A 'Discovery'

I have been puzzling over the colour of some of Uno's foals, particularly the first filly out of Nehi Chinchee May, born in 2008. Uno being black pinto, and Chinchee palomino pinto, according to the Color Calculator there was a minimal chance of a solid black foal, so I assumed the resultant foal, although a diluted brownish colour, would eventually be black. However, she had a very definite dorsal stripe and 'primitive' barred leg markings. Checking out websites and the opinion of a fellow breeder conversant with colour genetics, the foal appeared to be a 'Grulla'', but the definition was that one parent had to be a dun, which of course was not the case. I therefore concluded the filly's brownish colour must be because she was a 'dilute' black and carrying the creme gene from her palomino pinto dam, but on DNA testing this was not so. The leg barring appeared to fade but the dorsal strip remained prominent.

As a result of my 2010 foals by 'Uno' all having dorsal stripes, and Chinchee once again producing a solid light brown/greyish coloured filly, I contacted the Animal Genetics Laboratory. I explained the colouring of the various mares, their sires and dams, and that none of them were dun, and 'Uno' was a black pinto. On further discussion regarding 'Uno's' parentage, his sire being the sorrel pinto Sierra Dawn Uno de Mayo and his dam a solid black, Dodsons Delta Blu, the geneticist suggested that the link was 'Uno's' dam, as black could be the carrier of a hidden dun gene, which she had passed on to 'Uno'. This would explain the dorsal stripes on his foals and the variety of unusual colours.

The Animal Genetics Laboratory are working on a test for the dun gene which will not be available until late summer, but will then enable them to distinguish whether 'Uno' is heterozygous, or homozygous for the gene. The test at present by their US laboratory can only give a positive or negative result as to if he carries the dun gene.

Now with Tiffany producing such an unusual coloured colt, which I find hard to describe, sort of milky chocolate/minky coloured with dorsal stripe, I just don't know what to expect any more !

Absolutely fascinating and opens up a whole new range of colours I wouldn't have expected.


©2010 Eileen Yaxley tel:+44(0)1404 841113 mob:+44(0)7786 564456