Ensuring pigs are effectively stunned before slaughter is the most critical welfare requirement at end of life, yet stunning failures remain a welfare concern.
The welfare of pigs at slaughter depends entirely on the effectiveness of stunning before killing. An animal that is improperly stunned and regains consciousness before or during slaughter experiences one of the most acute and severe welfare failures possible. The widespread use of high-concentration CO2 stunning means that even 'effective' stunning involves a period of aversive experience before unconsciousness. Developing and adopting more humane stunning methods combined with robust monitoring is the highest welfare priority at slaughter.