Characteristics of bulls with different genotypes of the OLR gene according to the productivity of female ancestors

Abstract

The aim of the research was to assess the origin of Black-and-White breed bulls with different genotypes according to the low-density lipoprotein receptor (OLR1) gene. The object of the study was one sample represented by 58 bulls-producers of black and motley breed belonging to JSC "Head breeding enterprise "Elite" of the Vysokogorsky district of the Republic of Tatarstan. A preliminary assessment of the breeding value of Black-and-White bulls with different genotypes for one of the lipid metabolism marker genes (low-density lipoprotein receptor - OLR1), which are mainly used in insemination of dairy cows bred in the Republic of Tatarstan, is presented. As a result of a molecular genetic study (PCR-RFLP), the animal population was selected by groups, taking into account the genotype at the loci of the OLR1 gene. Evaluation and selection based on indicators of milk productivity of mothers, mothers and fathers of bull mothers showed that producers with AA and AC genotypes of the low-density lipoprotein receptor gene had the greatest breeding significance in terms of milk yield and mass fraction of fat in the milk of female ancestors. Thus, the parental index of bulls with AA and AC genotypes of the OLR1 gene was 9071 kg, 3.90% and 9510 kg, 3.95% in terms of milk content and fat mass, which is slightly higher than in bulls with CC genotype by 817 kg and 1256 kg (P<0.05) of milk, 0.03-0.08% fat, respectively.