Behaviours in trematode cercariae that enhance parasite transmission: patterns and processes
Behaviours in trematode cercariae that enhance parasite transmission: patterns and processes
复制标题
吸虫尾蚴增强寄生虫传播的行为：模式和过程
作者：
C. Combes;A. Fournier;H. Moné;A. Théron
尾蚴和毛虫一样，都是非寄生幼虫阶段，在所有吸虫的生活史中都涉及到宿主到宿主的寄生虫传播。几乎所有的尾蚴都可以自由生活在外部环境中。除了少数例外(八孔鲍尾蚴可以存活几个月，Shost ak&Esch，1990a)，尾蚴的活动寿命很短，在此期间它们不取食，靠积累的储量生活。大多数尾蚴在第二中间宿主中以囊虫的形式存在，这些第二中间宿主是最终宿主的猎物；在某些物种中，活跃生命的中断是通过外部环境的包囊(在少数物种中是简单的不动等待策略)实现的。在一些双宿主生活史中，尾虫在侵入后发育成成虫(这是导致人类血吸虫病的各种物种的情况)。一些尾蚴不会离开软体动物，而软体动物必须被最终的宿主摄取。
Cercariae, like miracidia, are non-parasitic larval stages implicated in the life cycle of all trematodes for the host-to-host parasite transmission. Almost all cercariae are free-living in the external environment. With a few exceptions (cercariae of Halipegus occidualis (Halipegidae) can live several months, Shostak & Esch, 1990a), cercariae have a short active life during which they do not feed, living on accumulated reserves. Most cercariae encyst as metacercariae in second intermediate hosts which are prey of the definitive host; in certain species, the interruption of the active life is achieved by an encystment in the external environment (or a simple immobile waiting strategy in a few species). In some two-host life cycles, the cercariae develop into adults after penetration (this is the case for various species causing human schistosomiasis). Some cercariae do not leave the mollusc which must then be ingested by the definitive host.