Rainbow trout are produced in massive numbers globally for both food and sport fish restocking, yet slaughter welfare standards remain inconsistent and pre-slaughter stunning is not universally applied.
Rainbow trout slaughter welfare is an area where significant unnecessary suffering persists despite available solutions. Carbon dioxide stunning causes aversive behaviour suggesting it is experienced as painful before unconsciousness. Ice slurry without prior stunning results in fish remaining conscious and distressed for many minutes. Effective electrical and percussive stunning methods that achieve rapid insensibility exist and are economically feasible. Regulatory requirements for their use in commercial trout production would eliminate millions of instances of preventable suffering per year.