108 Effects of equine assisted activities on stress-related behaviors exhibited by horses

Abstract

The various benefits of equine assisted activities (EAA) programs on humans have been studied and documented, whereas the effects of these programs on their equine counterparts have not been as thoroughly investigated. The objective of this study was to investigate the effects of EAA sessions with veterans with posttraumatic stress disorder (PTSD) on stress-related behaviors exhibited by horses. During the 8-week study, horses were assigned to 30-min horsemanship sessions with veterans with PTSD (EAA, n = 5) or a 30-min standing control with little to no human interaction in a small section of the same arena (CON, n = 5). Sessions occurred weekly, with EAA and CON horses participating regularly in similar work. EAA horses were videotaped from 3 different angles to capture the entirety of the arena used for the sessions, whereas CON horses were videotaped at one angle capturing the entirety of the stall they were enclosed in. Video was captured for the duration of the 30-min sessions. Video was then edited using Adobe Premiere Pro and the veterans’ faces redacted for privacy. Frequency and duration of stress-related behaviors was logged by trained observers using an ethogram in the BehavioralObservation Research Interactive Software (BORIS). Data were analyzed using a Poisson distribution repeated measures mixed model ANOVA with fixed effects of week and treatment and their interaction, and random effect of horse. Statistically different means were separated using Tukey's method. Significance was set at P ≤ 0.05. The total number of stress-related behaviors exhibited by horses was significantly different between EAA (19.8 ± 2.3 behaviors) and CON (35.3 ± 2.6 behaviors) (P = 0.0273). The number of unique stress-related behaviors exhibited by horses was also significantly different between EAA (5.9 ± 0.4 unique behaviors) and CON (7.7 ± 0.3 unique behaviors) (P = 0.0488). There was no difference between EAA and CON horses for the duration of stress-related behaviors. Horses appeared to exhibit more stress-related behaviors under isolation with little human interaction than when working with veterans with PTSD.