Estimation of additive genetic, non-additive genetic, and permanent environmental sources of variation in preweaning traits in swine using the expectation-maximization algorithm for restricted maximum likelihood.

10188 growth records (performance up to weaning) of 283 Largewhite pigs were used to estimate various components of variance using a mixed linear model for the birth weight, litter size at birth, weaning weight, and litter size at weaning. Restricted maximum likelihood procedures were used. Object of the investigation were the respective additive genetic, non-additive genetic, and permanent environmental variation traits within the overall variation as well as the respective residual components. The results were tabulated and expressed specifically by way of the heritability and repeatability coefficients.