Toledo R, Muñoz-Antoli C, Esteban J G
Departamento de Parasitología, Facultad de Farmacia, Universidad de Valencia, Spain.
J Parasitol. 1999 Apr;85(2):263-7.
The production and the chronobiology of emergence of the cercariae of Euparyphium albuferensis from Gyraulus chinensis experimentally infected with a single miracidium were established during 28 consecutive days from the first day of cercarial shedding. Moreover, the effect of a sudden change in light-dark cycling was investigated. Although the daily cercarial shedding rates show great variability, a progressive increase in cercarial production was observed in the first weeks of the cercarial shedding periods, probably in relation to the demography of intramolluscan larval stages. Under 12:12 light-dark cycling conditions, E. albuferensis cercariae emerged in the light, and the rhythm was circadian. The sudden change in the light-dark cycle resulted in corresponding alterations in emergence patterns, which shows that cercarial emergence was correlated to light-dark alternation. The ecological consequences of daily emergence by mobile cercariae whose target hosts are organisms that regularly occur in the same habitat with the molluscan emitting host, such as those of E. albuferensis, are discussed with reference to the hypotheses proposed to date, and an alternative hypothesis is proposed.
从感染单个毛蚴的中华圆扁螺中产出阿尔布费拉真杯尾吸虫尾蚴的产量及发生时间生物学，是在尾蚴开始排出的第1天起的连续28天内确定的。此外，还研究了光暗循环突然变化的影响。尽管每日尾蚴排出率变化很大，但在尾蚴排出期的最初几周观察到尾蚴产量逐渐增加，这可能与螺内幼虫阶段的种群统计学有关。在12:12光暗循环条件下，阿尔布费拉真杯尾吸虫尾蚴在光照下出现，节律为昼夜节律。光暗循环的突然变化导致出现模式相应改变，这表明尾蚴出现与光暗交替相关。针对移动尾蚴每日出现的生态后果进行了讨论，其目标宿主是与排放尾蚴的软体动物宿主在同一栖息地经常出现的生物，如阿尔布费拉真杯尾吸虫的宿主，参考了迄今为止提出的假设，并提出了另一种假设。
