Epididymo-orchitis is one of the most important reproductive diseases in rams caused by various pathogens. The purpose of this study was to describe the clinical, ultrasonographic and histopathological characteristics of epididymo-orchitis caused by Brucella melitensis in rams. Nine rams with a large unilateral scrotal swelling were admitted to the surgery clinic. Full case history, thorough clinical examination, Rose Bengal test (RBT), Microagglutination test, ultrasonographic and histopathological examinations were carried out for all rams. The mean age of the diseased rams was 4±1.7 years. The diseased rams showed positive RBT (++) and the mean antibrucella titer was 1/140±7.8. For rams admitted between 1 to 2 months from the onset of clinical signs, the main ultrasonographic findings included thick hyperechoic scrotum, thick hyperechoic testicular tunics, anechoic fluid into vaginal cavity, enlarged testis, absence of testicular echogenic pattern, wide appearance of the mediastinum testis and multiple hypoechoic testicular and epididymal abscesses. For rams admitted between 2 to 3 months from the onset of clinical signs, hyperechoic multiple testicular abscesses, hyperechoic fibrous foci and thick hyperechoic epididymes were seen. The pathognomonic lesions were multiple focal testicular and epididymal abscesses, microgranulomas and microcalcification, necrosis of germinative epithelium, atrophy of seminiferous tubule with absence of spermatogenesis and interstitial edema associated with inflammatory cells infiltration. Scrotal lymph node showed focal caseous lymphadenitis with capsular edema. In conclusion, the ultrasonographic and histopathological findings of epididymo-orchitis caused by B. melitensis in rams are characteristics and vary depending on the chronological stage of the disease.

Key words: Brucella melitensis, Epididymo-orchitis, Microgranulomas, Rams, Scrotum