Electric shock conditioning of sheep to avoid feed supplement troughs in field investigations of diet supplementation.

Abstract

We examined the possibility of conditioning grazing sheep not to eat freely available supplements. The technique used a standard electric fence energizer connected to a trough filled with molasses. A flock of 60 wethers and another flock of 120 ewe and wether hoggets were each divided into three treatment groups. All treatment groups were initially allowed access to the molasses trough with the energizer switched off. After two days, the control group was removed while the energizer was switched on for the other two groups; the voltage was measured at 6,500 volts. Sheep in one group were removed from the yard after one day's exposure while the other sheep were left with the energizer on for a further two days. One and four weeks later all sheep were exposed to the molasses trough without the energizer turned on. The wethers and hoggets were then placed in 120 and 250 ha paddocks. Numbers of sheep visiting the troughs were checked 6, 18, 22 and 26 weeks after introduction. Total success was achieved in creating avoiders and acceptors in their respective groups in the yard. None of the control group rejected supplements throughout the experiment in the paddocks. However, for the other wether groups between 70% and 73% respectively rejected the supplement. For the hogget groups the rejection rates were 74% and 70%. The behaviour and conditioning of the animals to avoid the troughs particularly stressful to the individual sheep. While the technique supplemented and non-supplemented sheep within one paddock.