Selection of Fixed Effects in Sire Evaluation Models Using Akaike's Bayesian Information Criterion

Abstract

The authors proposed the method for selecting fixed effects in sire evaluation models using Akaike By calculating ABIC's for 15 alternative models, the model which included the combined fixed effect of {Calf born year}-{Slaughter house}-{Age class at slaughter} was selected as the best fit model for the five traits except Carcass price per weight, and the model which included the combined fixed effect of {Calf born year}-{Fatted prefecture}-{Age class at slaughter} was selected for Carcass price per weight.Slaughter house and Fatted prefecture were not included in one model at the same time, because these effects were strongly confounded.Sire born prefecture and Calf born prefecture were not employed in the best fit models.These results suggested that combined fixed effects were useful effects of the model in the Japanese Black sire evaluation.In the future, Fatting method which is not confounded with Slaughter house should be considered in stead of Fatted prefecture.