Monensin carry-over into unmedicated broiler feeds

European Union Member States are now required to monitor poultry meat for t he presence of coccidiostat residues. Among other factors contributing to t he production of residue-free food is the ability of animal feed manufactur ers to produce medication-free feedstuffs, ensuring the proper observance o f withdrawal periods prior to slaughter. Carry-over of medication was inves tigated in a local poultry feed mill that was using monensin as its princip al coccidiostat for broilers. Monensin, at levels in excess of 5% of the th erapeutic dose (approximately 110 mg kg(-1)), was present in 22.5% of 40 wi thdrawal feeds. Subsequent studies in the mill indicated that most of the c ontamination occurred during the processing of feeds after the mixing stage . The mill altered its manufacturing process as a result of this study. The consequence of this was that the incidence of monensin withdrawal feeds, a t levels greater than 5% of the therapeutic dose, fell from 22.5 to 2.5%. T his collaborative study has helped the feed compounder to produce mon effec tive withdrawal feeds, thereby reducing the potential exposure of consumers to unwanted residues of monensin in poultry meat.