Attachment style classification in the interspecific and intraspecific bond in dogs

There is scientific evidence that adult dogs establish attachment bonds towards their owners that share similar features with the child-mother bond. On the contrary, the nature of the bond between two adult dogs is still unclear. The aim of the study was to compare the interspecific and intraspecific attachment bond with a particular focus on the attachment style classification. The Ainsworth Strange Situation Test was used to analyse the behaviour of 14 dogs (8 females and 6 males) tested twice: once with the owner and once with a cohabitant dog, in a counterbalanced order. Frequency and duration of 22 behaviours were measured and compared using the Wilcoxon test (p<0.05). Dogs were also classified as either securely or insecurely attached. When tested with the conspecific, dogs spent more time in “vocalizations” (p=0.001) and “proximity to door” (p=0.001), while, on the contrary, they spent more time in “contact” (p=0.016) during the interspecific procedure, suggesting a higher level of stress for dogs tested without their owners. As for the attachment style towards the cohabitant dog, 57.1% of dogs were classified as securely and 42.8% as insecurely attached. No agreement was found in the classification of attachment style between the intraspecific and interspecific tests (Cohen’s kappa =-0.089). The results on attachment style classification suggests that, in dogs as in infant-caregiver dyads, the secure attachment is the most represented, both for the interspecific and intraspecific procedures, and that dogs can show different styles towards different individuals. Nevertheless, further research is needed, especially for the intraspecific procedure.