In a male, 6 months old, pig carcass, multiple whitish nodular lesions were observed in the lungs, parietal pleura, diaphragm and in the liver.

Although teh appearance was not of caseous necrosis the inspectors suspected of a tuberculosis case.

The histopathological study showed that it was a malignant round cell neoplasia: lymphosarcoma. In pigs, tuberculous lesions have a proliferative nature, rather than necrotic and, macroscopically, may resemble the aspect of a neoplasia. Therefore, it was necessary to rule out that it was an outbreak of tuberculosis. Tuberculous lesions in pigs can be caused by mycobacteria within the M.tuberculosis complex and M.avium.

Whitish nodular lesions in the parietal pleura and lung.

Whitish nodular lesions in the parietal pleura and lung.

Whitish nodular lesions in the liver.

Whitish nodular lesions in the liver.

Image of Histopathology of the liver showing a proliferation of round cells (upper left in blue color). At higher magnification (inset) one can observe neoplastic cells.

Image of Histopathology of the liver showing a proliferation of round cells (upper right, bluish). At higher magnification (inset) one can observe neoplastic cells.