Main Directions of Selection for Exterior Traits in Tatar Breed Horses

The study of the main breeding characteristics for the overall Tatar horse population and its four subpopulations revealed that the main deficiencies requiring correction during selection are mainly related to croup and neck parameters. The research was carried out on 200 horses of Tatar breed at LLC Breeding Company “Giniyatullin S.Sh.” in Tyulyachinskiy district, at “Garipov I.F.” peasant farm in Sabinskiy district, at “Nabiullin S.F.” peasant farm in Leninogorsk district and at “Bakirov F.R.” peasant farm in Alkeevskiy district of the Republic of Tatarstan in order to study the main selection characteristics. Results were obtained through visual and somatometric assessment, as well as variance analysis. Somatometric assessment of exterior revealed relatively small deviations from the model type for chest and metacarpal girth (1.1-1.6% in mares and 0.5-1.0% in stallions). Further negative changes in these measurements may lead to decreased endurance and adaptability to herd management, which is highly undesirable for the breed. These deficiencies in Tatar horses must be eliminated through targeted selection. The main breeding stock of Tatar breed has a typical harness conformation; only one subpopulation of horses has a conformation close to the riding type. Stallions currently used for breeding are distinguished by an increased bone index (13.8-14.1%), which is likely due to the herd management of horses. Since the heritability of controlled measurements and body conformation indices is very low and the maternal influence does not exceed 4.4%, selection of mares even of the desired type will not have a high selection effect. The preliminary positive results obtained in studying the relationship between the main measurements and body conformation indices and the allele frequency at individual microsatellite DNA loci suggest the successful use of this method in breeding for improved conformation traits.