Shiga toxin type 2e (Stx2e) Escherichia coli is the causative factor of diarrhea and edema in swine. The aims of this study were to determine the prevalence of Stx2e-producing E. coli isolates and to characterize isolates from clinical cases of pig colibacillosis and healthy swine. During the 11 years of the study (2006–2017), a total of 233 Stx2e-producing isolates were detected−230 out of 2,060 (11.16%) E. coli isolated from diseased pigs and 3 out of 171 (1.75%) from healthy swine. Stx2e-producing isolates were indeed more present in clinical colibacillosis cases than in healthy pigs (p = 0.0002). The predominant serogroup was O139 (79.82%) and the most common fimbrial factor present in these isolates was F18 (177 isolates), followed by F6 (5 isolates). The enterotoxins LTI, STa, and STb were detected in 10.43, 41.73, and 48.26% of the isolates, respectively. The predominant virotypes F18-Stx2e and -STa-STb-Stx2e were similarly present in weaners (33.33 and 35.52%) and finishers (38.30 and 25.53%). Among isolates from diseased pigs, O139 and F18 were the more frequently identified serogroup and virulence factor, respectively. Of the tested 230 Stx2e-producing isolates isolated from diseased pigs, 29 (12.60%) harbored genes encoding ESBL, particularly TEM (79.30%), CTX-M1 (17.20%), and CMY-2 (3.40%). Antimicrobial resistance to tetracycline was the most common characteristic (98.25%), followed by ampicillin (93.91%), cephalotin (90.43%) and trimethoprim/sulfamethoxazole (82.17%). Our results showed that Stx2e-producing E. coli were more frequently associated with clinical forms of colibacillosis, with minimal probability to isolate these isolates from healthy pigs.

志贺毒素2e型（Stx2e） 大肠杆菌是猪腹泻和水肿的病因。这项研究的目的是确定产生Stx2e的患病率大肠杆菌分离株，并从猪大肠杆菌病和健康猪的临床病例中鉴定分离株。在研究的11年（2006-2017）中，共检测到233株产生Stx2e的分离株-在2,060株中占230株（11.16％）大肠杆菌从患病猪中分离出来，从171头健康猪中分离出三只（1.75％）。实际上，在临床大肠埃希菌病病例中，产生Stx2e的分离株比在健康猪中更多（p= 0.0002）。血清群主要为O139（79.82％），这些分离株中最常见的纤维因子是F18（177个分离株），其次是F6（5个分离株）。分别在10.43、41.73和48.26％的分离物中检测到肠毒素LTI，STa和STb。断奶仔猪（33.33和35.52％）和育肥猪（38.30和25.53％）中也同样存在主要的病毒型F18-Stx2e和-STa-STb-Stx2e。在患病猪的分离株中，O139和F18分别是最常见的血清群和毒力因子。在从患病猪中分离出的230个产生Stx2e的分离株中，有29个（12.60％）带有编码ESBL的基因，特别是TEM（79.30％），CTX-M1（17.20％）和CMY-2（3.40％）。最常见的特征是对四环素的抗药性（98.25％），其次是氨苄西林（93.91％），头孢氨苄（90.43％）和甲氧苄啶/磺胺甲基异恶唑（82.17％）。我们的结果表明产生Stx2e大肠杆菌 大肠杆菌更常与大肠埃希菌病的临床形式相关，因此从健康猪中分离出这些分离株的可能性很小。