IDENTIFICATION OF E. COLI O157 IN A BOVINE MILK FARM BY MULTIPLEX REAL-TIME PCR

Abstract

Law provisions about direct sell of raw bovine milk require VTEC O157 monitoring in bovine milk farms (milk and faeces). It has been showed that culture-based methods used for this scope, besides being cumbersome and time-consuming, may be also less sensitive, compared to molecular approaches. In this study, a multiplex Real-Time PCR, able to identify VTEC O157, Salmonella spp and Listeria monocytogenes, has been used to analyse milk, filter, sewage and stool samples from a milk farm, in comparison with standard OIE methods. The performances of the molecular protocol have been preliminary assessed with lyophilized samples from proficiency testing VLA, showing 100% accordance. Results from field samples indicated the absence of the pathogen in milk, and the higher sensitivity of Real-Time PCR with other matrices, suggesting its potential use for fast VTEC O157 identification.

Keywords

• Raw milk, multiplex Real-Time PCR, proficiency testing.