Maternal influence from birth to yearling in Guzerá cattle. II. Heritabilities and genetic correlations between direct and maternal effects

Abstract

Data collected at the Canoas Farm (State of Minas Gerais, Brazil), from 635 Guzerá calves – 380 males and 255 females – out of 26 bulls and 194 cows, were analyzed. The analysis consisted of estimating correlations between genetic direct and maternal effects and the heritabilities of the direct effects (h²_MIP and h²_MIM), maternal effects (h²_Am) and total heritability (h²_t). The h²_MIP were 0.15, 0.23 and 0.25 and h²_t were 0.29, 0.10 and 0.23 for birth, weaning and yearling weight, respectively. The h²_Am (0.81) was bigger than h²_MIP (0.23), for weaning weight. The genetic correlations between direct and maternal effects was positive for birth weight and negative for 205 and 365-days weight, indicating genetic antagonism between those effects for weaning weight, and, in smaller proportion, for yearling weight and the necessity to consider maternal effects in selection procedures to maximize genetic responses.