Inbreeding has increased among the endangered Konik and Hucul horse breeds over the last 35 years, a Polish study has shown.
The researchers based their finds on genetic data and pedigree information.
The Konik, which is Polish for “little horse”, is a Tarpan-like breed. Tarpans became extinct in the wild between 1875 and 1890, when the last known wild mare was accidentally killed in Russia during an attempt to capture it. The last captive Tarpan died in 1909 in a Russian zoo.
Several attempts were initiated in the 1920s to recreate a look-a-like tarpan through selective breeding of primitive horses in Eastern Poland said to have retained Tarpan DNA. The end result was the Konik horse.
The Hucul, or Carpathian pony, is a small horse breed originally from the Carpathian Mountains. It also retains many features of the Tarpan.
Jakub Cieslak and his colleagues evaluated the genetic diversity of each breed from 1980 to 2011, using genetic data on 3865 Konik and 1627 Hucul horses, as well as pedigree records from more than 7000 animals across both breeds.
“We observed an increasing trend of inbreeding since 1980,” the researchers reported in the journal, Archives Animal Breeding. However, it seemed to have been much more stable, oscillating around 10% in Konik horses and 5% in Hucul horses, since the beginning of the 2000s, when the breeds were included in conservation programmes in Poland.
The researchers said genetic diversity in the two breeds in Poland remained relatively high and conservation programmes should be continued to keep it at a “safe” level in the future.
In Poland, there are six different horse breeds managed under conservation programs: the Konik, Hucul, Silesian, Wielkopolska, Malopolska and Polish Heavy horse (Sztumski and Sokolski types).
The Konik and Hucul studbooks have been closed since the 1980s and currently no outside blood is accepted. Thus, monitoring of genetic diversity in the two breeds was important to avoid the potential negative effects of inbreeding.
The study team reported that average inbreeding in the Konik horses increased from 4.8% in 1980 to 8.6% in 2011. A similar but lower trend was also observed for the Hucul horses, where inbreeding increased from 1% in 1980 to 8% in 2011.
“Conservation programs of both breeds have similar goals – to keep genetic diversity at a safe level and to preserve phenotypic characteristics of primitive horses,” the study team wrote.
“Unfortunately, except for the recommendation to avoid mating of close relatives, conservation strategies seem to be unclear.
“We have observed an increased interest in the Polish primitive horse and Hucul breeding in Poland, which is, among other things, related to subsidisation of endangered breeds by the government.
“In our opinion, rather than a permanent increase of population size, more attention should be paid to control the genetic diversity parameters and population fitness of both breeds.”
They continued: “Overall, both sources of information (pedigree and genetic markers) indicate that genetic diversity of both breeds has declined over time, which is particularly more apparent in the case of the Polish primitive horse (Konik).
“Conservation programs of both breeds should be revised and clear strategies for future populations management should be proposed, including optimized mating strategies and successive control of genetic diversity parameters.”
Genetic diversity in Hucul and Polish primitive horse breeds .
M. Mackowski, S. Mucha, G. Cholewinski, and J. Cieslak.
Arch. Anim. Breed., 58, 23–31, 2015