Rainbow trout slaughter methods significantly affect welfare. Effective stunning before slaughter is essential to prevent conscious suffering at the point of death.
Trout slaughter has historically involved methods causing prolonged suffering, particularly CO2 narcosis which triggers escape behaviour and stress responses before unconsciousness. Electrical water bath stunning, when correctly calibrated for species and water conductivity, produces immediate unconsciousness. Combination stunning with electrical stun followed by immediate spiking (pithing) is the gold standard. Welfare at slaughter is a key factor in choosing responsibly produced trout.