EXPLORING ONTOGENETIC CHANGES IN THE GUT MICROBIOMES OF TWO COMMON FISH & THEIR CONNECTIONS TO NUTRIENT EXCRETION

Fish make significant contributions to the cycling of nutrients within aquatic ecosystems, and traits such as  body size, phylogeny, and trophic level impact the quality and quantity of excretion from consumers. Previous studies have shown environmental and organismal traits impact the gut microbiomes of consumers. However, few studies have examined ontogenetic trends in fish gut microbiomes and how gut microbiomes influence nutrient cycling. Understanding the relationship between gut microbiome and developmental stage may be important for understanding nutrient cycling by fish.   We conducted an exploratory study on the gut microbiomes of two fish species common in the Midwest USA, gizzard shad (Dorosoma cepedianum) and bluegill (Lepomis macrochirus), throughout their development. Both species undergo diet shifts with age. We collected 8 fish per age class (larvae, 1-year old, and 2+ year old) of each species every month from May-September in Acton Lake (Ohio). Gut microbial communities were studied via amplicon sequencing of the 16s rRNA. Additional 16S rRNA libraries were collected from lake water and sediment.   Our project explores the community composition of the microbiome through fish development, with an emphasis on dietary transitions, as well as how the environmental microbial communities and geochemistry influence the gut microbiome. We aim to also relate microbial community composition to the excretion rates of nitrogen (N) and phosphorus (P) in each age class. This builds a foundation for future work that links the role of microbiomes to ecosystem processes.

Primary Presenter: Carrie Ann Sharitt, Miami University (OH) (sharitca@miamioh.edu)

Authors:

Carrie Ann Sharitt, Miami University (OH)  (sharitca@miamioh.edu)

Matthew Saxton, Miami University (OH)  (saxtonm@miamioh.edu)

Michael Vanni, Miami University (OH)  (vannimj@miamioh.edu)