Effects of dietary aflatoxin on certain egg yolk parameters

Aflatoxicosis was induced in laying hens by incorporating graded amounts of aflatoxin into a commercial layer ration (0, 1.25, 2.5, 5.0, and 10.0 mug./g. of feed). After four weeks liver size and liver lipid were increased by aflatoxin while egg production and egg size were decreased (P less than 0.05). Total yolk weight and the yolk as percent of total egg weight were lowered (P less than 0.05). The dry weight and lipid content of the yolk were not affected. Yolk and plasma carotenoid concentrations were elevated (P less than 0.05). The data suggest that plasma and yolk lipids respond to the inhibition of lipid synthesis and transport from the liver by aflatoxin, but plasma and yolk carotenoids which are dietary in origin necessarily increase when egg production decreases during aflatoxicosis.