Extrahepatic bile duct malformation causing intrahepatic cholangiocellular proliferation with fibrosis in broiler chickens.

Malformation of the extrahepatic biliary tracts was observed in six of 88 enlarged, firm and discoloured livers collected at a slaughterhouse. Histologically, the six livers were characterized by diffuse cholangiocellular proliferation with fibrosis, extremely similar to the condition induced by bile duct ligation. These findings suggested that some cases of cholangiohepatitis in chickens are caused by biliary malformations with bile stasis.