The objective of this study was to estimate heritability and genetic correlations for body weight at birth (BW), weaning (WW), twelve (W12) and eighteen (W18) months of age, weight gains from birth to weaning (DGBW) and from birth to eighteen months of age (DGB18), days to 175 kg from birth to weaning (D175 = 175/DGBW), days to 450 kg from birth to slaughter (D450 = 450/DGB18) and female mature body weight (ABW) using data from a herd of Canchim (5/8 Charolais + 3/8 Zebu) cattle. Univariate and bivariate models including the fixed effects of year and month of birth, sex of calf, year and month of calving, age at calving, age of dam as a covariate (linear and quadratic components) and additive, maternal, permanent environmental and residual random effects were fitted by REML. Heritability estimates obtained by univariate analyses were 0.41 (BW), 0.28 (WW), 0.38 (W12), 0.28 (W18), 0.26 (DGBW), 0.30 (DGB18), 0.23 (D175), 0.23 (D450), and 0.48 (ABW). Genetic correlation estimates ranged from 0.28 to 0.97 between body weight traits, from 0.11 to 0.97 between body weight traits and weight gains, from 0.00 to -0.98 between body weight traits and D175 and D450, and from -0.63 to -0.98 between weight gains and D175 and D450. Genetic correlation estimates were 0.69 between DGBW and DGB18, and 0.76 between D175 and D450. Genetic progress for growth in Canchim cattle is possible by direct as well as by indirect selection on any trait evaluated in this study.
beef cattle; body weight; genetic correlation; heritability; weight gain
