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12) FUN WITH GENETICS: MY MARE IS A CHESTNUT GREYING ROANING FLEA-BITTEN VARNISH-SPOTTED LEOPARD MEDICINE-HAT TOVERO FLAXEN-MANED APPY WITH A DORSAL STRIPE AND ZEBRA LEGS. WHAT WILL HER FOAL LOOK LIKE?
Case #1: Kitty Cumming's greying chestnut appy mare.
I have a mare (9yrs.) that was born a bright chestnut with just a small white blanket (no spots) over her hips. When she began to shed her baby coat, there was a lot of white mixed in (a greying gene - G), but also, small copper spots appeared all over her body (today she looks nearly like a leopard with varnish marks). I'm assuming that - using a transparency effect - that she had not only a greying gene, but also a gene for leopard type spots over her body and that the spots really didn't appear, but were actually there the entire time, but weren't visible in the original chestnut base color. When the greying kicked in, replacing the base color, the spots then became visible. Since the greying didn't affect the spots - they must be governed by something the greying cannot effect. This mare's mother is a true red roan, but with a grey gene - she is still pretty roan, but lighter than at birth (she's 22 now). The sire of my mare is a leopard with strong leopard breeding (Prince Plaudit).
Well, the first thing you know (besides the fact that your mare is from racing lines, I believe Plaudit was a race horse of some merit) is that your mare has two ee genes otherwise she wouldn't have been born chestnut. She also carries an Appaloosa gene which allows the pattern to show through, but since she's greying out that pattern will eventually dissappear. I suspect she also has an R roaning gene because of how the spots stood out from the background for a while. She has at least two pattern genes: the appy pattern genes can be carried by solid horses but won't be expressed unless the horse is either Apl apl or a few spot appaloosa. There are numerous pattern genes (at least eight patterns are suspected) -- your mare carries a blanket pattern gene and a leopard spot gene. Also she has two flaxen genes ff indicated by the flaxen mane. So far we have your mare as: ee ff Gg Rr Apl apl and since I am not sure whether the pattern genes are dominant or recessive we'll give her at least one blanket gene and one leopard gene. (What a neat horse, you should write to Dr. Sponenberg and tell him about her.)
Now, I bred this mare last year. I bred her to a grey QH who has strong grey, black and what I call near black (even darker than a seal brown - they look black except upon very close examination of the muzzle and when the sunlight hits them just right) breeding. What I got, basically
dark almost black is still considered seal brown, it is genetically black with the pangare gene causing the light areas on muzzle and flank
>surprised me. I got a solid chestnut colt, with a chestnut mane and >tail with some blond highlights (mom has a very blond mane and tail). I >did expect more color at birth. I an convinced that this colt will grey >out. He does seem to be changing much slower than mom did though. As
I agree he will grey out, the grey gene causes greying at faster or slower rates based on other genes that can be selected for, but in this case I think that this is another indication that mom had roaning helping her to look grey faster.
he's losing his baby coat (he's 4 months now) there is some roaning around his blaze and some white hairs around the base of his mane (his mom was already making dramatic changes as she shed her baby coat and was the color she is now by the time she was 2 yrs.) I am sure he will gradually turn grey; whether he has any other body spots like mom, I'll
The description you have of him already having some white hairs on his face confirms the grey gene, generally greys will start greying at the face which will always be a little whiter than the rest of the body, whereas roaning generally is not as heavy or is non-existent on the face.
have to wait until he greys more. Mom is rebred to same grey stud for '92 - so we'll see what we get. Any thoughts on how this colt might turn or what I'll get next year? Also, this colt thus far has some future stallion potential. I'm curious as to what his color producing potential is and whether he'll produce any strong color other than greying. App/QH crosses are a big market and a good stallion will have to throw color even out of QH mares. What do you think?
From your description the stallion is G- (-means we don't what gene is paired with this one). What gene is paired with this can make a difference to you as a GG horse throws nothing but greys, not very useful for making colorful appaloosas. If the stallion is Gg on the other hand then there is a 1 in 4 chance that a mating between him and your mare won't be grey, 3 in 4 that they will be grey. This stallion definitely harbors an e chestnut gene, otherwise your colt wouldn't be chestnut. Since mom is Apl apl then the chances are the reason your colt hasn't shown spots or pattern is that he did not inherit one of the base apl appaloosa spotting genes from her, thus any pattern genes he has would remain hidden only to show up when he is mated to an Appaloosa mare, especially a few spot, but under those circumstances he could produce either a blanket or a leopard pattern depending upon what he inherited from mom, both patterns in one horse are possible. I believe from what you have said that he has one grey gene, not two, as horses who carry two GG genes tend to grey out very fast. If that is the case then there is a 50% chance that he can produce a non-grey if he is bred to a non-grey. He also carries the potential for a black, however that won't happen if he is bred to a chestnut as chestnut covers up black and bay. So far your colt is: a- ee Gg rr Apl Apl (meaning non-Appy) and probably carries one blanket and/or one leopard gene (he definitely does if these are recessive genes). He may or may not carry the pangare gene which the stallion may carry, we don't know nor will we unless your colt produces a seal brown.
If I were you I would breed this colt to nothing but Appy's with color who are non-grey that would up his chances of producing color. Also if you want black don't breed to a chestnut or chestnut Appy because he will definitely produce chestnut then (of course if you like chestnut that's great). P.S. he may also be able to produce bay when bred to a non-chestnut, black is tough to get. If he spots out later (please excuse my ignorance in this area and enlighten me if you have time) then he will be shown to carry one apl gene and can pass that along 50% of the time to both spotted and non-spotted horses.
The Sponenberg book is the only really good book on horse color genetics that I've ever found, it was published in 1971 and I borrowed a copy from the University of Arizona library and xeroxed almost half the book. It is called "Horse Color" by D. Phillip Sponenberg and Bonnie V. Beaver, I believe it was published by the Texas A & M University Press. I found a good section on Appaloosa color in another book that was being used as a text for a horse management class at Pima College a few years ago but I do not recall the author or name of the book (sorry). Good Luck to you and your horses. By the way your mare has a good chance of producing a non-greying appaloosa if bred to a non-grey stallion, 50% chance non-grey, 25% chance non-grey Appaloosa, but as you point out color is not everything, conformation is very important and should override color choices in many cases.
Tracy and everybody
Thanks for the response - I had once taken a genetics course in college