Periacinar liver fibrosis caused by Tephrosia cinerea in sheep.

Tephrosia cinerea has been associated with ascites and liver fibrosis in sheep in Brazil. The dried plant was fed ad libitum to three sheep for 55-80 days. Three additional sheep were used as controls. All the treated sheep presented with hypoalbuminemia and increased γ-glutamyltransferase and aspartate aminotransferase activities. Anorexia, apathy, rough coat, ascites, and emaciation were observed after 45-60 days of feeding with T. cinerea. At necropsy 55-80 days after feeding of the plant commenced, the treated sheep had ascites, hydrothorax and hydropericardium, and their livers were firm and whitish, with a nodular surface. Histologically, the main hepatic lesions were periacinar fibrosis associated with hemorrhages and necrosis. On electron microscopy, a severe swelling of sinusoidal endothelial cells, frequently obstructing the lumen of the sinusoid was observed. The space of Disse was compressed by the swollen endothelial cells and microvilli usually present on the surface of hepatocytes adjacent to the space of Disse were not apparent. Dense bundles of collagen fibers were present in the spaces of Disse and within the sinusoids between profiles of swollen endothelial cells. It is concluded that T. cinerea causes periacinar fibrosis, similar to poisoning by Galenia africana in sheep and goats and veno-occlusive disease in different species.