摘要: |
2012年6~9月福建省沿海城市凡纳滨对虾养殖高位池发生病害,主要症状表现为肝胰腺发白肿大,空肠,死亡率50%以上.本研究对发病现场患病对虾的肝胰腺进行了微生物分离鉴定,BOX-PCR鉴定所分离的菌株为一株优势细菌,编号为1937.通过16S rRNA基因分析确定该菌株为弧菌属(Vibnio sp.).进一步基于rpoD、topA和toxR 3个基因的多位点序列分析(MISA),表明该菌株为副溶血弧菌(Vibro parahaemolyticus).从该菌株中还扩增获得副溶血弧菌特异性的溶血素基因.人工浸浴感染试验表明,菌株1937对凡纳滨对虾后期幼体表现出较强致病性,半致死浓度为1.33×10⁶cfu/cm³.肌肉注射感染试验表明该菌株对凡纳滨对虾成虾也具有致病性,半致死浓度为1.42×10⁶cfu/cm³,并且注射后成虾肌肉白浊,肝胰腺发白,致死率高于其他已报道的致病性弧菌,该菌株极有可能为此次发病的主要病原菌.抗生素试验表明,该菌株对诺氟沙星等29种抗生素中的20种比较敏感.这些研究结果对于该病原菌导致的虾病暴发的防控有参考价值. |
关键词: 海洋生物学 凡纳滨对虾 副溶血弧菌 病原菌 多位点序列分析(MLSA) |
DOI: |
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基金项目:国家海洋局公益性行业科研专项资助项目(2010005032) |
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Isolation and identification of a bacterial pathogen,Vibrioparahaemolyticus,for vibriosis of Litopenaeus vannamei |
LI Xiaoyi,WANG Liping,HUANG Hui,CHEN Yanwu,SHAO Zongze |
(Key Laboratory of Marine Genetic Resoures,Third Institute of Oceamography,SOA,Key Laboatory of Marine GeneticResources of Fujian Pnovince,Collaborative Ihnovation Center of Deep Sea Biology,Xiamen 361005,China;School of MarineScience,Ningbo University,Ningbo 315000,China;School of Life Sciences,Xiamen University,Xiamen 361005,China) |
Abstract: |
Mass mortality of shrimp Litopenaeus vanmamei occurred in shrimp fams in a coastal city,Zhangpu Coun-ty,Fujian Province,from June to September,2012.The disease outbreak caused heavily economicloss to shrimpculture industry.The symptom of infected shrimps showed a swelled and whitened hepatopancreas and empty intes-tine,with mortality over 50%.Bacteria were isolated from the hepatopancreas of infected shrimps,with a dominantone designated as strain 1937.Based on 16S RNA and multilocus sequence analysis(poD,toxR and poA gene),strain 1937 was identified as Vibrio parahaemolyticus.What's more,the haemolysin gene(zlh)specific to V.para-haemolyticus was also detected in strain 1937.Pathogenicity test byimmersion infection confimed that strain 1937was viulent to Litopenaeus vannamei post larvae and adults,and the LC,value was 1.33×10⁶cfu/cm³and1.42×10⁶cfu/cm³,respectively.The symptom of the shrimps challenged with bacterial strain1937 demonstratedthe same as the ones in shrimp fams.Thus,V.parahaemolyticus strain 1937 was proposed as the causative agentfor this disease outbreak of shrimp Litopenaeus tamamei. |
Key words: marine biology Litopenaeus vannamei Vibnio parahaemolyticus pathogenic bacteria multilocus se-quence analysis(MLSA) |