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Physiology & behavior2002; 76(2); 289-296; doi: 10.1016/s0031-9384(02)00698-4

Heart rate and heart rate variability during a novel object test and a handling test in young horses.

Abstract: Forty-one Dutch Warmblood immature horses were used in a study to quantify temperamental traits on the basis of heart rate (HR) and heart rate variability (HRV) measures. Half of the horses received additional training from the age of 5 months onwards; the other half did not. Horses were tested at 9, 10, 21 and 22 months of age in a novel object and a handling test. During the tests, mean HR and two heart variability indices, e.g. standard deviation of beat-to-beat intervals (SDRR) and root mean square of successive beat-to-beat differences (rMSSD), were calculated and expressed as response values to baseline measures. In both tests, horses showed at all ages a significant increase in mean HR and decrease in HRV measures, which suggests a marked shift of the balance of the autonomic nervous system towards a sympathetic dominance. In the novel object test, this shift was more pronounced in horses that had not been trained. Furthermore, statistical analysis showed that the increase in mean HR could not be entirely explained by the physical activity. The additional increase in HR, the nonmotor HR, was more pronounced in the untrained horses compared to the trained. Hence, it is suggested that this nonmotor HR might be due to the level of emotionality. HR variables showed consistency between years, as well as within the second year. These tests bring about a HR response in horses, part of which may indicate a higher level of emotionality; and horses show individual consistency of these HR variables over ages. Therefore, it is concluded that mean HR and HRV measures used with these tests quantify certain aspects of a horse's temperament.
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Publication Date: 2002-06-05 PubMed ID: 12044602DOI: 10.1016/s0031-9384(02)00698-4Google Scholar: Lookup
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  • Journal Article

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.

This research article studies the temperamental traits of young horses by using heart rate (HR) and heart rate variability (HRV) measures during novel object and handling tests. The results suggest that these measures might highlight differences in the temperament of horses that have received additional training compared to those that haven’t, and could indicate the level of emotionality in horses.

Study Design and Participants

  • The researchers used 41 young Dutch Warmblood horses in this study.
  • From the age of 5 months, half of these horses received additional training while the other half did not.
  • These horses were injected at 9, 10, 21, and 22 months of age with novel object and handling tests.
  • Herald rate (HR) and HRV measures were taken during these tests.

Test Method and Calculations

  • The mean heart rate and two heart variability indices—the standard deviation of beat-to-beat intervals (SDRR) and root mean square of successive beat-to-beat differences (rMSSD)—were calculated during the tests.
  • To determine the response to the tests, these measures were then compared to baseline measures.

Findings

  • The researchers observed a significant increase in mean HR and decrease in HRV measures in the horses during both tests at all ages.
  • This change suggests that the balance of the autonomic nervous system’s function shifted towards sympathetic dominance—associated with the body’s “fight or flight” response—during the tests.
  • This change in HR and HRV was more pronounced in horses that had not received additional training, particularly during the novel object test.
  • The increase in mean HR was found to be greater than could be explained by physical activity alone.
  • The increase in non-motor HR—which is the additional increase in HR beyond what’s expected for physical activity—was also more prominent in untrained horses. This suggests it may be related to the level of emotionality in the horses.
  • The HR variables remained consistent across different ages and within the second year of life, implying individual consistency in these HR measures.

Conclusions

  • The researchers concluded that mean HR and HRV measures can effectively quantify specific aspects of a horse’s temperament.
  • These HR measures could potentially be used as indicators of a horse’s emotional state or temperament during certain tests or situations.

Cite This Article

APA
Visser EK, van Reenen CG, van der Werf JT, Schilder MB, Knaap JH, Barneveld A, Blokhuis HJ. (2002). Heart rate and heart rate variability during a novel object test and a handling test in young horses. Physiol Behav, 76(2), 289-296. https://doi.org/10.1016/s0031-9384(02)00698-4

Publication

Physiology & behavior
ISSN: 0031-9384
NlmUniqueID: 0151504
Country: United States
Language: English
Volume: 76
Issue: 2
Pages: 289-296

Researcher Affiliations

Visser, E K
  • Division of Animal Sciences, Institute for Animal Science and Health, P.O. Box 65, NL-8200 AB, Lelystad, The Netherlands. e.k.visser@id.wag-ur.nl
van Reenen, C G
    van der Werf, J T N
      Schilder, M B H
        Knaap, J H
          Barneveld, A
            Blokhuis, H J

              MeSH Terms

              • Aging / psychology
              • Animals
              • Autonomic Nervous System / physiology
              • Data Interpretation, Statistical
              • Handling, Psychological
              • Heart Rate / physiology
              • Horses / physiology

              Citations

              This article has been cited 69 times.
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