Basal cortisol concentrations related to maternal behavior during puppy development predict post-growth resilience in dogs.

A prolonged stress hyporesponsive period (SHRP) due to the mother's presence may delay the timing of glucocorticoid (GC) elevation in infants, thereby reducing the excessive stress response that would affect post-growth temperament. In dogs, the SHRP has been suggested to persist until postnatal week (PW) 4; therefore, PW 5, which SHRP may be prolonged by the mother dog, may be a critical point in the developmental stage of dogs to establish stress responsiveness. We conducted a long-term survey on the development of dogs to investigate i) whether the degree of the stress response at PW 5 is determined by maternal behavior and ii) whether it can predict post-growth stress responses and temperament in dogs.