Largemouth base histological development and transcriptomic changes in gonad tissue after early life stage exposure to Atrazine (1-Chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine) or the model estrogen 17α-ethinylestradiol.

Physiological endpoints observed in adult largemouth bass in response to an EE2 (17 alpha-ethinylestradiol) or mixture of estrone and atrazine exposure under laboratory pond conditions. Also included are water quality and chemical concentration data. Adult LMB were exposed in outdoor pond mesocosms from post-spawning to early gonad recrudescence to either EE2 (2.4 nanograms per liter), or a mixture of endocrine-active substances commonly detected in the Chesapeake Bay watershed, atrazine (5.4 micrograms per liter) and estrone (47.9 nanograms per liter). Male reproductive condition, sperm count, and sperm motility were assessed.

Disease outbreaks, skin lesions, fish kill events, and reproductive abnormalities have been observed in wild populations of bass in the Chesapeake Bay watershed. Occurrence of synthetic and natural hormones from wastewater treatment plants and livestock operations, pesticides from agricultural lands, and phytoestrogens from cover crops have been implicated as potential causes of these adverse effects. Late summer to fall is the period of early gonad recrudescence in adult bass when spermatogenesis and oogenesis begin for the upcoming spawning event in spring. Our objective was to assess whether early gonad recrudescence was a period of sensitivity for inducing immunomodulation. Adult largemouth bass (LMB; Micropterus salmoides) were exposed in outdoor pond mesocosms from post-spawning (July) through early gonad recrudescence (November) to either a model estrogen, 17alpha-ethinylestradiol (EE2; 2.4 ng/L), a mixture of endocrine-active substances commonly detected in the Chesapeake Bay watershed (MIX; 5.4 µg atrazine/L and 47.9 ng estrone/L), or a solvent control. Immune endpoints including mitogenesis and respiratory burst were assessed in fish sampled during December and April.

Adult largemouth bass have been shown to be sensitive to induction of intersex in response to chronic estrogen exposures over a complete reproductive cycle. Late summer to fall is the period of early gonad recrudescence when spermatogenesis is beginning in preparation for the spawning season in the spring. Our objective was to assess in 2018 whether early gonad recrudescence was a period of sensitivity for induction of intersex and/or alterations in reproductive condition or function. Adult male largemouth bass were exposed in outdoor pond mesocosms from post-spawning to early gonad recrudescence to either 17alpha-ethinylestradiol or to a mixture of endocrine-active substances commonly detected in the Chesapeake Bay watershed (atrazine and estrone). Gonad samples were sent overnight to Wetland and Aquatic Research Center laboratories and sperm motility was measured by computer assisted sperm motion analysis. Overall, male reproductive condition, sperm count, and sperm motility were analyzed.

The data was gathered to document the extent and severity of biomarkers of exposure to estrogenic chemicals in smallmouth and largemouth bass. Samples were collected from 2004 through 2010 at sites in five watersheds within the Chesapeake Bay watershed. A total of 281 largemouth bass were collected from the Potomac, Susquehanna, Patuxent and Rappahannock rivers and 1,384 smallmouth bass from the Potomac, Susquehanna and James. Fish were collected by boat electroshocking, euthanized in the field, weighed, measured, a blood samples collected and a necropsy completed that included documenting any visible abnormalities and collecting tissues for histopathology. Plasma obtained from blood samples was analyzed for vitellogenin, a yolk precursor widely used as an indicator of estrogenic exposure in immature and male fishes. Five to seven sections of testes were processed for microscopic analyses, embedded in paraffin, sectioned at 5 µm, stained with hematoxylin and eosin. The presence of testicular oocytes was noted and the severity rated from 1 to 4 based on number and arrangement of oocytes.

Supporting information for "Kadlec, S.M., Blackwell, B.R., Blanksma, C.A., Johnson, R.D., Olker, J.H., Schoff, P.K. and Mount, D.R. (2022), Gonadal Development in Smallmouth Bass (Micropterus Dolomieu) Reared in the Absence and Presence of 17-α-Ethinylestradiol. Environ Toxicol Chem, 41: 1416-1428. https://doi.org/10.1002/etc.5320". This dataset is associated with the following publication: Kadlec, S., B. Blackwell, C. Blanksma, R. Johnson, J. Olker, P. Schoff, and D. Mount. Gonadal Development in Smallmouth Bass (Micropterus Dolomieu) Reared in the Absence and Presence of 17-α-Ethinylestradiol. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 41(6): 1416-1428, (2022).

Supporting information for "Kadlec, S.M., Blackwell, B.R., Blanksma, C.A., Johnson, R.D., Olker, J.H., Schoff, P.K. and Mount, D.R. (2022), Gonadal Development in Smallmouth Bass (Micropterus Dolomieu) Reared in the Absence and Presence of 17-α-Ethinylestradiol. Environ Toxicol Chem, 41: 1416-1428. https://doi.org/10.1002/etc.5320". This dataset is associated with the following publication: Kadlec, S., B. Blackwell, C. Blanksma, R. Johnson, J. Olker, P. Schoff, and D. Mount. Gonadal Development in Smallmouth Bass (Micropterus Dolomieu) Reared in the Absence and Presence of 17-α-Ethinylestradiol. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 41(6): 1416-1428, (2022).

The data were gathered as a preliminary assessment of estrogenicity under base-flow conditions at over 100 sites (lakes and streams) throughout New Jersey followed by more targeted sampling of smallmouth bass at nine sites with varying levels of estrogenicity. In 2016, 102 sites (lakes and streams) for the preliminary estrogenicity assessment were selected utilizing compiled results of previous monitoring studies (chemical and biological), current sampling networks, and other areas of concern based on input from stakeholders. Discrete grab surface water samples were collected under base-flow conditions in the fall of 2016 and analyzed for levels of estrogenicity using a bioluminescent yeast screen. Water samples for estrogenicity were also collected from the nine health sites in April/May of 2017 in combination with fish sampling and again in November 2017 under base flow conditions. In the spring of 2017, 20 adult smallmouth bass were collected from each of the nine sites (two river and seven reservoir sites). Fish were collected by boat electroshocking, euthanized in the field, weighed, measured, a blood sample collected and a necropsy completed that included documenting any visible abnormalities and collecting tissues for histopathology. Plasma obtained from blood samples was analyzed for vitellogenin, a yolk precursor widely used as an indicator of estrogenic exposure in immature and male fishes. Five to seven sections of testes were processed for microscopic analyses, embedded in paraffin, sectioned at 5 µm, stained with hematoxylin and eosin. The presence of testicular oocytes was noted and the severity rated from 1 to 4 based on number and arrangement of oocytes.

Intersex in small- and largemouth bass has been observed in the upper Chesapeake Bay Watershed since 2003. This observation is indicative of exposure to estrogenic endocrine disrupting chemicals. In order to complement biological data sets and better identify the spatial and temporal nature of this end-point, discrete grab water samples were collected throughout the upper Chesapeake Bay Watershed for the evaluation of estrogenic activity. Data reported here are estrogenicity values derived from bioassay screening of OASIS-HLB extracts discrete grab water samples. Estrogenicity was determined using a bioluminescent yeast estrogen screen. Here we report estrogenicity data for selected sites in the Chesapeake Bay water shed collected between 2008 and 2011.

In the present study, features of gonad metabolite profiles associated with TO in largemouth bass (LMB, Micropterus salmoides) from an impoundment in Georgia (USA) were determined using GC–MS-based metabolomics. Clinical blood biochemical screens were used to evaluate markers of fish health associated with TO. Results suggest that physiological changes in energy expenditure as well as relatively ‘feminized’ gonad lipid and protein metabolism may be related to the occurrence of TO in male LMB, and highlight the need to understand relationships between intersex and physical stressors such as elevated temperature and hypoxia. These results provide novel insight to AOPs associated with TO and identify candidate analytes for biomarker discovery. This dataset is not publicly accessible because: Data belongs to coauthor at University of Georgia. It can be accessed through the following means: Data can be accessed by contacting the corresponding author (bringo@uga.edu). Format: excel. This dataset is associated with the following publication: Urich, M., W. Henderson, A. MacLeod, L. Yonkos, and R. Bringolf,. Gonad metabolomics and blood biochemical analysis reveal differences associated with testicular oocytes in wild largemouth bass (Micropterus salmoides). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY - PART B: BIOCHEMISTRY & MOLECULAR BIOLOGY. Elsevier Science Ltd, New York, NY, USA, 250: 110491, (2020).