Controlled atmosphere stunning using gas mixtures offers significant welfare advantages over water bath electrical stunning for poultry, as it achieves unconsciousness without the painful electrical shock and handling stress of traditional systems.
The welfare case for CAS adoption in poultry slaughter is among the strongest available in applied animal welfare — the suffering prevented is well-documented, the alternative is available at scale, and the barrier to adoption is primarily cost rather than technical feasibility. Conscious birds inverted and shackled in water bath systems experience the fear, pain, and disorientation of the pre-stun period without any welfare mitigation. CAS systems that render birds unconscious in their transport crates eliminate this entire period of suffering. Supporting retailer and regulatory pressure for CAS transition is a high-leverage welfare action given the billions of birds affected annually.