What is the ideal diet for my small animal?

Author: Hannah Dyball
Published: Thursday 18th September 2014
Updated: Thursday 23rd January 2020

Rabbits, guinea pigs, hamsters, mice. Or, as they are collectively known, small animals.

You'd be forgiven for thinking this category also extends to fish, insects and other tiny creatures, but when we talk about 'small animals,' we tend to be referring to the four-legged, furry variety. Even the more exotic ferrets, chinchillas and degus come under the small animals umbrella these days.

Increasingly, small animals have become popular domestic pets, with roughly 3.5% of UK households now owning rabbits and guinea pigs. As many as 100,000 gerbils are owned in Great Britain, despite being one of the least popular pets behind lizards, pigeons and tortoises according to a recent study.

Compared to dogs, cats and horses, small animals have a relatively short life expectancy and are far less demanding of money and time. This means that people sometimes cut corners when it comes to their diet. Yes, they are small, but the life expectancy of these animals is just as much a product of their diet as it is anything else. A rabbit fed the right balance of vitamins and roughage may well live a year or two longer than a rabbit fed a muesli-style dry food.

In the wild, rabbits and guinea pigs grazed almost continuously on the varied forage of the land, slowly digesting the high levels of fibre their bodies needed to survive. Their systems were adapted for this and long periods of chewing grass and similar foods kept the teeth at a healthy length - essential, bearing in mind the teeth never stop growing. Without a diet consisting of regular forage, rabbits and guinea pigs do not get the nutrition they need for healthy growth and repair.

While it may be tempting to feed domestic rabbits and guinea pigs a dry commercial pellet and forget about the rest, this type of diet is very harmful. If animals are housed exclusively inside with no access to grass or similar forage, all aspects of health will suffer. Whether housed inside or out, rabbits and guinea pigs must always have hay available to them. If they don't, one of the worst consequences is that their teeth overgrow and they can no longer eat. Rabbits that don't chew hay are also more prone to weight gain as their digestion is not being slowed down.

While alfalfa is often recommended for small animals, too much of it (alfalfa-based hay or alfalfa-based pellets) can cause urinary crystals due to its high calcuim content. Timothy hay is possibly the best type of hay for rabbits and guinea pigs as it is high in essential fibre, low in protein and calcium, and full of beneficial goodness for the gastrointestinal tract.

It is advised that you avoid feeding rabbits and guinea pigs 'muesli-style' dry food as they will pick out the bits they like and leave the rest. The 'rest' usually means the healthy bits they are supposed to eat and that are most nutritionally valuable. Premium pellets with a uniform appearance are the best type of dry food as your pet won't have the option to be selective and will readily consume all the goodness. If your rabbit weighs over 3.5kg, the recommended guideline for dry pellets is 1-2 tablespoons daily when fed alongside hay and other roughage (i.e. grass, weeds, plants and herbs). To view our complete range of small animal diets, click here.

Fresh vegetables are also an important part of diet and should be fed regularly, but in moderation. Rabbits and guinea pigs have delicate digestions so always introduce a new food gradually to avoid stomach upsets and diarrhoea. Fruits should not be fed often as they are high in sugar and most small animals would not naturally eat them. Many fruits pose a hazard by containing poisonous pips, stones and leaves that may be choked on if consumed. The occassional apple or pear will do your animal no harm but it is up to you to limit its sugar intake. Additional treats should be kept to a minimum, although wooden chews and mineral stones are helpful for maintaining good dental health.

Here is a list of vegetables and fruits that are suitable for both rabbits and guinea pigs:

- Broccoli

- Cabbage

- Cucumber

- Green beans

- Peppers (red, green and yellow)

- Carrots

- Beetroot

- Chicory

- Courgette

- Asparagus

- Baby sweetcorn

- Fennel

- Apple

- Banana

- Grapes

- Melon

- Mango

- Pineapple

- Plums

- Strawberries, raspberries and blueberries

Hamsters and gerbils also benefit from a small helping of fresh food, although they require a lot less than rabbits and guinea pigs do. In the wild, hamsters would usually eat seeds and insects, so sugary fruits aren't naturally consumed, neither are they particularly beneficial. A daily ration of raw green vegetables is both a treat and a valuable nutritional supplement. Alfalafa and hay can be given but these are not essential for healthy digestion.

Grapes and rhubarb can be poisonous to small rodents so avoid these and offer something else instead (i.e. cabbage, carrots, broccoli). Other foods to avoid include raw beans, iceberg lettuce, citrus fruits and tomatoes. Commercial treats should always be given in moderation. Because hamsters are nocturnal, the best time to feed them is at dusk, when they wake up.

More importantly for gerbils and hamsters are grains and seeds, which should make up 15-20% of the daily diet. The seeds contain essential oils for coat, skin and eye health. Sunflower and pumpkin seeds are cited as a favourite with hamsters and gerbils, although feeding these should be fairly restricted. Budgie and canary mixes are a good supplement for rodents, alongside a small quantity of commercial dry food, specially made for hamsters and gerbils.

(For some reason, many people are tempted to feed their hamsters dog kibble and wet cat food, despite the fact they are omnivores (that will only naturally eat small insects), not carnivores. Vets recommend against this for obvious reasons, even if a hamster appears to enjoy its offering).

Chinchillas and degus eat a similar diet, plus or minus a few exceptions. For a start, chinchillas eat very small amounts. In the wild, they would've mainly eaten desert grasses and roots and so are ill-adapted to digesting high fat and high protein foods. They also have a hard time processing large amounts of green plants. Rabbits and guinea pigs may love vegetables, but chinchillas struggle to tolerate them, being very susceptible to diarrhoea. People tend to forget that chinchillas lived in dry places and so are dependent on a very dry diet.

Because of the chinchilla's sensitive gut, ensuring the correct diet may mean the difference between life and death. A high quality pellet and a supply of Timothy hay will meet all your chinchilla's dietary needs. When it comes to chinchillas, it is important to largely avoid nuts and seeds which are high in fat and make any food changes very gradually. The PDSA cites the following vegetables as being unsafe for chinchilla consumption:

- Broccoli

- Cabbage

- Lettuce

- Rhubarb

- Spinach

- Asparagus

- Peas

Degus has very similar dietary needs to chinchillas, being strict herbivores. They require large amounts of fibre in their diet and will often reingest their droppings to reabsorb the nutrients and maintain healthy gut function. It is important to remember that degus are highly intolerant to dietary sugar and can develop diabetes mellitus from consuming molasses, honey and glucose syrup. For this reason, it is well worth only feeding your pet treats intended for degus, as opposed to treats intended for other small animals. Avoid feeding your degu rabbit or chinchilla mixes as these often contain dried fruit pieces which are not suitable for regular consumption.

The best option for feeding domestic degus is to go with a high quality, dry food pellet or mix. An adult degu should ideally be fed 10g of hard food every day. Your degu should also have access to roughage i.e. hay and grass, as well as a small helping of fresh vegetables once or twice a week. A mineral or seed block will help maintain dental health to a good degree and will give your degu something to do during the day. Many degu owners swear by carrot and vegetable juices as a delicious and nutritious treat their pets go crazy for!