Evaluation of PCR-based fingerprinting comparatively to the RFLP-PFGE for discrimination of Salmonella sp. isolated from slaughtered pork

Abstract

Effective epidemiological surveillance and control of Salmonella sp. requires accurate and expeditious genetic typing methods. In the present study, rapid PCR-based methods (ERIC-PCR, M13-PCR and RAPDs) were applied to 73 Salmonella sp. isolates, and the results compared with those previously obtained by RFLP-PFGE (Salmonella gold standard genotyping method), in order to evaluate their discriminatory ability. Results were very diverse among the primers used and, for each primer, the performance level was variable among the different serotypes. ERIC-PCR and RAPD with OPC19 was inefficient for Salmonella sp. discrimination beyond the serotype level. In opposite, M13-PCR, OPC15-RAPD and OPB17-RAPD allowed intraserotype discrimination that, in general, were less discriminative than RFLP-PFGE, indicating that should not be used as a unique typing method in epidemiological studies. Nevertheless, in particular situations, these PCR methods, which are faster and less expensive than RFLP-PFGE, could offers an attractive choice as a preliminary screening of the isolates to reduce the number of suspicious isolates that should be subsequently typed with a more discriminative and accurate methods such as RFLP-PFGE.