Mice, rats, gerbils, and other small mammals used in biomedical research experience significant welfare challenges from housing, handling, and experimental procedures, with the 3Rs framework guiding refinement efforts.
Small mammals in research settings are often subject to welfare compromises that are habituated rather than necessary. Housing conditions below minimum environmental enrichment standards, routine tail-handling that increases anxiety, and social isolation post-surgery are examples of refinements that are technically feasible but not yet universally implemented. The 3Rs framework provides ethical direction, but institutional culture, cost pressures, and inertia slow adoption of known refinements. Welfare bodies, ethical review committees, and research funders all have roles in accelerating implementation of refinements that reduce suffering without compromising scientific validity.