Reproductive performance of cows mated to and preweaning performance of calves sired by Brahman vs alternative subtropically adapted breeds.

Abstract

Comparisons involving Brahman and Brahman-derivative (Brangus, Santa Gertrudis, Beef-master, Simbrah, Braford) sires indicate the following: 1) cows mated to Brangus and Santa Gertrudis bulls had a shorter gestation length than cows mated to Brahman bulls, 2) calves sired by Brangus and Beefmaster bulls were lighter at birth and weaning than calves sired by Brahman bulls, and 3) birth and weaning weights were similar for calves sired by Santa Gertrudis and Brahman bulls and for calves sired by Simbrah and Brahman bulls. Comparisons involving Brahman and other Zebu (Sahiwal, Nellore, Gir, Indu-Brazil, Boran, Romana Red) sires indicate that gestation length was slightly longer for cows mated to Sahiwal and Nellore bulls and that, relative to the Brahman, birth and weaning weights were similar to or lighter for calves sired by bulls of the other Zebu breeds. The only exception to this pattern was birth weight of Indu-Brazil-sired calves, which were heavier than calves sired by Brahman bulls. Comparisons involving Brahman and non-Zebu subtropically adapted (Tuli, Senepol) sires indicate that cows mated to Tuli bulls had a slightly shorter gestation length than cows mated to Brahman bulls and that birth and weaning weights of calves sired by Tuli and Senepol bulls were lighter than those of calves sired by Brahman bulls.