Effect of the shooting position on the stunning of calves by captive bolt.
Captive bolt stunning frontally, occipitally and on the nape of he neck was studied in 30 veal calves. The state of consciousness was judged from the electroencephalogram (EEG) recorded via surgically pre-implanted electrodes frontally on the right side of the head. Frontal stunning on the left side of the head and occipital stunning almost certainly ensured immediate unconsciousness because delta and theta waves (tending to an iso-electric line) appeared on the EEG directly after stunning. Additionally the corneal reflex was absent. Occipital placing did not result in macroscopical damage to the cortex as did frontal stunning. Shooting witha captive bolt in the nape of the neck caused unconsciousness after mean (+/- sd) 21 +/- 6 seconds. Until then the calves were fully conscious, according to the electroencephalogram and also showed a positive corneal reflex. It is therefore suggested that for the sake of animal welfare captive bolt shooting at the nape of the neck should be abandoned.
D000003:Abattoirs; D000818:Animals; D002417:Cattle / Q000502:physiology*; D003243:Consciousness / Q000502:physiology; D003315:Cornea / Q000502:physiology; D004567:Electrodes, Implanted / Q000662:veterinary; D004569:Electroencephalography; D007103:Immobilization; D008297:Male; D008722:Methods; D012018:Reflex / Q000502:physiology