Justin Greer Cathy A. Richter Luke R. Iwanowicz Edward Spinard Jacquelyn McDonald Carla M. Conway Robert W. Gale Donald E. Tillitt John D. Hansen Jessica Kristin Leet 2022 <p><span>Disease outbreaks, skin lesions, mortality events, and reproductive abnormalities have been observed in wild populations of centrarchids. The presence of estrogenic endocrine disrupting compounds (EEDCs) has been implicated as a potential causal factor for these effects. The effects of prior EEDC exposure on immune response were examined in juvenile largemouth bass (</span><i>Micropterus salmoides</i><span>) exposed to a potent synthetic estrogen (17α-ethinylestradiol, EE2) at a low (EE2</span>_Low<span>, 0.87 ng/L) or high (EE2</span>_High<span>, 9.08 ng/L) dose for 4 weeks, followed by transfer to clean water and injection with an LD</span>₄₀<span>&nbsp;dose of the Gram-negative bacteria&nbsp;</span><i>Edwardsiella piscicida</i><span>. Unexpectedly, this prior exposure to EE2</span>_High<span>&nbsp;significantly increased survivorship at 10 d post-infection compared to solvent control or EE2</span>_Low<span>-exposed, infected fish. Both prior exposure and infection with&nbsp;</span><i>E. piscicida</i><span>&nbsp;led to significantly reduced hepatic glycogen levels, indicating a stress response resulting in depletion of energy stores. Additionally, pathway analysis for liver and spleen indicated differentially expressed genes associated with immunometabolic processes in the mock-injected EE2</span>_High<span>&nbsp;treatment that could underlie the observed protective effect and metabolic shift in EE2</span>_High<span>-infected fish. Our results demonstrate that exposure to a model EEDC alters metabolism and immune function in a fish species that is ecologically and economically important in North America.</span></p> application/pdf 10.1021/acs.est.2c02250 en ACS Publications Exposure to 17α-ethinylestradiol results in differential susceptibility of largemouth bass (Micropterus salmoides) to bacterial infection article