Gray (horse) - Changes in The Color of Gray Horses

Changes in The Color of Gray Horses

A gray foal may be born any color. However, bay, chestnut, or black base colors are most often seen. As the horse matures, white hairs begin to replace the base or birth color. Usually white hairs are first seen by the muzzle, eyes and flanks, occasionally at birth, and usually by the age of one year. Over time, white hairs replace the birth color and the horse changes slowly to either a rose gray, salt and pepper (or iron gray), or dapple gray. As the horse ages, the coat continues to lighten to a pure white or fleabitten gray hair coat. Thus, the many variations of gray coloring in horses are intermediate steps that a young horse takes while graying out from a birth color to a hair coat that is completely "white".

Different breeds, and individuals within each breed, take differing amounts of time to gray out. Thus, graying cannot be used to approximate the age of a horse except in the broadest of terms: a very young horse will never have a white coat (unless it is a true white horse), while a horse in its teens usually is completely grayed out. One must also be careful not to confuse the small amount of gray hairs that may appear on some older horses in their late teens or twenties, which do not reflect the gray gene and never cause a complete graying of the horse.

This change in hair color can be confusing. Many new horse owners, not understanding the workings of the gray gene, are disappointed to discover that their dapple gray horse turns completely white a few years later. Other times, people traveling with gray horses who have a pure white hair coat have encountered problems with non-horse-oriented officials such as police officers or border guards who are unclear about a horse who has papers saying it is "gray" when the horse in front of them appears white.

To further complicate matters, the skin and eyes may be other colors if influenced by other factors such as white markings, certain white spotting patterns or dilution genes.