Investigating the relationship between heart rate changes and the human-animal bond: Insights from an external telemetry system

Abstract

Heart rate changes and respiratory activities are vital physiological phenomena that provide valuable insights into the physiological and psychological states of family dogs. The bond between humans and their pet dogs necessitates a deeper understanding of this relationship. Therefore, the objective of this study was to investigate the human-animal bond by examining heart rate (HR), heart rate variability (HRV), respiratory rate (breathe per minute, BPM), and tidal volume (TV) using an external telemetry system. A total of ten dogs were selected as participants, and their cardio-respiratory responses were evaluated in an unfamiliar environment. The baseline data for the study was established during the first stage of the Strange Situation Test (SST), known as "dog with owner." The analysis focused on changes in HR, HRV, BPM, and TV throughout the different stages of the SST. Interestingly, the results demonstrated that changes in HR did not consistently correspond to changes in HRV across all stages. During the initial encounter with the stranger (episode b, stranger entering), there were notable percentage changes in HR, HRV, and TV, despite an overall increase in BPM, although not significant. In the third stage (stranger alone with the dog), both HR and HRV parameters, as well as TV, displayed increased percentage changes, whereas BPM exhibited a decrease. Furthermore, when the dog interacted with the stranger for the second time (episode f), HR and BPM increased, while HRV and TV decreased. This pattern suggests a shift towards a more active and alert state in response to the renewed social interaction. In contrast, when the dog was left alone (episode e), HR and BPM decreased, while HRV and TV increased. Overall, these findings provide evidence that changes in heart rate and respiratory parameters reflect the emotional stress experienced by family dogs in various social contexts. Moreover, the utilization of the external telemetry system in this study offers a promising model for investigating the effects of pharmacological interventions, behavioral interventions, and animal-assisted therapy in animals. By gaining a deeper understanding of the human-animal bond, we can further enhance the well-being and quality of life for both dogs and their human companions.