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Scientific reports2018; 8(1); 17501; doi: 10.1038/s41598-018-35561-7

Physiological outcomes of calming behaviors support the resilience hypothesis in horses.

Abstract: To manage a stressful stimulus animals react both behaviorally and physiologically to restore the homeostasis. In stable horses, a stressful stimulus can be represented by social separation, riding discomfort or the presence of novel objects in their environment. Although Heart Rate Variability is a common indicator of stress levels in horses, the behavioral mechanisms concurrently occurring under stressful conditions are still unknown. The sudden inflation of a balloon was administered to 33 horses. Video-recording of self-directed behaviors (snore, vacuum chewing, snort, head/body shaking) and monitoring of heart activity (HR and SDRR) were conducted for five minutes before (Pre-test) and after the stimulus administration (Stress-test). During the Stress-test, only snore and vacuum chewing increased and a significant increase was also recorded in both HR and SDRR. Moreover, the snore variation between the two conditions showed a significant correlation with the variation of both HR and SDRR. With the snore acting as stress-releasing behavior to restore basal condition, the homeostasis recovered via the enactment of such behavior could be physiologically expressed by an increasing vagal activity. Hence, the capacity to maintain homeostasis (resilience) could correspond to a prevalence of parasympathetic control on heart activity, intervening when certain behaviors are performed.
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Publication Date: 2018-11-30 PubMed ID: 30504840PubMed Central: PMC6269543DOI: 10.1038/s41598-018-35561-7Google 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.

The research explores how horses respond to stress and identifies specific behaviors, like snoring and vacuum chewing, that may facilitate a horse’s ability to regain calmness and physiological balance after a stressful event.

Understanding the Research Topic

  • The main focus of this study is to investigate how horses physiologically react to stress, and how they regain balance, or homeostasis, afterwards. Homeostasis refers to a stable, balanced, or constant condition in the body, maintained by biological processes.
  • The researchers wanted to better understand the specific behaviors horses use to mitigate stress and restore homeostasis.
  • Common stressors for horses can include social separation, discomfort during riding, or exposure to unfamiliar objects. This study introduced a sudden stimulus – the inflation of a balloon – to induce stress.

Methodology

  • The researchers used 33 horses for the experiment. They monitored and recorded the horses’ self-directed behaviors and heart activity for five minutes before and after introducing the stressor. The behaviors observed included snoring, vacuum chewing, snorting, and shaking of the head or body.
  • Heart activity was measured using Heart Rate (HR) and Standard Deviation of RR intervals (SDRR), with the latter being a common indicator of stress levels in horses.

Findings

  • The study found that during the stress test, only snoring and vacuum chewing increased significantly. Additionally, there was a significant increase in both HR and SDRR, indicating elevated stress.
  • The increased frequency of snoring between the pre-test and stress-test was significantly correlated with the variation in HR and SDRR, suggesting that the snoring behavior might be a stress-releasing mechanism for the horses.

Significance of the Findings

  • The researchers suggest that the horse’s ability to stabilize its physiological state after a stressful event could be linked to an increase in parasympathetic control over heart activity. Parasympathetic control is part of the nervous system that generally serves to slow the heart rate and calm the body.
  • Therefore, understanding specific calming behaviors like snoring may provide insights into a horse’s resilience, or the ability to maintain homeostasis under stress.

In summary, this research provides valuable insights into how horses physiologically respond to and mitigate stress, which has implications for horse care and management practices.

Cite This Article

APA
Scopa C, Palagi E, Sighieri C, Baragli P. (2018). Physiological outcomes of calming behaviors support the resilience hypothesis in horses. Sci Rep, 8(1), 17501. https://doi.org/10.1038/s41598-018-35561-7

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 8
Issue: 1
Pages: 17501
PII: 17501

Researcher Affiliations

Scopa, Chiara
  • Italian National Reference Centre for Animal Assisted Interventions, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro (Padua), Italy.
Palagi, Elisabetta
  • Unit of Ethology, Department of Biology, University of Pisa, Pisa, Italy.
Sighieri, Claudio
  • Department of Veterinary Sciences, University of Pisa, Pisa, Italy.
Baragli, Paolo
  • Department of Veterinary Sciences, University of Pisa, Pisa, Italy. paolo.baragli@unipi.it.

MeSH Terms

  • Animals
  • Behavior, Animal / physiology
  • Homeostasis
  • Horses / physiology
  • Vital Signs

Conflict of Interest Statement

The authors declare no competing interests.

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