Journal of Aquaculture Research & Development

Variation in intestinal microbiome of channel catfish (Ictalurus punctatus) across ontogeny

International Conference on Aquaculture & Fisheries

July 20-22, 2015 Brisbane, Australia

Jacob W Bledsoe

Posters-Accepted Abstracts: J Aquac Res Development

Abstract:

Research on pre and probiotics in aquaculture has been limited by a lack of basic knowledge regarding intrinsic fluctuations that occur in the intestinal microbiome (IM) of fish across developmental ontogeny. Without such knowledge, delineating the significance of modifications to the IM or identifying dysbiosis may be difficult because data is lacking on the natural variations that occur within the microbial community. To improve our knowledge, this study characterized the IM of a single family of the important US. aquaculture species, channel catfish Ictalurus punctatus, under controlled conditions. Samples were taken at 2, 64, 124, and 193 dph. Sac-fry (2 dph) were ground whole while at all other time points the entire intestinal tract was removed and homogenized using sterile procedures (n=10). Adherent and allochthonous IM DNA along with DNA from all feeds and tank water was then extracted and added to the Fluidigm Access Array for PCR amplification of the 16S rRNA gene, barcoded primer addition and library preparation for identification of bacterial, fungal and archaeal biota. Sequencing was performed on the MiSeq 2000 and data were analyzed using QIIME with the Green genes database for cross-referencing of operational taxonomic units. Ontogenetic changes in the IM may be attributed to host immunity-IM interactions plus changes in diet formulations. These results enable a better understanding of the homeostatic variation of the IM allowing more accurate interpretations of shifts caused by exogenous influences. This data set may also be used in the future to identify candidate microbial species for use as probiotics.