Data on age at first farrowing (IPP), total number of piglets born (NLN), number of piglets born alive (NLNV), and birth litter weight (PLV) were used to estimate genetic and phenotypic parameters of reproductive traits in Large White breed. Genetic and phenotypic variances and covariances were estimated by Restricted Maximum Likelihood method (REML). The model to analyze IPP included direct genetic effect, maternal effect and common litter effect, and the model to analyze NLN, NLNV and PLV included only direct genetic effect. Heritability estimates for direct additive genetic effects ranged from 0.17 to 0.34. Favorable genetic correlations between IPP and the other traits studied were observed. The low heritability estimates for most traits suggest that efficient selection strategies must be sought to increase genetic gain and that response for NLN may be obtained by indirect selection on NLNV.
swine; first farrowing; litter size; litter weight; genetic correlation; heritability
