Guinea pigs are herbivores, so they feed on grass, herbs and vegetables. They do not need meat or other animal products. 

Guinea pigs can be fed a vegan diet without any problems, but care should be taken to provide a balanced and fresh diet. Some fruits and vegetables can also be poisonous.

Guinea pigs are vegan by nature

Guinea pigs originated in the Andes in South America and are still found in many parts of South America. There are different habitats there, so guinea pigs are very adaptable. Depending on where they live, they eat different plant parts in the wild, for example grasses, seeds, vegetables or fruits. 

Guinea pigs are herbivores, or plant eaters, and therefore eat a plant-based diet in any situation. Meat, eggs or the milk of other species are never on the menu of guinea pigs. Their digestion, teeth and behavior are geared towards eating plant material. 

What should be considered when keeping guinea pigs vegan?

A vegan keeping of the animals is possible without any problems concerning food. In addition, the most important aspects include a large run, which they can use daily. This should not fall below an area of 4 square meters.

In summer, the guinea pigs can live outside on a meadow, but always with a cage protected all around, so that neither martens nor birds nor other wild animals can get the defenseless guinea pigs. If the guinea pigs are also on the meadow at night, it is absolutely necessary to make sure that the cage also goes a bit into the ground. Otherwise, some wild animals can easily dig a hole under the cage and get the animals. 

As a rule, guinea pigs do not like to be petted. Therefore, they need their space and prefer to be simply among themselves. 

What to feed guinea pigs? 

The main food of guinea pigs is grass. Therefore, in spring, summer and autumn you should pick them fresh grass every day. In addition, you can also pick the animals dandelion, daisies, clover and others from the meadow. It is important that the bouquet always includes variety and, if possible, rarely includes a large amount of only one component.

Throughout the year, and especially in winter, it is best to give the guinea pigs new hay every day. Ideally, there should be a hayrack in the cage to protect the hay from urine and other contamination. Once the food is no longer fresh and clean, they usually do not eat it.

Guinea pigs have weak intestinal peristalsis. In order for their digestion to function smoothly, they need to eat food constantly. It is therefore important that raw fiber-rich food such as hay is always available to the animals. Even in the wild, guinea pigs spend most of their waking hours eating. This also allows them to meet their high energy needs.

It should be noted that guinea pigs – like us humans – are among the few animals that do not produce vitamin C themselves. They must therefore take it in with their food. Grass or hay contains little vitamin C, which is why it is important to feed the guinea pigs also vegetables, fruits and wild herbs. For example, hot peppers, nettles and fennel are especially rich in vitamin C.

Fruits should not be fed more than once a week due to their high sugar content. This contributes to good health and digestion of rodents. Vegetables and wild herbs of all kinds – with the exception of those listed below – on the other hand, can and should be fed daily.

In addition, you can offer the rodents mixed food from the pet store. This will help the guinea pigs to wear down their teeth, which are always growing back. 

Fresh water should be available to the guinea pigs at all times, ideally in a drinking bottle. Open bowls with water quickly collect contamination, and there is also a great risk that the rodents will knock over the bowl and, in the worst case, have to go without water. The water in the drinking bottle should be changed daily. 

What not to feed guinea pigs?

There are some things you should not feed guinea pigs – either because they upset their digestion or can even be poisonous. 

Things to avoid are:

• Legumes: chickpeas, lentils, soybeans, etc.
• Nuts: Tree nuts, hazelnuts, Brazil nuts, pecans, cashews, etc.
• Potatoes
• Stone fruit
• Cauliflower
• Spring cabbage
• Kohlrabi
• All other types of cabbage, as they can cause flatulence and severe diarrhea, which is dangerous for the animals
• Onions, chives, garlic, leeks 
• The following things should never be fed to guinea pigs as they can be toxic:
• Avocado
• Exotic fruits: mango, orange, lemon, papaya, pomegranate, cherimoya,
• Rhubarb
• Cyclamen
• Hogweed
• Boxwood
• Ivy
• Monkshood
• Fern
• Foxglove
• Lilac species
• Buttercup
• Elder
• Lilies
• Lily of the valley
• Daffodils
• Primroses
• Snowdrops
• Belladonna
• Juniper
• Conifers: pine, fir, spruce, etc. 
• Willows
• Oak
• Yew
• Thuja

Do guinea pigs need food supplements?

Guinea pigs do not depend on an additional supply of minerals and vitamins. They absorb all the nutrients they need through a varied, fresh diet. Salt licks are also not necessary. Guinea pigs can even develop urinary and kidney stones from minerals added over a long period of time. 

Guinea pigs synthesize vitamins B and K in the appendix itself. These vitamins are then made usable by the organism through the reabsorption of this appendix feces. Unlike the normal, dark feces that the animals excrete, the appendix feces is light in color and coated in mucus. They swallow this unchewed, where it continues to ferment in the stomach for several hours. This eating of the appendix feces (cecotrophy) usually looks like a grooming motion. This intelligent process ensures that the animals get extra vitamins.  

Can guinea pigs drink milk?

Guinea pigs can digest cow’s milk, but it goes against their nature to drink milk from other species. Guinea pigs suckle from their mother for up to three weeks after they are born. After that, they no longer need the milk and, like us humans, break down the enzyme lactase, which they need to digest the milk sugar lactose.

Nevertheless, guinea pigs can still digest milk even at an advanced age. However, this can trigger allergies. Goat milk showed a smaller risk of allergies in guinea pigs in one study.

Do guinea pigs need milk?

So it is quite possible that your own guinea pigs can tolerate cow’s milk in small amounts. In pet shops you can also buy drops that contain cow’s milk, usually these come in the form of “yogurt drops”. In addition to lactose, milk often contains residues of substances such as hormones, medications and other undesirable substances. These make the milk from cows and other so-called farm animals unsuitable for rodents.

Also cheese, yogurt or lactose-free milk should never be fed to guinea pigs. Besides the undesirable residues already described, dairy products also contain too much fat and calcium for the little animals.

Drops with milk and other milk-containing treats can therefore be dispensed with a clear conscience. Guinea pigs do not need these for their health – they can even harm them.

In general, it makes little sense to want only the best for the guinea pigs and at the same time to sacrifice so-called farm animals for its milk. Vegans believe that all animals have the right to life – not only the guinea pig, but also cows, pigs, chickens and goats.

However, if a guinea pig has accidentally eaten a piece of cheese or other dairy products, this is not a tragedy. The guinea pig will not die from it. However, it is quite possible that eating dairy products will upset the guinea pig’s digestion and cause constipation or diarrhea. To spare the guinea pig this stress as much as possible, you should take good care in the run that no unsuitable food is lying around.

Can guinea pigs eat (chicken) eggs?

Guinea pigs would never eat eggs in the wild. A hen’s egg also contains no nutrients that a guinea pig does not already get from species-appropriate food. It is therefore unnecessary, and even dangerous, to give herbivorous guinea pigs products containing egg components.

We are not aware of any studies that have investigated the effects of egg consumption in guinea pigs. Accordingly, it is unclear whether rodents could digest eggs. It is quite possible that consumption – similar to cow’s milk -. Diarrhea or other digestive disorders would trigger.

Can guinea pigs eat meat?

Guinea pigs would never eat other animals in the wild. A species appropriate feeding would be to mimic the natural diet at home. So you should never feed meat to guinea pigs.

Meat contains no fiber, which is so important for their digestion (see above), only unnecessary protein, fat and possibly residues of hormones, drugs and others. Meat does not contain nutrients that guinea pigs do not get from a varied diet. 

The intestines of guinea pigs are designed to digest plant material. The intestines of carnivores such as wolves are shorter and have different enzymes. So it is questionable whether guinea pigs could digest meat. No studies can be found on this at present. Pretty sure, however, the animals would have gross digestive problems if they actually ate raw meat.

If guinea pigs have ever accidentally eaten raw or cooked meat, an immediate call to the veterinarian in charge is recommended.  

These questions might also arise:

Can guinea pigs drink oat milk?

Oats are a safe food for guinea pigs. There is usually a large amount of oats in guinea pig food available at pet stores. Oat milk, which consists only of oats, water and possibly some salt and sunflower oil, should therefore not be a problem for guinea pigs. Nevertheless, there is no reason to offer guinea pigs oat milk, as they already receive all the nutrients when fed in a species-appropriate way.

Can guinea pigs drink almond milk?

Guinea pigs should not drink almond milk. Almonds contain small amounts of prussic acid, which can be fatal to guinea pigs if given over a long period of time. There are currently no studies on feeding almond milk to guinea pigs, so it should definitely be avoided.