Advancing experimental fish welfare: insights from the Swiss fish welfare meeting 2026

Fish are widely used in research and aquaculture, yet many aspects of their welfare remain poorly understood. Recent years have seen a shift from health and disease prevention as cornerstones of wellbeing toward concepts of welfare that include behavior, affective states, cumulative lifetime experiences, and positive welfare. Current challenges relate to the taxonomic diversity of fishes, the dominance of zebrafish as model species, and the translation of welfare concepts across experimental, applied, and industrial settings. Knowledge gaps remain regarding welfare assessment, environmental enrichment, euthanasia, pain management, and the implementation of evidence-based refinement measures. Here we summarize the outcomes of the Swiss Fish Welfare Symposium 2026, which brought together researchers, caretakers, veterinarians, regulators, and industry. Participants identified drivers of change such as a Culture of Care, improved knowledge exchange, and incentive structures to reward refinement. Presentations emphasized the need for welfare research under realistic husbandry conditions, the development of cumulative and species-specific welfare assessment tools, and the generation of evidence for housing, enrichment, analgesia, euthanasia, and rehoming practices. Speakers stressed that recommendations developed under idealized conditions often fail to reflect the practical realities of research facilities and aquaculture systems. The symposium revealed a research field in transition from compliance-based approaches toward a vision of welfare that encompasses both animal and human well-being. Participants identified collaboration, systematic use of existing welfare data, and research beyond zebrafish as critical priorities. More broadly, discussions highlighted the need to bridge gaps between fundamental research, regulation, husbandry practice, and industry to achieve evidence-based and implementable improvements in fish welfare.