Abstracto

Derivation of economic weights of milk components as selection criteria for genetic improvement of dairy animals.

Gwaza DS, Mohammed G, Addas PA

Economic weights of milk yield, protein and fat percent for Holstein Friesian Bunaji crossbreds and Holstein Friesian dairy cows in North Central Nigeria were studied. Economic data collected were Fixed cost (N/year), feed cost (N/year), calf price (N/calf) and milk price (N/litre) Technical data were fertility (calving/per year/cow), prolificacy, longevity (year), milk yield (kg/cow in flock), fat and protein yield (kg/lactation) and fat and protein contents (%) from two government (National Veterinary Research Institute Vom and Agricultural Services and Training Centre, Jos) and two commercial private farms (Farm Fresh Jos and Nagari Farm, Keffi). Profit equations were used to predict the economic weights of primary components of milk (fat, protein and carrier). The values obtained were 163.15, 234.94, 147.05, 226.10, 261.05, 334.42, 242.42, 314.84, -4.42, -4.42, -4.42, -2.84, respectively. Results indicated that economic values for protein were higher in all the farms than any other components of milk. For carrier economic weights were negative in all the farms because an increase in carrier production without changes in fat and protein composition leads to an increase in energy demands, holding the sale price of milk constant. Given the economic importance of protein component of the milk, it should be given higher weight during selection for breeding program.