Methodological Approaches Used to Assess Fish Gastrointestinal Communities - Aquaculture Nutrition: Gut Health, Probiotics and Prebiotics - page 116

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Fig. 5.1 Epifluorescence micrographs of the indigenous gut microbiota of fish. (A) In situ hybridization of
rainbow trout gut microbiota with green fluorescein labelled probe EUB338-mix (detecting all bacteria)
(Waines and Merrifield, unpublished data). Despite the clearly identifiable cocci (arrows) and rod-shaped
bacteria (arrowheads) present within the sample, reliable enumeration is difficult due to the dense nature of
the gut contents which leads to poor differentiation between individual cells in some cases. In addition,
non-specific hybridization and fluorescence of background material (digesta and/or mucus) is present
(five-pointed stars). (B) DAPI staining (blue) and in situ hybridization of common carp gut microbiota with
green fluorescein (FITC) labelled probe VA (detecting Aeromonas and Vibrio spp.). (Source: Mark Rawling.)
For colour detail see Plate 10.