What is what dogs have black roof of mouth?

The black roof of a dog's mouth is actually called the "hard palate." Some dogs have a dark or black hard palate due to increased pigmentation, which is a normal variation in many breeds. This pigmentation does not typically affect a dog's health, and is simply a cosmetic difference. However, a dog with a very dark or black hard palate may be more prone to developing oral cancers. It is important to regularly check your dog's mouth for any unusual growths or changes in the color of their hard palate, and to consult your veterinarian if you have any concerns.