American Bobtail

The American Bobtail is a relatively new and uncommon breed of cat which has appeared since the late 1960's. It is most notable for its stubby "bobbed" tail about one-third to one-half the length of a normal cat's tail. This is the result of a  cat body type genetic mutation affecting the tail development, similar to that of a Manx. The cat is not related to the Japanese Bobtail despite the similar name and physical type — the breeding programs are entirely unrelated and the gene causing the mutation is different because the gene causing the American Bobtail's tail is dominant, whereas the Japanese Bobtail tail gene is recessive.
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Brown mackerel tabby longhaired American Bobtail.
Photo: Tetsu Yamazaki

Overview
American Bobtails are intelligent, good-natured, friendly cats, although they are somewhat shy with strangers. Many Bobtails play fetch and come when called.
Appearance
The American Bobtail is a stocky, muscular, medium to large cat, with hindlegs that are longer than the forelegs. The head is broad, with large, almond-shaped eyes and moderately large ears set low on the head. The unique tail, which reaches about halfway down to the hock (the "ankle" of the hindleg), is probably the result of a genetic mutation similar to that responsible for the lack of a tail in the Manx cat. Bobtails come in both long- and shorthaired varieties; the coat of the shorthair is actually medium in length. The coat is best described as shaggy, with a dense undercoat. All colors and patterns are recognized.
Special Grooming Needs
Bobtails should be groomed at least twice a week to remove loose fur.
Origins
In the 1960s, an Iowa family mated their Siamese with an orphaned male tabby that had a short, upraised tail. Some of the kittens had their mother's long tail, while others had their father's short tail. One of the short-tailed cats mated with a long-tailed one, and their whole litter had short tails. These remarkable kittens were designated a new breed: the American Bobtail.