Towards a Virtual Fencing System: Training Domestic Sheep Using Audio Stimuli

Simple Summary Virtual fencing is useful for restricting animal movement in a controlled environment with cost and maintenance benefits over physical fencing. Physical fencing is also rigid, which does not allow for flexible use of grazing resources by farmers. The proposed study describes the use of a welfare-friendly virtual fence system over a typically used electric shock fence as an additional stimulus to restrict animal access to designated areas. The virtual fence was operated by an acoustic device, carried on the individual sheep. Sounds in the range of 125 Hz to 17 kHz and white noise were used to discourage seven Hebridean ewes from approaching a restricted area and feeding at a feed bowl. Two trials, performed a year apart, revealed that sounds in the range 125 to 440 Hz; 10 to 17 KHz could prevent sheep from approaching a feeding station (success rate 90%). In 78.5% of the trials, the animal behavior was observed to be the undisturbed movement away from the feed bowl when the acoustic stimulus was employed. Fencing in livestock management is essential for location and movement control yet with conventional methods to require close labour supervision, leading to increased costs and reduced flexibility. Consequently, virtual fencing systems (VF) have recently gained noticeable attention as an effective method for the maintenance and control of restricted areas for animals. Existing systems to control animal movement use audio followed by controversial electric shocks which are prohibited in various countries. Accordingly, the present work has investigated the sole application of audio signals in training and managing animal behaviour. Audio cues in the range of 125-17 kHz were used to prohibit the entrance of seven Hebridean ewes from a restricted area with a feed bowl. Two trials were performed over the period of a year which were video recorded. Sound signals were activated when the animal approached a feed bowl and a restricted area with no feed bowl present. Results from both trials demonstrated that white noise and sounds in the frequency ranges of 125-440 Hz to 10-17 kHz successfully discouraged animals from entering a specific area with an overall success rate of 89.88% (white noise: 92.28%, 10-14 kHz: 89.13%, 15-17 kHz: 88.48%, 125-440 Hz: 88.44%). The study demonstrated that unaided audio stimuli were effective at managing virtual fencing for sheep.

Automated summary

Virtual fencing system using acoustic stimulation can effectively manage sheep behavior and restrict their access to designated areas. The study demonstrates that sound signals in specific frequency ranges can successfully discourage sheep from entering restricted areas.