COMPARISON OF DIFFERENT BREEDING PLANS FOR EVALUATING SIRES AND MATING SYSTEMS IN SWINE

Abstract

The effects of sires and mating systems on growth and carcass traits were investigated using within-litter (double mating), within-dam (sequential mating) and between-litter (random mating) comparisons. All three breeding plans were studied at a research station and, in addition, random matings were studied in the field. The experimental data consisted of 80 double mating litters (697 pigs), 302 sequential mating litters and 718 random mating litters whereas the field data comprised 622 random mating litters. Sire effects were important for postweaning growth and carcass merit whereas mating system differences were important only for postweaning growth. Based on estimates of the number of litters required to detect significant differences between sires or mating systems, double mating was the most efficient breeding plan. This advantage was most pronounced for the early growth traits.