Head-to-Back Stun-Kill

Head-to-back stun-killing is carried out by passing a current simultaneously through the brain and through the heart of the animal. In order to achieve this, head-to-back systems have the electrodes fixed in a handpiece (Figure 12), which is applied and operated manually by the slaughterman. To ensure correct positioning of the electrodes and to maintain contact, it must only be carried out on animals held in a restrainer.

The correct positioning of both electrodes is very important in order to ensure that the current flows through both the brain and the heart (Figure 13). With the animal restrained, the rear electrode should be placed firmly in the middle of the back above the heart (Figure 14). The front electrode should then be placed on the head, level with, or forward of the eyes (Figure 15). If a switch is fitted to the handset it should only be pressed once the electrodes are in position. The rear electrode should not be placed too far back, as the front electrode will also be in the wrong place and the animal will not be properly stunned. Electrode handsets that combine a water spray will help to reduce contact resistance and will, therefore, improve current flow. Additionally, they will decrease the likelihood of pelt damage of sheep by reducing the heating effect of the current at the site of the rear electrode.

Figure 12 Head-to-back stunner		Figure 13 Correct head-to-back electrode position
Figure 14 Correct back electrode positioning		Figure 15 Correct front electrode positioning

Next: Head-to-Body Stun-Kill