Rainbow trout are one of the most widely farmed fish species globally, but welfare standards in trout production lag significantly behind those for other farmed species.
Rainbow trout occupy a somewhat awkward position in welfare discussions — their capacity for pain experience is supported by substantial scientific evidence, yet they receive far less regulatory attention than mammals or birds. The scale of trout production means welfare improvements would benefit enormous numbers of fish. The primary welfare issues in intensive trout farming are crowding stress, handling stress, inadequate stunning at slaughter, and the cumulative effects of chronic physiological stress on health and lifespan. The good news is that welfare-positive interventions — lower stocking densities, flow-through tank systems providing adequate oxygenation, and effective pre-slaughter stunning — are technically feasible and some producers are already adopting them.