Zebrafish are increasingly important research animals, and their welfare needs — including social housing, environmental complexity, and pain management — are becoming better understood.
Zebrafish welfare has advanced significantly in recent years, driven by their increased use in biomedical research and growing recognition of their welfare needs. As social shoaling fish, isolation — common in many research protocols — causes measurable behavioral and physiological changes. Provision of social groups, appropriate substrate, and hiding structures significantly improves welfare without affecting most research outcomes. Pain management for procedural interventions is increasingly recognized as a welfare obligation. The Three Rs framework applies fully to zebrafish, and refinement improvements are both achievable and well-documented in the scientific literature.