Zenithson, Y. G., Pierce, B. J., Otto, C. M. et al. 2014. The effect of dog-human interaction on cortisol and behavior in registered animal-assisted activity dogs. Applied Animal Behaviour Science. 159, 69-81.

The effect of animal-assisted activities (AAA) on the animal participants has been minimally investigated, and the welfare of these animals has been questioned. To enhance our understanding of these animals’ welfare, we measured cortisol collected from serial saliva samples of 15 healthy adult dogs registered with an AAA organization. We collected saliva every 30 min before, during, and after a standardized 60-min session across three settings: an AAA session (activity) for college students in the communal area of a residence hall, a novel session located in a novel room without interaction with a stranger, and a home session inside each handler's own home. Each session was videotaped, and specific behaviors during 5-min petting interactions were coded. Salivary cortisol levels were significantly higher in the novel setting (0.397 μg/dL) compared to activity (0.257 μg/dL) and home (0.213 μg/dL) settings at time 30 min (P = 0.01 and P = 0.03, respectively). Dogs exhibited significantly more standing (59% vs 0%, P = 0.008) and ambulating (5.6% vs 0%, P = 0.001) behavior in the activity setting compared to the home at time 30 min, as well. Salivary cortisol level was negatively correlated with panting (P = 0.02) and standing (P = 0.02) at specific time points in the novel and activity settings, respectively. During the 60-min AAA session, salivary cortisol concentration and stress-associated behavior were not statistically different compared to when dogs spent the same amount of time in the home setting, suggesting that they were not distressed when participating in the AAA sessions. The predictability of the environment may be an important consideration when evaluating the effect of AAA on dogs.