Opinion of the Scientific Panel on additives and products or substances used in animal feed (FEEDAP) on the efficacy and safety of the coccidiostat Koffogran

Abstract

SUMMARYKoffogran is a feed additive intended for control of coccidiosis, a debilitating protozoal infection in poultry. In common with a number of other coccidiostats, Koffogran is due for evaluation to comply with statutory requirements agreed at an EU-level. The European Commission asked the EFSA to evaluate the product and advise the Commission on its efficacy and safety. Within EFSA this task was allocated to the Scientific Panel on Additives and Products or Substances used in Animal Feed (FEEDAP Panel). The data provided in the dossier proved insufficient to give conclusive answers to the several questions raised by the European Commission.Koffogran contains 25 % nicarbazin as the active substance. Nicarbazin is a complex of the components 4,4'-dinitrocarbanilide (DNC) and 2-hydroxy-4,6 dimethylpyrimidine (HDP). It is effective as anticoccidial in chickens for fattening up to a maximum age of four weeks at a level of 100 to 125 mg nicarbazin kg -1 complete feed. However, a full assessment of the present day efficacy was not possible as an insufficient number of up-to-date trials had been carried out.Tolerance tests showed that Koffogran is safe for the chickens with a small, but acceptable margin of safety. Incompatibilities or interactions with feedingstuffs, carriers, other approved additives or medicinal drugs are not to be expected based on the known history of the additive.At feed level concentration nicarbazin had no activity against a range of pathogenic and non-pathogenic bacteria. Nicarbazin had no effect on the colonisation or excretion of Salmonella enteritidis. Therefore, nicarbazin can be considered to be safe as far as microbiological risk is concerned.Nicarbazin is absorbed to a large extent by chickens. The metabolic fate of nicarbazin shows that the DNC and HDP components of the complex are split and behave independently, the DNC moiety being mainly excreted in the faeces while the HDP mainly appears in the urine. The DNC metabolic fate has been established and the main metabolites identified in the excreta and tissues. DNC can be considered as the marker residue, but non identified metabolites represent more than 50 % of the total residues in the kidney and liver beyond a 3-day withdrawal period. Even if the metabolic fate of the HDP moiety of nicarbazin has not been investigated in depth, it appears that HDP is metabolised to a very limited extent and that the consumer is mainly exposed to HDP and not to its potential metabolites. The liver is the target tissue. Although the kinetics of HDP residues (or eventually the whole HDPderived compounds) are not available. Opinion on the additive Koffogran 2/40The submitted toxicological studies did not indicate a significant potential for target tissue toxicity, such as neurotoxicity, immunotoxicity, impaired fertility in mammals or endocrinemediated effects. The compound is unlikely to pose a carcinogenic risk. However, the toxicological dossier is far from satisfactory according to the present scientific standards. For developmental toxicity, e...

Perspectives and advances in probiotics and the gut microbiome in companion animals

“…Rinkinen [ 128 ] demonstrated that some Enterococcus faecium strains promoted the adherence of the zoonotic pathogen Campylobacter jejuni in the intestines of canines. Notably, the administration of E. faecium strain SF68 (deposited as strain NCIMB 10415), which originated from infant feces in 1968, reduced the occurrence of diarrhea in dogs and cats housed in animal shelters [ 45 ], and it has been verified that the strain may not cause any safety concerns for companion animals and their owners [ 129 - 131 ]. Due to these conflicting outcomes, stringent safety evaluations are required in a strain-specific manner with regard to probiotic use.…”