Assessment of genetic diversity and phylogenetic relationships in Black Pied cattle in the Novosibirsk Region using microsatellite markers

There are currently over a thousand indigenous cattle breeds well adapted to local habitat conditions thanks to their long history of evolution and breeding. Identification of the genetic variations controlling the adaptation of local cattle breeds for their further introduction into the genome of highly productive global breeds is a matter of great relevance. Studying individual populations of the same breed with the use of microsatellite markers makes it possible to assess their genetic diversity, relationships, and breed improvement potential. Although the Black Pied breed is the most common dairy cattle breed in Russia, there are only a few studies on genetic diversity in local Black Pied populations in some Russian regions. The goal of the present study was to analyze the genetic diversity in Black Pied cattle populations in the Novosibirsk Region and compare them with other Russian populations; to identify significantly divergent populations with a view to preserving them under the programs aimed at maintaining the genetic diversity of the domestic Black Pied breed. DNA samples from 4788 animals of the Black Pied breed from six breeding enterprises in the Novosibirsk Region have been studied using 11 microsatellite markers. No significant differences in genetic variability parameters were found between individual populations. Private alleles have been identified in five out of six populations. Five populations have shown inbreeding coefficient values (FIS) below zero, which indicates heterozygosity excess. The population distribution test, principal component analysis, FST and DEST values, cluster analysis, and phylogenetic analysis have revealed two populations genetically distinct from the others. Essentially, the genetic diversity parameters of the six studied Black Pied cattle populations from the Novosibirsk Region show no significant differences from other Russian populations of the breed. Excess heterozygosity is observed in most breeding enterprises, which is a sign of a low inbreeding rate. To maintain the genetic diversity of the Russian Black Pied cattle, we recommend focusing on the two populations with significant genetic distinctions from the others.