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Evaluation of microwave energy as a humane stunning technique based on electroencephalography (EEG) of anaesthetised cattle

Published online by Cambridge University Press:  01 January 2023

J-L Rault*
Animal Welfare Science Centre, School of Land and Environment, University of Melbourne, Melbourne, VIC 3010, Australia
PH Hemsworth
Animal Welfare Science Centre, School of Land and Environment, University of Melbourne, Melbourne, VIC 3010, Australia
PL Cakebread
Animal Welfare Science Centre, School of Land and Environment, University of Melbourne, Melbourne, VIC 3010, Australia
DJ Mellor
Animal Welfare Science and Bioethics Centre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand
CB Johnson
Animal Welfare Science and Bioethics Centre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand
* Contact for correspondence and requests for reprints:


Humane slaughter implies that an animal experiences minimal pain and distress before it is killed. Stunning is commonly used to induce insensibility but can lead to variable results or be considered unsatisfactory by some religious groups. Microwave energy can induce insensibility in rats, and high power equipment has recently been developed for sheep and cattle. We examined the effectiveness of different settings for microwave energy delivery, power and duration, to induce insensibility based on electroencephalography (EEG) of anaesthetised cows, using the minimal anaesthesia model. All applications resulted in the appearance of seizure-like complexes in the EEG, a pattern considered incompatible with awareness. Shorter duration of application resulted in more rapid EEG changes, as quickly as 3 s. Higher power resulted in a longer duration of EEG suppression, at least 37 s and up to 162 s. Microwave energy can induce insensibility in cattle based on seizure-like complexes in the EEG.

Research Article
© 2014 Universities Federation for Animal Welfare

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