Scientific Opinion on safety and efficacy of Cycostat® 66G (robenidine hydrochloride) for rabbits for breeding and fattening

Cycostat® 66G is a coccidiostat for rabbits for breeding and fattening, containing 66 g robenidine hydrochloride/kg feed. The FEEDAP Panel concludes that feed concentrations ≤ 66 mg robenidine hydrochloride from Cycostat® 66G/kg complete feed are safe for breeding does. The margin of safety is about three. This conclusion can be extrapolated to rabbits for fattening. Robenidine hydrochloride is not genotoxic. Chronic studies in rats and dogs did not allow to determine a NOAEL but gave no indications of the tumorigenicity of robenidine hydrochloride. The lowest NOAEL of 11 mg/kg bw/day could be derived from the tolerance study in breeding does. An ADI of 0.11 mg robenidine hydrochloride/kg bw, equivalent to 6.6 mg for a 60 kg adult, is proposed, applying a safety factor of 100. Robenidine is the marker residue. No MRLs would normally be required. If MRLs should be set for control purposes they should concern only the liver and kidney (0.2 mg robenidine/kg tissue each). Robenidine hydrochloride is not a skin or eye irritant and not a skin sensitiser. The inhalation LC50 (>5.2 mg/L) is higher than LC50 values which require classification under Regulation (EC) No 1272/2008. The use of Cycostat® 66G at the recommended dose range does not pose a risk for the environment. Robenidine hydrochloride at 66 mg/kg feed has a potential to control coccidiosis in breeding does and rabbits for fattening. 50 mg robenidine hydrochloride/kg has been demonstrated to be efficacious only in breeding does. Sensory quality of rabbit meat is ensured after a five-day withdrawal period.