Poll evil and fistulous withers are painful bursitis conditions in horses causing abscesses, fistulas, and welfare-significant infections. Aggressive early treatment prevents chronic disease.
Both poll evil and fistulous withers cause significant, persistent pain in affected horses. The anatomical location of these bursae — at the poll and withers respectively — means that the pain directly affects tacking up, riding, and basic handling. Horses with poll evil resist headcollar fitting and bridling; those with fistulous withers cannot tolerate saddle placement or girthing. This pain-driven reluctance to accept normal handling is frequently misinterpreted as behavioral problems rather than welfare-significant pain.
Chronic cases develop complex fistulating tracts that are extremely resistant to treatment. The discharge from fistulas is purulent and malodorous; the surrounding tissue becomes progressively scarred and inflamed. Quality of life in horses with longstanding chronic poll evil or fistulous withers is significantly compromised.
Aggressive early treatment is the welfare-optimal approach. This includes culture-directed systemic antibiotics, local irrigation, and often surgical debridement of infected bursal tissue. Brucella testing is essential and has zoonotic implications. Early-stage cases often resolve with medical management; chronic cases require surgical intervention under general anaesthesia with extensive postoperative management.