The coat colour variation in the Przewalski's horse #2

In the previous post, I wrote that wild-caught Przewalski’s horses from the 19^th and early 20^th century displayed more colours than the modern population does after the genetic bottleneck in the middle of the 20^th century. These colours included the lack of pangare, lightly coloured legs, possibly non-dun (at least a rather dark colour instead of the light sandy colour that many individuals show), and very lightly coloured individuals. 

In the comments, two photos were linked that, however, undoubtedly show modern Przewalski’s horses lacking pangare. They are from the population at the Hustai National Park in Mongolia and can be seen here (photo #1) and here (photo #2). 

This shows that the non-pangare allele is definitely still present in the population, albeit its frequency seems to be greatly reduced. What is also interesting is how dark the colour of the non-pangare individual on photo #2 is. It is not quite as dark as the stallion Schalun from the early 20^th century which I mentioned in the previous post, but it is certainly darker than a Gotland pony, which has been found to carry both the non-dun1 and the domestic non-dun2 allele, but not the dun allele. I think it is not unlikely that this individual has the non-dun1 allele – when you compare it with the stallion on photo #1, which is definitely bay dun, you can see a clear difference to the individual on photo #2. Looking at the other individuals on photo #2, it seems that they have the same base colour on the neck and face, and the rest is diluted by pangare, which is very prominent on these individuals. So they might have the non-dun1 allele too. If that is really the case, the non-dun1 allele might be present in more modern individuals than only those in this herd, just not as apparent because the colour is diluted by pangare and non-pangare individuals are pretty rare in the modern population. But without a genetic test on the Dun locus in these individuals this is a speculation. 

This sparked my interest in the Hustai herd and I searched for images on google. As it happens, I even found an individual with lightly coloured legs (go here). I also found a rather pale individual from Hustai NP, but it was in its winter coat and the winter coat is always lighter in colour. 

 

This shows two things: some of the colour variants considered extinct by the sources I cited in the previous post are still present in the modern Przewalski’s horse population, and the Hustai herd seems to be rather variable in colour. I am curious on the background of this herd – since the Przewalski’s horse was killed off from the wild in the 20^th century, this herd must descend from individuals in captivity, and I wonder which location(s) the animals are from as they preserve all these colour variants that have become incredibly rare in the modern population.