Genomic Breeding Value Estimation in countries without large-scale genotyping: merging two training populations to increase genomic reliabilities.

For countries without large-scale genotyping, it is a challenge to implement an effective genomic evaluation system. Breeding company CRV has merged its bull training population with two such countries to build a training population of significance, and provide genomic software. Results show 6-20 times increase in training population adding the CRV bulls. The b-factors of the model(s) improve for most traits for both countries, with an exception for Israeli calving traits. Finally, the added reliability of genomic information, measured as equivalent daughter contributions, is on average four times bigger in the training populations including the CRV bulls, as compared to using only bulls genotyped by the country itself. Validation success may depend on the heritability of the trait, the estimated between-country correlation for the trait, the kinship between the two populations, as well as between the training population and the validation population, and -implicit in that between-country kinship- the past selection criteria as reflected in the similarities in the total merit indices over time.