This case describes the clinical and radiographic appearance, medical treatment and long-term followupof a 6-year-old French trotter stallion that was referred with an acute onset of pain and swelling at thetail-head without a history of traumatic insult. Radiographic examination revealed multiple semicircular andmillet-sized radiolucencies at the endplates of several adjacent caudal vertebrae, indicative of infective discospondylitis.The horse made a full clinical recovery after 7 weeks of antibiotic treatment with oral trimethoprim-sulfonamides and successfully resumed its athletic activities. Follow-up radiography after one yearshowed only slight residual irregularity at the epiphyses, without exuberant new bone formation or persis tingradiolucencies.