Banned antibacterial growth promoters in animal feed: Collaborative trial on the liquid chromatography–tandem mass spectrometry method developed in the feedstuffs-radius project

A chemical confirmation method for the identification and quantification of five banned antibacterial growth promoters (AGPs) in animal feed was developed and in-house validated as part of the European Feedstuffs-RADIUS project [1]. To complete the validation process a collaborative trial was performed by eleven laboratories within the European Union (EU) using the developed method. Laboratories were supplied with six animal feed samples. None of the participants reported any false non-compliant results on these samples. Neither where there any false compliant results for four out of five compounds. These data proved the procedure to be robust and an excellent means of controlling misuse of the banned antibacterial growth promoters. During a small feed survey, a selection (n = 614) of animal feed samples were screened with a multi-antibiotic ELISA method [2] that was developed in the same EU project and non-compliant samples were submitted to liquid chromatography-tandem mass spectrometry (LC–MS/MS) confirmation. The results from this confirmatory analysis indicated that the LC–MS/MS method will be a valuable tool in helping to determine the origin of the detected antibacterial compounds and that animals are still receiving tylosin in concentrations that are in the same range as the now banned AGP concentrations.