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We report that Clostridium perfringens was present in 23.1% (130/562) of broiler chickens and 15.1% (38/252) of retail chicken meat samples in central China. Among 168 isolates, type A was the preponderant genotype, and 3% of isolates were positive C. perfringens enterotoxin (cpe). Among different sources, the prevalence was higher in free-range chickens compared to chickens from intensive poultry farms, but with lower proportions of antimicrobial resistance.

Background Campylobacter species are the major food-borne pathogens which could cause bacterial gastroenteritis in humans. Contaminated chicken products have been recognized as the primary vehicles of Campylobacter transmission to human beings. In this study, the prevalence of Campylobacter in retail chicken meat in Central China was investigated, and the isolates were further characterized using molecular approaches and tested for antibiotic resistance. Results A total of 302 chicken samples purchased from April 2014 to April 2015 were tested. The level of Campylobacter contamination was enumerated by most probable number-PCR (MPN-PCR). The Campylobacter positive rate was 17.2% (52/302), with bacterial count varying from 3.6 to 360 MPN/g in positive samples. A total of 52 Campylobacter strains, including 40 Campylobacter jejuni and 12 Campylobacter coli, were isolated from the positive samples. To examine the genetic diversity of the isolates, multilocus sequence typing (MLST) technology was applied, which identified 23 sequence types (STs) belonging to seven clonal complexes (CCs) and unassigned. Among them, the dominant CCs of C. jejuni included CC-353 and CC-464, and the dominant CCs of C. coli were CC-828 and CC-1150. Antibiotic resistance analysis showed that all of the isolates were resistant to norfloxacin and ciprofloxacin. 23 virulence-associated genes were tested in the isolates, which showed that the number of virulence-associated genes detected in the C. jejuni isolates ranged from 16 to 21, while in most of the C. coli isolates ranged from 12 to 16. Virulence-associated genes, flaA, flgB, flgE2, fliM, fliY and cadF were detected in all isolates. VirB11, however, was not detected in any of the isolates. Conclusions To the best of our knowledge, this is the first report on the contamination level and molecular biological features of Campylobacter strains in retail chicken meat in Central China, which showed high genetic diversity and remarkable antibiotic resistance. This study provided scientific data for the risk assessment and evaluation of Campylobacter contamination in retail chicken products. Electronic supplementary material The online version of this article (doi:10.1186/s13099-016-0132-2) contains supplementary material, which is available to authorized users.

Riemerella anatipestifer is an important bacterial pathogen associated with epizootic infections in waterfowl and various other birds. Riemerella anatipestifer strain RA-JLLY is an avirulent strain, isolated from the brain of an old duck in Hubei province, China. Here, we report the genome sequence of this species.

The aim of this study was to develop a one-step real-time reverse transcription-polymerase chain reaction assay using the minor groove binding probe (MGB rRT-PCR) for rapid and quantitative detection of classical swine fever virus (CSFV). The method, which targets the 5'-nontranslated region (5'NTR) of the viral genome, detected all CSFV isolate tested, but not heterologous pathogens. Using an in vitro transcript of the 5'NTR as a quantitative standard for the CSFV genome copy number, the assay had a detection limit of 10 copies/reaction, and the standard curve had a linear range from 10 to 10(7) copies/reaction, with good reproducibility. As determined by an end-point dilution comparison, in most case, the sensitivity of the MGB rRT-PCR was approximately 10-fold higher than that of virus isolation and the rRT-PCR using the standard Taqman probe (standard rRT-PCR). The agreement between the MGB rRT-PCR and standard rRT-PCR, or virus isolation was 93.3% and 76.7%, respectively, when detecting 261 field samples. Due to its rapidity, high specificity and sensitivity, the MGB rRT-PCR assay provides a valuable tool for diagnosis and molecular studies of CSFV biology.