Guinea Pigs: Feeding

What do guinea pigs eat in the wild?

The wild guinea pig, in its native habitat of the South American forests, eats everything from fruits, leaves, and plants to root vegetables, but especially a lot of high-fiber grasses.

What should I feed my guinea pig?

Guinea pigs, like rabbits, are herbivores (plant eaters), although their gastrointestinal system is not as well understood as the rabbit. Guinea pigs develop food preferences early in life and do not easily adapt to changes in food types, appearances, or presentation. Sudden changes can result in a refusal to eat, so make any changes to your guinea pig’s diet gradually.

A healthy guinea pig’s diet should include:

• Unlimited timothy or other low-calcium hay
• A smaller amount of commercial, high-fiber, timothy-based guinea pig pellets
• A variety of fresh leafy greens and vegetables, including foods high in vitamin C

Hay

Hay is the most important part of a guinea pig’s diet. Offer unlimited timothy or other low-calcium hay throughout the day. Hay provides the fiber guinea pigs need to keep the bacteria in their intestinal tract healthy and functional. Chewing hay also helps wear down their continuously growing teeth.

Vitamin C and pellets

Guinea pigs have a critical dietary requirement for vitamin C and can develop scurvy if their diet does not contain adequate amounts. Vitamin C should be provided through their pelleted food and vegetables. Offer a commercial, high-fiber, timothy-based guinea pig pellet. If your guinea pig consumes a pelleted diet with stable vitamin C, timothy hay, and some green leafy vegetables, then vitamin C supplements are not necessary.

Fresh vegetables

Supplement hay and pellets with a variety of fresh, well-washed, leafy greens and colored vegetables. Do not offer iceberg or head lettuce, as they have little nutritional value and contain mostly water. Good choices include:

• Vegetables high in vitamin C: Bell pepper, tomato, turnip, collard greens, and asparagus
• Other vegetables: Green and red leaf lettuce, romaine lettuce, broccoli, cauliflower, endive, carrot tops, beet greens, cilantro, carrot, and squash

Fruit and other foods

Offer fruit only occasionally and in small amounts. Fruit is high in sugar, and feeding too much may lead to an imbalance of intestinal bacteria, which may cause serious and potentially life-threatening diarrhea. Occasional choices include fruits high in vitamin C, such as orange and kiwi, or high-fiber fruits such as pear and apple. Do not feed your guinea pig oats, seeds, nuts, or dry cereals, as these foods are too high in carbohydrates and fat.

How much water does my guinea pig need?

Fresh, clean water should be available 24 hours a day. You can offer water in a sipper bottle or a heavy crockery bowl that will not easily tip over. Clean all food bowls, water bowls, and water sippers every day with soap and hot water and rinse well. 

Check to ensure the sipper tube is not clogged with food or algae. A bottle brush should be used to thoroughly clean the sipper bottle tube, as it is a great place for bacteria to grow. Change the water at least daily, even if there is still water available, as bacteria and yeast can accumulate if water is not changed.

Why do I need to give my guinea pig vitamin C?

Guinea pigs cannot manufacture their own vitamin C, so they must get adequate vitamin C through their diet. Vitamin C is essential for the normal development and maintenance of skin, joints, and mucosal surfaces, such as the gums. It also plays an important role in wound healing. A chronic lack of vitamin C can lead to scurvy and make guinea pigs more prone to diseases, infections, and skin problems.

Guinea pigs with vitamin C deficiency should be seen by a veterinarian as soon as possible. Signs of deficiency may include:

• A rough hair coat
• Loss of appetite
• Diarrhea
• Reluctance to move or signs of pain
• Swollen feet or joints
• Hemorrhages or ulcers on the gums or skin

How much vitamin C does my guinea pig need?

Guinea pigs need 10 mg to 50 mg of vitamin C per day. The amount your guinea pig needs depends on factors such as age, overall health, stress, and pregnancy. Your veterinarian can tell you how much vitamin C your guinea pig requires.

How should my guinea pig get vitamin C?

Vitamin C can be provided through vitamin C-fortified guinea pig pellets and fresh green or colored vegetables. Guinea pigs eating a good-quality diet that provides adequate vitamin C and consuming fresh green or colored vegetables usually do not require an additional vitamin C supplement. Your veterinarian can advise you if your guinea pig needs a vitamin C supplement.

Vitamin C in guinea pig pellets is relatively unstable and breaks down (oxidizes) quickly. Be sure to use or replace your guinea pig’s pellets within 90 days of the date of manufacture. After that time, the vitamin C in the pellets may no longer be at an adequate level.

Have your guinea pig examined annually by your veterinarian and discuss your guinea pig’s specific dietary and vitamin C needs at these visits.