War Exposure and Canine Cortisol Responses: Cross-Country Differences in Cortisol Profiles of Therapy Dogs

Dog assisted interventions (DAIs) are an established procedure to support military staff but their implementation during active warfare has not yet been systematically studied. Alongside, the welfare of therapy dogs participating in DAIs during war remains unexplored. Therapy dogs may develop clinically relevant emotional disorders, including trauma-related stress responses, analogous to human psychopathologies. The present study sought to monitor physiological arousal in therapy dogs performing DAI sessions with their handlers in two Ukrainian military hospitals (Vinnyzja and Kyiv). Thus, biomarkers of hypothalamic-pituitary-adrenal (HPA) axis activity including salivary, urinary and hair cortisol concentrations in Ukrainian (UA) therapy dogs were assessed to capture their acute and long-term stress responses. Moreover, cortisol levels from German (GE) therapy dogs, performing similar DAIs under peaceful conditions were gathered to compare cortisol levels between dogs. Results suggest that GE dogs exhibited significantly higher urinary and hair cortisol levels and significantly lower salivary cortisol concentrations, reflecting alterations in longer-term glucocorticoid secretion that is possibly caused by war-related stimulation in the UA cohort. In contrast, no significant differences in salivary cortisol emerged as a consequence of performing DAIs. The present findings suggest an environmental impact on therapy dogs’ cortisol secretion rather than involvement in DAIs.