Bardasi Lia, Taddei Roberta, Fiocchi Ilaria, Pelliconi Maria Francesca, Ramini Mattia, Toschi Elena, Merialdi Giuseppe
Institute for Experimental Veterinary Medicine of Lombardy and Emilia Romagna, Bologna, Italy.
Ital J Food Saf. 2017 May 9;6(2):6584. doi: 10.4081/ijfs.2017.6584. eCollection 2017 Apr 13.
During the years 2015-2016, 83 faecal samples were collected at slaughter from pigs reared in farms located in Central-Northern Italy. During the years 2014-2016 a total of 562 pork products [465 not-readyto-eat (NRTE) and 97 ready-to-eat (RTE) products] were collected from retail outlets, large retailers and processing plants. The samples were analysed according to ISO TS 13136:2012. Out of 83 swine faecal samples, 77 (92.8%) resulted stx-positive by real time polymerase chain reaction (PCR), 5 and 1 Shiga toxin-producing (STEC) strains were isolated. Among the 465 NRTE samples, 65 (14.0%) resulted stx-positive by real time PCR and 7 STEC strains were isolated. The gene was detected more frequently than the gene both in faecal samples (90.4 vs 8.4%) and in NRTE pork products (13.3 vs 1.3%). All the RTE samples included in the analysis resulted negative. Among the samples resulted positive for and genes, serogroup-associated genes were detected at high frequency: O26 resulted the most frequent in faecal samples (81.3%) and O145 in pork products (88.1%). The O157 serogroup resulted positive in 83.3 and 78.1% of pork products and faecal samples, respectively. Despite the frequent detection by real time PCR of genes indicating the possible presence of STEC strains belonging to the six serogroups, the bacteriological step did not confirm the isolation of any such strains.
在2015年至2016年期间，从意大利中北部农场饲养的猪身上采集了83份粪便样本。在2014年至2016年期间，从零售商店、大型零售商和加工厂共采集了562份猪肉产品[465份即食（NRTE）产品和97份即食（RTE）产品]。根据ISO TS 13136:2012对样本进行分析。在83份猪粪便样本中，77份（92.8%）通过实时聚合酶链反应（PCR）检测为stx阳性，分离出5株和1株产志贺毒素（STEC）菌株。在465份NRTE样本中，65份（14.0%）通过实时PCR检测为stx阳性，分离出7株STEC菌株。stx2基因在粪便样本（90.4%对8.4%）和NRTE猪肉产品（13.3%对1.3%）中的检测频率均高于stx1基因。分析中纳入的所有RTE样本均为阴性。在stx1和stx2基因检测呈阳性的样本中，血清群相关基因的检测频率较高：O26在粪便样本中最为常见（81.3%），O145在猪肉产品中最为常见（88.1%）。O157血清群在猪肉产品和粪便样本中的阳性率分别为83.3%和78.1%。尽管通过实时PCR频繁检测到表明可能存在属于六个血清群的STEC菌株的基因，但细菌学检测步骤并未确认分离出任何此类菌株。
