Pig Slaughter Welfare: CO2 Stunning and Alternatives

CO2 stunning for pigs is widely used but causes significant aversive experiences during induction - alternatives may offer improved welfare outcomes.

Key Facts

CO2 stunning is used in the majority of pig slaughterhouses globally
Pigs show strong aversive responses to CO2 including desperate escape attempts
High CO2 concentrations cause intense distress before unconsciousness (45-60 seconds exposure)
Lower CO2 concentrations or noble gas alternatives (argon, nitrogen) may reduce aversion
Electrical stunning is an alternative but carries risks of failed stunning if not applied correctly
Animal welfare scientists have identified CO2 stunning as a priority welfare concern for pigs

Welfare Considerations

CO2 stunning welfare represents a case where a widely adopted industry practice has been identified as causing significant preventable suffering. The aversive experience during CO2 induction - where pigs show behavioral distress for 30-60 seconds before unconsciousness - is acknowledged by welfare scientists and the industry, yet economic and logistical factors have slowed transition to less aversive alternatives. The welfare cost at population scale is enormous given the billions of pigs slaughtered annually. Consumer awareness and advocacy can create pressure for accelerated transition to more humane stunning approaches.

What You Can Do

Support industry and regulatory efforts to replace CO2 stunning with less aversive alternatives
Engage with food companies about their stunning method requirements from pig suppliers
Advocate for mandatory timeline for CO2 stunning phase-out in pig slaughterhouses
Reduce pork consumption to decrease the scale of slaughter welfare impacts
Support research into novel stunning methods that minimize pre-slaughter aversion
Choose pork certified to higher welfare standards that specify humane slaughter methods