Towards Genomic Selection in Danish Warmblood Horses: Expected Impacts and Selective Genotyping Strategy

Abstract Text: The aim was to investigate the sensitivity of different selective genotyping strategies, and to approximate the impact of different genomic selection strategies on genetic gain in Danish Warmblood horses using selection index theory. An index for selective genotyping was presented based on reliabilities for multiple traits and average unrelatedness. This index was robust to varying weights on information sources considered. Compared to selective genotyping based on dressage alone, the index had negligible impact on prospects of genomic selection for dressage, while benefiting prospects for jumping. Compared with current practice (no genotypes; stepwise selection), the expected genetic gain in dressage from stallion selection was 4.3 times higher with a reference population of 5000 genotyped stallions and selection at 1 years of age. Benefits were smaller (1.6 times higher gain) with 500 stallions genotyped, partly because 3-year olds were selected to restrict inbreeding.

Keywords:

Genomic selection

Sport horses

Selective genotyping