Recognizing and treating pain in pigs improves welfare substantially, as this stoic species often masks pain in ways that lead to inadequate management in commercial settings.
Pig pain recognition is challenging because pigs as prey animals mask pain to avoid appearing vulnerable - a survival strategy that now results in suffering going unrecognized in farm settings. Pain monitoring in pigs requires knowledge of subtle behavioral indicators including altered posture, reduced activity, and changes in social interaction. The development of validated pig pain scales and facial action coding systems provides objective tools for training stockpersons to recognize pain with greater reliability. Routine painful procedures including tail docking and castration continue largely without pain relief in many production systems despite available, affordable analgesics. Improving stockperson training in pain recognition and implementing analgesic protocols for routine procedures would substantially reduce the burden of unrecognized and untreated pain across billions of pigs annually.