Бесшерстные кошки Сфинкс: история и особенности породы

Hairless breed of cat

The Sphynx cat (pronounced SFINKS, '/s//f//ɪ//ŋ//k//s/) also known as the Canadian Sphynx, is a breed of cat known for its lack of fur. Hairlessness in cats is a naturally occurring genetic mutation, and the Sphynx was developed through selective breeding of these animals, starting in the 1960s. The skin has a texture of chamois leather, as it has fine hairs, or the cat may be completely hairless. Whiskers may be present, either whole or broken, or may be totally absent. Per the breed standards, they have a somewhat wedge shaped head with large eyes and ears, quite long legs and tail, and neat rounded paws. Their skin is the color that their fur would be, and all the usual cat markings (solid, point, van, tabby, tortie, etc.) may be found on the Sphynx cat's skin. Because they have no fur, Sphynx cats lose body heat more readily than coated cats, making them both warm to the touch and prone to seeking out warm places.

The Canadian Sphynx breed was started in 1966 in Toronto, Ontario when a hairless male kitten named Prune was born to a black and white domestic shorthair queen (Elizabeth). and Keese and Rita Tenhoves to develop a breed of cats which was subsequently renamed as Sphynx. The Bawas and the Tenhoves were the first individuals able to determine the autosomal recessive nature of the Sphynx gene for hairlessness while also being successful in transforming this knowledge into a successful breeding program with kittens which were eventually capable of reproducing. The Tenhoves were initially able to obtain for the new breed provisional showing status through the Cat Fanciers' Association (CFA) but ultimately had the status revoked in 1971, when it was felt by the CFA Board that the breed had concerns over fertility. The resulting litter produced five kittens: two males from this litter (Q. Ramses and Q. Ra) were used, along with Punkie's half sister, Paloma. The Sphynx's allele is termed "hr", for hairless. The only allowable outcross breeds in the CFA are now the American Shorthair and domestic shorthair. Other associations may vary, and the Russian Blue is a permitted outcross in the Governing Council of the Cat Fancy (GCCF).

The Sphynx's distinctive hairlessness is primarily due to a mutation in the KRT71 gene, which also affects other breeds, such as the Devon Rex and Selkirk Rex, albeit with different outcomes. This gene is responsible for the keratinization of the hair follicle. In the Sphynx, the mutation, known as "hr", leads to a complete loss of function, damaging the structure of the hair. Normally, KRT71 helps produce strong hair that is securely anchored to the skin. However, due to the "hr" mutation, the hair of Sphynx cats lacks a solid root or bulb, making it extremely weak. Consequently, the hair is fragile and loosely attached, causing it to fall out easily and contributing to the breed's nearly hairless appearance.

Sphynx are known for their extroverted behavior. They display a high level of energy, intelligence, curiosity and affection for their owners. They are one of the more dog like breeds of cats, frequently greeting their owners at the door and are friendly when meeting strangers. A study was conducted by the Journal of Veterinary Behavior in 2012, and while further research needs to be conducted, purebred Sphynx cats were rated by their owners as friendlier than purebred European cats.

Care should be taken to limit the Sphynx cat's exposure to outdoor sunlight at length, as they can develop sunburn and skin damage similar to that of humans. In general, Sphynx cats should never be allowed outdoors unattended, as they have limited means to conserve body heat when it is cold. In some climates, owners provide coats or other clothing in the winter to help them conserve body heat. While they lack much of the fur of other cat breeds, Sphynxes are not necessarily hypoallergenic. Allergies to cats are triggered by a protein called Fel d1, not cat hair itself. Fel d1 is a protein primarily found in cat saliva and sebaceous glands. The skin of the Sphynx cat is known for its excessive production of a greasy secretion, which often results in the accumulation of a sticky, dark brown, or reddish brown layer that necessitates regular cleaning. Furthermore, Sphynx cats typically produce more earwax than most hairy domestic cats. This increased wax production is attributed to the minimal to absent hair within their ears, which allows for the accumulation of dirt, skin oils (sebum), and ear wax, thereby requiring frequent cleaning. Additionally, they often accumulate oils and debris under their nails and within their numerous skin folds due to the lack of fur. Regular maintenance of these areas, including the nails and skin folds, is essential for the health and hygiene of the breed. The lack of hair can cause health issues with kittens in the first weeks of life because of susceptibility to respiratory infections. Reputable breeders should not let their kittens go to new homes without being at least 14 weeks of age to ensure the kitten is mature enough to cope in a new environment. In a review of over 5,000 cases of urate urolithiasis the Sphynx was over represented, with four recorded cases out of a population of 28.

The breed does have instances of the genetic disorder hypertrophic cardiomyopathy (HCM). Other domestic cat breeds prone to HCM include Persian, Ragdoll, Norwegian Forest cat, Siberian cats, British Shorthair and Maine Coon; however, any domestic cat including mixed breeds can acquire HCM. Studies are being undertaken to understand the links in breeding and the disorder. Cats are screened for HCM disease with echocardiography (ultrasound of the heart), as well as with additional tests determined by the veterinarian cardiologist including electrocardiogram (EKG, ECG), chest radiographs (X rays), and/or blood tests. These prevalences were found in cats with an average age of 2.62 years. Male cats developed more severe disease than female cats and often developed it earlier, at an average age of 19 months for males and 29 months for females. This condition has also been described, but is rarely seen. Cats affected by CMS show generalized muscle weakness and fatigue, as well as ventroflexion of the head and neck, head bobbing, and scapulae protrusion.