Research has repeatedly shown that children with autism benefit from equine-assisted interventions, but how do the horses feel about it?
Researchers in Italy noted the increasing attention being given to horse-related work with autistic children, as the activities have been shown to provide physical and psychological enrichment.
However, children with autism could show inappropriate behaviours, potentially affecting the welfare of the horses.
Laura Contalbrigo and her colleagues, in a multicentre study published in the journal Animals, set out to investigate behavioural and physiological indices of stress in horses involved in standardised sessions with children with autism compared to sessions involving typically developing children.
The research, which involved 19 horses of various breeds and 38 children aged 6 to 12, compared the behavioural and physiological responses of horses between sessions and among session phases.
Stress-related behaviours, heart rate, heart-rate variability, and eye temperature were recorded during the riding sessions. Blood samples were also collected from horses before and after each session to monitor changes in blood adrenocorticotropic hormone (ACTH), cortisol, and catecholamines, levels of which can indicate stress.
The results indicated a lower sympathetic tone in horses involved in sessions with children affected by autism. The researchers found a significantly smaller increase of adrenaline in sessions with autistic children compared to those with traditionally developing children.
“Adrenaline is responsible for the immediate response of the sympathetic branch of the autonomic nervous system to stressors; therefore, this result suggests diminished arousal of the horse in equine-assisted interventions with children with autism spectrum disorder.
“This lack of arousal may be related to stimulus-evoked expectations resulting from environmental information that the horse receives from the handler, the child, and the overall setting,” they said.
The horses used in the study are routinely employed in equine-assisted interventions, performing recurring tasks and activities, the authors noted. Therefore, the lack of activation of the sympathetic nervous system while working with children with autism may be due to a reduced expectation of novelty, or an implicit solicitation to restrain their activation by the handler, as they are dealing with a child that needs special attention and care.
In general, the results indicated that the stress responses in horses involved in equine-assisted interventions did not differ as a function of the horse being ridden by autistic children or traditionally developing children.
When considering only horse behaviours, no significant differences were found between the two groups. “However, an interesting result was found when analysing stress-related behaviours during the different phases of each session. In particular, a higher frequency of behaviours indicative of stress was found in the stationary phase, while resting phases, especially mounting and dismounting, appeared as the most challenging for the animal.
“It is possible to hypothesize that ill-fitted tack, type of handler restraint or children not very experienced with the horse may cause discomfort during mounting and dismounting,” the researchers said.
The signs of stress seen in the mounting and dismounting phases were independent of the children’s behaviour.
The authors suggested that commonly used behavioural requests in the different phases of the riding session should be managed with much more attention by the horse handler during sessions to avoid stressful situations for the animal. “We conclude that professionals working in equine-assisted interventions should increase their awareness of animal welfare and refine riding practices, taking into account the horse’s needs.
“Future large-scale studies need to be addressed to investigate positive emotion indicators in horses during equine-assisted intervention sessions and their reactions to human behaviours performed by different people.”
The study team comprised Laura Contalbrigo, Marta Borgi, Marta De Santis, Barbara Collacchi, Adele Tuozzi, Marica Toson, Veronica Redaelli, Rosangela Odore, Cristina Vercelli, Annalisa Stefani, Fabio Luzi, Emanuela Valle, and Francesca Cirulli, with a range of Italian institutions.
Contalbrigo, L.; Borgi, M.; De Santis, M.; Collacchi, B.; Tuozzi, A.; Toson, M.; Redaelli, V.; Odore, R.; Vercelli, C.; Stefani, A.; Luzi, F.; Valle, E.; Cirulli, F. Equine-Assisted Interventions (EAIs) for Children with Autism Spectrum Disorders (ASD): Behavioural and Physiological Indices of Stress in Domestic Horses (Equus caballus) during Riding Sessions. Animals 2021, 11, 1562. https://doi.org/10.3390/ani11061562