Strangles is a highly contagious respiratory infection of horses causing significant welfare harm through abscessation and complications, with biosecurity and vaccination preventing outbreaks.
Strangles causes significant suffering through large, painful abscesses that affect eating, drinking, and breathing. Horses with developing abscesses show high fever, nasal discharge, and obvious pain on palpation of the lymph nodes. Ruptured or lanced abscesses provide pain relief but require wound care. Complications including purpura hemorrhagica cause vasculitis with severe limb and muzzle swelling, and bastard strangles involves abscess formation at distant internal sites. The combination of acute pain, systemic illness, and potential serious complications makes strangles a significant welfare event. Prevention through vaccination and biosecurity, and rapid isolation of affected horses, limits both individual and population welfare harm.