A Genetic Study of Piglet Growth and Survival

The study analysed 954 Yorkshire sows from a research station in Sweden. The heritability for mean piglet weight at 3 weeks was 0.30 and the heritability for number dead up to 3 weeks was 0.09. Correlations showed that when the number of piglets born into a litter increased, it followed that each piglet weighed less at 3 weeks of age (genetic correlation -0.1). The higher the litter size at birth, the more piglets died, and if many piglets died in a litter, growth was low in the surviving piglets. The genetic correlation between mean birth weight and mean weight at 3 weeks was estimated to be 0.6.