Lab Mouse Housing: Social Needs and Environmental Enrichment

The vast majority of laboratory mice are housed in ways that fail to meet their social and environmental needs. Evidence-based improvements can enhance welfare without compromising research validity.

Key Facts

Mice are highly social animals that show distress when individually housed — including elevated corticosterone
Single housing is common in research to prevent fighting or for experimental control, despite welfare costs
Group-housed mice show less anxiety, better immune function, and more stable weight — affecting experimental results
Nesting material is one of the most impactful enrichments: mice build nests rapidly and use them continuously
Standard shoebox cages provide approximately 500cm2 of floor space — insufficient for groups of 5 or more mice

Welfare Considerations

Improving laboratory mouse housing is not merely a welfare issue — it is also a scientific quality issue. Chronically stressed mice show altered physiology, behaviour, and drug responses that compromise research reproducibility. Social housing, nesting material, and cognitive enrichment produce calmer, healthier, more experimentally stable animals. The NC3Rs has published comprehensive guidance on refining mouse housing, and many of the most impactful changes cost little. Institutional culture is the main barrier to adoption.

What You Can Do

Support the NC3Rs (nc3rs.org.uk) campaign for higher housing standards in research
Advocate for institutional 3Rs committees with real authority to enforce refinement
Encourage academic institutions to publish annual reports on animal use and welfare measures
Support development of non-animal research methods through charitable donations and advocacy