Data set of 161 mares and stallions in age of 3 and more years of Bulgarian Thoroughbred horse race were investigated by 12 microsatellite loci. The high levels of polymorphism were detected with microsatellite loci within the population. In horse breeding this technology has the potential to be of great use in monitoring levels of genetic variation within stocks as well as for parentage and relatedness purposes. The middle realization of the observed and possible genotypes, depending of established alleles per locus, is 72.3 % which are the implications of very high level of genetic diversity, the prerequisite of accuracy of parentage verification. Maintaining pedigree information on all individuals in the breeding program and using this information to arrange matings will ensure
only minimum increases in inbreeding every generation.
G. Barzev, E. Zhelyazkov, V. Barzeva, D. Hristova, Z. Sabev