Milk Yield During the First Four Months of Lactation and Cow Pro- ductivity of Brahman and Tuli Beef Cattle in South-East Botswana

The climate of Botswana because of its semi-aridity, is mostly suitable for livestock farming, especially beef cattle production under extensive grazing conditions. The major indigenous cattle breed is the Tswana, while the Tuli (TT) and Brahman (BB) are popular and increasing in numbers to the cattle population of 2.5 million. In the present study, the TT (n=15) and BB (n=24) breeds were compared for cow productivity and milk production using the weigh-suckle-weigh technique. The TT cows produced more milk than BB cows (12.4 vs 9.2 kg/d) during the first four months of lactation. However, BB cows produced heavier (P < 0.001) calves at weaning than TT cows (164.8 vs 150.4 kg). Similarly, BB cows produced faster (P < 0.001) growing calves than TT cows (.69 vs.64 kg/d). Across breeds, calves born earlier in the season had a higher (P < 0.01) average daily gain (ADG) than those born later in the season (.69 vs.64 kg/d). It is an advantage to producers to have the majority of calves born early in the calving season (September/October) so that calves are bigger and heavier at weaning than those calves born late in the season (November/December)