IDENTIFICATION OF FERTILITY HAPLOTYPES IN THE BELARUSIAN POPULATION OF HOLSTEIN CATTLE

Abstract

Long-term artificial selection of highly productive breeding animals, latent carriers of genetic diseases, has led to the accumulation of recessive mutations in the cattle population. Since 2007, the Laboratory of Animal Genetics has been researching the fertility haplotypes of Holstein cattle (HHC, HHB, and HHD), and since 2016, the Laboratory has started additional research by other haplotypes (HH0, HH1, HH3, HH4, HH5, HCD) that affect reproductive traits and are associated with embryonic and early postembryonic death of calves. Earlier developed methods allowed us to identify mutations in the FANCI, APAF1, SMC2, GART, TFB1M, SLC35A3, ITGB2, APOB, and UMPS genes associated with these haplotypes. Monitoring cattle populations in Belarus (n = 4101 heads) made it possible to reveal the frequency of occurrence of the hidden carriers of mutant alleles of the HH0 haplotype amounting to 3.42%, HH1 — 2.82%, HH3 — 3.75%, HH4 — 0.59%, HCD — 2.35%, HH5 — 2.2%, HHC — 2.56%, HHB — 0.65%, and HHD — 0%. We believe that further DNA diagnostics of foreign and domestic breeding will allow diminishing the spread of genetic defects that degrade the reproductive qualities of cattle.