An evaluation of humane gas stunning methods for turkeys.

Spontaneous electroencephalograms (EEG) and somatosensory evoked potentials (SEPS) were recorded in turkeys while they were kept in an atmosphere of either 49 or 86 per cent carbon dioxide in air. The time to the loss of SEPS was not related to the concentration of carbon dioxide, but the time to the onset of an isoelectric EEG was shorter at the higher concentration of carbon dioxide. In comparison with other gas stunning methods it was considered that stunning with these high concentrations of carbon dioxide would not have any welfare advantages over stunning in argon with 2 per cent residual oxygen or in a mixture of 30 per cent carbon dioxide and 60 per cent argon in air.