Heritabilities and genetic correlations of male and female traits, in a Canchim beef cattle herd

The objective of this study was to estimate the heritabilities and the genetic correlations of body weight (BW12) and scrotal circumference (SC12) of males at twelve months of age and culling age (DH, days in herd) of females, and number (NW10) and kilograms (KW10) of weaned calves produced by females up to ten years of age, in a Canchim (5/8 Charolais + 3/8 Zebu) beef cattle herd. Data were composed of 1370, 826, 826, 2726 and 1051 observations of DH, NW10, KW10, BW12 and SC12, respectively. The variance and covariance components were obtained by the bayesian method, with a statistical model that included, besides the additive direct and residual random effects, the fixed effects of year of birth for all traits, month of birth for BW12 and SC12, and the covariate age for SC12. The heritability estimates, obtained by the one-trait analyses, were equal to 0.38, 0.52, 0.24, 0.33 and 0.34 for BW12, SC12, DH, NW10 and KW10, respectively, indicating that all traits have enough genetic variability to show response to selection. The genetic correlations of DH (0.33 and 0.33, respectively), NW10 (0.38 and 0.30, respectively) and KW10 (0.61 and 0.41, respectively) with BW12 and SC12, obtained by the two-trait analyses, suggest that selection for increased body weight and scrotal circumference of the males at twelve months of age will not result in decreased days in herd for the females, and decreased number and kilograms of weaned calves produced by the females up to ten years of age.