Difference Between a Rat Terrier & Fox Terrier

Though the smooth fox terrier, wire fox terrier and rat terrier are separate breeds, they're alike in so many ways they could almost crash each others family reunions. Rat terriers have so much fox terrier in them that the breed used to be considered a "strain" of fox terrier, says the Rat Terrier Club of America. All three are intelligent, sociable, similar in size and temperament and easily trained. All retain a strong instinct to hunt and kill vermin, which makes them excellent dogs to have around anywhere rodents are a problem.

Until 1984, when they were designated separate breeds, the wire fox terrier was considered a variety of smooth fox terrier. The origins of both go back to 17th century Britain, where they were used by farmers to help control vermin and roust small game animals, including foxes, from their dens. Ancestry is a bit murky but according to the American Fox Terrier Club, smooth-coated black and tan terriers, bull terriers, greyhounds and beagles all contributed into the smooth terrier's genetic makeup. To produce the wire terrier, early breeders crossed smooth terriers with rough-coated black and tan terriers, eventually getting a dog with a dense, wiry coat with more white pigmentation, and a slightly different head shape, than the smooth terrier.

Since the annual Westminster Kennel Club competition began in 1907, fox terriers have scampered off with 18 best in show awards -- more than any other breed -- their most recent laurels in 2014. Oddly, these dogs are so underrepresented in the dog parks of America that many people may never have seen one. In the American Kennel Club's 2013 list ranking the popularity of 177 breeds, the wire fox terrier came 96th and the smooth fox terrier 116th. However, their small size -- the breed standard specifies no more than 15½ inches tall at the shoulder -- makes them ideal for apartment-dwellers. According to the AKC, fox terriers are playful, friendly and excellent around kids.

The Rat Terrier Club of America calls this cute dog a "rat" for short but fortunately, it was named not for appearance but function. However, the number of breeds that have gone into this made in the USA dog, especially in recent history, has presented an obstacle to breed standardization. In the early 20th century, when rat terriers were common farm dogs, different regions tinkered with bloodlines according to their own needs. Though they all carried heaping helpings of fox and many other terriers, some farmers crossed their dogs with whippets and Italian greyhounds to increase speed for rabbit-catching. Elsewhere, other farmers added beagle to improve tracking ability. The AKC didn't grant full breed recognition to the rat terrier until June 2013.

The diversity within the rat terrier's gene pool has given this breed some protection against hereditary conditions due to inbreeding, although hip and elbow dysplasia and allergies sometimes show up. If you're considering adoption, you have a choice between two sizes. A miniature rat terrier measures 10 to 13 inches tall at the shoulder, while the standard version measures from 13 to 18 inches. Weights range from 10 to 25 pounds. "Dogster" magazine advises that this energetic breed needs at least 30 minutes of exercise daily. The RTCA says that while the breed isn't particularly yappy, these dogs can be demanding, vocalizing their displeasure if they don't get the attention they feel they're owed from their humans.