Poder discriminatório das tecnicas de RAPD (Random Amplified Polymorphic DNA) e PFGE (Pulsed-field gel electrophoresis) para diferenciar Campylobacter jejuni isoladas de carcaças de frangos

Abstract

Campylobacter jejuni is recognized as the main agent that causes foodborne gastroenteritis in the US and Europe. Chicken meat is the main vehicle of transmition of disease to humans. One of the ways to epidemiologically evaluate the microorganism are the genotyping techniques such as PFGE and RAPD. However, there are few studies comparing techniques in terms of discrimination efficiency of the strains. The aim of this study was to evaluate the genetic similarity of 44 strains of C. jejuni isolated from carcasses of broiler chickens under system of federal inspection (SFI). The isolated samples were genotyped by the PFGE methods using the SmaI enzyme and RAPD using primers 1290 and HLWL, alone and combined, for the subsequent photodocumentation for computational analysis, totalizing four dendrograms. The analyzes of the dendrograms formed were based on the comparison of the different profiles, pulses/clusters and clones formed. The results showed that eight distinct profiles and only one cluste/pulsetype in common were identified for the four tests. The other strains showed totally different behavior, making it difficult to compare RAPD and PFGE. In addition, it became clear that primer 1290 does not show good discriminatory power, proving the need to use more than one primer in this technique. In general, the RAPD presented greater discriminatory power, but it is worth considering that the technique has low reproducibility and that PFGE is widely recognized as a gold standard.