Ilatsia E.D., Muasya T.K., Muhuyi W.B., Kahi A.K.
Animal Genetic Resources Group, National Animal Husbandry Research Centre, Kenya Agricultural Research Institute, Naivasha, Kenya; National Beef Research Centre, Kenya Agricultural Research Institute, Nakuru, Kenya; Animal Breeding and Genetics Group, Department of Animal Sciences, Egerton University, PO Box 536, Egerton 20115, Kenya
Ilatsia, E.D., Animal Genetic Resources Group, National Animal Husbandry Research Centre, Kenya Agricultural Research Institute, Naivasha, Kenya; Muasya, T.K., Animal Genetic Resources Group, National Animal Husbandry Research Centre, Kenya Agricultural Research Institute, Naivasha, Kenya; Muhuyi, W.B., National Beef Research Centre, Kenya Agricultural Research Institute, Nakuru, Kenya; Kahi, A.K., Animal Breeding and Genetics Group, Department of Animal Sciences, Egerton University, PO Box 536, Egerton 20115, Kenya
The aim of this study was to evaluate milk production and reproductive performance of Sahiwal cattle in semi-arid Kenya. Milk production traits considered were lactation milk yield, lactation length and test-day milk yield, while reproductive traits included age at first calving, calving interval and number of services per conception. Various fixed effects affected performance of milk production and reproductive traits to varying significance levels. The mean estimates for milk production traits were 1368 kg, 282 days and 4.9 kg for lactation milk yield, lactation length and test-day milk yield, respectively. For reproductive traits, mean estimates were 468 days, 2.2 and 1345 days for calving interval, number of services per conception and age at first calving, respectively. There was a decline in lactation milk yield and lactation length, and an increase in calving interval and age at first calving over the years. Satisfactory management and appropriate genetic improvement strategies would result in improved performance. Implications of the results for genetic improvement of the breed in Kenya are discussed. Copyright © 2007 John Wiley & Sons, Ltd.