Genome-wide associative analysis of reproductive characteristics of a black-and-white Holstein cattle population in the conditions of the Northwestern region

In recent years, genomic assessment and the widespread introduction of modern biotechnological techniques have played a leading role in the implementation of breeding programs. For a long time, increasing milk productivity has been the main goal of breeding. This led to a significant decrease in reproduction in herds. The reproductive indicators of the uterine livestock of cattle can largely reduce the total profitability due to additional costs for manual, veterinary assistance and forced culling. Experienced groups are genotyped using the Bovinesnp50 V3 Beadchip chip are formed from the cows of black-and-white holsteinized breed. For the study, the main reproductive traits of cows were chosen: the age of the first insemination, the insemination indices in front of the first (a), the second (b), the third (c), fourth (d) lactation and the period between hotels. Analysis of associations throughout the genome was carried out using EMMAX software. 2 significant SNP and 5 conditionally significant were found. The CAMK2D candidate gene with the age at the first insemination, the TLN2 , WSCD2 , GAPT genes with the indicator, the number of insemination and genes WDR36 , TDRD10 with the inter -suffering period was identified. Based on the studies, we assume that with age there is a change in the genetic factors affecting animal fertility. The identified candidate genes affect the mechanisms of maturation of follicles, so the growth and development of embryos. The results can be used both for the selection of animals to improve reproduction indicators, and for the search for the fundamental foundations of the formation of fertility in cattle.