The pet guinea pig

The guinea pig is a small, sociable herbivore that must live with at least one companion of its own kind and get vitamin C from its diet every day, because its body cannot make it. It lives 4 to 8 years on average and needs more space than most cages sold for it allow.

It shares the rabbit’s ever-growing teeth and hay-based diet, but differs on points that change everyday care. The two species should not be housed together.

Key facts before adopting

• Never alone: the RSPCA recommends at least one other compatible guinea pig, unless a vet or clinical animal behaviourist advises otherwise; the PDSA speaks of two or more, or groups of three. The pairings cited (a neutered male with one or more females, two females, brothers raised together) are possibilities, not guarantees: see how many guinea pigs should you get and can a guinea pig live alone?
• Vitamin C every day: like humans, guinea pigs cannot produce it, and a deficiency causes scurvy. Guinea pig pellets contain it, but it breaks down within months: the PDSA advises using pellets within three months of purchase. Rabbit pellets do not contain enough. The details are in how much vitamin C a guinea pig needs.
• Unlimited hay: it makes up 80 to 90% of the diet and wears down the continuously growing teeth. Fresh vegetables complete it, at about one cup per guinea pig per day according to the PDSA; the full diet is set out in what do guinea pigs eat.
• More space than a pet-shop cage: the Merck Veterinary Manual sets a minimum of about 106 × 61 cm for a single animal, and the PDSA recommends a hutch of at least 1.5 × 1 m linked to a run of at least 2 × 1 m. These two guides do not describe the same set-up: see what size cage or enclosure for two guinea pigs. Provide one more hiding place than there are animals, and never a wire floor, which hurts their feet.
• Sensitive to heat: the ideal temperature is around 17-20°C according to the RSPCA, 18-24°C according to Merck. Heatstroke risk starts from 26 to 29°C depending on the source.
• Sex them correctly before adopting: a female can become pregnant from 3 weeks of age (PDSA). A single pet-shop sexing mistake is enough to cause an unexpected litter.
• An exotics-savvy vet: like all prey animals, guinea pigs hide their symptoms. Difficulty breathing, droppings that stop or a loss of appetite call for a vet visit without delay. Never give a guinea pig an antibiotic without a veterinary prescription.
• No new pairing with a rabbit: the two species communicate differently, have different dietary needs, and rabbits can carry a respiratory bacterium that is dangerous to guinea pigs. For animals that already live together, the RSPCA adds a nuance: see can rabbits and guinea pigs live together? Rabbit needs are covered in the pet rabbit species guide.

Breeds and coat types

The Merck Veterinary Manual counts at least 13 recognised breeds, from short smooth coats to long hair, Abyssinian rosettes and hairless varieties. All share the same anatomy and needs. Breed mainly changes coat care: the PDSA recommends daily brushing for long-haired guinea pigs and once or twice a week for short-haired ones.

Further reading

Before adopting

• Rabbit or guinea pig: which should you choose?
• How long do guinea pigs live?
• How many guinea pigs should you get, and which pairings work?

Feeding

• What do guinea pigs eat?
• How much vitamin C does a guinea pig need?
• What vegetables can guinea pigs eat?
• Foods guinea pigs should not eat

Housing and social life

• What size cage or enclosure for two guinea pigs?
• Best bedding for guinea pigs
• Can a guinea pig live alone?
• Can rabbits and guinea pigs live together?

Health

• My guinea pig is not eating: what to do
• Scurvy: signs and treatment

Sources

• RSPCA — Keeping guinea pigs together
• RSPCA — Creating a good home for guinea pigs
• PDSA — Guinea pigs as pets
• PDSA — The ideal home for your guinea pigs
• PDSA — Introducing guinea pigs
• RSPCA — Keeping rabbits and guinea pigs together
• PDSA — Guinea pig health
• Merck Veterinary Manual — Guinea pigs
• VCA Animal Hospitals — Health problems in guinea pigs