Inbred versus Non-Inbred Boars Used in Two Sire Herds on Wisconsin Farms

Abstract

Differences between the progeny (topcross) of inbred boars and the progeny (non-topcross) of non-inbred boars bred to non-inbred sows have been studied in 44 farm herds. Thirty-eight inbred boars representing several inbred lines were used in these intra-farm comparisons. Records were obtained on 1968 pigs from 314 litters sired by inbred boars and 2351 pigs from 366 litters sired by non-inbred boars. The variables studied in the comparisons of topcross and non-topcross litters were number of pigs farrowed, number weaned, number alive at 5 months of age and the percentage viability from birth to 154 days. Individual weaning weights, gains from weaning to 5 months of age and 5 month weights were studied on the topcross and non-topcross pigs. Data were also collected on the productivity of 200 topcross and 238 non-topcross gilts. Ovulation rates were recorded on topcross and non-topcross gilts representing one line. Pounds of feed per pound of gain and carcass information were collected from samples of topcross and non-topcross pigs farrowed and raised to weaning on farms and then brought to the University farm and fed from 72 days of age to a weight of 210 pounds. Copyright © . .