This study aims to evaluate the prevalence of multidrug-resistant (MDR) and biofilm-forming pathogens from animal source compared to clinical ones. In addition, to assess the antibacterial and antibiofilm activity of silver nanoparticles (AgNPs) alone and/or mixed with vancomycin. Out of 62 bacterial isolates from animal respiratory tract infection (RTI), 50.00% were defined as MDR, while among human ones, 44.00% were MDR. The bacteria Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pneumoniae were the predominant isolated bacteria from both animal and human origin with frequency percentage of 50.00, 22.32, and 18.75, respectively. Among Staph. aureus strains, mecA gene was detected in 60.00% and 61.54% of animal and human isolates, respectively, while mec_ALGA251 (mecC) gene was detected in 13.33% and 15.38% of animal and human isolates, respectively. Biofilm formation ability among animal isolates was 83.87%, while among human ones was 86.00%. AgNPs were effective in inhibiting planktonic cells with minimal inhibitory concentration (MIC) values (0.625–10 μg/mL), as well as eradicating biofilm with minimal biofilm eradication concentration values (1.25–10 μg/mL). Noticeable low MIC of AgNPs was required for the isolates from animal source (0.625–5 μg/mL) compared to clinical ones (0.625–10 μg/mL). Remarkable reduction in AgNP effective concentration was observed after combination with 1/4 MIC of vancomycin with minimum recorded concentration of 0.08 μg/mL. In conclusion, the prevalence of MDR among RT pathogens was recorded with high ability to produce biofilm and virulence factors from both animal and human pathogens. AgNPs showed strong antibacterial and antibiofilm activity alone and mixed with vancomycin, with up to fourfold reduction of AgNP inhibitory dose.

中文翻译：

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银纳米颗粒和万古霉素的组合克服来自临床和动物来源的浮游生物/生物膜细胞的抗生素耐药性。

本研究旨在评估与临床病原体相比，动物来源的多重耐药性 (MDR) 和生物膜形成病原体的流行情况。此外，评估单独和/或与万古霉素混合的银纳米粒子 (AgNPs) 的抗菌和抗生物膜活性。在来自动物呼吸道感染 (RTI) 的 62 株细菌分离物中，50.00% 被定义为 MDR，而在人类中，44.00% 被定义为 MDR。细菌金黄色葡萄球菌，铜绿假单胞菌，和肺炎链球菌是来自动物和用50.00，22.32，18.75和分别频率百分比人类来源的主要分离的细菌。在葡萄球菌之中。金黄色葡萄球菌，mecA分别在 60.00% 和 61.54% 的动物和人类分离株中检测到基因，而mec _ALGA251 (mecC)分别在 13.33% 和 15.38% 的动物和人类分离物中检测到基因。动物分离物的生物膜形成能力为83.87%，而人类分离物的生物膜形成能力为86.00%。AgNPs 以最小抑制浓度 (MIC) 值 (0.625–10 μg/mL) 有效抑制浮游细胞，并以最小生物膜根除浓度值 (1.25–10 μg/mL) 根除生物膜。与临床分离物 (0.625-10 μg/mL) 相比，动物源分离物 (0.625-5 μg/mL) 需要显着低的 AgNPs MIC。与 1/4 MIC 的万​​古霉素组合后观察到 AgNP 有效浓度显着降低，最低记录浓度为 0.08 μg/mL。总之，RT 病原体中 MDR 的流行被记录为具有从动物和人类病原体产生生物膜和毒力因子的高能力。AgNPs 单独和与万古霉素混合显示出强大的抗菌和抗生物膜活性，AgNP 抑制剂量降低了四倍。