Controlled atmosphere killing (CAK) using inert gases or CO2 is increasingly used in poultry slaughter. Understanding the welfare differences between methods guides better standards.
Slaughter method is a critical welfare decision affecting billions of birds annually. Conventional electrical waterbath stunning requires conscious birds to be shackled upside down by their legs — a process that causes acute pain from leg injuries and severe fear — before stunning. Well-designed inert gas CAK eliminates this aversive handling step: birds lose consciousness in their transport containers without the handling, inversion, and shackling that cause pre-slaughter suffering. The welfare case for transitioning from conventional stunning to inert gas CAK is strong, with the primary remaining barrier being capital investment cost rather than welfare uncertainty.