Time to loss of somatosensory evoked potentials and onset of changes in the spontaneous electroencephalogram of turkeys during gas stunning.
The times to the loss of somatosensory evoked potentials (SEPs) and the onset of suppressed and isoelectric electroencephalogram (EEG) were investigated in turkeys as they were stunned with gas mixtures consisting of one of three mixtures: (A) 30 per cent carbon dioxide and 60 per cent argon in air (2 per cent residual oxygen and 8 per cent residual nitrogen); (B) 90 per cent argon in air (2 per cent residual oxygen and 8 per cent residual nitrogen); (C) 65 per cent carbon dioxide in air (7 per cent residual oxygen and 28 per cent residual nitrogen). The time to the loss of SEPs, EEG suppression and the onset of an isoelectric EEG, respectively, were 22, 16 and 35 seconds in mixture A, 44, 41 and 101 seconds in mixture B, and 15, 15 and 67 seconds in mixture C. Stunning turkeys with mixture A or B would be suitable under commercial conditions. Mixture C, containing 65 per cent carbon dioxide in air, is considered on humanitarian grounds to be unacceptable for stunning turkeys owing to the pungency of the carbon dioxide at this concentration.
Raj
M
M
Division of Food Animal Science, School of Veterinary Science, University of Bristol, Langford.
Gregory
N G
NG
D000003:Abattoirs; D000388:Air / Q000032:analysis; D000818:Animals; D001128:Argon / Q000633:toxicity; D002245:Carbon Dioxide / Q000633:toxicity; D004562:Electrocardiography / Q000187:drug effects / Q000662:veterinary*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D005740:Gases / Q000633:toxicity*; D009584:Nitrogen / Q000633:toxicity; D010100:Oxygen / Q000633:toxicity; D013997:Time Factors; D014422:Turkeys
D005740:Gases; D002245:Carbon Dioxide; D001128:Argon; D009584:Nitrogen; D010100:Oxygen