CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China.
CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Invertebr Pathol. 2021 Jan;178:107523. doi: 10.1016/j.jip.2020.107523. Epub 2020 Dec 21.
The parasitic dinoflagellates of the Hematodinium genus have impacted wild and cultured stocks of commercial crustaceans worldwide. In the past decade, outbreaks of Hematodinium epizootics resulted in substantial mortalities in cultured Chinese swimming crabs Portunus trituberculatus in the polyculture ponds located in Shandong Peninsula, whereas the source and transmission of the parasite in the polyculture pond system remains to be determined. During April to December of 2018, 2034 crabs and 108 shrimps were collected from the polyculture pond systems in the highly endemic area of Hematodinium diseases in Qingdao, Shandong Province. Among those, 188 individuals of the 6 crab species were infected by the parasite, including 4 novel host species (Uca arcuate, Hemigrapsus penicillatus, Helice wuana and Macrophthalmus japonicas). No infection was identified in Penaeus monodon. Further phylogenetic analyses indicated that the Hematodinium isolate infecting the six crab hosts, together with other isolates reported from China, composed the genotype II of Hematodinium perezi. The parasite was more infectious to cultured Portunus trituberculatus and the dominant wild crab Helice tientsinensis dwelling in the waterways connecting to the polyculture ponds, even though it was found to be a host generalist pathogen. The prevalence of Hematodinium perezi infection in Helice tientsinensis was higher than that of other wild crabs and showed significant positive correlation with that of the cultured Portunus trituberculatus. The results indicated that the wild crabs, particularly Helice tientsinensis, were the important alternate hosts closely involved in transmission and spreading of the Hematodinium disease in the polyculture pond systems.
寄生性甲藻属的寄生虫已在全球范围内影响了野生和养殖的商业甲壳类动物。在过去的十年中，造血虫病的爆发导致了山东半岛养殖三疣梭子蟹的大量死亡，而寄生虫在多营养池塘系统中的来源和传播仍有待确定。2018 年 4 月至 12 月，在山东省造血虫病高度流行地区的多营养池塘系统中采集了 2034 只螃蟹和 108 只虾。在这些螃蟹中，有 6 种螃蟹的 188 个个体感染了寄生虫，包括 4 种新的宿主物种（弧形招潮蟹、日本对虾、拟穴青蟹和日本沼虾）。凡纳滨对虾未感染。进一步的系统发育分析表明，感染 6 种蟹宿主的造血虫分离株与中国其他报道的分离株一起构成了造血虫 perezi 的基因型 II。这种寄生虫对养殖的三疣梭子蟹和栖息在与多营养池塘相连的水道中的优势野生蟹天津厚蟹具有更高的感染力，尽管它被认为是一种宿主泛性病原体。天津厚蟹的造血虫 perezi 感染率高于其他野生蟹，与养殖的三疣梭子蟹呈显著正相关。结果表明，野生蟹，特别是天津厚蟹，是多营养池塘系统中造血虫病传播和扩散的重要替代宿主。
