Equine Welfare

Horse Poll Evil: Causes, Treatment and Welfare

Poll evil is a painful condition causing swelling and abscess formation at the top of the horse's head. Understanding causes and treatment prevents prolonged suffering.

Key Facts

Poll evil is an infection of the bursa at the poll, the highest point of the horse's head
Brucella abortus and Actinomyces species are common bacterial causes
Ill-fitting head collars and trauma are major predisposing factors
The condition progresses from swelling to abscess formation and draining tracts
Surgical debridement is often required in advanced cases
Welfare impact is significant due to pain when haltering or tying affected horses

Welfare Considerations

Poll evil causes chronic pain that interferes with basic management procedures. Horses with poll evil may resist haltering, become head-shy, or show behavioral changes reflecting discomfort. The location of the injury means that unavoidable daily handling becomes painful, creating a cycle of stress and distress. Prevention through proper equipment fitting is straightforward and cost-effective.

What You Can Do

Ensure all head collars and halters fit correctly — they should not press on the poll
Inspect the poll area regularly for swelling, heat, or sensitivity
Seek veterinary attention promptly for any swelling at the poll before abscessation occurs
Follow the full course of antibiotic treatment as prescribed
Review management practices to identify and eliminate trauma sources
Test mares in affected herds for brucellosis, which can cause poll evil