Recognizing pain in pigs is essential for welfare-appropriate treatment and management. This guide covers the science of porcine pain indicators and practical application on farm.
Pigs are prey species that mask pain and illness effectively — individuals showing obvious weakness or pain are vulnerable to attack from penmates. This evolutionary adaptation means that stockpeople must recognize subtle, early signs of pain to identify and treat affected animals appropriately. The default assumption that pigs showing no dramatic signs are pain-free is incorrect and leads to undertreatment of genuine welfare problems.
The Pig Grimace Scale provides a validated, objective tool for pain assessment. Facial action units — ear position (flattened and forward), orbital tightening, cheek tension, and nose bulging — change measurably in pigs experiencing acute pain. Training stockpeople to use grimace-based assessment at routine handling and health checks improves pain recognition and treatment timeliness.
NSAIDs are effective, safe, and welfare-essential for pain management in pigs. Meloxicam is the most commonly used and has evidence supporting its efficacy for post-castration pain, tail biting injuries, and lameness. Withdrawal periods must be observed in pigs destined for slaughter. Long-acting formulations improve compliance and maintain analgesic coverage during the post-procedural recovery period.