Methods for identification and assay of virginiamycin in animal feeds

Abstract

Methods for identification and assay of virginiamycin in feeds are proposed. The specific identity test is based on paper chromatography followed by bioautography with Corynebacterium xerosis(NCTC 9755). The assay is carried out by a paper disc agar-diffusion method with the same organism as the test organism. Some specific requirements for the assay of virginiamycin are discussed, with particular reference to the marked synergism between its components, the M and S factors.