镜鲤野鲤碘泡虫病的诊断与组织病理损伤研究  

Diagnosis and Histopathological Damage of Myxobolus koi of Mirror Carp(Cyprinus carpio L.)

作　　者：樊威 贺扬 卓婷 罗煜 焦晓磊 王均 黄小丽[4] 苏建 FAN Wei;HE Yang;ZHUO Ting;LUO Yu;JIAO Xiaolei;WANG Jun;HUANG Xiaoli;SU Jian(Neijiang Academy of Agricultural Sciences,Neijiang 641000,China;College of Veterinary Medicine,Sichuan Agricultural University,Chengdu 611130,China;Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River,College of Life Sciences of Neijiang Normal University,Neijiang 641000,China;College of Animal Science&Technology,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川省内江市农业科学院,四川内江641000 [2]四川农业大学动物医学院,四川成都611130 [3]内江师范学院生命科学学院,长江上游鱼类资源保护与利用四川省重点实验室,四川内江641000 [4]四川农业大学动物科技学院,四川成都611130

出　　处：《云南农业大学学报（自然科学版）》2023年第2期234-240,共7页Journal of Yunnan Agricultural University:Natural Science

基　　金：四川省科技计划重点研发项目(2021YFS0359);四川省农科院科技成果中试熟化与示范转化工程子项目(2021ZSSFKJ07);内江市科技计划项目(2020KJJH005);大学生创新创业训练计划项目(X2021066)。

摘　　要：【目的】明确引起四川省某养殖场镜鲤(Cyprinus carpio L.)鳃出现乳白色赘生物的病原,探讨其对鳃组织的病理损伤,为该病的诊断和防治提供科学依据。【方法】采集发病症状明显的鱼,对其进行剖检、病原学检测(细菌、真菌、寄生虫)和分子生物学鉴定;采集鳃组织,通过病理学观察分析其致病性。【结果】病鱼脾和肾组织均未分离到细菌;鳃丝压片可见真菌菌丝,孢囊压片可见大量寄生虫孢子,孢子内含有2个明显的“八”字形对称极囊,其形态与粘孢子虫类寄生虫形态特征相似。该孢囊的18S rRNA基因扩增序列(Gen-Bank登录号:KT240127)与碘泡虫(Myxobolus)的18S rRNA序列同源性最高,达92%~97%;在系统发育树中,该孢囊与野鲤碘泡虫(Myxobolus koi)(GenBank登录号为FJ841887和KJ725077)聚为一族。组织病理学观察发现:野鲤碘泡虫以大孢囊的形式仅寄生于鳃弓和鳃丝,形成巨大的寄生虫孢囊,囊内包裹大量成熟孢子;鳃小片增生和坏死,可见大量炎性细胞浸润,表现为寄生虫性、增生性和坏死性鳃炎。【结论】野鲤碘泡虫为本次引起镜鲤鳃乳白色赘生物的病原。本研究首次探讨了野鲤碘泡虫感染镜鲤的寄生类型和病理损伤机制,可为野鲤碘泡虫的致病机制研究提供理论支撑。[Purpose]To identify the pathogen of diseased mirror carp(Cyprinus carpio L.)characterized by white neoplasm on gills in a farm of Sichuan Province,and to explore the pathological effects on gills,providing a scientific knowledge for diagnosis and prevention of this disease.[Methods]Fish with typical symptoms were sampled and dissected.Pathogens(including bacteria,fungi and parasites)were detected using normal methods and identified by molecular methods.Gills were further used for histopathological observation to reveal the pathogenicity.[Results]No bacteria were isolated from the spleen and kidney of diseased fish,while fungal hyphae were observed in the gill filament.A large number of parasite spores could be seen in the gill filament tablet.Two obvious“eight”shaped symmetrical polar cysts were observed in the spores,which were similar to the myxozoans.The similarity of 18S rRNA between Myxobolus reported and the present(GenBank accession number:KT240127)species was from 92%to 97%and clustered into one family with Myxobolus koi(GenBank accession numbers were FJ841887 and KJ725077).Histopathologically,sporocysts were only found on the gill arch and gill filament,but not in other organs.A large number of mature spores compacted in the parasitic cysts were observed.The gill lamellae exhibited hyperplasia and necrosis,with significant infiltration of inflammatory cells,manifesting as parasitic,proliferative,and necrotic gill disease.[Conclusion]M.koi is the pathogen of the present case.The parasitic type and pathological damage mechanism of M.koi in C.carpio are explored.All results will provide theoretical support for the study of the pathogenic mechanism of M.koi of C.carpio.

关 键 词：镜鲤 野鲤碘泡虫 组织病理 系统发育分析 

分 类 号：S941.513[农业科学—水产养殖]