Assessing runs of homozygosity reveals production traits of Kazakh sheep breeds

Sheep breeding in Kazakhstan is one of the main local roles in animal husbandry. This article presents the results of a study of the genetic indicators of sheep breeds in Kazakhstan, in relation to their meat and wool productivity. Genetic analysis was carried out using the ROH (runs of homozygosity) method and candidate genes for various kinds of productivity traits were identified. The lowest mean genomic inbreeding coefficient values were observed in the Kazakh fine-wool breed and the Edilbay breed (FROH = 0.039 and FROH = 0.037). The highest values of inbreeding coefficient were in the Saryarka breed (FROH = 0.043), the Akzhaiyk breed (FROH = 0.044), and the Kazakh semi-coarse breed (FROH = 0.040). Since all these breeds possess the phenotypic traits for good meat constitution, the MSTN gene on the registered ROH islands has been identified and was found in all five breeds. In addition, genes affecting meat yield, adaptive traits, reproductive systems, immune systems, average daily weight gain, percentage of carcass fat, and third lumbar fat were observed within the recorded ROH islands using the Sheep QTL database. The results from the study of five breeds of sheep presented in the article are relevant (depending on the desired productivity traits) and have practical significance since only constitutionally strong animals, without exterior flaws and with high resistance to existing environmental factors, are able to produce higher yields and provide profitability to the sheep industry.