Slaughter is the final welfare moment for farmed pigs, and the method of stunning and killing significantly affects whether animals experience fear and pain during the process.
Death in a slaughterhouse should be the final moment a farmed animal experiences, and how that moment is managed matters enormously. CO2 stunning, used in the majority of commercial pig slaughter in the EU and UK, causes documented distress during the induction phase when pigs react aversively to the gas before losing consciousness. This reaction includes escape attempts, vocalization, and physiological stress responses - indicating the animals are suffering during induction. Welfare-superior alternatives exist: gas mixtures using argon or nitrogen cause more rapid unconsciousness without the CO2 aversion response. The economic cost of switching is real but modest relative to the scale of welfare improvement across millions of animals.