The methodology of pain research in zebrafish has direct welfare implications both for the fish used in experiments and for the broader understanding of fish sentience.
Zebrafish pain research methodology has both direct and indirect welfare implications. Directly, fish used in pain induction experiments experience the suffering being studied — the 3Rs require minimizing this through validated protocols with the smallest effective sample size and appropriate analgesia in recovery groups. Indirectly, the quality of zebrafish pain research determines the evidence base for regulatory protection of fish more broadly. Well-designed, reproducible research strengthens the scientific foundation for welfare-based fish protection. The field has matured substantially in the past decade, providing a solid evidence base for regulatory updating.