The cross-contamination of non-target feeds with coccidiostats may result in the occurrence of their residues in food of animal origin. To assure food safety, maximum levels (ML) of coccidiostats have been set for both feed and food. However, scientific data are not available on the transfer of some coccidiostats from feed into food. This experiment was therefore designed to verify, whether the administration of compliant semduramicin-contaminated feed could cause the occurrence of violative residues of coccidiostats in eggs. The laying hens received feed containing 0.27±0.034mg/kg of semduramicin (ML=0.25mg/kg). Semduramicin residues were detected in whole eggs after two days of administration of semduramicin-containing diet. A plateau level was achieved (16.1±5.19μg/kg, mean±SD) with the concentrations significantly exceeding the maximum level of semduramicin in eggs (2μg/kg). The results of this experiment might be a signal for the revision of the ML value.