Rainbow trout farming is a major aquaculture sector globally, producing over 800,000 tonnes annually. Despite trout's cognitive complexity and clear pain sensitivity, welfare standards in trout farming remain poorly developed.
Trout farming welfare suffers from the same invisibility problem as other farmed fish - out of sight, largely out of mind. Yet trout are cognitively sophisticated animals with demonstrable pain responses, individual personalities, and social behavior that is systematically suppressed in commercial conditions. High stocking densities create chronic stress that manifests in elevated cortisol levels, fin damage from fighting, and disease susceptibility. Slaughter without stunning - still practiced in much of the industry - causes prolonged suffering during death. The welfare gap between what trout experience in commercial production and what is achievable with better management is large, and largely a matter of economic priority rather than technical impossibility.