While rear dewclaws are fairly rare in dogs, the Newfoundland is one of several breeds born with them. The extra rear toenails may have given these large canines better traction and stability for working in the rough, snowy terrain and icy environments they were bred for.
Dewclaws are fifth toes complete with toenails on the insides of a dog’s paws. Situated higher on the leg than the other toes, they rarely if ever come into contact with the ground. Front dewclaws are attached to the dog’s paws with bone and muscle. The bone is typically absent in rear dewclaws, resulting in loosely attached digits that can easily get caught on something and torn from the dog’s leg.
Most dogs have front dewclaws. In addition to the Newfie, breeds with rear dewclaws include the Saint Bernard, Great Pyrenees and briard. The American Kennel Club breed standard for Newfoundlands specifies that rear dewclaws should be removed.
Breeders usually have this done when Newfie puppies are several days old, before the nerves become completely active. Older puppies and dogs must undergo a surgical procedure requiring general anesthesia. Veterinarians typically recommend dewclaw removal when the pet is spayed or neutered.
Inspect and trim dewclaws regularly. Unlike other toenails, they don’t wear down from walking and can curve and embed themselves in the tender pads.
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