Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)

Bibliographic Details
Main Author: Sovic, David M.
Language:English
Published: The Ohio State University / OhioLINK 2016
Subjects:
Online Access:http://rave.ohiolink.edu/etdc/view?acc_num=osu1459774776
id ndltd-OhioLink-oai-etd.ohiolink.edu-osu1459774776
record_format oai_dc
collection NDLTD
language English
sources NDLTD
topic Environmental Science
Biology
Toxicology
Wildlife Conservation
spellingShingle Environmental Science
Biology
Toxicology
Wildlife Conservation
Sovic, David M.
Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
author Sovic, David M.
author_facet Sovic, David M.
author_sort Sovic, David M.
title Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
title_short Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
title_full Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
title_fullStr Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
title_full_unstemmed Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae)
title_sort estrogens, endocrine disruption, and approaches to assessing gametogenesis and reproductive condition in freshwater mussels (bivalvia: unionidae)
publisher The Ohio State University / OhioLINK
publishDate 2016
url http://rave.ohiolink.edu/etdc/view?acc_num=osu1459774776
work_keys_str_mv AT sovicdavidm estrogensendocrinedisruptionandapproachestoassessinggametogenesisandreproductiveconditioninfreshwatermusselsbivalviaunionidae
_version_ 1719439657983279104
spelling ndltd-OhioLink-oai-etd.ohiolink.edu-osu14597747762021-08-03T06:35:19Z Estrogens, Endocrine Disruption, and Approaches to Assessing Gametogenesis and Reproductive Condition in Freshwater Mussels (Bivalvia: Unionidae) Sovic, David M. Environmental Science Biology Toxicology Wildlife Conservation Organisms belonging to the family Unionidae, commonly referred to as freshwater mussels, have, over the last several decades, experienced drastic declines in range and number for a great number of species belonging to this diverse group. While a variety of potentially causative factors have been implicated in the declines, the possibility that environmental contaminants, including those identified as endocrine disrupting chemicals (EDCs), might contribute to these declines is central to this work. Due to the highly endangered nature of many unionid species and a, generally, limited ability to secure and maintain organisms for testing, the ability to assess effects of toxicant exposure in both laboratory and field studies on unionid reproductive condition and gametogenesis using minimally invasive and nonlethal methods is paramount to the ability to gain critical information on these organisms. Historically, methods used to assess reproductive condition and gametogenesis in bivalves have focused on histological analyses, which have most always required organism sacrifice. Recent advances in nonlethal assessment and methodological developments focused on the utilization of nonlethal procedures has, however, provided a new avenue by which evaluation of potential exposure effects in unionids might be conducted. Therefore, this study aimed first to test the ability of a nonlethal gonad biopsy to provide information sufficient for accurate gametogenic assessment of the common unionid, Elliptio complanata and, second, to apply his nonlethal biopsy procedure in the study of unionids both in the laboratory and the field.The ability of the nonlethal biopsy procedure to accurately stage gametogenesis in E. complanata was validated on organisms collected from the Cacapon River, in West Virginia. Strong agreement (Cohen’s kappa scores 0.88 and 0.80 for male and female samples, respectively) was found between gametogenic staging using the biopsy method and a traditional histological approach. The procedure was then applied in the study of three unionid species in the field, including E. complanata, Elliptio dilatata, and the federally endangered Pleurobema clava. Observed gametogenic anomalies were evaluated in light of measures of total estrogenicity of surface waters proximate to each studied population. Polar organic chemical integrative samplers (POCIS) were deployed seasonally at each site and extracts from these passive sampling devices were assayed using the yeast estrogen screen (YES) to determine total estrogenicity associated with surface waters. When detected, estrogenicity of passive sampler extracts was low, and associations between evidence of reproductive impairment in the studied unionid populations with estrogenicity data were weak. In order to further investigate a relationship between estrogen exposure and Unionid gamete development, the biopsy procedure was employed in an investigation of 17ß-estradiol (E2) exposure effects on gametogenesis in Elliptio insulsa in the laboratory. Following exposure, no effects of E2 exposure were observed in females at any exposure level, however, males demonstrated significant inhibition of gamete development, regardless of dose received. In conclusion, this study supports the utility of a nonlethal gonad biopsy in the assessment of gametogenesis and reproductive condition in future studies on freshwater mussels and supports the ability of vertebrate estrogen to influence gamete development in these organisms. 2016-08-29 English text The Ohio State University / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=osu1459774776 http://rave.ohiolink.edu/etdc/view?acc_num=osu1459774776 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.