Jack Russell terriers, named after Rev. John "Jack" Russell, were developed in Devonshire, England, during the mid-to-late 19th century. With their compact but flexible bodies and natural instinct to hunt underground, they excelled as working terriers that could aid in the sport of fox hunting. Several types of Jack Russell terriers exist today, including show-quality and miniature versions.
Jack Russell Terriers
Standard Jack Russell terriers are fearless and energetic dogs that evolved from the original fox terrier. They have an average lifespan of up to 13 years and range in height from 10 to 15 inches with a weight between 13.2 to 17.6 pounds. Their trademark characteristics include colors that consist of mostly white with a combination of black and tan markings as well as three different types of coats: smooth (dense but smooth hair with an undercoat), broken (intermediate-length hair between smooth and rough) and rough (thick and dense hair with an undercoat). They are commonly confused with other types of Jack Russell terriers because they have the widest height range.
Parson Russell Terriers
Parson Russell terriers, the recognized show dogs of Jack Russell terriers, have longer heads and legs as well as larger chests compared to standard Jack Russells. Their maximum height is between 13 to 14 inches with a weight between 13 to 17 pounds. Their bodies include a relatively square outline with the characteristic Jack Russell colors as well as coats that range from smooth to broken since the breed standard does not recognise a Parson Russell terrier with a curly or rough coat. These energetic dogs are affectionate and require regular exercise and attention.
The short-legged Russell Terriers share many of the general features and characteristics with the Parson Russell Terrier, but are only between 10 and 12 inches in height at the shoulder. These strong, active dogs have flexible, rectangular-shaped bodies that are proportionally longer than the standard Jack Russell and Parson Russell terriers. With traditional Jack Russell colors, their coats may be either smooth, broken or rough. The breed is highly intelligent and confident with a natural instinct to hunt underground.
Miniature Jack Russell Terriers
Miniature Jack Russell terriers generally have the same overall features and characteristics as the standard Jack Russell terrier, but are proportionally smaller. They have either smooth or coarse coats and stand less than 10 inches in height at the shoulder with a weight of no more than 10 pounds. Before purchasing a Miniature Jack Russell terrier, it is important to verify that it has not been inbred since it can inherit genetic problems such as cataracts, deafness, allergic dermatitis or even Von Willebrand Disease, which is a blood-clot disease similar to hemophilia.