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Showing 1 to 20 of 126 for “"sire"”.
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The impact of sire daughter variability and repeatability on the accuracy of sire selection
Modified contemporary sire evaluation procedures, using first lactation records only, were used to compute Predicted Differences for all Holstein bulls having 10 or more daughters calving in any calendar year between January 1964 and June 1973. Significant heterogeneity of within sire daughter milk …
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Evaluation of terminal sire breeds for hair sheep production systems
Terminal sire crossbreeding systems which improve growth performance while maintaining parasite resistance have the potential to enhance the profitability of hair sheep enterprises. Katahdin (KT, n = 4), Suffolk (SU, n = 3), and Texel (TX, n = 3) rams were randomly mated to KT ewes over two years …
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Effect of sire line and rate of gain on pork quality
Terminal sire selection is a critical factor in modern day swine production as it has the ability to influence characteristics that affect the financial stability of the producer and packer while concomitantly influencing the eating experience of the consumer. Pietrain pigs are often utilized in …
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Residual feed intake, breed of sire and dam, and individual sire affect performance and carcass characteristics and rates of back fat and intramuscular fat of feedlot steers
… G:F (P = 0.02). The interaction between breed of sire and dam had no significant (P > 0.05) effect on any of the performance characteristics analyzed. Steers from Angus sires had 23% (0.33 cm, P < 0.0001) higher carcass back fat (BF) than steers from Simmental sires. Steers from Angus sires had …
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Improvement in accuracy using records lacking sire information in the animal model
… genetic evaluations by including records lacking sire identification. Methods 1 and 2 assumed genetic values of cows missing sire identity were population and management group average, respectively. Methods 3 and 4 accounted for genetic values through producing abilities estimated as random and …
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Factors affecting the accuracy and stability of sire proofs from progeny test herds
… of their bulls' proofs examined, their young sire sampling program was investigated. Individual phenotypic and genetic records of first crop and non-first crop cows in 3449 herds participating in the AI stud's young sire sampling program from 1971 to 1987 were used to characterize the sampling …
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The Interaction of Sire Fertility and Timing of AI in a Synchronization Protocol
… rate (PR) when average and high fertility sires were used. Additionally, a second experiment was conducted to determine the effectiveness of CIDR inserts to allow for resynchronization of estrus in cows that did not conceive or maintain the conceptus at FTAI. Lactating Holstein cows (n = …
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Utility of inbreeding coefficient and sire as predictors for osteochondrosis risk in Standardbred horses
… genetic risk at the level of the individual. Sire effects on risk of OC have been reported, but inbreeding coefficient has not been examined as predictor for genetic risk of disease. We investigated this in a cohort of 910 Standardbred yearlings fluoroscopically screened for osteochondral …
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Index selection in terminal sire sheep: implications for genetic improvement in a crossbreeding system
Using terminal sires for crossbreeding is standard practice in the UK sheep industry, where over 70% of market lambs have terminal sire breeding. Thus, selection focusing on terminal sires will translate to changes in the entire industry. Consumers perceive lamb meat as fatty and demand for it has …
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Analysis of the effects of sire and age on wool quality traits in Romney ewes
… decreased (hogget x̄=13.7%, two tooth x̄=6.4%). Sire was recorded for 181 ewes, which allowed the performance of sires to be compared for each wool trait. Sire significantly affected MFD, staple length, mean curvature, and coarse edge (p=<0.001), as well as the coefficient of variation of MFD …
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Improving pedigree prediction, sire, and cow evaluation by adjusting production data for past reproductive performance
… open. Model I included the mean, HYS, groups, sires of herdmates (fixed) and young bulls within groups (random). In model II, the same effects were used considering all bulls and sires random with adding the relationship among bulls. Data were 24,997 progenies of 484 young bulls and 119,013 …
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Evaluating Economic and Environmental Impacts of Changing Herd Sire Genetics on Arkansas Cow-Calf Operations
<p>This research looks at impacts of changing sires, and thus bull genetics, on cow-calf operations of varying land and herd sizes in the state of Arkansas. A 2012 Across-Breed EPD table, adjusted to the Angus breed, was used to estimate breed sire effects on birth weight and weaning weight of the …
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A comparison of herdmate, iterative, and mixed model sire summaries for type in Holstein cattle
… adjusting for average PDT of herdmates' sires and average cow index of herdmates respectively, and a mixed model method. PDTs were calculated using the different methods for 6816 bulls with ten or more daughters. Mean PDT for the herdmate comparison was -.18 while means for the two …
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Impact of sire PTA<SUB>SCS</SUB> on mastitis resistance and measures of daughter performance
Research to determine the impact of PTA<SUB>SCS</SUB> on incidence of mastitis, daughter response to infection, and other measures of daughter performance was conducted using data on 1st, 2nd, and 3rd lactation Holsteins obtained from the Virginia Tech herd and from VA DHI herds. Overall …
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Relative influence of the sire and dam upon the inheritance of speed in standard trotting horses
… have been secured upon the relative influence of sire and dam in the production of offspring. From the limited data collected various conclusions have been drawn, but as yet there is needed more accurate information before the problem will have been solved. This work then is presented in an …
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Effect of sire line and rearing environment on the growth performance and carcass characteristics of growing-finishing pigs
The effects of sire line and rearing environment on the growth performance and carcass characteristics of growing-finishing pigs were evaluated using 208 barrows from 2 purebred sire lines. The study was conducted as a randomized complete block design (blocking factor was the day of start of test) …
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Use of sire evaluations for first, all, and later lactations to predict lifetime profit functions of individual daughters
Sire evaluations from first, all, and later lactations for Predicted Difference milk, fat, and dollars on 226 sires were used to predict deviated relative net income. Eleven different relative net incomes were calculated on 176,902 individual cows. Low, medium and high values were used for lifetime …
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Effect of sire line and selection index category on pig growth performance from weaning to harvest and carcass characteristics
The objective of this study was to compare 3 sire lines and the effect of selection index category within sire line on growth performance (from 6.1 ± 0.29 to 129.8 ± 2.16 kg BW) and carcass characteristics of pigs under commercial conditions. A randomized complete block design (blocking factor …
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An analysis of sire-son and dam-daughter relationships for type traits in the Holstein descriptive type classification system
… of the son progeny test on that of his sire indicated that head, front end, hind legs, feet, rear udder, and udder quality were poor indicators of son's performance when the sire's progeny test result was used for selection decisions. Considerable emphasis was placed on type in selecting …
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Characterizing the amount and variability of intramuscular fat deposition of pork loins using barrows and gilts from two sire lines
… 4 pigs each. Equal numbers of barrows and gilts sired by boars targeting meat quality or lean growth were used. All pigs were fed the same corn-soybean diet formulated to meet or exceed nutrient requirements based on the 2012 National Research Council requirements of swine, for a 3-phase feeding …
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