Rainbow trout are the second most farmed finfish in Europe, with welfare challenges throughout production that are receiving increasing scientific scrutiny.
Rainbow trout in aquaculture face welfare challenges including chronic crowding stress, handling during grading and harvesting, and slaughter methods of variable efficacy. Their high sensitivity to water quality means oxygen depletion during crowding events can cause mass suffocation. Evidence of their cognitive abilities and stress responses supports investment in welfare improvements across all stages of production. Welfare certification schemes for trout remain less developed than for salmon.