An HSUS Report: The Welfare of Birds at Slaughter

The customary slaughter method of birds killed for human consumption involves the stunning of several live birds at one time using electrical water baths supplied with constant voltages. The birds are hung upside-down on shackles prior to conveyance through the electrified bath. This system, which is used globally, is increasingly under scrutiny as research suggests that it can be both inhumane and ineffective. Scientists have demonstrated that handling, inversion, and shackling are traumatic and stressful to birds and that shackling itself may be painful. In some cases, birds may also receive painful pre-stun electric shocks. There is growing evidence that the existing electrical water-bath stunner settings, including those used in U.S. slaughter plants, may not render birds immediately unconscious. Further, birds may miss the stunner completely and remain conscious when their throats are cut and possibly when they reach the scald vat. Since the existing, constant voltage, electrical water-bath systems that involve stunning several birds simultaneously are increasingly considered inhumane, alternative technologies that use gas mixtures to render birds unconscious have been developed to improve animal welfare. To date, the most effective and least aversive method of stunning birds prior to slaughter is Controlled Atmosphere Killing (CAK), which rapidly and efficiently gasses birds while they are in transport crates.