Blue-black spots on tongues are very common in dogs: Over 30 breeds are known to have dogs with spotted tongues which are simply deposits of extra pigment, like birthmarks and freckles on people (dogs often have spots of dark pigment on their skin, too, which are often not seen because of the dogs’ coats). Only two breeds, however, have uniformly “black” tongues; the the Chinese Shar-Pei, and the Chow Chow whose tongue is one of the breed’s best known physical traits (a color that extends to its lips, as well, making it the only breed with the distinctive bluish appearance in its lips and oral cavity). As aside, giraffes, polar bears, and several breeds of cattle also have black tongues.  

The blue-black/purple tongue gene appears to be dominant, but Chow Chow puppies have pink tongues at birth. They darken to blue-black by 8-10 weeks of age, though some tongues don’t fill in completely, and these dogs may have small spots or splashes of pink. Senior citizen Chows, and Chows with the dilute coat colors of cinnamon and blue sometimes lose tongue pigment as they age and develop pink spots.

“Giggles” by Alicia VanNoy Call – dawgpainter
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