Rat Terrier -- The all-purpose Rat Terrier can proudly claim to be made in the USA. Her popularity soared in the early twentieth century on American farms, where she hunted small game and killed rats and other vermin. She comes in miniature and standard sizes, and is a blend of Smooth Fox Terrier, Greyhound and Beagle, among other breeds. This dog is silly, fearless and vocal, and is known to be calmer than other terrier breeds. Needs constant exercise, games and training to prevent boredom.