Diet and other environmental factors shape the bacterial communities of fish gut in an eutrophic lake.

AIMS: The aim of this work was to study the gut microbial diversity from eight species of wild fish with different feeding habits, digestive physiology (gastric vs. agastric) and provide comparative structural analysis of the microbial communities within their environment (food items, water, sediments, and macrophytes).

METHODS AND RESULTS: The microbiota of fish gut and their prey items were studied using next generation high-throughput sequencing of the 16S ribosomal RNA genes. A scatter plot based on PCoA scores demonstrated the microbiota formed three groups: 1) stomach and intestinal mucosa, 2) stomach and intestinal content, and 3) prey and environment. Comparisons using ANOSIM showed significant differences among intestinal content of omnivorous, zoobenthivorous, zooplanktivorous-piscivorous fishes (p ≤ 0.1). No significant difference was detected for mucosa from the same groups (p > 0.1).

CONCLUSIONS: Neither the interspecies differences in fish diet nor their phylogenetic position had any effect on the microbiome of the intestinal mucosa, but diet did influence the composition of the microbiota of the intestinal content.

SIGNIFICANCE AND IMPACT OF STUDY: The data demonstrate that fish harbored specific groups of bacteria that do not completely reflect the microbiota of the environment or prey. This article is protected by copyright. All rights reserved.