Farm Animal Welfare

Pig CO2 Stunning Science

CO2 stunning of pigs at slaughter remains the most common industrial method but causes documented aversion and distress before unconsciousness, driving research into alternatives.

Key Facts

CO2 causes aversion responses and distress in pigs before inducing unconsciousness
High concentrations cause faster unconsciousness but greater prior distress
Argon and nitrogen gases cause less aversion than CO2 in pig stunning
EFSA and AHAW panels have reviewed and raised concerns about CO2 stunning welfare
Some slaughter plants have adopted non-CO2 inert gas systems for improved welfare

Welfare Considerations

CO2 stunning subjects millions of pigs annually to a distressing experience before the onset of unconsciousness. While alternatives exist and are being adopted in some facilities, industry-wide transition is slow. Consumer and regulatory pressure is needed to accelerate adoption of more humane alternatives.

What You Can Do

Support welfare labelling that includes slaughter method information
Learn about alternative stunning methods and their welfare advantages over CO2
Advocate for regulatory review of CO2 stunning requirements in your country