Aflatoxin and its metabolites in tissues from laying hens and broiler chickens fed a contaminated diet

Two groups of 32 hens and broiler chickens were contaminated with 2.5 and 5 mg of aflatoxin (AF) kg−1 feed for a period of 32 days. During this contamination 16 birds were sacrificed and aflatoxin and its metabolites were detected using thin‐layer chrotnatography and fluorescence densisometry. The tissues analysed (liver, muscle, kidney, gizzard and eggs) gave a wide range of concentrations, the lowest was found in ben muscle (0.05 μg kg−1 of AFB1) and the highest in gizzards from the 5 mg kg−1 group of the hens (9.01 μg kg−1 of AFB1). Metabolites of AFB1, AFM, and AFB2a appeared in the liver but not in other tissues. In broiler's tissues, the following metabolities were isolated: AFM1 and AFB2a, in liver, aflatoxicol in muscle and AFM1 and AFB2a in kidneys, all having concentrations lower than AFB1. Aflatoxicol was isolated from one egg sample (0.32 μg kg−1). For both types of birds, aflatoxin clearance time was only 24 h for muscle and kidneys. In livers from the 5 mg kg−1 group, AFM1 and AFB2a were still found 4 days after removal of the contaminated feed. In eggs and gizzards, aflatoxin residue was still detected on the 8th day of the clearance period although in low quantities. In the broiler's gizzards, clearance time was only 24 h. These results suggest that aflatoxin transfer to edible tissues is very small and the danger of contaminations to humans is also very small, except in the case of gizzards.