Field Study of Unconsciousness Monitoring in Poultry after Stunning Using Real-Time EEG Interpretation Method

Abstract

Traditionally, the Muslim’s food must be slaughtered by the Islamic way called Halal. That is, the animals must be alive at the time of slaughter and after stunning they must recover to normal position in 5 minutes. According to the animal welfare point of view, the electrical waterbath stunning is permitted before the poultry being killed in order to make the poultry unconscious during slaughtering period. This is the only condition to satisfy both the Muslim and the animal welfare regulation. During the process of slaughtering until the end of bleeding, approximately 44 second, the poultry should not be conscious during this stage. How to make sure that the poultry will not be conscious during this period according to the various electrical waterbath stunning parameter is a very challenging problem to be solved. As the clinical somatosensory sign, e.g. corneal reflect and wing flapping, may not be reliable to detect the unconsciousness, the electroencephalogram (EEG) becomes one of the most reliable methods to clarify the unconsciousness. However, unlike the laboratory condition, on the field study we cannot measure the prestunning EEG as the baseline to automatically detect the unconscious stage according to the EEG suppression. Without the need of recording the prestunning EEG, frequency-based algorithm is proposed in this paper to detect the unconsciousness. With the proposed algorithm, we can observe that trends of the EEG are shifted from lower to higher frequencies while the poultry is being recovery. Investigations on the suitable current and frequency parameters for the stunner in any animal batches are also explored. According to the preliminary results, the proposed method and criteria can be efficiently used in the real environment (field study).