title: Windows of Susceptibility and Consequences of Early Life Exposures to 17β-estradiol on Medaka (Oryzias latipes) Reproductive Success.
abstract: Estrogens and estrogen mimics are commonly found in surface waters and are associated with deleterious effects in fish populations. Impaired fertility and fecundity in fish following chronic exposures to estrogens and estrogen mimics during critical windows in development are well documented. However, information regarding differential reproductive effects of exposure within defined developmental stages remains sparse. In this study, reproductive capacity was assessed in Japanese medaka (Oryzias latipes) after exposure to two concentrations of 17β-estradiol (E2β; 2 ng/L and 50 ng/L) during four distinct stages of development: gonad development, gonad differentiation, development of secondary sex characteristics (SSC) and gametogenesis. Exposure to E2β did not adversely impact survival, hatch success, growth, or genotypic ratios. In contrast, exposure to 50 ng/L E2β during SSC development altered phenotypic ratios and SSC. Exposure to both E2β treatments reduced reproductive capacity (fertility, fecundity) by 7.3-57.4% in adult medaka breeding pairs, with hindrance of SSC development resulting in the largest disruption in breeding capacity (51.6-57.4% decrease) in the high concentration. This study documents differential effects among four critical stages of development and provides insight into factors (window of exposure, exposure concentration and duration of exposure period) contributing to reproductive disruption in fish.
authors.affiliation: Department of Biological Sciences, Environmental and Molecular Toxicology Program, North Carolina State University , 850 Main Campus Drive, Raleigh, North Carolina 27606, United States.
authors.forename: Crystal S D
authors.initials: CSD
authors.lastname: Lee Pow
authors.affiliation: Department of Biological Sciences, Environmental and Molecular Toxicology Program, North Carolina State University , 850 Main Campus Drive, Raleigh, North Carolina 27606, United States.
authors.forename: Kedamawit
authors.initials: K
authors.lastname: Tilahun
authors.affiliation: Department of Biological Sciences, Environmental and Molecular Toxicology Program, North Carolina State University , 850 Main Campus Drive, Raleigh, North Carolina 27606, United States.
authors.forename: Kari
authors.initials: K
authors.lastname: Creech
authors.affiliation: Department of Population Health and Pathobiology, North Carolina State University , 1060 William Moore Drive, Raleigh, North Carolina 27607, United States.
authors.forename: J Mac
authors.initials: JM
authors.lastname: Law
authors.affiliation: Department of Applied Ecology, North Carolina State University , 127 David Clark Laboratories, Raleigh, North Carolina 27695, United States.
authors.forename: W Gregory
authors.initials: WG
authors.lastname: Cope
authors.affiliation: Department of Applied Ecology, North Carolina State University , 127 David Clark Laboratories, Raleigh, North Carolina 27695, United States.|United States Geological Survey, North Carolina Cooperative Fish and Wildlife Research Unit, Raleigh, North Carolina 27695, United States.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kwak
authors.affiliation: Department of Applied Ecology, North Carolina State University , 127 David Clark Laboratories, Raleigh, North Carolina 27695, United States.
authors.forename: James A
authors.initials: JA
authors.lastname: Rice
authors.affiliation: Department of Applied Ecology, North Carolina State University , 127 David Clark Laboratories, Raleigh, North Carolina 27695, United States.
authors.forename: D Derek
authors.initials: DD
authors.lastname: Aday
authors.affiliation: Department of Biological Sciences, Environmental and Molecular Toxicology Program, North Carolina State University , 850 Main Campus Drive, Raleigh, North Carolina 27606, United States.
authors.forename: Seth W
authors.initials: SW
authors.lastname: Kullman
mesh_terms: D000818:Animals; D004958:Estradiol / Q000494:pharmacology*; D006066:Gonads / Q000187:drug effects; D009990:Oryzias; D012098:Reproduction / Q000187:drug effects; D012733:Sex Differentiation / Q000187:drug effects
chemical_list: D004958:Estradiol