Published in Frontiers in Animal Science, the study led by Cornelia Sulonen and colleagues evaluated behavioral and physiological stress indicators in 20 shelter dogs, 30 rehomed dogs, and 33 control dogs raised from puppyhood in their original homes. Using a combination of behavioral tests, cortisol measurements, and owner questionnaires, the researchers examined how rehoming impacts dogs’ stress levels and their ability to bond with new caregivers.
Shelter dogs showed the shortest eye-contact duration in both the unsolvable problem task and dedicated eye-contact test, suggesting less confidence or comfort with humans in stressful or uncertain situations. However, no significant group differences emerged in short-term memory performance or overt stress-related behaviors.
Hair samples revealed that shelter dogs had elevated long-term cortisol levels compared to rehomed dogs, indicating higher chronic stress. Interestingly, the cortisol levels in rehomed dogs were not significantly different from those in control dogs, implying successful adaptation post-rehoming.
Behavioral synchronization—considered a sign of emotional closeness—was evident in both rehomed and control dog-owner dyads. Remarkably, owners of rehomed dogs reported a higher degree of emotional closeness than owners of control dogs, perhaps reflecting the deeper meaning placed on the relationship after a rehoming journey.
These findings challenge the assumption that rehomed dogs remain impaired by early experiences. Instead, they highlight the potential for recovery and resilient human-dog bonding, given supportive environments and committed new owners.
Source: Sulonen, C., Löf, J., Jensen, P., Lasses, K., Theodorsson, E., Quist, H., & Roth, L. S. V. (2024). Behavior, long-term stress and relationship to owner in relinquished dogs. Frontiers in Animal Science. https://doi.org/10.3389/fanim.2024.1362437
