Development of a Donkey Grimace Scale to Recognize Pain in Donkeys (Equus asinus) Post Castration
Department of Animal Biology, University of California Davis, Davis, CA 95617, USA
Department of Genetics, Faculty of Veterinary Sciences, University of Córdoba, 14071 Córdoba, Spain
The Worldwide Donkey Breeds Project, University of Córdoba, 14071 Córdoba, Spain
San Francisco SPCA, Society for the Prevention of Cruelty to Animals, San Francisco, CA 94115, USA
Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California Davis, Davis, CA 95617, USA
International Animal Welfare Training Institute, School of Veterinary Medicine, University of California Davis, Davis, CA 95617, USA
Department of Animal Science, University of California Davis, Davis, CA 95617, USA
Authors to whom correspondence should be addressed.
Received: 11 July 2020 / Revised: 7 August 2020 / Accepted: 10 August 2020 / Published: 13 August 2020
Donkeys originally evolved as a desert animal, and unlike the horse (which flees or runs away from danger), the donkey fights to avert danger. Hence, donkeys are more stoic and tend to express fear, pain, and discomfort in more subtle ways than horses. For owners and practitioners, it can prove to be challenging to identify donkeys in a state of pain or discomfort until the animal has reached an advanced degree of disease, at which point veterinary intervention may be too late. This study aims to identify signs of pain from both facial and body parameters in donkeys undergoing a surgical procedure. Scores were based on noted signs of discomfort/pain from the observed body language of the face, such as the eyes, ears, nose, nostrils, and muzzle, along with their overall body appearance. The study demonstrated that developing a scoring system donkey grimace scale proved to be accurate in identifying discomfort related to pain. However, the accuracy of the scale can be influenced by the observers’ gender, level of donkey knowledge, and experience.