Rainbow trout are one of the most commonly farmed fish species globally, with welfare standards that have improved but still fall short of what evidence on trout pain and stress demands.
Rainbow trout welfare has advanced from complete indifference to increasing scientific and regulatory attention, but gaps between evidence and practice remain significant. Trout are among the best-studied fish species for pain and stress responses, with research clearly demonstrating their capacity for aversive experience. High stocking densities, routine handling without analgesia, and inadequate slaughter methods impose unnecessary suffering at enormous scale. Welfare certification for trout is an achievable and meaningful improvement that some markets are beginning to demand. Consumer awareness of trout welfare issues can accelerate the regulatory and industry changes needed.