Gene polymorphism of the family of transcription factors and their influence on the milk productivity of the first heifers

Abstract

Purpose: this study investigated the polymorphism of transcription activators genes and their effects on milk production traits.Materials and methods. The first time in the Ural region, studies were carried out to determine the polymorphism of cattle in the STAT1 and STAT5A genes and the study of their associations with dairy productivity. Allele polymorphism was determined by the КASP method – Кompetitive Allele Specific PCR.Results. 92 cows were genotyped for the STAT1 gene locus, three genovariants were identified – STAT1СС (69,5 %), STAT1СТ (27,2 %) и STAT1ТТ (3,3 %). In the first lactation, the productivity of cows with the STAT1СС genotype was: milk yield 8379 kg, milk fat content 4.18 %, milk protein content 3.23 %. The individuals with STAT1СТ genotype had milk yield 8045 kg, MF 4.17 %, MP 3.23 %. And the individuals with genotype STAT1ТТ had milk yield 7855 kg, MF 4.16 %, MP 3.18 %. The advantage of cows with the STAT1CC genotype was 334-524 kg of milk compared to analogues from other groups. The genotypes of 90 cows were determined by the locus of the STAT5A gene. The STAT5ACT genotype is widespread among the studied livestock (51.1 %), the STAT5AСС genotype occurs with a frequency of 25.6 %, STAT5ATT genotype – with a frequency of 23.3 %. The productivity of cows with the STAT5ACC genotype was: milk yield of 8376 kg of milk, fat content of 4.19 %, protein content of 3.21%. The milk yield of the first heifers in the STAT5ATT and STAT5ACT groups is lower by 83–142 kg, the fat content is lower by 0.02–0.03 %. According to the results of the study, the STAT1 gene has an advantage for use as markers of high dairy productivity of Holstein cattle.