Farm Animals

Poultry Welfare and Controlled Atmosphere Killing

Controlled atmosphere killing using low-oxygen or inert gas provides a welfare alternative to CO2 stunning for poultry slaughter with lower aversion responses.

Key Facts

Low-oxygen killing using nitrogen or argon causes unconsciousness without the aversive CO2 response
Commercial CAK systems including CAS have been implemented by some UK processors
Birds lose consciousness more rapidly under low-oxygen than under CO2
The capital cost of CAK systems is higher than CO2 but welfare is substantially improved
Some major retailers have committed to CAK as a requirement for their poultry supply chains

Welfare Considerations

Controlled atmosphere killing with low-aversion gases represents the most significant available improvement in poultry slaughter welfare. Eliminating the distress of CO2 induction for billions of birds annually would be one of the most impactful welfare improvements achievable in industrial animal agriculture. Retailer commitments driving supply chain adoption create the commercial incentive for processor investment in this welfare-positive technology.

What You Can Do

Support retailers committing to CAK requirements for their poultry supply chains
Choose poultry products from suppliers using low-aversion controlled atmosphere systems
Advocate for regulatory requirements for low-aversion CAK in poultry slaughter
Support research into optimal low-aversion CAK protocols for different poultry species
Engage with supermarket animal welfare surveys advocating for CAK requirements