Belden Lisa K, Widder Pamela D, Fischer Lauren R, Carter Ashlee B, Wojdak Jeremy M
Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA.
Parasitol Res. 2009 Sep;105(3):883-5. doi: 10.1007/s00436-009-1510-1. Epub 2009 Jun 10.
Environmental cues are used by many organisms to time life history transitions and can be important for trematode host location. However, while much is understood about how larval trematodes locate hosts, much less is known about the potential role of host cues in the timing of trematode egg development and hatching. We addressed the potential role of host chemical cues in mediating hatching of Echinostoma trivolvis miracidia by comparing hatching in response to cues from the first intermediate host (the snail Planorbella trivolvis), a non-host snail (the snail Goniobasis proxima), and a non-host invertebrate (earthworm, Lumbricus terrestris). We hypothesized that in the presence of cues from their first intermediate host, E. trivolvis would hatch sooner and would be more synchronized than when host cues were absent. However, we found that hatching was unaffected by our cue treatments. In all treatments, hatching uniformly began at 13 days and was nearly evenly spread over the next 3 weeks.
许多生物体利用环境线索来安排生活史转变的时间，这对于吸虫寻找宿主可能很重要。然而，虽然我们对幼虫吸虫如何定位宿主了解很多，但对于宿主线索在吸虫卵发育和孵化时间方面的潜在作用却知之甚少。我们通过比较棘口吸虫（Echinostoma trivolvis）毛蚴对第一中间宿主（扁卷螺Planorbella trivolvis）、非宿主蜗牛（近三角蚌Goniobasis proxima）和非宿主无脊椎动物（蚯蚓Lumbricus terrestris）的线索的反应来探讨宿主化学线索在介导棘口吸虫毛蚴孵化中的潜在作用。我们假设，在有来自第一中间宿主的线索存在时，棘口吸虫的孵化会比没有宿主线索时更早开始，且更加同步。然而，我们发现孵化不受我们的线索处理的影响。在所有处理中，孵化均在13天开始，并且在接下来的3周内几乎均匀分布。
