BS EN 17299:2019 Animal feeding stuffs. Methods of sampling and analysis. Screening and determination of authorized coccidiostats at additive and 1 % and 3 % cross-contamination levels, and of non-registered coccidiostats and of one antibiotic at sub-additive levels, in compound feed with High Performance Liquid Chromatography. Tandem Mass Spectrometry detection (LC-MS/MS)