Optimizing sheep breeding programs with genomic selection

We discuss genomic selection as a way to provide information on breeding values for traits that are difficult to select for. A brief review of genomic prediction methods shows that currently in sheep, genomic prediction requires selection candidates to be genetically related to a reference population although it allows information of more distantly related individuals to contribute to selection accuracy. Subsequently we discuss genomic selection in a sheep breeding program context and discuss possible ways to optimize genotyping strategies in a breeding nucleus. Genotyping a proportion of pre-selected young males saves costs without compromising genetic gain, making genotyping cost effective even at a high testing cost. When only counting expressions of genetic gain in two tiers, the optimal proportion of males genotyped becomes lower and genotyping becomes prohibitive if testing costs are above $100 per head, unless breeding males can be used in the first year.