Occurrence and aetio-pathological study on interstitial pneumonia of sheep (Ovis aries)

Abstract

The present study was conducted to evaluate the interstitial pneumonia associated with the bacterial aetiology in sheep from Jaipur Division, Rajasthan. A total of 436 lungs were examined of which 102 lungs (23.40%) found with gross lesions were collected intact for the study. For bacteriological examination, swabs were collected at site of lesion from within tissue parenchyma under sterile conditions. Of the total 102 sheep lungs with clear gross lesions, 79 (77.45 %) lungs were found to harbor bacteria. For pathomorphological evaluation, only those lungs (79) that were found infected with bacteria were considered. Interstitial pneumonia was noticed in 21 (26.50 %) cases. Grossly, lungs were pale to red, heavy and firm, rubbery and cut surface had a meaty appearance and showed frothy exudate from the incised bronchi and bronchioles. Rib impressions were also observed over the costal surface of diaphragmatic lobes. Microscopically, the alveoli were distorted in shape, alveolar septae was thickened with infiltration of mononuclear cells and macrophages. At some places, the alveolar epithelium revealed foetalization with hyperplasia of type-II pneumocytes. In present study, bacteria isolated from lungs with interstitial pneumonia were Staphylococcus spp, Streptococcus spp, Pseudomonas spp, E. coli, Enterobacter spp and Klebsiella spp. mostly as mixed infections with no definite preference to single bacterial specie.