Caring for mice

Mice are omnivores, and will eat a variety of foods including seeds, fruits, vegetables and grains. High quality commercial mouse pellets should be provided at all times. In addition, healthy fresh fruits and vegetables should be provided (such as apples, pears, banana, melons, broccoli, cabbage, carrots, celery, parsley, beans and peas). Mice need food available at all times.

Mice also need free access to clean, fresh water at all times. A good option is a dripper-type bottle attached to the side of their cage with regularly replaced fresh water. These are less likely to become soiled than water bowls and can be filled up without having to open the mouse house and disturb the mice.

Enrichment ideas: Hiding and scattering portions of your mice’s daily food throughout their enclosure can encourage foraging behaviour and can be an enriching activity.

The more space you can provide for your mice, the better! Sturdy plastic enclosures can be a good choice as they can be cleaned without worrying about cracking or rusting. It is important that the enclosure's flooring is solid. Wire floors can cause a painful condition in mice called ‘bumblefoot’ where their feet swell and become inflamed and infected. Make sure the enclosure you choose is also made from materials impervious to chewing, as mice love to chew and can be fantastic escape artists.

It is best to position the enclosure in a quiet, undisturbed area away from the main activity of the home and out of direct sunlight. Mice are particularly susceptible to heat and can experience heat exhaustion when temperatures exceed 30°C.

Line the enclosure with an absorbent substrate, such as wood chippings (not pine or cedar) or recycled paper kitty litter. Mice are sensitive to high ammonia (produced by mouse urine) levels in the air. It is important to clean the enclosure and replace substrate regularly to keep ammonia levels down.

You will also need to provide your mice with nesting materials, such as shredded paper, and a nest box, such as igloos or cardboard boxes. Mice love a place to hide, so it is best to provide multiple shelters and boxes. Add multiple levels and exciting things to their enclosure to climb and explore. This can include ramps, platforms, boxes to climbs, and rope ladders. You can pick these up at pet stores or get creative and make your own.

Mice are very social and it is important that they are housed with another mouse as a companion. Ideally, the companion should be a same-sexed littermate (sibling) or a same-sexed mouse of a similar age. All female groups tend to get on better than all male groups, as unfamiliar males will tend to fight. Mice are prolific breeders and therefore same-sex groups are recommended to prevent unwanted pregnancies.

A healthy mouse should have a healthy coat (e.g. no patches of missing fur), clear bright eyes, well-formed poo, healthy feet without sores and are active and curious.

When mice get sick, they can get very unwell very quickly. They often only show subtle signs of being in pain or distress or that they are suffering, until it is very severe.

Things to watch out for include:

• Not eating or drinking
• Lethargy
• Diarrhoea
• Dull coat or hair loss
• Discharge from eyes/dull eye colour
• Discharge from nostrils
• Abnormal breathing
• Weak hind legs
• Scratching excessively
• Weight loss
• Injuries
• Abnormal lumps or bumps

Please consult your veterinarian immediately if you notice any of these signs of illness.

Mice are active, intelligent and curious animals that require exercise and mental stimulation for optimal health. They are excellent climbers, jumpers, and love to investigate, forage and explore their enclosures and toys.

Some of the types of toys that are great to encourage normal mice behaviours include:

• Climbing toys such a ladders, ropes, branches or tubes.
• Tunnels made of PVC
• Chew toys made from safe ingredients such as non-treated wood and cardboard tubes.
• Soft paper or tissues, mice love to shred!
• Toys they can push or carry such as plastic balls with bells in, just make sure they aren’t small enough for the mouse to swallow.
• Toys that encourage natural foraging for food such as cardboard tubes or origami tubes.

Visit the SPCA Kids’ Education Portal (www.spca.nz/kids) for more information on caring for your companion mice, including more enrichment ideas and helpful videos!