Social factors influencing cortisol modulation in dogs during a strange situation procedure

In human-dog relationships, positive interaction and social attention may mutually dampen stress responses. In humans, attachment representations and personality are linked to the modulation of individual stress reactions. We investigated the connections between dog attachment to the owner, owner attitudes and relationship toward the dog, and the personality of both on stress coping in dogs during the Ainsworth Strange Situation Procedure for dogs. For the first time, dog attachment patterns were assessed via the original Ainsworth attachment classification system. In addition, cortisol was measured from saliva in the context of play with the owner and 2 threat situations, once with and once without the owner present. We found that dogs classified as “securely attached” secreted less cortisol during the attachment (P = 0.008) and play situations (P = 0.031) and showed by trend a stronger cortisol reactivity during the threat situation when the owner was absent (P = 0.086) than dogs which were classified as “insecure.” The higher the owner's self-reported insecure-ambivalent attachment toward the dog and perception of the dog as a social support, the higher was the dog's cortisol reactivity during the Ainsworth Strange Situation Procedure (P = 0.004 and P = 0.018). Furthermore, it was found that owners high in neuroticism and agreeableness had dogs with low cortisol reactivity (P = 0.003 and P = 0.001). Older dogs showed less cortisol reactivity than younger ones (P = 0.023). Male dogs of male owners tended to show the lowest cortisol reactivity compared to all other human gender-dog sex combinations (P = 0.008). In conclusion, results show that secure dog attachment to the owner, owner-dog relationship, and personality of both influence the dog's stress coping.