One of the questions that came up in response to the posts on late greying was whether this could explain reports of early greying. More specifically, the question was whether foals could be born white grey.
There have been reports of dark-skinned white foals in the past. The original article that named and described silver dapple mentioned that one breeder found that crossing silver dapples with greys sometimes produced very pale foals.
“When by crosses of silver dapple with gray Shetlands, genes S [now designated Z] and G became associated, it was found that the graying of a black pigmented coat began earlier and might even be found in the first coat (at birth) and would thus be permanent throughout life, but colts … were more often born with incomplete whitening of the coat. As white becomes increasingly evident, they are designated gray-white, and as yearlings or two-year-olds they are entirely white except for the skin”
The breeder of the ponies, Fred Wilmot (pictured in the hat), had been breeding a line of grey ponies for many years at the time that article was written. Many were likely homozygous greys, which would have made them prone to rapid greying. It is also likely that Wilmot, who was selling matched teams, was selecting for this.
The fact that a black silver pony would already have a nearly white mane and tail and paler lower legs might also explain why some of the ponies appeared white so young. Some of the areas on greys that remain darker longer were already pale.
The Boulonnais have a similar situation. The mare pictured at the top of the post, Samer, is typical of the white grey color sought by breeders. Greying early and completely is desirable, so homozygous greys are common. Although silver has not been identified in the breed, most of the Boulonnais that are not grey are flaxen chestnuts. Like the young Shetlands in the silver dapple article, many Boulonnais foals are almost white at a young age. (These are foal inspection photos where individual horses are not named.)
MS Czarthan
This “white” Arabian from the 1960s is probably the best-known case of a horse said to have been born white grey. In the photo linked in the title, it would be easy to believe he was a dominant white. That comes from the angle that highlights the marking on his muzzle. In other photos, it is possible to see the dark skin on his face, though it appears that, like many greys, he lost pigment with age. He produced 30 registered foals, all of which were grey, so he likely was homozygous. He is an intriguing case because even the very pale Boulonnais foals linked above are not entirely white. They are also not newborn foals. It raises the question of whether he might have had an additional duplication of the segment responsible for greying. Remember that heterozygous greys have fewer copies, which is why they grey more slowly than homozygous greys, and late greys have fewer still. Could MS Czarthan have had more copies than a normal homozygous grey? If repeated segments make the area unstable, isn’t that the sort of “mistake” that could eventually happen?
Union des Tilleuls
(Elégant – Junie, Bambou)
I am aware of several chestnut Boulonnais mares with extensive white ticking or flank roaning. A small somatic greying spot can be seen if you look closely at this mare’s hindquarter. (This is a smaller version of the mark on the warmblood gelding Lorando B.)
Gavotte
(Lorenzo – Talita, L’As de Coeur)
This mare traces back to Cigale, the founder of the first formally identified dominant white variant (W1). Freibergers with this mutation are all-white or near-white. One of the quirks of this family, however, is that they often have more intense color when they are foals. This fades as the horse matures, leaving dark speckling on the skin or a mix of colored and white hairs. If you look closely at the pictures of Gavotte, her skin spots are visible.
Casanova
(Coka Petitcoeur – Rose du Maupas, Euro)
I plan to do an updated post about belton spotting shortly, but I want to share this horse. He has the type of broken face marking that seems common in breeds and lines where belton spotting is found. His mother has less pronounced spotting, but it is still noticeable.
Mother’s face marking (shown with his half-sister)
Sheriff KC
(Shinerspoeticjustice – Lightning April, Lightning Mark)