Platt T R, Villanueva S D
Department of Biology, Saint Mary's College, Notre Dame, Indiana 46556, USA.
J Parasitol. 1995 Dec;81(6):1024-7.
Postmortem migration is of considerable concern in surveys and studies of parasite ecology where accurate estimates of parasite location is crucial. Yet, there is no quantitative information documenting this phenomenon. Twenty-seven Sprague-Dawley rats were each inoculated with 5 cysticercoids of Hymenolepis diminuta. Four weeks postinfection, 15 rats were killed by cervical dislocation. The small intestines of 3 rats were removed immediately and fast frozen. Additional groups of 3 rats each (experimentals) were processed at intervals of 30, 60, 120, and 240 min after death (AD). Four additional groups of 3 rats (controls) were killed and processed at 30, 60, 120, and 240 min in order to assess changes due to circadian movement. Changes in the position of the scolex and biomass (dry weight) were assessed as a proportion of small intestine length for the following criteria: anterior, median, and posterior location. The only significant within-group difference was an anterior shift in median biomass in the experimental group. Between-group differences were not evident at 30 min. Significant posterior shifts were found in anterior and median scolex position of the experimentals at 120 and 240 min AD, respectively. Median and posterior biomass shifted significantly anteriorly at 60 and 120 min AD in the experimental group, respectively, and worm range was significantly reduced in the experimentals at 120 min AD. There appears to be a 30-min period following host death in which H. diminuta does not change its position within the rat small intestine.
在寄生虫生态学的调查和研究中，死后迁移是一个相当令人担忧的问题，因为准确估计寄生虫的位置至关重要。然而，目前尚无记录这一现象的定量信息。27只Sprague-Dawley大鼠每只接种5个微小膜壳绦虫的囊尾蚴。感染后4周，15只大鼠通过颈椎脱臼处死。立即取出3只大鼠的小肠并速冻。另外每组3只大鼠（实验组）在死后30、60、120和240分钟（AD）进行处理。另外4组每组3只大鼠（对照组）在30、60、120和240分钟处死并进行处理，以评估昼夜节律运动引起的变化。根据以下标准，将头节位置和生物量（干重）的变化评估为小肠长度的比例：前部、中部和后部位置。唯一显著的组内差异是实验组中部生物量向前移动。在30分钟时，组间差异不明显。在死后120分钟和240分钟，实验组的前部和中部头节位置分别显著向后移动。在死后60分钟和120分钟，实验组的中部和后部生物量分别显著向前移动，并且在死后120分钟，实验组的虫体范围显著缩小。宿主死亡后似乎有一个30分钟的时间段，在此期间微小膜壳绦虫在大鼠小肠内不会改变其位置。
