An evaluation of methods to study the gut bacterial community composition of freshwater zooplankton.
2008 (English)In: Journal of Plankton Research, ISSN 0142-7873, Vol. 30, no 9, 997-1006 p.Article in journal (Refereed) Published
The occurrence of gut bacteria in freshwater and marine zooplankton has long been recognized, but knowledge about the composition of the gut "microflora" and its permanent presence in different zooplankters is still inadequate. In this study, we tested the suitability of fluorescence in situ hybridization (FISH), catalysed reporter deposition (CARD)-FISH, cultivation and transmission electron microscopy (TEM) on homogenates and whole-specimen sections to assess the presence and identity of gut bacteria in several freshwater copepod and cladoceran species. Unambiguous results about the presence of a permanent gut "microflora" were obtained for freshly caught Daphnia pulex by TEM. CARD-FISH on gut homogenates from Acanthodiaptomus denticornis and D. pulex revealed a very similar bacterial composition to that present in the water column. Major bacterial groups found in cladocerans and copepods were alpha-, beta-, gamma-Proteobacteria and Cytophaga–Flavobacteria. The high contribution of alpha-Proteobacteria in A. denticornis suggested a specific niche for this group, but probably in association with its carapace. FISH on paraffin semithin sections had the potential to provide quantitative and qualitative information about the composition of the gut "microflora", but loss of bacteria and gut content was significant.
Place, publisher, year, edition, pages
2008. Vol. 30, no 9, 997-1006 p.
IdentifiersURN: urn:nbn:se:uu:diva-107699DOI: 10.1093/plankt/fbn061OAI: oai:DiVA.org:uu-107699DiVA: diva2:232508