Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Tai'an, China.
Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an, China.
Zoonoses Public Health. 2021 Aug;68(5):431-442. doi: 10.1111/zph.12831. Epub 2021 Apr 20.
The current study is undertaken to characterize the prevalence, genotypes distribution, antibiotic resistance and genetic diversity of Clostridium perfringens (C. perfringens) collected from different stages of a chicken production chain. In total, 579 samples from a broiler farm and 378 samples from the slaughterhouse were collected from a large-scale rearing and slaughter one-stop enterprise in Weifang, China, between June and July 2019, of which 30.40% of the samples from farm and 54.50% of samples from slaughterhouse were determined to be positive for C. perfringens, respectively. The contamination of chicken products was relatively serious, with the total positive rate of carcasses at 59.73%; the positive rate of carcass samples was the highest in the evisceration process, which might be the critical point of C. perfringens contamination. A total of 476 isolates of C. perfringens were recovered; and 99.58% of recovered isolates were identified as type A, with the remaining isolates being type G. Antimicrobial susceptibility testing revealed that 97.15% of the isolates showed multiple antibiotic resistance and 67.89% of them were resistant to at least five classes of commonly used antibiotics. Multilocus sequence typing results of 91 representative isolates showed that the isolates can be divided into 74 sequences types (STs); 40.66% of the isolates can be included into seven clonal complexes (CCs). Although most of the isolates were classified as type A, considerable genetic diversity was observed, with the Simpson's diversity index of ST up to 0.9902. Some isolates from farm stage and slaughter stage were distributed in the same ST or CC, indicating that chicken products may be contaminated by the same ST or CC of C. perfringens originated from the farm stage. The high contamination rates of chicken products and the widespread multiple antibiotic resistance of isolates indicated potential public health risks, control measures at rearing and slaughtering stage should be considered to reduce this risk.
本研究旨在描述从鸡生产链的不同阶段采集的产气荚膜梭菌（C. perfringens）的流行率、基因型分布、抗生素耐药性和遗传多样性。2019 年 6 月至 7 月，在中国潍坊的一家大型养殖和屠宰一站式企业，从一家肉鸡养殖场采集了 579 份样本，从屠宰场采集了 378 份样本，结果显示，养殖场样本中 30.40%和屠宰场样本中 54.50%为产气荚膜梭菌阳性。鸡肉产品污染较为严重，胴体总阳性率为 59.73%；在去脏过程中，胴体样本的阳性率最高，这可能是产气荚膜梭菌污染的关键点。共回收 476 株产气荚膜梭菌分离株；回收的分离株中 99.58%为 A 型，其余为 G 型。药敏试验结果显示，97.15%的分离株呈多重耐药，67.89%的分离株至少对 5 类常用抗生素耐药。91 株代表性分离株的多位点序列分型结果显示，分离株可分为 74 个序列型（ST）；40.66%的分离株可归入 7 个克隆复合体（CC）。虽然大多数分离株为 A 型，但遗传多样性较大，ST 的 Simpson 多样性指数高达 0.9902。来自养殖场和屠宰场的一些分离株分布在相同的 ST 或 CC 中，表明鸡产品可能受到来自养殖场阶段的同一 ST 或 CC 的产气荚膜梭菌污染。鸡肉产品的高污染率和分离株的广泛多重耐药性表明存在潜在的公共卫生风险，应考虑在养殖和屠宰阶段采取控制措施，以降低这种风险。
