The aim of the study was to assess genetic variability in Slovak Pinzgau breed using pedigree analysis. The whole population consisted of 8311 individuals of that 2399 living animals (2373 cows and 26 sires) in the reference population. Pedigree completeness, parameters based on probability of identity by descent and gene origin was analysed. The mean inbreeding level in the reference population was low 0.57%, mean individual increase in inbreeding 0.25% and average relatedness 1.17%. A total 141 effective founders and 51 effective ancestors were found in the reference, resp. 257 effective founders and 103 effective ancestors in the whole population. The number of 21 effective ancestor explained 50% of diversity in the reference and 51 in the whole population. The results demonstrate need for better monitoring of population and can be implemented in preparation of the strategy for development of breed

Eva Hazuchová

Ivan Pavlík

Ondrej Kadlečík

Radovan Kasarda

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165Agriculturae Conspectus Scientifi cus | Vol. 76 (2011) No. 3 (165-168)ORIGINAL SCIENTIFIC PAPERSummaryTh e aim of the study was to assess genetic variability in Slovak Pinzgau breed using pedigree analysis. Th e whole population consisted of 8311 individuals of that 2399 living animals (2373 cows and 26 sires) in the reference population. Pedigree com-pleteness, parameters based on probability of identity by descent and gene origin was analysed. Th e mean inbreeding level in the reference population was low 0.57%, mean individual increase in inbreeding 0.25% and average relatedness 1.17%. A total 141 ef-fective founders and 51 eff ective ancestors were found in the reference, resp. 257 eff ec-tive founders and 103 eff ective ancestors in the whole population. Th e number of 21 eff ective ancestor explained 50% of diversity in the reference and 51 in the whole pop-ulation. Th e results demonstrate need for better monitoring of population and can be implemented in preparation of the strategy for development of breed.Key wordsPinzgau cattle, pedigree analysis, genetic diversity, inbreeding, relatedness, probability of gene originPedigree Analysis of Slovak Pinzgau Breed Ondrej KADLEČÍK ( )Radovan KASARDAIvan PAVLÍKEva HAZUCHOVÁ1 Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 94976 Nitra, Slovak Republic e-mail: ondrej.kadlecik@uniag.skReceived: May 13, 2011 | Accepted: July 6, 2011ACKNOWLEDGEMENTS Author would like to acknowledge Scientific Agency of Slovak Republic for financial support under project VEGA 1/0046/10.Agric. conspec. sci. Vol. 76 (2011) No. 3166 Ondrej KADLEČÍK, Radovan KASARDA, Ivan PAVLÍK, Eva HAZUCHOVÁIntroductionPinzgau cattle are bred in Slovak Republic for more than 150 years. It was imported from region of the Austrian Alps and populations’ breeding in Slovakia is from its constitution over connected (Pšenica, 1990). In 1970 re-building of purpose and breed type of cattle started. In this period several breeding bulls were imported, from which 24% were of Pinzgau origin (Pšenica and Tretinová, 1998). From 1970 to 1992 in pedigrees of Pinzgau cattle were introduced seven breeds, almost 50% Pinzgau bulls imported from Austria and 34% from Slovakia. Aft er 1990 considerable decrease of Pinzgau population size was observed in Slovakia. In several papers need for management of genetic resources (Toro et al., 2011) and evaluation of genetic diversity of species and breeds was emphasized. Evaluation was based on pedigree information (Boichard et al., 1997; Sölkner et al., 1998; Baumung and Sölkner, 2002; Gutiérrez et al., 2003). Th e aim of the publication was to assess the genetic variability of Slovak Pinzgau cattle in terms of parameters of the probability of identity by descent and gene origin. A number of genealogi-cal characteristics in the breed have been obtained.Material and methodsPedigree analysis was made in the whole dataset of 8311 in-dividuals of those 2399 living animals (2373 cows and 26 sires) in the reference population. Animals of reference population were born from 1988 to 2008 years. Dataset of cows included purebred animals with less than 6.25% share of foreign breeds as well as Pinzgau crossbreds with more than 6.25% of diff erent breeds. Breeding bulls, excluding one, were purebred. We tend to create dataset with maximum pedigree information, to reach good completeness of pedigrees. Whole dataset presented ani-mals of reference population with all known ancestors and base animals. Pedigree information was obtained from animal record-ing database of Breeding Services of Slovak republic, Bratislava. For data management soft ware SAS V9.2 was used. Individuals were sorted chronologically. For calculation of evaluation pa-rameters was used soft ware Endog V4.8 for monitoring of ge-netic variability in populations (Gutierréz and Goyache, 2005).Pedigree completeness was evaluated in relation to number of fully traced generations, maximum number of generations, equivalent number of generation (Maignel et al., 1996) and index of completness by MacCluer et al. (1996). Genetic diversity was evaluated in relation to two groups of parameters: 1) Parameters based on probability of identity by descent– Th e coeffi  cient of inbreeding (Fi), defi ned as probability, that two individuals receive identical alleles by descent (Gutiérrez et al., 2009).– Th e individual increase in inbreeding of each individual (ΔFi) calculated as diff erence of coeffi  cient of inbreeding of individual i and its parents (Kaerney et al., 2004).– Th e coeffi  cient of average relatedness of each individual (AR) as probability, that randomly selected allele from population belongs to particular animal (Gutiérrez et al., 2009). 2) Parameters based on probability of gene origin– Th e number of founders (f) – founder is animal with un-known genetic connections to other animals in pedigree except its own progeny (Lacy, 1989).– Th e eff ective number of founders, fe is defi ned as the number of equally contributing founders that will produce the same genetic diversity as assessed in the population (Boichard et al., 1997).– Th e eff ective number of ancestors is the minimum number of ancestors necessary to explain the genetic diversity in the reference population (Boichard et al., 1997)– Th e number of ancestors explaining 50% of genetic diversity.Results and discussionPedigree completeness was analysed in the whole dataset of 8311 individuals of those 7713 cows and 598 sires. Th e ref-erence population consisted of 2399 individuals of those 2373 were cows and 26 were sires. Pedigree completeness expressed by diff erent parameters has important infl uence on quality of inbreeding estimation and consequently evaluation of inbreed-ing depression. Th is was shown by Cassell et al. (2003), Weigel and Lin (2000). Th ey emphasized need to use more than two ancestor generations on commercial farms in calculations, as well as infl uence of pedigree completeness of sires on quality of pedigree information. Pedigree completeness in the reference population was ex-pressed by average value of maximum number of generations traced (5.0), the number of fully traced generation (2.05) and equivalent number of complete generation (3.16). Pedigree com-pleteness in the whole population was lower, maximum number of generations traced was 2.77, the number of fully traced gener-ations was 1.12 and equivalent number of complete generations 1.73. Share of known ancestors in the whole and the reference populations was expressed by index of completeness described by MacCluer et al. (1983) and results are shown in Graph 1. Pedigree completeness was lower than presented by Baumung and Sölkner (2002) and Sölkner et al. (1998) in Austrian Pinzgau cattle. Average pedigree completeness in reference fi le was 39.47% and in pedigree fi le was 21.64%.In Table 1 are presented results of estimated genetic varia-bility parameters. Average coeffi  cient of inbreeding in reference Figure 1. Pedigree completenessAgric. conspec. sci. Vol. 76 (2011) No. 3167Pedigree Analysis of Slovak Pinzgau Breedpopulation was 0.57%, increase in inbreeding per generation 0.25%, which was more than estimates in pedigree fi le. Average values of coeffi  cients of relatedness were in reference as well as in whole pedigree population higher than coeffi  cients of inbreed-ing. Th ese results showed that in the next generation could be expected, that number of inbred individuals will increase in spite eff ort of farmers to minimize mating of relative animals. In reference population were 11.37% of inbred individuals. Values of parameters of diversity were in group of inbred individuals signifi cantly higher, expressing lower diversity. Increase in in-breeding per generation point on breeding strategy, in particu-lar on selection of parental pairs, which results into higher resp. lower increase in inbreeding. Presented results point on eff ort of farmers to manage mating of animals to minimize mating of relatives. Lower values of parameters derived from common ancestor could be in relation with lower quality of pedigrees. Our results are comparable with values of relationship and in-breeding estimated in purebred and crossbreed population by Sölkner et al. (1998). High values of increase in inbreeding pre-sented Maignel et al. (1996) in France. Th e highest value was in Tarentaise (1.83%) breed, followed in Holstein (1.09%), Normande (1.07%) and Brown Swiss (0.90%). Reference population was derived from 2496 founder animals (Table 2). Eff ective number of founders and eff ective size of an-cestors were computed as described previously. Both parameters considered account for the chance of gene loss, which increases with the number of generations (Boichard et al., 1997). A total of 141 eff ective founders were found. A diff erence between number of founders and eff ective number of founders shows disbalance between founder contributions and excessive utilization of some animals as parents of the next generation. It also accounts for selection rate. Th e concept of the eff ective number of ancestors was accepted to account bottleneck. A bottleneck may be not only result of changes in size of population related to political, economical circumstances but can also occur due to a change in breeding goal (Druml et al., 2009). Th e eff ective number of ancestors 51 in reference and 103 in the whole populations com-pared with 25 in Abondance, 40 Normandale breeds (Boichard et al., 1997), 46.7 in Pinzgau (Sölkner et al., 1998) and 32.1 in Original Pinzgau, 14.2 in Tux-Zillertal, 29.0 in Carintian Blond (Baumung and Sölkner, 2002) gives higher values for Slovak Pinzgau breed. Th e calculation of fa gives possibility for estima-tion the most important gene contributions of ancestors. Table 3 shows the marginal proportions of fi ve the most contributing ancestors to the reference Slovak Pinzgau population. Sölkner et al. (1998) estimated in four breeds of cattle 16 – 55 ancestors explaining 50% of diversity, Bozzi et al. (2006) in three popula-tions 21-37 and in Slovak Pinzgau breed 21 ancestors in reference and 51 in the whole population. Eff ective number of founders/ eff ective number of ancestors’ ratio for the reference population of the Slovak Pinzgau was 2.4 resp. 2.1 for the whole pedigree population. Whereas fe/fa ratio was 2.19 in Limousine, 2.76 in Abondance and 3.3 in Normande (Boichard et al., 1997), in the whole Pinzgau population 1.41 (Sölkner et al., 1998) and Original Pinzgau 2.03 (Baumung and Sölkner, 2002). According to au-thors these results illustrate the narrower bottleneck in popula-Reference population Whole pedigree population Parameter Whole Inbreed animals Whole Inbreed animals x  0.57 5.02 0.22 5.70 Inbreeding coefficient  (Fi v %) s 0.27 6.54 1.78 7.09 x  1.17 1.38 0.61 1.36 Average relatedness (AR v %) s 0.51 0.45 0.63 0.48 x  0.25 2.21 0.11 2.81 Individual increase in inbreeding (ΔFi v %)  s 1.35 3.42 1.03 4.45 s=standard deviation  Parameter Reference population Whole population Number of founders (f) 2496 2501 Effective number of founders (fe) 141 257 Effective number of ancestors (fa) 51 103 Number of ancestors explaining 50% diversity 21 51 Ancestor Contributions (%) First  3.69 Second 3.48 Third 3.41 Fourth 3.34 Fifth 3.20 Table 1. Characteristics based on probability of identity by descentTable 2. Results of pedigree analysisTable 3. Th e most important ancestors contributing to the reference population from the whole pedigree populationtion due to fact that only limited number of sire was preferred for reproduction because of insemination used. ConclusionTh e analysis of Slovak Pinzgau population identifi es the spe-cifi c characteristics based on probability of identity by descent and gene origin. Level of inbreeding and its individual increase per generation are small in population but higher value of av-erage relatedness indicates possible increasing of inbreeding Agric. conspec. sci. Vol. 76 (2011) No. 3168 Ondrej KADLEČÍK, Radovan KASARDA, Ivan PAVLÍK, Eva HAZUCHOVÁintensity in the next generation. A better monitoring system is needed to increase population size without reduction of genetic diversity. 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Pedigree Analysis of Slovak Pinzgau Breed

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