[Identification and molecular subtyping of Campylobacter jejuni isolated from chicken carcass]

To characterize and investigate the molecular types of Campylobacter jejuni isolated from slaughter chicken carcass, which would provide scientific data for campylobacter food poisoning traceability.

Biochemical and molecular biological methods were used for screening and identification of isolates from chicken special monitoring networks. Campylobacter Genus-specific primers 16S rRNA and species-specific primers MapA and CeuE were designed to perform a multiplex PCR to identify these isolated strains. Pulsed-field gel electrophoresis (PFGE) was employed to type Campylobacter jejuni isolates by digesting with restriction endonuclease Sma I and Kpn I respectively. Fingerprints of these isolates were analyzed by the software BioNumerics.

72 out of 81 isolates were confirmed as Campylobacter jejuni by biochemical test combined with PCR. 48 patterns were obtained from PFGE with Sma I and Kpn I. 72 isolated strains were divided into 13 clusters (A-M) according to 63.9% similarity by cluster analysis. Isolates from different provinces were distributed in 13 clusters and each cluster contained 1 to 11 patterns. The results showed that the 72 strain patterns distribution had complete regional homology, namely strains in the same pattern were from a single province.

The comprehensive analysis of Sma I and Kpn I results may help improving the resolution of PFGE, increasing the accuracy of typing and reliability of traceability.