Evaluation of beef breeds for rangeland weaner production in Zimbabwe 1. Productivity of purebred cows

Abstract

ABSTRACTPurebred cows were evaluated for reproductive performance and live weight, and for pre-weaning growth and viability of crossbred progeny sired by unrelated breeds. The cows comprised three indigenous breeds, Mashona, Nkone and Tuli and four exotic breeds Africander, Brahman, Sussex and Charolais. Over 3 years, the mean calving rates % (s.e.) were 55·5 (3·0), 76·0 (3·8), 63·1 (4·5), 69·6 (3·5), 70·0 (3·8), 60·0 (4·3) and 67·0 (5·0) for Africander, Mashona, Nkone, Tuli, Brahman, Sussex and Charolais cows, respectively.Bos taurusand Brahman cows were heavier at parturition and at calf weaning than indigenous cows. Mashona cows were lightest at both stages. Calves ofBos tauruscows were heaviest at birth and those of Mashona lightest. Calves of Brahman cows had the most rapid growth rate and at weaning (240 days) weighed in kg (s.e.) 207 (3·1), compared with 184 (2·1), 172 (2·2), 187 (2·6), 184 (2·1), 178 (2·7) and 186 (2·9) for progeny of Africander, Mashona, Nkone, Tuli, Sussex and Charolais, respectively. Pre-weaning survival rates of the breeds were not significantly different but viability was higher in progeny of indigenous than exotic breeds. The productivity estimates combining calving rate, cow weight, calf weaning weight and pre-weaning viability demonstrated the superiority of indigenous breeds and the Brahman over Africander andBos taurusbreeds.