Pathomicrobial and Molecular Investigations of Respiratory System Diseases Affecting Buffaloes

Background: Pathomicrobial and molecular investigations of respiratory system diseases was undertaken on twelve adult buffalo carcasses received for necropsy examination at post mortem facility of Department of Veterinary Pathology, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana during the period from August, 2018 to February, 2019. Methods: After collection of the samples, laboratory work was undertaken in the laboratories of Department of Veterinary Pathology, Department of Animal Biotechnology and Central Laboratory of the College, LUVAS, Hisar, Haryana (India) in the year 2018-2019 regarding the examination of the clinical history, pathological, microbiological and molecular investigations. Result: The gross pathological changes observed in lungs were variable degree of vascular changes, mild to severe consolidation, fibrin deposition along with adhesions to the thoracic wall. Histopathological findings revealed abnormalities of inflation such as pulmonary emphysema, atelectasis, pulmonary congestion and haemorrhages which was associated with different types of pneumonia viz. fibrinous bronchopneumonia, suppurative giant cell pneumonia, interstitial pneumonia and serous pneumonia. Lung, heart blood and tracheal swab samples collected from the buffalo carcasses revealed eighteen bacterial isolates which were identified by Vitek 2 system. These include E. coli (11 isolates), Salmonella enteric enterica (2 isolates), Acinetobacter ursingii (1 isolate), Staphylococcus haemolyticus (1 isolate), Staphylococcus sciuri (1 isolate), Staphylococcus warneri (1 isolate) and Staphylococcus hominis (1 isolate) mostly belonging to opportunistic pathogen category. E. coli serotypes confirmed from these cases were O83, O149 and O8. The results of in vitro drug sensitivity testing revealed that most of bacterial strains were found sensitive to cefoperazone/sulbactum and co-trimoxazole. Molecular studies confirmed Bovine Herpes Virus-1 (BHV-1) infection in one case with Fibrinous bronchopneumonia through real-time quantitative PCR indicating the prevalence of the infection in the state.