In an ideal world, horses would be more motivated to respond to the cues of their handlers in stressful situations than giving in to their inherent fear response.
In practice, many riders have found this is not always the case.
Elke Hartmann and her colleagues, writing in the journal Animals, note that horses are flight animals by nature and usually react with avoidance behaviour in fear-inducing situations.
“Therefore, reducing fearfulness so that the horse is responsive to human signalling is highly desirable in most training systems,” they said.
It also has relevance for welfare and safety, because most behavioural fear reactions increase the risk of injury for both the horse and rider.
The researchers in Sweden and Denmark have delved into the nature of the horse-human relationship in their just-published study.
“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.”
The researchers described their preliminary study involving 12 Standardbred horses. They designed an experiment to investigate whether the horses developed an attachment bond with their trainer after a short period of frequent interactions.
Their study also aimed to explore how the type of training method may affect the horse-human relationship and how this shows in terms of ease of handling in a novel environment.
The horses were subjected to a fear-inducing test (novel objects were presented to the horses while close to two humans) and a handling test (being led past novel objects) to study any attachment-related behaviours and ease of handling.
The tests were performed both before and after the horses had been trained by the same female handler, each receiving 10 sessions of 15 minutes.
The horses were assigned to three groups of four, each receiving different conditioning protocols – either negative reinforcement, or combined negative reinforcement with positive reinforcement using either food or wither scratching.
In the pre-training tests, the two people were unfamiliar to the horses. When repeated after training, one was the familiar trainer, the other unfamiliar.
The horses showed reduced reactions in both the fear test (encountering novel objects with the trainer and a stranger present while moving freely) and the handling test (encountering novel objects while being led by the trainer versus a stranger) after training compared to before training.
However, the researchers could not provide conclusive evidence that horse-human relationships established during training constituted an attachment.
“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.”
Discussing their findings, the authors said their results aligned with a recent study that reported attachment-related behaviours of horses towards both their owner and a stranger.
However, the current finding that a few horses had lower heart rates when investigating the object closest to their trainer raised the question of whether they regarded the trainer as more experienced or reliable than the stranger, based on familiarity and previous calm and competent handling, or whether other human attributes affected their responses.
Training, in the form of 10 repeated 15-minute sessions every other day with the same person, had no effect on the horses’ responses in the fear test following training.
“One of the main purposes of the training was to allow horses to form a relationship with the trainer and increase the chances of an attachment bond developing.
“Consistent and appropriate interactions aligned with learning theory may have created positive affect, thereby encouraging approach behaviour of horses to the trainer but also to strangers.”
The lower heart rates for horses in the post-training test may indicate that the mere presence of a familiar person had a calming effect on the horses, but this did not manifest in an increased investigation of the objects nor more proximity-seeking.
The results could not demonstrate that horses develop an attachment bond after repeated interactions with their trainer, at least within the total duration of training in the current study, they said.
The researchers noted that there were large individual variations among the horses’ responses.
Further studies are needed to increase our understanding of horse-human relationships, they said.
Hartmann, E.; Rehn, T.; Christensen, J.W.; Nielsen, P.P.; McGreevy, P. From the Horse’s Perspective: Investigating Attachment Behaviour and the Effect of Training Method on Fear Reactions and Ease of Handling—A Pilot Study. Animals 2021, 11, 457. https://doi.org/10.3390/ani11020457