Munchkin

Cat

The Munchkin is a cat breed created by a naturally occurring genetic mutation that results in cats with abnormally short legs. However, the shortness of their legs does not seem to interfere with their running and leaping abilities. The gene responsible has been compared to the one that give Welsh Corgis, Basset Hounds and Dachshunds their short stature; however, Munchkins do not suffer from the many spinal problems that are typically associated with those canine breeds as cats' spines are physically different from dogs'. The spine of a Munchkin cat is usually indistinguishable from that of other cats.

http://en.wikipedia.org/wiki/Munchkin_(cat)