title: Relationship between reproductive success and male plasma vitellogenin concentrations in cunner, Tautogolabrus adspersus.
abstract: The gene for vitellogenin, an egg yolk protein precursor, is usually silent in male fish but can be induced by estrogen exposure. For this reason, vitellogenin production in male fish has become a widely used indicator of exposure to exogenous estrogens or estrogen mimics in the aquatic environment. The utility of this indicator to predict impacts on fish reproductive success is unclear because information on the relationship between male plasma vitellogenin and reproductive end points in male and female fish is limited. In the research reported in this article, we investigated whether the presence of male plasma vitellogenin is a reliable indicator of decreased reproductive success in mature fish. Adult and sexually mature male and female cunner (Tautogolabrus adspersus) were exposed to 17ss-estradiol, ethynylestradiol, or estrone, three steroidal estrogens that elicit the vitellogenic response. Data were gathered and pooled on egg production, egg viability, egg fertility, sperm motility, and male plasma vitellogenin concentrations. All males, including two with plasma vitellogenin levels exceeding 300 mg/mL, produced motile sperm. Neither percent fertile eggs nor percent viable eggs produced by reproductively active fish demonstrated a significant correlation with male plasma vitellogenin concentrations. Male gonadosomatic index and average daily egg production by females showed significant, but weak, negative correlation with male plasma vitellogenin concentrations. Results suggest that male plasma vitellogenin expression is not a reliable indicator of male reproductive dysfunction in adult cunner exposed to estrogens for 2-8 weeks during their reproductive season, at least in relation to capacity to produce motile sperm or fertilize eggs. Male plasma vitellogenin expression may serve as an indicator of reduced female reproductive function caused by estrogen exposure.
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, Rhode Island 02882, USA. mills.lesley@epa.gov
authors.forename: Lesley J
authors.initials: LJ
authors.lastname: Mills
authors.forename: Ruth E
authors.initials: RE
authors.lastname: Gutjahr-Gobell
authors.forename: Doranne Borsay
authors.initials: DB
authors.lastname: Horowitz
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Denslow
authors.forename: Marjorie C
authors.initials: MC
authors.lastname: Chow
authors.forename: Gerald E
authors.initials: GE
authors.lastname: Zaroogian
mesh_terms: D000818:Animals; D004703:Endocrine System / Q000187:drug effects*; D004781:Environmental Exposure; D004958:Estradiol / Q000378:metabolism / Q000633:toxicity; D004967:Estrogens / Q000378:metabolism / Q000633:toxicity*; D004970:Estrone / Q000378:metabolism / Q000633:toxicity; D005260:Female; D005298:Fertility / Q000187:drug effects; D005328:Fetal Viability / Q000187:drug effects; D005399:Fishes / Q000235:genetics*; D008297:Male; D012098:Reproduction / Q000187:drug effects*; D012722:Sewage; D013081:Sperm Motility / Q000187:drug effects; D014819:Vitellogenins / Q000097:blood*; D014873:Water Pollutants / Q000633:toxicity*; D015053:Zygote / Q000502:physiology
chemical_list: D004967:Estrogens; D012722:Sewage; D014819:Vitellogenins; D014873:Water Pollutants; D004970:Estrone; D004958:Estradiol