Grey

Grey is an ongoing process of depigmentation of the colored hairs. It is sometimes referred to as a pattern, which is incorrect. Grey is a modifier, which would be more accurate. Grey slowly removes the pigment from the base color, other modifiers (such as Mealy & Sooty) and dilution genes (such as Cream & Dun) that make up the original color of the horse. Grey has the unique ability to mask everything including any Pinto or Appaloosa patterns. No color is safe when Grey is present, as all horses that carry the Greying gene will end up a shade of grey or white. For this reason some breeders do not like to have mares or stallions in their breeding herd.

Grey is dominant, meaning, the horse must have at least one Grey parent to be Grey and if a horse has Grey it will be shown physically. Homozygous Greys do occur, the offspring of such horses will always go Grey.

Many think that Grey is the most dominant color or it is the strongest dominant gene. This is incorrect, Grey is not more dominant than any other dominant color or pattern gene - all dominant genes are equally dominant. Grey seems to be a "very strong" gene, only because it removes all physical affects of other color factors. This does not however mean that it removes the genes that causes colors and patterns. It also doesn't mean that a horse is going to be more likely to pass along the Grey gene than the dominant gene for Bay, Silver or Cream, etc.

At times, Grey is also incorrectly referred to as a color. While somewhat correct, it can be confusing because all Grey horses have a base pigment of either red or black and depending on what other genes are present all Grey horses were another color at birth. Figuring out the base color of a Grey horse can be very time consuming and some very surprising foal colors can be seen from Grey parents. Some think that all Grey horses start out being Black. This is a myth. Any colored or patterned horse can go Grey, from Black to Cremello.

Some Grey horses also undergo a progressive depigmentation of the skin. When in the early stages of depigmentation this causes a mottling that is similar to the mottling associated with the Appaloosa patterns.

There are several different stages to the greying process and each individual horse is different when it comes to the speed of this process. Some Arabians tend to go grey very quickly, while some Percherons usually grey at a more leisurely pace. The greying can even start in the womb so a horse can be born "Grey".

Foals that will grey out are usually born the "adult" version of the color or a very deep, rich color. For example: Bay foals that will not grey usually have light legs that shed out black with the first foal coat shedding. But a Bay foal that will grey usually has black legs at birth.

In most cases the first signs of greying are usually "goggles" around the eyes and on the face but sometimes the greying starts at the other end of the foal. White hairs may start showing up very early in the foals life, even a few days or weeks after birth.

Grey occurs in almost every breed, those that it does not occur in are those that have been selectively bred to a narrow or specific color range, such as the Friesian, Cleveland Bay, Suffolk Punch and Haflinger. In other breeds such as the Andalusian, Grey is very common. In some breeds Grey occurs, but is very rare, with only a few individuals existing in the world, such as the Morgan.