Occurrence of granulomas in bovines: an abattoir-based study

The present study was carried out to record the occurrence of naturally occurring granulomas in cattle and buffaloes. Tissues grossly suspected for granulomas were collected from 336 out of 1600 (21%) abattoir cases. The gross features ranged from focal necrosis to large caseated masses, hard nodules, growths and abscesses. Histopathologically, 102 tissue samples (6.38%) were ascertained as granulomas. Majority of the granulomas were found in the liver 42 (41.18%), followed by lungs 22 (20.59%), lymph nodes 11 (10.78%), kidneys 6 (5.88%) and 14 (13.73%) as subcutaneous nodules/growths. Solitary cases were found in tongue, muscle, and urinary bladder, whereas 4 granulomas (3.92%) were found in body cavities. Based on the cellular component, the granulomas were categorized as epithelioid (53%), eosinophilic (37%) and suppurative (10%). Employing special staining techniques, the possible etiology of 75 granulomas could be identified. Among these, 70 granulomas (68.63%) were of infectious nature (parasitic 37 (36.28%), bacterial 32 (31.37%), and fungal 1(0.98%)). Non-infectious granulomas 5 cases (4.90%) included two lipid granulomas (1.96%), two granulomas (1.96%) associated with neoplasms and one (0.31%) associated with renal calculi. In 27 (26.47%) cases, the etiology of the granuloma could not be established and were categorized as granulomas of unknown etiology.