A novel method to measure the impact of sea transport motion on sheep welfare

Sheep are subjected to multiple stressors during commercial sea transport, including ship motion, ammonia, novel social dynamics and feed, high stocking density and multiple handling, all of which make it difficult to measure sheep responses to ship motion in isolation during a voyage. A practical method for measuring the impact of ship motions on the welfare of sheep on land was therefore developed, which exposed them to the three most important motions, roll (sideways), heave (vertical) and pitch (fore-aft). Roll and pitch motions were created using a programmable flight simulator platform, and heave motion was simulated elevating the entire apparatus with an electric forklift. Two main methods were developed to investigate the effect of these motions on sheep behaviour, physiology, balance, body posture, heart rate variability, rumination and feed intake. The first method evaluated each of the motions independently, replicating the frequency and magnitude of typical ship movements, taking into consideration the dimensions of a commercial vessel. The second method compared regular and irregular (random) movement sequences to investigate the importance of movement predictability on stress responses from sheep. The behaviour of sheep on the platform was similar to that which has been observed on ship. It is concluded that a detailed understanding of the responses of sheep to ship motion can be obtained by subjecting them to the different components of simulated transport using land-based equipment.