Caring For Your Pet Mouse: A Comprehensive Guide

Mice are social, inquisitive, and entertaining pets that require a gentle hand. They are active and generally nocturnal, sleeping during the day and becoming most active at night. They are also very intelligent and enjoy playing with toys, such as cardboard boxes and tubes.

Mice are omnivores and should be fed a combination of commercial food and treats. They need a protein level of at least 16% and a fat content of 4-5%. Fresh fruit and vegetables should be included in their diet, such as apples, berries, broccoli, carrots, and peas.

Mice are sensitive to light and noise. They are susceptible to heat stress, which can be fatal, so it is important to keep them in a well-ventilated area that is sheltered and protected from direct sunlight and strong winds.

Mice are easy to care for but require a commitment as they usually live for about three years.

Housing: an aquarium or wire cage with substrate

When it comes to housing your pet mouse, there are a few options to consider. Firstly, it is important to ensure that the enclosure is large enough for your mouse to exhibit natural behaviours such as foraging, nesting, hiding, resting, playing, exercising, and grooming. The more space and complexity in their living environment, the better. Multiple levels connected by ramps or ladders can provide more space and interest for your mouse.

In terms of the type of enclosure, an aquarium or wire cage with proper substrate is a good choice. If you opt for an aquarium, choose one that is at least 10 gallons (38 litres) in size and has a mesh lid to prevent escape. For one to three mice, a bigger aquarium is necessary—a minimum of 15 gallons (58 litres) for four to five mice, and 20 gallons (78 litres) for five to six mice. However, bigger is always better for any mouse, so get the largest aquarium that will fit in your home.

If you choose a wire cage, ensure it is at least 24 by 12 inches (61 by 30 centimetres) in size, with no more than a quarter-inch between wires to prevent escape. The cage floor should be solid, as wire mesh flooring can damage the feet and legs of mice. Additionally, make sure the cage has wire mesh on top for good ventilation.

For substrate, use shredded paper that does not contain ink. A few centimetres of substrate is adequate. Avoid using materials such as cotton wool, fine sawdust, wood shavings, or fragrant and coloured materials, as these can be harmful if ingested. Bedding material should be absorbent to soak up moisture from urine and faeces. Commercially available paper-based bedding is a good option, as it is not dusty and is digestible if eaten.

Feeding: a combination of commercial food and treats

A combination of commercial food and treats is the best diet for a pet mouse. Pellets and seeds are sold in pet stores specifically for mice. Commercial food is a good option as it contains all the nutrition that your mouse needs to be healthy. However, treats can be given occasionally to add variety to their diet.

Mice are omnivores, so they eat both animal and plant materials. They need a protein level of at least 16% and a fat content of 4-5%. A tablespoon of pellets or seeds per mouse is usually enough. It is important to feed your mouse a varied and balanced diet to keep it healthy.

Some good treats for mice include fresh fruits and vegetables, such as greens, blueberries, apples, bananas, beans, berries, bok choy, broccoli, Brussel sprouts, carrots, celery, citrus fruits, endive, fresh corn, melon, parsley, peas, pears, stone fruits, and tomatoes. These treats are not only tasty for your mouse but also help to keep their teeth healthy. Rodent teeth never stop growing, so chewing on crunchy fruits and vegetables helps to prevent them from growing too long.

It is important to introduce new foods slowly and in small amounts. Observe your mouse's digestion and only continue feeding the new food if there are no negative results. Some foods that are toxic or unhealthy for pet mice include citrus fruits, chocolate, peanuts, raw meat, onions, and garlic.

Health: exercise, vet visits, and signs to watch for

Mice are resilient animals and rarely get sick, but it's important to keep an eye out for any changes in behaviour or appearance. Mice are generally afraid of people, so minimise how often you handle your mouse. When you do pick up your mouse, do so safely. Set a treat in your palm, then lay your hand flat at the bottom of its cage. When it climbs on, gently lift it up. Hold your mouse close to your lap if it is not comfortable being held.

Mice are active animals that need plenty of exercise to stay healthy. An exercise wheel is vital for any mouse's cage. However, always opt for a plastic one over a wire one. Mice can easily get trapped and injured or even killed in a wire wheel. You should also provide toys. Inexpensive toys, like cardboard rolls from paper towels and toilet paper, are safe for mice to play with.

Mice can become unwell and deteriorate very quickly, but they may only show subtle signs of being in pain or distress until it is very severe. Take your mice to a vet immediately if they show any of the following signs:

• Not eating or drinking
• Hiding away from the other mice, more than usual
• Sitting in a hunched-up position
• Ruffled or ‘starry/spiky’ fur and/or a dirty, stained or dull coat
• Reddened or sore-looking skin
• Sunken or dull-looking eyes
• Discharge from their eyes or nose
• Losing weight, or quickly putting weight on
• Urinating lots or not at all
• Chattering or clicking sound when they breathe
• Slow, irregular or fast breathing
• Very dark red or pale limbs, ears or nose
• Very hot or very cold limbs
• Fitting, twitching, tremors or shivering
• Difficulty walking, or unsteady balance
• Self-mutilation or gnawing at themselves
• Hot, swollen stomach
• Any injuries or abnormal lumps or bumps

Regular vet checks will help spot problems early and help prevent disease.

Handling: how to pick up and play with your mouse

Mice are naturally timid, skittish creatures, so it's important to be gentle and patient when handling your pet mouse. Here are some tips on how to pick up and play with your mouse safely:

• Gaining your mouse's trust: Before attempting to pick up your mouse, it's important to gain its trust. Place your hand in the mouse's cage with your palm facing up and let it explore your hand. Mice have a poor sense of sight but a strong sense of smell, so it may help to wear an old sock on your wrist for a day or two so that it smells like you, then give it to your mouse as bedding.
• Using treats: You can also use treats to gain your mouse's trust. Offer treats when your mouse approaches the cage bars, and continue until it readily comes to the bars when it sees you. Once your mouse is comfortable taking treats from your hand through the bars, offer treats with the cage door open, and then place a treat on your open hand to entice the mouse to step up.
• Picking up your mouse: Never pick up a mouse by its tail, as this can be painful and cause injuries. Instead, place one hand in front of the mouse with your palm facing up and let the mouse climb onto your palm. If it refuses, gently slide your hand underneath it. Check that the mouse is secure, then carefully lift it up.
• Holding your mouse: If you plan on holding the mouse for a brief amount of time, you can scoop it up and gently close your fingers around it. If you need to hold it for longer, grab the loose skin on the back of its neck (the scruff) to prevent it from squirming out of your grip.
• Playing with your mouse: Mice love motion, so don't be afraid to move your hands, arms, and shoulders while your pet explores. You can also provide toys for your mouse to play with, such as cardboard tubes or commercial toys from a pet store.
• Handling multiple mice: If you have more than one mouse, it's important to handle them separately to avoid any bullying or fighting.
• Keeping your mouse safe: Mice are very small and quick, so it's important to create a safe play area where they can't escape or hide in inaccessible places. You can do this by building a circle of pillows, playing with your mouse in a small space like a bathroom, or using a solid-sided puppy corral.

Bedding: what to use and how often to change it

Mice love to burrow and nest, so you'll need to provide lots of suitable bedding. The ideal bedding is dust-free, odour- and moisture-absorbing, and comfortable for your pet. Paper bedding is a good option as it's compostable, biodegradable, and lightweight, reducing fuel use. You can also use shredded paper, but make sure it's ink-free or non-toxic.

Avoid cedar or unprocessed pine shavings, as the aromatic oils can cause respiratory distress. Soft aspen shavings are dust-free and odour-free but may be less absorbent than paper and not as effective at reducing odours. Kiln-dried pine shavings (which are free from harmful aromatic oils) or eco-friendly pelleted wheat straw are also good options.

Mice need at least 2-3 inches of bedding at the bottom of their cage. This provides comfort for their feet and warmth when they nest and rest. It also facilitates burrowing and digging, which are some of a mouse's favourite activities.

Remove soiled bedding daily and change all bedding at least twice a week. Cages housing many mice or those with males (who have more fragrant urine) may need to have their bedding changed more frequently.

Frequently asked questions