Scientific Opinion on safety and efficacy of Cygro® 10G (maduramicin ammonium α ) for chickens for fattening
Cygro® 10G is a coccidiostat for chickens for fattening containing 10 g of maduramicin ammonium /kg additive. The highest proposed dose (6 mg/kg) appeared near to the intolerance level. Maduramicin ammonium 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 was not mutagenic. It was concluded from chronic toxicity/carcinogenicity studies in rats and mice that maduramicin ammonium 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 g maduramicin/kg bw was derived, applying an uncertainty factor of 100, which corresponds to an acceptable daily exposure of 60 g 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 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.