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bioRxiv · 10.1101/2020.02.19.956045

Analysis of structure of the population, kinship coeffcients and inbreeding trend depending on sex, type of breeding of Tatra Shepherd dogs

Abstract

The aim of the study was to analyse the structure of the population, kinship coefficients and inbreeding trend taking into account the sex, breeding system: champions (CH) and non-champions (nCH), breeding country: Poland (PL) and foreign country (Z) and the inbreeding degree of Tatra Shepherd dogs. Out of the currently registered 587 Tatra Shepherd dogs, 41.9% have been qualified for breeding. In the past decade, 1961 puppies were born, which corresponds to an average litter of 5.8 puppies. The breeds inbreeding rate amounted to 6.34%, and for a 4-generation population was 6.68%. The highest inbreeding rate was found in nCH and PL groups consisting of both male and female dogs. The inbreeding rate was significantly higher in 2005-2014 compared to the years 1994-2004. The limit value FX was exceeded for 25.65% of Shepherd dogs, and the critical value was exceeded for 11.52%. An increasing ancestor loss coefficient (AVK) was found, which may result in an increased number of inbred animals. In particular, it referred to female dogs in the nCH, PL, and F group, whereas a significant increase of AVK was observed in the group of male dogs from foreign kennels. The resulting COR values, respectively 55.58% for males and 55.44% for females, testify to insignificant inbreeding and suggest that breeders look for male inbreds. Studies have shown that there is no risk of inbred depression yet; however, the gene pool of the Tatra Shepherd dog breed has become noticeably restricted. In addition, leaving the stud book for the breed open must be considered due to an increase in the popularity of the breed, and thus an increase in mating.

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Niedziołka, R., Sweklej, E., Horoszewicz, E.. 2020-02-19. Analysis of structure of the population, kinship coeffcients and inbreeding trend depending on sex, type of breeding of Tatra Shepherd dogs. https://doi.org/10.1101/2020.02.19.956045

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