Pig Slaughter Welfare and Stunning Methods

The welfare of pigs in the minutes before and during slaughter is critical. CO2 stunning - the most common method - is highly aversive, and industry transition to alternatives is underway.

Key Facts

CO2 stunning of pigs causes aversion - pigs struggle and show distress responses before losing consciousness
Around 70% of UK pigs are stunned using CO2 gas before slaughter
Electrical head-only stunning renders pigs insensible instantly but requires accurate electrode placement
Electrical head-to-back stunning is more reliable and is used in some UK facilities
High CO2 concentrations cause 30-60 seconds of aversion before unconsciousness in research settings
The Humane Slaughter Association advocates for transition away from CO2 to electrical stunning

Welfare Considerations

CO2 pig stunning is one of the clearest examples of an industry-standard welfare problem with an available solution. Research consistently shows that CO2 at concentrations required for slaughter is aversive - pigs show escape behaviour, vocalise, and show physiological stress responses for 30-60 seconds before losing consciousness. This is not a trivial discomfort but an acute distress event experienced by millions of pigs annually. Electrical stunning eliminates this aversive period. The transition cost is real but finite. Consumer pressure through higher-welfare certification that excludes CO2 stunning drives faster adoption than regulation alone.

What You Can Do

Choose pork from producers who use electrical stunning rather than CO2
Ask your supermarket about the stunning method used in their pork supply chain
Support Humane Slaughter Association campaigns for CO2 phase-out
Advocate for regulatory reform requiring electrical stunning as the default pig slaughter method
Back research into improved electrical stunning systems that make transition more accessible