Antigenic distribution, pathological changes, antibody response and serological detection in non-pregnant goats following experimental infection by Brucella melitensis

This study describes the pathological changes, antibody response, isolation and distribution patterns following exposure of non-pregnant goats to live Brucella melitensis. Eighteen healthy adult female goats were divided into two equal groups. Group 1 was infected via conjunctival sac with 109  cfu/ml of B. melitensis, while Group 2 was similarly exposed to sterile PBS. Serum and swabs from the eyes and vagina were collected at 5-day intervals. On days 15, 30 and 75 post-infection, 3 goats from each group were killed before the conjunctiva, ovary, oviduct, uterine horn, uterine body and vagina, the submandibular, prescapular and supramammary lymph nodes, the mammary gland, liver, spleen, urinary bladder and synovial membranes were collected for bacterial isolation and pathological study. Exposure of non-pregnant goats to B. melitensis did not produce clinical signs and gross lesions but produced mild necrosis and inflammation in the lymph nodes, the organs of reproductive tract, the mammary gland and urinary bladder. In general, microscopic lesions were most severe in the D75 goats, followed by D30 and D15 goats. Brucella melitensis was most frequent and significantly (p