Mice are used in more than 60 percent of all animal experiments globally. Improving their housing, handling, and experimental conditions has enormous welfare impact.
Laboratory mice represent the largest single category of research animals in the world, making improvements to their welfare among the highest-impact interventions in animal welfare science. Conventional housing in small barren cages denies fundamental behavioral needs including burrowing, nesting, and social interaction. Research shows that enriched housing does not compromise experimental validity and in many cases improves data quality by reducing stress-induced variability. Simple improvements — providing nesting material, using tunnel or cup handling rather than tail-grabbing, and ensuring appropriate social housing — are low-cost and significantly improve welfare outcomes for hundreds of millions of animals annually.