Mismark Case Study: Labrador Retriever

A gaggle of Labradors showing all three acceptable colors: black, chocolate, and yellow. Yellow can be in any shade of the red spectrum, from near-white to deep red. Chocolate can also vary. Image is from Flickr.com under a Creative Commons license.

Ebon is black with hints of red

Labradors, year after year recently, have been the AKC's most-registered breed. They are incredibly popular pet, and are also used for numerous working purposes, including hunting, tracking, and as service dogs. As those who read my blog regularly know, I myself have a Labrador, and he's a mismark to boot, though it's more subtle than most. The breed actually has a great number of mismarks that are seen:

• Too much white
• Anything more than a small amount on the chest isn't allowed
• Tan points
• In either black or chocolate dogs
• Brindle points
• In either black or chocolate dogs
• Improper pigmentation
• Where a yellow has a liver nose
• Silver (controversial)
• The blue dilution. Variations include "silver" (dilute chocolate, aka fawn/Isabella), "charcoal" (dilute black, aka blue), and "champagne" (yellow with a blue or fawn nose)

This yellow Labrador has a brown nose

Thanks to the restrictions provided by the standard,  Labs will usually be bred using color classes. Blacks are bred to chocolates and yellows are bred to blacks, but chocolates will rarely be bred to yellows. This is thanks to the fact that a brown nose on a yellow is not just frowned upon, but will actually disqualify a dog from showing. Usually, breeding chocolate to yellow is only done by those who breed their dogs for working ability rather than conformation. As such, brown-nosed yellows are most commonly seen in the more lightly built field-type Labradors and are rarely seen in the more heavily build show-type Labradors. As is so often the case, breeders of working lines could generally care less what the breed standard has to say as long as the dog can perform the required job.

This Labrador has too much white

One unacceptable appearance that constantly pops up in litters is too much white. Residual white happens all of the time in dogs that are genetically solid in color, which is why the mismark is present in every single breed out there that isn't supposed to have any white whatsoever. In Labradors, this is most often only a chest patch, but more extensive white can occur, spreading up the neck or appearing on the toes. The St. Johns water dog, a major ancestor of the Lab, had this amount of white as a standard occurrence. It seems odd to me that it is now considered unacceptable in the descendents. Interestingly enough, Bolo spots (white patches on the underside of the paws that are generally not visible when the dog is standing) are allowed.

This Labrador has tan points

Two mismarks that have been around for basically as long as the Labrador has been a breed are black and tan and black and brindle. Most Labs are dominant black (even chocolates and yellows) and dominant black can easily hide the recessives brindle and non-black/brindle that both allow the Agouti locus to show through. As such, two dogs carrying these recessives can easily produce black and tan or black and brindle puppies. Also, since the genes are recessive, carries aren't obvious until they throw a mismark. Even with selection, the colors simply aren't going to go away. In addition, there are other dogs like my Ebon with just a hint of red that may be very minimal black and tan and may go completely unnoticed, all depending on the amount of red that is distinguishable.

This Labrador is silver

Silver is a highly controversial color in the breed, thanks in part to the suspicion that the color was introduced through crossing with a Weimeraner. Whether it was that or a mutation: the color exists. Unlike a very large amount of people familiar with the breed, I don't really have much of an issue with silver existing in Labradors. However, I do disapprove of the breeding practices going into producing silver dogs, as well as the "charcoals" and "champagnes." It's inbreeding, pure and simple. It's a classic story: one or two dogs show up that are a desired color. Breeder wants to make more of that color and inbreeds like mad to produce a bunch of dogs that are the desired color. The blue dilution is recessive, and as such inbreeding is the only way to ensure the production of the color. This would be done through either only mating dogs that express the desired color or only matings dogs who are known to carry the color (and are thus related to that original population). Also, most silver breeders brag about their ability to produce litters that are guaranteed to have silvers and will charge heavy prices for the puppies of the desired silver color. There is usually no mention of the heavy inbreeding required to make the color possible. This is ridiculous, and does not bode well for dogs as all these people likely care about is profit.

Another practice I do not approve of when it comes to "silver" in Labradors is the mislabeling of colors. The AKC has advised breeders to register silver dogs as chocolate, when it fact the two colors are quite different. Silver, unlike chocolate, requires an additional gene for the color to be expressed. They also look quite different, with chocolate looking like, well, chocolate and silver looking like ash. The parent club doesn't support the practice of mislabeling, and neither do I. The two are different colors and should be identified as such. I hold the same position about all other breeds.

The Labrador retriever was originally meant to be a working dog: able to run and swim easily to go retrieve birds without breaking a feather. As such, color should not be a factor deciding what the breed should be. A dog with tan points is just as capable of retrieving a bird as a solid black one. If modern show breeds want to maintain that their dogs are still just as capable, why care about color? Why not stay true to what the breed once was? As I keep emphasizing, genetic diversity is of serious concern in purebred dogs. By disallowing certain colors, standards are only eliminating more and more diversity from the breed. Breeding for two separate types (show or "English" and field or "American") doesn't help either.