| 摘要: |
| 为了向水产养殖中的科学用药提供更新、更充分的科学数据，本研究分析了凡纳滨对虾虾苗养殖池水中常见弧菌及其毒力基因和抗药性。该研究采用稀释涂布平板法和平板划线法对虾苗厂场育苗池水中的弧菌进行分离纯化，用革兰氏染色法、生化鉴定试剂盒进行进一步的种类鉴定，通过PCR扩增弧菌gyrB基因进行分子生物学鉴定，通过PCR扩增tdh、trh、pir-AVP、pir-BVP、toxR基因进行毒力基因分析，同时使用K-B纸片扩散法（Kirby-Bauer method）对菌株进行14种抗生素的药敏性试验。试验结果表明，：从虾苗厂场育苗池水中分离出溶藻弧菌2株，分别命名为菌株20221225G1、20221225Y2；副溶血弧菌1株，命名为菌株20221225G2；霍乱弧菌1株，命名为菌株20221225G3，。毒力基因分析揭示了菌株20221225G3与20221225Y2含有霍乱弧菌毒力表达调控基因（toxR）；。耐药性试验结果表明，氨苄西林、头孢噻吩、阿莫西林、阿米卡星对4株弧菌均无抑菌作用，而亚胺培南对4株弧菌有显著抑制效果。此外，携带毒力基因toxR的两株菌株对头孢噻肟表现出耐药性，而其他两株对头孢噻肟并没表现出耐药性。综上，本研究分离出的4株弧菌均显示出多重耐药性，携带毒力基因toxR的菌株显示出更强的耐药性。 |
| 关键词: 凡纳滨对虾 育苗池水 弧菌 分离鉴定 毒力基因 耐药性 |
| DOI： |
| 投稿时间：2025-04-17修订日期：2025-06-14 |
| 基金项目:广东省基础与应用基础研究基金[2021A1515010453],国家自然科学[31600322] |
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| Isolation and characterization of Vibrio from the original nursery pool water of Litopenaeus vannamei nursery ponds and analysis of drug resistance |
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CHEN Houhua1,2, QIU Xiaotong1,2, LIAO Guowei1,2, WU Qiuping1,2, FAN Lanfen1,2
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| (1.University Joint Laboratory of Guangdong Province,Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation,College of Marine Sciences,South China Agricultural University,Guangzhou,510642;2.China) |
| Abstract: |
| In order to provide a new and more adequate scientific data for scientific drug using in aquaculture, the virulence genes and antibiotic resistance of the Vibrio from the water of Litopenaeus vannamei nursery ponds were analyzed. This experiment employed dilution spread plate and streak plate methods for the isolation and purification of Vibrio from the the original nursery pool water. Further identification was carried out using Gram staining, biochemical identification kits, molecular biology techniques such as PCR amplification of gyrB genes for Vibrio identification, and PCR amplification of virulence genes such as tdh, trh, pir-AVP, pir-BVP, and toxR. The Kirby-Bauer method was also utilized for antibiotic susceptibility testing on 14 antibiotics. The results revealed 2 strains of Vibrio alginolyticus （strains 20221225G1 and 20221225Y2）, 1 strain of Vibrio parahaemolyticus（strain 20221225G2）, and 1 strain of Vibrio cholerae（strain 20221225G3）were isolated from the pool water. Virulence gene analysis indicated the presence of the cholera toxin regulatory gene（toxR）was presented in strains 20221225G3 and 20221225Y2. The results of antibiotic resistance test demonstrated that Ampicillin, Cephalothin, Amoxicillin and Amikacin had no inhibitory effect on 4 strains of Vibrio, while Imipenem had significant inhibitory effect on 4 strains of Vibrio. In addition, the strain carrying the virulence gene toxR showed resistance to cefotaxime, whereas the other two strains did not show resistance to cefotaxime. In summary, all the 4 strains of Vibrio were isolated in this study showed multi-drug resistance, and the strain carrying toxR showed stronger drug resistance. |
| Key words: Litopenaeus vannamei Nursery ponds Vibrio Isolation Virulence gene Drug tolerance |
