The review of new scientific data on some existing equipment meeting European Union (EU) technical standards under EU regulation (EC) No 1099/2009 concluded some "birds were not rendered immediately unconscious by the intervention". It added that when this happens, birds suffer "pain, distress and suffering".
It added the data "failed to demonstrate absence of pain and suffering until the onset of unconsciousness". And it said: "The minimum duration of unconsciousness was too short to ensure unconsciousness until death by bleeding."
EFSA said: "The complexity of multiple bird electrical waterbath stunning systems used in poultry slaughterhouses, such as the one assessed here, are not conducive to maintaining good animal welfare and, therefore, alternatives should be developed/implemented."
However, it did not recommend changing EU rules. These say that for 200 hertz (Hz) stunning systems, chickens should be exposed to 100 milliampere (mA); and for systems from 200 to 400 Hz, it should be 150 mA. For head-only stunning it should be 240 mA.
The regulation insists that livestock "shall only be killed after stunning… [and] the loss of consciousness and sensibility shall be maintained until the death of the animal [or bird]". The systems assessed in the report used 15 seconds of shocks of 104mA, voltage of 125.86V and a frequency of 589.78 Hz. But it said this was not "long enough to prevent recovery of consciousness before neck cutting or during bleeding".