Frontiers in veterinary science2019; 6; 162; doi: 10.3389/fvets.2019.00162

Elevated Sensitivity to Tactile Stimuli in Stereotypic Horses.

Abstract: Although stereotypic behaviors are a common problem in captive animals, why certain individuals are more prone to develop them remains elusive. In horses, individuals show considerable differences in how they perceive and react to external events, suggesting that this may partially account for the emergence of stereotypies in this species. In this study, we focused on crib-biting, the most common stereotypy displayed by horses. We compared how established crib-biters ("CB" = 19) and normal controls ("C" = 18) differed in response to a standard "personality" assessment test battery, i.e., reactivity to humans, tactile sensitivity, social reactivity, locomotor activity, and curiosity vs. fearfulness (both in novel and suddenness situations). Our analyses showed that crib-biters only differed from control horses in their tactile sensitivity, suggesting an elevated sensitivity to tactile stimuli. We suggest that this higher tactile sensitivity could be due to altered dopamine or endogenous opioid physiology, resulting from chronic stress exposition. We discuss these findings in relation to the hypothesis that there may be a genetic predisposition for stereotypic behavior in horses, and in relation to current animal husbandry and management practices.
Publication Date: 2019-05-31 PubMed ID: 31275947PubMed Central: PMC6593280DOI: 10.3389/fvets.2019.00162Google Scholar: Lookup
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  • Journal Article


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 focuses on crib-biting, a common stereotypy displayed by horses, investigating the potential causes, and identifying that crib-biters were shown to have an elevated tactile sensitivity, possibly due to chronic stress or genetic predisposition.


  • The researchers conducted a study by comparing how crib-biters and control horses without the stereotypy reacted differently to a standard personality assessment test battery.
  • The assessment included measuring the horses’ reactivity to humans, their tactile sensitivity, social reactivity, locomotor activity, and their balance of curiosity vs fearfulness in novel and suddenness situations.

Findings: Increased Tactile Sensitivity

  • The results of the study indicated that crib-biters differed from the control horses only in their tactile sensitivity.
  • Tactile sensitivity refers to the sensitivity of the horse’s sense of touch and the researchers identified an elevated level of this sensitivity in crib-biting horses.
  • This finding implies that an increased sensitivity to touch could be a characteristic of horses that exhibit the crib-biting stereotypy, suggesting this could be contributing to the development of the behavior.

Potential Causes & Implications

  • The study proposed that such heightened tactile sensitivity could result from altered dopamine or endogenous opioid physiology. This alteration may be caused due to chronic stress exposition that animals experience in their captive environments.
  • The researchers also suggested that the findings may support the hypothesis that there may be a genetic predisposition for stereotypic behavior in horses. This could mean some horses are inherently more likely to develop these behaviors than others.
  • The findings underpin the importance of considering the individual sensitivity differences and possible genetic predispositions in horses when developing animal husbandry and management practices, as these could potentially influence the development of stereotypic behaviors such as crib-biting.

Cite This Article

Briefer Freymond S, Bardou D, Beuret S, Bachmann I, Zuberbu00fchler K, Briefer EF. (2019). Elevated Sensitivity to Tactile Stimuli in Stereotypic Horses. Front Vet Sci, 6, 162.


ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 6
Pages: 162
PII: 162

Researcher Affiliations

Briefer Freymond, Sabrina
  • Agroscope, Swiss National Stud Farm, Avenches, Switzerland.
Bardou, Du00e9borah
  • Agroscope, Swiss National Stud Farm, Avenches, Switzerland.
Beuret, Sandrine
  • Faculty of Science, Institute of Biology, University of Neuchu00e2tel, Neuchu00e2tel, Switzerland.
Bachmann, Iris
  • Agroscope, Swiss National Stud Farm, Avenches, Switzerland.
Zuberbu00fchler, Klaus
  • Faculty of Science, Institute of Biology, University of Neuchu00e2tel, Neuchu00e2tel, Switzerland.
  • School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, Scotland.
Briefer, Elodie F
  • Institute of Agricultural Sciences, ETH Zu00fcrich, Zurich, Switzerland.


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