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A healthy diet for guinea pigs

Feeding your guinea pigs the right food is essential to keeping them happy and healthy. Here's what your guinea pigs need for a good diet.

Hay and grass

Good-quality hay should make up most of your guinea pigs' diet, and they should always have it available to them. They should have fresh grass as often as possible too, ideally every day. They naturally graze, eating only grass, herbs and some other plants (such as dandelion or groundsel) for long periods, both day and night.

Remember, guinea pigs need hay and/or grass for their digestive systems to function properly. Also, their teeth are always growing, and eating hay helps wear them down to keep them at the correct length and shape. The wrong diet can cause serious dental disease.

Lawnmower clippings will make them ill

Never feed your guinea pigs lawnmower clippings, which will upset their digestive systems and make them ill.


Guinea pigs have special dietary needs and must get enough Vitamin C, so give them a fresh portion of grass-based guinea-pig pellets each day, as per the manufacturer's instructions. These provide essential Vitamin C, which is destroyed with exposure to air.

Don't just top up the bowl and ensure the pellets are eaten by the best before date. Your guinea pigs may need a larger portion of pellets if they're growing, pregnant, nursing or underweight. Ask your vet for advice on portion sizes if you're not sure.


Your guinea pigs should have fresh, washed leafy greens or weeds each day, such as kale or broccoli, which are excellent sources of Vitamin C. Guinea pigs don't naturally eat fruit or root vegetables, but you can give them in small amounts as treats, such as small pieces of carrot or an apple quarter. Don't give them citrus fruits, and remember that some plants are poisonous to guinea pigs.

A few things to remember about feeding your guinea pigs

Make sure they have fresh clean drinking water continuously and check it twice daily. Ensure water doesn't freeze in winter. Without water guinea pigs become seriously ill.

  • Adjust feeding quantities to prevent them from becoming underweight or overweight. The quantity of food guinea pigs need depends on their age, lifestyle and general health. They become overweight and may suffer if they're eating more than they need.
  • Avoid sudden changes in their diet - introduce new foods gradually.
  • Monitor the amount they eat/drink and their droppings - guinea pigs produce two dropping types - hard, dry pellets, and softer, moist pellets that they eat directly from their bottom and are essential to their diet.

Consult your vet immediately if you notice any changes in your guinea pigs' eating, drinking and/or toilet habits. For example, a sign of illness could be if their droppings stop, are less frequent or softer than usual and stick to their back. If you haven't registered with a vet, find your nearest vet practice.

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