Liang Zeyi, Shen Jiahao, Liu Jing, Sun Xu, Yang Yayuan, Lv Yanan, Zheng Juanshan, Mou Xiaoqing, Li Hongsheng, Ding Xuezhi, Yang Feng
Key Laboratory of New Animal Drug Project of Gansu Province/Key Laboratory of Veterinary Pharmaceutics Discovery, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agricultural Science, Lanzhou, Gansu, 730050, People's Republic of China.
Infect Drug Resist. 2023 May 4;16:2727-2735. doi: 10.2147/IDR.S408632. eCollection 2023.
This study aimed to investigate the prevalence and genetic characterization of isolates from clinical bovine mastitis in Ningxia Hui Autonomous Region of China.
was identified by the polymerase-chain reaction of 16S rRNA gene and sequencing. Antimicrobial susceptibility was tested by the disk diffusion method. Genes of resistance and virulence were determined by the PCR.
Overall, were confirmed from 32 of 2897 (1.1%) mastitis milk samples. These isolates showed high resistance to cefazolin (30/32, 93.8%) and chloramphenicol (28/32, 87.5%). A 12.5% (4/32) of the isolates displayed multidrug resistance (MDR). The most prevalent resistant genes found in were (32/32, 100%) and (24/32, 75.0%; , 14/32, 43.8%; , 8/32, 25.0%; , 2/32, 6.3%) for extended-spectrum beta-lactamase, (28/32, 87.5%) and (16/32, 50.0%) for chloramphenicol resistance, (2/32, 6.3%) for carbapenemases, and (28/32, 87.5%), (26/32, 81.3%), (26/32, 81.3%) and (20/32, 62.5%) for efflux pumps. Moreover, all isolates carried virulence genes , and , and most of them contained (30/32, 93.8%), (26/32, 81.3%), (26/32, 81.3%), (26/32, 81.3%), (24/32, 75.0%) and (24/32, 75.0%).
To our knowledge, this is the first report of genetic determinants for antimicrobial resistance and virulence in isolated from bovine mastitis cases in China. These findings are useful for developing strategies for prevention and treatment of bovine mastitis caused by in China.
本研究旨在调查中国宁夏回族自治区临床型牛乳腺炎分离株的流行情况及基因特征。
通过16S rRNA基因的聚合酶链反应和测序进行鉴定。采用纸片扩散法检测抗菌药物敏感性。通过PCR检测耐药基因和毒力基因。
总体而言，从2897份乳腺炎乳样中的32份（1.1%）中确认有分离株。这些分离株对头孢唑林（30/32，93.8%）和氯霉素（28/32，87.5%）表现出高度耐药。12.5%（4/32）的分离株表现出多重耐药（MDR）。分离株中最常见的耐药基因是用于超广谱β-内酰胺酶的blaTEM（32/32，100%）和blaSHV（24/32，75.0%；blaCTX-M，14/32，43.8%；blaOXA，8/32，25.0%；blaIMP，2/32，6.3%），用于氯霉素耐药的cat（28/32，87.5%）和floR（16/32，50.0%），用于碳青霉烯酶的blaKPC（2/32，6.3%），以及用于外排泵的qacEΔ1（28/32，87.5%）、qacA/B（26/32，81.3%）、mexA（26/32，81.3%）和mexB（20/32，62.5%）。此外，所有分离株都携带毒力基因fimA、papC和afa/draBC，并且大多数含有clyA（30/32，93.8%）、hlyA（26/32，81.3%）、cnf1（26/32，81.3%）、sfa/foc（26/32，81.3%）、gelE（24/32，75.0%）和afa/draBC（24/32，75.0%）。
据我们所知，这是中国首次报道从牛乳腺炎病例中分离出的大肠杆菌抗菌耐药性和毒力的遗传决定因素。这些发现有助于制定中国由大肠杆菌引起的牛乳腺炎的预防和治疗策略。
