Electrical stunning of sheep

In seventy Texel breed sheep with a live weight of about 43 kg electrocorticogram (ECoG) electrodes were implanted in the dura mater. The day after the operation the sheep were electrically stunned with scissor model tongs on the head. Various currents and voltages were used. A current strength of 0·33 A was statistically estimated to stun 90% of the sheep effectively, which means an immediate induction of a general epileptiform insult. The duration of an insult, using 600 V, is significantly longer than using 300 V, although the shortest duration was 23 s and 22 s, respectively. In all instances a paroxysmal ventricular tachycardia was observed after stunning. In the interests of animal welfare, electrical stunning of sheep should be performed with an amperage of at least 0·5 A (160 V) and throat cutting should take place within 16 s.