Aflatoxin B1 residues in eggs of laying hens fed a diet containing different levels of the mycotoxin

The present study was carried out to evaluate the excretion of aflatoxin B-1 residues in eggs of young laying hens fed aflatoxin B-1-contaminated rations for 8 weeks. To this end, 96 twenty-week-old hens were randomly distributed into four experimental groups (24 birds per group) and given rations containing either 0 (controls), 100 mu g, 300 mu g or 500 mu g aflatoxin B-1/kg feed. Egg aflatoxin B-1 residues were determined by thin layer chromatography; two samples per treatment per week were used for analysis. Egg production and average egg weights were not affected (p < 0.05) in the groups receiving aflatoxin B-1-contaminated rations. Residues of aflatoxin B-1 were detected only in the eggs of hens given 500 mu g/kg feed, at levels that ranged from 0.05 to 0.16 mu g/kg (average: 0.10 mu g/kg). The results indicate that the feed to eggs aflatoxin B-1 transmission ratio was approximately 5000:1, emphasizing the importance of controlling aflatoxin levels in rations for laying hens.