Animals Pets Hairless Guinea Pigs Are a New Pet Craze By Jaymi Heimbuch Jaymi Heimbuch Twitter Writer California Polytechnic State University, San Luis Obispo Jaymi Heimbuch is a writer and photographer specializing in wildlife conservation, technology, and food. She is the author of "The Ethiopian Wolf: Hope at the Edge of Extinction." Learn about our editorial process Updated February 9, 2022 Share Twitter Pinterest Email Emmanuelle Grimaud / Getty Images Animals Wildlife Pets Animal Rights Endangered Species In This Article Expand Where Did They Come From? Hairless Guinea Pig Care Different Breeds Guinea pigs have been a favored pet for a while. There's even a National Adopt A Rescued Guinea Pig month to help find homes for guinea pigs so people will avoid buying them from a store. And yes, there are even Internet-famous guinea pigs. Now entering the scene is a hairless version, affectionately called a skinny pig, a strain that has only been around for a few decades. These hairless guinea pigs have become increasingly popular, with prices reaching upward of $150. They have a surprising history and a unique set of needs. Hairless Guinea Pig Facts Hairless guinea pigs, also known as skinny pigs, are very similar to their furry relatives. A fully grown adult will weigh an average of 1-2 lbs and be up to 12 inches long. Their lifespan is 5-7 years in domestic settings.Despite their name, hairless guinea pigs do have some hair on their muzzle, back, and legs. Since they don't have fur to help them regulate their internal temperature, they need to live in environments between 65 F and 75 F and be shielded from direct sunlight. Where Did Hairless Guinea Pigs Come From? Ukjent / Getty Images There's a bit of controversy about the introduction of hairless guinea pigs; they didn’t exactly have a natural start. While guinea pigs are native to Peru and were domesticated around 5000 BC, hairless guinea pigs originated in a laboratory around 40 years ago. In 1978, a lab in Montreal bred a colony of guinea pigs in which a genetic mutation was identified. The spontaneous genetic mutation resulted in hairlessness, and the researchers pursued the strain. The hairless guinea pigs were originally inbred to keep the strain going, with new-haired guinea pigs added into the breeding program later on. This meant that the first generations of hairless guinea pigs were prone to illnesses and immune problems. However, with about four decades of careful breeding, the strain has developed into heartier, healthier guinea pigs. Alexandra Jursova / Getty Images Still, their origins are from lab animals used for testing, and many people concerned with animal welfare—as well as the abundance of animals bred specifically for trends in the pet industry—have expressed concerns about hairless guinea pigs becoming so popular. Because their skin has a structure, composition, and characteristics similar to human skin, they may be used as animal models for dermatological research. Hairless Guinea Pig Care Olena Kurashova / Getty Images Though today’s hairless guinea pigs are healthier, they still require special care. Because they lack a fur coat, they get cold easily so they must be indoor pets. If they are permitted some outdoor time on warm days, they need sunscreen to protect their sensitive skin. They also eat more than regular guinea pigs. This is because they have a higher metabolism as their bodies work harder to stay warm. A fur coat usually protects an animal's skin from injury, but the hairless guinea pigs lack this soft armor. So, owners need to be extra careful to protect their pets from harm. Despite being a higher maintenance pet than traditional guinea pigs, hairless guinea pigs have some benefits. Because they lack hair, they are ideal for animal lovers with allergies. For those folks who want a pet but can't be around pet hair, these gregarious, social animals are a great option. They even come in different skin pigmentations that offer variations in color, including chocolate, cinnamon, silver, golden, white, and more. Different Breeds Aksana Kavaleuskaya / Getty Images There are two breeds of hairless guinea pigs: the skinny pig, which originated in a lab, and the Baldwin, which is the result of a genetic mutation in white-crested cavies discovered by a Californian breeder. The differences between the two breeds are in the hair they do have and when. Skinny pigs are born without hair and stay that way, except for a bit of hair on the ends of their nose and their feet. Baldwins, on the other hand, are born with hair that falls out gradually over the first few months of life, and from then on they are entirely bald. Other than their hair situation, hairless guinea pigs are no different from other guinea pigs in their behavior, their love of attention, and their individual—usually outgoing—personalities. Why Pets Matter to Treehugger At Treehugger, we are advocates of animal welfare, including our pets and other domestic animals. The better we understand our fellow creatures, the better we can support and protect their wellbeing. We hope our readers will adopt rescue pets instead of shopping from breeders or pet stores, and will also consider supporting local animal shelters. View Article Sources H. Frederick Frasch & Ana M. Barbero. "A paired comparison between human skin and hairless guinea pig skin in vitro permeability and lag time measurements for 6 industrial chemicals, Cutaneous and Ocular Toxicology." Vol. 28, Issue 3, 2009. doi: 10.1080/15569520902950474 Miyauchi, Hiroko, and Takeshi Horio. "A New Animal Model For Contact Dermatitis: The Hairless Guinea Pig." The Journal Of Dermatology, vol 19, no. 3, 1992. doi: 10.1111/j.1346-8138.1992.tb03197.x "Discover Hairless Guinea Pigs: Skinny Pigs & Baldwin Guinea." AZ Animals.