Determining accurate proportion of breed make up of UK sheep to enable combined breed genetic evaluations

Abstract

<p>The UK sheep industry has a stratified structure with specific breed types and crosses" i.e. hill breeds in the uplands and terminal breeds in the lowlands. Pollott (2012) reported that the amount of cross breeding is increasing indicating that about 56% of all ewes in the national UK flock were crossbred. This along with increased pressure from breeders who performance record has meant that development of a combined breed analysis is required for the national genetic evaluations. In order to provide a national combined breed evaluations accurate knowledge of the breed makeup is required to enable heterosis and recombination coefficients to be calculated and fitted in the model, resulting accurate EBVs of cross bred animals.</p>