Pathogenicity of an isolate of Aspergillus flavus in chickens

Cockerels aged 8 days were each given intraperitoneally a 1 ml suspension of Aspergillus flavus grown on Sabouraud's dextrose agar containing 10(6) colony forming units per ml. No clinical signs were observed but mortality was 37.5%. Liver and kidney were enlarged at necropsy. Granulomatous nodules were found in the serosa and lung parenchyma up to day 16 post-infection but by day 30 post-infection tiny nodules persisted only at the site of inoculation. Periodic acid-Schiff stained sections of the serosa, lung, kidney, liver, spleen and bursa of Fabricius showed the fungus in only the serosa and lungs. There was fibrosis of the hepatic portal canal, congestion and hyperplasia of the bile ducts. In the kidney there was degeneration of mainly the epithelium of proximal convoluted tubules followed by generalised pyknosis. Bursa and spleen showed lymphocytic depletion. The fungus was reisolated from the nodules up to day 16 post-infection. The above observations appear to describe a condition of concurrent mycotoxicosis and aspergillosis due to Aspergillus flavus.