Are there any with knowledge of "red" cattle that were registered prior to 1970 ( or even thereafter) as red, which are now known to actually have been dun?
The dun in America that descends from UK imports in the mid 1950's traces behind the Grinstead herd to Framfield lines, and looks as if it may have been in Radcliffe only a generation from foundation.
We have now found six animals registered as black from 2 parents registered as red. ( red x red = red unless one of those "red" is actually dun). There is more and more circumstantial data that dun was in the breed from foundation and registered as red.
Also seeking photos of Dexters prior to 1970 registered as red.
Also interested in animals with white markings. UK seems more stringent on white than US, I expect as there is more participation in showing and exhibition. Would like photos of animals with white as well.
Thanks !
Judy
USA
Dun prior to 1970's
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Kirk- Cascade Herd US
- Posts: 267
- Joined: Tue Aug 29, 2006 7:21 am
Re: Dun prior to 1970's
The thing we have to keep in mind with "dun" is that there are two different definitions of "dun" and also two different definitions of "red" .
Prior to DNA testing, both "Red" and "Dun" would have been based on the phenotype of the animal (how the animal looked). "Red" meant that the animal looked red. Dun meant that the animal looked brownish.
When DNA testing came along, the definitions of dun and red changed from being based on phenotype, to being based on genotype. The definitions of dun and red are now based entirely on genotype, and ignore the actual color of the animal.
Depending on genetics, some genetically dun animals can look very very red, and some genetically red animals can look very very brown.
The first breed standard published in 1900, said Dexters should be only black, or red. Since they didn't understand genetics, they meant black colored, or red colored (phenotype). They excluded the color "brown".
We now understand that black pigment fades to brown when both of an animal's TYRP1 genes are broken. The good working TYRP1 genes produce an enzyme that helps make black pigment look black.
Some black animals have tons of underlying red pigment, so if those black animals have two broken TYRP1 genes, then their black pigment will fade to brown, but their red pigment will shine through and they can look very very red. Prior to DNA testing, they would have simply been called "Red", but today we would ignore their red color, and we would call them "dun" based on genotype.
But some blacks have very little underlying red pigment, so if their black pigment fades to brown, they will look very brown and not red at all. These duns actually look dun.
Also, some E+ wild reds have lots and lots of black pigment. If these E+ wild-type animals have two broken TYRP1 genes, then all their black pigment will fade to brown, and they can look quite brown, even though they would be registered as "red" based on genotype.
TYRP1 genes regularly break in all animals including dogs, cats, sheep, horses, mice, rats, pigeons, etc.. The "dun" mutation is very very common. In breeds like Black Angus, they would simply cull it out. In breeds like Herefords, it can hide. Chocolate lab dogs are based on the broken TYRP1 gene. I've got pigeons and sheep with "Dun" genes (broken TYRP1 genes) on my farm.
It's very likely that Dexters have always had a few animals with broken TYRP1 genes.
Prior to DNA testing, both "Red" and "Dun" would have been based on the phenotype of the animal (how the animal looked). "Red" meant that the animal looked red. Dun meant that the animal looked brownish.
When DNA testing came along, the definitions of dun and red changed from being based on phenotype, to being based on genotype. The definitions of dun and red are now based entirely on genotype, and ignore the actual color of the animal.
Depending on genetics, some genetically dun animals can look very very red, and some genetically red animals can look very very brown.
The first breed standard published in 1900, said Dexters should be only black, or red. Since they didn't understand genetics, they meant black colored, or red colored (phenotype). They excluded the color "brown".
We now understand that black pigment fades to brown when both of an animal's TYRP1 genes are broken. The good working TYRP1 genes produce an enzyme that helps make black pigment look black.
Some black animals have tons of underlying red pigment, so if those black animals have two broken TYRP1 genes, then their black pigment will fade to brown, but their red pigment will shine through and they can look very very red. Prior to DNA testing, they would have simply been called "Red", but today we would ignore their red color, and we would call them "dun" based on genotype.
But some blacks have very little underlying red pigment, so if their black pigment fades to brown, they will look very brown and not red at all. These duns actually look dun.
Also, some E+ wild reds have lots and lots of black pigment. If these E+ wild-type animals have two broken TYRP1 genes, then all their black pigment will fade to brown, and they can look quite brown, even though they would be registered as "red" based on genotype.
TYRP1 genes regularly break in all animals including dogs, cats, sheep, horses, mice, rats, pigeons, etc.. The "dun" mutation is very very common. In breeds like Black Angus, they would simply cull it out. In breeds like Herefords, it can hide. Chocolate lab dogs are based on the broken TYRP1 gene. I've got pigeons and sheep with "Dun" genes (broken TYRP1 genes) on my farm.
It's very likely that Dexters have always had a few animals with broken TYRP1 genes.