Lab Animal Welfare - Mouse Enrichment Standards

Current standards and research on environmental enrichment for laboratory mice, including nesting material, shelter, and social housing.

Key Facts

Laboratory mice are the most widely used research animal globally with over 100 million used annually
EU Directive 2010/63 requires environmental enrichment and social housing for mice as the default
Nesting material provision dramatically reduces stereotypies and stress indicators in laboratory mice
Shelter objects reduce anxiety in novel environment tests and improve baseline reproducibility in behavioral studies
Individually ventilated cages (IVCs) can reduce airborne disease but create high noise and vibration environments

Welfare Considerations

Laboratory mouse welfare is a high-stakes issue due to the enormous numbers involved and the welfare impact of both the research procedures themselves and the housing environment. Enrichment provision is now standard in most regulated research settings but quality and consistency varies. Improving housing conditions also improves research quality by reducing the confounding effects of chronic stress on experimental outcomes.

What You Can Do

Support the NC3Rs and RSPCA Research Animals Department advocacy for higher welfare lab standards
Engage with university animal welfare bodies to advocate for enrichment quality audits
Learn about the ARRIVE guidelines ensuring welfare is considered in study design and reporting
Support the 3Rs (Replacement, Reduction, Refinement) philosophy through charitable giving
Advocate for mandatory welfare outcome reporting in published research papers