Abstracto
- The aim of this study was to estimate the components of (co) variance and genetic parameters for birth weight (BW), weaning weight (WW) and weight at 16 months (W16), using different models unicaracter in a population of cattle Creole Costeño con Cuernos (CCC). 3060 records of BW, 2594 of WW, and 1990 of W16 were used. Six statistical models were applied, which included the fixed effects of contemporary group (year-season-sex-parity) as covariate and age at weaning and 16 months. The direct additive genetic random effect of the animal was common to all models and maternal additive genetic effects, maternal permanent environmental, and genetic covariance between direct and maternal effects were alternated. Estimates of components of variance were performed using the program ASREML.According to the test of likelihood ratio, the best model was the one that included the random effects of animal, maternal and maternal permanent environment, also the covariance between direct and maternal effects. Estimation of direct and maternal heritabilities varied between different models for each of the traits analyzed. Genetic correlations between direct and maternal effects for BW were positive (0.81 to 0.98) and negative for WW (-0.30 to -0.35) and W16 (-0.12). According to the estimates of heritability for the traits, should improve the conditions of feeding and management, to enhance the expression of these traits in the population. © 2015, Fundacion CIPAV. All rights reserved.
