Impact of Auditory and Olfactory Enhancement on Heart Rate Variability in Shelter Dogs

Mike Helshen^*
*Correspondence: Mike Helshen, Department of Veterinary Clinical Science, University of Hokkaido, Hokkaido 060-0808, Japan, Email:

Keywords

Heart rate variability • Shelter dogs • Auditory enhancement • Olfactory enhancement

Introduction

Shelter environments, despite their best intentions, often pose significant stressors to resident dogs. Confinement, high noise levels, unfamiliar surroundings, and frequent human and animal interactions can lead to chronic stress, manifesting in behavioral and physiological disturbances. One of the measurable physiological responses to stress is Heart Rate Variability (HRV), which reflects the balance between sympathetic and parasympathetic nervous system activities. High HRV is generally associated with good health and resilience to stress, whereas low HRV indicates chronic stress and poor health outcomes. Therefore, interventions that can improve HRV in shelter dogs are of great interest to researchers and animal welfare advocates [1].

Among the various enrichment strategies, sensory enrichment through auditory and olfactory stimuli has gained attention for its potential to reduce stress and improve the welfare of shelter dogs. Auditory enrichment involves the use of specific sounds or music, while olfactory enrichment employs scents that can have calming effects. This article aims to explore the impact of these sensory enhancements on HRV in shelter dogs, providing insights into their effectiveness and potential implementation in shelter settings [2].

Literature Review

The stress experienced by shelter dogs has been extensively documented in the literature. Studies have shown that prolonged exposure to stressful environments can lead to behavioral problems, such as increased aggression, anxiety, and stereotypic behaviors. Physiologically, stress can suppress immune function, disrupt normal metabolic processes, and negatively affect cardiovascular health. HRV is a reliable measure of these physiological changes, offering a non-invasive way to assess stress levels and autonomic nervous system activity in dogs. Auditory enrichment has been studied as a method to reduce stress in various animal species, including dogs. Classical music, for instance, has been shown to reduce barking and increase resting behavior in shelter dogs. Similarly, other forms of music, such as reggae and soft rock, have been found to lower heart rates and promote relaxation. The mechanisms behind these effects are believed to involve the modulation of the autonomic nervous system, leading to increased parasympathetic activity and reduced sympathetic arousal [3].

Olfactory enrichment, though less commonly studied than auditory enrichment, also holds promise for stress reduction in shelter dogs. Essential oils, such as lavender and chamomile, have been shown to have calming effects on dogs. These scents are thought to interact with the olfactory system, influencing brain regions involved in emotion and stress regulation. Studies have reported decreased barking and increased resting behaviors in dogs exposed to calming scents, suggesting a potential for olfactory enrichment to enhance welfare. Despite these promising findings, the impact of combined auditory and olfactory enrichment on HRV in shelter dogs has not been extensively explored. Given that HRV is a sensitive indicator of stress and overall well-being, understanding how these sensory enhancements influence HRV can provide valuable insights into their effectiveness as stress-reduction strategies [4].

Discussion

The potential benefits of auditory and olfactory enrichment for shelter dogs are supported by a growing body of research. Auditory enrichment, through the use of music and specific sounds, has been consistently shown to promote relaxation and reduce stress-related behaviors in dogs. Music therapy, for instance, has been effective in lowering heart rates and increasing HRV, indicating a shift towards parasympathetic dominance and reduced stress. The selection of appropriate music or sounds is crucial, as different auditory stimuli can have varying effects on dogs. Classical music, with its slow tempo and harmonious structure, appears to be particularly effective in promoting relaxation. Olfactory enrichment, though less studied, also shows promise in enhancing the welfare of shelter dogs. The use of calming scents, such as lavender and chamomile, can influence the olfactory system and subsequently affect brain regions involved in stress and emotion regulation [5].

The integration of auditory and olfactory enrichment presents a novel approach to enhancing the welfare of shelter dogs. By combining these sensory stimuli, it is possible to create a multi-sensory environment that more effectively addresses the diverse stressors experienced by shelter dogs. For instance, auditory enrichment can mask unpleasant sounds commonly found in shelter environments, while olfactory enrichment can provide a calming background scent. Together, these stimuli can create a more soothing and less stressful environment, promoting higher HRV and better overall health. Implementing these sensory enhancements in shelter settings requires careful consideration of several factors. The choice of auditory and olfactory stimuli should be based on evidence from existing research, ensuring that the selected stimuli are effective in promoting relaxation and reducing stress [6].

Conclusion

The use of auditory and olfactory enhancement offers a promising approach to improving the welfare of shelter dogs. By positively influencing HRV, these sensory enrichments can reduce stress levels and promote better overall health. The evidence suggests that classical music, specific sounds, and calming scents such as lavender and chamomile can effectively enhance HRV and reduce stress-related behaviors in shelter dogs. However, further research is needed to explore the combined effects of auditory and olfactory enrichment and to optimize their implementation in shelter settings.

In conclusion, sensory enrichment through auditory and olfactory stimuli represents a valuable tool for enhancing the well-being of shelter dogs. By creating a more soothing and less stressful environment, these interventions can improve HRV and promote better health outcomes. As our understanding of these sensory enhancements grows, it is crucial to continue exploring their potential and refining their application to ensure the best possible outcomes for shelter dogs.

Acknowledgement

None.

Conflict of Interest

None.

References

1. Behar, Joachim A., Aviv A. Rosenberg, Ori Shemla and Kevin R. Murphy, et al. "A universal scaling relation for defining power spectral bands in mammalian heart rate variability analysis." Front Physiol 9 (2018): 1001.

Google Scholar, Crossref, Indexed at

2. Blake, R. R., D. J. Shaw, G. J. Culshaw and Yolanda Martinez-Pereira. "Poincaré plots as a measure of heart rate variability in healthy dogs." J Vet Cardiol 20 (2018): 20-32.

Google Scholar, Crossref, Indexed at

3. Koelsch, Stefan and Lutz Jäncke. "Music and the heart." Euro Heart J 36 (2015): 3043-3049.

Google Scholar, Crossref, Indexed at

4. Buchbauer, Gerhard, Leopold Jirovetz and Walter Jäger. "Aromatherapy: Evidence for sedative effects of the essential oil of lavender after inhalation." Zeitschrift für Naturforschung C 46 (1991): 1067-1072.

Google Scholar, Crossref, Indexed at

5. Randall, David C., David R. Brown, Rebekah M. Raisch and Jeffrey D. Yingling, et al. "SA nodal parasympathectomy delineates autonomic control of heart rate power spectrum." Am J Physiol-Heart Circulatory Physiol 260 (1991): H985-H988.

Google Scholar, Crossref, Indexed at

6. De Vito, Giuseppe, S. D. R. Galloway, Myra A. Nimmo and Peter Maas, et al. "Effects of central sympathetic inhibition on heart rate variability during steady‐state exercise in healthy humans." Clin Physiol Function Imag 22 (2002): 32-38.

Google Scholar, Crossref, Indexed at