Acute changes in oxytocin predict behavioral responses to foundation training in horses

Ensuring horse welfare is a central aim in equestrian activities. Training an important context for welfare, as horses form long-lasting representations of people and actions at young age. However, only few studies have addressed horses’ emotional responses during early training with humans. In this study, we followed N = 19 horses, including naïve yearlings more experienced two- to three-year-olds, through five foundation sessions over nine months. Our goal was combine physiological behavioral measures assess training. Specifically, measured salivary oxytocin (sOXT) 100 samples cortisol (sCORT) 96 before after sessions. We also recoded Changes sOXT predicted individual variation responses: Horses who showed affiliative human-directed behaviors had increases sOXT, while indicators discomfort decreases sOXT. Salivary not related responses, but lower sCORT concentrations both training, all indicative fear or progressed. addition, increased longer sessions, consistent the established role responding physical stressors. conclude that positive negative corresponds acute changes suggesting may be useful non-invasive indicator horses.