Investigations on respiratory affections in adult cattle in Haryana

Pathobiological investigation of the respiratory affections of ten adult cattle received for necropsy examination (August, 2018 to February, 2019) at post mortem facility of Department of Veterinary Pathology, COVSc., Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar was undertaken. The pathological changes observed in adult cattle included abnormalities of inflation such as pulmonary emphysema; atelectasis; vascular disturbances such as pulmonary congestion and haemorrhage, associated with one or another type of pneumonia (granulomatous, sero-fibrinous and/or interstitial pneumonia). Microbiological isolations from lungs, heart blood and tracheal swab revealed nine (09) bacterial isolates belonging to E. coli (4 isolates), Staphylococcus lentus (1 isolate), Aerococcus viridans (2 isolates), Enterobacter cloacae dissolvens (1 isolate) and Klebsiella pneumonia ssp. pneumonia (1 isolate). E. coli isolates detected belonged to O83, O134 and O157serotypes. The results of in-vitro drug sensitivity revealed that most of bacterial strains were found sensitive to gentamicin, cefoperazone/sulbactum. Molecular studies using conventional PCR revealed the presence of both Mycobacterium bovis and Mycobacterium tuberculosis infection in three cases showing granulomatous pneumonia and bovine herpes virus-1 (BoHV-1) infection in one case with interstitial pnuemonia by real-time quantitative PCR. Immunohistochemical studies using Mycobacterium bovis antigen revealed the presence of Mycobacterium bovis bacterial antigen in lung tissues of all the three cases with granulomatous pneumonia and were found positively correlated with histopathology, acid fast staining and molecular methods for confirmatory diagnosis.