Mammary disorders in mares are rare and usually only one animal per paddock is affected. In this report, two mares with 7 and 9 years old, were concomitantly diagnosis of chronic pyogranulomatous mastitis, associated with the Splendore-Hoeppli reaction, indicative of botryomycosis a rare, chronic suppurative disease with microabscess formation, characterized by in vivo formation of eosinophilic materials around microorganisms or biologically inert material. Various bacteria can cause botryomycosis in horses, and the most frequently isolated one is Staphylococcus sp., particularly S. aureus. This report confirms the role of Staphylococcus sp.; however, specifically S. hyicus and S. cohnii that prior to the current report, had not been associated with cases of botryomycosis.
equine; mastitis; mammary gland; botryomycosis