The sole ST3870 isolate C09

also differed from the 4 ST88 isolates by serotype, hemolysis and antibiotic resistance profile. Figure 3 Genetic relationships of STEC isolates based on MLST. A) Genetic relationships of STEC sequence types (STs) from this study. Each circle represents a given ST with size proportional to the number of isolates. The colors for the slices of the pie represent places of isolates: Beijing city in green, Chongqing city in red and Guizhou province in purple. The numbers on connecting lines show the number of allelic difference between two STs. The number in a circle is the ST number. B) Minimal spanning click here tree of STs from this study, STs from the HUSEC collection and other human STEC STs. Ninety-three pig STEC isolates (in red) were compared to STs of HUSEC collection (in orange), human STEC STs (in green) and STs from other source that are identical to STs in our study (in blue) in E. coli MLST database. Each circle represents a given ST with the pie proportional to Verteporfin price number of isolates in a given ST from different sources. The numbers on connecting lines show the number of allelic difference between two STs. The number in a circle is the ST number. Isolates of the same STs generally

BIBF 1120 price showed the same or similar drug resistance patterns (Figure 2). All ST3628 isolates showed the same multi-drug resistance to 14 antibiotics. Similarly, isolates of ST206, ST953and ST1494 showed respective identical resistance profiles. All ST3629 isolates were resistant to tetracycline. However there existed variations of drug resistance within an ST. ST710 showed the most variability with resistance to 1 to 11 drugs. ST2514 which was isolated from C-X-C chemokine receptor type 7 (CXCR-7) all 3 regions also showed varied resistance profiles. Discussion Different prevalence of STEC in pigs were reported previously [24, 25, 27–29]. Kaufmann et al. [24] compared the STEC shedding rate in pigs at slaughter, which varied widely and ranged from 2.1% to 70% depending on the health conditions of the pigs and the detection method used. As shown in this study the anatomic sites sampled also affected the rate of isolation and consequently

affected the prevalence in the population reported. Fecal samples were commonly used [24–26]. In our study we sampled the small intestinal content, the colon content and the feces. The prevalence of STEC in the colon (47.24%) was almost 2.5 times higher than in feces (19.33%) (P < 0.05) and 4.4 times higher than in the small intestine (10.83%) (P < 0.05). STEC strains are thought to mostly colonize the colons of humans [30] and it is likely to be the same for pigs. In this study, 93 isolates were recovered from 62 of the 255 stx-positive samples, giving a culture positve rate of 24.31%, this result is similar to that of Botteldoorn et al.[28], in which STEC isolates were obtained from 31% of the stx PCR-positive pig samples.