Wild Bay

Wild bay has a similar phenotype to that of a normal bay, and it's allele (symbolized by A⁺) is found in the Agouti gene.

It is widely believed that the A⁺ allele is dominant to the other alleles (bay, black, and seal bay) in the Agouti gene. However, this has not been scientifically verified, and there have been reports of wild bay horses being produced by two bays. Another idea theorized by some is that the wild bay allele is part of a completely separate gene, not Agouti.

Regardless, it's pretty easy to pick out a wild bay from a normal bay. No, they don't all look mean, wild, and nasty. Instead, the black points on the legs only come up to the pastern (horse equivalent of an ankle) instead of the knee.

Here is a picture of a wild bay Arabian, and below that is a picture of a normal bay Mustang. Spot the difference?

Wild bay Arabian, image by Ealdgyth.

Normal bay American Mustang.

Confirmed Hypothesis

Just the other day, I got a chance to talk to a lady who attended college solely for learning about horse genetics. A couple points she made were foreign to me, but I'll take her word for it for unless I hear otherwise from a reputable source.

First of all, I learned that approximately half the population of horses have a roan gene, but it doesn't always appear if it isn't prominent enough (so it isn't a dominant gene, it's recessive). Which explains how one of my friends got a chestnut roan from two solid chestnuts.

Also concerning roan, it is possible to get the roan gene from the sabino gene. So now Cayenne's coloring is possible, yay!

I asked her one more question- how do you get a bay from a palomino and a chestnut? Okay, this is the one piece of information that seems iffy-ish to me, so I'll have to look into it further. Either way, she said that palomino's can indeed be a black base color, but you cannot see it because of the palomino dilution.

EDIT: Now, I would disagree. One copy of a cream gene on black does not produce a palomino-colored horse. Turns out that the "chestnut" is actually a silver bay.

So, that's that. If I remember what I had wanted to write about, or find that list of topics to write about, I'll try to do another blog post soon. :) And one that's a bit more interesting.

Understanding a Horse's Base Color

To understand horse color in general, you first must understand the three base colors and how they work. However, I won't touch much on the latter bit, as that is very complex and I don't want to confuse you (or myself, for that matter). So, to learn how each base color came to be, I'd suggest reading what D. P. Sponenberg's "Equine Color Genetics" has to say about it.

Anyway, to get back to the point; there are three base horse colors. There isn't any certain order, but I chose to arrange them as bay, chestnut, and black - as that is generally the order in how common each color is. Of course in some breeds, such as the Friesian and Suffolk Punch, they have been bred selectively for so long that it is rather difficult to get a chestnut Friesian, or a black Suffolk. And at least for the latter breed, if the horse is any color other than chestnut, it can't be registered anyway.

I imagine you all know what a bay, chestnut, and black horse looks like. Just in case you don't, here's a short description of each.

• Bay - A body color ranging from medium-dark brown, and oftentimes having a reddish tint to it. The points (tips of ears, mane, tail, and lower legs) are black. Sometimes a bay horse can have countershading and some people may think their horse is just a darker colored dun. Thankfully, there are more characteristics to a horse with a dun gene than just a dorsal stripe. There are also some subtypes to bay, and those are listed below.
• Sooty Bay - The sooty effect on any color simply means that the horse has a slightly darker body, with a few areas (head, flank) being the color underneath.
• Wild Bay - If you've ever seen pictures of a Przewalski's horse, then you probably have an idea what a wild bay is. A wild bay can be quite lighter than a normal bay horse, and the black on the legs doesn't always start till about the pastern, and even then it isn't always that black.
• Chestnut - This is simply a yellow-to-red-to-brown colored horse. They can have flaxen mane and tail as well, but that doesn't have anything to do with the genotype as far as we know.
• Liver chestnut - A liver chestnut may sometimes be confused for a bay, but in reality the genotype is exactly the same as a chestnut. The phenotype, however, is a lot darker. Liver chestnuts can still have flaxen mane and tail.
• Sorrel - In reality, sorrels are the same as chestnuts, but some people (and breed associations) just prefer to use different words. To get around this inconvenient issue, some horse geneticists will just use the term "red".
• Black - This is a completely black horse. When identifying a black horse though- one must be careful. Generally the easiest way to tell if a horse is really black is to search for the absence of red hairs near the eyes, flank, and pasterns. However, one also must keep in mind that some black horses will bleach out in summer (known as a summer black) while others will not (known as jet black).

Anyway, below are some charts to help you understand three common color genes in conjunction with the three base colors. The top layer is the base color, the second is the gene, and the third is the resulting phenotype. Also, for the champagne resulting colors it is not just a single word, but the word and then "champagne". For example, a gold champagne would be called a gold champagne, but not a "gold".

P.S. - If a horse has two copies of the cream gene, the affects will be different. Two copies of the cream gene on a bay or black results in a perlino, and two copies of the cream gene on a chestnut results in the lighter colored cremello.