Kindle Patrick, Zurfluh Katrin, Nüesch-Inderbinen Magdalena, von Ah Sereina, Sidler Xaver, Stephan Roger, Kümmerlen Dolf
1Vetsuisse Faculty, Institute for Food Safety and Hygiene, University of Zurich, Winterthurerstrasse 272, CH-8057 Zurich, Switzerland.
2Department of Farm Animals, Division of Swine Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Porcine Health Manag. 2019 Feb 28;5:9. doi: 10.1186/s40813-019-0116-y. eCollection 2019.
In the last decade, the growth of the pig-farming industry has led to an increase in antibiotic use, including several used in human medicine, e.g. (fluoro)quinolones. Data from several studies suggest that there is a link between the agricultural use of antibiotics and the prevalence of antibiotic-resistant bacteria in the pig farm environment, including (fluoro)quinolone resistance. This poses a threat to human and animal health. Our goal was to phenotypically and genotypically characterize 174 showing non-susceptibility to quinolones isolated from environmental samples from pig farms. Antimicrobial susceptibility testing (AST) was performed using the disk diffusion method. PCR and sequence analysis were performed to identify chromosomal mutations in the quinolone resistance-determining regions (QRDR) of and the isolates were screened for the presence of the plasmid-mediated quinolone resistance (PMQR) genes , , , , , and .Strain relatedness was assessed by phylogenetic classification and multilocus sequence typing (MLST).
Of 174 isolates, 81% ( = 141) were resistant to nalidixic acid, and 19% ( = 33) were intermediately resistant. Overall, 68.4% ( = 119) were multidrug resistant. This study revealed a prevalence of 79.9% ( = 139) for QRDR mutations, and detected 21.8% ( = 38) isolates with at least one PMQR gene. The two most frequently detected PMQR genes were and (13.8% ( = 24) and 9.8% ( = 17, respectively). belonging to phylogenetic group A (48.3%/ = 84) and group B1 (33.3% / = 58) were the most frequent. ST10 ( = 20) and ST297 (n = 20) were the most common STs.
with non-susceptibility to quinolones are widespread among the environment of Swiss pig farms and are often associated with an MDR phenotype. In several cases these isolates possess at least one PMQR gene, which could spread by horizontal gene transfer. from pig farms have diverse STs, some of which are associated with human and animal disease.
在过去十年中，养猪业的发展导致抗生素使用增加，包括几种用于人类医学的抗生素，例如（氟）喹诺酮类。多项研究数据表明，抗生素在农业中的使用与养猪场环境中抗生素耐药菌的流行之间存在联系，包括（氟）喹诺酮耐药性。这对人类和动物健康构成威胁。我们的目标是对从养猪场环境样本中分离出的174株对喹诺酮不敏感的菌株进行表型和基因型特征分析。采用纸片扩散法进行药敏试验。进行聚合酶链反应（PCR）和序列分析以鉴定gyrA和parC喹诺酮耐药决定区（QRDR）中的染色体突变，并筛选分离株中质粒介导的喹诺酮耐药（PMQR）基因qnrA、qnrB、qnrC、qnrD、qnrS、aac(6’)-Ib-cr和oqxA的存在情况。通过系统发育分类和多位点序列分型（MLST）评估菌株的相关性。
1并对174株分离株进行分析，其中81%（n = 141）对萘啶酸耐药，19%（n = 33）为中介耐药。总体而言，68.4%（n = 119）为多重耐药。本研究显示gyrA和parC QRDR突变的发生率为79.9%（n = 139），并检测到21.8%（n = 38）的分离株至少含有一个PMQR基因。最常检测到的两个PMQR基因是qnrS和qnrB（分别为13.8%（n = 24）和9.8%（n = 17））。属于系统发育组A（48.3%/n = 84）和组B1（33.3%/n = 58）的菌株最为常见。ST10（n = 20）和ST297（n = 20）是最常见的ST型。
对喹诺酮不敏感的大肠杆菌在瑞士养猪场环境中广泛存在，且常与多重耐药表型相关。在一些情况下，这些分离株至少含有一个PMQR基因，可能通过水平基因转移传播。来自养猪场的大肠杆菌具有多种ST型，其中一些与人类和动物疾病有关。
