estimation and validation of indirect genetic effects for average daily gain in two purebred sire lines

Abstract Text: Accurate modeling of average daily gain (ADG) can contribute to a better response to selection for feed efficiency in pigs. Inclusion of indirect genetic effects (IGE) has been found to attribute to the heritable variance of this trait. A validation by predicting performance of young animals, has not been performed before. Genetic evaluations using purebred data (sire line S1 and S2) for ADG using an indirect genetic model were performed. Predicted breeding values by removing phenotypes of young animals (classical model vs IGE model) were correlated to corrected phenotypes. Models including IGE had a higher correlation (0.24 compared to 0.22) and the average accuracy of the breeding value was higher (0.52 compared to 0.48). These results illustrate the usefulness of implementation of IGE in pig breeding programs for ADG when sufficient phenotypes have been collected (in this study ~80,000).

Keywords: pig; indirect genetic effects; average daily gain