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).