Influence of dominance effects on the estimation of direct genomic values in a crossbreeding design

Many of the commercial breeding programmes of beef cattle, sheep, pigs and poultry are using crossbreeding systems of two or more breeds. At present, mainly purebred information is used in genetic improvement programmes. Wei (1992) showed that inclusion of crossbreeding information will increase the overall selection response in the breeding programme. Genomic selection based on a dense single nucleotide polymorphisms (SNPs) panel has been found to substantially increase selection response (Solberg et al. 2008). The use of genomic selection in a crossbreeding scheme has been studied by Ibanẽz-Escriche et al. (2009). However, in their study only additive genetic effects were considered. But crossbreeding performances are expected to be influenced by dominance effects. Therefore, the main objective of this study was to assess the effect of ignoring dominance effects on the estimation of the direct genomic values (DGV) when utilising crossbred information.