Zylkéne to Load? The effects of alpha-casozepine on compliance and coping in horses during loading.

Horses are routinely travelled for access to safe off-road riding, veterinary care, breeding, sale or moving to a new home environment. However, transport is a known stressor in horses. For this reason, problem behaviour when loading is a common anecdotally reported issue which presents risks to handlers and horse welfare. Existing literature and manufacturers recommendations suggests that alpha-casozepine may be effective in improving the behaviour and welfare of horses during loading onto a vehicle for transport. The current paper aims to assess the behavioural and physiological effects of a commercially available alpha-casozepine feed supplement (Zylkéne Equine) in horses during loading and confinement on a transport lorry. Subjects (n = 10) were loaded once with the supplement and once without, in balanced random order. The handler was blind to treatment. Time to load onto the lorry, and movement of feet, licking and chewing, and vocalising within the lorry, were recorded as behavioural indicators of improved compliance and coping. Heart rate, heart rate variability, changes in salivary cortisol, and infrared thermography of both core temperature and the discrepancy between eyes, were measured as indicators of arousal. There were no significant differences in physiology between Treatment and Control (P > 0.05). There was a significant difference in Loading Time (P = 0.04), but no other behavioural indicator differed between Treatment and Control (P > 0.05). This indicates that alpha-casozepine does not affect a horse’s ability to cope with loading and confinement in a horse lorry, though it may improve loading times. Further work is required to ascertain whether the maximum dosage – twice that used here – might affect coping and behaviour in horses.