Equine Coat Colors

Horses come in numerous different colors and the coat can display many patterns. The great diversity in color is because of the complex genetics responsible for hair pigment. However, there are a few basic colors that are most often seen. Black and brown types are among the most common. Variations or dilutions in the genes can cause other coat colors like palominos and roans. Unusual colors, including grullo, are rare but are still found in both wild and domesticated horses.

  1. What Causes Color?

    • Equine coat colors are determined by a complex genetic system. There are many series of genes that are associated with the color of the coat, and within each series is the potential for variation. Additionally, the hair colors of horses are so diverse because there is a gene for dilution, which causes several shades of a color. With the presence of both dominant and recessive genes, even the offspring of two like-colored horses may be colored differently from each parent.

    Bay

    • Bay is one of the most common equine coat colors. Bays have brown to reddish-brown bodies with black points. The points are the legs, mane and tail and the tips of the ears. Bays can also feature white markings on the face and on the legs beneath the knees.

    Black

    • True black horses have only B-series genes. This means they have two dominant black genes or a dominant black gene with a recessive one. They show no other color but black, with the possible exception of small white markings on the face or legs. Black horses may become faded in the summer because of sun exposure, making them look dull or brassy.

    Palomino

    • Horses with a palomino coat color are often golden yellow with cream or white manes and tails. There are many variations in this one color family, however, and the coat can range from deep gold to a very pale, almost beige-like color. The palomino gets its color in part from possessing two recessive red genes and is considered a diluted pigment.

    Roan

    • Roans are characterized by a solid color flecked with white hairs. This coat color can feature many white hairs or just a few over the body. There are three variations: the red roan, the blue roan and the bay roan. The red roan has a chestnut or sorrel coat, which are both shades of brown, mixed with white hairs. This combination makes horses look pink-tinted and because of this some red roans are called "strawberry." The blue roan has a black coat with white hairs, a combination that gives the horse a blue tone. Bay roans have bay coats with white hairs. Depending on how the white hairs intermingle with the brown hairs, they can look very similar to blue or red roans.

    Grullo

    • Grullo is a rare color that is caused by a pairing of diluted black genes with dun genes. The coat is a smoky or mousy color. This is not caused by a mixture of different-colored hairs that are found in roans. Each individual hair on a grullo is smoky or mouse-colored. Grullos also feature primitive markings, which include a dark dorsal stripe, face masking, dark withers and darker stripes on the legs.