Pre-slaughter stunning of poultry is legally required in most developed countries but exemptions, equipment failures, and inadequate oversight mean millions of birds are killed while conscious annually.
Stunning failures in poultry slaughter represent a significant welfare risk at the point of killing. Water bath systems that are improperly set cause only partial stunning, and birds that dodge the bath are killed while fully conscious. The scale of commercial poultry slaughter — billions of birds annually — means that even small failure rates translate to enormous numbers of birds experiencing the killing process conscious. Controlled atmosphere stunning eliminates most failure modes when correctly designed and monitored.