Effective management of pain is critical to the improvement of animal welfare. For this to
happen, pain must be recognised and assessed in a variety of contexts. Pain is a complex
phenomenon, making reliable, valid, and feasible measurement challenging. The use of
facial expressions as a technique to assess pain in non-verbal human patients has been
widely utilised for many years. More recently this technique has been developed for use in a
number of non-human species: rodents, rabbits, ferrets, cats, sheep, pigs and horses. Facial …