DUCKLINGS WITH AFLATOXIN POISONING

The toxicity associated with certain samples of groundnut has been shown to be due to aflatoxin (12), a metabolic product of the fungus Aspergillus flavus. Sensitivity to aflatoxicosis has been highest among ducklings several weeks old (1). The biological assay of aflatoxin is also based on its hepatotoxic effect in day-old ducklings (11). The gross lesions most typical of aflatoxicosis have been a moderate enlargement and necrobiotic fatty infiltration of the liver. Histologically the condition is characterized by swelling of parenchymal cells and their nuclei, fatty degeneration of liver cells, and proliferation of the biliary duct epithelium (1,3,13,14). In practice, aflatoxin poisonings are diagnosed by histo logical examination of the liver. In the livers of ducklings 10- 20 days old we observed, besides, the well-known typical lesions and other phenomena which seemed to be related with aflatoxin poisoning. In histological sections stained with Sudan III to demonstrate fatty degeneration of liver cells, as well as in unstained smear, anisotropic phenomena were detected by polarization microscopy. In both kinds of preparations appeared masses of small crystals filling the entire field of vision. Depending on the position of the condenser, they assumed a yellow, green, or blue color over a dark or red background. No similar phenomena were observed in specimens from the livers of healthy ducks 10 - 20 days old processed in the same ways. Also, in the livers of ducklings dead of aflatoxicosis, anisotropy was demonstrable only in Sudan-stained sections or rather in unstained smears of liver tissue. This implied the responsibility of lipid-like substances for the phenomenon. In this paper we describe further studies performed to clarify the cause and importance of anisotropy in association with the aflatoxin poisoning of ducklings.