Laboratório de diagnóstico de Doenças infectocontagiosas, Universidade do Oeste de Santa Catarina, Xanxerê, 89820-000, Santa Catarina, Brasil.
DB Serviços Veterinários LTDA, Abelardo Luz, Santa Catarina, 89830-000, Brasil.
Braz J Microbiol. 2024 Jun;55(2):2013-2024. doi: 10.1007/s42770-024-01320-2. Epub 2024 Apr 19.
In this study, the main agents associated with endometritis in cows in the state of Santa Catarina, Brazil, were identified and the resistance profile and virulence mechanisms of the bacterial isolates were evaluated. Isolates of Escherichia coli and Trueperella pyogenes were tested for their biofilm forming ability and the antimicrobial action of bromhexine hydrochloride in combination with other antimicrobials. A total of 37 uterine lavage samples were collected from cows with endometritis. Of the 55 bacteria isolated, 25.4% were identified as T. pyogenes and 16.3% as E. coli. The bacterial isolates showed greater resistance to sulfamethoxazole + trimethoprim (58.2%) and tetracycline (56.3%). Among the species, E. coli showed the highest resistance rates, with 100% of isolates showing resistance to amoxicillin, streptomycin, and gentamicin. The results of the minimum inhibitory concentration for the T. pyogenes isolates showed that 91.6% of the isolates were resistant to enrofloxacin and tetracycline, and 75% were resistant to ceftiofur and sulfamethoxazole + trimethoprim. All E. coli and T. pyogenes isolates showed biofilm forming ability. The plo, fimA, and nanH genes were identified in 100% of T. pyogenes isolates. In parallel, 100% of E. coli isolates had the fimH gene, and 11.1% had the csgD gene. Bromhexine hydrochloride showed antimicrobial activity against 100% of E. coli isolates and 66.6% of T. pyogenes isolates. Furthermore, when associated with antimicrobials, bromhexine hydrochloride has a synergistic and additive effect, proving to be an option in the treatment of endometritis in cows and an alternative for reducing the use of antimicrobials.
本研究旨在鉴定巴西圣卡塔琳娜州奶牛子宫内膜炎的主要病原体，并评估细菌分离株的耐药谱和毒力机制。我们测试了大肠杆菌和坏死梭杆菌的生物膜形成能力，以及盐酸溴己新与其他抗菌药物联合使用的抗菌作用。共采集了 37 份患有子宫内膜炎奶牛的子宫冲洗样本。从分离的 55 株细菌中，25.4%鉴定为坏死梭杆菌，16.3%鉴定为大肠杆菌。细菌分离株对磺胺甲噁唑+甲氧苄啶（58.2%）和四环素（56.3%）的耐药性更强。在这些种属中，大肠杆菌的耐药率最高，100%的分离株对阿莫西林、链霉素和庆大霉素耐药。坏死梭杆菌分离株的最低抑菌浓度结果表明，91.6%的分离株对恩诺沙星和四环素耐药，75%的分离株对头孢噻呋和磺胺甲噁唑+甲氧苄啶耐药。所有大肠杆菌和坏死梭杆菌分离株均具有生物膜形成能力。在 100%的坏死梭杆菌分离株中鉴定出了 plo、fimA 和 nanH 基因。同时，100%的大肠杆菌分离株具有 fimH 基因，11.1%的分离株具有 csgD 基因。盐酸溴己新对 100%的大肠杆菌分离株和 66.6%的坏死梭杆菌分离株均具有抗菌活性。此外，当与抗菌药物联合使用时，盐酸溴己新具有协同和累加作用，为治疗奶牛子宫内膜炎提供了一种选择，并可能减少抗菌药物的使用。
