Scientific Opinion on safety and efficacy of Cygro? 10G (maduramicin ammonium α) for chickens for fattening

摘要

Cygro? 10G is a coccidiostat for chickens for fattening containing 10 g of maduramicin ammonium α/kg additive. The highest proposed dose (6 mg/kg) appeared near to the intolerance level. Maduramicin ammonium α can inhibit the growth of some Gram‐positive micro‐organisms, but measurable adverse effects on the overall gut flora are unlikely. Maduramicin was excreted rapidly in chickens, mainly unchanged. O‐demethylation represented the main metabolic pathway in chickens and rats. Tissue residue kinetics indicate a rapid decline in all tissues. Liver was the target tissue; maduramicin the marker residue in all tissues. Maduramicin ammonium α was not mutagenic. It was concluded from chronic toxicity/carcinogenicity studies in rats and mice that maduramicin ammonium α is not a carcinogen. The lowest NOAEL of 0.1 mg/kg bw/day was found in a chronic rat study and in a multi‐generation study in rats. An ADI of 1 μg maduramicin/kg bw was derived, applying an uncertainty factor of 100, which corresponds to an acceptable daily exposure of 60 μg per person. After a three‐day withdrawal, human exposure to maduramicin residues complied with the ADI (42 %). MRLs of 0.15 mg maduramicin/kg liver and skin/fat, 0.1 mg/kg kidney and 0.03 mg/kg muscle were proposed. Maduramicin ammonium α showed a high systemic toxicity after dermal application. Although Cygro? 10G did not show skin and eye irritating or skin sensitising properties, any direct dermal contact with the additive must be avoided. Cygro? 10G has a low dusting potential and from the result of acute inhalation toxicity study it was described as harmful if inhaled. Consequently, inhalation should be minimised. Cygro? 10G at the maximum dose of 6 mg maduramicin/kg feed does not pose a risk for the environment. The dose‐range, 5–6 mg maduramicin/kg complete feed is effective in controlling coccidiosis in chickens for fattening.