The effect of auditory stimulation on pet dogs' reactions to owner separation

The domestic dog has attracted notable attention in relation to the welfare benefits of auditory stimulation. Studies carried out in rescue kennels, an environment in which dogs are prone to chronic stress, have pointed to a calming influence of both classical music and audiobooks. The benefits of auditory stimulation for dogs experiencing more immediate types of stress, however, are still unknown. This investigation thus examined the effect of classical music and the spoken voice in the form of an audiobook on the behaviour of pet dogs in response to separation from their owners, a known short-term stressor. Three conditions of auditory stimulation were employed: (1) a control (the normal environment of the university research room), (2) classical music (Mozart’s Sonata K.448) and (3) an audiobook (Harry Potter and the Philosopher’s Stone). The effect of these conditions was explored using two approaches. Study 1 explored the effects of auditory stimulation using a between-subjects design. Sixty dogs were assigned to one of the 3 conditions and exposed to the relevant auditory stimulus for 1-hour. Each dog’s behaviour was recorded every 10 s using a purpose-designed ethogram. Latency data were recorded by video. Results revealed a significant effect of auditory condition on latency to lie down, latency to settle (i.e., lie down for >30 s) and speaker-directed gaze. Dogs exposed to classical music were significantly faster to lie down than animals in the audiobook condition and quicker to settle than animals in the audiobook and control conditions. Subjects in the audiobook condition spent significantly more time gazing at the speaker than animals in the classical music and control conditions. Dogs in the classical music condition also spent significantly more time looking towards the speaker than control animals. Study 2 examined the effects of auditory stimulation using a repeated measures design. Twenty-two dogs were exposed to each condition of auditory stimulation for 30 min, with a period of 10 min between conditions. Each animal’s behaviour was recorded as per Study 1. Only speaker-directed gaze differed significantly between conditions, with animals spending more time looking at the speaker in the audiobook and classical music conditions than the control. Overall, findings point to only a moderately calming effect of classical music, and no apparent welfare benefits of an audiobook, on dogs separated from their owners. The research points to auditory stimulation having little value to dogs in situations of short-term acute stress. Further research is recommended in this field, ideally in a wider variety of contexts than studied thus far.