Dun refers to a certain pattern of markings. It is the effect of a
"dilution" gene that, when acting on a base colour (brown or black) modifies
the body colour to a lighter shade (gold or mouse-grey), while leaving the
mane, tail, legs and dorsal stripe darker, usually black or dark brown. In
addition, the horses with the "strongest dun factor" have a cross-stripe
over the withers, zebra stripes on the legs, and a spider-web of dark
markings on the forehead. They frequently have lighter hairs in forelock
mane and tail. A buckskin, on the other hand, doesn't have any stripes at
all, just the golden body coat with black points, mane and tail.
A dun may come in several shades of gold, ranging from a dark reddish gold
with dark red markings, to the typical yellow-gold with black more commonly
seen. A yellow dun has a light-gold body and darker gold markings. The
grulla is a beautiful mouse-grey with black markings. Because they are more
rare than the other colours (they have to be the result of the dilution gene
acting on a "true" black) grullas have been prized by breeders across the
country. There has been speculation as to whether the dun factor gene also
confers an extra dose of stamina and toughness. Every one that I have known
has been "tough as nails" occasionally strongly opinionated, with very
thick, hard hooves. Bob Morris may have some additional insight from his
experiences with Spanish Barbs.
The dun factor gene is found most commonly in the Mongolian Horse, the
Przevalskii horse seen in the Gobi desert, the Norwegian Fjord, and in the
Spanish Barb and its relatives, the Paso Fino, the Peruvian Paso, the
Criollo, Spanish Mustang, and the American Quarter Horse. In the UK, I have
seen several lovely Connemara ponies in the west of Ireland bearing these
markings, probably as a result of the commerce between Ireland and Spain
from about the 15th to 18th centuries.
Hope this helps! Please feel free to e-mail me privately to continue this
discussion, if you like.
Patty and The Roan
Rainbow Paso Fino Ranch
4331 Garden Spot Rd.
Clayton, WA 99110