The space and social housing conditions provided to non-human primates in research are critical welfare determinants, with minimum regulatory standards often falling well below what welfare science recommends.
Space and social housing represent two of the most fundamental welfare determinants for laboratory primates. Minimum cage size regulations were established decades ago and reflect what was considered technically feasible rather than what welfare science shows primates need. The difference between regulatory minimum space and welfare-optimal space is enormous — wild primates range over areas orders of magnitude larger than any laboratory cage. Social housing addresses the equally fundamental need for social interaction in highly social species. The welfare cost of individual housing — required by some research designs — is real and must be carefully justified. Institutions that go beyond minimum standards to provide larger spaces and priority social housing demonstrate that regulatory floors are not welfare ceilings.