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Home / Equine Research Bank / Horm Behav / Cortisol release and heart rate variability in horses during...
Hormones and behavior2009; 57(2); 209-215; doi: 10.1016/j.yhbeh.2009.11.003

Cortisol release and heart rate variability in horses during road transport.

Abstract: Based on plasma cortisol concentrations it is widely accepted that transport is stressful to horses. So far, cortisol release during transport has not been evaluated in depth by non-invasive techniques such as analysis of salivary cortisol and faecal cortisol metabolites. Transport also causes changes in heart rate and heart rate variability (HRV). In this study, salivary cortisol, faecal cortisol metabolites, heart rate and HRV in horses transported by road for short (one and 3.5 h) and medium duration (8 h) were determined. With the onset of transport, salivary cortisol increased immediately but highest concentrations were measured towards the end of transport (4.1+/-1.6, 4.5+/-2.6, 6.5+/-1.8 ng/ml in horses transported for one, 3.5 and 8 h, respectively). Faecal cortisol metabolite concentrations did not change during transport, but 1 day after transport for 3.5 and 8 h had increased significantly (p<0.01), reflecting intestinal passage time. Compared to salivary cortisol, changes in faecal cortisol metabolites were less pronounced. Heart rate increased and beat-to-beat (RR) interval decreased (p<0.05) with the onset of transport. Standard deviation of heart rate increased while root mean square of successive RR differences (RMSSD) decreased in horses transported for 3.5 (from 74+/-5 to 45+/-6 ms) and 8 h (from 89.7+/-7 to 59+/-7 ms), indicating a reduction in vagal tone. In conclusion, transport of horses over short and medium distances leads to increased cortisol release and changes in heart rate and HRV indicative of stress. The degree of these changes is related to the duration of transport. Salivary cortisol is a sensitive parameter to detect transient changes in cortisol release.
Copyright 2009 Elsevier Inc. All rights reserved.
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Publication Date: 2009-11-26 PubMed ID: 19944105DOI: 10.1016/j.yhbeh.2009.11.003Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article examined the stress levels in horses during road transport by looking at cortisol release and heart rate variability. The parameters being monitored included salivary cortisol, faecal cortisol metabolites, heart rate and heart rate variability (HRV) during short and medium duration transports.

Methodology

  • The scientists collected and analyzed data from horses transported by road for various durations: one, 3.5 hours, and eight hours.
  • They measured the horses’ salivary cortisol and faecal cortisol metabolites (both indicators of stress) along with their heart rates and heart rate variability (HRV).

Findings

  • Salivary cortisol levels increased immediately with the onset of transport but reached their highest concentrations towards the end of transport.
  • The concentration of faecal cortisol metabolites did not change during transport but it increased significantly a day after transport for 3.5 and 8 hours, which reflects the intestinal passage time.
  • Changes in faecal cortisol metabolites were less pronounced compared to the changes in salivary cortisol.
  • Heart rate increased and the interval between heartbeats (RR interval) decreased with the onset of transport.
  • The standard deviation of the heart rate increased while the root-mean-square of successive RR differences (RMSSD) decreased in horses transported for 3.5 and 8 hours, signaling a reduction in vagal tone (part of the brain that regulates heart rate).

Conclusion

  • The transport of horses over short and medium distances leads to increased cortisol release and changes in heart rate and HRV which are indicative of stress.
  • The degree of these changes is related to the duration of transport.
  • Salivary cortisol is a sensitive parameter to detect transient changes in cortisol release, making it a reliable method for monitoring stress in transported horses.

Cite This Article

APA
Schmidt A, Möstl E, Wehnert C, Aurich J, Müller J, Aurich C. (2009). Cortisol release and heart rate variability in horses during road transport. Horm Behav, 57(2), 209-215. https://doi.org/10.1016/j.yhbeh.2009.11.003

Publication

Hormones and behavior
ISSN: 1095-6867
NlmUniqueID: 0217764
Country: United States
Language: English
Volume: 57
Issue: 2
Pages: 209-215

Researcher Affiliations

Schmidt, Alice
  • Graf Lehndorff Institute for Equine Science, 16845 Neustadt (Dosse), Germany.
Möstl, Erich
    Wehnert, Christiane
      Aurich, Jörg
        Müller, Jürgen
          Aurich, Christine

            MeSH Terms

            • Animals
            • Automobiles
            • Feces / chemistry
            • Female
            • Heart Rate
            • Horses / physiology
            • Hydrocortisone / analysis
            • Hydrocortisone / metabolism
            • Male
            • Motion
            • Orchiectomy
            • Saliva / chemistry
            • Saliva / metabolism
            • Stress, Psychological / physiopathology
            • Time Factors

            Citations

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