Pain in horses is a crucial health and welfare issue that can lead to considerable suffering and distress. In horse veterinary care, the assessment and treatment of pain is still suboptimal because there is no ‘Gold Standard’ form of pain assessment and, similarly to other prey species, horses may suppress the exhibition of obvious signs of pain in the presence of potential predators (i.e. humans). The Horse Grimace Scale (HGS), a pain coding system based on six Facial Action Units (FAUs), was shown to be a valid and reliable indicator of postoperative pain in animals undergoing castration. The aims of this study were to refine statistical analysis of HGS data in order to: 1) investigate whether treatment, observer and horse itself affect the score of each FAU; 2) evaluate the overall relation between variables and 3) define a classifier able to estimate the pain condition of the horse. Forty-six horses were divided in the following treatment groups: undergoing surgical castration (pain group) or undergoing non-invasive indolent procedures under general anaesthesia (control group). Pictures of each horse face were captured before and 8 hours post-procedure (N=126) and then scored, using the HGS, by five trained observers blind to the experimental condition. Data were analysed with Analysis of Variance (ANOVA) with treatment as fixed effect and observer and horse itself as random effect. Multiple Correspondence Analysis (MCA) was used to evaluate relations between variables, Linear Discriminant Analysis (LDA) and Discriminant Correspondence Analysis (DCA) were used to find a classifier. Our results showed that treatment (pain VS control) significantly affected the scores of all the FAUs (P<0.001). Furthermore, the scores of stiffly backwards ears, orbital tightening, tension above the eye area, and prominent strained chewing muscles significantly contributed to the classification of the horses in the correct category (pain VS control) and to the definition of a classifier cut-off value. To date, the HGS has only been used as a research tool, our results suggest that it is possible to define a classifier and cut off values, thus advancing its applicability in horse veterinary care.

The Horse Grimace Scale: a useful tool in veterinary practice? / E. Dalla Costa, F. Dai, D. Stucke, D. Lebelt, R. Pascuzzo, S. Vantini, M. Leach, M. Minero - In: Recent advances in animal welfare science[s.l] : UFAW, 2016 Jun. - pp. 45-45 (( Intervento presentato al 5. convegno UFAW tenutosi a York nel 2016.

The Horse Grimace Scale: a useful tool in veterinary practice?

E. Dalla Costa
Primo
;
F. Dai
Secondo
;
M. Minero
Ultimo
2016

Abstract

Pain in horses is a crucial health and welfare issue that can lead to considerable suffering and distress. In horse veterinary care, the assessment and treatment of pain is still suboptimal because there is no ‘Gold Standard’ form of pain assessment and, similarly to other prey species, horses may suppress the exhibition of obvious signs of pain in the presence of potential predators (i.e. humans). The Horse Grimace Scale (HGS), a pain coding system based on six Facial Action Units (FAUs), was shown to be a valid and reliable indicator of postoperative pain in animals undergoing castration. The aims of this study were to refine statistical analysis of HGS data in order to: 1) investigate whether treatment, observer and horse itself affect the score of each FAU; 2) evaluate the overall relation between variables and 3) define a classifier able to estimate the pain condition of the horse. Forty-six horses were divided in the following treatment groups: undergoing surgical castration (pain group) or undergoing non-invasive indolent procedures under general anaesthesia (control group). Pictures of each horse face were captured before and 8 hours post-procedure (N=126) and then scored, using the HGS, by five trained observers blind to the experimental condition. Data were analysed with Analysis of Variance (ANOVA) with treatment as fixed effect and observer and horse itself as random effect. Multiple Correspondence Analysis (MCA) was used to evaluate relations between variables, Linear Discriminant Analysis (LDA) and Discriminant Correspondence Analysis (DCA) were used to find a classifier. Our results showed that treatment (pain VS control) significantly affected the scores of all the FAUs (P<0.001). Furthermore, the scores of stiffly backwards ears, orbital tightening, tension above the eye area, and prominent strained chewing muscles significantly contributed to the classification of the horses in the correct category (pain VS control) and to the definition of a classifier cut-off value. To date, the HGS has only been used as a research tool, our results suggest that it is possible to define a classifier and cut off values, thus advancing its applicability in horse veterinary care.
Settore AGR/19 - Zootecnica Speciale
giu-2016
Book Part (author)
File in questo prodotto:
File Dimensione Formato  
york-2016---programme-and-abstracts-23-june.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 1.48 MB
Formato Adobe PDF
1.48 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/446892
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact