Companion Animals

Strangles in Horses: Welfare and Outbreak Management

Welfare guide to equine strangles -- one of the most common and welfare-impacting horse infectious diseases.

Key Facts

Strangles is caused by Streptococcus equi and is the most commonly diagnosed infectious disease of horses globally
It causes severe swelling and abscessation of lymph nodes in the head and neck region
Affected horses develop high fever, nasal discharge, difficulty swallowing, and significant pain
Abscesses can rupture externally or internally -- internal rupture (guttural pouch empyema) causes serious complications
Bastard strangles occurs when the infection spreads to distant lymph nodes and organs -- often fatal
Recovery from natural infection confers long-lasting immunity in most horses
Vaccination is available but does not provide complete protection -- it reduces severity rather than preventing infection
Outbreak management requires strict isolation, biosecurity, and sometimes veterinary surgical drainage of abscesses

Welfare Significance

Strangles causes significant suffering -- the pain of enlarging abscesses, difficulty swallowing, and systemic fever make affected horses acutely unwell. Bastard strangles has a very poor prognosis and causes prolonged severe suffering. Early identification, isolation of affected and exposed horses, and appropriate veterinary management are essential welfare responses to any outbreak.

What You Can Do

Test horses for strangles carrier status (guttural pouch wash) before introducing them to new yards
Implement immediate strict isolation at the first suspicion of strangles
Provide appropriate pain relief and supportive care under veterinary guidance during active disease
Vaccinate against strangles to reduce severity in yards with endemic or recurrent disease