Macaques are the most widely used primate in biomedical research, raising profound welfare concerns given their cognitive complexity, social nature, and capacity for psychological suffering.
Macaque welfare in research contexts is seriously compromised by the tension between research requirements and species needs. Social macaques isolated for research protocols develop behavioral pathologies — self-biting, hair pulling, stereotypic rocking — that indicate genuine psychological suffering. Invasive neurological procedures cause pain and restrict normal movement and social interaction. The scientific community increasingly recognizes that stress from poor welfare conditions compromises research quality, creating a dual imperative for improvement. Pair housing, environmental enrichment, and positive reinforcement training all represent evidence-based welfare improvements that also improve research reproducibility.