Rainbow trout is among the most commonly farmed freshwater fish globally, with welfare challenges including high stocking densities, sea lice alternatives, and slaughter methods requiring ongoing improvement.
Farmed rainbow trout at high stocking densities experience chronic stress with measurable welfare impacts including immune suppression, fin damage, and abnormal behaviors. As fish with demonstrated cognitive and pain response capacities, their welfare deserves the same regulatory attention as other farmed species. Percussion stunning is effective, achievable at scale, and should be standard practice before trout slaughter.