Division of Environmental Dynamics, Graduate School of Environmental Sciences, The University of Shiga Prefecture, Hassaka, Hikone, Shiga522-8533, Japan.
Laboratorio de Parasitología, INIBIOMA (CONICET-Univ. Nac. del Comahue), Quintral 1250, (8400) San Carlos de Bariloche, Río Negro, Argentina.
Parasitology. 2022 Feb;149(2):234-238. doi: 10.1017/S0031182021001736. Epub 2021 Oct 18.
The transmission of adult parasites from prey to predatory hosts has been demonstrated for some acanthocephalan and one cestode species. Derogenes lacustris (Digenea: Hemiuroidea: Derogenidae) is a generalist parasite that infects, as an adult, the stomach of native and introduced freshwater fishes in Andean Patagonia. In the present work, the post-cyclic transmission of D. lacustris from native Galaxias maculatus (Galaxiidae) to introduced Oncorhynchus mykiss (Salmonidae) was proved experimentally. The observed transmission rate for this experimental infection was 19%. The body length of D. lacustris on day 14 post-infection was significantly greater than before transmission. The number of eggs also increased significantly after transmission, showing that D. lacustris can survive, grow and continue with egg production for at least 2 weeks in predatory salmonids. This study provides the first experimental evidence of post-cyclic transmission of trematodes and the results suggest that post-cyclic parasitism enables this species to broaden its range of hosts and distribution ranges in Argentinean Patagonia.
已证明，一些棘头虫和一种绦虫的成虫可以将寄生虫从猎物传播给捕食性宿主。Derogenes lacustris（双腔科：半棘头虫科）是一种寄生在安第斯巴塔哥尼亚地区本地和引入的淡水鱼类胃中的寄生虫。在本研究中，通过实验证明了 Derogenes lacustris 从本地 Galaxias maculatus（加拉西亚科）到引入的 Oncorhynchus mykiss（鲑科）的循环后传播。这种实验感染的观察到的传播率为 19%。感染后 14 天，D. lacustris 的体长明显大于传播前。传播后卵的数量也显著增加，表明 D. lacustris 可以在至少 2 周的时间内在捕食性鲑鱼中存活、生长并继续产卵。本研究提供了循环后吸虫传播的第一个实验证据，结果表明循环后寄生虫感染使该物种能够扩大其宿主范围和分布范围在阿根廷巴塔哥尼亚地区。
