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Full-Text Articles in Life Sciences
Genetic And Phenotypic Parameters For Carcass Traits Of American Shorthorn Beef Cattle, F. Pariacote, R. E. Hunsley, L. Dale Van Vleck
Genetic And Phenotypic Parameters For Carcass Traits Of American Shorthorn Beef Cattle, F. Pariacote, R. E. Hunsley, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Carcass measurements were taken on 1,292 steers and collected by the American Shorthorn Association. The sires were purebred or appendix-registered Shorthorn. Because all dams were not Shorthorn, genetic fractions of breeds of origin were determined for each dam. Measurements for hot carcass weight; dressing percentage; fat thickness; ribeye area; kidney, pelvic, and heart fat (KPH); marbling; and yield grade were analyzed jointly with a multivariate REML algorithm to estimate heritabilities of and genetic and phenotypic correlations among the traits. The sire model chosen as best fit of the data included fixed effects of herd of origin (377 classes), slaughter group …
Parameter Estimates For Direct, Maternal, And Grandmaternal Genetic Effects For Birth Weight And Weaning Weight In Hereford Cattle, J. Dodenhoff, L. Dale Van Vleck, Stephen D. Kachman, R. M. Koch
Parameter Estimates For Direct, Maternal, And Grandmaternal Genetic Effects For Birth Weight And Weaning Weight In Hereford Cattle, J. Dodenhoff, L. Dale Van Vleck, Stephen D. Kachman, R. M. Koch
Department of Animal Science: Faculty Publications
Birth and weaning weights adjusted for age of dam from four lines of Hereford cattle were analyzed to determine the relationships among grandmaternal, maternal, and direct genetic effects. Three lines were selected for 1) weaning weight (WWL), 2) yearling weight (YWL), and 3) an index of yearling weight and muscle score (IXL). The fourth line was an unselected control line (CTL). Numbers of observations ranged from 1,699 (CTL) to 2,811 (WWL), and number of animals in the pedigree file ranged from 2,266 to 3,192. Two animal models were used to obtain estimates by REML using an average information method. Model …
Sex Effects On Breed Of Sire Differences For Birth, Weaning, And Yearling Weights, L. Dale Van Vleck, Larry V. Cundiff
Sex Effects On Breed Of Sire Differences For Birth, Weaning, And Yearling Weights, L. Dale Van Vleck, Larry V. Cundiff
Department of Animal Science: Faculty Publications
Weights of males and females can be considered to be correlated traits with different averages and variances. This study attempted to determine whether defining traits as expressed in males or in females would change estimates of breed of sire differences needed to calculate across-breed factors for adjustment of within-breed EPD to across-breed EPD. Records from the US Meat Animal Research Center of progeny of Hereford, Angus, and MARC III composite dams mated to 12 sire breeds that had been used to calculate breed of sire adjustments in 1996 were used. Breeds of sire were Hereford, Angus, Shorthorn, Brahman, Simmental, Limousin, …
Comparison Of Sire Breed Solutions For Growth Traits Adjusted By Mean Expected Progeny Differences To A 1993 Base, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff, D. S. Buchmann, D. M. Marshall
Comparison Of Sire Breed Solutions For Growth Traits Adjusted By Mean Expected Progeny Differences To A 1993 Base, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff, D. S. Buchmann, D. M. Marshall
Department of Animal Science: Faculty Publications
Records on growth traits were obtained from five Midwestern agricultural experiment stations as part of a beef cattle crossbreeding project (NC-196). Records on birth weight (BWT, n =3,490), weaning weight (WWT, n = 3,237), and yearling weight (YWT, n = 1,372) were analyzed within locations and pooled across locations to obtain estimates of breed of sire differences. Solutions for breed of sire differences were adjusted to the common base year of 1993. Then, factors to use with within-breed expected progeny differences (EPD) to obtain a crossbreed EPD were calculated. These factors were compared with factors obtained from similar analyses of …
Effect Of Ignoring Random Sire And Dam Effects On Estimates And Standard Errors Of Breed Comparisons, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff
Effect Of Ignoring Random Sire And Dam Effects On Estimates And Standard Errors Of Breed Comparisons, K. L. Barkhouse, L. Dale Van Vleck, Larry V. Cundiff
Department of Animal Science: Faculty Publications
Data were weights of F1 calves and weaning weights of top-cross progeny from sires and maternal grandsires of 13 breeds. Three analyses were performed on each trait to obtain estimates and standard errors of breed effects needed to calculate across-breed EPD and accuracies. Model (R) for records of F1 progeny contained fixed effects for birth year and date of birth, sex, age and breed of dam, and breed of sire, and a random residual effect. The second analysis included random effects for sires (RS), and the third analysis included random effects for sires and dams (RSD). In maternal …
Effects Of Inbreeding And Heterozygosity On Preweaning Traits In A Closed Population Of Herefords Under Selection, L. Dale Van Vleck, M. D. Macneil
Effects Of Inbreeding And Heterozygosity On Preweaning Traits In A Closed Population Of Herefords Under Selection, L. Dale Van Vleck, M. D. Macneil
Department of Animal Science: Faculty Publications
Records of five inbred lines at the Livestock and Range Research Laboratory were used to evaluate effects of inbreeding and heterozygosity on preweaning traits. Members of each line were descendants of a single founder Hereford bull. A total of 8,065 records of birth weight and 7,380 records of preweaning daily gain and weaning weight were analyzed by derivative-free REML using a model that included fixed effects of sex, combination of year and month of birth and parity of dam, with covariates for direct and maternal genetic fractions of inheritance from the genetic groups, inbreeding, and heterozygosity fractions. Heterozygosity fractions were …