Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Dongling Road 120, Shenyang 110866, PR China.
Dis Aquat Organ. 2021 May 6;144:143-150. doi: 10.3354/dao03579.
In this study, we describe in detail the life cycle of Tachaea chinensis (Isopoda: Corallanidae), a branchial ectoparasitic isopod that infests the freshwater shrimp Palaemonetes sinensis in China. We obtained 14 ovigerous T. chinensis females (8.22-11.92 mm in length) and observed the development of embryos through 5 sequential ontogenetic stages within the brood pouches (marsupium) of these females. The number of eggs or mancae (post-larval juveniles) held in the female marsupium ranged from 31 to 86, with a mean ± SD of 61.25 ± 16.16 eggs. Female T. chinensis were semelparous, i.e. individuals died following the release of mancae from the marsupium. Released mancae were non-planktonic and immediately infective to host shrimps. However, only a few mancae successfully established contact with a host, and it is thus assumed that the remainder were predated by shrimp. Attached T. chinensis fed on the host hemolymph, and subsequent to host death, these isopods typically searched for a new host. We also found that T. chinensis exhibits a host preference: most mancae attached to P. sinensis rather than to Neocaridina sp. or Macrobrachium nipponense. This study provides valuable empirical data that will support future research on the prevention and control of parasitic isopod infections.
在这项研究中，我们详细描述了中国淡水虾中华绒螯蟹鳃外寄生等足类动物中华栉水虱的生活史。我们获得了 14 只抱卵的中华栉水虱雌性个体（体长 8.22-11.92 毫米），并观察了这些雌性个体的育幼袋（育幼囊）内胚胎的 5 个连续的个体发生阶段的发育过程。雌性育幼囊内的卵或幼体（后期幼体）数量为 31 至 86 个，平均值±标准差为 61.25±16.16 个。中华栉水虱是一次性产卵的，即个体在幼体从育幼囊释放后死亡。释放的幼体是非浮游的，并且立即对宿主虾具有感染力。然而，只有少数幼体成功与宿主建立联系，因此其余的幼体可能被虾捕食了。附着的中华栉水虱以宿主的血淋巴为食，并且在宿主死亡后，这些等足类动物通常会寻找新的宿主。我们还发现，中华栉水虱表现出宿主偏好：大多数幼体附着在中华绒螯蟹上，而不是在秀丽白虾或日本沼虾上。这项研究提供了有价值的经验数据，将支持未来对寄生虫等足类感染的预防和控制的研究。
