I was watching my previous video of the two new pups and realized that I couldn't see Beau against my black shirt in the subdued kitchen lighting. This is better.
Nose and skin pigmentation
Because Labrador colouration is controlled by multiple genes, it is possible for recessive genes to emerge some generations later and also there can sometimes be unexpected pigmentation effects to different parts of the body. Pigmentation effects appear in regard to yellow Labradors, and sometimes chocolate, and hence the majority of this section covers pigmentation within the yellow Labrador. The most common places where pigmentation is visible are the nose, lips, gums, feet, tail, and the rims of the eyes, which may be black, brown, light yellow-brown ("liver", caused by having two genes for chocolate),[19] or several other colours. A Labrador can carry genes for a different colour, for example a black Labrador can carry recessive chocolate and yellow genes, and a yellow Labrador can carry recessive genes for the other two colours. DNA testing can reveal some aspects of these. Less common pigmentations (other than pink) are a fault, not a disqualification, and hence such dogs are still permitted to be shown.[19] The intensity of black pigment on yellow Labs is controlled by a separate gene independent of the fur colouring.[19] Yellow Labradors usually have black noses, which may gradually turn pink with age (called "snow nose" or "winter nose"). This is due to a reduction in the enzyme tyrosinase which indirectly controls the production of melanin, a dark colouring. Tyrosinase is temperature dependent—hence light colouration can be seasonal, due to cold weather—and is less produced with increasing age two years old onwards. As a result, the nose colour of most yellow Labs becomes a somewhat pink shade as they grow older.[19]
A colouration known as "Dudley" is also possible. Dudleys are variously defined as yellow Labs which have unpigmented (pink) noses (LRC), yellow with liver/chocolate pigmentation (AKC), or "flesh coloured" in addition to having the same colour around the rims of the eye, rather than having black or dark brown pigmentation.[9][19] A yellow Labrador with brown or chocolate pigmentation, for example, a brown or chocolate nose, is not necessarily a Dudley, though according to the AKC's current standard it would be if it has chocolate rims around the eyes (or more accurately of the genotype eebb). Breed standards for Labradors considers a true Dudley to be a disqualifying feature in a conformation show Lab, such as one with a thoroughly pink nose or one lacking in any pigment along with flesh coloured rims around the eyes. True Dudleys are extremely rare.[19][20]
Breeding in order to correct pigmentation often lacks dependability. Because colour is determined by many genes, some of which are recessive, crossbreeding a pigmentation non-standard yellow Labrador to a black Labrador may not correct the matter or prevent future generations carrying the same recessive genes. For similar reasons, crossbreeding chocolate to yellow labs is also often avoided.
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Allie - My new foster Labby labvolunteer355 views
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