Breed variations in the shape of the lactation curve of cattle and their implications for efficiency

1980 ◽  
Vol 31 (2) ◽  
pp. 133-141 ◽  
Author(s):  
P. D. P. Wood

ABSTRACTMean daily milk yield, fat percentage and protein percentage were recorded monthly, from August 1978 to July 1979. for 579 303 British Friesian, 6 608 Shorthorn, 27 374 Ayrshire, 19 529 Jersey, and 19 760 Guernsey cattle and classified by breed, parity and stage of lactation. Parameters of the function y(n) = anb ecn were estimated for each breed/parity group for yield, fat percentage and yield, protein percentage and yield, and energy (MJ) output as milk (b and c describe the shape of the curve, a is a scalar, n the week of lactation and e the base of natural logarithms). In the mature cows of each breed (parity 4 or more), the shape constants (b, c) for milk, fat and protein production in kg respectively were:Generally, cows of all five breeds which calved in the winter produced about 4% more milk, fat and protein than average, and those that calved in the summer produced about 4% less. After allowing for that, and removing the effect of the calving pattern, a seasonal variation in production occurred to produce a peak in June 1979 nearly 12% above average for liquid milk, in July 1979 about 4% for fat and in June 1979 about 12% for protein production (not percentage). Trough month was January 1979 for all three characters: —8%; —4% and — 9% respectively.A consideration of the theory of metabolizable energy suggested that the peak of energy output which occurred about week 4 of lactation in all breeds and parities, expressed as a fraction of the live weight of the animal, had a critical bearing on the need to mobilize body reserves.

1976 ◽  
Vol 22 (1) ◽  
pp. 35-40 ◽  
Author(s):  
P. D. P. Wood

SummaryThe lactation curves of whole milk production and of compositional quality measures may be represented by one of a family of curveswhere the coefficients a, b and c define the curve of production of a character y at week n.An analysis of protein results from over 600 000 cows, and of fat results from nearly 3000 cows gave shape coefficients (b, c) for fat percentage (-0·1316, 0·0154) and for protein percentage (-0·1223, 0·0109) showing that the lowest percentage of each occurred during weeks 8 and 11 of lactation respectively.Seasonal variations were calculated to show an expected deficiency of 0·93% fat in the spring and 0·75% protein in winter, which could be attributed to environmental influences associated with varying feeding standards.


1980 ◽  
Vol 31 (2) ◽  
pp. 143-151 ◽  
Author(s):  
P. D. P. Wood ◽  
J. O. L. King ◽  
P. G. Youdan

ABSTRACTLive weight, milk yield, fat, protein and lactose percentage of 236 cows and heifers of four breeds of dairy cattle were recorded at 2-week intervals, starting within a week after calving, during the winter and spring of 1972/73. Lactation curves of the form X(n) = Xnb ecn were fitted to each animal's records, where X, b, c are constants, e the base of natural logarithms and X(n) the value of the character at the nth 2-week interval. Correlations between the curves, and between deviations from the curves, showed that the production of milk, fat, protein and lactose was negatively correlated with live-weight change in the long term, but that deviations from the curves were not correlated. There were significant positive correlations between milk yield and size, and between potential compositional quality and size (the values of × in the model). Of the four breeds studied, Friesian, Ayrshire, Guernsey and Jersey, adult Friesian cows required less dietary energy per kg of total solids produced than any other group, according to the principles of the metabolizable energy system of calculating energy requirements. During the period of negative energy balance, an average 10% to 15% of energy output in the form of milk was derived from the mobilization of body reserves.


1969 ◽  
Vol 87 (3-4) ◽  
pp. 137-147
Author(s):  
Paul F. Randel ◽  
Jaime R. Moyá

Eighteen Holstein cows of approximately 550 kg mean live weight (LW), and 57 ± 24 days in milk at the start, were divided into six groups of three each for use in a single-reversal design, with two 5-wk experimental periods, to compare two treatments: T1, including a liquid feed (85% SynerMax5:15% cane molasses) offered in lick-wheel tanks to three groups between 7:00 a.m. and 2:00 p.m. (1.7-kg daily intake), plus a concentrate of solid ingredients (theoretically 1.8 Meal NEL/kg, 16% crude protein) fed individually according to milk yield, a small offering of grass hay (<3 kg consumed daily), and rotational grazing at night in four paddocks on mixed tropical grasses; T2, as in T1 but without liquid feed, rather including a larger concentrate allowance (10.5- vs. 11.6-kg intake). Mean results obtained with TI and T2, respectively: daily milk yield, 22.45 vs. 22.55 kg; milk fat percentage, 3.03 vs. 2.94; milk protein percentage, 2.68 vs. 2.76 (P < 0.01). Intakes of dry matter (DM) from high-energy supplements (solid concentrate plus liquid feed) were 10.2 vs. 10.3 kg, respectively. Daily DM intake from grazed forage by cows of both treatments in common pastures was estimated by a disk-drop method as 9.31 ± 2.68 kg. It is concluded that the liquid feed, when constituting 4 or 5% of total dietary DM, had a feeding value equal to that of the solid concentrate on a DM basis, but no synergistic effect was substantiated. 


Author(s):  
A. Zheltikov ◽  
N. Kostomakhin ◽  
D. Adushinov ◽  
O. Zaiko ◽  
V. Dementev ◽  
...  

The characteristic of milk productivity of cows of Holstein and Simmental breeds in LLC “Sibirskaya Niva” in the Maslyaninsky district in the Novosibirsk region has been given. It has been revealed that under the natural and climatic environments of the Western Siberia, when creating favorable conditions for feeding and housing for cows of Holstein and Simmental breeds have sufficiently high milk productivity. It has been found that Holstein first-calf heifers surpassed their Simmental herdmates by 959 kg in milk yield for the first 305 days of lactation under the same conditions of housing and feeding, by 3,1 kg in daily milk yield, by 38,2 kg in milk fat yield, and by 28,3 kg in milk protein yield (P < 0,001). There were no statistically significant differences between animals of Holstein and Simmental breeds in terms of fat and protein content in milk, which amounted to 3,94 and 2,96 % in Holstein breed and 3,97 and 2,98 % in Simmental breed, respectively. Both breeds have shown high milk productivity during the first 3 lactations. Thus, the milk yield of Holstein cows for the first 3 lactation was 6475–9290 kg, Simmental cows it was 5516–7680 kg, fat content was 3,93–3,99 and 3,96–3,97 %, respectively. The protein content in the milk of cows of both breeds did not exceed 3,0 %. High variability has been found in milk yield, yield of milk fat and protein, the coefficient of milk content and duration of lactation, the lowest in the content of protein and fat in milk and live weight. The correlation coefficients between the fat and protein content in milk were generally positive, but did not exceed 0,28. Therefore, breeding in the herd of cows in LLC “Sibirskaya Niva” have to be conducted not only by fat content, but also by protein content in milk.


1990 ◽  
Vol 70 (2) ◽  
pp. 731-734 ◽  
Author(s):  
A. S. ATWAL ◽  
J. D. ERFLE

Large day-to-day variations in milk fat, particularly for the morning milkings, were observed in 36 Holstein cows. Changes in percent fat were gradual and produced wavelike patterns in a number of instances. Supplemental feeding of long hay had no effect on acetate/propionate ratio in rumen fluid, daily milk yield or weighted milk fat percentage. Key words: Dairy cows, milk, fat depression, hay


1995 ◽  
Author(s):  
Joel Weller ◽  
Harris Lewin ◽  
Micha Ron ◽  
George Wiggans

Forty-seven poly-TG microsatellites were developed at the U of IL, and 11 genetic markers were developed at ARO, nine of which were poly-AGC microsatellites. Markers were typed on the reference families of CSIRO, Australia; GRANADA, Texas; and IRRF, Illinois, for chromosome assignment and linkage mapping. Nine North American al organizations contributed semen to the Dairy Bull DNA Repository (DBDR), which currently has 65,743 units from 3366 bulls. Semen was obtained for 31 out of 35 grandsires. Semen of 28 and 23 sons of two Israeli bulls was also collected. Eighteen grandsires were genotyped for 75 microsatellites. One thousand, three hundred and sixty-two sons with evaluation from 17 families were genotyped for 24 markers. Eleven thousand, six hundred and twenty sons genotypes were determined, of which 8,802 were informative. The genotype data was matched to the bulls' daughter yield deviations (DYD) for seven traits; milk, fat, and protein production; fat and protein percent; somatic cell concentration (SCS); and productive herd life. Seven loci had significant effects at p<0.05, but only two loci, TGLA263 and MGTG7, had significant effects at p<0.01, and the effect of TGLA263 on fat percentage was significant at p<0.0001. There was at least one significant effect for each of the seven traits analyzed.


2019 ◽  
Vol 99 (3) ◽  
pp. 521-531
Author(s):  
M. Duplessis ◽  
R. Lacroix ◽  
L. Fadul-Pacheco ◽  
D.M. Lefebvre ◽  
D. Pellerin

1999 ◽  
Vol 132 (4) ◽  
pp. 483-490 ◽  
Author(s):  
C. P. FERRIS ◽  
F. J. GORDON ◽  
D. C. PATTERSON ◽  
M. G. PORTER ◽  
T. YAN

Sixty Holstein/Friesian dairy cows, 28 of high genetic merit and 32 of medium genetic merit, were used in a continuous design, 2 (cow genotypes)×4 (concentrate proportion in diet) factorial experiment. High and medium merit animals had Predicted Transmitting Abilities for milk fat plus protein yield, calculated using 1995 as the base year (PTA95 fat plus protein), of 43·3 kg and 1·0 kg respectively. Concentrate proportions in the diet were 0·37, 0·48, 0·59 and 0·70 of total dry matter (DM), with the remainder of the diet being grass silage. During this milk production trial, 24 of these animals, 12 from each genetic merit, representing three animals from each concentrate treatment, were subject to ration digestibility, and nitrogen and energy utilization studies. In addition, the efficiency of energy utilization during the milk production trial was calculated.There were no genotype×concentrate level interactions for any of the variables measured (P>0·05). Neither genetic merit nor concentrate proportion in the diet influenced the digestibility of either the DM or energy components of the ration (P>0·05). When expressed as a proportion of nitrogen intake, medium merit cows exhibited a higher urinary nitrogen output and a lower milk nitrogen output than the high merit cows. Methane energy output, when expressed as a proportion of gross energy intake, was higher for the medium than high merit cows (P<0·05), while urinary energy output tended to decrease with increasing proportion of concentrate in the diet (P<0·05). In the calorimetric studies, neither heat energy production, milk energy output and energy retained, when expressed as a proportion of metabolizable energy intake, nor the efficiency of lactation (kl), were affected by either cow genotype or concentrate proportion in the diet (P>0·05). However when kl was calculated using the production data from the milk production trial the high merit cows were found to have significantly higher kl values than the medium merit cows (0·64 v. 0·59, P<0·05) while k l tended to fall with increasing proportion of concentrate in the ration (P<0·05). However in view of the many assumptions which were used in these latter calculations, a cautious interpretation is required.


1988 ◽  
Vol 110 (2) ◽  
pp. 261-270 ◽  
Author(s):  
J. D. Sutton ◽  
W. H. Broster ◽  
E. Schuller ◽  
D. J. Napper ◽  
Valerie J. Broster ◽  
...  

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.


1988 ◽  
Vol 47 (2) ◽  
pp. 185-190 ◽  
Author(s):  
F. J. Manson ◽  
J. D. Leaver

ABSTRACTAn experiment with two groups of 24 cows during weeks 3 to 22 of lactation examined the influence of 7 (L) or 11 (H) kg concentrates per day on the prevalence of lameness. Grass silage was offeredad libitum. The cows were scored on a 1 to 5 scale for their locomotion on a weekly basis (1 = normal locomotion; 5 = severely lame). Cows scoring 3 or more were considered to be clinically lame. This allowed the prevalence of lameness, its severity and duration to be measured and statistically analysed. There were significantly more observations of lameness in the H cows than the L cows (0·077 and 0·021 observations per cow week) and the severity and duration of lameness incidents were significantly greater. The major causes of lameness were solar problems in the hind feet. The prevalence declined in both treatments as lactation progressed. The predisposing causes of the higher incidence in treatment H could have been the higher concentrate: forage ratio, the greater daily metabolizable energy intake or the greater daily crude protein intake. For treatments L and H, mean milk yields were 20·5, 23·7 kg/day; milk fat 41·7, 39·0 g/kg; milk protein 31·4, 32·0 g/kg; live-weight change -0·12, +0·11 kg/day; and condition score 2·04, 2·18.


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