Greying out?

[bellsandwhistles]

Posting here because of all the colour experts!

Can someone explain to me what controls the greying process? Why do some horses grey out so much faster than others?

This is my grey filly at 2.5 years old:
https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-ash3/77077_10151259075008389_1635267551_n.jpg

Any predictions on how long it will take her to fully grey out? I’ve heard it’s related to base coat colour but I don’t know what colour she was when she was born. She’s out of a grey mare with two grey parents, by a dark bay stallion with bay and chestnut parents.

[Simkie]

What controls the greying process is not understood at this time. There’s some suggestion that a homozygous grey horse will go grey faster than a heterozygous grey horse, but I’m not sure if that’s been proven, and that’s certainly not playing a role with your horse–your filly has to be heterozygous grey.

She is certainly VERY grey already and I would expect her to be completely greyed out within a year or two.

For comparison, here’s my grey filly at two (last spring):

http://s155.photobucket.com/user/simkie/media/Seven/2963750480048290005KvBLWa_fs_zps51b3d95d.jpg.html?sort=3&o=0

And if anything, she’s DARKER now. I regularly mistook her for the black horse in the field all winter.

[JB]

Yep, fairly well certain that GG grays faster than Gg, but it’s still a bit unknown.

[Royal_Monaco]

I had a Gg born palomino mare that was all white at 5 y.o.

My holsteiner mare also Gg is going on 6 y.o. and not as pale as yout horse:
https://www.facebook.com/caroline.lussier.33?ref=tn_tnmn#!/photo.php?fbid=10151269952861628&set=a.10150315434576628.384972.713231627&type=3&theater

[Simkie]

Content is unavailable, Royal Monaco

No one is saying that GG versus Gg is the only thing at play in how quickly a horse greys out–there are definitely other factors at work, and it does seem to be heritable. But those factors have not been identified.

It’s a good bet, though, that if the grey parent went quickly, the resulting offspring will also grey quickly. If the parent stayed dark for a long time, the foal probably will, too.

If anyone is curious, the filly I linked above is EeAAGg–red carrier, homozygous for agouti and heterozygus grey. Both her sire and dam are grey, and they both greyed pretty slowly.

[Ibehorsepoor]

[QUOTE=Simkie;6936733]
What controls the greying process is not understood at this time. There’s some suggestion that [B]a homozygous grey horse will go grey [/B]faster than a heterozygous grey horse, but I’m not sure if that’s been proven, and that’s certainly not playing a role with your horse–your filly has to be heterozygous grey.

I can tell you that this is definitely not the case. I have not tested my mare… however she was snow white… by the time she was three. I bred her to a grey… assuming that I would get a grey… nope… that tells me that neither grey I bred to was Homozygous. I bred a White grey to a steel grey… and I got a bay…

[Simkie]

[QUOTE=Ibehorsepoor!;6937063]
I can tell you that this is definitely not the case. I have not tested my mare… however she was snow white… by the time she was three. I bred her to a grey… assuming that I would get a grey… nope… that tells me that neither grey I bred to was Homozygous. I bred a White grey to a steel grey… and I got a bay…[/QUOTE]

And as I stated above, GG versus Gg is not the ONLY thing that controls how quickly a horse will grey out. Presumably there are several factors that control the time frame. Homozygousity is ONE of those factors. The others have not been identified.

Your horse may have gone grey faster if she’d been homozygous. No way to know.

[JB]

Exactly Simkie.

As the geneticists at UC Davis and they will tell you that GG is much more likely to gray out faster than Gg.

“much more likely” does not mean either 1) all the time, or 2) that Gg can’t also gray out quickly

[Donkaloosa]

There was a QH stud locally, Sonny Go Silver, some years back. He was snow white at a very young age — enough so that AQHA came and took a close look to be sure he was the same horse they’d registered. His babies were almost all born grey — regardless of what color the mare was. The few that were born with a real color shed out their baby coats and were grey. We assumed he was homozygous for grey, but something else must have factored in that made his babies grey out so young.

[springer]

[IMG]http://i929.photobucket.com/albums/ad140/bonneval/MycaPrairieFall201020102.jpg)
This is my “grey” mare at 3. She is no greyer now, and she just turned 5. I’m beginning to think she won’t grey out at all… lucky since she is a kind of cool color! Her parents were both grey.

[springer]

[IMG]http://i929.photobucket.com/albums/ad140/bonneval/MycaPrairieFall201020102.jpg)
This is my “grey” mare at 3. She is no greyer now, and she just turned 5. I’m beginning to think she won’t grey out at all… lucky since she is a kind of cool color! Her parents were both grey.

[bellsandwhistles]

[QUOTE=Simkie;6936733]
What controls the greying process is not understood at this time. There’s some suggestion that a homozygous grey horse will go grey faster than a heterozygous grey horse, but I’m not sure if that’s been proven, and that’s certainly not playing a role with your horse–your filly has to be heterozygous grey.

She is certainly VERY grey already and I would expect her to be completely greyed out within a year or two.

For comparison, here’s my grey filly at two (last spring):

http://s155.photobucket.com/user/simkie/media/Seven/2963750480048290005KvBLWa_fs_zps51b3d95d.jpg.html?sort=3&o=0

And if anything, she’s DARKER now. I regularly mistook her for the black horse in the field all winter.[/QUOTE]

Thank you Simkie! I wish we knew more about the genetic aspect, especially since my girl is definitely not GG. But very interesting nonetheless.

[Royal_Monaco]

I made the link public. Sorry about that.
As a 3 y.o.: https://www.facebook.com/photo.php?fbid=2292940203172&set=t.713231627&type=3&theater
As a 5 y.o.: https://www.facebook.com/photo.php?fbid=10151269952861628&set=pb.713231627.-2207520000.1366056728&type=3&theater
Here is my first mare at 8 y.o. ans she was the same color at 3: https://www.facebook.com/photo.php?fbid=445239576627&set=pb.713231627.-2207520000.1366056748&type=3&theater

[ElementFarm]

a history of gray in my mare (Gg by Riverman out of a bay Dutch [by Consul] dam)

at 2: http://www.facebook.com/karen.barbour.79/photos#!/photo.php?fbid=1921929371994&set=a.1830682530880.2107399.1354874626&type=3&theater

at 4: http://www.facebook.com/karen.barbour.79/photos#!/photo.php?fbid=1830683170896&set=a.1830682530880.2107399.1354874626&type=3&theater

at 8: http://www.facebook.com/karen.barbour.79/photos#!/photo.php?fbid=1830683530905&set=a.1830682530880.2107399.1354874626&type=3&theater

at 10: http://www.facebook.com/karen.barbour.79/photos#!/photo.php?fbid=2371665415114&set=a.1830682530880.2107399.1354874626&type=3&theater

last summer at 11: http://www.facebook.com/karen.barbour.79/photos#!/photo.php?fbid=4309937950716&set=a.3811317405514.2170697.1354874626&type=3&theater

now, at 12: http://www.facebook.com/media/set/?set=a.10200955309949040.1073741825.1354874626&type=3#!/photo.php?fbid=10200955311029067&set=a.10200955309949040.1073741825.1354874626&type=3&theater (this is not stolen. I purchased images on line and am waiting for the CD to be mailed)

This mare stayed quite dark fairly late, but then grayed the rest of the way quickly. She’s getting lighter every shedding, but so far is not very flea-bitten.

[Pancakes]

Anyone have any ideas about my guy? I don’t know his genotype, but he’s Dutch x TB. He’s about to turn 5 next month. This pic is from January. Anyone know why some start to grey in the face and flanks, and some other places? And if that is more likely to result in a dapple gray vs. a fleabitten? I’m hoping he stays dark for another year or two and that he starts to really develop star dapples in 2-3 years.

http://i29.photobucket.com/albums/c252/sass_a_frass/IMG_2055_zps8fd66af9-1_zps91f95823.jpg

http://i29.photobucket.com/albums/c252/sass_a_frass/248405d2-da46-4ac2-aab4-8b74a8e98c4a_zps5adc1f80.jpg

[JB]

Element, that’s actually fairly typical of a Gg graying process

Pancakes - fleabites are also genetic, with GG being more likely to develop them than others. I’ve seen a couple of GGs who were developing fleabites before they even finished graying out LOL As for the “why start here and not there”, there is SOME thought that it has to do with the vascularity of areas, which would explain why faces are usually among the first areas, but of course that’s not a given.

[mikali]

I just wanted to add that I find that the chestnuts often grey out the fastest.

Here is my guy at a week old and then again the fall of his 2yo year.

By comparison this is my Brown greying out: 5 months 3year 5year 7 year

This is the bay 10 days old and then 3 years