Laboratory mice are used in over 100 million experiments annually — welfare improvements in housing, enrichment, and procedures can significantly improve their experience.
Laboratory mouse welfare deserves serious attention given the extraordinary number of individuals involved. Standard cage sizes in many facilities are designed for management convenience rather than mouse behavioral needs — mice cannot express normal locomotion, exploratory, and social behavior in small, barren cages. The welfare improvements available are well-documented: larger, enriched cages with nesting material, tunnels, and social grouping; gentle tunnel or cup handling instead of tail lifting; and social housing as the default rather than the exception. These improvements reduce stress-induced confounds in research outcomes as well as improving mouse welfare — making them both ethically motivated and scientifically beneficial.