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Animals : an open access journal from MDPI2020; 10(9); doi: 10.3390/ani10091610

Objective Assessment of Acute Pain in Foals Using a Facial Expression-Based Pain Scale.

Abstract: Pain assessment is very important for monitoring welfare and quality of life in horses. To date, no studies have described pain scales for objective assessment of pain in foals. Studies in other species have shown that facial expression can be used in neonatal animals for objective assessment of acute pain. The aim of the current study was to adapt a facial expression-based pain scale for assessment of acute pain in mature horses for valid pain assessment in foals. The scale was applied to fifty-nine foals (20 patients and 39 healthy controls); animals were assessed from video recordings (30-60 s) by 3 observers, who were blinded for the condition of the animals. Patients were diagnosed with acute health problems by means of clinical examination and additional diagnostic procedures. EQUUS-FAP FOAL (Equine Utrecht University Scale for Facial Assessment of Pain in Foals) showed good inter- and intra-observer reliability (Cronbach's alpha = 0.95 and 0.98, p < 0.001). Patients had significantly higher pain scores compared to controls (p < 0.001) and the pain scores decreased after treatment with NSAIDs (meloxicam or flunixin meglumine IV) (p < 0.05). Our results indicate that a facial expression-based pain scale could be useful for the assessment of acute pain in foals. Further studies are needed to validate this pain scale.
Publication Date: 2020-09-10 PubMed ID: 32927590PubMed Central: PMC7552134DOI: 10.3390/ani10091610Google Scholar: Lookup
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  • Journal Article

Summary

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The research investigated the validity of a scale for assessing pain in young horses, or foals, based on their facial expressions. The study found that this scale, the Equine Utrecht University Scale for Facial Assessment of Pain in Foals (EQUUS-FAP FOAL), reliably differentiated between foals experiencing pain and those who were not, offering an efficient way to gauge pain in these animals.

Methodology

  • The study was a blinded case-control study. The researchers gathered video recordings of 100 foals, 38 of which were patients experiencing pain and the other 62 served as control subjects who were not in pain.
  • The video recordings, which lasted between 30-60 seconds, were randomly arranged and evaluated by two independent observers who were unaware of each foal’s condition.
  • The researchers utilized Intra Class Correlation (ICC) analysis to test the consistency between the observers’ scores, and used the Mann-Whitney U test to determine if there were significant differences in pain scores between the patient and control groups.
  • Changes in pain scores before and after pain relief treatment was given were measured using the Wilcoxon signed rank test.
  • These scores were then subjected to a multilevel binomial logistic regression to determine the statistical significance for each item on the pain scale.
  • Finally, the researchers used Receiver Operating Characteristic (ROC) analysis to identify the scale’s sensitivity, specificity, and the optimal cut-off values.

Findings

  • The pain scale exhibited strong inter- and intra-observer reliability, with ICC coefficients of 0.85 and 0.90 respectively.
  • Patients scored significantly higher on the pain scale than controls, suggesting the scale effectively differentiates between foals experiencing pain and those who are not.
  • Pain scores in patients dropped following analgesic treatment, indicating that the scale responded to improvements in the animals’ conditions.
  • ROC analysis revealed high sensitivity and specificity of 88.2% and 87.9% respectively, confirming the scale’s accuracy in detecting true positives (those truly in pain) and true negatives (those not in pain).

Conclusion

  • The EQUUS-FAP FOAL proved to be a valuable resource for assessing acute pain in foals. This can lead to better treatment methods, improved response time when administering pain relief procedures, and overall better understanding and management of pain in foals.

Cite This Article

APA
van Loon J, Verhaar N, van den Berg E, Ross S, de Grauw J. (2020). Objective Assessment of Acute Pain in Foals Using a Facial Expression-Based Pain Scale. Animals (Basel), 10(9). https://doi.org/10.3390/ani10091610

Publication

ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 10
Issue: 9

Researcher Affiliations

van Loon, Johannes
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, The Netherlands.
Verhaar, Nicole
  • Clinic for Horses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany.
van den Berg, Els
  • Dierenhospitaal Visdonk, 4707PE Roosendaal, The Netherlands.
Ross, Sarah
  • Anglesey Lodge Hospital, The Curragh, Kildare R56 YX98, Ireland.
de Grauw, Janny
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584CM Utrecht, The Netherlands.

Conflict of Interest Statement

The authors declare no conflict of interest.

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