Mouse Care Guide
Mus musculus domesticus
Pet mice are notorious escape artists — a gap barely wide enough to fit a pencil is often enough for an adult mouse to squeeze through, which makes cage security one of the first things to get right.
Lifespan
1.5-3 years
Adult size
Roughly 7-10cm body length plus a similar-length tail
Diet
Mouse-specific pellet or seed mix, small fresh vegetable portions
Temperament
Social, active, generally easy to tame with gentle handling
Housing
Secure, fine-mesh or solid-walled enclosure; larger for groups
Legal notes
No special permits typically required for pet mice in Canada
Domestic mice are small, social rodents with a much shorter lifespan than most other pocket pets, which is worth setting expectations around before bringing one home, especially with kids. Their small size also makes them expert escape artists, so cage security matters as much as space or enrichment.
Housing & cage security
- Use an enclosure with fine wire mesh (bar spacing no wider than about 6mm/0.25in) or solid walls — mice can squeeze through surprisingly small gaps
- Provide a secure, tight-fitting lid, since mice are proficient climbers and jumpers as well as escape artists
- Line the enclosure with several inches of paper-based or aspen bedding for burrowing
- Avoid cedar and pine shavings, which are linked to respiratory irritation in small rodents
- Include hides, tubes, and nesting material so mice can retreat and build nests
Diet & feeding
- Feed a commercial mouse-specific pellet or seed mix rather than a generic small-rodent blend
- Offer small portions of fresh vegetables a few times a week
- Avoid high-sugar or high-fat treats, which mice are prone to overeating
- Provide constant access to fresh water via a sipper bottle
Enrichment & handling
- Provide an exercise wheel (solid running surface) since mice are highly active, especially at night
- Offer chew-safe items to help manage continuously growing teeth
- Handle gently and consistently from a young age to build trust — mice can be skittish if handling is inconsistent
- Support the body fully when picking up; avoid grabbing by the tail alone
Health & common problems
- Respiratory infections: relatively common in mice, especially with poor ventilation or ammonia buildup from infrequent cleaning
- Tumors: not uncommon in older pet mice; watch for unusual lumps
- Overgrown teeth: provide regular chew opportunities to prevent this
- Short lifespan overall: most mice live only 1.5-3 years, which owners, especially families with children, should plan for emotionally in advance
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Frequently asked questions
Typically 1.5-3 years, considerably shorter than many other small pets, which is worth keeping in mind before bringing one home, especially for families with young children.
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Social housing