RESUMEN
Seventy two cattle with bacterial pneumonia and twelve healthy cattle were studied in detail for haemato-biochemical examination, radiography and tracheobronchoscopy. Haematobiochemical examination revealed leukocytosis with neutrophilia. Radiographic examination showed increased pulmonary infiltration. Tracheobronchoscopic examination of affected animals revealed inflammation, haemorrhage, mucus to mucopurulent exudates in nasal cavity, trachea, bronchi and bronchioles. Bronchoalveolar lavage (BAL) collected through endoscope was subjected to cytology and cultural examination. Cytology of the affected animals showed increased total cell counts and predominant neutrophils. Pasteurella multocida, Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli were isolated from BAL and confirmed with PCR studies