We have talked about how genes determine the health of a collie, and now I want to talk about how they also determine a collie’s appearance. Many breeds of dogs have a variety of coat colors and types. Collies are known for their sweet expressions and beautiful coats. Collies have two varieties of coats, the rough and smooth coats. They have four recognized coat colors. The colors recognized by the AKC are sable and white, tricolor, blue merle, and white.
The sable and white coat can actually come in a variety of shades, from a light, buff color to a dark mahogany. The tricolor is predominantly black, with white and tan markings. The blue merle is a rich mixture of grays, blacks and white, which give it a bluish appearance. And lastly, there is the white collie, who isn’t actually a solid white color as the name implies. The white collie will have a predominantly white coat with either sable, tri or blue merle markings. The white color is not recognized in the European standard.
|Rough, mahogany sable - this would be a tri factored sable collie.|
|Sable headed white, photo courtesy of Darlene Kerr|
In Europe you will never see a rough and a smooth bred together, as they are viewed as separate breeds. In the U.S. rough and smooth collies are allowed to be bred together, but are judged separately at dog shows. In the U.S. the rough and smooth collies are considered to be two varieties of the same breed. Because we are allowed to breed these two varieties together, we have more dogs to choose from, and thus we have more genetic diversity.
|Rough and smooth collies|
A collie’s coat is determined by his or her genes. Because the gene for the rough coat is recessive , if you breed two roughs together the breeding will only produce roughs. If you breed a rough and a smooth together, you can have both rough and smooth puppies in the litter. The smooth puppies from such a breeding would be considered rough-factored. If you bred two rough-factored smooth collies together, you could end up with both rough and smooth puppies in litter, because smooths can carry the recessive rough gene. If you bred two pure-for-smooth collies together, you would end up with only smooth collies in the litter.
Tricolor smooth collie, photo by Jerrica Coady-Farrell
Coat color is also dependent on dominant and recessive genes. If you breed a tricolor with another tricolor, you will only have tricolor puppies in the litter. If you breed a sable and a tricolor, you will produce both tricolor puppies and sable puppies that are trifactored. Here is the color inheritance breakdown:
S - Sable
Dominant coat color, sable comes in a variety of colors, from straw to dark mahogany.
PS – pure sable
These collies carry no tricolor gene, and can only produce sable offspring.
tS – tri factored sable
sable collies carrying the tricolor gene along with the dominant sable gene. Most trifactored sables have a very dark mask and a darker sable coat.
Tri = tricolor
Recessive to sable, tricolors have black coats with white and tan markings.
M – merle
A dominant dilution gene which combined with sable or tri genes, produces merled collies.
BM – blue merle
Bluish gray coat with black splotching and white markings. Blue merles are the product of a dilution gene with the tricolor gene.
SM – sable merle
Sable and white collies with the merle gene, the sable merle comes in pure for sable and tri factored sable.
tSm – tri factored sable merle
These collies carry the tricolor gene alone with the sable and merle gene. Tri factored sable merles are usually a darker sable color than PSM.
PSM – pure sable merle
A light sable merle, with no tricolor gene.
W – white
These collies have a predominantly white body, with a colored head. They are the result of breeding two white parents or white factored parents. The color white is a recessive gene, and depending on the other gene received, the white collie may have tri, sable or blue merle markings.
Wf – white factored
Colored dogs with a lot of white on their neck, tail tip and white extending upward from their hind feet. When bred to another white factored or a white collie, they can produce white offspring.
WM – white merle
The white merle results from breeding two merled parents. These collies inherit the dominant dilution gene from both parents. They may be all white, or may have a few merle spots. They may be missing eyes, blind and/or deaf. They may also have severe impairment to their liver or kidneys. If bred to a tricolor, these collies will only produce blue merle offspring.
These are the offspring that may be produced by combining the the following sires and dams:
PS + PS = PS
PS + tri = tS
PS + tS = PS and tS
tS + tri = tS and tri
tS + tS = PS, tS, tri
Tri + tri = tri
Tri + BM = tri, BM
BM + BM = BM, tri, WM
BM + tS = BM, tS, tSM, tri
BM + PS = tSM, tS
WM + tri = BM
tSM + tri = BM, tS, tSM, tri
tSM + tS = BM, tSM, tri, tS, PSM, PS
tSm + PS = tS, tSM, PSM, PS
PSM + tri = tS, tSM
White + white = white
Wf + Wf = non-Wf, Wf, white
Wf BM + tri-headed white = blue-headed white, tri-headed white, Wf tri, Wf BM
White + non white = Wf
|Rough blue merle, photo courtesy of Jennifer Laik|