We aimed to determine the antimicrobial susceptibility profile of pathogenic strains isolated from fecal samples of calves and buffalo calves (2008–2013), in Minas Gerais, Brazil, as well as the frequency of O157 gene and strains carrying extended-spectrum beta-lactamases (ESBL) and mobile colistin resistance () genes. strains (n=518) were tested for susceptibility against ten antimicrobials. Tetracycline was the antimicrobial with the highest resistance rate (382/518), followed by ampicillin (321/518), sulfamethoxazole/trimethoprim (312/518), chloramphenicol (192/518), gentamicin (126/518), ciprofloxacin (148/518), cefazolin (89/518), colistin (54/518) and cefoxitin (34/518). Multidrug resistance (MDR) was observed in 381/518 isolates. No strain harbored or O157 genes whereas 19/99 were ESBL positive. The most prevalent pathotype and phylogroup were STEC and B1, respectively. Age, EHEC pathotype and resistance to aminoglycoside and cephem were significantly associated with MDR in the multivariate model. Overall, strains showed high rates of resistance to penicillin, tetracyclines and folate inhibitors, in addition to an alarming rate of MDR and ESBL-producing strains.

中文翻译：

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与从小牛身上分离出的致病性大肠杆菌相关的抗菌素耐药性以及公共和动物健康风险

我们的目的是确定从巴西米纳斯吉拉斯州小牛和水牛犊粪便样本（2008-2013）中分离出的致病菌株的抗菌敏感性概况，以及 O157 基因和携带广谱 β-内酰胺酶的菌株的频率（ ESBL) 和移动粘菌素抗性 () 基因。测试了菌株 (n=518) 对 10 种抗菌药物的敏感性。耐药率最高的抗菌药物是四环素（382/518），其次是氨苄西林（321/518）、磺胺甲恶唑/甲氧苄啶（312/518）、氯霉素（192/518）、庆大霉素（126/518）、环丙沙星（148）。 /518)、头孢唑林 (89/518)、粘菌素 (54/518) 和头孢西丁 (34/518)。在 381/518 株分离株中观察到多重耐药性 (MDR)。没有菌株携带 O157 基因，而 19/99 菌株呈 ESBL 阳性。最常见的致病型和系统群分别是 STEC 和 B1。在多变量模型中，年龄、肠出血性大肠杆菌病型以及对氨基糖苷类和头孢烯类药物的耐药性与 MDR 显着相关。总体而言，菌株对青霉素、四环素和叶酸抑制剂表现出较高的耐药率，此外，产生 MDR 和 ESBL 的菌株的耐药率也令人震惊。