Farmed Pig: Slaughter Welfare CO2 Alternative Developments

CO2 gas stunning for pigs causes detectable distress before unconsciousness, and developing more humane alternatives is a major focus of slaughter welfare research.

Key Facts

CO2 stunning is used for over 90% of commercially slaughtered pigs in the UK and EU
Pigs exposed to high CO2 concentrations show aversion behaviour including attempting to escape the gondola
The aversive phase before unconsciousness is estimated at 30-60 seconds depending on concentration
Low-atmosphere pressure stunning (LAPS) is an alternative that may be less aversive
Inert gas mixtures including argon and nitrogen may reduce the aversive phase
EFSA has concluded that CO2 stunning is aversive and called for development of more humane alternatives

Welfare Considerations

CO2 stunning represents a significant welfare compromise accepted as an industry norm despite clear scientific evidence that the 30-60 seconds before unconsciousness involves genuine aversive experience. Pigs display panic behaviour, attempt to escape, and show physiological stress responses during this period. The scale of pig slaughter means that this preventable distress is experienced by hundreds of millions of animals annually in Europe alone. Alternative methods are being developed and should be prioritised over economic arguments for maintaining CO2 stunning. The welfare imperative for slaughter is unconsciousness before any noxious procedure - CO2 stunning fails this standard for the pre-unconscious phase.

What You Can Do

Support research funding and regulatory attention for more humane pig stunning alternatives
Advocate for EFSA recommendations calling for development of CO2 alternatives to be actioned
Choose pork from producers investing in welfare-improving slaughter technology
Support campaigns raising public and industry awareness of CO2 slaughter welfare concerns
Reduce pork consumption to reduce the scale of conventional CO2 slaughter operations