Fish are widely used in biomedical research yet often receive less welfare consideration than mammals. Emerging evidence of fish pain and stress demands updated standards.
The welfare of fish in research settings has historically been overlooked compared to mammals. Yet zebrafish and other research fish are capable of experiencing distress, and studies show they avoid noxious stimuli and show learned fear responses. Improved standards including appropriate anesthesia, enriched housing, and the three Rs framework (Replace, Reduce, Refine) should apply fully to fish research as they do to mammalian models.