Carry-over of deoxynivalenol into eggs of laying hens — Preliminary results

Carry-over of deoxynivalenol (DON) into eggs was investigated within the scope of a 16-week experiment with laying hens, in which the birds were fed a maize-based diet containing DON at 11.9 mg/kg dry matter. Eggs were collected during weeks 2, 4, 8, and 16. DON and its metabolite deepoxy-DON were analysed separately in freeze-dried yolk and albumen. Yolk was extracted with water and the extract was purified using an immunoaffinity column (IAC). Albumen was extracted with acetonitrile-water and the extract was pre-cleaned before applying an IAC. All albumen and some yolk samples were incubated with β-glucuronidase prior to extraction. DON and de-epoxy-DON were determined by high performance liquid chromatography (HPLC) with diode array detection (DAD). The detection limits of both toxins were 20 ng/g and 15 ng/g in freezedried yolk and albumen, respectively, corresponding to approximately 10 ng/g and 2 ng/g in fresh samples. The recovery of DON/de-epoxy-DON in spiked samples (50–200 ng/g) was 87/83% (yolk) and 87/77% (albumen) with coefficients of variation of 4–15%. Neither DON nor de-epoxy-DON were detected in any of the samples. In order to achieve lower detection limits, the methods are currently optimized. However, these preliminary results indicate that eggs do not contribute significantly to the dietary DON intake of the consumer. Presented at the 26^th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004