Jiang Yanfen, Ma Yinghui, Liu Qianqian, Li Tianmei, Li Yiming, Guo Kangkang, Zhang Yanming
College of Veterinary Medicine, Northwest A&F University, 712100, Yangling, Shaanxi, China.
College of Veterinary Medicine, Northwest A&F University, 712100, Yangling, Shaanxi, China.
Food Microbiol. 2022 Feb;101:103887. doi: 10.1016/j.fm.2021.103887. Epub 2021 Aug 24.
The purpose of this study was to investigate the distribution and specify the transmission and cross-contamination of Clostridium perfringens (C. perfringens) in the beef slaughtering and butchering process. The prevalence of 21.2% (150/708) yielded 208 isolates of C. perfringens, including 80.8% type A and 19.2% type D, 0.4% (3/708) samples carried both type A and D strains, and 72.5% type D isolates carried both cpe and atyp.cpb2 genes. C. perfringens were identified through the whole slaughtering process but no type F (cpe and cpa isolates) was found. 69 isolates were further analyzed and classified into 28 PFGE genotypes and clade I contained 94.2% isolates and 24 PFGE genotypes, which showed the genetic diversity and epidemic correlation. Our study traced C. perfringens contamination along the handling processes and showed a gradually ascending contamination rate during the whole process, revealing widespread cross-contamination from the feces and hides of slaughtered cattle to the carcass in the slaughtering workshop, so as from tools and personnel to meat of the cutting workshops. Strains from different slaughterhouses (regions) have high homology, and type A is the predominant toxinotype. It is necessary to monitor and control several key points of cross-contamination during slaughtering process to reduce a risk of C. perfringens infection.
本研究的目的是调查产气荚膜梭菌在牛肉屠宰和分割过程中的分布情况，并明确其传播和交叉污染情况。21.2%（150/708）的流行率产生了208株产气荚膜梭菌分离株，其中80.8%为A型，19.2%为D型，0.4%（3/708）的样本同时携带A型和D型菌株，72.5%的D型分离株同时携带cpe和atyp.cpb2基因。在整个屠宰过程中均鉴定出了产气荚膜梭菌，但未发现F型（cpe和cpa分离株）。对69株分离株进行了进一步分析，分为28个PFGE基因型，其中I分支包含94.2%的分离株和24个PFGE基因型，显示出遗传多样性和流行相关性。我们的研究追踪了产气荚膜梭菌在处理过程中的污染情况，结果显示在整个过程中污染率逐渐上升，揭示了屠宰车间中从屠宰牛的粪便和皮毛到胴体，以及分割车间中从工具和人员到肉类的广泛交叉污染。来自不同屠宰场（地区）的菌株具有高度同源性，且A型是主要的毒素型。有必要在屠宰过程中监测和控制交叉污染的几个关键点，以降低产气荚膜梭菌感染的风险。
