Safety and efficacy of Monimax® (monensin sodium and nicarbazin) for turkeys for fattening

Monimax® is considered safe for turkeys for fattening at the highest use level of 50 mg monensin sodium and 50 mg nicarbazin/kg complete feed. The margin of safety is about 1.5. The simultaneous use of Monimax® and certain antibiotic drugs (i.e. tiamulin) is contraindicated. Nicarbazin (equimolar complex of dinitrocarbanilide (DNC) and 2-hydroxy-4,6-dimethylpyrimidine (HDP)) has no antimicrobial activity. For both compounds of Monimax®, the metabolic pathways in the chicken are similar to those in the turkey and rat. Monimax® does not represent a genotoxic risk. No safety concerns would arise from the nicarbazin impurities p-nitroaniline and methyl(4-nitrophenyl) carbamate. The lowest no observed effect level (NOEL) identified for monensin sodium in a developmental study in rabbits was 0.3 mg monensin sodium/kg body weight (bw) per day for maternal toxicity in rabbits. The lowest no observed adverse effect level (NOAEL) identified in a 52-week study in rat using DNC + HDP was 20 mg DNC + 8 mg HDP/kg bw per day. No significant interaction between monensin sodium and nicarbazin is expected from toxicological studies. The use of Monimax® at the highest proposed dose will not pose a risk to persons consuming animal products from treated turkeys for fattening. No withdrawal time is required for Monimax® in turkeys for fattening. Residue data comply with the established maximum residue limits (MRLs) for monensin and DNC. Monensin sodium presents a hazard by inhalation and may also be associated with dermal toxicity. Monimax® is not a skin irritant; however, no data are available for the eye irritation potential of monensin. Monimax® is not a skin sensitiser. Based on the available data, the FEEDAP Panel cannot conclude on the safety of Monimax® for the environment. Monimax® has the potential to control coccidiosis in turkeys for fattening at a minimum concentration of 40 mg monensin sodium and 40 mg nicarbazin/kg complete feed.