Zebrafish are among the most widely used vertebrates in biomedical research, and growing evidence of their capacity for pain and stress demands improved welfare standards in their care.
Zebrafish have become a model organism for genetics, developmental biology, and disease research, but their welfare has historically received less attention than that of mice or rats. Research now confirms that zebrafish are sentient vertebrates capable of experiencing pain and stress. Welfare improvements include maintaining groups rather than isolating individuals, optimizing tank conditions, minimizing painful procedures, and using anesthesia when appropriate. Regulators in the EU and UK include zebrafish under vertebrate animal protection legislation, and the US is moving in the same direction.