Interpretive Summary: Impact of including the cause of missing records on genetic evaluations for growth in commercial pigs 

By: Anne Kamiya, MS

Hot carcass weight (HCW) and birth weight (BW) are two heritable traits that are of high value in commercial pig breeding. These traits are valuable because they are needed to calculate accurate predictive breeding values. In this recent article published in the Journal of Animal Science, researchers evaluated predictive models and how adding data for livability (LIV) and loss of retained tag (RT) would impact heritability models in pigs. The authors report that nearly a third of pigs may lose their identification tags, which is significant. They hypothesized that including LIV and RT in predictive models would make these models more accurate. 

Pedigree information for approximately 2 million pigs included breeding values for HCW and BW. Two models were evaluated: model 1 (M1), which looked at BW, HCW, RT and LIV, and model 2 (M2), which only included HCW and BW. Heritability between M1 and M2 were comparable and there was no noted difference in accuracy by including or excluding RT and LIV. The authors did note as an aside that higher body weight was correlated with surviving to harvest. 

Overall, the results of this study suggest that including RT and LIV in genetic models do not provide any benefit over models that only include only BW and HCW. Although the authors’ hypothesis was not supported, this study did reinforce the accuracy of predictive models using only HCW and BW. More in depth studies looking at how the inclusion or exclusion of various traits in predictive models may benefit productivity and swine breeding are justified. 

The original article, Impact of including the cause of missing records on genetic evaluations for growth in commercial pigs, is viewable in the Journal of Animal Science.