Chen Wenyan, Xu Ziheng, Li Changcheng, Wang Can, Wang Min, Liang Jingzhen, Wei Ping
Institute for Poultry Science and Health, Guangxi University, Nanning, China.
School of Public Health and Management, Guangxi University of Chinese Medicine, Nanning, China.
Front Vet Sci. 2023 Aug 31;10:1248584. doi: 10.3389/fvets.2023.1248584. eCollection 2023.
The study explored the biofilm (BF) formation capacity, BF-related gene profiles, and the trends in antimicrobial resistance (AMR) of (SP) strains over several years. A total of 627 SP strains were isolated from 4,540 samples collected from chicken farms in Guangxi, China during 2018-2022. The BF-forming capacity of these isolates was assessed using crystal violet staining, and the presence of eight BF-related genes (, and ) in BF formation-positive strains was determined through Polymerase Chain Reaction (PCR) analysis. Antimicrobial susceptibility test was conducted to investigate the AMR of the isolates. Minimum Inhibitory Concentration (MIC) and Minimal Biofilm Eradication Concentration (MBEC) of nine SP-BF strains were determined using the broth microdilution method to assess the impact of BF formation on AMR. Additionally, the Optimal Biofilm Formation Conditions (OBFC) were investigated. The results indicated that 36.8% (231/627) of the strains exhibited a positive BF-formation capacity. Among these, 24.7% (57/231) were strong BF producers, 23.4% (54/231) were moderate BF producers, and 51.9% (120/231) were weak BF producers. Analysis of the eight BF-related genes in SP-BF strains revealed that over 90% of them were positive for all the genes. Antimicrobial susceptibility test conducted on the isolates showed that 100% (231/231) of them exhibited resistance to at least one antibiotic, with 98.3% (227/231) demonstrating multidrug resistance (MDR). Both MIC and MBEC measurements indicated varying degrees of increased AMR after BF formation of the bacteria. The optimal conditions for BF formation were observed at 37°C after 48 h of incubation, with an initial bacterial concentration of 1.2 × 10 CFU/mL. Notably, NaCl had a significant inhibitory effect on BF formation, while glucose and Trypticase Soy Broth (TSB) positively influenced BF formation. The results of the study emphasized the need for effective preventive and control strategies to address the challenges posed by the BF formation and MDR of SP in the field.
该研究探讨了多年来鸡源致病性沙门氏菌（SP）菌株的生物膜（BF）形成能力、BF相关基因谱以及抗菌药物耐药性（AMR）趋势。2018年至2022年期间，从中国广西养鸡场采集的4540份样本中分离出627株SP菌株。使用结晶紫染色评估这些分离株的BF形成能力，并通过聚合酶链反应（PCR）分析确定BF形成阳性菌株中8个BF相关基因（、和）的存在情况。进行抗菌药物敏感性试验以研究分离株的AMR。使用肉汤微量稀释法测定9株SP-BF菌株的最低抑菌浓度（MIC）和最低生物膜清除浓度（MBEC），以评估BF形成对AMR的影响。此外，还研究了最佳生物膜形成条件（OBFC）。结果表明，36.8%（231/627）的菌株表现出阳性BF形成能力。其中，24.7%（57/231）为强BF生产者，23.4%（54/231）为中度BF生产者，51.9%（120/231）为弱BF生产者。对SP-BF菌株中8个BF相关基因的分析表明，超过90%的菌株所有基因均为阳性。对分离株进行的抗菌药物敏感性试验表明，100%（231/231）的菌株对至少一种抗生素耐药，98.3%（227/231）表现出多重耐药（MDR）。MIC和MBEC测量均表明，细菌形成BF后AMR有不同程度的增加。观察到BF形成的最佳条件是在37°C孵育48小时后，初始细菌浓度为1.2×10 CFU/mL。值得注意的是，NaCl对BF形成有显著抑制作用，而葡萄糖和胰蛋白胨大豆肉汤（TSB）对BF形成有积极影响。该研究结果强调需要有效的预防和控制策略，以应对现场SP的BF形成和MDR带来的挑战。
