DEVELOPMENT OF BREEDING OBJECTIVES FOR PRODUCTION SYSTEMS UTILISING THE BORAN BREED IN KENYA

Abstract

Boran cattle are important in the Arid and Semi-Arid Lands (ASALs) of Kenya for beef production and as a source of livelihood to pastoralists as dual purpose animals providing both milk and meat. Despite their importance, no formal breeding objectives exist. The aim of this study was to develop breeding objectives for production systems utilising the Boran. Six systems were described by sale age of animals, levels of input and final goal as; short fed medium input beef (SFMB); long fed medium input beef (LFMB); short fed high input beef (SFHB); long fed high input beef (LFHB); long fed low input dual purpose (LFLD) and long fed medium input dual purpose (LFMD). Bio-economic profit functions were constructed and subsequently used to derive economic values of breeding objective traits under fixed herdsize and fixed pasture input situation. The traits were classified into production (sale weight of steers – SWs and heifers - SWh; dressing percentage – DP; consumable meat percentage – CMP, and milk yield – MY) and functional traits (cow weight – CoWT; cow survival rate – CoSR; post-weaning survival rate – PSR; feed intake of cows - FIc, heifers - FIh and steers - FIs). The influence of the estimated economic values on genetic improvement was also assessed using different selection indices. The outputs from the profit functions included revenue, costs and feed intake of cows, heifers and steers in the different production systems. In the fixed herd-size situation, the economic values for production (except MY in pure beef systems) and functional traits (except feed intake in all systems) were positive meaning a unit increase in genetic merit of these traits had greater influence on revenues than costs. The economic value of MY was negative in the pure beef systems (SFMB, LFMB, SFHB and LFHB) and positive in the dual purpose systems (LFLD and LFMD). Economic values estimated in the fixed pasture input situation were lower than those under fixed herd size for feed intake in the three classes of livestock and other traits related to feed intake namely, CoSR, CoWR, PSR, CoWT, SWh and MY in all systems. The economic values of CoWT in the LFLD and LFMD systems were negative (KSh -11.14 and -15.33, respectively). The magnitude of the economic values for production and functional traits estimated in this study suggest that genetic improvement would have a positive effect on profitability of Boran cows kept in dual-purpose systems and when herd-size is restricted. In pure-beef systems, genetic improvement of MY would have a negative effect on profitability, especially when restrictions on herd-size and feed exist.