Analysis of the genetic diversity of Ayrshire cattle in Russia. Message 2. Genome analysis based on data on the distribution of ROH patterns in Ayrshire cows

BACKGROUND: The analysis of ROH distribution is an important focus of genetic resource conservation programs of cattle. Characterization of ROH-islands allows to identify genetic factors affecting productivity traits of dairy cattle. AIM: was to analyze intra-breed genetic diversity and population structure of Ayrshire cattle, based on data on distribution of homozygosity patterns, as well as to identify loci associated with selection intensity and utility traits. MATERIALS AND METHODS: ROH distribution data were obtained using whole genome genotyping on Illumina BovineSNP50 (50K) DNA chips (Illumina Inc., USA). The object of the study was the DNA of Ayrshire cows (600 cows), which belonged to farms with different levels of selection and breeding work. RESULT: The results of our studies showed a generally similar level of inbredness of the analyzed Ayrshire cattle herds. The homogeneity of the population is confirmed by a large number of animals (72.83%) with FROH values between 0.10 and 0.20. Cluster analysis revealed consolidated groups of individuals, due to their ancestral origins. The discovered ROH-patterns included 268 genes, 32 of which were involved in regulation of the synthesis of protein and fat milk components. The results obtained may be used in breeding programs for Ayrshire cattle in Russia. CONCLUSIONS: The Russian population of Ayrshire cattle is distinguished by unique qualities in protein and fat milk composition and genome architecture, while maintaining genetic diversity and insignificant traces of Ayrshire cattle gene pool.