Recognising pain in animals requires validated assessment tools; advances in pain science have transformed veterinary practice and farm animal health monitoring.
Accurate pain assessment prevents both under-treatment (causing suffering) and over-treatment (causing drug toxicity). Grimace scales based on facial muscle activation have revolutionised pain assessment in laboratory rodents, horses, and rabbits. Validated composite scales for dogs and cats allow clinical scoring and treatment decisions. Farm animal pain recognition training for stockpeople significantly improves treatment rates and welfare outcomes. Pain that is not recognised cannot be treated.