There are dogs that can not bark

Basenji dog or African Nela - one of the oldest breeds of dogs. The history of the breed has about 5,000 years, the region of origin - central Africa. The uniqueness of the breed that its representatives do not bark, but emit a specific, peculiar only Basenji sounds like the rumble, but they can be heard only when the dog is excited. Also characteristic of the breed are the wrinkles on the forehead (in the reduction of the ears) and tightly curled tail. Dogs of this breed often wash paws like a cat. Basenji were withdrawn by means of a man, this breed has developed itself, by natural selection. As a result of this strong healthy dogs with good immunity, fearless and confident, and the appearance of the breed has not changed during the existence of the Basenji.

Source: ru.wikipedia.org

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