Pain Assessment in Pigs: Tools and Clinical Application

Accurate pain assessment in pigs is fundamental to welfare management, yet validated tools for pig pain recognition have only recently been developed and adoption in practice remains limited.

Key Facts

The Pig Grimace Scale uses facial expression changes to assess acute pain in pigs
Validated pain indicators include orbital tightening, cheek flattening, and ear position changes
Behavioural indicators including posture, activity, and social interaction supplement facial assessment
Pain assessment is essential before and after routine procedures including castration and tail docking
Underrecognition of pain in pigs leads to inadequate analgesia and prolonged suffering

Welfare Considerations

Pain recognition in pigs has historically been poor due to the species tendency to mask pain signs as an anti-predator behaviour, combined with limited validated assessment tools. The development and validation of the Pig Grimace Scale represents a significant advance in welfare management, providing stockpersons with an objective tool to assess pain intensity and treatment response. Training farm staff in pain recognition using validated tools, combined with prescribing appropriate analgesics for painful procedures, represents the most practical welfare improvement available to the pig farming sector.

What You Can Do

Implement Pig Grimace Scale training for all stockpersons working with pigs
Establish analgesia protocols for all potentially painful procedures including castration, tail docking, and injury treatment
Monitor pain assessment tool use through farm health and welfare plans
Advocate for mandatory pain recognition training in pig stockperson qualification programmes
Support research into development and validation of improved pain assessment tools for pigs