Deposition and Depletion of Five Anticoccidials in Eggs

Abstract

Anticoccidials are compounds that are widely used as feed additives to prevent and treat coccidiosis. They are licensed for use in a prescribed concentration and during a certain time interval for broilers and pullets but not for laying hens. It was shown in the past that carry-over at the feeding mill is found to be the main reason for the presence of residues in eggs. An animal experiment was set up to investigate the effect of carry-over at the feeding mill on the presence of residues of anticoccidials in eggs. For the compounds diclazuril, robenidine, halofuginone and nicarbazin in combination with narasin, two concentration levels were tested: the maximum allowed concentration for broilers (100%) and a concentration corresponding to 5% carry-over during feed preparation. Also dimetridazole was included in the experiment but only at one concentration level. Eggs were sampled during treatment (14 days) and for a period of 30 days after withdrawal of the anticoccidial-containing feed. Residues were determined, and deposition and depletion curves were generated. Analyses were performed by ELISA and LC-MS/MS. For all compounds, substantial residues could be found in the 5% groups, which points out the risk of carry-over at the feeding mill. The distribution of the residues between egg yolk and white was determined by analyzing both fractions.

Feed additives and veterinary drugs as contaminants in animal feed – the problem of cross-contamination during feed production

“…Overall, the author determined transfer rates of between 0.005% for tylosin and 1.54% for sulfadimidine. Depletion data for various coccidiostats into egg were also investigated in detail by Mortier et al (2005b). Laying hens were given feed containing various coccidiostats, ranging from 1 mg kg −1 for diclazuril up to 40 mg kg −1 for narasin and nicarbazin (corresponding to the statutory levels).…”

Emerging safety and quality issues of compound feed with implications for human foods

“…Yet, coccidiostat residues in eggs at concentrations higher than the tolerance level established in Directive 2009/8/EC are reported (Cannavan et al, 2000;Kennedy et al, 1996Kennedy et al, , 1998Mortier et al, 2005;Yakkundi et al, 2002). These unwanted residues in eggs come from accidental contamination of layer-diets in animal feed mills via carry-over from one batch of feed to another.…”

“…These unwanted residues in eggs come from accidental contamination of layer-diets in animal feed mills via carry-over from one batch of feed to another. In fact, in some feed mills, as much as 15% carryover from one batch to another has been reported (Mortier et al, 2005). Carryover can also occur during transport of feed to the farm (Kan and Meijer, 2007).…”

Cross-contamination of non-target feedingstuffs by diclazuril authorised for use as a feed additive - Scientific opinion of the Panel on Contaminants in the Food Chain

“…Deposition and depletion of diclazuril in eggs have been studied recently (Mortier et al, 2005d). Two concentration levels were tested: the authorised concentration for chickens for fattening (1 mg/kg feed) and a concentration corresponding to 5% carry-over during feed preparation (50 µg/kg feed).…”