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ARS Home » Southeast Area » Stoneville, Mississippi » Warmwater Aquaculture Research Unit » Research » Publications at this Location » Publication #320947
Title: Evaluating differences in the homeostatic intestinal microbiome between selected strains of catfish Ictalurus punctatus and blue catfish Ictalurus furcatus

Author
item BLEDSOE, J - Southern Illinois University
item Peterson, Brian
item SWANSON, KELLEY - Southern Illinois University
item SMALL, BRIAN - Southern Illinois University

Submitted to: Annual Meeting World Aquaculture Society
Publication Type: Abstract Only
Publication Acceptance Date: 9/10/2015
Publication Date: 2/22/2016
Citation: Bledsoe, J.W., Peterson, B.C., Swanson, K.S., Small, B.C. 2016. Evaluating differences in the homeostatic intestinal microbiome between selected strains of catfish Ictalurus punctatus and blue catfish Ictalurus furcatus. Annual Meeting World Aquaculture Society. P. 78.

Interpretive Summary:

Technical Abstract: The intestinal microbiome (IM), or the community of commensal and pathogenic microbes living within the gut, have long been thought to play a large role in digestion and fish performance. Recently, high-throughput molecular sequencing has yielded insights into the importance of the IM in aquaculture species, and it has been shown that an imbalanced microbiome, or dysbiosis, can lead to disease or poor digestion. While it has been hypothesized that host (fish) genetics and immunity play a large role in maintaining the specific microbes within the microbiome, little data exists to elucidate this relationship in fish. To improve upon this knowledge, we raised three strains of Channel Catfish Ictalurus punctatus and four strains of Blue Catfish Ictalurus furcatus from eggs, with equal feed and water conditions, to 193 days post hatch. At this time, ten fish from each strain were euthanized and the entire intestinal tract was removed and homogenized using sterile procedures. This allowed both allochthonous (fecal) and autochthonous (mucosal) bacteria to be captured for DNA extraction using MoBio PowerFecal® DNA Extraction Kit. DNA was then added to the Fluidigm Access Array system for PCR amplification of the 16S rRNA gene, and preparation of a multiplexed sequencing library. Sequencing was then preformed on the MiSeq 2000 platform and data were analyzed using QIIME with the GreenGenes database used for picking of operational taxonomic units (OTUs). Poor quality reads and low abundance (=0.5%) OTUs were removed, leaving 21 samples from both fish species for analysis. From this data a total of 3,168,821 OTUs were identified from 14 distinct phylogentic clades. While the dominant OTUs of the IMs are similar, the relative abundances of these OTUs are statistically different across the two species of Ictalurids. This study provides insight on the relationship of fish genetics with the IM, and may help to explain differential susceptibility to disease in Ictalurids.