Download or read book The Effect of Body Weight During the Rearing Period on Milk Production in Qu bec Dairy Cattle written by Diana Figueroa Delgado and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Canadian dairy industry is composed of around 11,000 farms and approximately 1.4 million head, of which approximately 30 percent are heifers (Canadian Dairy Information Centre, 2018). Heifers are of great importance because they represent the future of dairy farms, and, without them, the herds could not evolve and continue producing over time. Producers select replacement heifers that have the potential to become more profitable than the existing cows that will eventually be replaced. Therefore, they should be raised to reach an adequate size and body weight for breeding, so that they can reproduce successfully, and subsequently become productive. This process of rearing replacement heifers can cost as much as 20 percent of the total production expenses on dairy farms (Delgado et al., 2015). The rearing period of a heifer does not only impact the actual growth rate of the animal early on; some researchers have also discussed longer-lasting effects on the animals' performance as lactating dairy cows (Soberon et al., 2012; Macdonald et al., 2005; Krpálková et al., 2014). The objective of this research was to determine the effects of body weight during rearing on the future milk production of Quebec dairy cattle. This was performed by looking at three periods of growth in a heifer's pre-lactation life - birth to weaning; pre-pubertal; and post-pubertal - and analysing the effect of their respective body weight categories on future milk production. Data were provided by the Quebec Dairy Herd Improvement Agency (Valacta), and included body-weight measurements, breeding records, and information for first, second, and third and plus lactations of Holstein dairy cattle. The study covered the years 2000 to 2015, and analyzed production and economic variables such as milk, protein, and fat yield (lactation and 305-day), gross profit, milk value and feed cost. The analyzed data consisted of a total of 22,312, 16,352 and 7,494 animals for the first, second and the third and plus lactations, respectively. While there was a tendency for heavier body weights up until 90 days of life (birth to weaning period) to have higher yields than lighter weights, the body-weight category of 110 to 124kg (not the heaviest) was found to have a significant effect on future first lactation milk, protein and fat production. Furthermore, pre-pubertal body weight had a significant effect on the first, second, and third and plus lactations where higher weights produced significantly higher first and second milk and milk-component yields. The effect of body weight during the post-pubertal period was significant on the first and second lactation where animals that weighed e"10kg had higher milk, protein and fat yields. Some of the findings may have been influenced by the substantially lower number of observations in the third and later lactations, pointing to the industry's challenge of longer herd life. In addition, the lack of animals that had weight measurements (both a sufficient number, and a range throughout the complete rearing period) serves to encourage increased recording by producers and advisors, so that the data can be used for better lifetime analyses."--

Download or read book The Effect of Body Weight During the Rearing Period on Milk Production in Que bec Dairy Cattle written by Diana Figueroa Delgado and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Canadian dairy industry is composed of around 11,000 farms and approximately 1.4 million head, of which approximately 30 percent are heifers (Canadian Dairy Information Centre, 2018). Heifers are of great importance because they represent the future of dairy farms, and, without them, the herds could not evolve and continue producing over time. Producers select replacement heifers that have the potential to become more profitable than the existing cows that will eventually be replaced. Therefore, they should be raised to reach an adequate size and body weight for breeding, so that they can reproduce successfully, and subsequently become productive. This process of rearing replacement heifers can cost as much as 20 percent of the total production expenses on dairy farms (Delgado et al., 2015). The rearing period of a heifer does not only impact the actual growth rate of the animal early on; some researchers have also discussed longer-lasting effects on the animals' performance as lactating dairy cows (Soberon et al., 2012; Macdonald et al., 2005; Krpa̹lkova̹ et al., 2014). The objective of this research was to determine the effects of body weight during rearing on the future milk production of Quebec dairy cattle. This was performed by looking at three periods of growth in a heifer's pre-lactation life - birth to weaning; pre-pubertal; and post-pubertal - and analysing the effect of their respective body weight categories on future milk production. Data were provided by the Quebec Dairy Herd Improvement Agency (Valacta), and included body-weight measurements, breeding records, and information for first, second, and third and plus lactations of Holstein dairy cattle. The study covered the years 2000 to 2015, and analyzed production and economic variables such as milk, protein, and fat yield (lactation and 305-day), gross profit, milk value and feed cost. The analyzed data consisted of a total of 22,312, 16,352 and 7,494 animals for the first, second and the third and plus lactations, respectively.While there was a tendency for heavier body weights up until 90 days of life (birth to weaning period) to have higher yields than lighter weights, the body-weight category of 110 to 124kg (not the heaviest) was found to have a significant effect on future first lactation milk, protein and fat production. Furthermore, pre-pubertal body weight had a significant effect on the first, second, and third and plus lactations where higher weights produced significantly higher first and second milk and milk-component yields. The effect of body weight during the post-pubertal period was significant on the first and second lactation where animals that weighed 9́Æ410kg had higher milk, protein and fat yields.Some of the findings may have been influenced by the substantially lower number of observations in the third and later lactations, pointing to the industry's challenge of longer herd life. In addition, the lack of animals that had weight measurements (both a sufficient number, and a range throughout the complete rearing period) serves to encourage increased recording by producers and advisors, so that the data can be used for better lifetime analyses." --

Download or read book Effect of Length of Previous Dry Period Month of Freshening Age Body Weight and Length of Gestation on Milk and Fat Yields of Dairy Cattle written by Cecil Douglas Clawson and published by . This book was released on 1964 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Relations Between Weight at First Calving and Milk Production During the First Lactation written by Robert H. Miller and published by . This book was released on 1958 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dairy Herd Health written by Martin Green and published by CABI. This book was released on 2012 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dairy cow herd health is an important and universal topic in large animal veterinary practice and farming, covering both preventive medicine and health promotion. With the move towards large scale farming, the health of the herd is important as an economic unit and to promote the health of the individuals within it. This book will focus on diseases within herds, herd husbandry practices, youngstock management and environmental issues. Major diseases and conditions will be covered such as mastitis, lameness, nutrition, metabolic and common infectious diseases from a herd health perspective.

Download or read book Optimisation of Age and Body Weight at First Calving and First Service Period for Milk Production in Dairy Cattle written by Krishan Singh Dangi and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interrelationships Among Age Body Weight and Production Traits in Dairy Cattle written by David Arthur Harville and published by . This book was released on 1964 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Requirements Growth Patterns and Production of Dairy Cattle written by Jerry Max Rakes and published by . This book was released on 1976 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interrelationships Among Characteristics of Body Form and Milk Production in Dairy Cattle written by Glen Raymond Ufford and published by . This book was released on 1970 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluations of body form and measures of milk production were recorded for 188 Holstein lactations and 77 Jersey lactations in the Oregon State University Dairy Herds. Components of body form included general appearance, dairy character, body capacity, and mammary system and 34 sub-components of these four traits plus body weight and wither height. Subjective components of body form were scored by two judges at approximately 30 days post-partum independent of age and previous score. Measures of milk production included actual and mature equivalent yields of milk, fat, and SNF, and percentages of fat and SNF plus peak yield, persistency of milk yield, solids-corrected milk, and test-day yields of milk for the first six months of lactation. Age at parturition and estimated breeding value were also included in this study. Sub-components of body form were quite effective in explaining the variation in the four major components. General appearance, dairy character, body capacity, and mammary system had R2 values of .84, .94, .95, and .95, and .82, .95, .94, and .96, respectively for Holsteins and Jerseys. Correlations among the sub-components of dairy character and of body capacity were quite strong, ranging from .49 to .96 for both breeds. Correlations among the sub-components of general appearance were lowest and the most variable of the four major components ( -.08 to .91). Correlations among components of mammary system were intermediate. Path coefficients indicated that the sub-components with the most effect on overall score for general appearance were stature, feet and legs, and rump or its components. Sub-components of dairy character had about equal effects on overall score for dairy character except that scores for pins and hide had the least influence. Scores for overall body capacity were influenced the greatest by depth of barrel. In scoring mammary system the most emphasis was placed on fore udder, followed by rear udder and score for teats. Final score was most influenced by scores for mammary system. It was found that the relative emphasis as indicated by path coefficient analyses was strongly affected by the variability of the traits involved. The effect of age was found to be significant in this study making interpretation of the correlations more difficult. Dairy character, body capacity, body weight, and wither height all increased with age. General appearance and final score were less affected by age. Scores for mammary system decreased with advancing age. Milk yield was correlated .99 with SNF yield. Milk yield with fat yield (.92 in Holsteins and .94 in Jerseys) were higher than previously reported. Age had no significant effect on percent fat but caused a decrease in percent SNF with advancing age. Correlations of most of the components of body form with milk yield were rather low. Dairy character was correlated .46 and .15 with actual milk yield in Holsteins and Jerseys, respectively. Adjusting the milk, fat, and SNF to mature equivalents or adjusting milk to a common energy basis were not effective in increasing the correlations of body form with milk production. Dairy character was correlated .43 and -.09 with peak yield and persistency, respectively for Holstein and .26 and .01, respectively for Jerseys. Measures of body size (body capacity, body weight, and wither height) were more highly correlated with peak production than with other measures of milk production. Their respective correlations with peak yield for Holsteins and Jerseys were .25 and .17 for body capacity, .39 and .41 for body weight, and .32 and .25 for wither height. The corresponding correlations of these components with persistency were -.07 and -.01 for body capacity, -.33 and -.23 for body weight and -.23 and -.08 for wither height.

Download or read book The Effect of Milking System on Milk Production and Quality in Qu bec Dairy Herds written by Alireza Lotfi Abardeh and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The objective of this study wast o investigate the effect of milking system (automated versus parlour or milk-line) on milk production and quality in Québec dairy herds. Lactation milk, energy-corrected milk, fat, and protein yields (kg) were analysed as indicators of production, while lactation average somatic cell score was analysed as an indicator of quality. The analysed data consisted of 67,440 lactation records for 48,018 animals in 1,065 herds (712, milk-line, 216 parlour, and 137 robot). The records covered eleven geographic regions of Québec, and represented Holsteins (84%), Ayrshire (10%), Jersey (5%) and Brown Swiss (1%), over four parities. The model for analysis of each dependent variable accounted for fixed effects of milking system, breed, parity, year of calving, and geographical region of Québec, as well the random effect of herd, nested within milking system and region. Interactions between Breed x Parity and Milking System x Parity were significant in all production models, as was Milking System x Breed with the exception of Lactation Fat Yield. The three-way interaction (Milking System x Breed x Parity) was only significant for lactation average somatic cell score. Within milking system, all production traits increased with parity (the majority of the increases were significant). Within breeds, results indicated that Holsteins on robotic milking systems had higher levels of production than Holsteins milked in either conventional milking system, with the exception of fat yield from robotic milking systems (which was not significantly higher than from parlours, but was still higher than milk-lines). The only other within-breed comparison that was significant applied to Jerseys where lactation milk yield was higher from robots than milk-lines. Somatic cell score tended to increase with increasing parity, but those increases were only significant across the three milking systems in the case of Holsteins, and only for parities 1 through 3. Very few of the other parity differences were significant within breed and milking system and, in fact, Jersey least squares means for robotic milking systems seemed to decrease with parity. While the least squares means for somatic cell score tended to be slightly higher for robotic milking than conventional milking, there were no significant differences for any breed/parity combination. Results for Holstein data (which formed the vast majority of the data) would seem to indicate that robotic milking systems can provide higher production than conventional milking systems, without necessarily compromising on milk quality." --

Download or read book Causes and Prevention of Reproductive Failures in Dairy Cattle written by and published by . This book was released on 1964 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biostatistical Analysis of Factors Influencing Lactation Performance of Range Cows and Weaning Weights of Their Calves microform written by Sarah Louise Butson and published by National Library of Canada. This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation was carried out to examine trends in lactation performance and factors influencing milk traits and calf weaning weight among range beef cattle. Cows representing four beef and dairy-beef breeds and lines from the University of Alberta beef herds ranging in age from 2 to 10 years of age were used in the study. June and September measurements of milk and constituent percentages were taken on 206 and 242 cows in 1976 and 1977 respectively. Age and breed of dam, and age and sex of calf were recorded. Other variables examined were cow weight changes during gestation and lactation and birthweights, weaning weights and preweaning ADG of their calves. Milk variables and calf weaning weights were the traits studied. In Chapter I the lactation performance of the four breed groups of dams was examined. Results indicated that crossbred cows with dairy breed ancestry yielded more milk and were more persistent than a purebred traditional beef breed. Trends between breeds for constituent percentage production were less noticeable although the dairy crossbreds tended to produce less butterfat% than the purebreds. In Chapter II factors influencing milk and constituent yields were investigated using the multiple regression technique in Chapter II. Stepwise regressions involving age and breed of dam accounted for between 34.0% and 44.0% of the variance in any of the milk or constituent yields. Full and restricted regression models allowed the introduction of independent variables after adjusting for age and breed of dam effects. Calf preweaning ADG showed a high association with milk yield variables. Other factors such as calf birthweight and cow weight changes however did not account for a significant proportion of the variance in any one milk or constituent yield variable. Because associations and correlations between milk yield and calf ADG were significant but only moderately high, all factors influencing weaning weights of range calves were examined in Chapter III. Regression analysis indicated that age and breed of dam effects accounted for an average of 47% of the variance in calf weaning weight. When age and breed of dam were not considered, milk or constituent yields accounted for approximately 40% of weaning weight variance. However, milk variables still accounted for up to 10% of the variance after accounting for the effects of age and breed of dam. Calf birthweight and cow weight changes had minor effects on calf weaning weight. As a significant proportion of the variance in weaning weight was accounted for by milk variables, which in turn are largely a reflection of the breed of dam, it was concluded that selection for increased lactation performance and the introduction of dairy breeds into the breeding program of a beef herd can effect meaningful increases the weights of calves weaned.

Download or read book Effects of Feeding the Close up Dry Period Diet for the Entire Dry Period Or Three Weeks Prior to Expected Calving Date on Milk Production Milk Composition and Body Condition on Two Commercial Dairy Farms written by Luciana Laurette Contreras and published by . This book was released on 2002 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Milk Production in Dairy Cattle written by Vaughn Stewart Logan and published by . This book was released on 1939 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Genetic Selection in Canadian Dairy Cattle written by Bernard Hagan and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Genetic evaluations for April 2018, which were computed by Canadian Dairy Network, dairy herd information, and lactation records of Holstein cows from Lactanet, were used to (i) compute realized genetic selection differentials (GSD) for economically important traits in Holstein, Ayrshire, Jersey, and Brown Swiss herds in Canada, (ii) investigate generation intervals in four dairy cattle populations, (iii) estimate genetic parameters for milk production, lactation body weight, SCS, and profit indicator traits in Holstein cows in Québec, and (iv) develop a prototype tool and visualization model to monitor selection realized in individual dairy herds. A new approach that would be more relevant to dairy producers has been used to compute realized GSD of traits of economic importance in four dairy cattle breeds in Canada. Significant GSDs were being realized for production, durability, health, fertility traits, and lifetime performance index (LPI). Greater selections were realized in the dam-to-bull (DB) and sire-to-bull (SB) pathways of selection compared with selection realized in the sire-to-cow (SC) and dam-to-cow (DC) pathways; little to no selection was realized for production, durability, and health traits in the DC path in the four dairy cattle breeds. Apart from year of conception, other non-genetic factors were mostly unimportant on the realized GSD for economically important traits while significant variations existed among herds in their realized GSD.Generation intervals (L) in all four paths of selection have been decreasing from 1980 to 2016. There have been 55%, 41%, 46%, and 38% reductions in total L in the Holstein, Ayrshire, Jersey, and Brown Swiss populations between 1980 and 2016, respectively. A significant proportion of the reductions in L occurred in the last 8 years (2009 to 2016). Herd and herd*year of birth explained significant proportion of the variations in L. This study has demonstrated that herds that used younger Artificial Insemination bulls for breeding increased their annual genetic progress at a faster rate.First to fourth lactation records of Holstein cows in Québec were used to estimate genetic and phenotypic parameters of milk production, somatic cell score (SCS), lactation body weight (BWT), cumulative milk value (MV), cumulative feed cost (FC), and margin over feed cost (MOFC). Heritability estimates for milk production traits, BWT, MV, and MOFC were moderate whereas heritability estimates for SCS and FC were low. Genetic correlations among the traits studied ranged from low to high. Strong genetic correlations existed between the same traits in different lactations with the greatest correlations found between adjacent lactations. An attempt has been made to illustrate that it is possible to slow or halt the positive genetic trends in cow body weight by incorporating BWT and milk production traits into a simple selection index.Finally, a prototype software tool and visualization model were developed to help dairy producers and advisors monitor GSD in their herds, and compare the selection they are making with a number of benchmarks. The concept of this prototype software tool is applicable to all livestock species for which genetic evaluations are routinely computed and published. It is expected that producers would use this software tool to monitor what selection they are making in their herds and make changes if they are moving in an unintended direction"--

Download or read book Effects of Calf Rearing and Genetics for Resilience on Milk Yield and Health in Dairy Cattle written by Kirsten Elzinga and published by . This book was released on 2022 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Season on Fat Test and Milk Production of Dairy Cows written by Frank Burdette Headley and published by . This book was released on 1933 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: