The Rat Terrier is an American vermin-killing breed which served its purpose as a general farm dog. The breed was common throughout America during the 1920s and 1930s; it is somewhat rare today as chemical pesticides and commercial farming have forced the decline of the breed. It was brought to the US by migrants from Britain, and it gained its popularity not only by helping on the farm, but through rat pit gambling, as well as hunting squirrels, hare, and other small game. The breed most likely developed from crosses of the English White Terrier, Manchester Terrier, Smooth Fox Terrier, Whippet, Beagle, Italian Greyhound, Miniature Pinscher, and Chihuahua. Smaller varieties, such as the Toy Fox Terrier, were split from the breed early on.
The Rat Terrier stands 13 to 18 inches tall and weighs 10 to 25 pounds. There are several smaller and larger varieties. The breed’s single coat comes in a wide range of patterns and colors. The most common color is black tricolor, but it can also be blue tricolor, brown tricolor, red, sable, or lemon. Ticking is typically visible through the white parts of the coat on the skin. The ears of the breed can be erect, tipped, or button. The tail is traditionally docked. The Rat Terrier is fine-boned.
The breed is cheerful and active, yet it can be calm and gentle as well. The breed has an acute “social sensitivity” which makes them easily trainable and sensitive to unexpected changes in its owner’s mood, noises, people, or activities. Proper socialization of the breed is critical. It needs plenty of mental stimulation from an early age. The breed also needs a good deal of activity and exercise.
The breed, due to its outcrosses, has more genetic diversity than many other breeds. This is what gives this breed its excellent health and keen intelligence. Some lines of the breed, however, do carry some genetic problems such as allergies, hip dysplasia, elbow dysplasia, luxating patella, malocclusions, bite problems, demodectic mange, seizures, and weight gain.