures, which are not absorbed by the intestinal tissue and have no nutritional value for the breastfed infant. Early studies conducted around 1930 already attributed a prebiotic activity to milk oligosaccharides by showing their stimulatory effects on the growth of specific intestinal microbiota. In addition, milk oligosaccharides contribute to the defence against enteric pathogens by acting as soluble decoys preventing the adhesion of viruses and bacteria to their carbohydrate mucosal receptors. The structural complexity of milk oligosaccharides hampers the assignment of specific functions to single carbohydrates. The application of mouse models allows the investigation of unique milk oligosaccharides in the context of intestinal microbiota and mucosal immunity. In this respect, our recent work has demonstrated that uptake of the milk oligosaccharide 3-sialyllactose increases the inflammatory response observed in different colitis models. The proinflammatory action of 3-sialyllactose was attributed on the one hand to the modulation of intestinal bacterial groups, and on the other hand to a direct stimulatory effect on CD11c+ dendritic cells. The availability of pure oligosaccharides in large amounts will soon enable the study of these compounds in humans in the context of intestinal and metabolic disorders associated to various forms of dysbiosis. PMID:24554478

Hennet, Thierry; Weiss, Adrienne; Borsig, Lubor

2014-01-01

363

Whole Milk Reverse Osmosis Retentates for Cheddar Cheese Manufacture: Cheese Composition and Yield  

Microsoft Academic Search

The impact of concentrating whole milk by reverse osmosis prior to Cheddar cheese making was studied. Heat treated, standardized, whole milk was reduced in volume by 0, 5, 10, 15, and 20% prior to Cheddar cheese manufacture. Milk solids at various milk volume reductions were 11.98, 12.88, 13.27, 14.17, and 15.05%, respectively. Permeates contained only traces of organic matter and

D. M. Barbano; D. G. Bynum

1984-01-01

364

Evaluation of Five Screening Tests Used for Estimating Leucocyte Counts in Bulk Milk1  

Microsoft Academic Search

l~ive screening tests, Direct Microscopic Leucocyte Count, Wisconsin Mastitis Test, California Mastitis Test, Clemson Cata- lase Test, Wisconsin Catalase Test, used in estimating leucocyte concentrations were evaluated using 1,308 producer milk samples and 97 tank-delivered samples. These milk samples were representative of the South Carolina milk supply. The Wisconsin test was the most reliable method for estimating leucocytes in milk,

J. J. Janzen

1969-01-01

365

Testing the ability of non-methylamine osmolytes present in kidney cells to counteract the deleterious effects of urea on structure, stability and function of proteins.  

PubMed

Human kidney cells are under constant urea stress due to its urine concentrating mechanism. It is believed that the deleterious effect of urea is counteracted by methylamine osmolytes (glycine betaine and glycerophosphocholine) present in kidney cells. A question arises: Do the stabilizing osmolytes, non-methylamines (myo-inositol, sorbitol and taurine) present in the kidney cells also counteract the deleterious effects of urea? To answer this question, we have measured structure, thermodynamic stability (?G D (o)) and functional activity parameters (K m and k cat) of different model proteins in the presence of various concentrations of urea and each non-methylamine osmolyte alone and in combination. We observed that (i) for each protein myo-inositol provides perfect counteraction at 1?2 ([myo-inositol]:[urea]) ratio, (ii) any concentration of sorbitol fails to refold urea denatured proteins if it is six times less than that of urea, and (iii) taurine regulates perfect counteraction in a protein specific manner; 1.5?2.0, 1.2?2.0 and 1.0?2.0 ([taurine]:[urea]) ratios for RNase-A, lysozyme and ?-lactalbumin, respectively. PMID:24039776

Khan, Sheeza; Bano, Zehra; Singh, Laishram R; Hassan, Md Imtaiyaz; Islam, Asimul; Ahmad, Faizan

2013-01-01

366

Testing the Ability of Non-Methylamine Osmolytes Present in Kidney Cells to Counteract the Deleterious Effects of Urea on Structure, Stability and Function of Proteins  

PubMed Central

Human kidney cells are under constant urea stress due to its urine concentrating mechanism. It is believed that the deleterious effect of urea is counteracted by methylamine osmolytes (glycine betaine and glycerophosphocholine) present in kidney cells. A question arises: Do the stabilizing osmolytes, non-methylamines (myo-inositol, sorbitol and taurine) present in the kidney cells also counteract the deleterious effects of urea? To answer this question, we have measured structure, thermodynamic stability (?GDo) and functional activity parameters (Km and kcat) of different model proteins in the presence of various concentrations of urea and each non-methylamine osmolyte alone and in combination. We observed that (i) for each protein myo-inositol provides perfect counteraction at 1?2 ([myo-inositol]:[urea]) ratio, (ii) any concentration of sorbitol fails to refold urea denatured proteins if it is six times less than that of urea, and (iii) taurine regulates perfect counteraction in a protein specific manner; 1.5?2.0, 1.2?2.0 and 1.0?2.0 ([taurine]:[urea]) ratios for RNase-A, lysozyme and ?-lactalbumin, respectively. PMID:24039776

Khan, Sheeza; Bano, Zehra; Singh, Laishram R.; Hassan, Md. Imtaiyaz; Islam, Asimul; Ahmad, Faizan

2013-01-01

367

Solute rejection by porous glass membranes. I - Hyperfiltration of sodium chloride and urea feed solutions.  

NASA Technical Reports Server (NTRS)

Hyperfiltration of sodium chloride and urea was studied with porous glass membranes in closed-end capillary form, to determine the effect of pressure, temperature, and concentration variations, and lifetime rejection and flux characteristics. Rejection data for sodium chloride were consistent with the functioning of the porous glass as a low-capacity ion-exchange membrane.

Ballou, E. V.; Wydeven, T.; Leban, M. I.

1971-01-01

368

Guanidinosuccinic Acid on Human Platelet Effects of Exogenous Urea, Creatinine, and Aggregation In Vitro  

Microsoft Academic Search

a bleeding tendency associated with a prolonged bleeding time and an ade- quate platelet count. We have tested the effectson plateletaggregation of three compounds that are found in in- creased concentration in the blood of patients with renal failure. The addi- tion of urea was followed by an imme- diate, but transient, increase in optical density of platelet-rich plasma. This

James W. Davis; James R. McField; Phyllis E. Phillips; Barbara A. Graham

369

Carbohydrate and Amino Acid Metabolism in Lambs Fed Purified Diets Containing Urea or Isolated Soy Protein  

Microsoft Academic Search

A purified basal diet was pair-fed to five sets of twin lambs for comparing the effects of soybean protein (SP) or urea (U) on liver, heart, kidney, plasma and urinary concentrations of amino acids, metabolic intermediates and other constituents. Feed was available from 8 to 10 AMand 1 to 3 PM daily dur ing the entire feeding period of 76

R. L. PRIOR; J. A. MILNER; ANDW. J. VISEK

370

Detailed modeling of the evaporation and thermal decomposition of urea-water-solution in SCR systems  

E-print Network

-water-solution (UWS) is sprayed into the hot engine exhaust upstream of the SCR catalyst. It is commonly believed of urea concentration inside the droplet during the evaporation process. The effects of solute droplets (composed of water and zirconium acetate) axially injected into plasma. As water evaporates

Boyer, Edmond

371

Kinetic analysis of urea-inactivation of beta-galactosidase in the presence of galactose.  

PubMed

The effect of galactose on the inactivation of purified beta-galactosidase from the black bean, Kestingiella geocarpa, in 5 M urea at 50 degrees C and at pH 4.5, was determined. Lineweaver-Burk plots of initial velocity data in the presence and absence of urea and galactose were used to determine the relevant K(m) and V(max) values, with p-nitrophenyl beta-D-galactopyranoside (PNPG) as substrate, S. The inactivation data were analysed using the Tsou equation and plots. Plots of ln([P](infinity) - [P](t) ) against time in the presence of urea yielded the inactivation rate constant, A. Plots of A vs [S] at different galactose concentrations were zero order showing that A was independent of [S]. Plots of [P](infinity) vs [S] were used to determine the mode of inhibition of the enzyme by galactose, and slopes and intercepts of the 1/[P](infinity) vs. 1/[S] yielded k(+0) and k '(+0), the microscopic rate constants for the free enzyme and the enzyme-substrate complex, respectively. Plots of k(+0) and k '(+0) vs. galactose concentrations showed that galactose protected the free enzyme and not the enzyme-substrate complex against urea inactivation via a noncompetitive mechanism at low galactose concentrations and a competitive pattern of inhibition at high galactose concentrations. The implication of the different modes of inhibition in protecting the free enzyme was discussed. PMID:18341246

Chilaka, Ferdinand C; Nwamba, Charles O

2008-02-01

372

Urea: a comprehensive review of the clinical literature  

E-print Network

effect of salicylic acid and urea in human skin. Skinsalicylic acid alone CT Single 4-hour application on back skinsalicylic acid ointment, and paraffin-based moisturizers [17]. The beneficial effects of urea on ichthyotic skin

Pan, Michael; Heinecke, Gillian; Bernardo, Sebastian; Tsui, Cindy; Levitt, Jacob

2013-01-01

373

Aldehyde-containing urea-absorbing polysaccharides  

NASA Technical Reports Server (NTRS)

A novel aldehyde containing polymer (ACP) is prepared by reaction of a polysaccharide with periodate to introduce aldehyde groups onto the C2 - C3 carbon atoms. By introduction of ether and ester groups onto the pendant primary hydroxyl solubility characteristics are modified. The ACP is utilized to absorb nitrogen bases such as urea in vitro or in vivo.

Mueller, W. A.; Hsu, G. C.; Marsh, H. E., Jr. (inventors)

1977-01-01

374

Influence of Land Management and Hydrology on Urea Fate and Transport Within a Coastal Plain Watershed Dominated by Intensive Poultry Agriculture  

NASA Astrophysics Data System (ADS)

Increasing nutrient loads delivered from the landscape to coastal ecosystems has widely been recognized as a major contributor to coastal eutrophication and as a driver of the escalation of harmful algal blooms (HABs). Urea, a form of organic nitrogen, is a common nutrient found in fertilizers, manures, and septic waste, and is gaining recognition as a preferred nutrient for the development of toxic HABs. While several studies have documented elevated urea concentrations in tributaries draining the Delmarva Peninsula and in the Chesapeake Bay, little is known about the key factors that influence urea delivery from the landscape to surface waters. Here, in attempt to address the need to better understand urea behavior, we investigated land management and hydrologic controls on urea loss, both spatially and temporally, in the Manokin River. The Manokin River is a Coastal Plain watershed (300 km2) on the Delmarva Peninsula that drains directly to the Chesapeake Bay and is characterized by extensive rural development coupled with intensive agriculture, particularly poultry production. Monthly synoptic sampling during baseflow conditions was conducted throughout the watershed in order to represent the variety of potential point and non-point sources of urea. Sampling was also conducted during stormflow conditions using time-weighted automated (SIGMA) samplers at select sites within the watershed. Temporal baseflow trends illustrate higher average urea concentrations through the summer months (0.61 ?M L-1) and generally lower (0.35 ?M L-1) concentrations during the winter months. Spatial trends show higher average baseflow urea concentrations in the agricultural ditches and headwaters (0.93?M L-1) with decreasing concentrations moving downstream (0.37 ?M L-1). Stormflow was found to be the predominant urea delivery mechanism, as urea concentrations typically increased 3-9 times above baseflow concentrations (0.27 ?M L-1) during storms, with peaks in urea concentration generally following peaks in discharge. Results from this study will be used to determine whether there is a link between urea delivery from the Manokin River and harmful algal blooms in the Chesapeake Bay as well as to guide the development of best management practices to control urea loss from agricultural activities.

Gustafson, S. S.; Buda, A. R.; Boyer, E. W.; Bryant, R.; May, E.

2011-12-01

375

User-defined serum aspartate and alanine aminotransferase, cholesterol, triglycerides, urea, and uric acid for the Beckman synchron CX 4/5 using Ames Sera-Pak reagents.  

PubMed

Beckman aspartate aminotransferase (AST), alanine aminotransferase (ALT), cholesterol, triglycerides, urea, and uric acid Liquid Reagents for Synchron CX 4/5 (48, 48, 25, 60, 26, and 30 cents US/test, respectively) are expensive. We have established our own methods for serum AST, ALT, cholesterol, triglycerides, urea, and uric acid (6, 6, 5, 12, 13, and 6 cents US/test, respectively) using Ames Sera-Pak reagents. Linearity of our AST, ALT, cholesterol, triglycerides, urea, and uric acid methods were either similar to or higher than the Beckman methods. The within run and day-to-day run precisions were acceptable. Recovery of our AST, ALT, cholesterol, triglycerides, urea, and uric acid were excellent. Our results for AST, ALT, cholesterol, triglycerides, urea, and uric acid correlated well with the Beckman results. Bilirubin (340.8 mumol/L) did not significantly interfere on our AST, ALT, cholesterol, triglycerides, and urea, while its concentrations of 165.8 mumol/L started giving negative interference on uric acid. Turbidity (2+) did not interfere significantly on our AST and ALT but started giving positive interference on cholesterol, triglycerides, urea, and uric acid. Hemolysis (2+) gave positive interference on our cholesterol, triglycerides, urea, and uric acid. Stability of Ames Sera-Pak working reagents was at least 30 days for AST, ALT, urea, and uric acid and 40 days for cholesterol and triglycerides. PMID:1403344

Lolekha, P H; Nitipaichit, P

1992-01-01

376

Phenol–urea–formaldehyde (PUF) co-condensed wood adhesives  

Microsoft Academic Search

The reaction of urea with methylolphenol under acidic conditions was investigated. The alternating copolymer of urea and phenol could be synthesized by the reaction of urea and 2,4,6-trimethylolphenol. The reactions of urea with polymethylolphenol mixtures also were investigated by changing the reaction conditions, such as the molar ratio and acidity. The co-condensates were analysed by carbon-13 nuclear magnetic resonance spectroscopy

Bunichiro Tomita; Chung-Yun Hse

1998-01-01

377

New spectrophotometric estimation of ornidazole tablets employing urea as a hydrotropic solubilizing additive.  

PubMed

Quantitative spectrophotometric analysis of poorly water-soluble drugs involves use of various organic solvents. Major drawbacks of organic solvents include high cost, volatility and toxicity. Safety of analyzer is affected by toxicity of the solvent used. In the present investigation the use of organic solvent has been avoided, making the method environmentally friendly. Urea has demonstrated enhancement in aqueous solubilities of a large number of poorly water-soluble drugs, thereby widely used as a hydrotropic agent. There was more than 10-fold enhancement in the solubility of ornidazole in 10 M urea solution as compared to its solubility in distilled water. In the present investigation, hydrotropic solution of urea (10 M) was employed as solubilizing agent to solubilize the poorly water-soluble drug, ornidazole, from fine powder of its tablet dosage form for spectrophotometric determination in ultraviolet region at 319 nm. Beer's law was obeyed in the concentration range of 5-25 ?g/ml in presence of urea. Presence of urea did not interfere in the analysis. Proposed method is new, rapid, simple, accurate, and reproducible. Statistical data proved the accuracy, reproducibility and the precision of the proposed method. PMID:20838537

Maheshwari, R K; Srivastav, V K; Prajapat, R P; Jain, Anshu; Kamaria, P; Sahu, S

2010-03-01

378

Selective catalytic reduction of NO{sub 2} with urea in nanocrystalline NaY zeolite  

SciTech Connect

In this study, the selective catalytic reduction (SCR) of NO{sub 2} with urea in nanocrystalline NaY zeolite was investigated with in situ transmission Fourier transform infrared (FTIR) spectroscopy and solid-state nuclear magnetic resonance spectroscopy. At T=473 K, the reaction rate for urea-SCR of NO{sub 2} in nanocrystalline NaY zeolite was significantly greater than that in commercial NaY zeolite with a larger crystal size. In addition, a dramatic decrease in the concentration of undesirable surface species, including biuret and cyanuric acid, was observed in nanocrystalline NaY compared with commercial NaY after urea-SCR of NO{sub 2} at T=473 K. The increased reactivity for urea-SCR of NO{sub 2} was attributed to silanol groups and extra-framework aluminum species located on the external surface of nanocrystalline NaY. Specifically, NOx storage as nitrate and nitrite on the internal zeolite surface was coupled to reactive deNOx sites on the external surface. Isotopic labeling combined with IR analysis suggest that NN bond formation involved both an N-atom originating from NO{sub 2} and an N-atom originating from urea. This is the first clear example demonstrating that the increased external surface area (up to 40% of total surface area) of nanocrystalline zeolites can be used as a reactive surface with unique active sites for catalysis.

Gonghu Li; Conrad A. Jones; Vicki H. Grassian; Sarah C. Larsen [University of Iowa, Iowa City, IA (United States). Department of Chemistry

2005-09-10

379

Saturable urea transport pathway across the urinary bladder of Bufo viridis and salt acclimation.  

PubMed

Urea fluxes across the urinary bladder of Bufo viridis were studied in vitro after modification of the mounting technique. The fluxes increased as a function of the bath urea concentration, saturating near 200 mmol/l. The apparent Km was 88 mmol/l in the bladders from tapwater-acclimated toads, and 107 mmol/l in toads acclimated to 500 mOsm NaCl. The Vmax which was 300 mumol.h-1.cm-2 at room temperature in bladders from tapwater acclimation, changed to more than 1500 mumol.h-1.cm-2 upon salt acclimation. It is suggested that urea movement across the urinary bladder of this species occurs by facilitated diffusion and that salt acclimation induces an increase in the density of this pathway, but not of its characteristics (Km). PMID:2804458

Shpun, S; Katz, U

1989-01-01

380

76 FR 15339 - Solid Urea From Russia and Ukraine  

Federal Register 2010, 2011, 2012, 2013

...731-TA-340-E and 340-H (Third Review)] Solid Urea From Russia and Ukraine AGENCY: United...concerning the antidumping duty orders on solid urea from Russia and Ukraine...revocation of the antidumping duty orders on solid urea from Russia and Ukraine would be...

2011-03-21

381

76 FR 77015 - Solid Urea From Russia and Ukraine  

Federal Register 2010, 2011, 2012, 2013

...340-E and 340-H (Third Review)] Solid Urea From Russia and Ukraine Determination...revocation of the antidumping duty orders on solid urea from Russia and Ukraine would be likely...Publication 4279 (December 2011), entitled Solid Urea from Russia and Ukraine:...

2011-12-09

382

75 FR 74746 - Solid Urea From Russia and Ukraine  

Federal Register 2010, 2011, 2012, 2013

...731-TA-340-E and 340-H (Third Review)] Solid Urea From Russia and Ukraine AGENCY: United...concerning the antidumping duty orders on solid urea from Russia and Ukraine...revocation of the antidumping duty orders on solid urea from Russia and Ukraine would be...

2010-12-01

383

MICROWAVE-ASSISTED PREPARATION OF CYCLIC UREAS FROM DIAMINES  

EPA Science Inventory

Rajender S. Varma* and Yong-Jin Kim Cyclic ureas are useful intermediates for a variety of pharmaceuticals and pesticides. One of the attractive approaches for the synthesis of cyclic ureas uses condensation of diamines with urea as a carbonyl source under dynamic evacuation. ...

384

Determination of ivermectin and moxidecin residues in bovine milk and examination of the effects of these residues on acid fermentation of milk.  

PubMed

Ivermectin (IVM) and moxidectin (MXD) are broad-spectrum antiparasitic drugs not approved for use in dairy animals, although their use in dairy sheep, goats and cattle nevertheless occurs in many parts of the world. The work reported here describes (1) the application of an HPLC method (including milk samples clean-up and chemical extraction) to quantify IVM and MXD residues in bovine milk, and (2) an assessment of the effect of different IVM and MXD concentrations on bovine milk acid fermentation. The latter was carried out using the 'yoghurt test' to determine the minimum IVM and MXD concentrations affecting milk acid fermentation. The sample clean-up, chemical extraction and the validated HPLC method allowed the quantification of IVM and MXD up to 0.1 ng ml(-1) in milk with acceptable validation coefficients. Drug recoveries from fortified milk samples ranged between 72% (CV = 9.1%) and 75% (CV = 13.3%) for MXD and IVM, respectively. Neither IVM nor MXD affected the acid fermentation of bovine milk. In fact, there was no drug-induced changes on milk acidity even at IVM and MXD concentrations as high as 1000 ng ml(-1). These results indicate that the yoghurt biological test is not suitable to evaluate the presence of milk residues for these antiparasitic compounds. Thus, a highly sensitive HPLC technique is the only reliable method for determining the presence of residual concentrations of IVM and MXD in milk and dairy products to assure consumer safety. PMID:12396392

Imperiale, F; Sallovitz, J; Lifschitz, A; Lanusse, C

2002-09-01

385

Mid-infrared spectrometry of milk for dairy metabolomics: a comparison of two sampling techniques and effect of homogenization.  

PubMed

Milk production is a dominant factor in the metabolism of dairy cows involving a very intensive interaction with the blood circulation. As a result, the extracted milk contains valuable information on the metabolic status of the cow. On-line measurement of milk components during milking two or more times a day would promote early detection of systemic and local alterations, thus providing a great input for strategic and management decisions. The objective of this study was to investigate the potential of mid-infrared (mid-IR) spectroscopy to measure the milk composition using two different measurement modes: micro attenuated total reflection (?ATR) and high throughput transmission (HTT). Partial least squares (PLS) regression was used for prediction of fat, crude protein, lactose and urea after preprocessing IR data and selecting the most informative wavenumber variables. The prediction accuracies were determined separately for raw and homogenized copies of a wide range of milk samples in order to estimate the possibility for on-line analysis of the milk. In case of fat content both measurement modes resulted in an excellent prediction for homogenized samples (R(2)>0.92) but in poor results for raw samples (R(2)<0.70). Homogenization was however not mandatory to achieve good predictions for crude protein and lactose with both ?ATR and HTT, and urea with ?ATR spectroscopy. Excellent results were obtained for prediction of crude protein, lactose and urea content (R(2)>0.99, 0.98 and 0.86 respectively) in raw and homogenized milk using ?ATR IR spectroscopy. These results were significantly better than those obtained by HTT IR spectroscopy. However, the prediction performance of HTT was still good for crude protein and lactose content (R(2)>0.86 and 0.78 respectively) in raw and homogenized samples. However, the detection of urea in milk with HTT spectroscopy was significantly better (R(2)=0.69 versus 0.16) after homogenization of the milk samples. Based on these observations it can be concluded that ?ATR approach is most suitable for rapid at line or even on-line milk composition measurement, although homogenization is crucial to achieve good prediction of the fat content. PMID:21962352

Aernouts, Ben; Polshin, Evgeny; Saeys, Wouter; Lammertyn, Jeroen

2011-10-31

386

Effect of Squestering Agents on Aflatoxin in Milk of Dairy Cows Fed Aflatoxin-contaminated Diets.  

E-print Network

??Three experiments (EXP) were conducted to determine the potential of experimental sequestering agents, clays or non-digestible yeast oligosaccharides, to reduce milk aflatoxin concentration in lactating… (more)

Waltman, Lindsey

2008-01-01

387

A survey of vitamin A and D contents of fortified fluid milk in Ontario.  

PubMed

High performance liquid chromatographic methods for measuring the concentration of vitamins A and D in fluid milk were validated and used to assess the level of these nutrients in Ontario retail milk samples. Thirteen and fifteen fortified milk samples were tested for vitamins A and D, respectively. Repeatability relative standard deviation values for vitamins A and D in milk were generally less than 10%. Recoveries varied from 87 to 107%. Vitamin D results indicated that only 20% of skim, 40% of 2% fat milk, and 20% of whole milk contained the recommended levels, whereas 46% of skim, and 77% of 2% fat milk had the required levels of vitamin A. The results indicate that vitamin level varies widely in Ontario retail milk. PMID:10877385

Faulkner, H; Hussein, A; Foran, M; Szijarto, L

2000-06-01

388

Multinational study of major breast milk carotenoids of healthy mothers  

Microsoft Academic Search

Summary.   Background: Carotenoids in serum vary between countries and within populations with evidence suggesting a qualitative relationship to\\u000a diet. Breast milk carotenoids furnish a source of vitamin A and potentially provide immunoprotection and other health benefits\\u000a for infants. There have been numerous studies of milk carotenoid concentrations in undernourished populations; however, carotenoid\\u000a concentrations have not previously been compared in populations

Louise M. Canfield; M. Thomas Clandinin; David P. Davies; Maria C. Fernandez; Joan Jackson; Jo Hawkes; William J. Goldman; Kathryn Pramuk; Horacio Reyes; Benjamin Sablan; Tomoyoshi Sonobe; Xu Bo

2003-01-01

389

An in vitro digestibility study on human milk and related proteins used in infant formula  

E-print Network

) clearly identified two casein subunits as 8- and k-caseins, representing 64% and 27% of the total casein content in human milk. They also determined that the remaining 95 corresponds to a fraction high in phosphorous that migrates quickly in acrylamide... (Greenberg et al. , 1984). The presence of a 7 -casein subunit in human milk was studied by Nagasawa et al. (1967). This component showed the slowest mobility in AGUE (acrylamide-gel-electrophoresis in the presence of urea) (Nagasawa et al. , 1967...

Vethencourt-Petrini, Adriana Coromoto

2012-06-07

390

Cow's milk and children  

MedlinePLUS

... 2 cup milk, yogurt, pudding 3/4 oz. cheese 1 cup cottage cheese Teens and adults also need plenty of dairy ... to three servings of 1 ½ oz. natural cheese per day Four servings of 2 oz. processed ...

391

Simulating the effect of exercise on urea clearance in hemodialysis.  

PubMed

A two-compartment model of urea kinetics during hemodialysis is used to predict the effect of exercise on hemodialysis dose. It is assumed that the two compartments represent tissues that are perfused by low and high blood flows (initially 1.1 L/min and 3.8 L/min). The effect of changing the distribution of flows between the compartments, emulating the effect of exercise, is simulated using the model equations for a range of dialyzer clearances. Compartmental volumes are assumed constant (33.4 L and 8.6 L for low- and high-flow compartments, respectively). The analysis identifies muscle perfusion as a rate-limiting factor during the later stages of hemodialysis and illustrates the benefit of exercise during this phase in increasing dialysis efficiency. The model suggests that the postdialysis rebound in the blood urea concentration is eliminated by increasing flow to the low-flow compartment from 1.1 L/min to 7.1 L/min and sustaining this for at least 30 min of a 150-min dialysis session, independent of the dialyzer clearance. Additional exercise will not increase the dialysis dose. Experimental studies are required to confirm the analysis. PMID:9440097

Smye, S W; Lindley, E J; Will, E J

1998-01-01

392

Nitrogen leaching from Douglas-fir forests after urea fertilization.  

PubMed

Leaching of nitrogen (N) after forest fertilization has the potential to pollute ground and surface water. The purpose of this study was to quantify N leaching through the primary rooting zone of N-limited Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] forests the year after fertilization (224 kg N ha(-1) as urea) and to calculate changes in the N pools of the overstory trees, understory vegetation, and soil. At six sites on production forests in the Hood Canal watershed, Washington, tension lysimeters and estimates of the soil water flux were used to quantify the mobilization and leaching of NO(3)-N, NH(4)-N, and dissolved organic nitrogen below the observed rooting depth. Soil and vegetation samples were collected before fertilization and 1 and 6 mo after fertilization. In the year after fertilization, the total leaching beyond the primary rooting zone in excess of control plots was 4.2 kg N ha(-1) (p = 0.03), which was equal to 2% of the total N applied. The peak NO(3)-N concentration that leached beyond the rooting zone of fertilized plots was 0.2 mg NO(3)-N L(-1). Six months after fertilization, 26% of the applied N was accounted for in the overstory, and 27% was accounted for in the O+A horizon of the soil. The results of this study indicate that forest fertilization can lead to small N leaching fluxes out of the primary rooting zone during the first year after urea application. PMID:18689739

Flint, Cynthia M; Harrison, Rob B; Strahm, Brian D; Adams, A B

2008-01-01

393

Kinetic investigation of erucamide synthesis using fatty acid and urea.  

PubMed

Fatty acid amides like erucamide are mainly used for lubrication and as slip agent to decrease friction in polymer and plastic industry. Erucamide is normally synthesized by ammonolysis of triglycerides or fatty acids at 200 degrees C and at high pressure (345-690 kPa.). However using urea in place of ammonia the economic synthesis of erucamide is possible at atmospheric pressure at approx 190 degrees C. In present investigation, the kinetics of synthesis of erucamide by ammonolysis of erucic acid has been investigated. The optimum conditions for the synthesis of erucamide have also been determined. 1:4 molar ratio of erucic acid to urea, 190 degrees C temperature and catalyst [P2O5 with (NH4)2H PO4, {(1:1) w/w }] concentration 3% (by wt. of erucic acid) were the optimum condition for synthesis of erucamide from erucic acid and can obtain a maximum yield of 92% of pure erucamide. Some other catalysts as titanium-iso -propoxide, phosphorus pent oxide were also tried but these catalysts were not economical. PMID:18685229

Awasthi, Neeraj Praphulla; Upadhayay, Santosh K; Singh, R P

2008-01-01

394

Lipophilic Microconstituents of Milk  

Microsoft Academic Search

Milk has long been recognized as a source of macro- and micronutrients, immunological components, and biologically active\\u000a substances, which not only allow growth but also promote health in mammalian newborns. Many milk lipids, lipid-soluble substances,\\u000a and their digested products are bioactive, including vitamins and vitamin-like substances. Vitamins A, E, D, and K and carotenoids\\u000a are known as highly lipophilic food

Antonella Baldi; Luciano Pinotti

395

The endogenous GABA bioactivity of camel, bovine, goat and human milks.  

PubMed

GABA orally administered has several beneficial effects on health, including the regulation of hyperglycaemic states in humans. Those effects are similar to the effects reported for camel milk (CMk); however, it is not known whether compounds with GABAergic activity are present in milk from camels or other species. We determined CMk free-GABA concentration by LS/MS and its bioactivity on human GABA receptors. We found that camel and goat milks have significantly more bioavailable GABA than cow and human milks and are able to activate GABA? receptors. The relationship between GABA and taurine concentrations suggests that whole camel milk may be more efficient to activate GABA?1 receptors than goat milk. Because GABA? receptors are normally found in enteroendocrine cells in the lumen of the digestive tract, these results suggest that GABA in camel and goat milk may participate in GABA-modulated functions of enteroendocrine cells in the GI lumen. PMID:24128504

Limon, Agenor; Gallegos-Perez, Jose-Luis; Reyes-Ruiz, Jorge M; Aljohi, Mohammad A; Alshanqeeti, Ali S; Miledi, Ricardo

2014-02-15

396

Cheese quality from milk of grazing or indoor fed Zebu cows and Alpine crossbred goats  

Microsoft Academic Search

Sixty Alpine crossbred goats were pastured on 14ha of shrub land and 14 Zebu cattle on 16ha of a tropical Legume forest with grasses, both groups supplemented with a slow-intake urea mixture (SIUS). Milk production was sustained by the SIUS supplement, when forage growth was reduced, thus avoiding over-grazing of the rangeland, and production of cheese by the farmer was

M. A. Galina; F. Osnaya; H. M. Cuchillo; G. F. W. Haenlein

2007-01-01

397

Estimation of genetic parameters and detection of quantitative trait loci for metabolites in Danish Holstein milk.  

PubMed

Small components and metabolites in milk are significant for the utilization of milk, not only in dairy food production but also as disease predictors in dairy cattle. This study focused on estimation of genetic parameters and detection of quantitative trait loci for metabolites in bovine milk. For this purpose, milk samples were collected in mid lactation from 371 Danish Holstein cows in first to third parity. A total of 31 metabolites were detected and identified in bovine milk by using (1)H nuclear magnetic resonance (NMR) spectroscopy. Cows were genotyped using a bovine high-density single nucleotide polymorphism (SNP) chip. Based on the SNP data, a genomic relationship matrix was calculated and used as a random factor in a model together with 2 fixed factors (herd and lactation stage) to estimate the heritability and breeding value for individual metabolites in the milk. Heritability was in the range of 0 for lactic acid to >0.8 for orotic acid and ?-hydroxybutyrate. A single SNP association analysis revealed 7 genome-wide significant quantitative trait loci [malonate: Bos taurus autosome (BTA)2 and BTA7; galactose-1-phosphate: BTA2; cis-aconitate: BTA11; urea: BTA12; carnitine: BTA25; and glycerophosphocholine: BTA25]. These results demonstrate that selection for metabolites in bovine milk may be possible. PMID:23497994

Buitenhuis, A J; Sundekilde, U K; Poulsen, N A; Bertram, H C; Larsen, L B; Sørensen, P

2013-05-01

398

Neurological implications of urea cycle disorders  

PubMed Central

Summary The urea cycle disorders constitute a group of rare congenital disorders caused by a deficiency of the enzymes or transport proteins required to remove ammonia from the body. Via a series of biochemical steps, nitrogen, the waste product of protein metabolism, is removed from the blood and converted into urea. A consequence of these disorders is hyperammonaemia, resulting in central nervous system dysfunction with mental status changes, brain oedema, seizures, coma, and potentially death. Both acute and chronic hyperammonaemia result in alterations of neurotransmitter systems. In acute hyperammonaemia, activation of the NMDA receptor leads to excitotoxic cell death, changes in energy metabolism and alterations in protein expression of the astrocyte that affect volume regulation and contribute to oedema. Neuropathological evaluation demonstrates alterations in the astrocyte morphology. Imaging studies, in particular 1H MRS, can reveal markers of impaired metabolism such as elevations of glutamine and reduction of myoinositol. In contrast, chronic hyperammonaemia leads to adaptive responses in the NMDA receptor and impairments in the glutamate–nitric oxide–cGMP pathway, leading to alterations in cognition and learning. Therapy of acute hyperammonaemia has relied on ammonia-lowering agents but in recent years there has been considerable interest in neuroprotective strategies. Recent studies have suggested restoration of learning abilities by pharmacological manipulation of brain cGMP with phosphodiesterase inhibitors. Thus, both strategies are intriguing areas for potential investigation in human urea cycle disorders. PMID:18038189

Summar, M.; Leonard, J. V.

2013-01-01

399

A longitudinal study of urea cycle disorders.  

PubMed

The Urea Cycle Disorders Consortium (UCDC) is a member of the NIH funded Rare Diseases Clinical Research Network and is performing a longitudinal study of 8 urea cycle disorders (UCDs) with initial enrollment beginning in 2006. The consortium consists of 14 sites in the U.S., Canada and Europe. This report summarizes data mining studies of 614 patients with UCDs enrolled in the UCDC's longitudinal study protocol. The most common disorder is ornithine transcarbamylase deficiency, accounting for more than half of the participants. We calculated the overall prevalence of urea cycle disorders to be 1/35,000, with 2/3rds presenting initial symptoms after the newborn period. We found the mortality rate to be 24% in neonatal onset cases and 11% in late onset cases. The most common precipitant of clinical hyperammonemic episodes in the post-neonatal period was intercurrent infections. Elevations in both blood ammonia and glutamine appeared to be biomarkers for neurocognitive outcome. In terms of chronic treatment, low protein diet appeared to result in normal weight but decreased linear growth while N-scavenger therapy with phenylbutyrate resulted in low levels of branched chain amino acids. Finally, we found an unexpectedly high risk for hepatic dysfunction in patients with ornithine transcarbamylase deficiency. This natural history study illustrates how a collaborative study of a rare genetic disorder can result in an improved understanding of morbidity and disease outcome. PMID:25135652

Batshaw, Mark L; Tuchman, Mendel; Summar, Marshall; Seminara, Jennifer

2014-01-01

400

Colicin E1 forms a dimer after urea-induced unfolding.  

PubMed Central

Unfolding of the soluble colicin E1 channel peptide was examined with the use of urea as a denaturant; it was shown that it unfolds to an intermediate state in 8.5 M urea, equivalent to a dimeric species previously observed in 4 M guanidinium chloride. Single tryptophan residues, substituted into the peptide at various positions by site-directed mutagenesis, were employed as fluorescent probes of local unfolding. Unfolding profiles for specific sites within the peptide were obtained by quantifying the shifts in the fluorescence emission maxima of single tryptophan residues on unfolding and plotting them against urea concentration. Unfolding reported by tryptophan residues in the C-terminal region was not characteristic of complete peptide denaturation, as evidenced by the relatively blue-shifted values of the fluorescence emission maxima. Unfolding was also monitored by using CD spectroscopy and the fluorescent probe 2-(p-toluidinyl)-naphthalene 6-sulphonic acid; the results indicated that unfolding of helices is concomitant with the exposure of protein non-polar surface. Unfolding profiles were evaluated by non-linear least-squares curve fitting and calculation of the unfolding transition midpoint. The unfolding profiles of residues located in the N-terminal region of the peptide had lower transition midpoints than residues in the C-terminal portion. The results of unfolding analysis demonstrated that urea unfolds the peptide only partly to an intermediate state, because the C-terminal portion of the channel peptide retained significant structure in 8.5 M urea. Characterization of the peptide's global unfolding by size-exclusion HPLC revealed that the partly denatured structure that persists in 8.5 M urea is a dimer of two channel peptides, tightly associated by hydrophobic interactions. The presence of the dimerized species was confirmed by SDS/PAGE and intermolecular fluorescence resonance energy transfer. PMID:10359646

Steer, B A; DiNardo, A A; Merrill, A R

1999-01-01