Wow, do you have some of those sites?
I wouldn’t be suprised to find that there are modifiers that work in conjunction with the grey gene that determine the speed and style of greying. Especially dappled and flea bitten.
My horse is a chestnut based grey, quite dappled.
His dam was grey, and I don’t know for sure what her base color was, I think dark chestnut as both sire and dam were chestnut (dam greyed), but her mane was black even in old age.
She had several grey foals. Two were by a black stallion, and appear to both be black based. They were very dappled and very dark and slow to fade.
My horse was by a chestnut sire. Comparing photos of his (assumed) black based siblings at similar ages, he greyed much, faster than they did but does still retain nice dappling.
http://www.horsetesting.com/CCalculator1.asp
This was one of them-and without the base color you couldn’t do much. Granted now that I’ve looked more (I swear I looked a bunch but apparently just hit the right query now) there are more helpful searches.
This wasn’t the most complicated one I found but I don’t remember where that is.
Oh for sure there are different genetic components to whether a horse dapples or roans in the gray process. I THINK it’s theorized that if a gray lives long enough, he’ll eventually get flea bits, but certainly some horses do that pretty quickly after becoming white.
GG grays faster than Gg - I think that’s documented.
The Animal Genetics calculator is a good one. They are a company that does genetic testing as well.
However, I can see how one might interpret a result as looking like the gray possibilities as dependent on being a certain color 
For example, I chose a chestnut Gg Aa stallion and a black Ee non-gray mare. The results are:
Offspring Color Probability
25.00% -
Gray (Chestnut)
25.00% -
Chestnut
12.50% -
Gray (Black)
12.50% -
Gray (Bay)
12.50% -
Black
12.50% -
Bay
The biggest chance is a gray chestnut. However, that doesn’t mean you have a bigger chance of gray if it’s a chestnut, or chestnut if it’s gray, as I could see someone interpreting that to mean.
it means there is right off the bat a 50/50 shot at the base color being red, since ee x Ee gives you a 50/50 shot at a chestnut. But, there’s also a 50% that red-base can be gray, which puts it at 25% of a gray chestnut and 25% non-gray chestnut.
Of the other 50% nonchestnut, it’s split between black and bay, 25% each. But each of those also has a 50/50 shot at gray, so each of those is 12.5% gray on each of black and bay, and 12.5% non-gray on each of black and bay.
Does the amount of flea bites increase each year?
My horse has a few flea bites around his brow at age 9. His dam had none (never saw her in person, only photos) and was the same shade as he is now when she was 24. I’ve seen some who were so covered that it almost reversed the greying process.
Yes, flea bites tend to increase - they are a part of the continual graying process. Some start before the horse has even whited out LOL
This is our own personal experience. Our buckskin and palomino foals by our grey Welsh stallion took a few years to really start greying out. Our smoky blacks and black foal by the same stallion seem to stay dark for many years and just get a gradual greying of the head and tail. Ironically, three foals born bay (all out of bay mares) turned COMPLETELY light grey as weanlings when their first foal coats shed out.
Two observations:
It’s possible that rmh_rider was really talking about the number of greys in the Arabian breed making it more difficult to choose quality breeding stock that is not grey. She was just wording it badly?
Also, I too believe that chestnut greys go whiter quicker than bay/brown greys, and that black greys change the slowest. It would be interesting to know whether this is actually the case or not!
Nope, I really don’t think so:
[QUOTE=rmh_rider;6301816] When they do NOT want grey they usually breed to a stallion who has a very solid BAY background. And one who produces alot of BAY.
[/quote]
Also I would choose a bay with very little color pattern ie white on legs and face.
Also your mare being a TB is even better in the odds you will not get a grey. Grey is not very dominant in the TB breed. But still, go with a stallion who is known to cookie cutter the bay color no matter what he breeds.
[/QUOTE]
The color on my arab gelding was very strong on the sire side.
If I had another grey mare, I would breed to a horse who had zero or very little grey in the pedigree, or when bred to grey, didn’t produce it.
But like I said above, if I had one to breed I would choose a color and stallion who had a VERY strong color dominance, that is if you wanted the best chance to not have grey.
[QUOTE=Kerole;6304122]
Two observations:
It’s possible that rmh_rider was really talking about the number of greys in the Arabian breed making it more difficult to choose quality breeding stock that is not grey. She was just wording it badly?
Also, I too believe that chestnut greys go whiter quicker than bay/brown greys, and that black greys change the slowest. It would be interesting to know whether this is actually the case or not![/QUOTE]
I had a grey born black. He went from black, to charcoal, to a gorgeous black-grey with black mane and tail, with very black dapples spaced throughout his whole body, which progressively whitened each year. By the time he was 10, the dapples were mostly gone just mere shadows to what they were, and there were black specks that looked similar to the brown flea bits seen on other greys but his were black. He died when he was 11 so no idea what color he would have gone from there. I have no doubt had he lived to an older age, he would have turned pure white, but it was interesting to see what color he was going to shed out each spring.
His full brother was born a mahogany bay with white flecking. The flecking and greying out was much more noticeable when he was about 3 and he was looking almost strawberry roanish on his body by the time he was 6, but still kept his black mane and tail with white streaks starting to come in. I last saw him when he was 9 and he was more white with brown flecking and his mane/tail were streaking out white. His flecking hadn’t started to turn flea-bit yet. Their mother (TB) was grey-white (no flea bits) with black skin. Sire was bay (WB).
Both boys were very handsome in all their various shades.
Hmmm, yes, confronted with the evidence I must concede my idea was a daft one!
Oh, not daft at all! I’ve got the question out to 2 friends who have color geneticist connections, so if anyone will know, they will
[QUOTE=Wordplay1832;6301584]
Okay so I’m sure there are threads about this but I’ve never ventured to this part of the forum before.
I am thinking about breeding my grey thoroughbred mare. I don’t have a ton of experience in color genetics (and I know it can vary with which coat color she started out with, and I’m not 100% positive on that actually). But, as much as I love that my horse is grey, what are the odds of being able to breed for a baby that won’t grey out.
I’m sure there are certain stallion colors to breed to that are more dominant and may help over ride the grey, or be more predisposed, as well as their history and what colors their parents are etc.
Any input? Color is not the most important and if I end up with a gray offspring, that’s okay, but I would like to know my odds of avoiding it, in case I find a few stallions I really like and one may be better for that than another.[/QUOTE]
Check out this website it calculates the foals colour: http://www.animalgenetics.us/Equine/CCalculator1.asp
Dude. Thread is 2 years old.
Just noticed that this thread I started 2 years ago had been commented on and thought I’d give a little update! I did not breed my mare at that time, but she was actually bred late this summer and is expecting her first foal July 2015! She was bred to Gatsby, a homozygous black Oldenburg stallion. Very excited to see what I end up with!
Oh yay Gatsby! I have a G 3yo
[QUOTE=JB;7806441]
Oh yay Gatsby! I have a G 3yo :)[/QUOTE]
Awesome! I ride my trainer’s homebred Gatsby mare, she’s 6 this year and is just about to wrap up her first eventing season and has been spectacular! So I can’t wait to have a half sibling out of my mare too!
It’s easy to laugh, but it’s not as easy or as simple as some of you are making out. Why do you for example, have grey mares that produce a far higher incidence of either coloured/grey foals than statistically they should? Same with ratio of colts to fillies. 25 years ago concepts such as epigenetics would have been laughed at - but then we didn’t have a widely available internet 25 years ago (or internet bullies). Science is also moving on. I don’t think we can advise OP how to skew the odds when we know for example she has a 50:50 chance of a grey with a certain sire and dam, but nevertheless in time science may be able to tell us why mare x has had 10 colts and only 1 filly or why heterozygous grey mare y has produced 10 foals, all non grey.
Actually, it is that simple. A heterozygous grey has a 50-50 chance of passing grey with each breeding. It won’t produce exactly 50% grey offspring. And it matters if you are breeding a hetero grey to another grey, because then, yes, you will have more than a 50% chance to get grey. When you flip a coin 10 times, you might get heads nine times, and it doesn’t mean the game is rigged, it’s just luck in a very small sample size.
