大黄鱼中哈维氏弧菌毒力及耐药特性分析

Virulence and antimicrobial resistance of Vibrio harveyi in large yellow croaker

中文关键词:  哈维氏弧菌  耐药特征  耐药基因  毒力基因

英文关键词:Vibrio harveyi  antimicrobial resistance  resistance gene  virulence gene

中文摘要:

      目的 分析鉴定海产养殖中主要病原哈维氏弧菌的毒力及耐药特性。方法 采集来自于网箱养殖区病死大黄鱼, 分离并鉴定哈维氏弧菌, 利用微量肉汤稀释法分析分离株对13种抗生素的敏感特性, PCR鉴定耐药基因(tetA、tetB、ermA、ermB、ermC、mecA、aac(6’)-Ib、oqxA、sul1、sul2、mcr-1)及其毒力基因。结果 从病料中分离并鉴定出54株哈维氏弧菌, 耐药分析表明对硫酸粘杆菌素、庆大霉素、四环素、氨苄西林、复方新诺明和阿莫西林均耐药, 96.2%的分离株对头孢噻呋, 92.6%的分离株对链霉素、阿米卡星表现为耐药, 88.9%的分离株对恩诺沙星, 87.1%的分离株对卡那霉素呈现高度耐受特性。所有分离株同时对9种抗生素显示100%耐药, 同时耐受10种抗生素的菌株有94.4%, 同时对11和12种抗生素耐受的菌株分别达到85.2%和64.8%, 对13种抗生素均产生耐药的菌株达到37.0%(20/54)。耐药基因分析表明四环素类tetA为主要耐药基因, 检出率高达81.5%; 氨基糖苷类aac(6’)-Ib, β-内酰胺类mecA, 磺胺类sul1、sul2, 喹诺酮类oqxA和大环内酯类ermA、ermC分别检出4~7株。毒力基因分析表明toxR携带率高达75.9%。结论 本研究分析了海产养殖中主要病原哈维氏弧菌感染状况, 其耐药严重且普遍携带毒力基因, 表明哈维氏弧菌耐药和毒力对海产养殖造成重要威胁。同时本研究为弧菌病的有效防治提供参考依据。

英文摘要:

      Objective To analyze and identify of virulence and drug resistance of Vibrio harveyi, which is the main pathogen in marine culture. Methods Vibrio harveyi was isolated and identified from dead yellow croaker collected from cage culture area. Antibiotic susceptibility was tested by broth microdilution with 13 antibiotics. Resistance genes (tetA, tetB, ermA, ermB, ermC, mecA, aac(6’)-Ib, oqxA, sul1, sul2 and mcr-1)and virulence genes were identified by PCR. Results Totally 54 Vibrio harveyi strains were identified from the infected materials. Resistance analysis showed that all strains were resistant to colistin sulfate, gentamicin, tetracycline, ampicillin, co-trimoxazole and amoxicillin, 96.2% of the isolates showed resistance to cefotaxime, 92.6% of the isolates showed resistance streptomycin and amikacin, and 88.9% and 87.1% of the isolates showed high resistance to enrofloxacin and kanamycin. All isolates showed 100% resistance to 9 antibiotics at the same time, 94.4% of the strains were resistant to 10 antibiotics at the same time, 85.2% and 64.8% of the strains were resistant to 11 and 12 antibiotics, respectively, and 37.0% of the strains were resistant to 13 antibiotics (20/54). From the results of resistance genes, tetA was the main resistance gene, and the detection rate was as high as 81.5%. Aminoglycosides aac(6')-Ib, β-lactam mecA, sulfonamide sul1, sul2, quinolones oqxA and macrolides ermA, ermC were detected in 4-7 strains, respectively. The results of the virulence genes test showed that the frequency of toxR carrying rate was as high as 75.9%. Conclusion This study analyzed the infection status of Vibrio harveti, the main pathogens in marine aquaculture, and its drug resistance was severe and it generally carried virulence genes, indicating that the drug resistance and virulence of Vibrio harveti posed an important threat to marine aquaculture. At the same time, this study provides a reference for the effective prevention and treatment of Vibriosis.