Laboratory Mouse Housing and Social Welfare

Mice are by far the most commonly used laboratory animals globally. Their social housing needs are well established but not always met in standard research facilities.

Key Facts

Mice account for over 60% of all animals used in biomedical research worldwide
Mice are highly social and experience significant stress when housed alone
Single housing increases stress hormones, reduces immune function, and alters research results
The EU requires social housing for mice unless scientific justification for isolation exists
Enrichment including nesting material, hiding places, and gnawing material improves welfare significantly
Group housing of male mice can lead to fighting, requiring careful management to prevent injury

Welfare Considerations

Mouse welfare in research settings is directly relevant to both ethical obligations and research quality. Social isolation causes measurable physiological changes in mice that can confound experimental results, creating an alignment between welfare and scientific validity. Providing social housing, appropriate enrichment, and positive handling through tunnel training are practical, evidence-based interventions that most facilities can implement with minimal cost.

What You Can Do

Support advocacy for mandatory social housing standards in research mouse facilities
Encourage research institutions to publish their 3Rs implementation practices
Donate to development of humane mouse handling techniques including tunnel training
Advocate for replacing and reducing mouse use through investment in alternative methods
Support transparency requirements for institutional animal care and use committees