摘要
      沙门氏菌是一种重要的肠道病原体，对人类和牲畜的健康构成威胁，新出现的多药耐药性（MDR）是全球的一个主要公共卫生问题。我们调查了泰国养猪场健康猪和患病猪中沙门氏菌的流行情况，并确定了它们的表型和基因型抗微生物耐药性谱。从泰国南部四个不同的养猪场的围栏里饲养的猪身上总共采集了150份粪便样本，并对其进行了沙门氏菌检测。对已确认的沙门氏菌分离株进行了对11种抗菌药物的易感性测试，并使用聚合酶链式反应检测已知的抗菌耐药性基因（ARGs）。从69%（103/150）的粪便样本中培养出沙门氏菌分离株，与健康猪（91/135；67%）相比，患病猪的患病率更高（12/15；80%）。血清型里森是沙门氏菌分离株中最常见的血清型。对氨苄青霉素（AMP）（97%）、磺酰胺甲氧苄啶（SXT）（98%）和四环素（TET）（94%）的耐药性是观察到的最常见的表型。鉴定出的最常见的ARGs是blaTEM基因（99.%）、tetA基因（87%）、sul1基因（77%）和dfrA1基因（74%），并且95%以上的沙门氏菌分离株是基于对三种或多种抗菌药物的耐药性的耐多药菌株。表现出的最常见的抗微生物耐药性模式是AMP-TET-SXT（76%），在健康猪和患病猪中都观察到对粘菌素的耐药性（通过mcr-1基因）。血清型鼠伤寒的PFGE克隆群分析揭示了从不同养猪场的健康猪和患病猪中分离出的沙门氏菌之间的遗传关系。
Abstract
Salmonella is an important enteric pathogen that poses a threat to human and livestock animal health, with emerging multidrug resistance (MDR) a major public health issue globally. We investigated the prevalence of Salmonella in healthy and diseased pigs from Thai pig farms and determined their phenotypic and genotypic antimicrobial resistance profiles. A total of 150 fecal samples were collected from pigs housed in pens from four separate pig farms in southern Thailand and tested for the presence of Salmonella. Confirmed Salmonella isolates were tested for their susceptibility to 11 antimicrobials, and PCR used to detect known antimicrobial resistance genes (ARGs). Salmonella isolates were cultured from 69% (103/150) of all fecal samples, with higher prevalence in disease pigs (12/15; 80%), compared with healthy pigs (91/135; 67%). Serotype Rissen was the most frequently identified serotype among the Salmonella isolates. Resistance to ampicillin (AMP) (97%), sulfonamide-trimethoprim (SXT) (97%), and tetracycline (TET) (94%) were the most common phenotypes observed. The most common ARGs identified were blaTEM gene (99.%), tetA (87%), sul1 (77%), and dfrA1 (74%), and more than 95% of the Salmonella isolates tested were MDR - based on resistance to three or more antimicrobial classes. The most common antimicrobial resistance pattern exhibited was AMP-TET-SXT (76%), and resistance to colistin (via the mcr-1 gene) was observed in both healthy and diseased pigs. The clonal groups of PFGE analysis in serotype Typhimurium revealed the genetic relationship among Salmonella isolated from healthy and diseased pigs from different pig farms.

https://www.biorxiv.org/content/10.1101/2023.01.31.526471v1.abstract