GENETIC EVALUATION OF FEMALE REPRODUCTIVE PERFORMANCE

摘要

Fertility or reproductive performance is one of the most important components of production efficiency and genetic gain in beef production systems. It has been reported to be at least twice as important, economically, as production traits under a conventional cow-calf operation (Melton, 1995). A delay in conception due to poor fertility prolongs the calving interval, and causes a shift in calving pattern, which can lead to culling. However, reproductive traits in cattle are difficult to measure, report and interpret. This is particularly true for pasture mating situations, where information on females in extremely limited. In these situations, the only information readily available is whether or not a cow produces a calf, and when she calves.