Farm Animals

Pig Welfare: Pain Assessment Using Grimace Scales

The Porcine Grimace Scale enables reliable, non-invasive pain assessment in pigs, transforming clinical practice and welfare research.

Key Facts

The Porcine Grimace Scale assesses orbital tightening, nose wrinkling, and ear position to score pain
The scale has been validated against known painful conditions including castration and tail docking
Training farm workers to use the grimace scale improves recognition and treatment of pain
Automated grimace scale scoring using computer vision is under commercial development

Welfare Considerations

Pain assessment tools like the Porcine Grimace Scale are transforming welfare science and clinical practice by making pain visible. Pigs that previously suffered undetected can now be identified and treated promptly. Widespread adoption of pain assessment training is a priority for welfare improvement.

What You Can Do

Advocate for pain assessment training using validated scales to be included in stockperson certification
Support research on automated grimace scale scoring for commercial pig operations
Engage with veterinary organisations developing pain assessment guidelines for pig practice