EN 16936:2017

European foreword
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Apparatus
6 Sample preparation
7 Measurements
8 Determination of concentrations
9 Precision
10 Test report
Annex A (informative) - Preparation of bacterial suspensions
Annex B (informative) - Procedure for the additional
        identification of interfering antibiotics
Bibliography

This European Standard presents a method describing the screening on the antibiotics tylosin, virginiamycin, spiramycin, bacitracin-zinc and avoparcin at sub-additive levels in complete feeding stuffs and milk replacers by a microbiological 3-plate test.The limit of detection of the method is 1 mg/kg for avoparcin, tylosin, spiramycin and virginiamycin, and 5 mg/kg for zinc bacitracin. The presence of other (veterinary) antibiotics may interfere with the method.Furthermore, high concentrations of metals (Cu, Zn) may interfere. The method should be used as a qualitative screening method. Positive results can be analysed further by TLC; for confirmatory purposes LC-MS is required [1].A lower limit of detection for zinc bacitracin (3 mg/kg) is achievable (see Table 2), but should be established with an in house validation first.