From the Horse’s Perspective: Investigating Attachment Behaviour and the Effect of Training Method on Fear Reactions and Ease of Handling—A Pilot Study

SIMPLE SUMMARY: Optimising horse–human relationships can promote positive experiences and advance the welfare and safety of both dyad members. Attachment and bonding are key components in such relationships, and horses are good candidate subjects for studying bonding processes due to their social nature, artificial selection for trainability and their dependence on human care in a domestic context. However, the factors that contribute to successful relationships remain unclear. This preliminary study on 12 horses investigated whether horses develop an attachment bond with their trainer after a short period of frequent interactions. The study also aimed to explore how the type of training method (negative reinforcement and two types of combined reinforcement) may affect the horse–human relationship and how this manifests as ease of handling in a novel environment. The horses showed reduced reactions in both the fear test (encountering novel objects with the trainer and a stranger present while moving freely) and handling test (encountering novel objects while being led by the trainer versus a stranger) after training compared to before training. However, we could not provide conclusive evidence that horse–human relationships established during training constitute an attachment. Suggestions for future studies are provided. ABSTRACT: The study investigated equine responses to novelty and handling, aiming to reveal whether horse–human relationships reflect criteria of an attachment bond. Twelve adult Standardbreds were subjected to a fear-eliciting test (novel objects presented close to two humans) and a handling test (being led passing novel objects) to study attachment-related behaviours and ease of handling. The tests were performed both before (pre-test) and after (post-test) horses had been trained by the same female handler (10 sessions of 15 min). Horses were assigned to three groups of four, each of which underwent different operant conditioning protocols: negative reinforcement (NR; pressure, release of lead, and whip tap signals) or combined NR with either positive reinforcement using food (PRf) or wither scratching (PRs). Results showed that neither familiarity of the person nor training method had a significant impact on the horses’ behavioural responses in the post-tests. However, horses showed decreased heart rates between pre- and post-tests, which may indicate habituation, an effect of training per se, or that the presence of the familiar trainer served to calm the horses during the challenging situations. There were large individual variations among the horses’ responses and further studies are needed to increase our understanding of horse–human relationships.