Research

Laboratory Mouse Welfare: The Most Used Research Animal

Mice account for over 95% of laboratory animals used in research; their welfare challenges are significant and often underappreciated.

Key Facts

An estimated 100 million mice are used in research globally each year
Mice are highly social animals but are often housed individually in research settings
Standard laboratory caging provides no enrichment or burrowing material
Mice have been shown to experience empathy and respond to others in pain
The US Animal Welfare Act exempts mice, rats, and birds from its protections

Welfare Considerations

Laboratory mice experience chronic stress from isolation, barren environments, bright lighting on inverted schedules, and repeated handling. Individual housing causes profound welfare harm in a species that naturally lives in groups. Simple enrichment like nesting material, shelters, and running wheels measurably improves welfare and may actually improve research outcomes by reducing stress-related confounds.

What You Can Do

Support the Animal Welfare Act amendment to include mice, rats, and birds
Advocate for enrichment requirements in laboratory animal care standards
Donate to organizations developing validated non-animal research methods
Support the 3Rs framework adoption in all publicly funded research institutions
Advocate for transparent reporting of animal use and welfare outcomes in publications