Analysis of polymorphisms in genes associated with milk productivity in red steppe and Caucasian brown cow breeds in two natural‐climate zones (mountains and plain) of Dagestan, Russia

Abstract

Aim . The unique gene pool of indigenous breeds in the Dagestan Caucasus is threatened by the increasingly widespread use of commercial breeds, which in turn risks narrowing the genetic base necessary to increase and maintain existing genetic diversity. For this reason, our research aimed to study the polymorphism of the PRL, PIT‐1, GH genes in red steppe and Caucasian brown cattle raised in the conditions of Dagestan. Methods . Genotyping of red steppe and Caucasian brown cattle was carried out using PCR‐RFLP methods. Using these methods, genetic analysis was carried out and polymorphism of the prolactin, somatotropin and pituitary‐specific transcription factor genes was studied. Results . As a result of the genotyping of an experimental group of red steppe cattle, it was found that the distribution of two alleles and three genotypes (PIT‐1A and PIT‐1B; PIT‐1AA, PIT‐1BB, PIT‐1AB) of the PIT‐1 gene has a specific character. The specificity of the allelic spectrum of the PRL gene is expressed in the high (0.84) frequency of occurrence of the PRLA allele and low (0.16) frequency of the PRLB allele. This is reflected in the presence of homo‐ and heterozygous genotypes with a frequency of occurrence of 73.0; 23.0; 4.0 %, respectively. Conclusion . Applied genetic approaches to improve the productive and breed qualities of livestock, which are modern and based on a more complete analysis of the genetic diversity and genotype of the studied populations, contribute to the conservation of zoned breeds. At the same time, intrapopulation variability and good adaptability should ensure the sustainable development of dairy cattle breeding in various climatic zones.