The modern line of skinny pigs originated from a cross between furry guinea pigs and a line of hairless experimental pigs . The hairless strain to which it is most likely related is a spontaneous genetic mutation first identified at Montreal ‘s Armand Frappier Institute in 1978, in a colony of guinea pigs in the Hartley laboratory. In 1982, they were sent to Charles River Laboratories for breeding for laboratory use and are commonly used in dermatological studies today. ^[1] They are an alien strain with an intact thymus ^[2] and a standard immune system. ^{[3] [ need better source ]}

Unique features

Physiologically, hairless guinea pigs do not differ significantly from regular furry guinea pigs, ^[4] although they need to eat more to maintain their body temperature. The optimal temperature range for hairless guinea pigs is 68 to 79°F (20 to 26°C), which is slightly higher than the optimal temperature range for furry guinea pigs. ^[2]

Their sensitive skin is very similar in appearance to human skin, ^[5] but has the same needs as normal guinea pig skin. Exposed skin is susceptible to sunburn, other wounds, and fungal infections unless precautions are taken. ^[4] Skinny pigs have also been found to have a higher risk of certain eye diseases than hairy guinea pigs. ^[6] Skinny pigs should be kept indoors and they are often kept in nesting materials such as blankets or fabric bags to retain heat. ^[4] The breeding process for skinny pigs requires outcrossing with hair-bearing pigs at least for other generations. ^[4] This is an important step in the breeding process, making them a poor choice for beginner breeders. Skinny pigs are born almost hairless and must maintain that hair level throughout their lives. ” Werewolves ” is a slang term for pigs that are skinny and have more hair than usual, extending all the way down their face and down to their neck and shoulders. Extremely hairy werewolf-type skinny pigs will have hair that reaches all the way to their rump. Werewolves often increase or decrease their hair based on hormone levels, especially hormones related to pregnancy. ^[7]

The gene that causes hair loss in skinny pigs is recessive , and raising two skinny pigs together will always result in all the piglets being skinny pigs. Breeding a skinny pig with a standard furry guinea pig will produce offspring that all carry one copy of the gene, but none will exhibit hairlessness. ^[8] These offspring are often called skinny carriers. Breeding two animals that carry the skinny gene together will result in an average of 25% of the offspring being skinny pigs, 50% of the offspring being skinny carriers, and 25% of the offspring being normal hair guinea pigs not carrying the gene. ^[9] Because the chances of getting a skinny pig are low and because it is impossible to visually distinguish the difference between a carrier guinea pig and one without the gene, this method of breeding is not recommended. encourage.

Those carrying the skinny-haired gene remain furry for life and look like a normal guinea pig despite carrying the hairless gene.

There is a second type of hairless guinea pig called the Baldwin guinea pig , but its hairlessness is the result of a completely different recessive gene. Breeding a skinny pig with a Baldwin guinea pig will produce piglets that are both hairless and carry one copy of the gene for hairless skinny pigs and one copy of the gene for hairless Baldwin pigs. . ^[9]

Although the skinny is a relatively new breed to pet owners and cavy lovers, it is becoming popular in Canada, Europe, Scandinavia and Russia as well as in the United States, where it was introduced. enter the pet trade around mid to late year. late 1990s.