Crossbreeding beef cattle in Western Uganda. 1. Performance of Ankole, Boran and Zebu Cows

Abstract

SUMMARYIn a new ranching area of Uganda recently cleared of trypanosomiasis, with a high level of disease control, adequate water supplies and extensive grazing on free range, three dam breeds, the indigenous Ankole and Zebu, and the Boran from Kenya, were mated to Boran, Angus and Red Poll sires.Under artificial insemination, at least 10 % fewer cows were detected on heat than under natural service, and 15% fewer artificially inseminated cows actually produced calves than did naturally served cows. The introduced Boran females were not inferior in calving percentage to the indigenous Ankole and Zebu.Relationships between dam body weight and progeny performance were investigated. The introduced Boran breeding cows were able to maintain their body weight as least as well as the indigenous Ankole and Zebu cows. While cows which calved regularly and reared their calves could not maintain body weight, it was found that heavier cows conceived at a higher rate than lighter cows, cows heavier at parturition weaned heavier calves than lighter cows, and cows that reared heavier calves lost more, or gained less, body weight than cows that reared lighter calves. It was therefore indicated that investigations into the reduction of lactation stress on cows by such methods as earlier weaning of calves, mating at the most suitable time of year, and possible nutritional supplementation at a stage in the cycle, should be commenced.

Crossbreeding cattle in beef production programmes in Kenya. II. Comparison of purebred Boran and Boran crossed with the Red Poll and santa gertrudis breeds

“…The ½ RP-½ B and ½ SG-V2 B breed groups were produced by mating Red Poll and Santa Gertrudis sires on Boran cows. Data were collected on breeds groups series I in 1971I in , 1972I in and 1973I in and on breed group series II in 1971I in , 1972I in , 1973I in , 1974I in and 1975. The Boran and the ½ RP-½ B breed group cows present in 1971, 1972 and 1973 contributed data to both data sets.…”

“…Purebred Boran cows were included in each breed group because the Boran breed has long been regarded as a standard for comparison in beef production programmes in East Africa (Trail, Sacker and Fisher, 1971;Gregory, Trail, Marples and Kakonge, 1984a). Heterosis from breed crosses is of major economic importance for both individual and maternal traits (Gregory and Cundiff, 1980;Cartwright, Ellis, Kruse and Crouch, 1964;Koger, Peacock, Kirk and Crockett, 1975).…”

Conception rates of beef cattle in Botswana following synchronization of oestrus with cloprostenol

“…In Botswana, large areas of the country are suitable only for extensive beef cattle production and, with the development of ranching production systems, AI could play a useful role in breed improvement (Buck, Serema and Staugaard, 1975). Where AI has been used as the sole method of breeding ranch cattle, poor herd pregnancy rates have resulted (Trail, Sacker and Fisher, 1971). Where AI has been used as the sole method of breeding ranch cattle, poor herd pregnancy rates have resulted (Trail, Sacker and Fisher, 1971).…”

Crossbreeding beef cattle in Western Uganda 4. Calving percentage and mothering ability

“…A description of environmental conditions on the Ankole Ranching Scheme and the method of production of crossbred heifers has been given by Trail, Sacker and Fisher (1971a The first crop of crossbred females born in 1965, comprising a total of 137 animals of all 9 possible combinations of progeny from Angus, Boran and Red Poll sires crossed on to Ankole, Boran and Small East African Zebu females, were mated to Friesian bulls over a 4-month period, at the beginning of which the heifers averaged 21 months in age and 228 kg live weight compared with 25 months and 261 kg at the end. The average calving age of 32 months is considered about the earliest possible under present environmental conditions on the ranching scheme.…”