Botryomycosis
Botryomycosis; also known as bacterial pseudomycosis is a rare chronic granulomatous bacterial infection that affects the skin, and sometimes the viscera.
Botryomycosis has been known to affect humans, horses, cattle, swine, dogs and cats. It can occur in recently castrated horses if proper hygiene isn't followed and the end of the spermatic chord becomes infected with S. aureus.