Genetic variation of Bulgarian autochthonous sheep breeds using microsatellite markers

Abstract

The aim of the study is focused on the design of a conservation sheep breeding programme for the studied autochthonous breeds based on SSR markers genetic variation analysis applied. Seven local Bulgarian autochthonous sheep breeds (Breznishka, Sofiiska, Copper-Red Shumenska, Karakachanska, Local Karnobatska, Blackhead Plevenska and Starozagorska) were differentiated using six microsatellite (SSR) markers, aiming to assess the genetic variation within and between breeds. Among the total of 96 identified alleles, eighteen population specific ones were detected across the all studied genotypes of 338 individuals, except in the Blackhead Plevenska sheep. All examined breeds indicated high level of genetic diversity, with an average of 0.792. The genetic differentiation between the examined sheep breeds was not significant and the values of genetic distances were relatively low. The analysis of molecular variances (AMOVA) showed low variation between the examined breeds (5.51%) in comparison to within population variation (94.49%). The greatest distance (0.643) was found between the populations Local Karnobatska and Starozagorska, while the smallest one (0.108), between the Copper-Red Shumenska and Karakachanska. The genetic distances calculated by Neighbour-Joining method, produced a phylogenetic tree which separates the investigated sheep breeds into two main clusters: one including Blackhead Plevenska Breznishka and Local Karnobatska, and the other one consisting of the four remaining breeds - Copper-Red Shumenska, Karakachanska, Sofiiska and Starozagorska sheep. The Factorial Correspondence Analysis (FCA) showed isolation of Local Karnobatska sheep and Starozagorska and an admixture of the other populations.

Genetic diversity and structure of 2 indigenous sheep breeds (Kotel and Teteven) in Bulgaria using microsatellite markers

“…They have been phenotypically described and characterized, but these data do not give information about genetic variability within and between studied breeds which is important for their preservation. In Bulgaria, microsatellite markers were used for the first time in sheep with the aim to determine genetic relationship and genetic structure among 7 indigenous Bulgarian sheep breeds in order to facilitate and plan their sustainable development, utilization and conservation [1,18]. However, there is still lack of information about the genetic diversity and structure of the remaining 12 indigenous sheep breeds which is important for their effective preservation and conservation.…”

Characteristics of Autochthonous Breeds of Russia and Kazakhstan by Micronuclear Test

“…Мелкие микроядра указывают на снижение потенциальной жизнеспособности клеток. The micronucleus test is one of the methods for determining substances that exhibit genotoxic effects on the body (Hristova et al, 2017;McAllister et al, 2017;Luijten et al, 2018;Lu et al, 2018). Literary data indicate that the micronucleus test is not inferior, and sometimes even exceeds the chromosomal aberration tests in terms of informativeness and efficiency (Ilinskikh et al, 2011;Sabbioni et al, 2019).…”

Mitochondrial Diversity and Phylogenetic Relationship of Eight Native Bulgarian Sheep Breeds

“…To date, the majority of studies on the genetic diversity among native Bulgarian sheep have been performed only on autosomal short tandem repeat variations (STR, microsatellites) [39][40][41][42][43][44]. In this research, carried out in 2023, we evaluated for the first time the genetic diversity of eight native Bulgarian sheep breeds which are threatened with extinction, based on the sequence polymorphism of the mitochondrial control region (D-loop region).…”