Rainbow trout are one of the most widely farmed fish species globally, yet slaughter methods in many countries still cause significant and avoidable suffering. Improving slaughter welfare is achievable.
Slaughter is one of the highest-risk points for fish welfare. Ice slurry without prior stunning is the most common method used globally for trout and causes conscious immobilization by cold shock, followed by slow death from asphyxia and osmotic shock — a process that may take many minutes. Research demonstrates that trout show signs of stress and nociception during this process. Percussive stunning followed by gill cutting provides a welfare-acceptable alternative that requires minimal capital investment. Consumer pressure and regulatory requirements in leading producer countries are gradually driving improvement.