Scientific Opinion on the electrical requirements for waterbath stunning equipment applicable for poultry
The Commission requested that EFSA review relevant new scientific references on electrical stunning of poultry and to recommend, if necessary, new electrical requirements applicable for waterbath stunning equipment. A systematic literature review was conducted to determine those electrical parameters that would deliver an effective stun so that birds would be rendered unconscious and insensible until death. Inspection data from slaughterhouse inspections conducted both in Member States in and non-Member States were included. Many of the published studies did not allow a comprehensive analysis due to different study designs and incomplete data. There are few observational studies in abattoirs to determine the numbers of birds that are effectively stunned, however, the inspection data from the Food and Veterinary Office (FVO) did not identify major problems but, for practical reasons, they used non-EEG (electro-encephalogram) methods to ascertain the effectiveness of a stun. At the present time, an EEG is the most reliable indicator of unconsciousness and insensibility. Clinical somatosensory indicators are not as reliable. The aim of a stunning system is to achieve a 100% effective stun, and the most effective electrical parameters in use can achieve an effectiveness of up to 96% as measured using EEG ascertainment methods (100% were reported as unconscious using non-EEG methods). It is recommended that the Regulation should indicate minimum current for each bird, frequency and current type as well as the wave characteristics - duty cycle and waveform. There should be better surveillance and monitoring of the electrical parameters in use at abattoirs and, in addition, methods that allow the accurate measurement of actual electrical current flowing through each bird should be further developed. Research on effective stunning should be validated by the measurement of EEG activity and related to clinical measures that are easier to use in practice.