摘要
为探究养殖的多纹钱蝶鱼(Selenotoca multifasciata)病害频发的原因,建立有效的病害防控方法,对暴发于海南养殖场的多纹钱蝶鱼病害开展调查并进行灭活疫苗的研制及免疫保护效果评估。分离到2株病原菌LSSM和DFSM,经形态学和16S rDNA序列分析,将病原鉴定为海豚链球菌(Streptococcus iniae)。将这2株菌与实验室收集保藏的2株鱼源海豚链球菌(菌株GXTO和GXAS)进行了血清型鉴定和耐药性、致病性分析,制备了灭活疫苗并评价了疫苗的免疫保护效果。研究表明:4株海豚链球菌鉴定为血清Ⅰ型。所有菌株均对青霉素类、头孢类、四环素等23种抗生素高度敏感、对丁胺卡那耐药,其中海南株LSSM、DFSM对庆大霉素和卡那霉素抗生素耐药,广西株GXTO和GXAS对庆大霉素和卡那霉素敏感。DFSM、GXTO和LSSM对多纹钱蝶鱼的半数致死量(LD_(50))分别为7.20×10^(2)、2.72×10^(3)和3.40×10^(6) CFU/尾,GXAS未显示毒力。分别制备3株毒株(DFSM、GXTO和LSSM)的灭活疫苗,通过腹腔注射途径免疫多纹钱蝶鱼,各组免疫鱼在同源菌株攻毒后,获得的免疫保护率分别为84.6%~85.7%、69.2%~71.4%和33.3%~40.0%;此外,DFSM免疫鱼在异源毒株LSSM和GXTO攻毒后,获得的交叉免疫保护率分别为86.7%和100%。本研究确定了海豚链球菌是海南养殖的多纹钱蝶鱼病害频发的病原,使用DFSM株制备的海豚链球菌灭活疫苗对多纹钱蝶鱼有良好的免疫保护效果。
To clarify the reasons for the frequent disease,explode of cultured Selenotoca multifasciata,and develop effective disease control methods,epidemiological investigation of S.multifasciata disease in Hainan farms was carried out and inactivated vaccines were created and evaluated.Two pathogenic bacterial strains,named LSSM and DFSM,were isolated and identified as Streptococcus iniae through morphological and 16S rDNA sequence analyses.The serotype identification,drug resistance and pathogenicity analysis of the two isolated strains and the two fish-sourced,S.iniae GXTO and S.iniae GXAS,preserved in laboratory were carried out.Inactivated vaccines were prepared,and their immune protection effects were evaluated in S.multifasciata.The results showed that four strains belonged to serotype I.All strains were highly sensitive to 23 antibiotics including penicillin,cephalosporin and tetracycline among others,and resistant to tetracycline.The isolated strains,LSSM and DFSM,were resistant to gentamicin and kanamycin while two fish-sourced,GXTO and GXAS(from Guangxi),were sensitive to gentamicin and kanamycin.The median lethal dose(LD_(50))of DFSM,GXTO and LSSM to S.multifasciata was 7.20×10^(2),2.72×10^(3),and 3.40×10^(6) CFU/tail,respectively,but GXAS was not toxic.Inactivated vaccines were prepared,respectively,using the toxic strains,DFSM,GXTO and LSSM,and S.multifasciata were immunized via intraperitoneal injection.After challenged with original strains,DFSM,GXTO and LSSM,the immunized fish each group showed a relative percent survival rate(RPS)varying between 84.6%and 85.7%,69.2%and 71.4%,33.3%and 40.0%,respectively.In addition,DFSM-immunized fish obtained a cross-immunity protection rate of 86.7%and 100%after infected by the original LSSM and GXTO.Our findings confirmed that S.iniae is the pathogen frequently occurring in cultured S.multifasciata in Hainan,and the inactivated vaccine of S.iniae prepared using DFSM has a good immune protection effect.
作者
尚忠
唐磊
王连慧
黄海
茅云翔
莫照兰
Shang Zhong;Tang Lei;Wang Lianhui;Huang Hai;Mao Yunxiang;Mo Zhaolan(Key Laboratory of Tropical Aquatic Germplasm of Hainan Province,Sanya Oceanographic Institution,Ocean University of China,Sanya 572024,China;Key Laboratory of Marine Genetics and Breeding,Ministry of Education,College of Marine Life Sciences,Ocean University of China,Qingdao 266003,China;Key Laboratory of Utilization and Conservation of Tropical Marine Bioresource,Ministry of Education,College of Fisheries and Life Science,Hainan Tropical Ocean University,Sanya 572022,China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第4期38-50,共13页
Periodical of Ocean University of China
基金
海南省自然科学基金项目(322RC743)
三亚崖州湾科技城管理局2019年重大科技项目(SKJC-KJ-2019KY01)
国家重点研究发展计划项目(2022YFD2400505)资助。
关键词
多纹钱蝶鱼
海豚链球菌
灭活疫苗
分离鉴定
半数致死量
相对存活率
交叉免疫
Selenotoca multifasciata
Streptococcus iniae
inactivated vaccine
isolation and identification
median lethal dose
relative percent survival rate
cross-immunity protection
