摘要: |
寄生性病原血卵涡鞭虫(Hematodinium sp.)逐渐成为危害我国沿海养殖三疣梭子蟹、锯缘青蟹、脊尾白对虾等蟹虾类的致病性病原。为研究血卵涡鞭虫在我国北方的感染、流行情况, 2012 年7—11 月间, 作者从山东半岛三疣梭子蟹的主要养殖区域和邻近海域随机采集梭子蟹样品, 进行了血淋巴、组织病理、电镜和分子生物学检测, 首次在从胶南和莱州湾养殖区采集的梭子蟹中发现了血卵涡鞭虫感染。在感染血卵涡鞭虫的梭子蟹血淋巴中, 共发现了该寄生性病原的四个生活史阶段: 丝状滋养体、单细胞滋养体、滋养体聚合体和多核孢子体; 该区域发现的血卵涡鞭虫(Hematodinium sp.)形态上与其他报道Hematodinium spp.类似, 与在我国东南沿海报道发现的血卵涡鞭虫有亲密的遗传关系; 人工感染实验表明该寄生性虫具感染性并对宿主的主要器官造成显著的病理变化。该研究表明血卵涡鞭虫感染养殖蟹类不仅局限于我国东南沿海, 在我国北方的养殖蟹类中也存在; 这些养殖区普遍采用的混合养殖模式可能一定程度上加剧了该寄生性病原的传播、扩散, 因此其传播扩散方式亟需进一步调查研究。 |
关键词: 寄生性甲藻 混合养殖 传播途径 生活史 遗传分析 |
DOI:10.11693/hyhz20130600083 |
分类号: |
基金项目:国家基金委青年科学基金项目,41206145,41206162号;海洋公益性行业科研专项经费项目,201005015-01;国家基金委创新研究群体科学基金项目,41121064号。 |
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PRELIMINARY STUDY OF HEMATODINIUM INFECTIONS IN CULTURED CHINESE SWIMMING CRAB PORTUNUS TRITUBERCULATUS IN SHANDONG PENINSULA, CHINA |
LI Cai-Wen1, SONG Shu-Qun1, LIU Yun1, WANG Jin-Feng1,2, XIAO Jie3
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1.Key Lab of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;2.Graduate University of Chinese Academy of Sciences, Beijing 100049, China;3.The First Institute of Oceanology, SOA, Qingdo 266061, China
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Abstract: |
Parasitic dinoflagellates Hematodinium has become a threatening pathogen in cultured Portunus trituberculatus, Scylla serrate, and Exopalaemon carinicauda along coastal areas of southern China. However, no Hematodinium infections had been reported in northern China. In 2012, we sampled P. trituberculatus in polycuture ponds and adjacent coastal waters from two sites in Shandong Peninsula. Hematodinium infections were identified in 4 crabs collected randomly from polyculture ponds, while no infections were observed in wild crabs from adjacent coastal waters. Filamentous trophont, uninucleate trophont, trophont clumps, and multinucleate sporonts were observed in hemolymph of diseased crabs. The Hematodinium sp. shares similar morphologic features and caused typical pathological changes in major tissues of infected hosts as other Hematodinium spp. The laboratory trials indicated that this parasite was infectious and caused similar pathological alterations to crab hosts. Molecular analysis indicated the Hematodinium isolates were closely related to those reported in southern China. Our findings indicate an alarmingly broad distribution of the infectious pathogen along the coastal areas of China. The polyculture pond system that are widely used in those culture regions in China may prompt transmission or spread of Hematodinium among susceptible hosts, which urges further investigation of its major routes of transmission in such a culture system along with better understanding of its life cycle. |
Key words: parasitic dinoflagellate polyculture transmission life cycle phylogenetic analysis |