Most people look up pet mice care when they’re deciding whether mice are the right fit, or when something feels slightly “off” at home: a new sneeze, a sudden skittishness, a smell that won’t shift, or a cage that never seems quite big enough. With animals this small, small problems can move quickly.
Good mouse care is mostly quiet routine: steady warmth, clean air, stable social groups, and food that doesn’t invite picky eating. The details matter because mice live fast—short lives, quick metabolisms, and little tolerance for stale bedding and poor ventilation.1, 2
Choosing the right mice
Types of pet mice
Most pet mice in Australia are “fancy mice” (domestic mice bred for temperament and colour). Coat types vary—satin, long-haired, and hairless lines exist—but the daily needs are broadly the same: safe housing, stable companionship, and gentle handling.3
How to pick healthy mice
A healthy mouse tends to look and move like a small, alert animal built for constant scouting: bright eyes, a clean nose, tidy coat, and an interest in what’s happening around it.4
- Look for: clear eyes, dry nose, even breathing, smooth coat, steady movement, and normal curiosity.
- Avoid: sneezing, clicking/wheezing, crusty eyes or nose, hunched posture, diarrhoea, patchy fur, or constant scratching.
- Choose stable groups: whenever possible, take a pair or small group that has already been living together (often siblings). Changing a group later can trigger fighting.2
Housing and environment
What a good mouse enclosure needs
Mice are agile climbers and persistent chewers, and they urinate frequently. That means the enclosure needs two things at once: secure construction and excellent ventilation. Wire-sided cages with a solid base generally provide the best airflow; solid-sided tubs and aquariums tend to trap ammonia and humidity, which can irritate airways.5
Skip wire floors. A solid base with deep bedding protects feet from injury and irritation (including pododermatitis/“bumblefoot”).5
Space, layout, and where to put the cage
There aren’t strong evidence-based “perfect” cage size rules for companion mice, so the practical target is simple: as large as you can comfortably maintain, with multiple levels and plenty of hides. More space and complexity gives mice more choice—where to sleep, where to forage, where to retreat—and that reduces friction within the group.5
Place the enclosure off the floor, away from direct sun, draughts, heaters, and air conditioners. A quieter room you use often works well, but remember mice are most active at night, which can make bedrooms a poor match.5
Bedding, nesting, and enrichment
Mice need bedding they can dig into and separate nesting material they can gather and shape. Avoid fluffy, stringy nesting fibres that can tangle around limbs or be swallowed, and avoid fragranced or dyed products that may irritate sensitive airways.3, 6
Enrichment doesn’t need to be fancy. It needs to be changeable: tunnels, cardboard to shred, climbing branches, and scattered feeding to encourage foraging. Chewing and hiding are especially important behaviours in mouse groups.2
Diet and water
What to feed pet mice day to day
Base the diet on a complete commercial mouse food (often sold as “nuggets” or blocks) so mice can’t pick out only the tasty bits and miss essential nutrients. Add small amounts of fresh produce as part of the daily ration, not on top of it.7
- Everyday base: commercial mouse nuggets/blocks.7
- Fresh extras (small amounts): pieces of carrot, broccoli, apple and similar produce.8
- Foraging: scatter some of the daily allowance through the enclosure so mice spend time searching and handling food.7
Foods to avoid (and why)
Some foods are outright unsafe, and others are simply trouble in a small digestive system (diarrhoea and dehydration can follow quickly). Avoid known toxic items like grapes/raisins and rhubarb. Onion is also best avoided, and very sugary or fatty foods should stay firmly in “rare treat” territory.7
Water: constant, clean, checked daily
Mice should have constant access to clean water. A bottle with a metal sipper tube usually stays cleaner than a bowl, but either way it needs daily checks for blockages, leaks, and contamination.7, 8
Social needs and everyday handling
Group housing: what works (and what doesn’t)
Mice are social animals and usually do best with mouse company, not alone. Stable, single-sex groups—especially groups of females—tend to be the simplest arrangement for most homes.1, 2
- Generally best: a small group of females that has grown up together.1, 2
- Avoid: housing intact adult males together (fighting is common).1, 2
- Avoid: mixing males and females unless you have firm veterinary guidance and desexing is involved—unplanned litters happen quickly.1
- Don’t house rats and mice together: they may be incompatible and can compete for resources.6, 8
Handling without stress
Mice can learn to tolerate and even seek out gentle human contact, but the process is slow and physical safety comes first. Let them approach your hands. Scoop and support their whole body. Don’t lift by the tail. Frequent, calm handling from a young age helps.1
Children should always be closely supervised. Mice are fragile, and a sudden squeeze or drop can cause serious injury.1
Health, lifespan, and when to see a vet
How long pet mice live
Many pet mice live around 1.5–2.5 years, though shorter and longer lifespans are seen. Their short lifespan isn’t a sign of “poor care” by default—it’s normal mouse biology—but it does mean age-related problems can arrive early compared with other pets.9
Common health problems to watch for
Respiratory disease is a recurring theme in mouse care, and the cage environment plays a big role. Poor ventilation and dirty bedding allow ammonia to build up, irritating airways and contributing to respiratory disease complex.6
- Red flags: sneezing, noisy breathing, breathing with effort, lethargy, reduced appetite, weight loss, crusty eyes/nose, persistent scratching, or wounds from fighting.
If you notice any of these, contact a vet experienced with small mammals. Mice can deteriorate quickly, and “wait and see” often costs time you don’t have.8
Preventative care that makes the biggest difference
- Air quality: prioritise ventilation and frequent removal of soiled bedding to limit ammonia build-up.5, 6
- Stable groups: keep social groups steady; avoid adding or removing mice where possible.2
- Regular observation: spend a minute watching them each day—movement, breathing, coat condition, and appetite changes are often the earliest clues.
Cleaning and maintenance
A realistic cleaning rhythm
Cleaning isn’t just about smell. It’s about air. Mice produce a lot of urine, and ammonia builds quickly in enclosed spaces, especially in poorly ventilated housing.5, 6
- Daily: remove visibly soiled bedding, remove any stashed fresh food, and wipe obvious wet spots on solid surfaces.5
- Regular deep clean: refresh bedding and wash solid surfaces often enough that the enclosure never develops a strong ammonia smell. Frequency depends on cage size, ventilation, and number of mice.
Leave a small amount of clean, familiar nesting material when you can. A total strip-out every time can make the enclosure smell “new” in a way that encourages more marking, which can make odour control harder, not easier.
Fun facts (the kind that help you care better)
Small animal, sharp senses
Mice live in a world of fine sound and quick movement. Their hearing is highly sensitive, and they’re built for climbing, jumping, and rapid shelter-seeking, which is why they do best with multiple hides and a calm, predictable home environment.4
Final thoughts
Pet mice do well when their world stays steady: familiar cage-mates, clean air, safe hiding places, and a diet that doesn’t invite selective eating. The reward is subtle and daily—small nocturnal routines, careful foraging, brief bursts of athletic climbing—seen up close, in a space you’ve shaped to suit an animal that has been doing these behaviours for a very long time.
References
- RSPCA Australia – Caring for pet mice
- RSPCA Knowledgebase – What company do my pet mice need?
- RSPCA Australia – Essential tips on housing mice
- NSW Department of Education – Animals in Schools: Mice (introduction and behaviour)
- RSPCA Knowledgebase – Where should I keep my mice?
- RSPCA Knowledgebase – How should I care for my mice?
- RSPCA (UK) – What to feed pet mice
- Agriculture Victoria – Caring for pet rats and mice
- MSD Veterinary Manual – Mice at a glance
Veterinary Advisor, Veterinarian London Area, United Kingdom