Serological and pathological investigation of brucellosis in dairy cows of Mymensingh district, Bangladesh

摘要

Brucellosis is a widespread and economically important infectious disease of animals and humans caused by the members of the genus Brucella. The disease is manifested by abortion, birth of unthrifty calves and retained placentae in female animals. The correct and prompt diagnosis is important for controlling and eradicating the disease from animals. This experiment was carried out in the Department of Pathology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh to detect Brucella antibody in dairy cows using Rose Bengal Plate Test (RBPT), indirect Enzyme Linked Immunosorbent Assay (i-ELISA) and histopathology. The study was carried out between the periods of January 2012 to September 2012. Placental tissue obtained from aborted cow and internal organs of aborted fetus were used in histopathological study. A total of 190 sera sample were collected with the history of reproductive disorders, like late abortion, retained placenta and anestrous from Veterinary Hospital, Bangladesh Agricultural University (BAU) and meat market Kewatkhali, Mymensingh. The seroprevalance of brucellosis using RBPT and iELISA were 2.63% and 1.05% respectively. Histopathological study revealed multifocal necrosis in hepatic parenchyma, depletion of lymphocytes in spleen and lymphnodes and distended trabeculi in spleen and lymphnodes in aborted calf, diffuse fibrosis around the placental epithelia and in placental tissues. Distinct histopathological lesions in the liver and spleen of Brucella suspected calf were not evident but the retained fetal membrane showed characteristics fibrosis and reactive cellular infiltration. It needs to adopt nucleic acid based technologies in order to confirm the species of Brucella involved and as well as to avoid cross reactivity of antibodies as seen in RBPT and iELISA.