GENETIC STRUCTURE OF WARMBLOOD HORSES ON MOLECULAR-GENETIC LEVEL

The aim of this study was to evaluate the genetic structure and potential loss of diversity within three horse breeds: Lipizzan (42), Furioso (38), and Nonius (18) on molecular-genetic level. The genotyping data were obtained from in total 98 individuals presenting the genepool of analysed breeds in Slovakia. The values of gene diversity (0.72) as well as heterozygosity (0.89) showed the prevalence of heterozygotes within each population. The negative value of FIS index (-0.25) pointed, in particular, to good level of diversity and balanced proportion of homozygous and heterozygous animals in populations, i.e. HWE equilibrium. The Shannon s information index (I=1.41) confirmed sufficient level of variability mainly in order to maintain the current state of biodiversity for future generation. The genetic distances on intra- and inter-population level revealed clearly distribution of individuals into the three separate genetic clusters. The highest genetic similarity was found between Nonius and Furioso breeds (DA=0.16). However, the pairwise FST values and PCA analysis were not fully sensitive to detect the genetic differences among those breeds. We were able to detect only two genetic clusters, when Furioso and Nonius were linked together. This can be explained mainly by the use of English Thoroughbreds stallions and mares in building up process of both breeds. Considering that the results related to the state of diversity in presented breeds are correct, they can be used as basis for the further progress in breeding programs which is necessary to prevent the loss of heterozygosity and increase of inbreeding.