Introduction. The emergence and spread of non-typhoidal Salmonella enterica (NTS) serovars resistant to fluoroquinolones and third- and higher-generation cephalosporins is a matter of great concern. Antimicrobial-resistant NTS is increasingly being discovered in humans, animals, food animals, food products, and agricultural environments. Pigs are considered a major reservoir of antimicrobial-resistant Salmonella spp. Hypothesis/Gap Statement. Fluoroquinolone-resistant Salmonella spp. warrant further surveillance and characterization for a better understanding of the bacteria isolated from animals. Aim. NTS isolated from pork from slaughterhouses across Thailand were characterized in terms of their serovars; resistance to fluoroquinolones, third-generation cephalosporins, and carbapenems; and antimicrobial resistance genes. Methodology. A total of 387 NTS isolates, collected from slaughtered pigs in ten provinces across Thailand between 2014 and 2015, were characterized based on their serovars, antimicrobial resistance genes, and susceptibility to fluoroquinolones, third-generation cephalosporins, and carbapenems. Results. Among all NTS isolates, S. enterica serovar Rissen was predominant. Antimicrobial resistance was exhibited in 93/387 isolates (24 %). Although 24 (6.2 %) isolates were susceptible to all the tested antimicrobials, they were found to possess β-lactamase genes, such as bla TEM, bla SHV, or bla CTX-M. Mobilized colistin-resistant genes (mcr) and resistance to colistin were not observed in any tested isolate. Carbapenem resistance was detected in ten isolates (10.7 %); however, bla KPC, bla NDM, bla OXA-48-like, and bla IMP were not present. Among the 93 antimicrobial-resistant isolates, 87.1 % showed fluoroquinolone resistance with the quinolone resistance gene (qnrS) combined with topoisomerase genes parC (T57S) or gyrA (S83E/Y and D124E/G) substitutions, or topoisomerase gene substitutions alone. Conclusion. We found high fluoroquinolone resistance rates among the NTS isolates from pigs from slaughterhouses. The fluoroquinolone resistance mechanism in NTS was associated with the combination of qnrS and substitutions in gyrA, parC, or both. To prevent the transmission of antimicrobial-resistant NTS between animals and humans, continuous monitoring, surveillance, and regulation of Salmonella in the pork supply chain are pivotal.

中文翻译：

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泰国屠宰猪分离的非伤寒沙门氏菌对氟喹诺酮类药物的耐药性

介绍。对氟喹诺酮类和第三代及更高代头孢菌素耐药的非伤寒沙门氏菌(NTS) 血清型的出现和传播引起了极大关注。在人类、动物、食用动物、食品和农业环境中越来越多地发现抗微生物 NTS。猪被认为是耐药性沙门氏菌的主要宿主。假设/差距陈述。耐氟喹诺酮类沙门氏菌。为了更好地了解从动物身上分离出来的细菌，需要进一步监测和表征。目的。 从泰国各地屠宰场的猪肉中分离出的 NTS 的特征在于其血清型；对氟喹诺酮类、第三代头孢菌素和碳青霉烯类耐药；和抗微生物基因。方法。2014 年至 2015 年期间，从泰国十个省的屠宰猪中收集了 387 株 NTS 分离株，根据其血清型、抗菌素耐药基因以及对氟喹诺酮类、第三代头孢菌素和碳青霉烯类药物的敏感性进行了表征。结果。在所有 NTS 分离株中，S. enterica 血清型 Rissen 占优势。93/387 个分离株 (24%) 表现出抗微生物药物耐药性。尽管 24 个 (6.2%) 分离株对所有测试的抗菌剂均敏感，但发现它们具有 β-内酰胺酶基因，例如bla TEM、bla SHV或bla CTX-M。在任何测试分离株中均未观察到动员的粘菌素抗性基因 ( mcr ) 和对粘菌素的抗性。在 10 个分离株中检测到碳青霉烯类耐药性（10.7%）；然而，bla KPC、bla NDM、bla OXA-48-like和bla IMP不在场。在 93 株耐药菌株中，87.1% 的喹诺酮耐药基因 ( qnrS ) 与拓扑异构酶基因parC (T57S) 或gyrA（S83E/Y 和 D124E/G）替代或单独的拓扑异构酶基因替代显示出氟喹诺酮耐药性。结论。我们发现来自屠宰场猪的 NTS 分离株的氟喹诺酮耐药率很高。NTS 中的氟喹诺酮耐药机制与qnrS和gyrA、parC、或两者。为了防止抗微生物 NTS 在动物和人类之间传播，对猪肉供应链中的沙门氏菌进行持续监测、监视和监管至关重要。