scholarly journals Responses to postruminal infusions of glucose and casein in lactating goats

1977 ◽  
Vol 37 (3) ◽  
pp. 395-402 ◽  
Author(s):  
S. S. E. Ranawana ◽  
R. C. Kellaway
Keyword(s):  
Amino Acids ◽  
Milk Production ◽  
Milk Fat ◽  
Live Weight ◽  
Milk Composition ◽  
Glucose Infusion ◽  
Kinetic Measurements ◽  
Lactating Goats ◽  
Arterial Plasma ◽  
Basal Ration

1. A study was made in goats of the response in terms of milk production, nitrogen utilization, plasma amino acids and glucose kinetics to postruminal infusions of glucose and casein. Goats in mid-lactation, housed in metabolism cages, were fed on 2 kg basal ration (containing 112 g crude protein (N × 6.25)/kg)/d alone (control) and with daily infusions into the abomasum of 45 g casein or 45 g glucose.2. Milk production increased with casein infusion (P < 0.01), but not with glucose infusion, being 1.59, 1.86 and 1.62 kg/d with the control, casein and glucose infusions respectively. Milk composition was unaffected except for milk fat, which was decreased by the glucose infusion.3. The goats were in positive N balance on the basal ration. Milk N output increased with casein infusion, by an amount equivalent to 27% of the infused N.4. The concentration of dispensable amino acids in arterial plasma was decreased with casein infusion and increased with glucose infusion.5. Glucose kinetic measurements with control, casein and glucose infusions indicated that pool sizes were 247, 279 and 302 mg/kg live weight0.75, and irreversible losses were 5.5, 6.7 and 7.0 mg/kg live weight0.75 per min respectively. The differences between the results obtained from the glucose and casein infusions were not significant (P < 0.05).6. The results of the experiment indicate that the increased milk production obtained when casein was infused was not due to enhanced gluconeogenesis.

scholarly journals Responses to postruminal infusions of graded levels of casein in lactating goats

1977 ◽  
Vol 37 (1) ◽  
pp. 67-79 ◽  
Author(s):  
S. S. E. Ranawana ◽  
R. C. Kellaway
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Milk Production ◽  
Milk Fat ◽  
Acid Uptake ◽  
Plasma Urea ◽  
Arterial Blood ◽  
Lactating Goats ◽  
Indispensable Amino Acids ◽  
Basal Ration

1. A study was made in goats of the response in terms of milk production, nitrogen utilization, plasma amino acids and amino acid uptake by the mammary gland, to postruminal infusion of casein. Goats in early lactation, housed in metabolism cages, were fed on 2.5 kg basal ration/d (containing 111 g crude protein (N × 6.25)/kg) and were given, by infusion into the abomasum, 0, 15, 30 or 45 g casein/d.2. Milk production increased from 2.41 kg/d on the basal ration to 2.52, 2.80 and 2.94 kg/d in response to infusions of 15, 30 and 45 g casein/d respectively. Milk composition was unaffected except for milk fat, which was slightly decreased during infusions of the higher levels of casein.3. The goats were found to be in positive N balance on the basal ration. Milk N output increased with casein infusion; the increase was equivalent to a maximum of 49% of the infused N.4. The concentration of glucose in arterial blood plasma was decreased at the highest level of casein infusion, but that of plasma urea N was unaffected by treatments.5. Casein infusions increased the concentrations of total indispensable amino acids and the ratio, indispensable: dispensable amino acids in arterial plasma. Arterial concentrations and mammary extractions of most indispensable amino acids were increased, but only a few increases were statistically significant (P< 0.05).6. Comparison of individual indispensable amino acids absorbed from the intestine with output in milk indicated that methionine was probably the first limiting amino acid.7. The results of the experiment were compared to those of similar experiments with cows that have been reported by other workers. The possible ways in which the infused casein may have caused the responses were discussed. However, no firm conclusions regarding the mechanism involved could be drawn from the results of the present study.

Protein studies on maize silage as a basal ration for dairy cows

1981 ◽  
Vol 96 (2) ◽  
pp. 283-290 ◽  
Author(s):  
R. H. Phipps ◽  
R. F. Weller ◽  
T. Smith ◽  
Rosemary J. Fulford
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Nitrogen Loss ◽  
Live Weight ◽  
Milk Composition ◽  
Maize Silage ◽  
Acid Detergent Fibre ◽  
Soya Bean Meal ◽  
Curvilinear Relationships ◽  
Basal Ration

SUMMARYIn Expt 1 40 lactating British Friesians, 20 cows and 20 heifers, were used to study the effect of crude protein (CP) content of the whole ration on milk yield, milk composition and live-weight change when maize silage was fed as the basal ration. There were four treatments with five cows and five heifers on each. During lactation weeks 4–12 the cows on treatments 1, 2, 3 and 4 all received 7 kg maize silage dry matter (D.m.) plus 8 kg D.m./day of a concentrate containing either 14, 18, 22 or 24% CP, respectively; heifers received 1 kg/day less of both silage and concentrate. This produced whole-ration CP contents of 11·7, 13·9, 16.·0 and 17·1%. In the subsequent lactation weeks 13–20 silage feeding was increased to 9 kg D.m./cow/day and concentrate feeding decreased to 5 kg D.m./cow/day. Heifers again received 1 kg/day less of both silage and concentrate. This decreased whole-ration CP contents to 10·5, 11·7, 12·9 and 13·4%.During lactation weeks 4–12 and 13–20, with the exception of milk fat content in weeks 13–20, there were significant linear effects of whole-ration CP content on milk yield, milk fat, protein, lactose and total solids. There were no significant curvilinear relationships. Thus, despite the fact that the highest numerical values were generally recorded for the animals on treatment 3, the results indicate that a whole-ration CP content of at least 17·1 and 13·4% are required in early and mid-lactation respectively.In Expt 2 the loss of D.m., acid-detergent fibre and nitrogen from maize silage suspended in nylon bags in the rumen was measured. Compared with feeding either a low or high protein supplement, losses were greater for silage fed alone. If it is accepted that nitrogen loss can be approximated to protein degradability, then the value for maize silage was between 0·6 and 0·7. Using the same technique in Expt 3, comparable nitrogen losses for fish meal, decorticated groundnut meal and soya-bean meal were 0·3, 0·9 and 0·9, respectively, after 24 h incubation.

The Effect of Concentrate Type and Supplementary Lactic Acid or Soya-Oil on Milk Production in Dairy Cows Offered Restricted or Extensively Fermented Grass Silages

1994 ◽  
Vol 1994 ◽  
pp. 38-38
Author(s):  
J G Doherty ◽  
C S Mayne
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Fat ◽  
Milk Composition ◽  
Fresh Weight ◽  
Single Strain ◽  
High Fibre ◽  
Soyabean Meal ◽  
High Starch ◽  
Aliphatic Carboxylic Acids

Several studies have shown increased silage dry-matter intake (SDMI) and improved milk fat concentrations in dairy cows offered restricted fermented grass silages compared to more extensively fermented silages. A recent study suggested that differences in silage intakeper serather than an alteration in rumen fermentation may be responsible for the changes in milk composition observed in the previous studies (Doherty and Mayne, 1993). The aim of the present study was to examine the effect of changes in concentrate composition on milk production parameters in dairy cows offered grass silages of contrasting fermentation type.Two direct cut grass silages were prepared using either an inoculant, containing a single strain ofLactobacillus plantarum, (Ecosyl, 3 1/t fresh weight, Zeneca Products Ltd) or a mixture of aliphatic carboxylic acids (Maxgrass, 6 1/t fresh weight, BP Chemicals Ltd). Two concentrates (high starch or high fibre) were formulated containing either: barley, 300; wheat, 355; and soyabean-meal, 270 g/kg (high starch) or unmolassed sugar-beet pulp, 555; citrus pulp, 100; and soyabean-meal, 270 g/kg (high fibre).

scholarly journals Characteristics of the productive-economic indicators of cows of Yaroslavl breed of different genotypes

2020 ◽  
pp. 43-52
Author(s):  
N. Kosyachenko ◽  
Marina Abramova ◽  
M. Lapina
Keyword(s):  
Protein Content ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Live Weight ◽  
Practical Significance ◽  
Holstein Breed ◽  
Blood Fraction ◽  
The Impact ◽  
The Relationship

Abstract. Aim. The study of the influence of crossbriding on the growth and development of heifers and subsequent productive and reproductive qualities of cows on the first lactation. Methods. Using statistical methods, correlation analysis and ANOVA for evaluated genetic indicators of economic-valuable traits of dairy cattle. In particular was studied live weight of heifers from birth to 18 months, first insemination age and first fecundation age, live weight at fecundation, frequency of insemination, first calving age, days open, live weight at first lactation, milk yield for 305 days (kg), fat (%, kg) and protein (%, kg) in milk. Results. Relationship between productive indicators and the genotype of the animal is established. When assessing the strength of the influence of the factor «blood on the Holstein breed» it was found that the greatest impact can be traced at the age of 6 and 18 months, and is respectively 12.7 % and 17.1 %.The reproductive qualities of the first-calf cows decreased with the increase percent of blood in the Holstein breed. Evaluation of the impact of crossbreeding on milk production at first lactation has revealed significant strong influence on milk yield for 305 days of first lactation, and related signs the amount of milk fat and protein. According to qualitative indicators, the low influence of the Holstein blood fraction was found, while to a greater extent on the fat content than on the protein content in milk. Evaluation of phenotypic and genotypic correlations of milk yield and quality components of milk revealed average negative phenotypic and low negative genotypic correlation in all groups. The exception was in heifers of Yaroslavl breed with percent of Holstein blood less than 50 %, in which the relationship of yield x protein was positive. The relationship between milk yield and fat and protein content in milk has the opposite moderate character and strength. Practical significance. Studies was established that breeding of animals of Holstein and Yaroslavl breeds in one herd allows to receive an optimum ratio of milk production with optimal percentage fat and protein. For this herd among animals of the improved genotypes of the Yaroslavl breed, the use of genotypes with a percent of blood in the Holstein breed from 75.1 % to 87.6 % is optimal, which should be taken into account when selecting bulls to the breeding program.

Value for milk production of artificially dried forages as cobs and pellets

1972 ◽  
Vol 14 (1) ◽  
pp. 69-75 ◽  
Author(s):  
J. A. Milne ◽  
E. F. Thomson ◽  
R. C. Campling
Keyword(s):  
Milk Production ◽  
Milk Yield ◽  
Live Weight ◽  
Fat Content ◽  
Significant Positive Effect ◽  
Significant Difference ◽  
Four Levels ◽  
Milk Solids ◽  
Positive Effect ◽  
Basal Ration

SUMMARYTwo experiments were conducted to compare the milk-producing value of dried forages in the form of cobs and pellets as replacements for a standard dairy concentrate. Four levels (0·33, 0·44, 0·55 and 0·66 kg/kg milk) of dried forage or standard dairy concentrate were offered in addition to a basal ration of 6 kg hay and 2 kg standard dairy concentrate. In both experiments the rate of eating by the cows of cobs was significantly slower (P<0·05) than that of pellets. No significant difference was found between the cobs and pellets in either experiment in their value for milk production. In Experiment 2 the standard dairy concentrate had a non-significantly higher (P>0·05) milk-producing value than the dried lucerne. Level of feeding had a significant positive effect on the milk yield (P< 0·001) of cows offered the dried grass and lucerne and on the milk solids- not-fat content (P<0·05) and live weight (P<0·01) of cows offered the dried grass, lucerne and standard dairy concentrate.

scholarly journals Effect of Milk Intake, Its Composition, and Fatty Acid Profile Distribution on Live Weight of Suckling Wallachian Lambs until Their Weaning

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 718 ◽  
Author(s):  
Martin Ptáček ◽  
Michal Milerski ◽  
Luděk Stádník ◽  
Jaromír Ducháček ◽  
Vladimír Tančin ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Milk Production ◽  
Milk Fat ◽  
Vaccenic Acid ◽  
Linear Regression Analysis ◽  
Live Weight ◽  
Profile Distribution ◽  
Production Increase ◽  
Daily Milk Production ◽  
Trans Vaccenic Acid

This study determined effects of milk production, milk components, or fatty acids (FA) profile on live weight of suckling lambs till their weaning. Live weight (LW, kg) of 42 purebred Wallachian lambs (from 33 ewes) was recorded during four control days with approximately 30-day intervals during rearing. At the same time, their mothers were examined for milk production (kg), milk fat (g), proteins (g), lactose (g), and fatty acids (%) contents. Results investigated using linear regression analysis showed 5.93 kg (p < 0.05) increase of lambs LW corresponded with 1 kg of ewe’s daily milk production increase during the observed period. Similarly, significant 0.13 kg or 0.11 kg increases of lambs live weight corresponded with 1 g increase of milk protein or milk lactose at this time. Milk with higher prevalence of trans-palmitoleic acid, trans-vaccenic acid, cis-vaccenic acid, linolelaidic acid, linoleic acid, or conjugated linolenic acid (CLA) significantly improved lambs LW. Moreover, significantly positive Pearson partial correlation between LW and trans-vaccenic acid (r = 0.305) or CLA (r = 0.347) indicated on genetic correlation between these traits. Therefore, milk (natural or artificially supplied) with higher distribution of these specified FAs could improve lambs’ LW.

Lactation response of cows to different levels of ruminally inert conjugated linoleic acids under commercial conditions

2005 ◽  
Vol 85 (2) ◽  
pp. 231-242 ◽  
Author(s):  
Rachel Gervais ◽  
Richard Spratt ◽  
Martin Léonard ◽  
P. Yvan Chouinard
Keyword(s):  
Linoleic Acid ◽  
Dairy Cows ◽  
Conjugated Linoleic Acid ◽  
Milk Production ◽  
Milk Fat ◽  
Metabolic Profile ◽  
Milk Composition ◽  
Dietary Lipids ◽  
Calcium Salts ◽  
Lactating Cows

Dietary conjugated linoleic acid (CLA) supplements have been shown to reduce milk fat synthesis in dairy cows. A rumen-inert source of CLA is required for commercial feed applications. The conversion of dietary lipids to a calcium salt is considered as a method to counter the extensive hydrogenation of dietary lipids that occurs in the rumen. Our objective was to determine whether feeding calcium salts of CLA under commercial conditions would affect milk production, milk composition and blood metabolic profile. A total of 240 dairy cows from eight farms were blocked according to the calving date, and randomly assigned to four treatments providing CLA at 0, 8, 16 and 32 g d-1. Milk production was recorded and milk was sampled on day 0, 7, 14, 28 and 42 of the feeding period. Blood samples were taken on day 42 from early-lactating cows (< 157 d in milk) to determine the metabolic profile. Milk fat yield was decreased 11, 20 and 28%, and milk fat concentration was reduced 13, 22 and 28% (linear; P < 0.001) when cows received 8, 16 and 32 g d-1 of CLA, respectively. Milk yield, milk protein and blood metabolic parameters were not affected by experimental treatments. Calcium salts of CLA can be used as an effective tool to manage milk fat content on commercial dairy farms. Key words: Conjugated linoleic acid, milk fat, ruminally inert fat

The effect of different levels of nutrition at two stages of the lactation on milk production and live-weight change in Friesian cows and heifers

1981 ◽  
Vol 96 (3) ◽  
pp. 677-690 ◽  
Author(s):  
M. J. Strickland ◽  
W. H. Broster
Keyword(s):  
Milk Production ◽  
Milk Fat ◽  
Live Weight ◽  
Residual Effects ◽  
Early Lactation ◽  
Or Groups ◽  
Regular Increase ◽  
Experimental Treatments ◽  
Two Stages ◽  
Friesian Cows

SUMMARYOver the 4 years 1965–8, a total of 105 mature Friesian cows and 84 Friesian heifers were fed various levels of nutrition at two stages of the lactation to study the effect on milk production. The experiments were carried out over a whole lactation at four Experimental Husbandry Farms, Boxworth, Bridget's, Great House and Trawsgoed. There were three treatment levels in early lactation (weeks 3–10) comprising 5·9, 7·8 or 9·8 kg D.M./day of concentrates for mature cows and 1·6 kg D.M./day less at each level for the heifers. In mid-lactation (weeks 12–18) the two lower levels of concentrates were fed arranged factorially with early-lactation levels. A basal forage ration usually of hay was fed to provide 85% of the basal maintenance requirements. During the remainder of the lactation all animals received the same level of nutrition. In addition to the pre-determined feed treatments, one further group of animals in each block was fed according to the milk production in the preceding week.Overall an increase in level of nutrition in early lactation produced a regular increase in milk production from successive increments with adult cows but only for the first increment with heifers. Raising feed level in mid-lactation increased milk production for all animals. There were considerable residual effects from early-lactation feeding but these were less with mid-lactation feeding. These same effects were also noted with yields of solids-not-fat and to a less extent in milk fat production.The experimental results indicated not only the mean effects of treatments but more important the interaction with individual animals. Study of the response of individual animals indicated that the effects of level of feeding varied in proportion to the potential of the cow. The presentation of mean results can therefore be misleading. The potential of a cow was indicated by milk production in the immediate post-calving period. This period could be used both in experimental designs for selecting animals in the allocation to experimental treatments and also in the practical context for rationing individuals or groups of cattle.The absolute plane of nutrition related to the potential of the animal was the most important factor in determining the efficiency of utilization of feed for milk production.

Influence of plane of nutrition and diet composition on rumen fermentation and energy utilization by dairy cows

1988 ◽  
Vol 110 (2) ◽  
pp. 261-270 ◽  
Author(s):  
J. D. Sutton ◽  
W. H. Broster ◽  
E. Schuller ◽  
D. J. Napper ◽  
Valerie J. Broster ◽  
...  
Keyword(s):  
Milk Production ◽  
Milk Fat ◽  
Energy Production ◽  
Diet Composition ◽  
Live Weight ◽  
Dietary Factors ◽  
Metabolizable Energy ◽  
Energy Utilization ◽  
Early Lactation ◽  
Nutrition And Diet

SummaryMean digestible energy (DE) intakes of 147 cows of three parities receiving three levels of DE including one ad libitum (about 2·2, 2·6 and 3·3 multiples of maintenance (MM)) drawn from three mixed diets containing hay and 60, 75 or 90% compound were calculated.Rumen samples were taken from three-quarters of the cows at monthly intervals throughout the experiment. Molar proportions of volatile fatty acids (VFA) in the rumen were not affected by stage of lactation over the 36 weeks of the experiment. The proportion of acetic acid decreased and that of propionic acid increased with greater intakes and with higher proportions of compound in the diet. The proportion of n-butyric acid was little affected by level of intake but decreased with increasing proportions of compound. In young, non-lactating cattle given the same diets but at lower levels of intake, VFA proportions were unaffected by diet composition at intakes of about 0·7 MM but at intakes of about 1·3 MM the proportion of acetate decreased and that of propionate increased when the proportion of compound was increased from 75 to 90%.The efficiency of milk energy production in relation to DE or metabolizable energy (ME) above maintenance decreased with increasing level of intake but was little affected by the proportion of compound. Partition towards live weight increased with level of intake in early lactation but not in late lactation. It also increased with higher proportions of compound in mid and late lactation but not in early lactation.Estimates of the ME requirement for live-weight change (LWC) were in reasonable agreement with recently published standards in early lactation when live weight was decreasing, but later in lactation when live-weight gain was occurring, a much higher value was calculated which is difficult to reconcile with these standards.Rumen VFA proportions were related to dietary fibre concentration and level of intake additively. The relationship to VFA proportions was close for milk fat concentration, but less so for energy partition towards live weight and none was apparent for the efficiency of ME utilization for milk energy production. It is suggested that both the reduction in milk fat concentration and the increase in milk yield in response to reductions in the fibre content of diets may be independently related to the increase in the proportion of propionate in the rumen VFA.It is concluded that further progress in studies of the dietary factors affecting the efficiency of milk production will require measurements of nutrient uptake from the digestive tract and description of milk production and LWC in terms of their chemical composition rather than energy alone.

Effects of intramammary arterial infusion of essential amino acids in the lactating goat

1974 ◽  
Vol 41 (1) ◽  
pp. 101-109 ◽  
Author(s):  
J. L. Linzell ◽  
T. B. Mepham
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Milk Protein ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Acid Uptake ◽  
Lactating Goats ◽  
Arterial Concentration ◽  
Arterial Plasma ◽  
Amino Acid Concentrations

SummaryExperiments were performed on 3 lactating goats, in which mammary arterial plasma amino-acid concentrations were elevated by the infusion of a solution of essential amino-acids into the carotid artery supplying a transplanted mammary gland. In 2 experiments there were marked elevations in the arterial concentrations of most essential amino acids, but in one case only did this result in significantly increased uptake of amino acids by the gland, the arterio-venous difference being significantly correlated with arterial concentration for all except one amino acid. In the experiment in which increased amino-acid uptake was observed, infusion also resulted in a significantly increased milk yield and increased milk protein yield. The results are discussed in relation to data from other laboratories and lead to the suggestion that milk protein synthesis may be limited by the availability of either methionine or tryptophan.

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