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10. ZEBRA STRIPES
Many horses carry "primitive marks", which can include a dorsal stripe, a withers stripe (like a donkey), and zebra stripes. Zebra stripes are transverse stripes on the legs, usually seen just above the knees and hocks of a dark-legged horse. Most wild equines carry these marks and it is probably a very ancient pattern. The marks are caused by the dun-dilution gene. Some of the western breeds show primitive marks quite often, such as the Quarter Horse and the Spanish Mustang. They are also seen in some European breeds such as the Fjord.
Jodie Gilmore writes:
My mare Mira is coal black with white markings in the winter, or in non-sunny areas of the country. When the sun shines on her, and when she sheds out, she has a black butt, and belly and legs, but her back and neck and shoulders are a dark buckskin color. Also, she gets "tiger stripes" on her ears, face, and sometimes on her shoulders. She has SOME white hairs on her barrel, but they don't seem to be multiplying at all. She also has an isolated black spot on the back of one of her white pasterns. So is she just a boring "black/bay", despite the tiger stripes? (I've never seen another horse with stripes on its ears.) Or would you call her a black/buckskin? Or maybe a black brindle?
Hmm, some black horses, those who are aa blacks as opposed to E-d jet blacks, get sunburned (i.e. they get fried) in the summer time and their black hair fades on the most sun-exposed areas to a reddish brown color. So this could be what is happening with her. The zebra stripes on her ears and shoulders are probably due to rubbing. She could be black/bay but I don't think so as you do not mention brown or tan areas on her flanks or muzzle. D dunning or P pangare genes seems to cause the color to be lighter in the winter than the summer so again it seems she is a black that gets sunburned.
Tracy and everybody