Effect of birth date on growth performance of calves of seasonally-bred range cattle

Traditional livestock in semi-arid north eastern Zimbabwe: Mashona cattle

Productivity data were gathered from Mashona cows (n = 187) in 28 traditionally managed herds in two areas, separated by a corridor 20-30 km wide of almost uninhabited bush in NE Zimbabwe. Cattle are kept primarily to provide oxen for work. Cows in the southern area, which had been more affected by drought in 1991-92, were younger (7.2 vs. 9.1 years) and had a longer median calving interval (548 vs. 406 days). Metrical data (n = 105 cows) showed these cattle to be larger-bodied than those in the northern area (heart girth 146 vs. 144 cm). Market prices, estimated by respondents, were higher for oxen and herds were smaller in the south, and calf survival was believed by owners to be more influenced by season of birth in this area. Data were obtained on 531 calves. Before the age of 12 months 6.2% died, a low proportion compared with other studies. Most were retained in herds but 11.5% were slaughtered, sold or given away. All owners practised castration, selecting fast growing, strong bull calves for breeding.