Friday, December 19, 2008

Duns

Dun is the "original" horse color, as in early horses were some variation of dun. A dun horse looks a lot like a buckskin, but it has markings that are referred to as "primitive markings", such as leg barring:



And dorsal stripes:



The original variation of dun was bay + dun + mealy. However, many more dun variations exist today.

A bay with the dun gene is a Zebra Dun:



A chestnut with the dun gene is a red dun:



A black with the dun gene is a grulla (pronounced grew-ya):



A palomino + dun is called a palomino dun or a dunalino. A buckskin + dun is called a dunskin.

An interesting fact about the dun color is that a horse cannot be a dun unless at least one of its parents was a dun also, unlike most other colors.

Thursday, December 18, 2008

Roans

Now, I'm going to talk about roans.

A roan is a horse who has the base color, such as bay or chestnut, mixed with white hairs. The head and lower legs are darker. Sometimes the mane & tail are also mixed with white, or "frosted".

A bay with roaning is called a Red Roan or a Bay Roan:



A chestnut with roaning is called a Strawberry Roan:



A black with roaning is called a Blue Roan.



Roaning can be found in all colors, but in light colors it can be hard to see. Here is a buckskin roan:



All roans carry at least one copy of the roan gene, which means that all of their foals will have at least half a chance of being roan. Roans are born the base color of their coat (bay, black, etc), but when they lose their baby fur, which is some time between 4 months and 1 year, the roaning shows. Sometimes a roan is confused with a horse that is greying out.


Wednesday, December 17, 2008

The Cream Dilution

Now that we know about the basic horse colors, I'm going to talk about the cream dilution.

A bay horse with one copy of the cream gene will be buckskin:


Notice that a buckskin horse looks alot like a dun horse, however, the are not the same. A dun horse will have a dorsal stripe and leg barring, and a buckskin will not. Also, the genes that cause duns and buckskins are not the same.

A bay horse with two copies of the cream gene will be perlino:


Perlinos are often confused with Albinos, but they are not the same.

A chestnut horse with one copy of the cream gene will be palomino:



And a chestnut horse with two copies will be cremello:



Notice how cremello looks like a very light shade of palomino instead of just white. Also notice the difference in the palomino's eyes and the cremello's eyes.

A black horse with one copy of the cream gene is very hard to tell apart from a normal black horse except by DNA testing or if it produces a cream dilution foal. Single dilute black horses are often called "Faded Blacks", "Smoky Blacks" or "Summer Blacks".

A black horse with two copies of the cream gene is a smoky cream:



Don't go anywhere, because next I'm going to talk about roans!

Tuesday, December 16, 2008

The Basic Horse Colors

I decided to do a series of posts on horse colors. This one will start with the basic horse colors, bay, black, chestnut, and grey.

All colors are either red based or black based. Bay and black horses are black based. Chestnut horses are red based. Grey horses can be either, because the grey masks another color, such as bay or chestnut. These horses are almost never born grey, the horse is born one of the other colors and then they "grey out" as they get older.

Grey horses are often confused with white horses, but see the black muzzle and the black around the eyes? A true albino has pink skin.

Grey horse (either base):



Here's a chestnut horse (red based):



Here's a true, or jet black horse (black based):



And this is a bay (black based):



One of the reasons that a bay turns out bay instead of black is because of a gene called Agouti. If Agouti is present in a horse's coat, it restricts the black to the legs and muzzle, so the horse is bay. If there is no Agouti, then there is nothing to restrict the black so it covers the entire horse.

Horses are either homozygous or heterozygous for any gene that they have. Homozygous means that a horse has a double copy of the gene, and will always pass on one copy of the gene to its foals. Heterozygous means that the horse has only one copy of the gene. For example, a horse that is DNA tested and shown to be e/e is homozygous for red, and will never produce a black based foal. But a horse that is DNA tested and shown to be E/E is homozygous for black and will never produce a red based foal. A horse that is tested to be E/e can produce a red based foal or a black based foal, because it has one copy of each gene. However, since black base is dominant and red base is recessive, a horse that is E/e will appear to be black based.

These are just the basic horse colors. You can add dilutions to them to get other colors, but we'll talk about that next time.

**NOTE: I got all of these pictures and all of the pictures I will be using in the rest of the horse color series off of Google.**