The overall aim with this thesis was to identify reliable ways to assess the emotional bond between dogs and humans and to investigate the effect of length of separation from the owner on dog behaviour upon reunion.
In Study I, an evaluation was made as to whether the Ainsworth’s Strange Situation Procedure (ASSP), developed in child psychology, can be reliably transferred to investigate attachment between dogs and humans. In a balanced cross-over design, 12 research dogs participated in the ASSP in two different treatments, where the target figure was either a familiar person or a stranger. Results showed that dogs clearly preferred to be in physical contact with the familiar person, indicating that the dogs discriminated between people according to their previous experience of the relationship. They also showed more intense greeting behaviour towards the familiar person. However, there was no evidence to support the earlier proposal that the emotional relationship with a familiar person is of the ‘secure base’ attachment type, since the results for this comparison were similar when the target figure in the ASSP was a stranger. In paper II, the behaviour and cardiac activity of privately owned dogs without separation anxiety was investigated when they were left alone at home for 0.5, 2 and 4h. Each period of separation was preceded and followed by a 10-min period during which the owner was present and could interact with the dog. It was found that dogs were inactive most of the time they were alone and that their behaviour did not change over time. However, the length of time left alone significantly influenced the dogs’ behaviour when the owner returned. After longer separation periods (2 and 4 h), dogs had a higher heart rate and expressed a higher frequency of behaviours previously suggested to indicate arousal (body shaking and lip licking) during reunion with the owner. Dogs also displayed more tail wagging and initiated more contact with their owners after longer times of separation, regardless of owner behaviour.
It was concluded that the ASSP is an inappropriate method to assess the emotional bond between dogs and humans due to inherent order effects in the procedure. Instead, dog behaviour upon reunion with their attachment figure is proposed as a better and more robust measure to assess the quality of the emotional bond
