Department of Pathobiology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad 9177948974, Iran.
Department of Pathobiology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad 9177948974, Iran.
Comp Immunol Microbiol Infect Dis. 2024 Sep;112:102226. doi: 10.1016/j.cimid.2024.102226. Epub 2024 Aug 8.
This study investigates the presence of virulence-associated genes and antimicrobial resistance (AMR) in Escherichia fergusonii isolates obtained from ostrich chicks. A total of 287 isolates were recovered from 106 fecal samples from ostrich chicks suffering from diarrhea and subjected to molecular identification and biochemical characterization. E. fergusonii was detected in 10 samples (9.4 %) using two PCR-detection protocols. Notably, the isolates lacked various virulence genes commonly associated with pathogenic E. coli including elt, est, stx, eae, ehly, cdt, iss, iutA, iroN, hlyA, ompT, except for one isolate harboring the astA gene. Antimicrobial susceptibility testing revealed that all isolates were susceptible to ciprofloxacin, while high resistance was observed against amoxicillin clavulanate (AMC), trimethoprim-sulfamethoxazole (SXT), and doxycycline (D). Moreover, eight isolates displayed multidrug resistance (MDR) and four exhibited resistance to 9-11 antimicrobials. The most frequent resistance gene was sul2, which was present in all isolates; the other resistance genes detected consisted of int1 (4/10), int2 (3/10), bla (2/10), and qnrS, bla, bla, bla, and flo each were detected only in one E. fergusonii Isolate. Plasmid replicon typing identified the presence of I1 (7/10), N (5/10), and Y (1/10). This study provides valuable insights into the virulence and antimicrobial resistance of E. fergusonii isolates from ostrich chicks, highlighting the complexity of antimicrobial resistance mechanisms exhibited by these bacteria. Further research is essential to understand the transmission dynamics and clinical implications of these findings in veterinary and public health settings.
本研究调查了从患有腹泻的鸵鸟雏鸡粪便样本中获得的弗格森埃希氏菌分离株中毒力相关基因和抗生素耐药性（AMR）的存在情况。从 106 份鸵鸟雏鸡粪便样本中回收了 287 株分离株，并进行了分子鉴定和生化特征分析。使用两种 PCR 检测方案在 10 个样本（9.4%）中检测到 E. fergusonii。值得注意的是，除了一个携带 astA 基因的分离株外，这些分离株缺乏与致病性大肠杆菌相关的各种毒力基因，包括 elt、est、stx、eae、ehly、cdt、iss、iutA、iroN、hlyA、ompT。抗生素药敏试验结果显示，所有分离株均对环丙沙星敏感，而对阿莫西林克拉维酸（AMC）、复方磺胺甲噁唑（SXT）和强力霉素（D）高度耐药。此外，有 8 株分离株表现出多重耐药（MDR），4 株分离株对 9-11 种抗生素表现出耐药性。最常见的耐药基因是 sul2，存在于所有分离株中；其他检测到的耐药基因包括 int1（4/10）、int2（3/10）、bla（2/10）和 qnrS、bla、bla、bla，flo 各仅在 1 株 E. fergusonii 分离株中检出。质粒复制子分型鉴定出 I1（7/10）、N（5/10）和 Y（1/10）的存在。本研究为鸵鸟雏鸡弗格森埃希氏菌分离株的毒力和抗生素耐药性提供了有价值的见解，突出了这些细菌表现出的抗生素耐药机制的复杂性。进一步的研究对于了解这些发现在兽医和公共卫生领域的传播动态和临床意义至关重要。
