Parasite infectious stages provide essential fatty acids and lipid-rich resources to freshwater consumers.

摘要: Free-living parasite infectious stages, such as motile cercariae of trematodes (flatworms), can constitute substantial biomass within aquatic ecosystems and are frequently eaten by various consumers, potentially serving an important source nutrients energy. However, quantitative data on their nutritional value (e.g., essential fatty acids [EFA]) largely lacking. As EFA leading indicators quality underpin ecosystem productivity, we performed acid (FA) analysis aggregate ~ 30,000 the freshwater trematode, Ribeiroia ondatrae. Individual contained 15 ng total FA, considerable quantities EFA, including eicosapentaenoic (EPA, at 0.79 ng cercaria−1) docosahexaenoic (DHA, 0.01 ng acids. We estimated annual production R. ondatrae for a series ponds in California to be 40.4–337.0 μg m−2 yr−1 EPA 0.7–6.2 μg m−2 yr−1 DHA. To investigate viability prey, also compared growth FA profiles dragonfly larvae (naiads Leucorrhinia intacta) fed equivalent masses either or zooplankton (Daphnia spp.) 5 weeks. Naiads raised two diets grew equally well, with no significant differences found profiles. While widely recognized vital energy, conduit movement between algae higher trophic levels, suggest similar role trematode ‘unlocking’ from benthic environment, highlighting potential importance nutrient that supports animal health.