Background <p>Bacterial bronchopneumonia is a challenging condition to diagnose in dogs due to the variable clinical presentations and the nonspecific thoracic radiographic findings.</p> Aims <p>This study aimed to descriptively characterize the diagnostic utility of transtracheal wash cytology and culture, along with the clinical, arterial blood gas and radiographic alterations, in the dogs diagnosed with bacterial bronchopneumonia.</p> Clinical presentation <p>Seven affected dogs were presented with bilateral nasal discharge (mucopurulent (n=3), serous (n=2), absent (n=2)), moist or productive cough (marked (n=4), moderate (n=3)), tachypnea (n=3), dyspnea (n=3), anorexia (n=3), lethargy (n=3), fever (n=1), dehydration (n=4), weight loss (n=2), exercise intolerance (n=5) and presence of tracheal sensitivity in 6 dogs. On chest auscultation abnormal lung sounds were heard in all the dogs with apparent crackles in 2/7, wheezes in 2/7 and increased bronchovesicular sounds in 3/7 animals.</p> Methods <p>Complete blood count, serum protein levels, plasma fibrinogen, arterial blood gas analysis, thoracic radiography and transtracheal wash was taken for the cytological interpretation and culture sensitivity testing in all diseased dogs.</p> Results <p>The present study showed relative or/and absolute neutrophilia in the affected dogs. Hypoalbuminaemia (5/7) and hyperfibrinogenaemia (6/7) were recorded on biochemical examination along with hypoxemia (7/7) on blood gas analysis. Thoracic radiography showed presence of mixed interstitial and alveolar pattern in 5 dogs, only interstitial in 1/7 and typical alveolar pattern in only 1/7 dog. Transtracheal wash cytology revealed markedly increased cellularity with majority of degenerated and non-degenerated neutrophils along with few macrophages, occasional sloughed epithelial cells and curschmann’s spirals indicative of long-standing chronic inflammation along with positive culture reports.</p> Conclusion <p>So the study descriptively characterizes the bacterial bronchopneumonia in dogs using clinical, arterial blood gas, radiographic, tracheal wash cytology and bacteriological findings. Among these, tracheal wash cytology appeared to provide useful supportive diagnostic information for identifying the airway inflammation and associated bacterial infection in the affected dogs. To the authors’ knowledge, this is the first descriptive report from India evaluating transtracheal wash cytology in canine bacterial bronchopneumonia cases.</p> Clinical trial number <p>Not applicable.</p>