Association of GPX-1 gene polymorphism with cattle reproduction traits

Glutathione peroxidase-1 (GPX-1), has a strong antioxidant effect, enzymatically forming the body's antioxidant system, protecting cells from damage during oxidative reactions, reducing hydrogen peroxide to water and lipid hydroperoxide to alcohols, resulting in a decrease in negative effects on the body. The aim of the study was to research the reproductive traits of Holstein cattle with different genotypes of the glutathione peroxidase-1 gene. The study was conducted on 231 cows of the Mukhametshin Z.Z. Peasant Farm Enterprise (PFE) in Sabinsky district of the Republic of Tatarstan. Detection of polymorphism was carried out using the PCR-RFLP method in the Physiology, Biochemistry, Genetics and Animal Nutrition Department of the TatSRIA of FRC KSC RAS. Genotyping showed that the studied population of Holstein cattle is polymorphic in the GPX-1 gene. The frequency of occurrence was as follows: for alleles C – 0.513 and T – 0,487; for genotypes CC – 22.9, TC – 56.7 and TT – 20.3 %. Analysis of the associations of polymorphic variants of the GPX-1 gene with signs of reproductive traits showed that cows that are carriers of the CC genotype of the GPX-1 gene have the best fertile qualities, are characterized by greater live weight at the first insemination - 385.1 kg, and the shortest inter-calving and service periods – 373.4 and 102.3 days respectively, a high coefficient of reproductive capacity (0.98 units) and the Doha index (50.5 units), as well as the yield of live calves per 100 cows – 92.2 heads. The information obtained can be used to improve the reproductive indicators of cattle by including animals of the CC genotype of the GPX-1 gene in animal breeding programs when planning selection events.