Rainbow trout are among the most widely farmed fish globally, with significant welfare challenges around stocking density, aggression, slaughter methods, and the stress of water quality fluctuations in intensive production.
Rainbow trout welfare is more advanced in research and certification than most aquaculture species — the RSPCA Assured trout standard covers stocking density, slaughter, and water quality requirements. However, uncertified trout production remains dominant and welfare conditions are highly variable. Consumer certification demand and retailer sourcing requirements are the primary drivers of welfare improvement in the trout sector.