SS1.08 Sensory Ecology, Neurophysiology and Behavior of Zooplankton
Date: Monday, June 10, 2002
Time: 11:15:00 AM
Location: Carson B
 
FelsD, Zoological Institute Univ. Basel, Rheinsprung 9, 4051 Basel, Switzerland, daniel.fels@unibas.ch
 
EPIDEMIOLOGY OF TWO HORIZONTALLY TRANSMITTED GUT PARASITES OF DAPHNIA MAGNA
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The study was performed with two clones of Daphnia magna, each with its sympatric microparasite, Glugoides intestinalis or Micro1 (Microsporidia). We tested for the effect of feeding on infection risk (IR) and the effect of vertical or horizontal distance on IR . When uninfected Daphnia are individually placed in (100ml) beakers which previously contained an infected Daphnia, they suffered not from higher IR when we added algea to that beaker compared to those receiving no algae: even though we found an algea concentration-dependent increase in the frequency of mandibular movements. Uninfected Daphnia which we kept in cylindric cages (hight: 10cm; diameter: 4cm) allowing water movements in all directions suffered from the same IR irrespective from two possible distances to infected Daphnias which were in cages as well. The distances were 1cm aside infected Daphnia and 10cm away in either vertical or horizontal direction. We assume these latter results to be due to the effect of filtration movements of Daphnia on the surrounding water.