Dun is one of the base colors of the horse. Various factors contributing to the base color are passed along to successive generations in horses. The dun colors are dun to two entirely different genes, responsible for linebacked and non-linebacked duns.
The linebacked duns are widely distributed among the Spanish breeds, and they are very popular in breeds like the Criollo and Spanish Mustang. Linebacked duns are rare in the Peruvian and now extinct in the Andalusian. This dun color family is caused by a dominant gene, and once bred out, is gone for good. Horses can have two doses of the gene (homozygous) or one dose of the gene (heterozygous), but there is no difference in appearance. Only production records will indicate if linebacked duns will always produce linebacked duns. Except in rare instances, linebacked duns will have at least one linebacked parent. There are three major groups of linebacked duns - grullas, zebra duns, and red duns. Usually a shade of blue or beige, grullas have black legs, manes and tails, and usually a dark or black head. Since they are the linebacked version of the black horses, they occur in any breed with the same relative occurrence as blacks. Since black is rare in the Quarter Horse, grulla will also be rare. But in the Spanish breeds they are fairly common, as are black colors. Three types of grulla shading, representing the variety in coloring, are: lobo duns, slate grulla, and silver grulla. Lobo duns are dark and sooty with a black counter-shading to the body. Slate grullas are the bluer variety, and silver grullas are a silvery beige with a dark head. The linebacked version of the bay horse is a zebra dun. It is usually a more common linebacked dun, just as bays are usually more common than blacks in most breeds. The body color is usually a rich tan hue rather than being a clearer yellow color. Heads are usually darker than the body, but they are not as black or very dark as those of grullas, yet they still retain the black points. The linebacked version of chestnuts and sorrels are red duns, and they are the second most common of the linebacked duns. Red duns are often called claybank. The most pale red duns tend to have a reddish cast and pale shading on the stomach and between the legs, and are called apricot duns. Non-linebacked duns are caused by a gene called the cremello gene. One dose of it lightens colors to a middle range, but it has no effect on black. But two doses will lighten red and black to cream. This is the gene which causes those cream colored horses. Duns, Buckskins, Claybanks and Copper Duns
DunThis intense color is always found among horses in a wild state, but it is rarely round in horses bred to race and show, with the exception of the Quarter Horse. The Quarter Horse is derived from many native-bred horses. It is easily observed as having black points, black mane and tail, and often there are zebra-like stripes above its knee and hock. Also there is typically a dark stripe over the shoulder as well as the black stripe down the spine form mane to tail.There is a peculiarity in dun pigment that results in a dense arrangement in the tip end of the hair shaft. The layer of pigment is deposited on the bottom side of each hair, which tapers to a point, resulting in a solidly pigmented end. The dun color is uniform and the light refraction caused by the top side of the hairs causes most dun-colored horses to show a smutty appearance when in motion, rather than a sheen as in most other colors. Its hide is extremely durable, and little damage occurs from heat, sweat and pressure. Al shades of dun carry the tough hide and light refracting quality, and there is little or no serviceable difference between lighter and darker shades.
BuckskinClean of any smuttiness that may occur in other colors, the body color of buckskin is a self color. A two-colored buckskin has points which do not extend above the knees, and as the name ":buckskin" implies, the color should be that of tanned deerhide. The mane and tail are characteristically black, but the guard hairs which grow over the base of the mane and tail should be a clear, buckskin color. The feet are usually black and the coat color is a durable one. The horse's eyes will vary in color from amber to black, unless there is an unusual amount of white facial markings. Sometimes there is a black stripe down the spine form the mane to the root of the tail. While the pigment deposits are arranged similar to those in a dun, there is no concentration of pigment in the tip-end of each hair.
Copper DunA self color, this color has what might be a confusing pattern due to the fact that it is a double color. Markings on the lower legs, mane and tail, and the stripe down the spine have the chestnut cloud-like pattern. Neither chestnut nor dun, the overall body color, its overlapping pigment pattern within the hair shaft, and the general markings class it as a self color. This pigment pattern is the same as the intense color dun, but is less dense and because of its greater refraction and greater light absorption, it is considered a self color, rather than intense. Its hide is comparatively serviceable to that of standard chestnut and will withstand heat and light equally as well. The hide does tend to be less durable and resistant to pressure. Generally hooves are a dark amber color, but they can be black. When hooves are devoid of white markings, they are still serviceable.
ClaybankThe dilute of the copper dun, claybank has a slanted pattern of pigmentation in the hair shaft. The pattern is the same as that of the copper dun, except that there is less pigment in each pattern line, and there is a greater distance between lines allowing more light to enter. When exposed to really hard use, the hide does not show good durability. Also the lack of density within the hide causes it to be more sensitive to pressure and heat. Because it doesn't absorb much light, this pattern is not subject to sunburn. The claybank horse has amber-colored eyes, and the darker they are, the better. Its hooves are generally lightly-pigmented and borderline on brittleness.Look for an update on this article with genetic information soon. For more information on buckskins, visit:
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Published August 1997, December 1997 in NorthWest Breyer Horse Club newsletter. (em)
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© 1997-2007
NW Breyer Horse Club & Refiner of Gold Creations Equinealities in place since 1997, Section in place 2001, Updated 3/13/2007 |
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