Resumen de GM 03. Heritability of scrotal circumference adjusted and unadjusted for body weigth in Nellore bulls using uni and bivariate animal model
Célia Raquel Quirino, Jose Aurelio Bergmann
Mixed model methodology under uni and bivariate animal models were used to estimated genetic parameters of scrotal circumference (SC) adjusted (h2AJ) and unadjusted (h2NAJ) by body weigth (BW), of 875 Nelore bulls. Fixed effects of age of dam, year of birth, month and year at measurement with covariate age for model 1 and with covariate age and body weigth for model 2 were analyzed. Heritability estimates using univariate model for h2AJ were .15, .60, .71 and .50 and for h2NAJ were .18, .65, .77 and .60 at 9, 12, 18 and 24 months, respectively. The bivariate h2AJ ranged from .13 and .70 and for h2NAJ ranged from .18 to .77. Genetic correlations varied from .33 and .71 for SC and BW. Estimates of h2NAJ might be the best parameters to be included in the future programs of breeding.
