Rainbow trout is one of the most commonly farmed fish species globally, with welfare challenges including high stocking densities, fin damage, and handling stress during grading and harvest.
Rainbow trout welfare in commercial production is affected by many of the same factors as other intensively farmed fish — stocking density, water quality, handling frequency, and slaughter method. Fin damage from abrasion against crowded conspecifics or tank surfaces is both a welfare indicator and a product quality issue, creating some alignment between economic and welfare interests. Trout have been among the better-studied farmed fish in welfare terms, providing a foundation for evidence-based standards. Applying this knowledge consistently across production systems requires regulatory frameworks that move beyond minimum compliance.