Animal breeding resolves problems of genetic evaluation - Slovak horses endanger

Animal breeding resolves problems of genetic evaluation (Vostrý et al., 2009), structure and assessment of genetic variability (Álvárez et a...

Animal breeding resolves problems of genetic evaluation (Vostrý et al., 2009), structure and assessment of genetic variability (Álvárez et al., 2010). Domestication of livestock species and a long history of migrations, selection, and adaptation have created an enormous variety of breeds of these animals (Groeneveld et al., 2010). Biodiversity is the variety of ecosystems, species, populations within species, and genetic diversity within species. Genetic variability has been defined as the variety of alleles and genotypes present in a population (Frankham et al., 2002). Variability of a gene pool over time reflects the change of genotype frequencies, 

which is closely connected with evolution. In animal breeding, genealogical information is important for genetic evaluation as well as for the evaluation of genetic variability (de Rochambeau et al., 2000). Results of the pedigree analysis provide an expected value of the increase in homozygosity and decrease in heterozygosity for the whole genome and can be considered as an appropriate strategy for monitoring populations for mating programs and for the management of genetic variability

 (Folch and Jordana, 1998; Valera et al., 2005; Mäki-Tanila et al., 2010). The pedigree analyses allow to assess inbreeding levels and population structuring (Gutiérrez et al., 2005). Results of such analyses can indicate the breeders of relatively small closed populations the size of genetic losses that could potentially appear. The aim of this study was to estimate genetic diversity in four Slovak horse breeds using parameters on probability of identity by descent and gene Pedigree analysis in four Slovak endangered horse breeds J. Pjontek1,2, O. Kadlečík1 , R. Kasarda1 , M. Horný3 1 Department of Genetic and Breeding Biology, Slovak University of Agriculture in Nitra, Slovakia 2 Institute of Animal Science, Prague-Uhříněves, Czech Republic 3 National Stud Farm Topoľčianky, Slovakia ABSTRACT: The aim of this study was to perform an analysis of genetic diversity in four endangered horse populations bred in Slovakia, describing parameters on the probability of identity by descent and gene origin. The analysed populations consisted of (reference populations in brackets) 656 (158) Hucul horses, 2052 (162) Lipizzan horses,

 1951 (171) Shagya Arabian horses, and 220 (42) Slovak Sport Ponies. The equivalent complete generations ranged from 4.93 for the Slovak Sport Pony to 10.25 for the Lipizzan horses. The average value of inbreeding ranged from 2.67% for the Slovak Sport Pony to 6.26% for the Hucul. The mean average relationship coefficients varied from 3.08% for the Shagya Arabian to 9.34% for the Hucul. Individual increases in inbreeding ranged from 0.43% for the Lipizzan to 1.06% for the Hucul, while the realized effective sizes were from 117.14 to 47.67 animals. The evaluated populations were derived from 80 to 499 founders. The effective number of founders ranged from 26 to 160, while the effective number of ancestors from 7 to 32. Keywords: coefficient of inbreeding; effective population size; effective number of founders; effective number of ancestors; pedigree analysis Supported by the Ministry of Education, Science, Research and Sport of the Slovak Republic (Project VEGA 1/0046/10 Strategy for sustainable development and utilization of genetic resources of farm and wild animals) and by the Ministry of Agriculture of the Czech Republic (Project No. MZE 0002701404).