People are being urged not to buy the feline equivalent of XL bully dogs, which have been created by breeders in the US.

The hybrid breed is understood to be spreading to the UK after being bred to resemble XL bully dogs, mixing the gene that causes hairlessness in sphynx cats with the gene responsible for the short legs of munchkin cats.

Experts have warned in a research paper that the breed is likely to have a life expectancy at least six years shorter than an average cat, as a result of suffering from serious health issues, the Telegraph reported.

Dr Grace Carroll, a specialist in animal behaviour and welfare at Queen’s University Belfast’s school of psychology, wrote in the Conversation: “Prospective pet owners need to be aware of the risks associated with owning mutant and experimental breeds.

“Consumers hold purchasing power. We can discourage breeders from prioritising aesthetics over the health and welfare of the animals by refusing to buy breeds with extreme traits.

“A fashion toward ethical breeding could ensure future cats are healthier, happier and free to enjoy natural feline behaviour like climbing, jumping and lounging in the sun. We should let cats be cats.”

The cat species is being promoted on social media, with breeders already offering them for sale in the UK, despite concerns over serious health defects.

As is the case with the sphynx breed, XL bully cats do not have whiskers, meaning they can have problems with communication and navigation.

Carroll said: “Kittens already have a limited ability to regulate their body temperature and this is made even more difficult by hairlessness and makes them more susceptible to respiratory infections. A lack of fur can also lead to sunburn and skin cancer in hairless cats.”

Short legs can also lead to a number of issues, experts have said. “Their short legs are a genetic defect which can lead to painful arthritis and cause problems with their general mobility,” said a Cats Protection spokesperson.

The NatureWatch Foundation, which campaigns on animal welfare and investigates the illegal trade in animals, added: “It’s shocking to see that these poor cats are starting to appear in the UK.

“We’ve seen increasingly extreme breeding practices in the dog world in recent years, and it appears unscrupulous people are now turning their attention to exploiting cats in the same way, all in the pursuit of greed and social media likes.”