Guinea pig care: from the cage to the food bowl

The guinea pig has a reputation as an undemanding first pet, but it has one peculiarity that nature took away from it: it cannot make its own vitamin C. That, rather than cage size or bedding choice, is the most common cause of problems in pet guinea pigs. This guide works through the essentials, from housing to the food bowl.

Why vitamin C is crucial

Guinea pigs are among the few mammals (along with humans) that cannot produce vitamin C themselves – they lack a working L-gulonolactone oxidase enzyme. All of their vitamin C therefore has to come from food, every day.

Veterinary sources give a daily requirement of roughly 10–25 mg of vitamin C per kilogram of body weight in adults, and 30 mg/kg or more for pregnant, nursing, growing or sick animals. A deficiency leads to scurvy: the animal becomes inactive, walks with difficulty, joints swell, the coat deteriorates and the gums bleed.

Hay: the basis, not an extra

Good meadow hay must be available without limit. It supplies the fibre the digestive system needs and wears down teeth, which grow throughout a guinea pig's life. Hay should be dry and fragrant, free of dust and mould. Because of its high calcium content, alfalfa suits only young animals and pregnant or nursing females, not healthy adults.

Fresh vegetables every day

Vegetables are the most reliable source of vitamin C. Particularly rich ones include:

• bell peppers (red and green) – one of the best choices,
• parsley and leafy greens such as kale and chard,
• tomato (without the green parts and leaves),
• spinach and beet greens – in moderation, because of oxalates.

Introduce any new food gradually and watch the droppings. Remove uneaten fresh food the same day so it cannot go mouldy. Fruit is a treat only, because of its sugar.

The cage: floor space matters more than fittings

Guinea pigs run and explore rather than climb – what they need above all is a large, uninterrupted floor area, not multiple levels. The cage should have a solid floor (wire floors damage their feet), a deeper layer of absorbent paper or unscented wood-shaving bedding, at least one hide per animal and a hay rack.

Place it in a quiet spot away from draughts and direct sun. Guinea pigs tolerate heat poorly – above roughly 26 °C they overheat quickly, so watch for shade and ventilation in summer.

Water, grooming and the daily check

Fresh water must always be available; clean the bottle weekly and check that the ball valve is not sticking. Long-haired breeds need regular brushing, and in all guinea pigs the claws should be checked periodically.

Each day take a quick look at whether the animal is eating, drinking and passing droppings normally. If a guinea pig stops eating, hides away or breathes with effort, do not wait – in small herbivores the situation deteriorates quickly, so a veterinarian who treats small pets is needed.

Before you bring one home

Details on the species, temperament and expected lifespan are on our guinea pig page. If you are still deciding between small rodents, compare the requirements with the Syrian hamster – the needs differ considerably, as our guide What cage does a hamster need makes clear.

All of the above is informational and does not replace an examination by a veterinarian; for any health problem, always consult a specialist in small pets.