The Newfoundland dog is a large working dog. They can be either black, brown, or white-and-black. However, in the Dominion of Newfoundland, before it became part of the confederation of Canada, only black and Landseer coloured dogs were considered to be proper members of the breed. The Newfoundland dog is a large working dog. They can be either black, brown, or white-and-black. However, in the Dominion of Newfoundland, before it became part of the confederation of Canada, only black and Landseer coloured dogs were considered to be proper members of the breed. They were originally bred and used as working dogs for fishermen in Newfoundland. Newfoundland dogs are known for their giant size, intelligence, tremendous strength, calm dispositions, and loyalty. The Newfoundland's extremely large bones give it mass, while its large musculature gives it the power it needs to take on rough ocean waves and powerful tides. The droopy lips and jowls make the dog drool, especially in high heat. There are several health problems associated with Newfoundlands.