Influência do grupo genético sobre o crescimento pré-desmama de bovinos cruzados Blonde D’Aquitaine X Nelore.

Abstract

The d>bjective of this study was to evaluate birth weight (BW), weaning weight (WW) and average daily gain from birth to weaning (ADG) of Blonde d'Aquitaine (B) x Nellore (N) crossbred calves. The calves, 114 B + 3/4 N, 3/8 B + 5/8 N, 3/4 B + 114 N e 7/8 B + 1/8 N, were sired by Blonde d'Aquitaine and Nellore bulls mated to Y2 B + Y2 Nand 3/4 B + 114 N cows. The observations were analyzed by the least squares method with a model that included the effects of year and month of birth, sex, age of cow, genetic group of sire (GGS), genetic group of dam (GGD) and GGS x GGD. Even though the interaction was significant for all three traits, the 3/4 B + 114 N cows produced heavier calves at birth and lighter calves at weaning independently of GGS. The effects of GGS can not be attributed to the breed of sire due to the occurrence of preferential matings. The least square means for BW, WW and ADG were, respectively, 30.9:t 0.1, 189.4:t 1.1 and 0.660:t 0.004 (114 B + 3/4 N), 32.2:t 0,2'- 183.2:t 1.4 and 0.629:t 0.006 (3/8 B + 518 N), 34.0:t 0.1, 208.2:t 0.7 and 0.726:t 0.003 (3/4 B + 114 N), and 36.0 :t 0.2, 198.0 :t 1.5 and 0.675 :t 0.006(7/8 B + 1/8 N).