Accurate recognition of pain in farm animals is fundamental to welfare assurance. Understanding the behavioural and physiological indicators of pain across species enables better assessment and treatment decisions.
The development of validated pain assessment tools for farm animals represents a significant advance in applied animal welfare science. Grimace scales - standardised scoring of facial action units - allow repeatable, objective pain scoring that can be incorporated into routine clinical and welfare assessments. Their value lies in detecting pain that behavioural observation alone might miss: a sheep standing quietly may still show facial tension indicative of pain. In practice, effective pain recognition requires trained observers who know their species' normal behaviour well enough to detect deviations. Pain management in farm animals has been historically underused, partly due to regulatory restrictions on analgesic use (veterinary prescription required) and partly due to underestimation of pain prevalence. The growing body of pain assessment science is shifting this: welfare auditing increasingly incorporates pain indicators as mandatory outcome measures.