Association of FSHR gene polymorphism with fertility of Holstein cows

Relevance . The view of the mechanisms of hormonal regulation of the ovarian cycle of cows has allowed the development of a large number of synchronization programs. An active search is underway for biomarkers related to the fertility of cows, as well as to identify animals with a high ovarian response to the injection of exogenous gonadotropins. The aim of the work is to study the polymorphism of the FSHR gene and its association with reproduction indicators in black-and-white Holstein dairy cows. Results . Based on the results of genotyping cows (n = 128) using the FSHR gene, the frequency of occurrence of the CC genotype was determined at the level of 0.601, the CG genotype — 0.360, GG — 0.031. It was found that for productive insemination, animals with the CG genotype require fewer inseminations. At the same age, the frequency of insemination of heifers with the CG genotype was 1.43, with the CC genotype — 1.60. After the first calving, the animals with the CG genotype responded more actively to hormonal stimulation in the postpartum period. The interval from the first to fruitful insemination in cows with the CG genotype was 34.7 days, in cows with the CC genotype — 57.2 days (p < 0.05). The number of pregnant cows with the CG genotype re-inseminated after natural hunting was 2.1 times higher than the number of cows with the CC genotype (66.7% and 31.2%). It is assumed that exogenous hormone injection has a stimulating effect on the hypothalamus-pituitary-gonad system in cows with the CG genotype.