At the request of buggis - Lab info.

[LoveMyLabs]

buggis and anyone else who asked about Labs (I lost track after 3 posts )- Labs come in 3 basic colors; black, yellow and chocolate. However, yellow can range from a fox red to a cream color (still called yellow) and chocolate can be light or dark. They can have a small white spot on the chest but it's not desirable if your showing them. White from old age or scarring is also o.k. Ummm...bridnling or more white than I already mentioned or dark chocolate with "tan" markings *kind of like a doberman* is not acceptable. I have seen black and tan purebred Labs though. It's a genetic throwback that is definitely not able to show but still registerable. Kinda cute and strange at the same time.

As for the "chunky" and skinny - Labmom pretty much nailed it. I've also been told that the show Labs *which are more of the English kind* are bigger, blockier head, thicker tail and the hunting Labs are thinner, have a little more tuck up, smaller feet, slightly thinner tail. Hunters can compete in conformation but may not get as many points depending on the other Labs showing. English, bigger Labs, can also hunt. Your optimal Lab is one that can hunt and show and is good at both. Good conformation, soft mouth for birds, can swim and work for long periods and listens very well. If you look at my pics you'll see that Gunner, my chocolate male, falls into the "English" category while Tira, my black female, falls into the "hunter" category. She actually does come from a long line of hunters and field champions and Gunner does have champion blood in his line as well.
Their son, Rebel, is a beautiful mix of both of them. He has his dads conformation and his moms hunting drive.

As for any "issues" with Labs and their colors...yellow Labs are more prone to skin conditions and sun burns. Chocolates are one of the harder colors to get, especially if the mom is black. Since black is the dominant color and most pups take after the mothers dominant genes 90% of the time you will throw black pups. They may look like both parents but will have their moms color. Chocolate Lab mom & dad, with chocolate pedigree will be way more likely to have chocolate pups. So will a yellow and chocolate. Blacks are more prone to heat exhaustion because black absorbs heat. They'll keep on going but may end up making themselves sick if you don't make them stop.

[LoveMyLabs]

Why is it that the yellow Labs' ears are always darker than their bodies, even when they have no shading on their bodies? And what causes the noses of yellow Labs to fade during winter months?

The answers to both these questions can be found by examining the tyrosinase enzymes responsible for producing melanin from tyrosine. Some forms of these enzymes are temperature-unstable mutants that only produce melanins under ideal temperature conditions. Some tyrosinase enzymes work more efficiently in colder temperatures. Extremities, like the ears, are usually a cooler temperature than other parts of the body and as a result, the tyrosinase is able to produce more pigment in this region.

Conversely, the tyrosinase enzyme responsible for producing the dark nose pigment in yellows is unstable at low temperatures. Under conditions of low temperature, the tyrosinase enzyme stops driving the chemical reaction, and tyrosine conversion to eumelanin in the skin will occur at a much slower rate. As a result, pigment will fade.

Though certain drugs may also produce pigment fading, this latter cause for reduction in pigment occurs because these drugs will bind to dopa (an early precursor to melanin in the reaction from tyrosine to melanin) and inhibit the further chemical reactions that result in melanin. This condition will also cause fading of pigment in the Lab.

[LoveMyLabs]

The silver coat color in Labradors has gained much attention recently and is a very controversial topic (see The Labrador Coat Color Controversy: Do Silver Labs Really Exist?). Reasons for the controversy stem from the lack of information available to trace the origins of this color in the breed as well as the fact that the AKC standard for the Labrador breed does not acknowledge silver as an acceptable color for a Lab. Some breed enthusiasts consider the silver coloration to be a sign of impurity of the bloodline, however, what geneticists have come to understand of recessive alleles is that they may be passed through many generations going undetected, such as the allele for tan points discussed above.

The range observed in silver coloration suggests that silver occurs through a modifying gene. There have been several possible outcomes observed for the silver Lab:

Black Lab + silver modifier = charcoal gray coat with a "sparkly"-like appearance. Nose: dark gray; Eyes: dark to light gray

Chocolate Lab + silver modifier = "mousy"-brown gray coat. Nose: same as coat; Eyes: yellow to gray-yellow

Yellow Lab + silver modifier = platinum to pale silver (yellow with gray casting). Ears: gray (instead of red-toned); Nose: dark to pale gray; Eyes: dark to pale gray.

There are several possible explanations for the silver coat color in Labs. The first explanation would attribute this rare color in the breed to the D locus. Recall that the alleles of the D locus modify the color determined by the B locus. Therefore, if a dog is homozygous or heterozygous for black at the B locus, presence of homozygous recessive "d" at the D locus would dilute the black pigment to appear blue. Alternatively, if a dog is homozygous for chocolate at the B locus, presence of homozygous recessive "d" at the D locus would dilute the chocolate pigment to appear silver. The absence of the corresponding "blue" phenotype in the breed, however, would seem to argue against this explanation.

Another explanation for silver coat color in Labs would attribute this color to the C locus. There is an allele mutant at the C locus that has been determined to cause silver coat color and blue eyes in dogs. The "cb" allele is believed to be a type of albinism. Since alleles at the C locus influence red pigment only, effects of the "cb" allele should only be observed in dogs homozygous "e" at the E locus. Therefore, a silver Lab would not only have to receive the yellow allele from both parents, but also receive the silver allele from both parents (which is recessive to the common "cch" allele). This allele would explain the silver-toned modification of coat observed in yellow Labs in the presence of the recessive "e" allele, however it would not explain the eumelanin modification in the black or chocolate-based silvers (since the C locus alleles primarily dilute phaeomelanin).

[LoveMyLabs]

...why some black Labs have only a few, not-easily-seen, white hairs on their chests while others have small white spots, it is best to first picture that all Labs are white--the condition of having no melanin production. The gene loci for color control both the color of the pigment as well as the distribution of melanocytes throughout the body of the Lab. Therefore, in a black Lab, although color is determined by alleles at the B locus, alleles at the A and E loci determine even distribution of the color over the entire surface of the coat. Labs that carry an allele other than "As" at the A locus, have a greater likelihood of expressing more white hairs than those Labs that do carry "As". Therefore, although all Labs should be homozygous for the S allele at the S gene locus, some may still express white hairs on the chest, bottom of the feet and under the arms and groin areas.

More info at this site:

http://labbies.com/genetics2.htm#FoxReds

[LabpupsUK]

Wow it's like being in a biology lesson, but really interesting. I didn't even know that silver labs existed.

[LoveMyLabs]

Technically they don't...anymore. Most have been bred out from the lines. Just like the black/tan and brindling. THose people that have "silver" Labs are trying to say they are a new, special color. Most of these people, at some point, mixed Weimeraner and then bred back to the Lab looks and kept the Weim color. Either way, it's not acceptable and is highly undesirable. Probably pretty neat looking, but if you're looking for more than a pet you sure won't be able to show with them. :) Personally I don't like the silver color, it's recessive for a reason. It's just not supposed to be there but genetics can be funny sometimes.

[LabMomHouston]

I think it's beautiful. I looked at a few breeders before I got Bella. But I would be concerned about where they came from....breeding with other dogs to get it. If it truly is recessive...only makes sense at some point that it comes back.

[LoveMyLabs]

Just a bump back to the top for those who haven't gotten to read and may want to.