Coccidiostats in animal production: residue depletion, and cross-contamination in the feed-food chain.

Coccidiostats are used in animal production to control infections caused by Eimeria spp., particularly in poultry. While these compounds are effective in preventing coccidiosis and maintaining production efficiency, their use raises concerns regarding the occurrence of residues in the feed-food chain. This review summarises current knowledge on residue occurrence, transfer to food of animal origin, and depletion of coccidiostats following authorised use. Special attention is given to cross-contamination during feed manufacturing, which represents one of the sources of unintended exposure of non-target animals. Available studies show that carry-over of coccidiostats into non-target feed is relatively common and may lead to residues in products such as eggs, meat, and milk. Coccidiostats residues appears to be strongly matrix-dependent, with eggs showing the highest and most predictable transfer rates. Depletion studies indicate that residues in tissues generally comply with established maximum residue limits when recommended withdrawal periods are respected. In contrast, the residues in eggs may persist longer due to the physiology of egg formation. Monitoring data from the European Union demonstrate a decrease in non-compliant samples over the past decade, indicating the effectiveness of the current regulatory framework. Nevertheless, continued monitoring, improved feed safety practices, and risk assessments remain essential to ensure consumer protection while maintaining the benefits of coccidiostat use in modern animal production systems.