Reporting of haplotypes with recessive effects on fertility


  • P M VanRaden
  • D J Null
  • K M Olson
  • J L Hutchison


genomics, fertility, embryo loss, genetic load


Genomic discovery of five haplotypes with recessive effects on fertility requires new automated tracking methods for QTL causing embryo loss in breeding programs. Most of the losses are early in gestation. Approximate locations of the five QTL were refined using crossovers detected within the pedigree. Of the top 100 available proven bulls for net merit, 15 Holsteins, 21 Jerseys, and 14 Brown Swiss are carriers of these haplotypes. Beginning with August genomic evaluations, carrier status is reported for all 127,588 genotyped animals in the North American database but is slightly less accurate for those with 2,900 markers or for imputed dams. Breeders should continue to use mating programs and index selection instead of direct selection against these haplotypes because their additive economic effects are small and are included in evaluated fertility traits.