Poultry slaughter involves welfare risks during catching, shackling, stunning, and killing that require specific standards and monitoring to minimize suffering.
Chicken slaughter welfare is compromised by the standard electrical water bath stunning system that requires conscious birds to be hung inverted by their legs, experiencing the pain of shackling and the fear of inversion and hanging before stunning. Birds that miss the water bath receive no stun and may be killed while fully conscious. Controlled atmosphere systems that render birds insensible before shackling eliminate the pre-stun welfare cost and ensure more uniform insensibility. The scale of chicken slaughter means that small percentage improvements in welfare standards have enormous absolute welfare impacts across billions of individual animals. Consumer and retailer demand for higher welfare standards creates market pressure for system improvements that legislation has been slow to mandate.