An Investigation of a Potential Method for the Humane Taking of Certain Whales and Seals Used for Food

摘要

Gas injection was investigated to determine whether such a technique deserves consideration as a more humane and less wasteful method of taking marine mammals. In experiments with swine the authors studied the time course of unconsciousness and brain death after injecting carbon dioxide or air. The electroencephalogram (EEG), electromyogram (EMG), electrocardiogram (ECG), the auditory evoked potential (EP) and the corneal reflex were used to monitor the state of awareness. High pressure air injections produced EEG and EP changes consistent with loss of consciousness in as little as seven seconds. Injections in muscles of the rear limb or back were just as effective as in the thorax or abdomen. Rapid death can be produced by gas injection. Although gas injection can kill rapidly and therefore might be more humane than the more prolonged methods currently used, a number of technical problems, especially rapid injection of large amounts of gas, would have to be overcome before the method could be tested in marine mammals. Explosives that also produce gas probably offer more promise than compressed gas alone. The experiments presented here, using anesthetized swine with physiological monitoring serve as a model for testing the potential humaneness of any proposed technique.