Interpretive Summary: Genomic evaluation and genome-wide association studies for total number of teats in a combined American and Danish Yorkshire pig populations selected in China

By: Fang Fang, Jielin Li, Meng Guo, Quanshun Mei, Mei Yu, Huiming Liu, Andres Legarra, Tao Xiang

This study aimed at investigating joint genomic evaluation by combining data from multiple pig populations. Genomic evaluation is commonly applied in the pig industry to select the best animals to be the parents for the next generation. A bottleneck of genomic evaluation is that the selection accuracy is not high enough. To increase the selection accuracy, in theory, larger datasets are needed. In this article, multiple pig populations were considered together and we explored the feasibility and accuracy of genomic evaluation combining datasets from different populations. To realize the objective, total teat number (TTN), a trait that is equally recorded across different populations, was chosen. We first estimated the genetic correlation of TTN between American and Danish Yorkshire pig populations. Then to interpret why such genetic correlation was obtained, we employed the genome-wide association study to identify quantitative trait locus regions that are significantly associated with TTN and investigated the genetic architecture of TTN in different populations. Finally, we explored an optimal way of genomic prediction for TTN via three different genomic models and we concluded that when TTN across populations are regarded as different, but correlated, traits in a multitrait model, predictive abilities for both Yorkshire populations improve.

Read the full article in the Journal of Animal Science