The objective ofthis study was to evaluate the genotype × environmentinteraction for weaning and yearling weights, daily weight gain from weaningto 12 months of age and the growth performance in Canchim (5/8 Charolais + 3/8Zebu) beef cattle estimated by a principal components analysis including thosethree traits. The environment was defined by season of birth (first and secondsemesters of the year). Genetic parameters were estimated by bayesian methodwith the Gibbs sampler using bivariate analyses (considering the trait in eachof the two seasons as a different one) and models that included the fixed effectsof year and month of birth, sex and age of cow (linear and quadratic) and therandom effects of animal and residual. The results suggested that genetic evaluationand selection in Canchim beef cattle for the traits studied should considerthe genotype and season of birth interaction.
