Introduction
The dog is a canídeo mammal, perhaps the oldest domestic animal. Theories affirm that it appeared of the domesticação of the Asian cinereous wolf for the peoples of this continent has about 100.000 years. Throughout the centuries, through the domesticação, the human being carried through an artificial election of the dogs for aptitudes, physical characteristics or types of behaviors. The result was a great variety of more than 400 canine races, that currently are classified in different groups or categories.
The dog is a social animal that most of the time accepted its owner as the “head of matilha” and possesss some characteristics that become it of great utility it human being, possesss excellent olfato and hearing, is good hunter and running vigorous, it is omnivore, it is intelligent, relatively docile and obedient to the human being, with good capacity of learning. In this manner, the dog can be trained to execute great number of useful tasks to the man, as hunting dog; to shepherd flocks; dog of guard to watch properties or to protect people; to farejar diverse things; to rescue drowned or soterrados; to guide blind people; to pull small sleighs and as company dog. If it does not have knowledge of a so strong and lasting friendship between distinct species how much of the man-dog.