Conclusion
    The presence of atrazine in the Chesapeake Bay may be selecting for pathogenic bacterial groups to reside within the oysters of the Chesapeake Bay and its tributaries. The effects of this compositional shift remain unclear, therefore, future research efforts should focus on understanding the relationship between biocidal herbicides and oyster-prokaryote interactions.  Extended experiments with more time points, as well as repeated challenges, would help to further elucidate the role of oyster-associated microbial communities to the overall physiological functioning of the host. This research provides a vital baseline for future research aimed at understanding the role gut microbes have in oyster physiology. \(\)
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  \(\)Acknowledgements
We would like to thank Horn-point laboratory for providing the spat used throughout the experiment. Dr. Tara Scully for acting as the lead investigator for the project. The George Washington University, for housing the project, and providing the funds necessary for it to be carried out. And finally, to each of the authors for their hard work and perseverance. 
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