Spring Brook Ranch is a seedstock yak producer, i.e., we provide high quality breeding stock to other yak breeders. We are committed to breeding the finest quality yak possible. Our herd is a deep gene pool containing some very fine specimens. This gene pool provides the foundation from which we breed the Spring Brook Type yak. All purebred lines, be it horse, dog, cat, cow or yak, were developed by methodical linebreeding. For instance, all purebred Hereford cattle must be able to trace their ancestry back to the foundation herd in Herefordshire, England. All Morgan horses trace back to a single stallion owned by Justin Morgan. This type of breeding program is well understood and a widely practiced animal husbandry tool.

At Spring Brook Ranch we focus on producing what we think is the ideal yak. We are not overly concerned with yak color as much as we are focused on producing a sound, robust individual. Yak color is immaterial if the yak bull is not a good breeder or the yak cow is not a good mother. Some breeds of dogs, for example, have been bred for show, concentrating only on appearance. The result are beautiful dogs that may lack intelligence or have congenital defects. There is a line of registered Quarter Horses from the stallion Impressive that have a genetic flaw that can cause them to simply fall over dead from cardiac problems. These are examples of mistakes we want to avoid when breeding yak. Yak evolved to survive in a very harsh climate; they are intelligent, hardy and beautiful. These are essential yak traits that we strive to retain in our selective breeding program.

Below are pictures of yak females displaying traits we look for. The obvious trait visible in these photos is wool, lots of it. Yak evolved in an extreme climate that requires a full and warm coat. We like to see good wool covering the entire body with a full and flowing skirt that should come down to snow level. We do not get skirts that reach the ground because our yak are raised in open range conditions where deep snow, creeks, briars and the like tend to clip the skirt hairs off. This is shown in the picture of the mature cow at the far right; her skirt and tail are trimmed evenly across at our average snow depth. The other two are younger animals that have not grown full skirts yet, but are off to a good start. We like to see full and flowing chaps on the front quarters with the protective guard hairs reaching to fetlock level. This protects the yak's chest and front legs when trudging through deep snow. The forelock should be pronounced, almost like bangs. This is like wearing a hat for the yak and protects their eyes from sun glare off the snow. When we get blizzards, the yak bed down and let the snow bury them.

Extreme wooly heifers
3 years old

Royal calf
7 months old

Black cow
7 years old

Spring Brook Type yaks are robust with a solid frame. They should have a refined look, not rangy or coarse. Their lines should be smooth and flowing. The top-line should blend well with the hump; too much hump gives a coarse look while too little hump makes them look like cattle. The hump, as in the American Bison, is there for a reason. The hump is formed by vertebra extensions and gives the yak immense leverage in lifting its head, which is very useful if you live where you have to plow snow with your head in order to find food. The front and rear quarters should be slightly rounded and well filled. Yak tend to have lighter hind quarters than beef cattle but not as sparse as bison. The legs are judged the same as cattle with too much bend or too straight a leg considered a fault. We consider too straight a leg to be a serious fault and will allow some degree of sickle hock and cow hock. This is especially so with breeding bulls. A bull with too straight a leg will be too inflexible to breed well. The head should be blocky and strong, as opposed to long and horsey.

Yak should show intelligence and curiosity, and not be flighty or aggressive toward humans. It is natural for yak to dislike aggressive dogs, since they evolved with wolves. Yak cows are very protective mothers and will be aggressive when they have small calves at side.

Like most serious purebred breeders we practice linebreeding. We practice a fairly conservative breeding plan; we do not breed parents with offspring or cross siblings. In simple terms, we alternate among three bloodlines. However, it is not simply a matter of alternating bulls; we are highly selective in which individuals become part of the "foundation herd" and thus part of the breeding program. By aggressive culling of inferior animals we concentrate desirable genes.