Genetic Parameter Estimates for Calving Difficulty and Birth Weight in a Multi-breed Population
نویسندگان
چکیده
Birth weight (BWT) and calving difficulty (CD) were recorded on 4,580 first parity females from the Germplasm Evaluation (GPE) program at the U.S. Meat Animal Research Center. Both traits were analyzed using a bivariate animal model with direct and maternal effects. Genetic groups for breed of AI sire were fitted to estimate breed differences. Bos Indicus influenced breeds tended to have the largest BWT. Heritability estimates for BWT direct, CD direct, BWT maternal and CD maternal were 0.45 (0.09), 0.40 (0.09), 0.18 (0.08), and 0.18 (0.08), respectively. Genetic correlation estimates were positive between direct BWT and CD direct at 0.82 (0.10). All other genetic correlations were not significant.
منابع مشابه
Breed effects and genetic parameter estimates for calving difficulty and birth weight in a multibreed population.
Birth weight (BWT) and calving difficulty (CD) were recorded on 4,579 first-parity females from the Germplasm Evaluation Program at the U.S. Meat Animal Research Center (USMARC). Both traits were analyzed using a bivariate animal model with direct and maternal effects. Calving difficulty was transformed from the USMARC scores to corresponding -scores from the standard normal distribution based ...
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