At first glance, the "Hairless" and "Powderpuff" varieties of Chinese Crested Dogs appear to be two different breeds, but hairlessness is a dominant trait within a single breed. The Hairless has soft, humanlike skin, as well as tufts of fur on its paws ("socks") and tail ("plume") and long, flowing hair on its head ("crest"). In addition to being a dominant gene, the "hairless" gene is lethal when homozygous. All living hairless Cresteds are therefore heterozygous for this trait.
The Hairless variety can vary in amount of body hair. Fur on the muzzle, known as a beard, is not uncommon. A true Hairless often does not have as much furnishings (hair on the head, tail, and paws). The difference between a very hairy Hairless and a Powderpuff is that the Hairless has a single coat, often with hairless parts on the body, while the Powderpuff has a thick double coat. The skin of the Hairless comes in a variety of colors, ranging from a pale flesh to black. Hairless cresteds often lack a full set of teeth, but this is not considered a fault.
The look of the Powderpuff varies according to how it is groomed. When its fur is completely grown out on its face, it strongly resembles a terrier; however, the Powderpuff is usually shaved around the snout as a standard cut.
The amount of body hair on the hairless variety varies quite extensively, from the true hairless which has very little or no body hair and furnishings, to what is called a hairy hairless, which if left ungroomed can grow a nearly full coat of hair. These hairy hairless are not a mix between powderpuffs and hairless Chinese Cresteds though, but is merely a result of the varying expression of the hairless gene, which the powderpuff does not have at all.
One famous Chinese Crested dog was the hairless purebred named Sam, who was dubbed the "World's Ugliest Dog" in competition from 2003 to 2005. He died before he could compete in 2006.
Maintenance of the Hairless variety's skin is similar to maintaining human skin - and as such it can be susceptible to acne, dryness, and sunburn. Hypoallergenic or oil-free moisturizing cream can keep the skin from becoming too dry when applied every other day or after bathing. Burning can occur in regions that lend themselves to strong UV-rays, especially in lighter-skinned dogs. Many owners apply baby sunscreen to their pets before spending time in strong sun. Some Cresteds have skin allergies to Lanolin, so be cautious when using any products that contain it.
Unless the dog is a "True" Hairless (one with virtually no hair growth on non-extremities), trimming and/or shaving is often performed to remove stubble growth.
The Chinese Crested is further distinguished by its hare foot, (having more elongated toes) as opposed to the cat foot common to most other dogs. Because of this the quicks of Cresteds run deeper into their nails, so care must be taken not to trim the nails too short to avoid pain and bleeding.
The crested is not affected by many of the congenital diseases found in toy breeds. They are, however, prone to some of the conditions below.
Cresteds have what is called a "primitive mouth". This means that most of their teeth are pointy like their canines. Hairless varieties of the Cresteds can be prone to poor dentition. Poor dentition may include missing or crowded teeth and teeth prone to decay when not properly cared for. Most dogs of the Puff variety have few, if any, dental defects.
Eyes are a concern within the breed, having at least two forms of progressive retinal atrophy (PRA) which can eventually lead to blindness. For one of these forms of PRA, there exists a genetic test, prcd-PRA. Since this test can only reveal the existence of affected or carrier status of this one form of PRA, breeders and owners of the breed should still have regular eye exams by veterinary ophthalmologists.
As with all other toy breeds, the Cresteds can be prone to patellar luxation. This inheritable condition is caused by shallow knee joints (stifles) and results in kneecaps that pop out of place. Its onset is often at a young age, and can cause temporary to permanent lameness based on the severity. Breeders should have their stock certified free of patellar luxation. Many countries' kennel clubs maintain a centralised registry for health results.
Allergy and autoimmune diseases has been observed in the breed. The severity of these ailments, often leading to the premature death of the dog means this is something breeders need to take seriously, in order to avoid this becoming a problem for the breed.
The lifespan of a Chinese Crested Dog can be quite impressive. Many well-cared-for Cresteds live to see 15 years or more.
The Chinese Crested was officially recognised by the Fédération Cynologique Internationale in 1987, by The Kennel Club (UK) in 1981, by the American Kennel Club in 1991, and by the Australian National Kennel Council in 1995.
The Powderpuff trait cannot be bred out because it is carried by all Chinese Cresteds (even the hairless ones). All Hairless Chinese Crested have the ability to produce Powderpuff puppies, even when they are bred to another Hairless. On the other hand, powderpuffs bred to another powderpuff can never produce hairless puppies, since they do not carry the hairless gene.