Reproductive and testicular characteristics of purebred and crossbred boars.

Purebred Hampshire, Duroc and crossbred (H x D, D x H) boars were studied to evaluate reproductive characteristics. One hundred seventeen boars were castrated at 7Y:! months of age to evaluate testicular weights and sperm numbers. Seventy-eight additional boars were studied to evaluate conception rate and embryo numbers when mated to Yorkshire gilts. Rate of gain and backfat probe were also available for these boars. The crossbred boars gained faster and had fewer days to 220 Ibs. than purebred boars. There was no difference in backfat probe between the crossbreds and purebreds. The Duroc boars gained faster but had a larger backfat probe than the Hampshires. The crossbred boars had 16% heavier testicles and 27.8% more testicular sperm than purebreds. Differences in conception rate and embryo number for gilts mated to purebred and crossbred boars were not significant, although the conception rate for gilts mated to crossbred boars was 8% higher and litters had .89 more embryos 30 days postbreeding than for gilts mated to purebred boars.