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Sample records for adult fathead minnow

  1. EFFECTS OF METHYLTOSTERONE ON AROMATASE ACTIVITY IN ADULT FATHEAD MINNOW

    EPA Science Inventory

    The effect of methyltestosterone (MT) in a fathead minnow 21-d reproduction assay was previously determined in this laboratory. It was found that methyltestosterone at 0.2 and 2 mg/L produced both estrogenic and androgenic effects. Both concentrations of methyltestosterone produc...

  2. EFFECTS OF METHYLTESTOSTERONE ON AROMATASE ACTIVITY IN ADULT FATHEAD MINNOW

    EPA Science Inventory

    The effect of methyltestosterone (MT) in a fathead minnow 21-d reproduction assay was previously determined in this laboratory. It was found that methyltestosterone at 0.2 and 2 mg/L produced both estreogenic and androgenic effects. Both concentrations of methyltestosterone produ...

  3. Kin recognition and cannibalistic behaviours by adult male fathead minnows ( Pimephales promelas)

    NASA Astrophysics Data System (ADS)

    Green, Warren W.; Mirza, Reehan S.; Pyle, Greg G.

    2008-03-01

    Parental care is an energetically demanding activity that ensures genes are efficiently passed from one generation to the next. According to evolutionary theory, the greatest energetic investment should be directed towards offspring that are most closely related to the parent. Male fathead minnows, Pimephales promelas, provide this parental investment to developing embryos but not newly hatched larvae. Therefore, selection should favour recognition of embryonic kin to ensure energetic expenditure is optimally invested. In this study, adult male fathead minnows were tested using behavioural assays, with egg cannibalism as an endpoint, to determine whether adult males could discriminate between related and unrelated embryos. Egg cannibalism was highest when adult male fathead minnows were presented with unrelated eggs and lowest when presented with eggs fertilized by the test subject (related eggs). The degree of cannibalism was also a function of breeding status. Unrelated males in breeding condition showed an intermediate response between the low cannibalism demonstrated by related males and the high cannibalism demonstrated by unrelated males in a nonbreeding condition. These results suggest that although male fathead minnows can discriminate between unrelated and related embryos, at least some component of parental investment is a simple function of breeding status.

  4. Impact of Sediment on Agrichemical Fate and Bioavailability to Adult Female Fathead Minnows: A Field Study.

    PubMed

    Zhang, Yun; Krysl, Ryan G; Ali, Jonathan M; Snow, Daniel D; Bartelt-Hunt, Shannon L; Kolok, Alan S

    2015-08-01

    Precipitation induced runoff is an important pathway for agrichemicals to enter surface water systems and expose aquatic organisms to endocrine-disrupting compounds such as pesticides and steroid hormones. The objectives of this study were to investigate the distribution of agrichemicals between dissolved and sediment-bound phases during spring pulses of agrichemicals and to evaluate the role of suspended sediment in agrichemical bioavailability to aquatic organisms. To accomplish these objectives, suspended sediment and water samples were collected every 3 days from a field site along the Elkhorn River, located at the downstream end of a heavily agricultural watershed, and were screened for 21 pesticides and 21 steroids. Adult female fathead minnows (Pimephales promelas) were exposed in field mesocosms to river water containing varying sediment loads. Changes in organism hepatic gene expression of two estrogen-responsive genes, vitellogenin (VTG) and estrogen receptor alpha (ERα), as well as the androgen receptor (AR) were analyzed during periods of both low and high river discharge. Trends in agrichemical concentrations of both the dissolved and sediment phases as a function of time show that, while sediment may act as both a source and a sink for agrichemicals following precipitation events, the overall driver for molecular defeminization in this system is direct exposure to the sediment-associated compounds. This study suggests that endocrine disrupting effects observed in organisms in turbid water could be attributed to direct exposure of contaminated sediment. PMID:26151375

  5. 17A-ETHYNYLESTRADIOL-INDUCED VITELLOGENIN GENE TRANSCRIPTION QUANTIFIED IN LIVERS OF ADULT MALES, LARVAE, AND GILLS OF FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    We have applied a method for quantifying relative levels of messenger RNA (mRNA) transcription to assess chemically-induced gene expression in fathead minnows (Pimephales promelas). Synthetic oligonucleotides designed for the fathead minnow vitellogenin gene transcription (Vg) p...

  6. Induction of vitellogenin gene expression in adult male fathead minnows for select EDCs in 48-hour exposures

    EPA Science Inventory

    Endocrine disrupting chemicals have been shown to be present in surface waters, sediments and sludge, and are known to induce vitellogenin gene liver transcripts in male fathead minnows. The purpose of our study was to establish the lowest concentrations of estrogenic chemicals ...

  7. Bold, Sedentary Fathead Minnows Have More Parasites.

    PubMed

    Pan, Tiffany; Gladen, Kelsey; Duncan, Elizabeth C; Cotner, Sehoya; Cotner, James B; McEwen, Daniel C; Wisenden, Brian D

    2016-08-01

    Parasites that rely on trophic transmission can manipulate the behavior of an intermediate host to compromise the host's antipredator competence and increase the probability of reaching the next host. Selection for parasite manipulation is diminished when there is significant risk of host death to causes other than consumption by a suitable definitive host for the parasite. Consequently, behavioral manipulation by parasites can be expected to be subtle. Ornithodiplostomum ptychocheilus (Op) is a trematode parasite that has a bird-snail-fish host life cycle. Fathead minnows are a common intermediate host of Op, where metacercariae encyst in the minnow brain. In this study, we report a link between metacercarial intensity and behavior in fathead minnows. In the field, we found that roaming distance by free-living minnows over 24 h was negatively correlated with parasite intensity. In the laboratory, we found that boldness in an open field test was positively correlated with parasite intensity. These parasite-induced behavioral changes may render infected minnows more susceptible to predators, which would serve to facilitate trophic transmission of parasites to the bird host. PMID:27093037

  8. ASSESSMENT OF A FATHEAD MINNOW REPRODUCTION ASSAY FOR IDENTIFYING ENDOCRINE-DISRUPTING CHEMICALS WITH DIVERSE MODES OF ACTION

    EPA Science Inventory

    The US EPA has developed a short-term reproduction test with the fathead minnow to identify potential endocrine disrupting chemicals (EDCs). The assay is initiated by collecting baseline spawning data from reproductively-active adult fathead minnows for 21 d, followed by a 21 d e...

  9. Bringing the fathead minnow into the genomic era

    EPA Science Inventory

    The fathead minnow is a well-established ecotoxicological model organism that has been widely used for regulatory ecotoxicity testing and research for over a half century. While a large amount of molecular information has been gathered on the fathead minnow over the years, the la...

  10. Gene prediction in the fathead minnow [Pimephales promelas] genome

    EPA Science Inventory

    The fathead minnow is a well-established model organism which has been widely used for regulatory ecotoxicity testing and research for over half century. While much information has been gathered on the organism over the years, the fathead minnow genome, a critical source of infor...

  11. Successful detection of (anti-)androgenic and aromatase inhibitors in pre-spawning adult fathead minnows (Pimephales promelas) using easily measured endpoints of sexual development.

    PubMed

    Panter, G H; Hutchinson, T H; Hurd, K S; Sherren, A; Stanley, R D; Tyler, C R

    2004-10-18

    Screening assays have been successfully developed for the detection of (anti-)oestrogenic substances in several fish species, including the fathead minnow (Pimephales promelas). Previous work suggested that pre-spawning adult fathead minnows might be an appropriate life-stage for developing a screen to detect endocrine active substances (EASs). Pre-spawning adult fathead minnows, in which their phenotypic sex could be determined, were exposed in flow-through systems to three reference substances for 21 days, at 25 degrees C. Male and female fish, held in separate tanks, were exposed to dihydrotestosterone (DHT, androgen), flutamide (anti-androgen) and fadrozole (aromatase inhibitor). Nominal (mean measured) concentrations for DHT were 10 (6.0), 32 (6.1) and 100 (8.6) microg l(-1), for flutamide, 100 (95.3), 320 (320.4) and 1000 (938.6) microg l(-1) and for fadrozole, 25 (24.8), 50 (51.7) and 100 (95.5) microg l(-1). After 14 and 21 days exposure, fish were evaluated for growth, secondary sexual characteristics (SSCs, number and prominence of nuptial tubercles), gonadosomatic index (GSI) and plasma vitellogenin (VTG) concentrations. Development of nuptial tubercles was sensitive to both DHT and flutamide exposure. Exposure to DHT significantly increased the number of nuptial tubercles (male characteristic) in both males (more abundant) and females, after 14 days. Flutamide (938.6 microg l(-1), day 21) significantly reduced nuptial tubercle number in male fish. Fadrozole significantly inhibited ovarian growth (lower GSI) and significantly induced testis growth (51.7 and 95.5 microg l(-1)), after 21 days. Plasma VTG concentrations were significantly elevated in male fish (6.1 and 8.6 microg l(-1)), but inhibited in female fish (6.0 microg l(-1)), exposed to DHT. Flutamide had no effect on plasma VTG in male fish, but significantly induced VTG in female fish, after 21 days. Fadrozole significantly inhibited VTG in females and induced VTG synthesis in males, at day 21

  12. Behavioral responses of adult male and female fathead minnows to a model estrogenic effluent and its effects on exposure regime and reproductive success.

    PubMed

    Lavelle, Candice; Sorensen, Peter W

    2011-02-01

    Laboratory studies of adult male fathead minnows have shown that when they are exposed to estrogens, they lose their ability to compete for access to females and sire young, suggesting that estrogenic effluents may reduce the genetic fitness of populations of wild fishes. However, it is unknown whether wild fish which are exposed to effluent actually compete with unexposed fishes, how long effects of estrogen exposure last, and whether females are affected by estrogens. This study addressed these issues using the fathead minnow (FHM) and effluent from the Metropolitan Wastewater Treatment Plant (MWTP) a well-studied source of environmental estrogens (EEs) in the Mississippi River. Maze tests found that adult FHMs are neither attracted nor repelled by MWTP effluent while previous studies have shown that minnows are attracted to the warmer waters which characterize effluents; it is realistic that previously unexposed fish enter MWTP effluent in the spring and then compete with exposed individuals. Competitive spawning experiments showed that male FHMs exposed to 44ng E2/l (a high but realistic level) for three weeks failed to compete with unexposed males while males exposed to 4ng E2/l outcompeted and sired more young than unexposed males (p<0.05). The effects of estrogen exposure disappeared within a week of moving fish into uncontaminated water. Female FHM reproductive output and behavior were unaffected by exposure to estrogen. Taken together, these experiments suggest that the behavior of wild fishes likely determines their exposure to EEs and that while the effects of this exposure are likely significant to populations of wild fish, they will be location specific because of factors which determine the duration and intensity of male exposure. We conclude that the role of fish behavior in endocrine disruption strongly warrants additional consideration.

  13. Behavioral responses of adult male and female fathead minnows to a model estrogenic effluent and its effects on exposure regime and reproductive success.

    PubMed

    Lavelle, Candice; Sorensen, Peter W

    2011-02-01

    Laboratory studies of adult male fathead minnows have shown that when they are exposed to estrogens, they lose their ability to compete for access to females and sire young, suggesting that estrogenic effluents may reduce the genetic fitness of populations of wild fishes. However, it is unknown whether wild fish which are exposed to effluent actually compete with unexposed fishes, how long effects of estrogen exposure last, and whether females are affected by estrogens. This study addressed these issues using the fathead minnow (FHM) and effluent from the Metropolitan Wastewater Treatment Plant (MWTP) a well-studied source of environmental estrogens (EEs) in the Mississippi River. Maze tests found that adult FHMs are neither attracted nor repelled by MWTP effluent while previous studies have shown that minnows are attracted to the warmer waters which characterize effluents; it is realistic that previously unexposed fish enter MWTP effluent in the spring and then compete with exposed individuals. Competitive spawning experiments showed that male FHMs exposed to 44ng E2/l (a high but realistic level) for three weeks failed to compete with unexposed males while males exposed to 4ng E2/l outcompeted and sired more young than unexposed males (p<0.05). The effects of estrogen exposure disappeared within a week of moving fish into uncontaminated water. Female FHM reproductive output and behavior were unaffected by exposure to estrogen. Taken together, these experiments suggest that the behavior of wild fishes likely determines their exposure to EEs and that while the effects of this exposure are likely significant to populations of wild fish, they will be location specific because of factors which determine the duration and intensity of male exposure. We conclude that the role of fish behavior in endocrine disruption strongly warrants additional consideration. PMID:21276478

  14. DEVELOPMENT OF MONOCLONAL ANTIBODIES AGAINST FATHEAD MINNOW (PIMEPHALES PROMELAS) VITELLOGENIN

    EPA Science Inventory

    We have obtained a panel of monoclonal antibodies directed against fathead minnow vitellogenin (Vtg) for use in sensitive ELISAs to quantify the response of exposure in vivo to estrogen or estrogen mimics.

  15. EXPOSURE METHOD CONSIDERATIONS FOR MEASURING VITELLOGENIN EXPRESSION IN LARVAL AND MALE FATHEAD MINNOWS (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Our laboratory has developed methods for measuring the expression of the vitellogenin (Vg) gene in larval and adult male fathead minnows. During this development we found several conditions that affect background Vg levels and we observed preconditions for the expression of this...

  16. Effects of dietary methylmercury on reproduction of fathead minnows

    USGS Publications Warehouse

    Hammerschmidt, C.R.; Sandheinrich, M.B.; Wiener, J.G.; Rada, R.G.

    2002-01-01

    We examined effects of dietary methylmercury (MeHg) on reproduction of fathead minnows (Pimephales promelas). Juvenile fish were fed one of four diets until sexual maturity (phase 1): a control diet (0.06 μg Hg g-1 dry weight) and three diets contaminated with MeHg at 0.88 (low), 4.11 (medium), and 8.46 μg Hg g-1 dry weight (high). At sexual maturity, male and female fish were paired, again fed one of the four diets, and allowed to reproduce (phase 2). To assess effects of MeHg during gametogenesis, some fish were fed diets during phase 2 that differed from those during phase 1. Spawning success of pairs fed the same diet during phases 1 and 2 was 75% for controls and 46%, 50%, and 36% for the low-, medium-, and high-MeHg treatments, respectively. Spawning success of pairs fed a contaminated diet during phase 1 and a control diet during phase 2 was 63%, 40%, and 14% for the low-, medium-, and high-MeHg treatments, respectively, whereas exposure to dietary MeHg only during phase 2 did not reduce spawning success. Dietary MeHg delayed spawning, and days to spawning was positively correlated with concentration of total mercury in the carcasses of test fish. MeHg reduced the instantaneous rate of reproduction of fish fed the same diets during phases 1 and 2. Both the gonadosomatic index and reproductive effort of female fish were inversely correlated with mercury in carcasses, whereas developmental and hatching success of embryos, 7-d survival, and 7-d growth of larvae were unrelated to mercury concentrations in parental fish or their diets. MeHg decreased reproduction of adult fathead minnows at dietary concentrations encountered by predatory fishes in aquatic systems with MeHg-contaminated food webs, implying that exposed fish populations could be adversely affected by this widespread contaminant.

  17. Chronic toxicity of ammonia to fathead minnows

    SciTech Connect

    Thurston, R.V.; Russo, R.C.; Meyn, E.L.; Zajdel, R.K.; Smith, C.E.

    1986-03-01

    Chronic effects of ammonia on the fathead minnow Pimephales promelas were studied in the laboratory in two flow-through tests, each test lasting approximately 1 year. Fish were exposed to five test concentrations over the range 0.07-0.96 mg/L un-ionized ammonia (NH/sub 3/); the mean pH of the test water was 8.0, and the mean temperature was 24.2/sup 0/C. The tests started with 3- to 5-d-old larvae that were reared to sexual maturity; progeny of these fish (F/sub 1/) were reared until they were 60 d old. The 5% probability level was chosen to indicate significance. No effects were observed on growth or survival of parental fish at 0.44 mg/L NH/sub 3/, or on egg production or viability at 0.37 mg/L, but effects on all of these were observed at 0.91 mg/L. Growth and survival of F/sub 1/ larvae were not affected at 0.36 mg/L NH/sub 3/, which was the highest concentration at which these were tested. Egg hatching success was not affected at 0.19 mg/L NH/sub 3/, but was at 0.37 mg/L. Brain lesions were common in parental fish at all stages of development at exposure concentrations of 0.21 mg/L NH/sub 3/ and higher, but not at 0.11 mg/L; no other histopathologic effects were observed at any of the test concentrations. The chronic-effects threshold concentration, based on survival, growth, and reproductive success, is estimated to be 0.27 mg/L NH/sub 3/ for the conditions of these tests. Based on histological damage, however, this concentration is estimated to be 0.15 mg/L NH/sub 3/.

  18. MICROSATELLITE DNA VARIATION IN TWO FATHEAD MINNOW (PIMEPHALES PROMELAS) STOCKS

    EPA Science Inventory

    Adverse effects on more than 2000 species of fish in the U.S. and Canada are estimated by sensitvity results of fathead minnow (Pimephales promelas) acute toxicity tests. Whether survival and susceptibility to toxicants are influenced by genetic variation is still under question...

  19. REPRODUCTIVE TOXICITY OF ANDROGENIC GROWTH PROMOTORS IN THE FATHEAD MINNOW

    EPA Science Inventory

    Reproductive Toxicity of Androgenic Growth Promoters in the Fathead Minnow. Jensen, KM*, Kahl, MD, Makynen, EA, Hornung, MW, Ankley, GT. U.S. Environmental Protection Agency, Duluth, MN. Trenbolone acetate is a synthetic steroid which is extensively used in the US as a growth pro...

  20. A METABOLOMIC APPROACH TO UNDERSTANDING ENDOCRINE DISRUPTION IN FATHEAD MINNOW

    EPA Science Inventory

    Although widely used in the study of rodent toxicity responses to assess human risk, metabolomics is now finding utility in toxicity assessments in a wide variety of other organisms including environmentally relevant small fish species such as fathead minnow (FHM) and medaka. To...

  1. COPPER TOLERANCE IN FATHEAD MINNOWS: II. MATERNAL TRANSFER

    PubMed Central

    Peake, Elizabeth B.; Locke, Jessica C.; Tierney, Laura L.; Kolok, Alan S.

    2009-01-01

    Female fathead minnows (Pimephales promelas) exposed to copper (Cu) maternally transfer Cu tolerance to their larval offspring. Larvae produced after female parents received a sublethal 5-d, 100 µg/L Cu exposure had significantly greater survivorship in potentially lethal Cu solutions than larvae produced before those females were exposed to Cu. PMID:14768887

  2. CADMIUM EXPOSURES DURING EARLY DEVELOPMENT: DO THEY LEAD TO REPRODUCTIVE IMPAIRMENT IN FATHEAD MINNOWS?

    PubMed Central

    Sellin, Marlo K.; Kolok, Alan S.

    2009-01-01

    The primary objective of this study was to determine whether cadmium (Cd) exposures during embryonic and larval development alter the reproductive performance, reproductive physiology, and sex ratio of fathead minnows (Pimephales promelas). Embryonic exposures were conducted by exposing adult female fathead minnows to 0, 25, or 100 µg/L Cd for 8 d prior to breeding. Larval exposures were conducted by exposing the larvae to waterborne Cd at 0, 12.5, 25, or 50 µg/L from 8 to 29 d posthatch (the time period associated with female sexual differentiation). Minnows from each exposure period were raised to maturity, at which time their reproductive success, secondary sexual characteristics, gonadosomatic index (GSI), plasma 11-ketotestosterone (11-KT) concentrations, and sex ratios were assessed. Results from the embryonic study reveal that Cd exposures alter the secondary sexual characteristics of male fathead minnows but do not alter reproductive performance, GSI, 11-KT concentrations, or sex ratios. Larval exposures, during the period of female sexual differentiation, significantly reduce the frequency of adult spawning and increase clutch size but do not alter fecundity, secondary sexual characteristics, GSI, or 11-KT. Subtle alterations in sex ratio were observed, indicating that larval Cd exposures may increase the proportion of females in an exposed population. PMID:17089719

  3. An inexpensive fathead minnow egg incubation and toxicant exposure system

    SciTech Connect

    Diamond, S.A.; Oris, J.T.; Guttman, S.I.

    1995-08-01

    Several methods have been developed for bulk hatching of fathead minnow eggs for laboratory and commercial culture. These methods generally involve placing whole, egg-laden breeding substrates in an aeration or water-flow device, or manually removing eggs from breeding substrates. Eggs removed from substrates are then hatched in Downing or McDonald jar hatching devices or are agitated in cylindrical vessels from which larvae are manually removed. These methods are difficult to incorporate into toxicity tests involving determination of hatching success in replicate systems. Both require either continuous water flow to individual hatching chambers or frequent static renewal, which adds to the labor of separating larvae from unhatched eggs. The authors report on an inexpensive, easily constructed system for hatching fathead minnow eggs and maintaining hatched larvae for growth and survivorship studies. Data are presented to illustrate the use of the system for toxicant exposures. This system has applications for both field and laboratory studies.

  4. I. Effects of a Dopamine Receptor Antagonist on Fathead Minnow, Pimephales promelas ,Reproduction

    EPA Science Inventory

    This study used a 21 d fathead minnow (Pimephales promelas) reproduction assay to test the hypothesis that exposure to the dopamine 2 receptor (D2R) antagonist, haloperidol, would impair fish reproduction. Additionally, a 96 h experiment with fathead minnows and zebrafish (Danio ...

  5. Proteomic Expression Patterns in Fathead Minnows Exposed to Trenbolone and Flutamide

    EPA Science Inventory

    Insights into androgen signaling in the liver of fathead minnow (Pimephales promelas) was obtained using non-gel based proteomics analysis. We exposed female fathead minnows for 48 hr through the water to a prototypical androgen (17b-trenbolone, 5 ?g/L), a prototypical anti-andr...

  6. Comparison of Transcriptomic and Proteomic Expression Patterns in Fathead Minnows Exposed to Trenbolone and Flutamide

    EPA Science Inventory

    Androgen signaling in the liver of fathead minnows (Pimephales promelas) was examined both at the transcriptome level and the proteome level. We exposed female fathead minnows for 48 hr to a prototypical androgen (17b-trenbolone, 5 ug/L), to an antiandrogen (flutamide, 50...

  7. Atrazine reduces reproduction in fathead minnow (Pimephales promelas)

    USGS Publications Warehouse

    Tillitt, D.E.; Papoulias, D.M.; Whyte, J.J.; Richter, C.A.

    2010-01-01

    Atrazine, the widely used herbicide, has shown to affect the hypothalamus-pituitary-gonad axis in certain vertebrate species, but few studies have examined reproductive effects of this chemical on fish. Our study was designed to evaluate a population endpoint (egg production) in conjunction with histological (e.g., gonad development) and biochemical (e.g., hormone production) phenotypes associated with atrazine exposure in fathead minnows. Adult virgin breeding groups of 1 male and 2 females were exposed to nominal concentrations of 0, 0.5, 5.0, and 50 ??g/L of atrazine in a flow-through diluter for 14 or 30 days. Total egg production was lower (19-39%) in all atrazine-exposed groups as compared to the controls. The decreases in cumulative egg production of atrazine treated fish were significant by 17-20 days of exposure. Reductions in egg production in atrazine treatment groups were most attributable to reduced numbers of spawning events with increased atrazine exposure concentrations. Gonad abnormalities were observed in both male and female fish of atrazine-exposed fish. Our results also indicate that atrazine reduces egg production through alteration of final maturation of oocytes. The reproductive effects observed in this study warrant further investigation and evaluation of the potential risks posed by atrazine, particularly feral populations of fish from streams in agricultural areas with high use of this herbicide. ?? 2010.

  8. Ammonia causes decreased brain monoamines in fathead minnows (Pimephales promelas)

    USGS Publications Warehouse

    Ronan, Patrick J.; Gaikowski, Mark P.; Hamilton, Steven J.; Buhl, Kevin J.; Summers, Cliff H.

    2007-01-01

    Hyperammonemia, arising from variety of disorders, leads to severe neurological dysfunction. The mechanisms of ammonia toxicity in brain are not completely understood. This study investigated the effects of ammonia on monoaminergic systems in brains of fathead minnows (Pimephales promelas). Fish serve as a good model system to investigate hyperammonemic effects on brain function since no liver manipulations are necessary to increase endogenous ammonia concentrations. Using high performance liquid chromatography with electrochemical detection, monoamines and some associated metabolites were measured from whole brain homogenate. Adult males were exposed for 48 h to six different concentrations of ammonia (0.01–2.36 mg/l unionized) which bracketed the 96-h LC50 for this species. Ammonia concentration-dependent decreases were found for the catecholamines (norepinephrine and dopamine) and the indoleamine serotonin (5-HT). After an initial increase in the 5-HT precursor 5-hydroxytryptophan it too decreased with increasing ammonia concentrations. There were also significant increases in the 5-HIAA/5-HT and DOPAC/DA ratios, often used as measures of turnover. There were no changes in epinephrine (Epi) or monoamine catabolites (DOPAC, 5-HIAA) at any ammonia concentrations tested. Results suggest that ammonia causes decreased synthesis while also causing increased release and degradation. Increased release may underlie behavioral reactions to ammonia exposure in fish. This study adds weight to a growing body of evidence demonstrating that ammonia leads to dysfunctional monoaminergic systems in brain which may underlie neurological symptoms associated with human disorders such as hepatic encephalopathy.

  9. INTRODUCTION OF THE VITELLOGENIN GENE IN EARLY LIFE STAGE FATHEAD MINNOWS AS AN EFFECTIVE EXPOSURE INDICATOR FOR ESTROGENIC COMPOUNDS

    EPA Science Inventory

    Vitellogenin (Vg) gene expression in adult male fathead minnows (FHM) has previously been used successfully to detect exposures to estrogenic compounds in aquatic systems; however, sample volume(s)required for >24h exposure durations and the logistics of sampling pose some limita...

  10. Development and validation of a 2,000-gene microarray for the fathead minnow (Pimephales promelas)

    SciTech Connect

    Larkin, Patrick; Villeneuve, Daniel L.; Knoebl, Iris; Miracle, Ann L.; Carter, Barbara J.; Liu, Li; Denslow, Nancy D.; Ankley, Gerald T.

    2007-07-01

    Gene microarrays provide the field of ecotoxicology new tools to identify mechanisms of action of chemicals and chemical mixtures. Herein we describe the development and application of a 2,000-gene oligonucleotide microarray for the fathead minnow Pimephales promelas, a species commonly used in ecological risk assessments in North America. The microarrays were developed from various cDNA and subtraction libraries that we constructed. Consistency and reproducibility of the microarrays were documented by examining multiple technical replicates. To test application of the fathead minnow microarrays, gene expression profiles of fish exposed to 17-estradiol, a well-characterized estrogen receptor (ER) agonist, were examined. For these experiments, adult male fathead minnows were exposed for 24 h to waterborne 17-estradiol (40 or 100 ng/L) in a flow-through system, and gene expression in liver samples was characterized. Seventy-one genes were identified as differentially regulated by estradiol exposure. Examination of the gene ontology designations of these genes revealed patterns consistent with estradiol’s expected mechanisms of action and also provided novel insights as to molecular effects of the estrogen. Our studies indicate the feasibility and utility of microarrays as a basis for understanding biological responses to chemical exposure in a model ecotoxicology test species.

  11. Genetic analysis of a novel nidovirus from fathead minnows

    USGS Publications Warehouse

    Batts, William N.; Goodwin, Andrew E.; Winton, James R.

    2012-01-01

    A bacilliform virus was isolated from diseased fathead minnows (Pimephales promelas). Analysis of the complete genome coding for the polyprotein (pp1ab), spike (S), membrane (M) and nucleocapsid (N) proteins revealed that the virus was most like white bream virus (WBV), another bacilliform virus isolated from white bream (Blicca bjoerkna L.) and the type species of the genus Bafinivirus within the order Nidovirales. In addition to similar gene order and size, alignment of deduced amino acid sequences of the pp1ab, M, N and S proteins of the fathead minnow nidovirus (FHMNV) with those of WBV showed 46, 44, 39 and 15 % identities, respectively. Phylogenetic analysis using the conserved helicase domain of the replicase showed FHMNV was distinct from WBV, yet the closest relative identified to date. Thus, FHMNV appears to represent a second species in the genus Bafinivirus. A PCR assay was developed for the identification of future FHMNV-like isolates.

  12. Propiconazole inhibits steroidogenesis and reproduction in the fathead minnow (Pimephales promelas)

    EPA Science Inventory

    This study assessed effects of the conazole-fungicide propiconazole on endocrine function and reproductive success of the fathead minnow, using an experimental approach based on previously defined adverse outcome pathways (AOPs) for chemicals that inhibit steroidogenesis in fish...

  13. Inference of a Transcriptional Network Involved in Chemical Inhibition of Estrogen Synthesis in Fathead Minnow

    EPA Science Inventory

    A variety of chemicals in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. We examined the responses of female fathead minnows (Pimephales promelas) to a model aromatase inhibitor, fadrozole, using transcriptional network inferen...

  14. Influence of Ovarian Stage on Transcript Profiles in Fathead Minnow (Pimephales promelas) Ovary Tissue

    EPA Science Inventory

    Small fish species with an asynchronous pattern of gonad development and reproduction are commonly used test organisms in aquatic ecotoxicology and more recently in ecotoxicogenomics. This study applies coordinated histological examination and fathead minnow oligonucleotide micr...

  15. Effects of antiandrogen flutamide on steroidogenesis and gene expression in female fathead minnow ovary

    EPA Science Inventory

    Mechanisms underlying reproductive impacts of antiandrogens in fish are not well-characterized and effective biomarkers of antiandrogen exposure are lacking. This work sought to identify genes and pathways affected by antiandrogen exposure in the fathead minnow (Pimephales promel...

  16. HERITABLE REPRODUCTIVE EFFECTS OF BENZO[A]PYRENE ON THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Environmental toxicologists rarely investigate multigeneration effects of aquatic contaminants. In this study we investigated the survivorship of fathead minnow larvae two generations removed from an exposure to the potent mutagen benzo [a] pyrene. The F2 broods with grandparenta...

  17. A Quantative Adverse Outcome Pathway Linking Aromatase Inhibition in Fathead Minnows with Population Dynamics

    EPA Science Inventory

    A Quantitative Adverse Outcome Pathway Linking Aromatase Inhibition in Fathead Minnows with Population DynamicsAn adverse outcome pathway (AOP) is a qualitative description linking a molecular initiating event (MIE) with measureable key events leading to an adverse outcome (AO). ...

  18. Effects of a Short-term Exposure to the Fungicide Prochloraz on Endocrine Function and Gene Expression in Female Fathead Minnows (Pimephales promelas)

    EPA Science Inventory

    Prochloraz is a fungicide known to cause endocrine disruption through effects on the hypothalamic-pituitary-gonadal (HPG) axis. To determine the short-term impacts of prochloraz on gene expression and steroid production, adult female fathead minnows (Pimephales promelas) were exp...

  19. EFFECTS OF EUTROPHICATION ON VITELLOGENIN GENE EXPRESSION IN MALE FATHEAD MINNOWS (PIMEPHALES PROMELAS) EXPOSED TO 17A-ETHYNYLESTRADIOL IN FIELD MESOCOSMS

    EPA Science Inventory

    This study evaluated the effect of aquatic secondary nutrient supply levels (nitrogen and phosphorus) on the subcellular response of adult male fathead minnows (Pimephales promelas) exposed to a single nominal concentration of 17a-ethynylestradiol (EE2), a potent synthetic estrog...

  20. Chronic effects of acetone on the fathead minnow (Pimephales promelas) during early life-stage development

    SciTech Connect

    Mank, M.; Swigert, J.

    1995-12-31

    A 28-day post-hatch early life-stage development toxicity test was conducted to determine the chronic effects of acetone on the fathead minnow (Pimephales promelas). In this study, less than 24-hour old fathead minnow embryos were exposed to 0.25, 0.50, 1.0, 2.0, and 4.0 mL acetone/L and a negative control for a 4-day pre-hatch period and 28 days following hatch. During the pre-hatch period, no adverse effects on embryo survival or hatching success were observed in any of the treatment groups tested when compared to the negative control. From completion of matching to test termination, fathead minnows exposed to 4.0 mL acetone/L, experienced reduced survival, a statistically significant reduction in growth and impairment of critical behavioral functions when compared to the negative control group. Growth of fathead minnows exposed to 2.0 mL acetone/L also experienced a statistically significant effect upon growth when compared to the negative control, however, survival and behavior were not affected during the post-hatch period. Survival, growth, and behavior of fathead minnows exposed to 0.25, 0.50, and 1.0 mL acetone/L from hatching to test termination was comparable to the control group. The no observed effect concentration (NOEC) for fathead minnows exposed to acetone during early life-stage development was 1.0 mL acetone/L, and the lowest observed effect concentration (LOEC) was 2.0 mL acetone/L. The maximum acceptable toxicant concentration (MATC) was calculated to be 1.4 mL acetone/L.

  1. Histopathology of fathead minnow (Pimephales promelas) exposed to hydroxylated fullerenes.

    PubMed

    Jovanović, Boris; Whitley, Elizabeth M; Palić, Dušan

    2014-11-01

    Hydroxylated fullerenes are reported to be very strong antioxidants, acting to quench reactive oxygen species, thus having strong potential for important and widespread applications in innovative therapies for a variety of disease processes. However, their potential for toxicological side effects is still largely controversial and unknown. Effects of hydroxylated fullerenes C60(OH)24 on the fathead minnow (Pimephales promelas) were investigated microscopically after a 72-hour (acute) exposure by intraperitoneal injection of 20 ppm of hydroxylated fullerenes per gram of body mass. Cumulative, semi-quantitative histopathologic evaluation of brain, liver, anterior kidney, posterior kidney, skin, coelom, gills and the vestibuloauditory system revealed significant differences between control and hydroxylated fullerene-treated fish. Fullerene-treated fish had much higher cumulative histopathology scores. Histopathologic changes included loss of cellularity in the interstitium of the kidney, a primary site of haematopoiesis in fish, and loss of intracytoplasmic glycogen in liver. In the coelom, variable numbers of leukocytes, including many macrophages and fewer heterophils and rodlet cells, were admixed with the nanomaterial. These findings raise concern about in vivo administration of hydroxylated fullerenes in experimental drugs and procedures in human medicine, and should be investigated in more detail.

  2. Effects of atrazine on fathead minnow in a short-term reproduction assay.

    PubMed

    Bringolf, Robert B; Belden, Jason B; Summerfelt, Robert C

    2004-04-01

    Atrazine is the most extensively used herbicide in the United States. Part-per-million concentrations of atrazine have been reported in agricultural runoff. It is detectable in surface waters and precipitation throughout the year, and it has been found in groundwater sources of drinking water. Recent studies indicate that atrazine may be a potent endocrine-disrupting compound in frogs exposed to part-per-billion (microg/L) concentrations. For these reasons, the effects of atrazine (5 and 50 microg/L) on several endpoints related to reproductive fitness were examined in fathead minnows (Pimephales promelas) in a 21-d static exposure. Estradiol (0.5 microg/L) was included as a positive-control treatment. Endpoints examined in adult fish during and after the exposures included survival, egg production, number of spawns, eggs/spawn, relative gonad weight, gonad histology, number of nuptial tubercles, and plasma vitellogenin concentration. Eggs produced during the exposures were hatched and reared in control water. The percentages of embryos fertilized and hatched as well as larval survival were evaluated. Decreasing trends were observed in relative testis weight, testis maturity, and percentage embryo fertilization. These trends suggest that further investigation is warranted, but the differences in these and other endpoints were not statistically significant in the atrazine-exposed fish. Nearly all endpoints concerning fish exposed to estradiol were significantly different from atrazine-exposed fish and control fish. These results suggest that atrazine did not have strong estrogenic effects in adult fathead minnows and did not cause overt reproductive toxicity at environmentally relevant concentrations.

  3. Dynamic nature of alterations in the endocrine system of fathead minnows exposed to the fungicide prochloraz.

    PubMed

    Ankley, Gerald T; Bencic, David C; Cavallin, Jenna E; Jensen, Kathleen M; Kahl, Michael D; Makynen, Elizabeth A; Martinovic, Dalma; Mueller, Nathaniel D; Wehmas, Leah C; Villeneuve, Daniel L

    2009-12-01

    The vertebrate hypothalamic-pituitary-gonadal (HPG) axis is controlled through various feedback mechanisms that maintain a dynamic homeostasis in the face of changing environmental conditions, including exposure to chemicals. We assessed the effects of prochloraz on HPG axis function in adult fathead minnows (Pimephales promelas) at multiple sampling times during 8-day exposure and 8-day depuration/recovery phases. Consistent with one mechanism of action of prochloraz, inhibition of cytochrome P450 (CYP) 19 aromatase activity, the fungicide depressed ex vivo ovarian production and plasma concentrations of 17beta-estradiol (E2) in female fish. At a prochloraz water concentration of 30 microg/l, inhibitory effects on E2 production were transitory and did not persist during the 8-day exposure phase. At 300 microg/l prochloraz, inhibition of E2 production was evident throughout the 8-day exposure but steroid titers recovered within 1 day of cessation of exposure. Compensation or recovery of steroid production in prochloraz-exposed females was accompanied by upregulation of several ovarian genes associated with steroidogenesis, including cyp19a1a, cyp17 (hydroxylase/lyase), cyp11a (cholesterol side-chain cleavage), and follicle-stimulating hormone receptor. In male fathead minnows, the 8-day prochloraz exposure decreased testosterone (T) production, possibly through inhibition of CYP17. However, as for E2 in females, ex vivo testicular production and plasma concentrations of T recovered within 1 day of stopping exposure. Steroidogenic genes upregulated in testis included cyp17 and cyp11a. These studies demonstrate the adaptability of the HPG axis to chemical stress and highlight the need to consider the dynamic nature of the system when developing approaches to assess potential risks of endocrine-active chemicals.

  4. A NEW APPROACH FOR THE CULTURE OF FATHEAD MINNOWS, PIMEPHALES PROMELAS

    EPA Science Inventory

    Fathead minnows (Pimphales promelas) are routinely cultured for use in aquatic toxicology studies. Most culture systems consist of a series of 4 to 30 individual tanks with 16 - 18 fish (2 males and 14-16 females) in each tank. The new mass culture system consists of six 50 gal...

  5. Adaptive Responses to Prochloraz Exposure in the Hypothalamic-Pituitary Gonadal Axis of Fathead Minnows

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict doseresponse and time-course ...

  6. COMPARISON OF QPCR METHODS FOR THE DETECTION OF VITELLOGENIN EXPRESSION IN FATHEAD MINNOWS

    EPA Science Inventory

    Male fathead minnows (FHM) normally express little if any of the egg yolk precursor protein vitellogenin (Vg). However, when exposed to estrogenic compounds such as 17a-ethynylestradiol (EE2), transcriptional levels of Vg rise dramatically and result in decreased fecundity and i...

  7. A SHORT-TERM REPRODUCTION TEST WITH THE FATHEAD MINNOW PIMEPHALES PROMELAS: II. METHOD EVALUATION

    EPA Science Inventory

    The objective of these studies was to evaluate a short-term test that assesses alterations in reproduction and endocrine function in the fathead minnow (Pimephales promelas) as a basis for identifying endocrine-disrupting chemicals. Methoxychlor and methyltestosterone were select...

  8. ASPECTS OF BASIC REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    The fathead minnow has been proposed as a model species for assessing the adverse effects of endocrine-disrupting chemicals (EDCs) on reproduction and development. The purpose of these studies was to develop baseline reproductive biology and endocrinology data for this species to...

  9. Direct Effects, Compensation, and Recovery in Female Fathead Minnows Exposed to the Aromatase Inhibitor Fadrozole

    EPA Science Inventory

    A variety of chemicals present in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. The objective of this study was to provide a detailed characterization of the molecular and biochemical responses of female fathead minnows to a m...

  10. Environmental hormones and their impacts on sex differentiation in fathead minnows

    EPA Science Inventory

    Runoff from lands fertilized with animal manure from concentrated animal feeding operations (CAFOs) is a source of hormones to surface water. To test the hypothesis that juvenile fathead minnows exposed to sex steroids singly and in a “typical” CAFO mixture while undergoing sex...

  11. Sex-specific gonadal and gene expression changes throughout development in fathead minnow

    EPA Science Inventory

    Although fathead minnows (Pimephales promelas) are commonly used as a model fish in endocrine disruption studies, none have characterized sex-specific baseline expression of genes involved in sex differentiation during development in this species. Using a sex-linked DNA marker t...

  12. A New Approach for the Laboratory Culture of the Fathead Minnow, Pimephales promelas

    EPA Science Inventory

    Fathead minnows (Pimphales promelas) are routinely cultured for use in aquatic toxicology studies. Most culture systems consist of a series of 4 to 30 individual tanks with a varied number of breeding pairs in each tank. A new mass culture system described here consists of six ...

  13. IN VIVO CONFIRMATION OF THE ANTI-ANDROGENIC NATURE OF FLUTAMIDE IN THE FATHEAD MINNOW

    EPA Science Inventory

    A short-term reproduction assay with the fathead minnow has been developed to detect chemicals with the potential to disrupt reproductive endocrine function controlled by estrogen- and androgen-mediated pathways. As part of characterizing the assay, tests have been conducted wit...

  14. Sequencing and De novo Draft Assemblies of the Fathead Minnow (Pimphales promelas)Reference Genome

    EPA Science Inventory

    This study was undertaken to develop genome-scale resources for the fathead minnow (Pimphales promelas) an important model organism widely used in both aquatic ecotoxicology research and in regulatory toxicity testing. We report on the first sequencing and two draft assemblies fo...

  15. Gene prediction in the fathead minnow [Pimephales promelas] genome-presentation

    EPA Science Inventory

    The fathead minnow is a well-established ecotoxicological model organism, having been widely used for regulatory ecotoxicity testing and research for over a half century. While a large amount of molecular information has been gathered on the organism over the years, to date, the ...

  16. Direct Effects, Compensation, and Recovery in Female Fathead Minnows Exposed to a Model Aromatase Inhibitor

    EPA Science Inventory

    The paper reports on the effects of a model aromatase inhibitor, fadrozole, on molecular and biochemical endpoints within the fathead minnow reproductive axis. Unlike previous studies, this work incorporated extensive time-course characterization over the course of an 8 d exposu...

  17. Acute aquatic toxicity of nine alcohol ethoxylate surfactants to fathead minnow and Daphnia magna

    SciTech Connect

    Wong, D.C.L.; Dorn, P.B.; Chai, E.Y.

    1995-12-31

    The aquatic toxicity of nine commercial-grade alcohol ethoxylate surfactants was studied in acute exposures to fathead minnow (Pimephales promelas) and Daphnia magna. All studies were conducted in accordance with USEPA TSCA Good Laboratory Practice Standards. Mean measured surfactant concentrations in exposure solutions showed good agreement with nominal concentrations for both fathead minnow and daphnid tests. Surfactant recoveries ranged from 59 to 97% and 67 to 106% in the fathead minnow and daphnid solutions, respectively. The response of both species to the surfactants was generally similar with the daphnids being slightly more sensitive to a few surfactants. Surfactant toxicity tended to increase with increasing alkyl chain lengths. The effect of low average EO groups on increased surfactant toxicity was more evident in the daphnid exposures. Quantitative structure-activity relationship (QSAR) models were developed form the data which relates surfactant structure to toxicity. The models predict increasing toxicity with decreasing EO number and increasing alkyl chain length. The models also indicate that alkyl chain length has a greater effect on toxicity than EO groups. Further, the models indicate that both species did not differ markedly in their sensitivity to alkyl chain length effects, while the number of EO groups had a stronger effect on daphnids than fathead minnow. Good agreement was found between QSAR model-predicted toxicity and reported toxicity values from the literature for several surfactants previously studied.

  18. DEVELOPMENT OF A FATHEAD MINNOW MODEL FOR EVALUATING EXPOSURE OF FISH TO GENOTOXIC SUBSTANCES

    EPA Science Inventory

    The fathead minnow (FHM) is widely used as a standard test species for acute and chronic toxicity testing of contaminants, effluents, and receiving waters. Because of its widespread distribution throughout North America, this species also has application in monitoring studies and...

  19. EFFECTS OF THE HORMONAL GROWTH SUPPLEMENT TRENBOLONE ON REPRODUCTIVE ENDOCRINOLOGY OF THE FATHEAD MINNOW

    EPA Science Inventory

    As part of an ongoing effort to develop and validate a fathead minnow (Pimephales promelas) assay to detect chemicals that affect processes controlled by estrogens and androgens, we determined the effects of trenbolone on reproductive endocrinology of the fish. Trenbolone is a sy...

  20. Male Fathead Minnow Urine-Based Metabolomics for Assessing Impacts of Chemical Stressors

    EPA Science Inventory

    We have developed the potential for profiling metabolites in urine from male fathead minnows (Pimephales promelas) to assess chemical exposures, using nuclear magnetic resonance (NMR) spectroscopy. Both one dimensional (1D) and two dimensional (2D) NMR spectroscopy was us...

  1. Social Status Modulates Gene Expression and Metabolite Profiles in the Fathead Minnow Males

    EPA Science Inventory

    The fathead minnow (FHM) is a valuable small fish model for genomic research in ecotoxicology. Our recent studies have successfully used genomic and metabolomic analyses to evaluate responses to endocrine disrupting compounds (EDCs) in urine of the FHM, but these results indicate...

  2. Effects of 2,3,7,8-TCDD on the larvae of fathead minnows (Pimephales promelas)

    SciTech Connect

    Olivieri, C.E.; Cooper, K.R.

    1994-12-31

    This study evaluated the sensitivity of the fathead minnow larvae to 2,3,7,8-TCDD. There are no reported studies that have examined 2,3,7,8-TCDD toxic effects on fathead minnow larvae (0.0017--0.0094 g). One month old fathead minnow larvae were exposed to varying concentrations of [H{sup 3}]2,3,7,8-TCDD for 24h, and then were transferred into clean water. The no-treatment, acetone-control and 2,3,7,8-TCDD exposed larvae were observed for at least 32 days after exposure. Mortality, growth and appearance of a wasting-type syndrome were noted. The tissue dose were based on larvae wet weight. One hundred percent mortality was observed at a tissue dose of 163 ng/g at 32 days. The wasting-type syndrome appeared at day 7 after the 2,3,7,8-TCDD exposure. Statistically significant differences in growth (total length and weight) were observed at tissue doses as low as 20 ng/g. The wasting-type syndrome was observed in all fish by day 20. The 2,3,7,8-TCDD tissue level showing this effect was 44 ng/g. These results suggested that the fathead minnow larvae are more sensitive than the Japanese medaka larvae, and not as sensitive as the lake trout.

  3. DEVELOPMENT AND VALIDATION OF A 2,000 GENE MICROARRAY FOR THE FATHEAD MINNOW, PIMEPHALES PROMELAS

    EPA Science Inventory

    The development of the gene microarray has provided the field of ecotoxicology a new tool to identify modes of action (MOA) of chemicals and chemical mixtures. Herein we describe the development and application of a 2,000 gene oligonucleotide microarray for the fathead minnow (P...

  4. Characterization of Ontogenetic Changes in Gene Expression in the Fathead Minnow Pimephales promelas

    EPA Science Inventory

    The fathead minnow Pimephales promelas is often used for ecotoxicological studies in the US and elsewhere. Recently, researchers have begun looking at changes in gene expression in this species after contaminant exposure, mostly as a way to unravel novel mechanisms of act...

  5. VITELLOGENIN ELISA FOR FATHEAD MINNOWS (PIMEPHALES PROMELAS) USING A COMPLETELY HOMOLOGOUS ASSAY SYSTEMS

    EPA Science Inventory

    The indication of vitellogenin in fish has been used as a biomarker for estrogen-receptor mediated gene induction pathways resulting from exposure to environmental estrogens. Pimephales promelas (fathead minnows) have been selected as one of the test models to investigate reprodu...

  6. COMPARISON OF ELISAS FOR DETECTING VITELLOGENIN IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Measurement of vitellogenin (VTG) concentrations in the fathead minnow is currently being evaluated and considered for screening of endocrine active substances. One of the proposed methods, an enzyme-linked immunosorbent assay (ELISA) based on VTG from carp, was recently evaluate...

  7. Lead effects on the predictability of reproductive behavior in fathead minnows (Pimephales promelas): A mathematical model

    SciTech Connect

    Alados, C.L.; Weber, D.N.

    1999-10-01

    Lead (Pb) has been shown to affect the behavior of a wide variety of vertebrates, including fish, amphibians, and mammals. This article re-examines previous data on the effect of short-term, sublethal levels of waterborne Pb on the reproductive behavior of fathead minnows (Pimephales promelas). Previous research has found that Pb decreased the time spent in displaying specific reproductive behaviors in male minnows. Because each activity performed within a sequence depends upon previous parts of the sequence, the reproductive behavior of fish is not randomly distributed but is presented as a long-range self-similar correlation. By treating these data as a fractal dimension, it is now possible to determine changes in the long-term correlation of different behavioral sequences involved in nest maintenance owing to Pb exposure, both before and after adult males attain reproductive maturity. The authors hypothesized that the scaling exponent of this fluctuation varies in relation with environmental contaminants. Known Pb-induced changes in hormonal activity may account for changes in observed reproductive and nest maintenance behaviors. Pb-exposed fish exhibited higher levels of predictability in their behavioral sequences, i.e., they demonstrated an increase in the scaling parameter of the fluctuation {alpha}. However, if Pb was introduced after sexual maturity was observed, there was no significant difference in the scaling component {alpha}. Thus, the use of fractal dimension may provide a useful tool to analyze the effects of environmental contaminants and other stresses.

  8. Phytoestrogens in the environment, II: microbiological degradation of phytoestrogens and the response of fathead minnows to degradate exposure.

    PubMed

    Kelly, Megan M; Fleischhacker, Nathan T; Rearick, Daniel C; Arnold, William A; Schoenfuss, Heiko L; Novak, Paige J

    2014-03-01

    Phytoestrogens are endocrine active compounds derived from plants, including the isoflavones genistein and daidzein, and their methylated derivatives biochanin A and formononetin. These compounds have been detected at the µg/L level in the effluents of plant-processing industries and municipal treatment plants and at the ng/L level in surface waters worldwide. The present study assessed the persistence of genistein and daidzein in natural aquatic systems, specifically riverine samples. Initial concentration, temperature, sample location, and time of sample collection varied. Genistein and daidzein were found to be readily biodegradable at all tested concentrations, at both 10 °C and 20 °C, in samples collected during different seasons, and in samples from 3 different rivers. In addition, organismal responses in larval and sexually mature fathead minnows (Pimephales promelas) were quantified following exposure to microbiologically degraded phytoestrogens (genistein, daidzein, and formononetin). Products of the microbiological degradation of parent phytoestrogens did not affect larval survival, growth, or predator avoidance. Female adult fathead minnows exposed to these degradation products produced significantly fewer eggs than those exposed to a control, but no other morphological, physiological, or behavioral changes were observed with male or female minnows. The present research suggests that although phytoestrogens are not likely to persist in aquatic systems, they may pseudo-persist if discharges are continuous; in addition, caution should be exercised with respect to high-concentration effluents because of the potentially antiestrogenic effects of phytoestrogen degradates.

  9. Transcription of Key Genes Regulating Gonadal Steroidogenesis in Control and Ketoconazole- or Vinclozolin-exposed Fathead Minnows

    EPA Science Inventory

    This paper provides the first report on the effects of two endocrine-active fungicides, ketoconazole and vinclozolin, on the expression of steroidogenesis-related genes in the testis of male fathead minnows.

  10. Computational Modeling to Evaluate Alternative Hypotheses for the Linkage of Aromatase Inhibition to Vitellogenin Levels in Fathead Minnows

    EPA Science Inventory

    Aromatase converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis of the glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Fathead minnows were exposed to the aromatase in...

  11. EVALUATION OF A WASTEWATER DISCHARGE USING VITELLOGENIN GENE EXPRESSION AND PLASMA PROTEIN LEVELS IN MALE FATHEAD MINNOWS

    EPA Science Inventory

    Liver vitellogenin gene expression and plasma vitellogenin protein presence, indicators of exposure of fish to estrogens, were measured in male fathead minnows (Pimephales promelas) caged at two locations in a constructed wetland below a sewage treatment plant effluent outfall in...

  12. What is Normal? A Characterization of the Values and Variabilty in Reproductive Endpoints of the Fathead Minnow, Pimephales promelas

    EPA Science Inventory

    Jensen et al. investigated aspects of the normal reproductive biology of the fathead minnow (FHM, P. promelas), and subsequent studies have generated a large amount of additional reproductive data for endpoints such as plasma steroid hormone and vitellogenin concentrations, spa...

  13. Altered Gene Expression in the Brain and Liver of Female Fathead Minnows Pimephales promelas Rafinesque Exposed to Fadrozole

    EPA Science Inventory

    Overall, results of this study demonstrate the utility of high density oligonucleotide microarrays for unsupervised, discovery-driven, ecotoxicogenomics research with the fathead minnow and helped inform the subsequent development of a 22,000 gene microarray for the species.

  14. Fathead Minnow Steroidogenesis: In Silico Analyses Reveals Tradeoffs Between Nominal Target Efficacy and Robustness to Cross-talk

    EPA Science Inventory

    This paper presents the formulation and evaluation of a mechanistic mathematical model of fathead minnow ovarian steroidogenesis. The model presented in the present study was adpated from other models developed as part of an integrated, multi-disciplinary computational toxicolog...

  15. GENE EXPRESSION PROFILING PROVIDES A SENSITIVE MEASURE OF EXPOSURE TO 17-A ETHINYLESTRADIOL IN THE FATHEAD MINNOW, PIMEPHALES PROMELAS

    EPA Science Inventory

    The freshwater fish, the fathead minnow (Pimephales promelas) represents an outstanding biological indicator response model organism based on its ubiquitous North American distribution and extensive use in acute and chronic testing of contaminants, effluents and receiving waters....

  16. Early life stage (ELS) toxicity of sucralose to fathead minnows, Pimephales promelas.

    PubMed

    Stoddard, K I; Huggett, D B

    2014-10-01

    Sucralose, an intense artificial sweetener, has been detected in wastewater and surface waters at concentrations ranging from ng/L to low µg/L. Although over a hundred studies have been conducted to evaluate the safety of sucralose for human consumption, few studies have focused on the chronic ecotoxicological effects of this compound in fish. As a remedy to this data gap, an early-life stage toxicity test was conducted to assess the effects of sucralose on hatching, survival, and growth of fathead minnows (Pimephales promelas). Hatching, survival, and growth were unaffected by 98 mg/L of sucralose. The Lowest-Observed-Effect Concentration (LOEC) and the No-Observed-Effect Concentration (NOEC) for fathead minnows determined by this study are >98 and 98 mg/L, respectively. The results from this study suggest that the concentrations of sucralose detected in the environment are well below those required to cause adverse effects to developing aquatic organisms. PMID:25120258

  17. Sequencing and de novo draft assemblies of a fathead minnow (Pimephales promelas) reference genome.

    PubMed

    Burns, Frank R; Cogburn, Amarin L; Ankley, Gerald T; Villeneuve, Daniel L; Waits, Eric; Chang, Yun-Juan; Llaca, Victor; Deschamps, Stephane D; Jackson, Raymond E; Hoke, Robert Alan

    2016-01-01

    The present study was undertaken to provide the foundation for development of genome-scale resources for the fathead minnow (Pimephales promelas), an important model organism widely used in both aquatic toxicology research and regulatory testing. The authors report on the first sequencing and 2 draft assemblies for the reference genome of this species. Approximately 120× sequence coverage was achieved via Illumina sequencing of a combination of paired-end, mate-pair, and fosmid libraries. Evaluation and comparison of these assemblies demonstrate that they are of sufficient quality to be useful for genome-enabled studies, with 418 of 458 (91%) conserved eukaryotic genes mapping to at least 1 of the assemblies. In addition to its immediate utility, the present work provides a strong foundation on which to build further refinements of a reference genome for the fathead minnow.

  18. Heritable reproductive effects of benzo[a]pyrene on the fathead minnow (Pimephales promelas)

    SciTech Connect

    White, P.A.; Robitaille, S.; Rasmussen, J.B.

    1999-08-01

    Environmental toxicologists rarely investigate multigeneration effects of aquatic contaminants. In this study the authors investigated the survivorship of fathead minnow larvae two generations removed from an exposure to the potent mutagen benzo[a]pyrene. The F2 broods with a grandparental exposure history showed a marked decrease in survival. In the highest-exposure group, reproductive capacity and larval survivorship were significantly lower than the solvent control.

  19. Phytoestrogens in the environment, I: occurrence and exposure effects on fathead minnows.

    PubMed

    Rearick, Daniel C; Fleischhacker, Nathan T; Kelly, Megan M; Arnold, William A; Novak, Paige J; Schoenfuss, Heiko L

    2014-03-01

    Naturally occurring phytoestrogens may mimic biogenic estrogens and modulate endocrine action in vertebrates. Little is known, however, about their temporal and spatial variability in the environment and the biological effects associated with exposures. The present study assessed the environmental presence of phytoestrogens in human-impacted and relatively pristine areas. The response in larval and sexually mature fathead minnows to environmentally relevant concentrations of 3 common phytoestrogens (genistein, daidzein, and formononetin), both singly and in mixture, was also quantified. Phytoestrogens were only present in the human-impacted surface waters. When detected, mean concentrations were low (± standard deviation) in an urban lake: 1.4 ± 0.5 ng/L, 1.6 ± 0.7 ng/L, and 1.1 ± 0.2 ng/L for genistein, daidzein, and formononetin, respectively, and in treated wastewater effluent: 1.6 ± 0.4 ng/L, 1.8 ± 1.3 ng/L, and 2.0 ng/L. Biochanin A was detected twice, whereas zearalenone and coumestrol were never detected. No clear temporal trends of aqueous phytoestrogen concentration were evident. Larval survival was significantly reduced in genistein, formononetin, and mixture treatments, whereas adult male fish only exhibited subtle changes to their anatomy, physiology, and behavior. Daidzein-exposed adult females produced greater quantities of eggs. The present study indicates that genistein, daidzein, and formononetin are likely attenuated rapidly and are unlikely to cause widespread ecological harm in the absence of other stressors.

  20. Toxicity of photoactivated PAHs to early lifestages of endangered fish and fathead minnows

    SciTech Connect

    Kemble, N.E.; Mount, D.R.; Echols, K.R.; Zumwalt, D.C.

    1995-12-31

    The San Juan River Basin, located in the Four Corners area of the southwestern US, contains some of the largest oil and gas reserves in the US. The basin is also critical habitat for several native fishes, including the endangered Colorado squawfish and razorback sucker. Proposed expansion of oil and gas development in the San Juan basin has sparked concerns that potential increases in PAH loading may jeopardize these and other native fishes. Previous acute exposures of juvenile fish to fluoranthene, anthracene, pyrene, and chrysene showed that LC{sub 50} values for the two endangered species were within a factor of 2 of those for fathead minnows, However, subsequent experiments showed that fathead minnow fry were far more sensitive than juvenile fish. In response to this finding, additional exposures to fluoranthene and UV were conducted using early life stages of the endangered fish and fathead minnows. These experiments confirmed that fry were several-fold more sensitive to photoactivated PAH toxicity than were juvenile fish; in addition, the authors found that fry responded much more quickly to PAH/UV exposure. These findings, coupled with other environmental factors, suggest that early life stages of fish may be particularly susceptible to photoactivated PAH toxicity in the field.

  1. Effects of environmental exposure to diazepam on the reproductive behavior of fathead minnow, Pimephales promelas.

    PubMed

    Lorenzi, Varenka; Choe, Ree; Schlenk, Daniel

    2016-05-01

    Pharmaceutical drugs are continuously discharged into the aquatic environment primarily through wastewater discharge; therefore, their possible effects on wildlife is a reason of concern. Diazepam is a widely prescribed benzodiazepine drug used to treat insomnia and anxiety disorders, and it has been found in wastewater effluents worldwide. The present study tested the effects of diazepam on fecundity and the reproductive behavior of the fathead minnow, Pimephales promelas, a fish that exhibits male parental care. Sexually mature fathead minnows were housed at a ratio of one male and two females per tank and exposed to nominal (measured) concentrations of 0, 0.1 (0.14 ± 0.06), 1.0 (1.04 ± 0.15), 10 (13.4 ± 1.5) µg L(-1) for 21 days. Fish receiving the low diazepam treatment had significantly larger clutches than fish receiving the highest concentration but neither were different from controls. Diazepam exposure was not associated with a significant change in fertilization rate, hatchability or time to hatch, but a trend toward a higher number of eggs/day was observed in fish exposed to the low diazepam concentration relative to those exposed to the medium concentration. There were no significant differences in any of the behaviors analyzed when responses were averaged over time. The results showed that exposure to diazepam at concentrations as high as 13 µg L(-1) did not significantly impact the reproductive behavior of fathead minnow.

  2. Antidepressants at environmentally relevant concentrations affect predator avoidance behavior of larval fathead minnows (Pimephales promelas)

    USGS Publications Warehouse

    Painter, M.M.; Buerkley, M.A.; Julius, M.L.; Vajda, A.M.; Norris, D.O.; Barber, L.B.; Furlong, E.T.; Schultz, M.M.; Schoenfuss, H.L.

    2009-01-01

    The effects of embryonic and larval exposure to environmentally relevant (ng/L) concentrations of common antidepressants, fluoxetine, sertraline, venlafaxine, and bupropion (singularly and in mixture) on C-start escape behavior were evaluated in fathead minnows (Pimephales promelas). Embryos (postfertilization until hatching) were exposed for 5 d and, after hatching, were allowed to grow in control well water until 12 d old. Similarly, posthatch fathead minnows were exposed for 12 d to these compounds. High-speed (1,000 frames/s) video recordings of escape behavior were collected and transferred to National Institutes of Health Image for frame-by-frame analysis of latency periods, escape velocities, and total escape response (combination of latency period and escape velocity). When tested 12 d posthatch, fluoxetine and venlafaxine adversely affected C-start performance of larvae exposed as embryos. Conversely, larvae exposed for 12 d posthatch did not exhibit altered escape responses when exposed to fluoxetine but were affected by venlafaxine and bupropion exposure. Mixtures of these four antidepressant pharmaceuticals slowed predator avoidance behaviors in larval fathead minnows regardless of the exposure window. The direct impact of reduced C-start performance on survival and, ultimately, reproductive fitness provides an avenue to assess the ecological relevance of exposure in an assay of relatively short duration. ?? 2009 SETAC.

  3. Antidepressants at environmentally relevant concentrations affect predator avoidance behavior of larval fathead minnows (Pimephales promelas).

    USGS Publications Warehouse

    Furlong, Edward T.; Barber, Larry B.; Meghan R. McGee,; Megan A. Buerkley,; Matthew L. Julius,; Vajda, Alan M.; Heiko L. Schoenfuss,; Schultz, Melissa M.; Norris, David O.

    2009-01-01

    The effects of embryonic and larval exposure to environmentally relevant (ng/L) concentrations of common antidepressants, fluoxetine, sertraline, venlafaxine, and bupropion (singularly and in mixture) on C-start escape behavior were evaluated in fathead minnows (Pimephales promelas). Embryos (postfertilization until hatching) were exposed for 5 d and, after hatching, were allowed to grow in control well water until 12 d old. Similarly, posthatch fathead minnows were exposed for 12 d to these compounds. High-speed (1,000 frames/s) video recordings of escape behavior were collected and transferred to National Institutes of Health Image for frame-by- frame analysis of latency periods, escape velocities, and total escape response (combination of latency period and escape velocity). When tested 12 d posthatch, fluoxetine and venlafaxine adversely affected C-start performance of larvae exposed as embryos. Conversely, larvae exposed for 12 d posthatch did not exhibit altered escape responses when exposed to fluoxetine but were affected by venlafaxine and bupropion exposure. Mixtures of these four antidepressant pharmaceuticals slowed predator avoidance behaviors in larval fathead minnows regardless of the exposure window. The direct impact of reduced C-start performance on survival and, ultimately, reproductive fitness provides an avenue to assess the ecological relevance of exposure in an assay of relatively short duration.

  4. Subchronic effects of five di-ortho PCB congeners on survival, growth and reproduction in the fathead minnow Pimephales promelas

    SciTech Connect

    Suedel, B.C.; Dillon, T.M.; Benson, W.H.

    1997-07-01

    The effects of five di-ortho polychlorinated biphenyl (PCB) congeners on survival, growth, and reproduction in the fathead minnow. Pimephales promelas, were determined. Fish were exposed to one of two nominal concentrations of each congener for a total of 13 weeks (7-week prespawning period plus 6-week spawning period) under flow-through conditions using methanol as a carrier solvent. At termination, P. promelas survival was high in all PCB congener treatments. PCB congeners had no significant sublethal effects on reproductive success within the concentration range examined. The total number of eggs, clutch size, number of clutches, percent hatchability, and presence of terata in offspring were not significantly affected. Reproductive success was slightly but not significantly enhanced in the solvent control and high treatment concentrations for congeners 52, 101, 138, and 153. Growth expressed as wet weight was not affected for both adult males or females. Male lengths were not significantly affected but female lengths were significantly reduced when exposed to congeners 101, 138, 153, and 180. Pimephales promelas accumulated substantial amounts of all PCBs, with tissue concentrations ranging from 13 to 183 mg/kg wet weight at termination in PCB-exposed fish. These tissue residues are one to several orders of magnitude greater than those reported for these congeners in aquatic biota previously collected in industrial waterways of the Great Lakes. Several di-ortho PCB congeners frequently found in aquatic biota showed minimal adverse effects on fathead minnow survival, growth, and reproduction even though bioaccumulation of these congeners was substantial.

  5. Reduction in organic effluent static acute toxicity to fathead minnows by various aeration techniques.

    PubMed

    Belanger, S E; Farris, J L; Cherry, D S

    1988-01-01

    This study compared results of no aeration, intermittent aeration, and constant aeration strategies in determining the static acute (48-h) toxicity of phenolic-based effluents to adult fathead minnows (Pimephales promelas). Toxicity was greatest in no aeration tests followed by intermittent aeration and constant aeration. Two factors were considered responsible for the observed patterns of toxicity. First, in side-by-side tests of no versus intermittent aeration and intermittent versus constant aeration, toxicity reductions were directly attributed to maintenance of dissolved oxygen above 5.0 mg litre(-1) in aerated containers. Secondly, toxicity was reduced when treatment system temperatures were warmest, probably due to increased microbial activity and volatilisation during late spring to early autumn (temperatures > 16 degrees C). Effluent was slightly more toxic on- than off-site, presumably due to degradation of phenolic compounds during transport and set-up at the off-site laboratory (approximately 4.5 h). Gill tissue ultrastructure and histopathology were used to determine the extent of effluent-induced damage and the recovery of minnows to short (6-h) effluent exposures. After a 48-h exposure to the approximate LC(50) level, gill tissue lamellae were characteristically desquamated with epithelium lifting from the basement membrane. Gill tissue was similarly damaged after a 6-h exposure to 100% effluent and had recovered to pre-exposure conditions after 42 h in clean water. Aeration strategies in these studies demonstrated potential air-stripping of volatile compounds, although stress to test organisms from low dissolved oxygen was relieved.

  6. Channel catfish polyculture with fathead minnows or threadfin shad effects on pond plankton communities and catfish fillet flavor, color, and fatty acid composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Threadfin shad, Dorosoma petenense, or fathead minnows, Pimephales promelas, were co-cultured with channel catfish, Ictalurus punctatus, in earthen ponds to determine the effects of planktivory on plankton community dynamics and catfish fillet quality. Fathead minnows had no effect on the plankton c...

  7. Multiple computer-automated structure evaluation study of aquatic toxicity. 2. Fathead minnow

    SciTech Connect

    Klopman, G.; Saiakhov, R.; Rosenkranz, H.S.

    2000-02-01

    An acute toxicity model was constructed on the basis of experimental data for 685 chemicals tested for toxicity for fathead minnow. The multiple computer-automated structure evaluation (M-CASE) program was used for the construction of the model. Based on a comparison between the authors results and published results, the authors found that the methodology is able to describe acute toxicity for the fathead minnow with high accuracy. The model incorporates the concept of a baseline activity as one of the parameters for the correlation as well as other parameters such as the presence of biophores, hardness-softness parameters, and other characteristics determined from quantum mechanical calculations. By using its artificial intelligence algorithm, M-CASE chooses automatically the most suitable set of parameters for evaluating the minnow toxicity of any organic molecule. The authors found that M-CASE can correctly predict acute toxicity for minnow for 80% of organic compounds with an average error of only 0.4 log units of lethal dose. The main toxicophores, corresponding to polar narcosis and to other types of reactive chemicals, were identified.

  8. Fathead minnow and bluegill sunfish life-stage responses to 17β-estradiol exposure in outdoor mesocosms

    USGS Publications Warehouse

    Elliott, Sarah M.; Kiesling, Richard L.; Jorgenson, Zachary G.; Rearick, Daniel C.; Schoenfuss, Heiko L.; Fredricks, Kim T.; Gaikowski, Mark P.

    2014-01-01

    Developmental and reproductive effects of 17β-estradiol (E2) exposure on two generations of fathead minnows and one generation of bluegill sunfish were assessed. Fish were exposed to E2 for six continuous weeks in outdoor mesocosms simulating natural lake environments. First generation fish were exposed while sexually mature. Second generation fathead minnows were exposed either during early development, sexual maturity, or both stages. Multiple endpoints were measured to assess effects of E2 exposure on fecundity and fish health and development. Plasma vitellogenin concentrations were highly variable in all fish. Differences in egg production timing for both species indicate differences in fecundity between females exposed to E2 and controls. First generation fathead minnows exposed to E2 had lower body condition factors and reduced secondary sexual characteristic expression by males. Only a difference in relative liver weight was observed in second generation fathead minnows. First generation bluegill males exposed to E2 had significantly smaller testes compared to controls. Although fish response was highly variable, results indicate that exposure to E2 at environmentally relevant concentrations affect fathead minnow and bluegill sunfish health and development, which may have implications for the health and sustainability of fish populations. Furthermore, exposure timing and environmental factors affect fish response to E2 exposure.

  9. Reproductive and tolerance effects of chronic fluoranthene exposure in a laboratory population of fathead minnows

    SciTech Connect

    Diamond, S.A.; Oris, J.T.; Guttman, S.I.

    1994-12-31

    An on-going full life cycle, multigeneration exposure is being conducted to assess the long-term effects of fluoranthene exposure in the presence of solar ultraviolet radiation on the fathead minnow. An experimental population of 200 fish has been exposed to 7.9 {mu}g fluoranthene{sm_bullet}{vert_bar}{sup {minus}1} continuously from juvenile stage through breeding. The Fl generation has been hatched and reared to adult stage within isolation chambers in the exposure tank. During the 16 wk breeding period egg production in the exposed population averaged 75% relative to an identical control population. hatching success of exposed eggs, and larval survivorship to 10 days, were 61% and 44% of controls respectively. No larval growth differences were detected. A test for tolerance acquisition in the exposed population using replicate 96 hr LC50 values revealed no significant difference between the populations. However, the distribution of concentration-mortality values suggested that the two populations responded differently to exposure. To examine this apparent difference eggs were removed from the exposure tank, hatched, and larvae were reared in uncontaminated water. These fish were then simultaneously exposed with identically treated control fish to 27.4{mu}g fluoranthene{sm_bullet}{vert_bar}{sup {minus}1}. The LT50 time for control fish (120 hr) was shorter than the LT50 time exposed fish (146 hr). These results suggest that differential egg production and hatching success, as well as larval survivorship, has resulted in genetic adaptation to fluoranthene exposure.

  10. Effects of progesterone and norethindrone on female fathead minnow (Pimephales promelas) steroidogenesis.

    PubMed

    Petersen, Lene H; Hala, David; Carty, Dennis; Cantu, Mark; Martinović, Dalma; Huggett, Duane B

    2015-02-01

    As knowledge of contaminants capable of adversely modulating endocrine functions increases, attention is focused on the effects of synthetic progestins as environmental endocrine disrupters. In the present study, effects of exposure to a synthetic progestin (norethindrone, 168 ± 7.5 ng/L) and endogenous progestogen (progesterone, 34 ± 4.1 ng/L) on steroidogenesis in adult female fathead minnows were examined. In vivo exposure to either compound lowered expression (nonsignificant) of luteinizing hormone (LHβ) levels in the brain along with significantly down-regulating the beta isoform of membrane progesterone receptor (mPRβ) in ovary tissue. The correspondence between lowered LHβ levels in the brain and mPRβ in the ovary is suggestive of a possible functional association as positive correlations between LHβ and mPR levels have been demonstrated in other fish species. In vitro exposure of ovary tissue to progesterone resulted in significantly elevated progestogen (pregnenolone, 17α-hydroxyprogesterone, and 17α,20β-dihydroxypregnenone) and androgen (testosterone) production. Whereas in vitro exposure to norethindrone did not significantly impact steroid hormone production but showed decreased testosterone production relative to solvent control (however this was not significant). Overall, this study showed that exposure to a natural progestogen (progesterone) and synthetic progestin (norethindrone), was capable of modulating LHβ (in brain) and mPRβ expression (in ovary). PMID:25470578

  11. Consumption estimates of walleye stocked as fry to suppress fathead minnow populations in west-central Minnesota wetlands

    USGS Publications Warehouse

    Ward, M.C.; Willis, D.W.; Herwig, B.R.; Chipps, S.R.; Parsons, B.G.; Reed, J.R.; Hanson, M.A.

    2008-01-01

    Fisheries managers throughout the Prairie Pothole Region of Minnesota often use semi-permanent and permanent wetland basins to extensively culture walleye Sander vitreus fry. Waterfowl managers have expressed concern over this practice because of the potential influence that fish have on food resources used by waterfowl during development and migration. It is well known that native fathead minnows Pimephales promelas can have detrimental effects on macroinvertebrates, zooplankton, water clarity, epiphyton, and macrophytes in wetlands. Because walleye commonly become piscivorous as soon as mouth gape allows, walleye fry may suppress fathead minnow populations and improve wetland conditions for waterfowl. In this study, we quantify consumption estimates, specifically predation on fathead minnows, by age-0 and age-1 walleye reared in natural wetland basins. Six wetlands were stocked in mid-May 2001 and 2002 at a rate of 12,000 walleye fry ha-1. Age-0 walleye were sampled bi-weekly from mid-June through mid-September 2001. Age-0 and age-1 walleye were sampled monthly from mid-May through mid-September 2002. A generalised diet shift from zooplankton to fish to macroinvertebrates was observed in 2001, whereas diets of juvenile walleye contained primarily macroinvertebrates in 2002. Stocked walleye quickly reduced fathead minnow populations in 2001 and suppression was maintained throughout 2002. Although walleye consumed primarily macroinvertebrates once prey fish populations became suppressed, consumption estimates of invertebrates by walleye were substantially less than those documented for fathead minnow populations. Thus, stocking age-0 walleye was an effective biomanipulation tool that substantially reduced fathead minnow densities and influenced lower trophic levels in these aquatic communities. ?? 2007 Blackwell Munksgaard.

  12. Modeling the accumulation of three waterborne chlorinated ethanes in fathead minnows (Pimephales promelas): A physiologically based approach

    SciTech Connect

    Lien, G.J.; Nichols, J.W.; McKim, J.M. . Environmental Research Lab.); Gallinat, C.A. )

    1994-07-01

    A physiologically based kinetic model was used to predict the accumulation of a homologous series of chlorinated ethanes in fathead minnows (Pimephales promelas). Uptake and accumulation of these compounds are described in terms of a few fundamental physiological, morphological, and physicochemical parameters. Chemical residues in 30-d-old fathead minnows exposed to 1,1,2,2-tetrachloroethane, pentachloroethane, and hexachloroethane were used to evaluate model performance. The predicted and observed accumulations of the chlorinated ethanes were in close agreement. A quantitative assessment of the major factors regulating the exchanged of these compounds indicates that the cutaneous surface may be an important route of uptake in small fish.

  13. Modeling the accumulation of three waterborne chlorinated ethanes in fathead minnows ( pimephales promelas'): A physiologically based approach

    SciTech Connect

    Lien, G.J.; Nichols, J.W.; McKim, J.M.; Gallinat, C.A.

    1994-01-01

    A physiologically based kinetic model was used to predict the accumulation of a homologous series of chlorinated ethanes in fathead minnows (Pimephales promelas). Uptake and accumulation of these compounds are described in terms of a few fundamental physiological, morphological, and physicochemical parameters. Chemical residues in 30-d-old fathead minnows exposed to 1,1,2,2-tetrachloroethane, pentachloroethane, and hexachloroethane were used to evaluate model performance. The predicted and observed accumulations of the chlorinated ethanes were in close agreement. A quantitative assessment of the major factors regulating the exchange of these compounds indicates that the cutaneous surface may be an important route of uptake in small fish.

  14. Influence of copper exposure on whole-body sodium levels in larval fathead minnows (Pimephales promelas).

    PubMed

    Van Genderen, Eric J; Tomasso, Joseph R; Klaine, Stephen J

    2008-06-01

    Because metals such as Cu inhibit ionoregulation, the increased energy requirement to counter passive diffusive losses in soft water may translate into increased sensitivity to metal exposure. We developed a method to determine whole-body Na concentrations of larval fathead minnows (Pimephales promelas) as a physiological indicator of health. This method was used to characterize net rates of Na flux from fish exposed to Cu in the presence of varying levels of hardness and alkalinity. In extremely soft waters (hardness, < or = 10 mg/L as CaCO(3)), larval fish experienced rates of net whole-body Na loss greater than what has been observed in juvenile and adult fish when exposed to Cu at concentrations near the median lethal concentration. Elevating hardness (>10 mg/L as CaCO(3)), however, decreased the apparent kinetics of Na loss caused by Cu exposure, which suggests the process was related to uncompetitive inhibition of Cu by hardness cations. Although the percentage of Na loss associated with mortality in larval fish was similar to that in juvenile and adult fish (30% loss of exchangeable Na pool), larvae reached this level within 12 h of exposure, and it was not representative of the onset of mortality. These results suggested that ionoregulatory measures by themselves are not a conclusive metric for Cu regulation using larval fish. To account for increased sensitivity in low-hardness waters in the development of biotic ligand models, the critical amount of Cu associated with the gill to cause mortality (i.e., the median lethal accumulation value) should be characterized more appropriately as a function of hardness below 20 mg/L as CaCO(3).

  15. A new bacilliform fathead minnow rhabdovirus that produces syncytia in tissue culture.

    PubMed

    Iwanowicz, L R; Goodwin, A E

    2002-05-01

    A pathogenic bacilliform virus 130-180 nm in length and 31-47 nm in diameter was isolated from moribund fathead minnows (Pimephales promelas) exhibiting hemorrhages in their eyes and skin. A cytopathic effect of multifocal syncytia was observed in the epithelioma papulosum cyprini cell line after a 48 h incubation at 20 degrees C. A similar cytopathic effect was also observed in other cell lines tested, but not in bluegill fry, koi fin, or Chinook salmon embryo cells. The filterable agent was inactivated by exposure to 50 degrees C for 10 min, 20% ether, 2 and 50% chloroform, pH 3, and pH 10, was unaffected by 5'-iodo-2 deoxyuridine, and appeared bacilliform and occasionally bullet-shaped by electron microscopy. These results are consistent with those of rhabdoviruses. Immunodot blots performed with antisera against selected fish rhabdoviruses, an aquareovirus, and a birnavirus were all negative. River's postulates were fulfilled in fathead minnows, but the agent did not replicate or cause disease in other cyprinids or salmonids during challenge experiments. Hepatic, splenic, and renal lesions were observed during histological analysis of diseased fish from viral challenges and from the original case. Structural proteins resolved via SDS-PAGE had molecular weights similar to those reported in lyssaviruses of the family Rhabdoviridae; however, syncytia formation is not a typical cytopathic effect of rhabdoviruses. This virus, has tentatively been named the fathead minnow rhabdovirus (FHMRV) and is most similar to the members of the family Rhabdoviridae, but atypical properties like syncytia formation may justify the assignment to a novel taxon.

  16. Mechanistic basis for estrogenic effects in fathead minnow (Pimephales promelas) following exposure to the androgen 17alpha-methyltestosterone: conversion of 17alpha-methyltestosterone to 17alpha-methylestradiol.

    PubMed

    Hornung, Michael W; Jensen, Kathleen M; Korte, Joseph J; Kahl, Michael D; Durhan, Elizabeth J; Denny, Jeffrey S; Henry, Tala R; Ankley, Gerald T

    2004-01-01

    Exposure of adult fathead minnows (Pimephales promelas) to the androgen 17alpha-methyltestosterone (MT) produces both androgenic and estrogenic effects, manifested as nuptial tubercle formation in females, and vitellogenin production in males and females, respectively. The present study was conducted to determine if the unanticipated estrogenic effects are produced by conversion of MT via aromatase activity to 17alpha-methylestradiol (ME2). Aromatase activity at the end of a 7-day waterborne MT exposure (20, 200microg/l) was significantly decreased in ovarian microsomes and brain homogenates from exposed fish, to about 30-50% of control activity. Although aromatase activity was decreased by 7 days, it is possible that the conversion of MT to ME2 occurred soon after initial exposure. In support of this, ME2 was detected in plasma samples of the fish following the 7-day exposure, confirming their ability convert the androgen MT to the estrogen ME2. The concentration of ME2 in plasma was within the range of plasma 17ss-estradiol (E2) found in control female fathead minnows (4-5ng/ml). These results, in conjunction with competitive binding assays that indicate ME2 binds to the fathead minnow estrogen receptor with a relative binding affinity of 68.3% of E2, support the hypothesis that aromatization of MT to ME2 contributes to the estrogenic effects in fathead minnows following exposure to this androgen.

  17. Selective uptake and biological consequences of environmentally relevant antidepressant pharmaceutical exposures on male fathead minnows

    USGS Publications Warehouse

    Schultz, M.M.; Painter, M.M.; Bartell, S.E.; Logue, A.; Furlong, E.T.; Werner, S.L.; Schoenfuss, H.L.

    2011-01-01

    Antidepressant pharmaceuticals have been reported in wastewater effluent at the nanogram to low microgram-per-liter range, and include bupropion (BUP), fluoxetine (FLX), sertraline (SER), and venlafaxine (VEN). To assess the effects of antidepressants on reproductive anatomy, physiology, and behavior, adult male fathead minnows (Pimephales promelas) were exposed for 21 days either to a single concentration of the antidepressants FLX, SER, VEN, or BUP, or to an antidepressant mixture. The data demonstrated that exposure to VEN (305. ng/L and 1104. ng/L) and SER (5.2. ng/L) resulted in mortality. Anatomical alterations were noted within the testes of fish exposed to SER and FLX, both modulators of the neurotransmitter serotonin. Additionally, FLX at 28. ng/L induced vitellogenin in male fish-a common endpoint for estrogenic endocrine disruption. Significant alterations in male secondary sex characteristics were noted with single exposures. Effects of single compound exposures neither carried over, nor became additive in the antidepressant mixtures, and reproductive behavior was not affected. Analysis of brain tissues from the exposed fish suggested increased uptake of FLX, SER and BUP and minimal uptake of VEN when compared to exposure water concentrations. Furthermore, the only metabolite detected consistently in the brain tissues was norfluoxetine. Similar trends of uptake by brain tissue were observed when fish were exposed to antidepressant mixtures. The present study demonstrates that anatomy and physiology, but not reproductive behavior, can be disrupted by exposure to environmental concentrations of some antidepressants. The observation that antidepressant uptake into fish tissues is selective may have consequences on assessing the mode-of-action and effects of these compounds in future studies. ?? 2011 Elsevier B.V.

  18. Selective uptake and biological consequences of environmentally relevant antidepressant pharmaceutical exposures on male fathead minnows

    USGS Publications Warehouse

    Schultz, Melissa M.; Painter, Meghan M.; Bartell, Stephen E.; Logue, Amanda; Furlong, Edward T.; Werner, Stephen L.; Schoenfuss, Heiko L.

    2011-01-01

    Antidepressant pharmaceuticals have been reported in wastewater effluent at the nanogram to low microgram-per-liter range, and include bupropion (BUP), fluoxetine (FLX), sertraline (SER), and venlafaxine (VEN). To assess the effects of antidepressants on reproductive anatomy, physiology, and behavior, adult male fathead minnows (Pimeplwles promelas) were exposed for 21 days either to a single concentration of the antidepressants FLX, SER, VEN, or BUP, or to an antidepressant mixture. The data demonstrated that exposure to VEN (305 ng/L and 1104 ng/L) and SER (5.2 ng/L) resulted in mortality. Anatomical alterations were noted within the testes of fish exposed to SER and FLX, both modulators of the neurotransmitter serotonin. Additionally, FLX at 28 ng/L induced vitellogenin in male fish—a common endpoint for estrogenic endocrine disruption. Significant alterations in male secondary sex characteristics were noted with single exposures. Effects of single compound exposures neither carried over, nor became additive in the antidepressant mixtures, and reproductive behavior was not affected. Analysis of brain tissues from the exposed fish suggested increased uptake of FLX, SER and BUP and minimal uptake of VEN when compared to exposure water concentrations. Furthermore, the only metabolite detected consistently in the brain tissues was norfluoxetine. Similar trends of uptake by brain tissue were observed when fish were exposed to antidepressant mixtures. The present study demonstrates that anatomy and physiology, but not reproductive behavior, can be disrupted by exposure to environmental concentrations of some antidepressants. The observation that antidepressant uptake into fish tissues is selective may have consequences on assessing the mode-of-action and effects of these compounds in future studies.

  19. EVALUATION OF THE AROMATASE INHIBITOR FADROZOLE IN A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Cytochrome P450 aromatase is a key enzyme in vertebrate steroidogenesis, catalyzing the conversion of C19 androgens to C18 estrogens such a B-estradiol (E2). The objective of this study was to assess effects of the CYP inhibitor fadrozole on fathead minnow reproductive endocrinol...

  20. CHARACTERIZATION OF RESPONSES TO THE ANTIANDROGEN FLUTAMIDE IN A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW

    EPA Science Inventory

    A short-term reproduction assay with the fathead minnow has been developed to detect chemicals with the potential to disrupt reproductive endocrine functions controlled by estrogen- and androgen-mediated pathways. The objective of this study was to characterize the responses of t...

  1. A computational model linking oocyte growth and spawning to the hypothalamic-pituitary-gonadal axis in fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Reproduction is vital to the survival of all living organisms, and reproductive toxicity is an important outcome in determining the ecological risks of chemicals in the environment. To evaluate reproductive toxicity, fathead minnow fecundity, as measured by the average number of...

  2. NMR ANALYSIS OF MALE FATHEAD MINNOW URINARY METABOLITES: A POTENTIAL APPROACH FOR STUDYING IMPACTS OF CHEMICAL EXPOSURES

    EPA Science Inventory

    The potential for profiling endogenous metabolites in urine from male fathead minnows (Pimephales promelas) to assess chemical exposures was explored using nuclear magnetic resonance (NMR) spectroscopy. Both one dimensional (1D) and two dimensional (2D) NMR spectroscopy w...

  3. Human low density lipoprotein as a substrate for in vitro steroidogenesis assays with fathead minnow ovary explants

    EPA Science Inventory

    Gonad explant in vitro steroidogenesis assays are used as part of a multifaceted strategy to detect endocrine active chemicals capable of altering steroid hormone synthesis. An in vitro steroidogenesis assay used in our laboratory involves exposing fathead minnow (FHM) gonad exp...

  4. Observed and modeled effects of pH on bioconcentration of diphenhydramine, a weakly basic pharmaceutical, by fathead minnows

    EPA Science Inventory

    Understanding the influence of pH on uptake and accumulation of ionizable pharmaceuticals by fish was recently identified as a major research need. In the present study, fathead minnows were exposed to diphenhydramine (DPH), a weakly basic pharmaceutical (pKa = 9.1). Fish were ...

  5. Fishy aroma of social status: Urinary chemo-signaling of territoriality in male fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Fathead minnows (Pimephales promelas) exhibit life history traits which may be conducive to evolution of systems that use chemical communication to confer information about an individual’s social status. Reproduction in males of this species is dependent upon their ability ...

  6. Modulation of estrogenic exposure effects via alterations in salinity and dissolved oxygen in male fathead minnows, Pimephales promelas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laboratory exposure data indicate that estrogens and estrogen mimics can cause endocrine disruption in male fathead minnows (Pimephales promelas). In the wild, conditions are not static as is often the case in the laboratory. Changes in water quality parameters, such as salinity influx due to road s...

  7. Predicting Adaptive Response to Fadrozole Exposure:Computational Model of the Fathead MinnowsHypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict doseresponse and time-course (...

  8. Predicting Adaptive Response to Fadrozole Exposure: Computational Model of the Fathead Minnow Hypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (...

  9. Development of a Computational Model for Female Fathead Minnows Exposed to 17a-ethynylestradiol and 17B-trenbolone

    EPA Science Inventory

    The fathead minnow (FHM) is a valuable small fish model for genomic research in ecotoxicology. Our recent studies have successfully used genomic and metabolomic analyses to evaluate responses to endocrine disrupting compounds (EDCs) in urine of the FHM, but these results indicate...

  10. Investigating Compensation and Recovery of Fathead Minnow (Pimephales promelas) Exposed to 17α-Ethynylestradiol with Metabolite Profiling

    EPA Science Inventory

    1H-NMR spectroscopy was used to profile metabolite changes in the livers of fathead minnows (Pimephales promelas) exposed to the synthetic estrogen 17α ethynylestradiol (EE2) via a continuous flow water exposure. Fish were exposed to either 10 or 100 ng EE2/L for 8 days, followed...

  11. A COMPARISON OF THE LETHAL AND SUBLETHAL TOXICITY OF ORGANIC CHEMICAL MIXTURES TO THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    The joint toxic effects of known binary and multiple organic chemical mixtures to the fathead minnow (Pimephales promelas) were defined at both the 96-h 50% lethal effect concentration (LC50) and sublethal (32-d growth) response levels for toxicants with a narcosis I, narcosis II...

  12. PREDICTION OF THE ACUTE TOXICITY OF ORGANIC COMPOUNDS TO THE FATHEAD MINNOW (PIMEPHALES PROMALAS) USING A GROUP CONTRIBUTION METHOD

    EPA Science Inventory

    A group contribution method has been developed to correlate the acute toxicity (96 h LC50) to the fathead minnow (Pimephales promelas) for 379 organic chemicals. Multilinear regression and computational neural networks (CNNs) were used for model building. The multilinear linear m...

  13. SUBCHRONIC SENSITIVITY OF ONE-, FOUR-, AND SEVEN-DAY-OLD FATHEAD MINNOW (PIMEPHALES PROMELAS) LARVAE TO FIVE TOXICANTS

    EPA Science Inventory

    The fathead minnow (pimephales promelas) larval survival and growth test was used to evaluate the relative sensitivity of 1-,4-, and 7-d-old larvae to five contaminants, KC1, NaC1, 1-octanol, carbaryl, and benzaldehyde. The no observable effect concentration (NOEC) for survival o...

  14. Adaptive Response in Female Fathead Minnows Exposed to an Aromatase Inhibitor: Computational Modeling of the Hypothalamic-Pituitary-Gonadal Axis

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course ...

  15. Effects-based Monitoring with Caged Fathead Minnows: An Exposure Gradient Case Study in the Duluth-Superior Harbor, USA

    EPA Science Inventory

    Within the Great Lakes there is an increased focus on contaminants of emerging concern (CECs) and consideration of potential effects of chemical mixtures. To further characterize the utility of caged fathead minnows (Pimephales promelas) for effects-based monitoring of CECs, we c...

  16. Acute toxicity of firefighting chemical formulations to four life stages of fathead minnow

    USGS Publications Warehouse

    Gaikowski, Mark P.; Hamilton, Steve J.; Buhl, Kevin J.; McDonald, Susan F.; Summers, Cliff H.

    1996-01-01

    Laboratory studies were conducted with four early life stages of fathead minnow,Pimephales promelas,to determine the acute toxicity of five firefighting chemical formulations in standardized soft and hard water. Egg, fry, 30-day posthatch, and 60-day posthatch life stages were tested with three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two fire-suppressant foams (Phos-Chek WD-881 and Ansul Silv-Ex). Fry were generally the most sensitive life stage tested, whereas the eggs were the least sensitive life stage. Formulation toxicity was greater in hard water than in soft water for all life stages tested. Fire-suppressant foams were more toxic than the fire retardants. The 96-hr LC50s derived for fathead minnows were rank ordered from the most toxic to the least toxic formulation as follows: Phos-Chek WD-881 (13a??32 mg/liter) > Silv-Ex (19a??32 mg/liter) > Fire-Trol GTS-R (135a??787 mg/liter) > Phos-Chek D75-F (168a??2250 mg/liter) > Fire-Trol LCG-R (519a??6705 mg/liter) (ranges are the lowest and highest 96-hr LC50for each formulation). (C) 1996 Academic Press, Inc.

  17. Lethal body concentrations of four non-polar narcotic chemicals in larval fathead minnows (Pimephales promelas)

    SciTech Connect

    Groetsch, K.; Oris, J.T.; Versteeg, D.J.

    1995-12-31

    The objective of this study was to evaluate the lethal body concentrations of tetra chloroethane, dichlorobenzene, pentachlorobenzene, and hexachlorobenzene in the larval fathead minnow (Pimephales promelas). The authors exposed similar populations of larval fathead minnows to a range of concentrations of one of four non-polar, narcotic chemicals. Morbid larvae were collected and the time of collection and internal body concentration were recorded. Example results for pentachlorobenzene show that the concentration of chemical in larvae that die in short time intervals were significantly lower than the concentration of chemical in larvae that died later in the test (ANOVA F-Value = 139, P-Value <.0001). Morbidity occurred between 16 and 210 hours of exposure. After 210 hours, exposed individuals had similar rates of morbidity compared to controls. This study corroborates other research that suggests the existence of a threshold body concentration that causes lethality for non-polar narcotic chemicals. However, individual based tolerance appears to contribute significantly to variability in lethal body concentrations.

  18. Transcriptional signature of progesterone in the fathead minnow ovary (Pimephales promelas).

    PubMed

    Garcia-Reyero, Natàlia; Martyniuk, Christopher J; Kroll, Kevin J; Escalon, B Lynn; Spade, Daniel J; Denslow, Nancy D

    2013-10-01

    A growing number of studies have examined transcriptional responses to sex steroids along the hypothalamic-pituitary-gonadal axis in teleost fishes. However, data are lacking on the molecular cascades that underlie progesterone signaling. The objective of this study was to characterize the transcriptional response in the ovary of fathead minnows (Pimephales promelas) in response to progesterone (P4). Fathead minnow ovaries were exposed in vitro to 500 ng P4/L. Germinal vesicle migration and breakdown (GVBD) was observed and microarrays were used to identify gene cascades affected by P4. Microarray analysis identified 1702 differentially expressed transcripts after P4 treatment. Functional enrichment analysis revealed that transcripts involved in the molecular functions of protein serine/threonine kinase activity, ATP binding, and activity of calcium channels were increased after P4 treatment. There was an overwhelming decrease in levels of transcripts of genes that are structural constituents of ribosomes with P4 treatment. There was also evidence for gene expression changes in steroid and maturation-related transcripts. Pathway analyses identified cell cycle regulation, insulin action, hedgehog, and B cell activation as pathways containing an over-representation of highly regulated transcripts. Significant regulatory sub-networks of P4-mediated transcripts included genes regulated by tumor protein p53 and E2F transcription factor 1. These data provide novel insight into the molecular signaling cascades that underlie P4-signaling in the ovary and identify genes and processes that may indicate premature GVBD due to environmental pollutants that mimic progestins.

  19. Fathead minnow FHM cells for use in in vitro cytotoxicity assays of aquatic pollutants

    SciTech Connect

    Babich, H.; Borenfreund, E.

    1987-08-01

    The suitability of the fathead minnow (FHM) epithelial cell line for use as the target (indicator) system in in vitro cytotoxicity assays was evaluated using several endpoints. The organometal diethyltin dichloride served as the representative test agent. The concentration of diethyltin dichloride which resulted in a midpoint toxicity was 3.5 microM in a 3-day cell growth assay, 3.8 microM in the 24-hr neutral red assay, and 16.5 microM in a 4-hr cell detachment assay. The neutral red assay was used to compare the relative sensitivities of the FHM cells (exposed at 34/sup 0/C) with those of bluegill sunfish (BF-2) cells, a fibroblastic cell culture (exposed at 26 degrees C), in the presence of different classes of test agents frequently occurring as aquatic pollutants. For both fish species the sequence of potencies of the test agents was in the order of organometals greater than pesticides approximately equal to polychlorinated biphenyls greater than polynuclear aromatic hydrocarbons greater than phenolics. Overall, the FHM cells were more sensitive than were the BF-2 cells. However, there was a better correlation between the in vitro cytotoxicity data for the BF-2 cell culture and LC50 data for bluegill sunfish than between similar data for the FHM cell line and fathead minnows.

  20. Reciprocal influences of temperature and copper on survival of fathead minnows, Pimephales promelas

    SciTech Connect

    Richards, V.L.; Beitinger, T.L.

    1995-08-01

    Contemporary ecological concerns of accelerated global warming, increase in toxic chemicals and loss of biodiversity make relevant studies of tolerance of various organisms to abiotic variables. In this study, the reciprocal effects of temperature and copper on survival of fathead minnows, Pimephales promelas, were determined. Temperature tolerance of fishes is limited by a cornucopia of biotic and abiotic factors, including various toxicants. Not only do chemicals affect temperature tolerance of fishes, temperature influences the sensitivity of fish to toxic chemicals; however, the relationship between temperature and lethality is complex, difficult to predict, and has not been the focus of many studies. Copper, a necessary trace element in animal metabolism and ubiquitous in aquatic environments, was selected as our test toxicant. Hodson et al. (1979) reported copper concentrations of one to 29 {mu}g/L in unpolluted surface waters in the United States. Copper sulfate (CuSO{sub 4}), is an algicide, bactericide and herbicide for ponds, lakes and fish hatcheries. Also, copper is recommended as a fungicide for a variety of ornamental plants and crops, and in various chemical forms enters the environment through mining, smelting, and refining activities. Copper is toxic in parts per billion concentrations ({mu}g/L) and is an EPA priority pollutant. In this research two null hypotheses were tested: (1) temperature has no effect on the lethality of copper sulfate, and (2) sublethal concentrations of copper do not affect the upper temperature tolerance of fathead minnows. It was found that acclimation temperature significantly affects the 96-hr median lethal concentration. Exposure to copper adversely affects the ability of minnows to withstand high temperatures. 14 refs., 3 figs.

  1. A time-course analysis of effects of the steroidogenesis inhibitor ketoconazole on components of the hypothalamic-pituitary-gonadal axis of fathead minnows (Presentation)

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconazo...

  2. A Time-course Analysis of Effects of the Steroidogenesis Inhibitor Ketoconazole on Components of the Hypothalamic-pituitary-gonadal Axis of Fathead Minnows

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconazo...

  3. Sex-specific gene expression in early life stage fathead minnows (Pimephales promelas) throughout development and after exposure to synthetic hormones

    EPA Science Inventory

    There is evidence that exposure to endocrine disrupting chemicals (EDCs) during early life stages can alter sex differentiation in fishes. Fathead minnows (Pimephales promelas) are commonly used as a model fish species in endocrine disruption studies. However, limited knowledge...

  4. A Time-course Analysis of Effects of the Steroidogenesis Inhibitor Ketoconazole on Components of the Hypothalamic-pituitary-gonadal Axis of Fathead Minnows

    EPA Science Inventory

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconaz...

  5. High intensity and prevalence of two species of trematode metacercariae in the fathead minnow (Pimephales promelas) with no compromise of minnow anti-predator competence.

    PubMed

    Wisenden, Brian D; Martinez-Marquez, Jorge Y; Gracia, Emilia S; McEwen, Daniel C

    2012-08-01

    Opportunity for parasites to manipulate host behavioral phenotype may be influenced by several factors, including the host ecology and the presence of cohabiting parasites in the same host. Metacercariae of Ornithodiplostomum ptychocheilus and "black spot" Crassiphiala bulboglossa have similar life cycles. Each parasite uses a littoral snail as a first intermediate host, fathead minnows as a second intermediate host, and a piscivorous bird as a final host. Metacercariae of black spot encyst in the dermal and epidermal tissues, while metacercariae of O. ptychocheilus encyst on the brain over a region that coordinates optomotor responses. Because of site differences within the host, we predicted that O. ptychocheilus metacercariae might manipulate the behavioral phenotype of minnows to facilitate transmission to the final host, but metacercariae of black spot would not. In our study population, prevalence was 100% for O. ptychocheilus , with an overall median intensity of 105 metacercariae per minnow. Prevalence of black spot was 60%, with a median abundance and intensity of 12 and 20 metacercariae per minnow for the overall sample and for infected fish, respectively. Minnows accumulated both parasites over time, producing significant correlations between intensity and minnow body length and between intensities of the 2 parasites. Minnows infected with black spot had on average twice as many O. ptychocheilus metacercariae as similar-sized minnows without any black spot cercariae. We found no correlation between body condition of minnows and intensity for either parasite. We measured 2 aspects of anti-predator competence to test for effects linked to parasite intensity. We found no correlation between intensity of either species of parasite and latency to behavioral response to attack from a mechanical model heron, nor was there any effect of parasite intensity on a measure of shoaling affinity. The absence of any detectable effect of metacercariae on anti

  6. Influence of dissolved organic matter on acute toxicity of zinc to larval fathead minnows (Pimephales promelas).

    PubMed

    Bringolf, Robert B; Morris, Brady A; Boese, Connie J; Santore, Robert C; Allen, Herbert E; Meyer, Joseph S

    2006-10-01

    We conducted laboratory toxicity tests in support of the development of a biotic ligand model (BLM) to predict acute toxicity of zinc (Zn) to fathead minnows (Pimephales promelas). To test the effect of dissolved organic matter (DOM) on Zn toxicity, we exposed larval fathead minnows to Zn in water containing elevated concentrations of dissolved organic carbon (DOC) in 96-h static-renewal toxicity tests. We tested DOM isolated from four surface waters: Cypress Swamp, Delaware; Edisto River, South Carolina; Suwannee River, Georgia; and Wilmington, Delaware, wastewater treatment effluent. The DOM isolates from the Edisto River and Wilmington wastewater treatment effluent contained elevated concentrations of NaCl (20-110x control NaCl) due to the use of a Na+-exchange resin to remove Ca2+ and Mg2+ during the DOM isolation process. Therefore, we also performed Zn toxicity tests in which we added up to 20 mM NaCl to exposure solutions containing Cypress Swamp and Suwannee River DOM. A threshold concentration of 11 mg DOC/L was needed to decrease Zn toxicity, after which the 96 h Zn LC50 was positively correlated with DOC concentration. Elevated NaCl concentrations did not alter Zn toxicity in the presence of DOM. In conjunction with data from other studies with fish and invertebrates, results of this study were used to calibrate Version 2.1.1 of the Zn BLM. BLM-predicted LC50s for our exposure waters containing elevated DOM concentrations were within the range of acceptable deviation relative to the observed LC50s (i.e., 0.5-2x observed LC50s); however, BLM-predicted LC50s for our exposure waters containing < 1 mg DOC/L were 2-3x lower than the observed LC50s (i.e., the BLM over-predicted the toxicity). Therefore, the current composite-species BLM for Zn could be improved for fathead minnows if that species were modeled separately from the other species used to calibrate Version 2.1.1. PMID:16788742

  7. Toxicity and bioaccumulation of 2,4,6-trinitrotoluene in fathead minnow (Pimephales promelas).

    PubMed

    Yoo, Leslie J; Lotufo, Guilherme R; Gibson, Alfreda B; Steevens, Jeffery A; Sims, Jerre G

    2006-12-01

    Few studies have determined the toxicity and bioaccumulation potential of explosive compounds in freshwater fish. In the present study, fathead minnow (Pimephales promelas) were exposed to a range of 2,4,6-trinitrotoluene (TNT) concentrations (0.44-44 micromol/L [0.1-10 mg/L] and 4.4-22.0 micromol/L [1.0-5.0 mg/L] in 4- and 10-d experiments, respectively). Median lethal concentrations of 11.93 micromol/L (2.7 mg/L; 95% confidence limit [CL], 10.29-13.83 micromol/L) and 9.68 micromol/L (2.20 mg/L; 95% CL, 9.17-10.22 micromol/L) were calculated in the 4- and 10-d experiments, respectively, and median lethal body residue of 101.0 micromol/kg (95% CL, 86.0-118.7 micromol/kg) was calculated in 4-d experiments. To study bioaccumulation, fish were exposed to 4.4 micromol/L (1 mg/L) of TNT for 12 h. Rapid bioaccumulation of TNT occurred within the first 10 min of exposure (ku = 30.4 L/kg/ h). Elimination of sigmaTNT (molar sum of TNT and degradation products 2- and 4-aminodinitrotoluenes) was fast, with an elimination rate (ke) of 2.24/h and a short half-life (0.31 h). The bioconcentration factors determined using 6-h mean tissue and water concentrations of sigmaTNT were 8.40 and 4.68 L/kg for the uptake experiment and the uptake portion of the elimination experiments, respectively. To determine the target organ for TNT in fish, juvenile fathead minnow were exposed to 2.2 micromol/L (0.5 mg/L) of [14C]TNT for 10 d. Radiolabeled compounds primarily bioaccumulated in the visceral tissues and spleen in comparison to gill, brain, muscle, and remainder tissue groups. The present study demonstrates the low bioaccumulation potential and rapid uptake of TNT in the fathead minnow.

  8. Evaluation of whole-mount in situ hybridization as a tool for pathway-based toxicological research with early-life stage fathead minnows.

    PubMed

    Cavallin, J E; Schroeder, A L; Jensen, K M; Villeneuve, D L; Blackwell, B R; Carlson, K; Kahl, M D; LaLone, C A; Randolph, E C; Ankley, G T

    2015-12-01

    Early-life stage fish can be more sensitive to toxicants than adults, so delineating mechanisms of perturbation of biological pathways by chemicals during this life stage is crucial. Whole-mount in situ hybridization (WISH) paired with quantitative real-time polymerase chain reaction (QPCR) assays can enhance pathway-based analyses through determination of specific tissues where changes in gene expression are occurring. While WISH has frequently been used in zebrafish (Danio rerio), this technology has not previously been applied to fathead minnows (Pimephales promelas), another well-established small fish model species. The objective of the present study was to adapt WISH to fathead minnow embryos and larvae, and use the approach to evaluate the effects of estrone, an environmentally-relevant estrogen receptor (ER) agonist. Embryos were exposed via the water to 0, 18 or 1800 ng estrone/L (0, 0.067 and 6.7nM) for 3 or 6 days in a solvent-free, flow-through test system. Relative transcript abundance of three estrogen-responsive genes, estrogen receptor-α (esr1), cytochrome P450-aromatase B (cyp19b), and vitellogenin (vtg) was examined in pooled whole embryos using QPCR, and the spatial distribution of up-regulated gene transcripts was examined in individual fish using WISH. After 3 days of exposure to 1800 ng estrone/L, esr1 and cyp19b were significantly up-regulated, while vtg mRNA expression was not affected. After 6 days of exposure to 1800 ng estrone/L, transcripts for all three genes were significantly up-regulated. Corresponding WISH assays revealed spatial distribution of esr1 and vtg in the liver region, an observation consistent with activation of the hepatic ER. This study clearly demonstrates the potential utility of WISH, in conjunction with QPCR, to examine the mechanistic basis of the effects of toxicants on early-life stage fathead minnows. PMID:26485527

  9. Assessing acute toxicities of pre- and post-treatment industrial wastewaters with Hydra attenuata: A comparative study of acute toxicity with the fathead minnow, Pimephales promelas

    SciTech Connect

    Fu, L.J.; Staples, R.E.; Stahl, R.G. Jr. . Haskell Lab. for Toxicology and Industrial Medicine)

    1994-04-01

    This study was undertaken to (a) determine wastewater treatment effectiveness using two freshwater organisms, (b) compare acute toxicity results from the two species exposed to the wastewaters, and (c) link acute and potential developmental toxicity of wastewaters in one organism. The acute toxicities of several pretreatment and post-treatment industrial waste-water samples wee evaluated with adult Hydra attenuata and fathead minnows. The acute LC50s agreed closely when results in Hydra attenuata were compared with those from fathead minnow tests. Acute LC50s ranged from 3 to >100% of samples with hydra, and from 1.0 to >100% of sample with fathead minnows. The results provided strong evidence of treatment effectiveness because toxicity decreased with progressive stages of treatment. Previously the Hydra Developmental Toxicity Assay was used as a prescreen mainly for in vitro assessment of developmental toxicity with pure compounds and to prioritized toxicants according to selective toxicity to the developing embryo. Recently the authors modified the assay for testing natural waters and wastewaters; hence, some of the wastewater samples also were tested for their developmental toxicity. In this case, the relative selective toxicity of these wastewater samples ranged from 0.7 to 2.1, indicating that no sample was uniquely toxic to the developing embryo, although acute toxicity was manifested. Overall, their results indicate the Hydra Assay functions appropriately in assessments of acute and developmental toxicity of industrial wastewaters and may be a simple and useful tool in a battery of tests for broader scale detection of environmental hazards.

  10. Atrazine reduces reproduction in fathead minnow (Pimephales promelas): raw data report

    USGS Publications Warehouse

    Tillitt, Donald E.; Papoulias, Diana M.; Whyte, Jeffrey J.; Richter, Catherine A.

    2014-01-01

    The herbicide, atrazine, routinely is observed in surface and groundwaters, particularly in the “corn belt” region, a high-use area of the United States. Atrazine has demonstrated effects on reproduction in mammals and amphibians, but the characterization of endocrine-related effects in fish has received only limited attention. Peak concentrations of atrazine in surface water of streams from these agricultural areas coincide with annual spawning events of native fishes. Consequently, there was an unacceptable level of uncertainty in our understanding of the risks associated with the periods of greatest atrazine exposure and greatest vulnerability of certain species of fishes. For this reason, a study of the effects of atrazine on fathead minnow reproduction was undertaken (Tillitt and others, 2010). This report provides the raw data from that study.

  11. Sub-lethal increases in salinity affect reproduction in fathead minnows.

    PubMed

    Hoover, Zachary; Weisgerber, Jordan N; Pollock, Michael S; Chivers, Douglas P; Ferrari, Maud C O

    2013-10-01

    Salinization poses a threat to many inland aquatic ecosystems, especially in areas where natural processes are compounded by anthropogenic salinization. Though physiological survival can be a challenge for stenohaline freshwater fishes facing increasing salinity, it is important to note that essential and complex activities such as reproduction may be affected well below physiological tolerance limits. Here, we exposed fathead minnows (Pimephales promelas) to four levels of salinity in order to assess any impacts on several egg production and behavioral endpoints. We found significant reductions in total eggs produced, percent fertilization, number of spawning days, clutch size, total time males spent in the nest, and duration of nest care events. Our data demonstrate that salinization can have negative effects on critical reproductive endpoints.

  12. Transfer of toxic concentrations of selenium from parent to progeny in the fathead minnow (Pimephales promelas)

    SciTech Connect

    Schultz, R.; Hermanutz, R.

    1990-01-01

    Selenium, an essential trace element, may become concentrated in aquatic ecosystems to levels that are toxic to fish. Finley (1985) and Gillespie and Baumann (1986) have shown that selenium in overflow water from coal burning power plant settling basins contributed to a decline in fish populations. The leaching of selenium from the soil into water systems used for irrigation in highly seleniferous areas of the country poses another serious problem. Studies demonstrated that female bluegill sunfish transfer selenium to their progeny. The objective of the study was to determine whether the selenium levels within fathead minnow embryos in a semi-natural ecosystem resulted from direct uptake by the embryos following spawning, from female-to-progeny transferral, or from some combination of these two occurrences.

  13. Laboratory assessment of the toxicity of urban runoff on the fathead minnow (Pimephales promelas)

    SciTech Connect

    Medeiros, C.; Coler, R.A.; Calabrese, E.J.

    1984-01-01

    The early life stage effects of urban runoff (rain and snowmelt) on hatching, growth and survival of the fathead minnow (Pimephales promelas) was assessed in static and flow-through systems. The data indicate a Maximum Allowable Toxicant Concentration (MATC) and a reduction of growth to 50% of controls at 28% and 60% runoff, respectivley. Hatchability and average lengths were not as sensitive indicators of stress as millimeters produced per treatment. The data indicate a maximum toxicity in the fall which coincided with the reported drop in macroinvertebrate diversity during the same period, when untreated runoff events can contribute up to 1/4 of the river flow. The reduced diversity may be attributed to leachability and potential availability of sorbed concentrations of copper, lead, zinc, and cadmium in river sediments.

  14. Acute toxicity of hydrazine hydrate to the fathead minnow (Pimephales promelas) and daphnid (Daphnia pulex)

    SciTech Connect

    Velte, J.S.

    1984-11-01

    Utilities that depend on steam generation for the production of electricity have benefitted greatly from the use of hydrazine (H/sub 2/NNH/sub 2/). The chemical is a strong antioxidant that reacts with oxygen in water to form water and nitrogen gas. Deoxygenated boiler water helps reduce oxidation inside boilers and steam systems, thereby increasing their efficiency and longevity. Idle boilers are protected with layup solutions of hydrazine in concentrations as high as 200 mg/L. Hydrazine may enter the aquatic environment as controlled industrial discharge or as a result of an accidental spill. Data on the aquatic toxicity of hydrazine hydrate, however, are lacking. This paper addresses the acute toxicity of hydrazine hydrate to a freshwater fish (fathead minnow, Pimephalas promelas) and invertebrate (daphnid, Daphnia pulex).

  15. Hexachlorobenzene uptake by fathead minnows and macroinvertebrates in recirculating sediment/water systems

    SciTech Connect

    Schuytema, G.S.; Krawczyk, D.F.; Griffis, W.L.; Nebeker, A.V.; Robideaux, M.L.

    1990-01-01

    Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were maintained by recirculation through HCB-packed columns. Recirculating HCB-bound particulates and possibly eroded HCB particulates were an added source of HCB in addition to the sediment bed. Significant bioaccumulation of HCB in animal tissues was observed in water-only and water-sediment exposures. The presence of the HCB-spiked sediment did not result in a significant increase in the uptake of HCB by the organisms, but there was a substantial increase in sediment HCB levels over time. Higher tissue HCB levels in aquaria without sediment suggest that the sediment was a more efficient sink for HCB than the organisms.

  16. Relationship of plasma sex steroid concentrations in female fathead minnows to reproductive success and population status.

    PubMed

    Ankley, Gerald T; Miller, David H; Jensen, Kathleen M; Villeneuve, Daniel L; Martinović, Dalma

    2008-06-01

    Concentration and/or production of sex steroids such as 17beta-estradiol (E2) and testosterone (T) in fish have commonly been measured in field studies concerned with endocrine-active chemicals. There is a reasonable mechanistic basis for using E2 or T as biomarkers, as chemicals can alter steroid production through both direct and indirect effects on the hypothalamic-pituitary-gonadal (HPG) axis. There is uncertainty, however, as to what changes in steroid status may mean relative to apical endpoints, such as reproduction, that directly affect population status. In this study, we analyzed data from fathead minnow (Pimephales promelas) reproduction studies in which decreases in fecundity were associated with depressed steroid production as a result of chemical exposure. Although the chemicals acted on the HPG axis through different mechanisms, reproductive effects appeared to be expressed through a common pathway, depression of vitellogenin production in females. Plasma concentrations of E2 or T in the females were significantly, positively correlated with fecundity. Linear regression models describing the relationship between E2 or T concentrations and relative fecundity were linked to a population model to predict population trajectories of fathead minnows exposed to chemicals that inhibit steroid production. For example, a population existing at carrying capacity and exposed to a chemical stressor(s) that causes a 50% decrease in E2 production was predicted to exhibit a 92% decrease in population size over a 5-year period. Results of our analysis illustrate a conceptual framework whereby a commonly measured biomarker, sex steroid status, could be linked to individual- and population-level effects in fish.

  17. Effects of androstenedione exposure on fathead minnow (Pimephales promelas) reproduction and embryonic development.

    PubMed

    DeQuattro, Zachary A; Hemming, Jocelyn D C; Barry, Terence P

    2015-11-01

    High concentrations (300 ng/L) of androstenedione (A4) were identified in snowmelt runoff from fields fertilized with manure from livestock feeding operations in Wisconsin, USA. In fishes, A4 is an active androgen and substrate for biosynthesis of functional androgens (e.g., testosterone and 11-ketotestosterone) and estrogens (e.g., estradiol-17β). Thus, A4 has the potential to be a powerful endocrine disruptor. This hypothesis was tested by exposing reproductively mature fathead minnows to 0.0 ng/L, 4.5 ng/L, 74 ng/L, and 700 ng/L A4 for 26 d in a flow-through system. Various reproductive endpoints were measured including fecundity, fertilization success, secondary sexual characteristics, gonadosomatic index (GSI), and hepatic vitellogenin messenger RNA (mRNA) expression. In addition, fertilized embryos from the reproduction assay were used in an embryonic development assay to assess A4 effects on development and hatchability. In males, A4 significantly increased Vtg mRNA expression (estrogenic effect), significantly reduced GSI, and had no effect on tubercle expression (p = 0.067). In females, A4 induced tubercle development (androgenic effect) with no effects on GSI. Fecundity was not significantly impacted. Exposure to A4 had no effect on fertilization, embryonic development, or hatchability. These data indicate that exogenous A4, at environmentally relevant concentrations, can significantly modulate the reproductive physiology of the fathead minnows in a sex-specific manner and that A4 should be monitored as an endocrine disruptor. PMID:26053090

  18. Effects of a fire-retardant chemical to fathead minnows in experimental streams

    USGS Publications Warehouse

    Calfee, R.D.; Little, E.E.

    2003-01-01

    Background. Each year millions of liters of fire-retardant chemicals are applied to wildfires across the nation. Recent laboratory studies with long-term fire-retardant chemicals indicate a significant photoenhanced toxicity of products containing sodium ferrocyanide corrosion inhibitors. Our objective of this study was to determine the toxicity of fire-retardant chemicals to fathead minnows during exposure in experimental outdoor streams. Methods. Stream tests were conducted to determine the potential toxicity of a pulse of exposure as might occur when fire retardant chemical is rinsed from the watershed by rainfall. Two artificial 55-meter experimental streams were dosed with different concentrations of Fire-Trol?? GTS-R, or uncontaminated for a control. Replicate groups of fathead minnows were added to screened containers (10 fish per container) and exposed to retardant chemicals in the recirculating flow of the stream for up to 6 hours. Results and Discussion. Under field conditions toxicity of GTS-R only occurred in the presence of sunlight. When GTS-R was tested on sunny days, 100% mortality occurred. However, when tested during heavily overcast conditions, no mortality occurred. Conclusions. Lethal concentrations of cyanide were measured when GTS-R with YPS exposures were conducted under sunny conditions, but not under cloudy conditions, indicating that a minimum UV level is necessary to induce toxicity as well as the release of cyanide from YPS. The toxicity observed with GTS-R was likely associated with lethal concentrations of cyanide. Rainwater runoff following applications of this fire-retardant at the recommended rate could result in lethal concentrations in small ponds and streams receiving limited water flow under sunny conditions. Recommendations and Outlook. In addition to avoiding application to aquatic habitats, it is important to consider characteristics of the treated site including soil binding affinity and erosive properties.

  19. Environmental hormones and their impacts on sex differentiation in fathead minnows.

    PubMed

    Leet, Jessica K; Sassman, Stephen; Amberg, Jon J; Olmstead, Allen W; Lee, Linda S; Ankley, Gerald T; Sepúlveda, Maria S

    2015-01-01

    Runoff from lands fertilized with animal manure from concentrated animal feeding operations (CAFOs) is a source of hormones to surface water. In this study we tested the hypothesis that larval fathead minnows exposed to sex steroids singly or in a "typical" CAFO mixture during sex differentiation would respond with changes in the expression of a set of target genes, leading to gonadal abnormalities later in life. In the first experiment, a static daily-renewal system was used to expose larvae during the period of 10-20 days post-hatch (dph) to either 5 ng/L 17β-trenbolone (17β-TRB) or 5 ng/L 17α-ethinylestradiol (EE2). In a second experiment, fish were exposed from 0 to 45 dph in a flow-through system to a CAFO mixture composed of steroids and degradates (2-16 ng/L), atrazine and degradates (15-250 ng/L), and nitrate (3-11 mg/L). In the single hormone experiment, expression of genes involved in steroidogenesis (cyp19a, cyp17, and star) was decreased in females. In contrast, no differences in gene expression were observed in fish exposed to the CAFO mixture. However, the majority (84%) of treated males had testes containing an ovarian cavity, indicative of feminization, compared to 0% in the control males. Overall, our results show that: (1) changes in gene expression after single hormone exposures are sex-specific, with females more responsive than males; and (2) phenotypic alterations in testicular development can be elicited by a simulated "CAFO" mixture when fathead minnows are exposed during the first 45 days of development. More research is needed to further discern the complex response of fish to steroid mixtures, especially those associated with runoff from land-applied CAFO waste. PMID:25671225

  20. Isolation of the Fathead Minnow Nidovirus from Muskellunge Experiencing Lingering Mortality.

    PubMed

    Faisal, Mohamed; Baird, Ashley; Winters, Andrew D; Millard, Elena V; Marcquenski, Sue; Hsu, Hui-Min; Hennings, Ann; Bochsler, Phil; Standish, Isaac; Loch, Thomas P; Gunn, Michelle R; Warg, Janet

    2016-06-01

    In 2011, the Fathead Minnow nidovirus (FHMNV; Genus Bafinivirus, Family Coronaviridae, Order Nidovirales) was isolated from pond-raised juvenile Muskellunge Esox masquinongy suffering from lingering mortality at the Wild Rose Hatchery in Wild Rose, Wisconsin. Moribund Muskellunge exhibited tubular necrosis in the kidneys as well as multifocal coalescing necrotizing hepatitis. The FHMNV was also isolated from apparently healthy juvenile Muskellunge at the Wolf Lake State Fish Hatchery in Mattawan, Michigan. The identity of the two syncytia-forming viruses (designated MUS-WR and MUS-WL from Wild Rose Hatchery and Wolf Lake State Fish Hatchery, respectively) as strains of FHMNV was determined based on multiple-gene sequencing and phylogenetic analyses. The pathogenicity of the MUS-WL FHMNV strain was determined by experimentally infecting naive juvenile Muskellunge through intraperitoneal injection with two viral concentrations (63 and 6.3 × 10(3) TCID50/fish). Both doses resulted in 100% mortality in experimentally infected fish, which exhibited severely pale gills and petechial hemorrhaging in eyes, fins, and skin. Histopathological alterations in experimentally infected fish were observed mainly in the hematopoietic tissues in the form of focal areas of necrosis. Phylogenetic analysis of concatenated partial spike glycoprotein and helicase gene sequences revealed differences between the MUS-WL FHMNV, MUS-WR FHMNV, and two other FHMNV originally isolated from moribund Fathead Minnows Pimephales promelas including the index FHMNV strain (GU002364). Based on a partial helicase gene sequence, a reverse transcriptase PCR assay was developed that is specific to FHMNV. These results give evidence that the risks posed to Muskellunge by FHMNV should be taken seriously. Received May 1, 2015; accepted February 8, 2016. PMID:27230033

  1. Impairment of the reproductive potential of male fathead minnows by environmentally relevant exposures to 4-nonylphenolf

    USGS Publications Warehouse

    Schoenfuss, H.L.; Bartell, S.E.; Bistodeau, T.B.; Cediel, R.A.; Grove, K.J.; Zintek, L.; Lee, K.E.; Barber, L.B.

    2008-01-01

    The synthetic organic compound 4-nonylphenol (NP) has been detected in many human-impacted surface waters in North America. In this study, we examined the ability of NP to alter reproductive competence in male fathead minnows after a 28 day flow-through exposure in a range of environmentally relevant concentrations bracketing the U.S. Environmental Protection Agency toxicity-based NP chronic exposure criterion of 6.1 ??g NP/L. Exposure to NP at and above the EPA chronic exposure criterion resulted in an induction of plasma vitellogenin (VTG) within 14 days. However, 7 days after the cessation of exposure, VTG concentrations had dropped more than 50% and few males expressed VTG above the detection threshold. All of the morphological endpoints, including gonadosomatic index, hepatosomatic index, secondary sexual characters, and histopathology, were unaltered by all NP treatments. However, when NP-exposed male fish were allowed to compete with control males for access to nest sites and females, most treatments altered the reproductive competence of exposed males. At lower NP concentrations, exposed males out-competed control males, possibly by being primed through the estrogenic NP exposure in a fashion similar to priming by pheromones released from female fathead minnows. At higher NP exposure concentrations, this priming effect was negated by the adverse effects of the exposure and control males out-competed treated males. Results of this study indicate the complexity of endocrine disrupting effects and the need for multiple analysis levels to assess the effects of these compounds on aquatic organisms. ?? 2007 Elsevier B.V. All rights reserved.

  2. Effects of androstenedione exposure on fathead minnow (Pimephales promelas) reproduction and embryonic development.

    PubMed

    DeQuattro, Zachary A; Hemming, Jocelyn D C; Barry, Terence P

    2015-11-01

    High concentrations (300 ng/L) of androstenedione (A4) were identified in snowmelt runoff from fields fertilized with manure from livestock feeding operations in Wisconsin, USA. In fishes, A4 is an active androgen and substrate for biosynthesis of functional androgens (e.g., testosterone and 11-ketotestosterone) and estrogens (e.g., estradiol-17β). Thus, A4 has the potential to be a powerful endocrine disruptor. This hypothesis was tested by exposing reproductively mature fathead minnows to 0.0 ng/L, 4.5 ng/L, 74 ng/L, and 700 ng/L A4 for 26 d in a flow-through system. Various reproductive endpoints were measured including fecundity, fertilization success, secondary sexual characteristics, gonadosomatic index (GSI), and hepatic vitellogenin messenger RNA (mRNA) expression. In addition, fertilized embryos from the reproduction assay were used in an embryonic development assay to assess A4 effects on development and hatchability. In males, A4 significantly increased Vtg mRNA expression (estrogenic effect), significantly reduced GSI, and had no effect on tubercle expression (p = 0.067). In females, A4 induced tubercle development (androgenic effect) with no effects on GSI. Fecundity was not significantly impacted. Exposure to A4 had no effect on fertilization, embryonic development, or hatchability. These data indicate that exogenous A4, at environmentally relevant concentrations, can significantly modulate the reproductive physiology of the fathead minnows in a sex-specific manner and that A4 should be monitored as an endocrine disruptor.

  3. Influence of metal concentrations, percent salinity, and length of exposure on the metabolic rate of fathead minnows (Pimephales promelas).

    PubMed

    Pistole, David H; Peles, John D; Taylor, Kelly

    2008-07-01

    Understanding the effects of chemical toxicants on energetic processes is an important aspect of ecotoxicology. However, the influence of toxicant concentration and time of exposure on metabolism in aquatic organisms is still poorly understood. The purpose of this investigation was to determine the influence of increasing levels of three stressors (Cu, Cd, percent salinity) and exposure time (24 h and 96 h) on the metabolic rate of fathead minnows (Pimephales promelas). In all 24-h exposures, there existed a threshold concentration, above which metabolic rate decreased significantly compared to the control and lower concentrations. In contrast, the metabolic rate of fish exposed for 96 h increased significantly in all concentrations compared to fish from the control. We suggest fathead minnows exhibit a consistent pattern of metabolic response to stressors, regardless of the physiological mechanisms involved, and that this response differs as a function of time of exposure.

  4. Observed and modeled effects of pH on bioconcentration of diphenhydramine, a weakly basic pharmaceutical, in fathead minnows

    EPA Science Inventory

    Fathead minnows were exposed to diphenhydramine (DPH), a weakly basic pharmaceutical (pKa = 9.1), to examine pH effects on uptake and accumulation. Fish were exposed to 10 ìg/L DPH in water for up to 96 h at three nominal pH levels: 6.7, 7.7, and 8.7. In each case, an appa...

  5. Fathead minnow vitellogenin: Complementary DNA sequence and messenger RNA and protein expression after 17{beta}-estradiol treatment

    SciTech Connect

    Korte, J.J.; Kahl, M.D.; Jensen, K.M.; Pasha, M.S.; Parks, L.G.; LeBlanc, G.A.; Ankley, G.T.

    2000-04-01

    Induction of vitellogenin (VTG) in oviparous animals has been proposed as a sensitive indicator of environmental contaminants that activate the estrogen receptor. In the present study, a sensitive ribonuclease protection assay (RPA) for VTG messenger RNA (mRNA) was developed for the fathead minnow (Pimephales promelas), a species proposed for routine endocrine-disrupting chemical (EDC) screening. The utility of this method was compared with an enzyme-linked immunosorbent assay (ELISA) specific for fathead minnow VTG protein. Assessment of the two methods included kinetic characterization of the plasma VTG protein and hepatic VTG mRNA levels in male fathead minnows following intraperitoneal injections of 17{beta}-estradiol (E2) at two dose levels (0.5, 5.0 mg/kg). Initial plasma E2 concentrations were elevated in a dose-dependent manner but returned to normal levels within 2 d. Lover VTG mRNA was detected within 4 h, reached a maximum around 48 h, and returned to normal levels in about 6 d. Plasma VTG protein was detectable within 16 h of treatment reached maximum levels at about 72 h. and remained near these maximum levels for at least 18 d. While the RPA was about 1,000 times more sensitive than the ELISA, the ELISA appears superior for routine screening tests. The ELISA method is relatively simple to perform and, because males lack a clearance mechanism for VTG, the protein remains at relatively high concentrations in the plasma for an extended period of time. As part of the development of the RPA, the complementary DNA (cDNA) sequence for fathead minnow VTG was determined and the deduced amino acid sequence compared with VTG sequences for other fish species.

  6. Chronic toxicity of di-n-butyl and di-n-octyl phthalate to Daphnia magna and the fathead minnow

    SciTech Connect

    McCarthy, J.F.; Whitmore, D.K.

    1985-01-01

    The toxicities of di-n-butyl phthalate (DBP) and di-n-octyl phthalate (DOP) were assessed by measuring the effect of exposure to these compounds on the fecundity of Daphnia magna and on the hatching and survival of the early life stages of the fathead minnow Pimephales promelas. For D. magna, exposure to 1.8 mg/L DBP or 1.0 mg/L DOP caused a significant reduction in reproduction. Doses of 0.56 mg/L DBP or 0.32 mg/L DOP had no significant effect in decreasing reproduction. Survival of fathead minnow embryos was decreased by exposure to 1.8 mg/L DBP; none of the embryos exposed to this dose hatched successfully. Hatching and larval survival were affected by exposure to 1.0 mg/L DBP, but not to 0.56 mg/L. Exposure to DOP did not affect survival of either early embryos or larvae of the fathead minnow at doses up to 10 mg/L (the highest dose tested). Hatching of the embryos was significantly decreased at 10 mg/L, but not at 3.2 mg/L DOP. 26 references, 4 figures, 11 tables.

  7. Comparison of zebrafish (Danio rerio) and fathead minnow (Pimephales promelas) as test species in the Fish Sexual Development Test (FSDT).

    PubMed

    Holbech, Henrik; Kinnberg, Karin L; Brande-Lavridsen, Nanna; Bjerregaard, Poul; Petersen, Gitte I; Norrgren, Leif; Orn, Stefan; Braunbeck, Thomas; Baumann, Lisa; Bomke, Christiane; Dorgerloh, Michael; Bruns, Eric; Ruehl-Fehlert, Christine; Green, John W; Springer, Timothy A; Gourmelon, Anne

    2012-03-01

    Results are presented from a validation (with 5 laboratories) of the Fish Sexual Development Test (FSDT) developed to detect endocrine disrupters (EDs) and included in the OECD (Organisation for Economic Co-operation and Development) working program. The aromatase-inhibiting fungicide prochloraz was tested in zebrafish (Danio rerio) and fathead minnow (Pimephales promelas). The fish were exposed during sexual differentiation and development from 0 to 60 days post hatch (dph). After exposure, the vitellogenin (VTG) concentrations were quantified in head/tail homogenate and the sex ratio was determined (defined as female, male, intersex or undifferentiated). NOEC/LOEC and EC(x) designs were compared to optimize the test approach. Results show that both species are highly sensitive to prochloraz during sexual development. They respond by skewing of the sex ratio towards male phenotype and by a VTG decline in females. The NOEC/LOEC approach is preferred because sex ratio is difficult to analyze with a regression model. The mean NOEC/LOEC for prochloraz on the sex ratio was 43.3/134 μg/L and 101/293 μg/L for zebrafish and fathead minnow, respectively. The mean NOEC/LOEC on the decline in female VTG concentration was 65/110 μg/L and ~30/68 μg/L respectively. In conclusion, zebrafish and fathead minnow are suitable species in the FSDT and their sexual differentiation is equally labile to EDs. PMID:22115822

  8. Tissue lead concentration during chronic exposure of Pimephales promelas (fathead minnow) to lead nitrate in aquarium water.

    PubMed

    Spokas, Eric G; Spur, Bernd W; Smith, Holly; Kemp, Francis W; Bogden, John D

    2006-11-01

    The fathead minnow is a useful species for evaluating the toxicity of wastewater effluents. While this fish is widely used for "survival" studies of metal toxicity, little or no work has been done on the tissue distribution of metals in fathead minnows. To determine the distribution of tissue lead, aquarium studies were conducted for several weeks with fish maintained in soft synthetic freshwater. Lead- (II) nitrate was added to three aquaria attaining concentrations of 20-30 ppb (aquarium B), 100-140 ppb (aquarium C), and roughly 200 ppb (aquarium D). Results were compared to controls (aquarium A). During the initial week, the majority of aquarium D fish died, whereas few deaths occurred in the other groups. Lead accumulation was dose- and tissue-dependent, with highest uptake by the gills. Gill concentrations of aquarium D fish averaged about 4-fold higherthan in skeleton or skin and muscle. In vitro, lead (2.5-25 ppm) caused dose-dependent reductions in the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) in gills incubated in physiological buffer. These findings demonstrate that fathead minnow gills bind and accumulate waterborne lead rapidly and preferentially and raise the possibility that gill lipid peroxidation contributes to lead toxicity at low water hardness.

  9. Tissue Lead Concentration During Chronic Exposure of Pimephales promelas (Fathead Minnow) to Lead Nitrate in Aquarium Water

    PubMed Central

    Spokas, Eric G.; Spur, Bernd W.; Smith, Holly; Kemp, Francis W.; Bogden, John D.

    2008-01-01

    The fathead minnow is a useful species for evaluating the toxicity of wastewater effluents. While this fish is widely used for “survival” studies of metal toxicity, little or no work has been done on the tissue distribution of metals in fathead minnows. To determine the distribution of tissue lead, aquarium studies were conducted for several weeks with fish maintained in soft synthetic freshwater. Lead II nitrate was added to 3 aquaria attaining concentrations of 20 - 30 ppb (aquarium B); 100 - 140 ppb (aquarium C); and roughly 200 ppb (aquarium D). Results were compared to controls (aquarium A). During the initial week, the majority of aquarium D fish died, whereas few deaths occurred in the other groups. Lead accumulation was dose- and tissue-dependent, with highest uptake by the gills. Gill concentrations of aquarium D fish averaged about four-fold higher than in skeleton or skin and muscle. In vitro, lead (2.5 to 25 ppm) caused dose-dependent reductions in the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) in gills incubated in physiological buffer. These findings demonstrate that fathead minnow gills bind and accumulate waterborne lead rapidly and preferentially, and raise the possibility that gill lipid peroxidation contributes to lead toxicity at low water hardness. PMID:17144321

  10. EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

    SciTech Connect

    Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

    2012-05-01

    technical manuscript); (3) additional laboratory experimentation focused on the potential effects of long-term exposures to fly ash on fish survival and reproductive competence; and (4) a combined field and laboratory study examining the in vitro developmental success of embryos and larvae obtained from fish exposed in vivo for over two years to fly ash in the Emory and Clinch Rivers. These fish reproduction and early life-stage studies are being conducted in conjunction with a broader biological monitoring program administered by TVA that includes a field study of the condition of larval fish in the Emory and Clinch Rivers along with assessments of water quality, sediment composition, ecotoxicological studies, terrestrial wildlife studies, and human and ecological risk assessment. Information and data generated from these studies will provide direct input into risk assessment efforts and will also complement and help support other phases of the overall biomonitoring program. Fish eggs, in general, are known to be capable of concentrating heavy metals and other environmental contaminants from water-borne exposures during embryonic development (Jezierska and others 2009), and fathead minnow embryos in particular have been shown to concentrate methylmercury (Devlin 2006) as well as other chemical toxicants. This technical report focuses on the responses of fathead minnow embryos to simple contact exposures to fly ash in laboratory toxicity tests adapted from a standard fathead minnow (Pimephales promelas) 7-d embryo-larval survival and teratogenicity test (method 1001.0 in EPA 2002) with mortality, hatching success, and the incidences of developmental abnormalities as measured endpoints.

  11. Alternative methods for toxicity assessments in fish: comparison of the fish embryo toxicity and the larval growth and survival tests in zebrafish and fathead minnows.

    PubMed

    Jeffries, Marlo K Sellin; Stultz, Amy E; Smith, Austin W; Rawlings, Jane M; Belanger, Scott E; Oris, James T

    2014-11-01

    An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative, and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. In the present study, the performances of the FET test and the larval growth and survival (LGS; a standard toxicity testing method) test in zebrafish and fathead minnows were evaluated. This required that testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and that the performance of these testing strategies be evaluated by comparing the median lethal concentrations of 2 reference toxicants, 3,4-dicholoraniline and ammonia, obtained via each of the test types. The results showed that procedures for the zebrafish FET test can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for 3,4-dicholoraniline but not ammonia; therefore, conclusions regarding which test types offer the least or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and that further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy.

  12. Metabolic and reproductive effects of relatively low concentrations of beclomethasone dipropionate, a synthetic glucocorticoid, on fathead minnows.

    PubMed

    Kugathas, Subramaniam; Runnalls, Tamsin J; Sumpter, John P

    2013-08-20

    Pharmaceuticals present in the aquatic environment could adversely affect aquatic organisms. Synthetic glucocorticoids (GC) are used in large quantities as anti-inflammatory drugs and have been reported to be present in river water. In order to assess the impact of environmental concentrations of GCs, an in vivo experiment was conducted with adult fathead minnows. Fish were exposed to 0.1 μg/L, 1 μg/L, or 10 μg/L beclomethasone dipropionate (BCMD) via a flow-through system over a period of 21 days. Similar duplicate tanks served as control, with no chemical added. There was a concentration-related increase in plasma glucose concentration and a decrease in blood lymphocyte count. Induction of male secondary sexual characters and a decreasing trend in plasma vitellogenin (Vtg) concentrations in female fish were observed with increasing exposure concentration of BCMD. Expression profiles of selected genes (phosphoenolpyruvate carboxykinase - PEPCK, glucocorticoid receptor - GR, and Vtg) in liver also demonstrated concentration-related effects at all three tested concentrations. The results suggest that GCs could cause effects in lower micrograms per liter concentrations that could be environmentally relevant for total GCs present in the environment. Therefore, studies to determine the environmental concentrations of GCs and no effect concentrations are needed to assess if GCs pose a risk to the aquatic environment. PMID:23869980

  13. Low level exposure to the flame retardant BDE-209 reduces thyroid hormone levels and disrupts thyroid signaling in fathead minnows

    PubMed Central

    Noyes, Pamela D.; Lema, Sean C.; Macaulay, Laura J.; Douglas, Nora K.; Stapleton, Heather M.

    2013-01-01

    Polybrominated diphenyl ether (PBDE) flame retardants have been shown to disrupt thyroid hormone regulation, neurodevelopment, and reproduction in some animals. However, effects of the most heavily used PBDE, decabromodiphenyl ether (BDE-209), on thyroid functioning remain unclear. This study examined low-dose effects of BDE-209 on thyroid hormone levels and signaling in fathead minnows. Adult males received dietary exposures of BDE-209 at a low dose (~3 ng/g bw-day) and high dose (~300 ng/g bw-day) for 28 days followed by a 14-day depuration to evaluate recovery. Compared to controls, fish exposed to the low dose for 28 days experienced a 53% and 46% decline in circulating total thyroxine (TT4) and 3,5,3'-triiodothyronine (TT3), respectively, while TT4 and TT3 deficits at the high dose were 59% and 62%. Brain deiodinase activity (T4-ORD) was reduced by ~65% at both doses. BDE-209 elevated the relative mRNA expression of genes encoding deiodinases, nuclear thyroid receptors, and membrane transporters in the brain and liver in patterns that varied with time and dose, likely in compensation to hypothyroidism. Declines in the gonadal-somatic index (GSI) and increased mortality were also measured. Effects at the low dose were consistent with the high dose, suggesting non-linear relationships between BDE-209 exposures and thyroid dysfunction. PMID:23899252

  14. Evaluation of acute copper toxicity to larval fathead minnows (Pimephales promelas) in soft surface waters.

    PubMed

    Van Genderen, Eric J; Ryan, Adam C; Tomasso, Joseph R; Klaine, Stephen J

    2005-02-01

    The hardness-based regulatory approach for Cu prescribes an extrapolation of the toxicity-versus-hardness relationship to low hardness (< or =50 mg/L as CaCO3). Hence, the objective of the present research was to evaluate the influences of water quality on acute Cu toxicity to larval fathead minnow (Pimephales promelas) in low-hardness surface waters. Seasonal water sampling was conducted at 24 sites throughout South Carolina, USA, to determine the site-specific influences of soft surface-water conditions on acute Cu toxicity. Concurrent toxicity tests in laboratory water, matched for hardness and alkalinity (modified method), also were conducted to allow calculation of water-effect ratios (WERs). In addition, tests were conducted at recommended hardness levels (recommended method) for comparison of WER methodology in soft water. Surface-water conditions (average+/-standard deviation, n = 53) were hardness of 16+/-8 mg/L as CaCO3, alkalinity of 18+/-11 mg/L as CaCO3, and dissolved organic carbon of 6+/-4 mg/L. Dissolved Cu 48-h median lethal concentration (LC50) values varied nearly 45-fold across the dataset and greater than four-fold at individual sites. Spatial (p < 0.0001) and seasonal (p = 0.026) differences among LC50 values were determined for eight sites that had multiple toxicity results for one year. All modified WERs were greater than 1.0, suggesting that the site waters were more protective of Cu toxicity than the matched laboratory water. Some WERs generated using recommended methods were less than 1.0, suggesting limited site-specific protection. Based on these observations, extrapolation of the hardness-based equation for Cu at 50 mg/L or less as CaCO3 would adequately protect fathead minnow populations in soft surface waters. The WER results presented here demonstrate the inconsistency between hardness-based criteria and the methodology for deriving site-specific water-quality criteria in low-hardness waters.

  15. Development and validation of a direct homologous quantitative sandwich ELISA for fathead minnow (Pimephales promelas) vitellogenin.

    PubMed

    Eidem, Janne K; Kleivdal, Hans; Kroll, Kevin; Denslow, Nancy; van Aerle, Ronny; Tyler, Charles; Panter, Grace; Hutchinson, Tom; Goksøyr, Anders

    2006-06-15

    Vitellogenin (Vtg) is an established and sensitive endpoint for analysis of exposure to (anti-)oestrogens and their mimics in fish [Sumpter, J.P., 1995. Feminized responses in fish to environmental estrogens. Toxicol. Lett. 82, 737-742; Arukwe, A., Goksøyr, A., 2003. Eggshell and egg yolk proteins in fish: hepatic proteins for the next generation: oogenetic, population, and evolutionary implications of endocrine disruption. Comp. Hepatol. 2, 4. ]. In some instances, links have been drawn between high level induction of Vtg and adverse health effects in fish [Herman, R.L., Kincaide, H.L., 1988. Pathological effects of orally administered estradiol to rainbow trout. Aquaculture 72, 165-172; Schwaiger, J., Spieser, O.H., Bauer, C., Ferling, H., Mallow, U., Kalbfus, W., Negele, R.D., 2000. Chronic toxicity of nonylphenol and ethinyloestraiol: haematological and histopathological effects in juvenile common carp (Cyprinus carpio). Aquat. Toxicol. 51, 69-78]. The widespread use of Vtg as a biomarker has led to the development of a variety of assays to quantitatively measure Vtg concentrations in tissue samples from fish, and hence a need for a standardization of the performance criteria and validation of such assays [Goksøyr, A., Eidem, J.K., Kristiansen, S.I., Nilsen, B.M., 2003. On the need for a standardized set-up for validation studies of fish vitellogenin assays as an endpoint in endocrine disruptor testing and screening-a proposal. ]. One of the most popular test fish species for assessing chemical effects is the fathead minnow (Pimephales promelas), which is now used widely for studies into endocrine disruption [Panter, G.H., Hutchinson, T.H., Lange, R., Lye, C.M., Sumpter, J.P., Zerulla, M., Tyler, C.R., 2002. Utility of a juvenile fathead minnow screening assay for detecting (anti)estrogenic substances. Environ. Toxicol. Chem. 21, 319-326; Hutchinson, T.H., Yokota, H., Hagino, S., Ozato, K., 2003. Development of fish tests for endocrine disruptors. Pure Appl

  16. Effects of zebra mussel (Dreissena polymorpha) density on the survival and growth of juvenile fathead minnows (Pimephales promelas): Implications for North American river fishes

    USGS Publications Warehouse

    Jennings, Cecil A.

    1996-01-01

    I used replicated 37.8 1 aquaria in a factorial design (four densities of zebra mussel, Dreissena polymorpha; two hydrologic regimes) to determine if the survival or growth of juvenile fathead minnows (Pimephales promelas) was affected by the density of zebra mussel or by the retention time of the test system. None of the fathead minnows died during the 30-d experiment. However, growth of fathead minnows was lower (P0.05). These laboratory results suggest that juvenile fish survival will not be affected by low to moderate densities of mussels (0-3000 m super(-2)) but fish growth might be adversely affected at moderate densities of mussels (e.g., 3000 m super(-2)).

  17. Adaptation to fluoranthene exposure in a laboratory population of fathead minnows

    SciTech Connect

    Diamond, S.A.; Oris, J.T.; Guttman, S.I.

    1995-08-01

    Tolerance of toxicant exposure is common in polluted sites in nature. However, in most cases, the processes underlying tolerance acquisition are not well understood. In the case of exposure to polycyclic aromatic hydrocarbons (PAHs) in particular, reports are lacking on the capacity for tolerance acquisition. To evaluate the potential for adaptation to this class of contaminants the authors exposed a large laboratory population of fathead minnows to fluoranthene, commonly a major constituent of PAH contamination. The exposure concentration chosen did not cause mortality but was sufficient to diminish reproductive capacity in exposed breeding fish relative to a control population. This level of exposure also significantly diminished hatching success and larval survivorship in the exposed population. The estimated value of selection against susceptibility (the product of all assessments of effect) was 0.67. Tests for tolerance acquisition included comparative larval 96-h LC50 determinations, and comparative juvenile median time to death (LT50) determinations. Enhanced tolerance was not apparent in the LC50 determinations, although an examination of the concentration-response distribution suggested an adverse effect due to egg and larval exposure to fluoranthene prior to the test. In contrast, results of the comparative LT50 determination indicated that the exposed population was approximately 30% more tolerant, relative to the control population, when exposed to an acutely toxic concentration of fluoranthene. These results suggest that tolerance to PAH exposure can occur in nature and that this population-level response needs to be examined relative to other recognized effects in PAH-contaminated areas.

  18. Effects of the insecticide fipronil on reproductive endocrinology in the fathead minnow.

    PubMed

    Bencic, David C; Villeneuve, Daniel L; Biales, Adam D; Blake, Lindsey; Durhan, Elizabeth J; Jensen, Kathleen M; Kahl, Michael D; Makynen, Elizabeth A; Martinović-Weigelt, Dalma; Ankley, Gerald T

    2013-08-01

    Gamma-aminobutyric acid (GABA) and GABA receptors play an important role in neuroendocrine regulation in fish. Disruption of the GABAergic system by environmental contaminants could interfere with normal regulation of the hypothalamic-pituitary-gonadal axis, leading to impaired fish reproduction. The present study used a 21-d fathead minnow (Pimephales promelas) reproduction assay to investigate the reproductive toxicity of fipronil (FIP), a broad-spectrum phenylpyrazole insecticide that acts as a noncompetitive blocker of GABA receptor-gated chloride channels. Continuous exposure up to 5 µg FIP/L had no significant effect on most of the endpoints measured, including fecundity, secondary sexual characteristics, plasma steroid and vitellogenin concentrations, ex vivo steroid production, and targeted gene expression in gonads or brain. The gonad mass, gonadosomatic index, and histological stage of the gonad were all significantly different in females exposed to 0.5 µg FIP/L compared with those exposed to 5.0 µg FIP/L; however, there were no other significant effects on these measurements in the controls or any of the other treatments in either males and females. Overall, the results do not support a hypothesized adverse outcome pathway linking FIP antagonism of the GABA receptor(s) to reproductive impairment in fish.

  19. Quantitative structure-activity relationships (QSAR) for nitroaromatics to fathead minnow

    SciTech Connect

    Lang, P.Z.; Lu, G.H.; Ma, X.F.

    1994-12-31

    QSAR was studied with the reported semi-flow-through 96 h-LC{sub 50} values for fathead minnow using six physicochemical descriptors. The parameters used include {sup 1}X{sup v}, {sup 1}K{alpha}, {Sigma}{sigma}-, log P, I and E{sub LUMO}. The values of I were cited from literature (Hall et al., 1989). E{sub LUMO} was used instead of the reported E{sub 1/2}. E{sub LUMO} of 51 compounds was predicted by CNDO/2. By regression, a QSAR equation was obtained: {minus}log LC{sub 50} = 3.514 + 0.416 I + 0.344 {Sigma}{sigma}- (n = 35, r = 0.965, s = 0.194). The nitroaromatics include dinitrobenzenes, trinitrobenzenes, trinitrotoluenes and some substituted benzenes containing one or two -NO{sub 2} and one of -CH{sub 3}, -Cl, -F, -OH, -NH{sub 2} or -OCH{sub 3}. The QSAR equation was used to estimate LC{sub 50} for 16 nitroaromatics. Inferred from the obtained equation, of the compounds studied here, the dinitro compounds (their I and {Sigma}{sigma}- are all high) are reactive and the mononitro compounds are less reactive or non-reactive.

  20. Waterborne lead affects circadian variations of brain neurotransmitters in fathead minnows

    SciTech Connect

    Spieler, R.E.; Russo, A.C.; Weber, D.N.

    1995-09-01

    Lead is a potent neurotoxin affecting brain levels of a number of vertebrate neurotransmitters. Reports on these effects are, however, not consistent either among or within species. For example, with lead-intoxicated rats there are reports of decreased acetylcholine (ACh) release and decreased ACh brain levels as well as reports of increased levels or no change in levels. Also, with rats there are reports of increased levels, decreased levels, or no change in brain catecholamines, with lead producing similar changes in both norephinephrine (NE) and dopamine (DA) in some cases and differences in response between the two in others. Although most early reports dealt with whole brain levels, reports on neurotransmitter levels in specific brain regions can be equally conflicting. Similar sorts of discrepancies exist among studies with fishes. Much of the variation among studies on lead effects on neurotransmitters is, no doubt, due to differences among the studies in variables such as: species, age, dosage and duration, route of administration. However, lead can apparently affect circadian locomotor rhythms of both rats and fishes. Therefore, another possible cause for the variation among studies is that there is an interaction among dosage, sampling time and endogenous rhythms. A lead-produced phase shift or disruption in endogenous neurotransmitter rhythms could in turn elicit a host of varying results and interpretations depending on the circadian time of sampling. We elected to examine this possibility in the fathead minnow, Pimephales promelas, a freshwater species widely used for toxicity studies. 15 refs., 3 figs.

  1. Teratogenic effects of zinc on embryo-larval stages of the fathead minnow

    SciTech Connect

    Ramey, B.A.

    1988-10-01

    The effects of zinc on embryos and larvae of the fathead minnow were studied using standard 8-day embryo-larval bioassay techniques to determine if there was a period in embryonic development which would be the most sensitive. Virtually all larvae at all stages were abnormal at 1.0 mg Zn/L, displaying edema and curvature of the vertebral axis. Although LC/sub 50/ values for the five developmental stages ranged from 0.13 to 0.62 mg/L, there was not a significantly most sensitive stage. When larvae were exposed to 1.0 mg Zn/L only during the 96 hour after hatching, all animals were anomalous. If zinc exposure occurred only during the prehatch period and larvae were placed in control water posthatch, only 5% of the larvae were abnormal. At sublethal concentrations the chorion may impart a protective mechanism to the teratogenic effects of zinc, but this protection may be lost after hatching.

  2. Assessment of swimming activity as an indicator of sublethal toxicity to the fathead minnow

    SciTech Connect

    Hovland, D.N. Jr.

    1994-12-31

    A simple, sensitive acute-bioassay was developed that looks at spontaneous swimming activity as an indicator of sublethal effect due to toxic insult. Although a large amount of work has been done validating aquatic behavior testing, there are still no standardized testing procedures or protocols for their use in assessing environmental impact of pollutants. Attempts were made in this research to develop a behavioral test that was objective and provided a basis for standardization and use in effluent testing. Tests were performed using copper sulfate and zinc sulfate as reference toxicants. Testing procedures involved 24-hour exposures to a range of toxicant concentrations with 12 fathead minnows (Pimephales promelas) per concentration. Upon completion, during a 2-minute testing period in a cylindrical aquarium, individual fish were videotaped from above, then timed later to determine actual time in swimming motion, which was averaged for each concentration group. Results demonstrate the sensitivity of the test, as significant differences from controls in swimming activity were observed at concentrations of copper sulfate as low as 1.3 ppb and zinc sulfate as low as 3.5 ppb, both well below Federal criteria for water quality. It is hoped that further research will demonstrate the utility of sublethal, behavioral toxicity tests, and that these tests will be integrated into the battery of toxicity testing procedures currently used by regulatory agencies.

  3. High diet overlap between native small-bodied fishes and nonnative fathead minnow in the Colorado River, Grand Canyon, Arizona

    USGS Publications Warehouse

    Seegert, Sarah E. Zahn; Rosi-Marshall, Emma J.; Baxter, Colden V.; Kennedy, Theodore A.; Hall, Robert O.; Cross, Wyatt F.

    2014-01-01

    River regulation may mediate the interactions among native and nonnative species, potentially favoring nonnative species and contributing to the decline of native populations. We examined food resource use and diet overlap among small-bodied fishes in the Grand Canyon section of the Colorado River as a first step in evaluating potential resource competition. We compared the diets of the predominant small-bodied fishes (native Speckled Dace Rhinichthys osculus, juvenile Flannelmouth Sucker Catostomus latipinnis, and juvenile Bluehead Sucker C. discobolus, and nonnative Fathead Minnow Pimephales promelas) across seasons at four sites downstream of Glen Canyon Dam using nonmetric multidimensional scaling and Schoener's similarity index. The diets of these fishes included diatoms, amorphous detritus, aquatic invertebrates (especially simuliid and chironomid larvae), terrestrial invertebrates, and terrestrial vegetation. Diets varied with season and were affected by high turbidity. Fish consumed more amorphous detritus and terrestrial vegetation during the summer monsoon season (July–September), when turbidity was higher. The diets of all species overlapped, but there was large variation in the degree of overlap. The diets of juvenile suckers and Fathead Minnows were most similar, while Speckled Dace had relatively distinct diets. The differences took the form of higher proportions of diatoms and amorphous detritus in the diets of Bluehead Suckers and Fathead Minnows and higher proportions of simuliids and chironomids in those of Speckled Dace. If food resources are or become limiting, diet overlap suggests that competition may occur among native and nonnative species, which could have implications for the population dynamics of these fishes and for the management of the Colorado River ecosystem in Grand Canyon.

  4. Transcription of key genes regulating gonadal steroidogenesis in control and ketoconazole- or vinclozolin-exposed fathead minnows.

    PubMed

    Villeneuve, Daniel L; Blake, Lindsey S; Brodin, Jeffrey D; Greene, Katie J; Knoebl, Iris; Miracle, Ann L; Martinovic, Dalma; Ankley, Gerald T

    2007-08-01

    This study evaluated changes in the expression of steroidogenesis-related genes in male fathead minnows exposed to ketoconazole (KTC) or vinclozolin (VZ) for 21 days. The aim was to evaluate links between molecular changes and higher level outcomes after exposure to endocrine-active chemicals (EACs) with different modes of action. To aid our analysis and interpretation of EAC-related effects, we first examined variation in the relative abundance of steroidogenesis-related gene transcripts in the gonads of male and female fathead minnows as a function of age, gonad development, and spawning status, independent of EAC exposure. Gonadal expression of several genes varied with age and/or gonadal somatic index in either males or females. However, with the exception of aromatase, steroidogenesis-related gene expression did not vary with spawning status. Following the baseline experiments, expression of the selected genes in male fathead minnows exposed to KTC or VZ was evaluated in the context of effects observed at higher levels of organization. Exposure to KTC elicited changes in gene transcription that were consistent with an apparent compensatory response to the chemical's anticipated direct inhibition of steroidogenic enzyme activity. Exposure to VZ, an antiandrogen expected to indirectly impact steroidogenesis, increased pituitary expression of follicle-stimulating hormone beta-subunit as well as testis expression of 20beta-hydroxysteroid dehydrogenase and luteinizing hormone receptor transcripts. Results of this study contribute to ongoing research aimed at understanding responses of the teleost hypothalamic-pituitary-gonadal axis to different types of EACs and how changes in molecular endpoints translate into apical outcomes reflective of either adverse effect or compensation.

  5. Natural Variation in Fish Transcriptomes: Comparative Analysis of the Fathead Minnow (Pimephales promelas) and Zebrafish (Danio rerio)

    PubMed Central

    Wang, Rong-Lin; Bencic, David C.; Garcia-Reyero, Natàlia; Perkins, Edward J.; Villeneuve, Daniel L.; Ankley, Gerald T.; Biales, Adam D.

    2014-01-01

    Fathead minnow and zebrafish are among the most intensively studied fish species in environmental toxicogenomics. To aid the assessment and interpretation of subtle transcriptomic effects from treatment conditions of interest, better characterization and understanding are needed for natural variation in gene expression among fish individuals from lab cultures. Leveraging the transcriptomics data from a number of our toxicogenomics studies conducted over the years, we conducted a meta-analysis of nearly 600 microarrays generated from the ovary tissue of untreated, reproductively mature fathead minnow and zebrafish samples. As expected, there was considerable batch-to-batch transcriptomic variation; this “batch-effect” appeared to differentially impact subsets of fish transcriptomes in a nonsystematic way. Temporally more closely spaced batches tended to share a greater transcriptomic similarity among one another. The overall level of within-batch variation was quite low in fish ovary tissue, making it a suitable system for studying chemical stressors with subtle biological effects. The observed differences in the within-batch variability of gene expression, at the levels of both individual genes and pathways, were probably both technical and biological. This suggests that biological interpretation and prioritization of genes and pathways targeted by experimental conditions should take into account both their intrinsic variability and the size of induced transcriptional changes. There was significant conservation of both the genomes and transcriptomes between fathead minnow and zebrafish. The high degree of conservation offers promising opportunities in not only studying fish molecular responses to environmental stressors by a comparative biology approach, but also effective sharing of a large amount of existing public transcriptomics data for developing toxicogenomics applications. PMID:25493933

  6. Transcription of key genes regulating gonadal steroidogenesis in control and ketoconazole- or vinclozolin-exposed fathead minnows

    SciTech Connect

    Villeneuve, Daniel L.; Blake, Lindsey S.; Brodin, Jeffrey; Greene, Katie J.; Knoebl, Iris; Miracle, Ann L.; Martinovic, Dalma; Ankley, Gerald T.

    2007-08-01

    This study evaluated changes in the expression of steroidogenesis-related genes in male fathead minnows exposed to ketoconazole (KTC) or vinclozolin (VZ) for 21 days. The aim was to evaluate links between molecular changes and higher level outcomes after exposure to endocrine-active chemicals (EACs) with different modes of action. To aid our analysis and interpretation of EAC-related effects, we first examined variation in the relative abundance of steroidogenesis-related gene transcripts in the gonads of male and female fathead minnows as a function of age, gonad development, and spawning status, independent of EAC exposure. Gonadal expression of several genes varied with age and/or gonadal somatic index in either males or females. However, with the exception of aromatase, steroidogenesis-related gene expression did not vary with spawning status. Following the baseline experiments, expression of the selected genes in male fathead minnows exposed to KTC or VZ was evaluated in the context of effects observed at higher levels of organization. Exposure to KTC elicited changes in gene transcription that were consistent with an apparent compensatory response to the chemical's anticipated direct inhibition of steroidogenic enzyme activity. Exposure to VZ, an antiandrogen expected to indirectly impact steroidogenesis, increased pituitary expression of follicle-stimulating hormone beta-subunit as well as testis expression of 20beta-hydroxysteroid dehydrogenase and luteinizing hormone receptor transcripts. Results of this study contribute to ongoing research aimed at understanding responses of the teleost hypothalamic-pituitary-gonadal axis to different types of EACs and how changes in molecular endpoints translate into apical outcomes reflective of either adverse effect or compensation.

  7. Fishy Aroma of Social Status: Urinary Chemo-Signalling of Territoriality in Male Fathead Minnows (Pimephales promelas)

    PubMed Central

    Martinovic-Weigelt, Dalma; Ekman, Drew R.; Villeneuve, Daniel L.; James, Channing M.; Teng, Quincy; Collette, Timothy W.; Ankley, Gerald T.

    2012-01-01

    Chemical structures of several urinary reproductive pheromones in fish have been identified, and their role in the chemical communication of reproductive condition is well characterized. On the contrary, the role of chemical communication in signalling of social/territorial status in fish is poorly understood. Fathead minnows are an example of a fish species whose life history traits appear conducive to evolution of chemical communication systems that confer information about social/territorial status. Male reproduction in this species is dependent upon their ability to acquire and defend a high quality nesting territory, and to attract a female to the nest. We hypothesized that fathead minnow males use visual and urine-derived chemical cues to signal territorial status. To test this hypothesis, effects of territorial acquisition on male-specific secondary sex characteristics (SSCs) and urine volumes were first assessed. Second, frequencies of male urination in varying social contexts were examined. Finally, nuclear magnetic resonance-based metabolomics was used to identify urinary metabolites that were differentially excreted in the urine of territorial versus non-territorial males. The expression of SSCs, sperm, and urine volumes increased with territory acquisition, and either remained unchanged or decreased in non-territorial males. Frequency of male urination increased significantly in the presence of females (but not males), suggesting that females are the main target of the urinary signals. Territorial and non-territorial males had distinct urinary metabolomic profiles. An unforeseen finding was that one could discern future territorial status of males, based on their initial metabolomic profiles. Bile acids and volatile amines were identified as potential chemical signals of social status in the fathead minnow. The finding that trimethylamine (a fishy smelling volatile amine) may be a social cue is particularly interesting, because it is known to bind trace

  8. Fishy aroma of social status: urinary chemo-signalling of territoriality in male fathead minnows (Pimephales promelas).

    PubMed

    Martinovic-Weigelt, Dalma; Ekman, Drew R; Villeneuve, Daniel L; James, Channing M; Teng, Quincy; Collette, Timothy W; Ankley, Gerald T

    2012-01-01

    Chemical structures of several urinary reproductive pheromones in fish have been identified, and their role in the chemical communication of reproductive condition is well characterized. On the contrary, the role of chemical communication in signalling of social/territorial status in fish is poorly understood. Fathead minnows are an example of a fish species whose life history traits appear conducive to evolution of chemical communication systems that confer information about social/territorial status. Male reproduction in this species is dependent upon their ability to acquire and defend a high quality nesting territory, and to attract a female to the nest. We hypothesized that fathead minnow males use visual and urine-derived chemical cues to signal territorial status. To test this hypothesis, effects of territorial acquisition on male-specific secondary sex characteristics (SSCs) and urine volumes were first assessed. Second, frequencies of male urination in varying social contexts were examined. Finally, nuclear magnetic resonance-based metabolomics was used to identify urinary metabolites that were differentially excreted in the urine of territorial versus non-territorial males. The expression of SSCs, sperm, and urine volumes increased with territory acquisition, and either remained unchanged or decreased in non-territorial males. Frequency of male urination increased significantly in the presence of females (but not males), suggesting that females are the main target of the urinary signals. Territorial and non-territorial males had distinct urinary metabolomic profiles. An unforeseen finding was that one could discern future territorial status of males, based on their initial metabolomic profiles. Bile acids and volatile amines were identified as potential chemical signals of social status in the fathead minnow. The finding that trimethylamine (a fishy smelling volatile amine) may be a social cue is particularly interesting, because it is known to bind trace

  9. Effects of chloride, calcium, and dissolved organic carbon on silver toxicity: Comparison between rainbow tout and fathead minnows

    SciTech Connect

    Bury, N.R.; Galvez, F.; Wood, C.M.

    1999-01-01

    The effects of independently altering chloride, calcium, and dissolved organic carbon (DOC) on the toxicity of silver were compared between rainbow trout (Oncorhynchus mykiss) and fathead minnows (Pimephales promelas). The 96-h median lethal concentration toxicity tests for both species were performed under the same conditions, within the same containers. In addition, the effect of altering [Cl{sup {minus}}] on silver-induced perturbations to body Na{sup +} influx and gill silver load was studied. Toxicity tests were conducted in synthetic soft water (50 {micro}M Na{sup +}, 50 {micro}M Cl{sup {minus}}, 50 {micro}M Ca{sup 2+}, 0.3 mg DOC/L). The [Cl{sup {minus}}], [Ca{sup 2+}], and [DOC] were adjusted by the addition of NaCl, CaNO{sub 3}, or humic acid, respectively. On the basis of total silver, increasing [Cl{sup {minus}}] over a range of 50 {micro}M to 1,500 {micro}M resulted in a 4.3-fold increase in the 96-h LC50 values (decrease in toxicity) for rainbow trout, but did not significantly affect the 96-h LC50 values for fathead minnows. Increasing water [Ca{sup 2+}] (from 50 to 2,000 {micro}M) had only a small influence on the 96-h LC50 values in both species. If the 96-h LC50 values are calculated on the basis of ionic silver, Ag{sup +}, then, in the case of rainbow trout, toxicity correlates to Ag{sup +}. However, this correlation does not exist for fathead minnows. Increasing [Cl{sup {minus}}] did not affect the degree of perturbation of Na{sup +} influx during acute exposure (first 4 h) to 8 {micro}g Ag/L in either species, nor did it affect the whole-body silver uptake rates, but it did reduce the gill silver load. These results demonstrate that differences exist in the way in which water chemistry ameliorates silver toxicity between rainbow trout and fathead minnows.

  10. Effects of acid and aluminum on swim bladder development and yolk absorption in the fathead minnow, pimephales promelas, (journal version)

    SciTech Connect

    Leino, R.L.; McCormick, J.H.; Jensen, K.M.

    1988-05-01

    Thirty-day old fathead minnows were raised to maturity and spawning in a laboratory flow-through system using softened water at various pH and Al levels. Successful spawnings were reduced by more than 85% at pH 6.0, 5.5-25 microg/L Al+3, and 5.5, and absent in all pH 5.2 treatments. Hatching success, larval survival, swim bladder development and yolk absorption were reduced or abnormal when spawning did occur at lower pHs.

  11. Do fathead minnows, Pimephales promelas Rafinesque, alter their club cell investment in responses to variable risk of infection from Saprolegnia?

    PubMed

    Pollock, R J; Pollock, M S; Ferrari, M C O; Kaminskyj, S G W; Chivers, D P

    2012-04-01

    Fish in the Superorder Ostariophysi possess large epidermal club cells that release chemical cues warning nearby conspecifics of danger. Despite the long-held assumption that such club cells evolved under the selective force of predation, recent studies demonstrated that predation has no effect on club cell investment. Rather, club cells have an immune function and cell production may be stimulated by skin-penetrating pathogens and parasites. The current work investigates whether fathead minnows, Pimephales promelas, alter their club cell characteristics based on variation in infection risk. In a 2 × 3 design, we exposed minnows to infective cysts of two oomycete species (Saprolegnia ferax and S. parasitica) at three different concentrations (2, 20 or 200 cysts L(-1)). Club cell characteristics (number and size) were quantified 12 days after exposure. Saprolegnia parasitica is thought to be more pathogenic than S. ferax, hence we predicted greater club cell investment and a larger turnover rate of cells by minnows exposed to S. parasitica than S. ferax. We also predicted that minnows exposed to higher numbers of cysts should invest more in club cells and have a higher turnover rate of cells. We found no difference in club cell density or size between fish exposed to the two Saprolegnia species; however, fish exposed to high concentrations of pathogens had smaller club cells than those exposed to low concentrations, indicating a higher rate of turnover of cells in the epidermis. PMID:22313366

  12. Toxicogenomics of water chemistry influence on chronic lead exposure to the fathead minnow (Pimephales promelas).

    PubMed

    Mager, Edward M; Wintz, Henri; Vulpe, Chris D; Brix, Kevin V; Grosell, Martin

    2008-05-01

    Establishment of water quality criteria (WQC), intended to protect aquatic life, continues to rely principally on water hardness (i.e. Ca(2+)) for lead (Pb) despite growing evidence that other chemical parameters also strongly influence toxicity. To more clearly define the water chemistry parameters mediating Pb toxicity, we evaluated the effects of hardness as CaSO(4) and dissolved organic carbon (DOC) as humic acid during chronic (150 days) exposures to the fathead minnow. Measured Pb concentrations ranged from 157+/-5 nM (33+/-1 microg/L) Pb in base water to 177+/-7 (37+/-1 microg/L) and 187+/-7 nM (39+/-1 microg/L) Pb in CaSO(4)- or HA-supplemented water, respectively. Fish were collected at 2, 4, 10, 30, 63, 90 and 150 days of exposure. Traditional toxicological endpoints were examined alongside gene transcription analyses to help clarify the underlying mechanisms of Pb toxicity and to identify candidate molecular markers that might ultimately serve as robust indicators of exposure and effect. Addition of CaSO(4) did not prevent whole body Pb accumulation whereas DOC afforded strong protection (about half the amount accumulated by fish in base water) suggesting that current, hardness-based WQC are likely inaccurate for predicting chronic Pb effects in aquatic systems. Custom-made microarrays were co-hybridized with base water samples+/-Pb up to the 30 days time point. Quantitative PCR was employed to verify gene transcription responses and to extend analysis to the CaSO(4) and HA treatments and the 150 days time point. Identification of four genes by microarray analysis revealed clear Pb-induced responses over time: glucose-6-phosphate dehydrogenase, glutathione-S-transferase, ferritin and beta-globin. Results obtained by qPCR were in strong agreement with microarray data by regression analysis (r(2)=0.82, slope=1.28). The associated pathways implicated herein for these genes provide further evidence supporting roles for anemia and neurological disorders in

  13. Toxicogenomics of water chemistry influence on chronic lead exposure to the fathead minnow (Pimephales promelas).

    PubMed

    Mager, Edward M; Wintz, Henri; Vulpe, Chris D; Brix, Kevin V; Grosell, Martin

    2008-05-01

    Establishment of water quality criteria (WQC), intended to protect aquatic life, continues to rely principally on water hardness (i.e. Ca(2+)) for lead (Pb) despite growing evidence that other chemical parameters also strongly influence toxicity. To more clearly define the water chemistry parameters mediating Pb toxicity, we evaluated the effects of hardness as CaSO(4) and dissolved organic carbon (DOC) as humic acid during chronic (150 days) exposures to the fathead minnow. Measured Pb concentrations ranged from 157+/-5 nM (33+/-1 microg/L) Pb in base water to 177+/-7 (37+/-1 microg/L) and 187+/-7 nM (39+/-1 microg/L) Pb in CaSO(4)- or HA-supplemented water, respectively. Fish were collected at 2, 4, 10, 30, 63, 90 and 150 days of exposure. Traditional toxicological endpoints were examined alongside gene transcription analyses to help clarify the underlying mechanisms of Pb toxicity and to identify candidate molecular markers that might ultimately serve as robust indicators of exposure and effect. Addition of CaSO(4) did not prevent whole body Pb accumulation whereas DOC afforded strong protection (about half the amount accumulated by fish in base water) suggesting that current, hardness-based WQC are likely inaccurate for predicting chronic Pb effects in aquatic systems. Custom-made microarrays were co-hybridized with base water samples+/-Pb up to the 30 days time point. Quantitative PCR was employed to verify gene transcription responses and to extend analysis to the CaSO(4) and HA treatments and the 150 days time point. Identification of four genes by microarray analysis revealed clear Pb-induced responses over time: glucose-6-phosphate dehydrogenase, glutathione-S-transferase, ferritin and beta-globin. Results obtained by qPCR were in strong agreement with microarray data by regression analysis (r(2)=0.82, slope=1.28). The associated pathways implicated herein for these genes provide further evidence supporting roles for anemia and neurological disorders in

  14. Larval exposure to environmentally relevant mixtures of alkylphenolethoxylates reduces reproductive competence in male fathead minnows

    USGS Publications Warehouse

    Bistodeau, T.J.; Barber, L.B.; Bartell, S.E.; Cediel, R.A.; Grove, K.J.; Klaustermeier, J.; Woodard, J.C.; Lee, K.E.; Schoenfuss, H.L.

    2006-01-01

    The ubiquitous presence of nonylphenolethoxylate/octylphenolethoxylate (NPE/OPE) compounds in aquatic environments adjacent to wastewater treatment plants (WWTP) warrants an assessment of the endocrine disrupting potential of these complex mixtures on aquatic vertebrates. In this study, fathead minnow larvae were exposed for 64 days to a mixture of NPE/OPE, which closely models the NPE/OPE composition of a major metropolitan WWTP effluent. Target exposure concentrations included a total NPE/OPE mixture load of 200% of the WWTP effluent concentration (148 ??g/L), 100% of the WWTP effluent concentration (74 ??g/L) and 50% of the WWTP effluent concentration (38 ??g/L). The NPE/OPE mixture contained 0.2% 4-t-octylphenol, 2.8% 4-nonylphenol, 5.1% 4-nonylphenolmonoethoxylate, 9.3% 4-nonylphenoldiethoxylate, 0.9% 4-t-octylphenolmonoethoxylate, 3.1% 4-t-octylphenoldiethoxylate, 33.8% 4-nonylphenolmonoethoxycarboxylate, and 44.8% 4-nonylphenoldiethoxycarboxylate. An additional exposure of 5 ??g/L 4-nonylphenol (nominal) was conducted. The exposure utilized a flow-through system supplied by ground water and designed to deliver consistent concentrations of applied chemicals. Following exposure, larvae were raised to maturity. Upon sexual maturation, exposed male fish were allowed to compete with control males in a competitive spawning assay. Nest holding ability of control and exposed fish was carefully monitored for 7 days. All male fish were then sacrificed and analyzed for plasma vitellogenin, developmental changes in gonadal tissues, alterations in the development of secondary sexual characters, morphometric changes, and changes to reproductive behavior. When exposed to the 200% NPE/OPE treatment most larvae died within the first 4 weeks of exposure. Both the 100% and 50% NPE/OPE exposures caused a significant decrease in reproductive behavior, as indicated by an inability of many of the previously exposed males to acquire and hold a nest site required for reproduction

  15. Effects of a short-term exposure to the fungicide prochloraz on endocrine function and gene expression in female fathead minnows (Pimephales promelas).

    PubMed

    Skolness, Sarah Y; Durhan, Elizabeth J; Garcia-Reyero, Natalia; Jensen, Kathleen M; Kahl, Michael D; Makynen, Elizabeth A; Martinovic-Weigelt, Dalma; Perkins, Edward; Villeneuve, Daniel L; Ankley, Gerald T

    2011-06-01

    Prochloraz is a fungicide known to cause endocrine disruption through effects on the hypothalamic-pituitary-gonadal (HPG) axis. To determine the short-term impacts of prochloraz on gene expression and steroid production, adult female fathead minnows (Pimephales promelas) were exposed to the chemical (0 or 300 μg/L) for a time-course of 6, 12 and 24 h. Consistent with inhibition of cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17) and aromatase (CYP19), known molecular targets of prochloraz, plasma 17β-estradiol (E2) was reduced within 6 h. Ex vivo E2 production was significantly reduced at all time-points, while ex vivo testosterone (T) production remained unchanged. Consistent with the decrease in E2 levels, plasma concentrations of the estrogen-responsive protein vitellogenin were significantly reduced at 24 h. Genes coding for CYP19, CYP17, and steroidogenic acute regulatory protein were up-regulated in a compensatory manner in ovaries of the prochloraz-treated fish. In addition to targeted quantitative real-time polymerase chain reaction analyses, a 15k feature fathead minnow microarray was used to determine gene expression profiles in ovaries. From time-point to time-point, the microarray results showed a relatively rapid change in the differentially expressed gene (DEG) profiles associated with the chemical exposure. Functional analysis of the DEGs indicated changes in expression of genes associated with cofactor and coenzyme binding (GO:0048037 and 0050662), fatty acid binding (GO:0005504) and organelle organization and biogenesis (GO:0006996). Overall, the results from this study are consistent with compensation of the fish HPG axis to inhibition of steroidogenesis by prochloraz, and provide further insights into relatively rapid, system-wide, effects of a model chemical stressor on fish.

  16. From single chemicals to mixtures--reproductive effects of levonorgestrel and ethinylestradiol on the fathead minnow.

    PubMed

    Runnalls, Tamsin J; Beresford, Nicola; Kugathas, Subramaniam; Margiotta-Casaluci, Luigi; Scholze, Martin; Scott, Alexander P; Sumpter, John P

    2015-12-01

    The aquatic environment is polluted with thousands of chemicals. It is currently unclear which of these pose a significant threat to aquatic biota. The typical exposure scenario is now represented by a widespread blanket of contamination composed of myriads of individual pollutants-each typically present at a low concentration. The synthetic steroids, 17α-ethinylestradiol and levonorgestrel, have been widely reported to be present in the aquatic environment in the low ng to sub-ng/l range. They are widely used in contraceptive formulations, both individually and in combination. Our research employed the fathead minnow (Pimephales promelas) 21 day 'pair-breeding' assay to assess reproductive output when pairs of fish were exposed to the single chemicals at low environmentally relevant concentrations, and then to a binary mixture of them. A variety of endpoints were assessed, including egg production, which was inhibited in a concentration-dependent manner by both the individual chemicals and the mixture. Significant, sex specific effects were also seen with both chemicals, at differing levels of biological organisation. Plasma concentrations of EE2 and levonorgestrel were predicted and in the case of levonorgestrel measured, and compared with the human therapeutic plasma concentrations (Read-Across approach) to support the interpretation of the results. A novel quantitative method was developed for the data analysis, which ensured a suitable endpoint for the comparative mixture assessment. This approach compares the reproductive performance from individual pairs of fish during chemical exposure to its pre-treatment performance. The responses from the empirical mixture study were compared to predictions derived from the single substance data. We hypothesised combined responses which were best described by the concept of concentration addition, and found no clear indications against this additivity expectation. However, the effect profiles support the current

  17. Fathead minnow nidovirus infects spotfin shiner Cyprinella spiloptera and golden shiner Notemigonus crysoleucas.

    PubMed

    Baird, Ashley; Faisal, Mohamed

    2016-04-12

    Since the initial isolation of the fathead minnow nidovirus (FHMNV), concerns have been raised regarding the risks it may pose to other fish species. In this study, 7 fish species resident to the Laurentian Great Lakes were challenged intraperitoneally with 2 doses of FHMNV: 102.8 and 104.8 median tissue culture infective dose (TCID(50)) ml(-1). Infected spotfin shiner Cyprinella spiloptera and golden shiner Notemigonus crysoleucas suffered morbidity and mortality during the 40 d observation period, while other species, including creek chub Semotilus atromaculatus, rainbow trout Oncorhynchus mykiss, largemouth bass Micropterus salmoides and walleye Sander vitreus, showed no clinical signs or mortality. FHMNV was re-isolated on the epithelioma papulosum cyprini cell line from the tissues of infected spotfin shiner and golden shiner, which harbored high numbers of viral RNA copies as measured by quantitative loop-mediated isothermal amplification. Infected spotfin shiner and golden shiner exhibited external petechiae, exophthalmia, oedematous kidneys, and liver pallor. Histopathological analysis revealed multifocal areas of necrosis in the kidney, spleen and liver of infected fish. Spotfin shiner and golden shiner were then infected with 2 doses of FHMNV (10(3.5) and 10(3.9) TCID(50) ml(-1)) by immersion to mimic more natural modes of infection. Spotfin shiner experienced 60% mortality at both doses, while golden shiner did not experience mortality nor develop any clinical signs following a 40 d observation period. Overall, piscivorous fish tested in this study do not seem to be at risk for infection, while cyprinids appear to vary in their susceptibility to the strain of FHMNV used in this study. PMID:27068501

  18. Transcriptional networks associated with 5-alpha-dihydrotestosterone in the fathead minnow (Pimephales promelas) ovary.

    PubMed

    Ornostay, Anna; Marr, Joshua; Loughery, Jennifer R; Martyniuk, Christopher J

    2016-01-01

    Androgens play a significant role in regulating oogenesis in teleost fishes. The androgen dihydrotestosterone (DHT) is a potent non-aromatizable androgen involved in sexual differentiation in mammals; however, its actions are not well understood in teleost fish. To better characterize the physiological role of DHT in the fathead minnow (FHM) ovary on a temporal scale, in vitro assays for 17β-estradiol (E2) production were conducted in parallel with microarray analysis. Ovarian explants were incubated at different concentrations of DHT (10(-6), 10(-7), and 10(-8)M DHT) in three separate experiments conducted at 6, 9, and 12h. DHT treatment resulted in a rapid and consistent increase in E2 production from the ovary at all three time points. Therefore, DHT may act to shift the balance of metabolites in the steroidogenic pathway within the ovary. Major biological themes affected by DHT in the ovary in one or more of the time points included those related to blood (e.g. vasodilation, blood vessel contraction, clotting), lipids (e.g. lipid storage, cholesterol metabolism, lipid degradation) and reproduction (e.g. hormone and steroid metabolism). Gene networks related to immune responses and calcium signaling were also affected by DHT, suggesting that this androgen may play a role in regulating these processes in the ovary. This study detected no change in mRNA levels of steroidogenic enzymes (cyp19a1, star, 11βhsd, 17βhsd, srd5a isoforms), suggesting that the observed increase in E2 production is likely more dependent on the pre-existing gene or protein complement in the ovary rather than the de novo expression of transcripts. This study increases knowledge regarding the roles of DHT and androgens in general in the teleost ovary and identifies molecular signaling pathways that may be associated with increased E2 production.

  19. Endocrine-disrupting effects of cattle feedlot effluent on an aquatic sentinel species, the fathead minnow.

    PubMed

    Orlando, Edward F; Kolok, Alan S; Binzcik, Gerry A; Gates, Jennifer L; Horton, Megan K; Lambright, Christy S; Gray, L Earl; Soto, Ana M; Guillette, Louis J

    2004-03-01

    Over the last decade, research has examined the endocrine-disrupting action of various environmental pollutants, including hormones, pharmaceuticals, and surfactants, in sewage treatment plant effluent. Responding to the growth of concentrated animal feeding operations (CAFOs) and the pollutants present in their wastewater (e.g., nutrients, pharmaceuticals, and hormones), the U.S. Environmental Protection Agency developed a new rule that tightens the regulation of CAFOs. In this study, we collected wild fathead minnows (Pimephales promelas) exposed to feedlot effluent (FLE) and observed significant alterations in their reproductive biology. Male fish were demasculinized (having lower testicular testosterone synthesis, altered head morphometrics, and smaller testis size). Defeminization of females, as evidenced by a decreased estrogen:androgen ratio of in vitro steroid hormone synthesis, was also documented. We did not observe characteristics in either male or female fish indicative of exposure to environmental estrogens. Using cells transfected with the human androgen receptor, we detected potent androgenic responses from the FLE. Taken together, our morphologic, endocrinologic, and in vitro gene activation assay data suggest two hypotheses: a) there are potent androgenic substance(s) in the FLE, and/or b) there is a complex mixture of androgenic and estrogenic substances that alter the hypothalamic-pituitary-gonadal axis, inhibiting the release of gonadotropin-releasing hormone or gonadotropins. This is the first study demonstrating that the endocrine and reproductive systems of wild fish can be adversely affected by FLE. Future studies are needed to further investigate the effects of agricultural runoff and to identify the biologically active agents, whether natural or pharmaceutical in origin.

  20. Direct Effects, Compensation, and Recovery in Female Fathead Minnows Exposed to a Model Aromatase Inhibitor

    PubMed Central

    Villeneuve, Daniel L.; Mueller, Nathaniel D.; Martinović, Dalma; Makynen, Elizabeth A.; Kahl, Michael D.; Jensen, Kathleen M.; Durhan, Elizabeth J.; Cavallin, Jenna E.; Bencic, David; Ankley, Gerald T.

    2009-01-01

    Background Several chemicals in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. Objectives The objective of this study was to provide a detailed characterization of molecular and biochemical responses of female fathead minnows to a model aromatase inhibitor, fadrozole (FAD). Methods Fish were exposed via water to 0, 3, or 30 μg FAD/L for 8 days and then held in clean water for 8 days, with samples collected at four time points during each 8-day period. We quantified ex vivo steroid production, plasma steroids, and plasma vitellogenin (Vtg) concentrations and analyzed relative transcript abundance of 10 key regulatory genes in ovaries and 3 in pituitary tissue by real-time polymerase chain reaction. Results Ex vivo 17β-estradiol (E2) production and plasma E2 and Vtg concentrations were significantly reduced after a single day of exposure to 3 μg or 30 μg FAD/L. However, plasma E2 concentrations recovered by the eighth day of exposure in the 3-μg/L group and within 1 day of cessation of exposure in the 30-μg/L group, indicating concentration- and time-dependent physiologic compensation and recovery. Concentration-dependent increases in transcripts coding for aromatase (A isoform), cytochrome P450 side-chain cleavage, steroidogenic acute regulatory protein, and follicle-stimulating hormone receptor all coincided with increased E2 production and recovery of plasma E2 concentrations. Conclusions Results of this research highlight the need to consider compensation/adaptation and recovery when developing and interpreting short-term bioassays or biomarkers or when trying to predict the effects of chemical exposures based on mode of action. PMID:19440503

  1. Effects of Ammonium Perchlorate on Thyroid Function in Developing Fathead Minnows, Pimephales promelas

    PubMed Central

    Crane, Helen M.; Pickford, Daniel B.; Hutchinson, Thomas H.; Brown, J. Anne

    2005-01-01

    Perchlorate is a known environmental contaminant, largely due to widespread military use as a propellant. Perchlorate acts pharmacologically as a competitive inhibitor of thyroidal iodide uptake in mammals, but the impacts of perchlorate contamination in aquatic ecosystems and, in particular, the effects on fish are unclear. Our studies aimed to investigate the effects of concentrations of ammonium perchlorate that can occur in the environment (1, 10, and 100 mg/L) on the development of fathead minnows, Pimephales promelas. For these studies, exposures started with embryos of < 24-hr postfertilization and were terminated after 28 days. Serial sectioning of thyroid follicles showed thyroid hyperplasia with increased follicular epithelial cell height and reduced colloid in all groups of fish that had been exposed to perchlorate for 28 days, compared with control fish. Whole-body thyroxine (T4) content (a measure of total circulating T4) in fish exposed to 100 mg/L perchlorate was elevated compared with the T4 content of control fish, but 3,5,3′-triiodothyronine (T3) content was not significantly affected in any exposure group. Despite the apparent regulation of T3, after 28 days of exposure to ammonium perchlorate, fish exposed to the two higher levels (10 and 100 mg/L) were developmentally retarded, with a lack of scales and poor pigmentation, and significantly lower wet weight and standard length than were control fish. Our study indicates that environmental levels of ammonium perchlorate affect thyroid function in fish and that in the early life stages these effects may be associated with developmental retardation. PMID:15811828

  2. Oocyte atresia and reproductive success in fathead minnows (Pimephales promelas) exposed to acidified hardwater environments.

    PubMed

    McCormick, J H; Stokes, G N; Hermanutz, R O

    1989-01-01

    The ovarian histology of fathead minnows (Pimephales promelas) chronically exposed to three levels of environmental pH was examined for evidence of reproductive impairment. Exposures occurred in three experimental running-water channels receiving Mississippi River water. One of these channels was not acidified and two were dosed with H2SO4. The pH was approximately 8 in untreated river water and 6 and 5 in the two channels receiving H2SO4. Fish for ovarian examination were taken from these channels at four stages of the reproductive season: initiation of spawning (June 19), mid-spawning (July 12), end of spawning (August 14-15), and approximately 1 mo. post-spawning (September 19). The fish exhibited ovarian histological changes and depression of reproductive success which were directly associated with the level of environmental stress experienced. The association between these three factors was most consistent and pronounced if the fish were sampled near the end of the spawning season. When sampled at this time, reproductive impairment in a population was found when the ratio of the volume of atretic (resorbing) oocytes present in the ovary to the total ovarian volume exceeded 20% in all fish sampled. This was the case in the pH 5 channel fish sampled in August. At this same time, not all of the fish in the pH 6 channel exhibited such an accumulation of atretic oocytes, and egg deposition in that population was not reduced. None of the fish from the pH 8 channel were so affected nor was their reproduction.

  3. Enzyme genotype and exposure tolerance in fathead minnow populations acutely and chronically exposed to fluoranthene

    SciTech Connect

    Diamond, S.; Oris, J.T.; Guttman, S.I.

    1995-12-31

    Populations residing in contaminated areas often exhibit enhanced genetically based tolerance. Shifts in enzyme genotype frequencies have been suggested as indicators of these adaptive responses. However, the between extant tolerance and enzyme genotype frequencies in affected populations has not been previously reported. The authors report here on attempts, involving acute and chronic exposures, to select for tolerance in populations of fathead minnows. Offspring of survivors of an acutely exposed population were significantly less tolerant relative to naive fish, whereas offspring of fish exposed to a sub-lethal concentration were significantly more tolerant of exposure. Relationships between differential response in the acute exposure were elucidated using failure-time methods. Genotype at one focus, glucose phosphate isomerase (GPI), was significantly related to survival time during this exposure. In addition, significant differences in GPI allele frequency between survivors and their offspring were also apparent. Comparison of offspring of chronically exposed fish with offspring of unexposed fish indicated a significant shift in allele frequencies at the GPI locus. These F1 populations were also exposed acutely to fluoranthene to assess their relative tolerance. Separate failure-time analyses for these populations again indicated a significant relationship between GPI genotype and mortality in the control fish (and at three other loci), but not in the exposure fish. Overall, five loci were significantly related to mortality in the control population, whereas one locus was related to mortality in the exposure offspring. These results suggest that enzyme genotype frequencies can be consistent indicators of population response to exposure and that selection by contaminants may reduce variability in these relationships.

  4. Linking biomarkers to reproductive success of caged fathead minnows in streams with increasing urbanization

    USGS Publications Warehouse

    Crago, J.; Corsi, S.R.; Weber, D.; Bannerman, R.; Klaper, R.

    2011-01-01

    Reproductive and oxidative stress biomarkers have been recommended as tools to assess the health of aquatic organisms. Though validated in the laboratory, there are few studies that tie a change in gene expression to adverse reproductive or population outcomes in the field. This paper looked at 17 streams with varying degrees of urbanization to assess the use of biomarkers associated with reproduction or stress in predicting reproductive success of fathead minnows. In addition, the relationship between biomarkers and water quality measures in streams with varying degrees of urbanization was examined. Liver vitellogenin mRNA was correlated with reproduction within a period of 11. d prior to sampling irrespective of habitat, but its correlation with egg output declined at 12. d and beyond indicating its usefulness as a short-term biomarker but its limits as a biomarker of total reproductive output. Stress biomarkers such as glutathione S-transferase may be better correlated with factors affecting reproduction over a longer term. There was a significant correlation between GST mRNA and a variety of anthropogenic pollutants. There was also an inverse correlation between glutathione S-transferase and the amount of the watershed designated as wetland. Egg production over the 21-d was negatively correlated with the amount of urbanization and positively correlated to wetland habitats. This study supports the development of multiple biomarkers linking oxidative stress and other non-reproductive endpoints to changes in aquatic habitats will be useful for predicting the health of fish populations and identifying the environmental factors that may need mitigation for sustainable population management. ?? 2010 Elsevier Ltd.

  5. Propiconazole inhibits steroidogenesis and reproduction in the fathead minnow (Pimephales promelas).

    PubMed

    Skolness, Sarah Y; Blanksma, Chad A; Cavallin, Jenna E; Churchill, Jessica J; Durhan, Elizabeth J; Jensen, Kathleen M; Johnson, Rodney D; Kahl, Michael D; Makynen, Elizabeth A; Villeneuve, Daniel L; Ankley, Gerald T

    2013-04-01

    Conazoles are designed to inhibit cytochrome P450 (CYP) 14α-demethylase, an enzyme key to fungal cell wall formation. In vertebrates, conazoles may inhibit other CYPs, potentially disrupting processes like sex steroid synthesis. Propiconazole is a current-use pesticide that is among the first chemicals being tested in the U.S. Environmental Protection Agency endocrine disruptor screening program. Fathead minnows (Pimephales promelas) were exposed to 0, 5, 50, 500, or 1000 µg propiconazole/l in a 21-day study that evaluated apical reproductive endpoints (fecundity, fertility, hatch); measures of endocrine function and steroid synthesis, such as cholesterol, vitellogenin (VTG), and sex steroid (testosterone [T], 17β-estradiol [E2]) concentrations in the plasma; and changes in gonadal expression of steroidogenic genes. Plasma E2 and VTG concentrations in females were reduced by exposure to propiconazole, and egg production was decreased in the 500 and 1000 µg/l treatment groups. These in vivo effects coincided with inhibition of E2 synthesis by ovary explants exposed to propiconazole in vitro. We also observed a compensatory response in females exposed to propiconazole, manifested as increased gonad weight and upregulation of genes coding for key steriodogenic proteins, including CYP19 (aromatase), CYP17 (hydroxylase/lyase), CYP11A (cholesterol side-chain-cleavage), and steroidogenic acute regulatory protein. Other than an increase in relative testis weight, effects on endocrine function in males were less pronounced than in females. This study provides important data relative to the potential endocrine activity of propiconazole in fish and, more generally, to the further delineation of pathways for the reproductive effects of steroid synthesis inhibitors in fish.

  6. Computational Modeling of Hypothalamic-Pituitary-Gonadal Axis to Predict Adaptive Responses in Female Fathead Minnows Exposed to an Aromatase Inhibitor

    EPA Science Inventory

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose response and time-course...

  7. Pathogenesis of spring viremia of carp virus in emerald shiner Notropis atherinoides Rafinesque, fathead minnow Pimephales promelas Rafinesque and white sucker Catostomus commersonii (Lacepede).

    PubMed

    Misk, E; Garver, K; Nagy, E; Isaac, S; Tubbs, L; Huber, P; Al-Hussinee, L; Lumsden, J S

    2016-06-01

    Spring viremia of carp (SVC) is a reportable disease to the World Organization of Animal Health (OIE) as it is known to cause significant international economic impact. In Canada, the first and only isolation of SVC virus (SVCV) was in 2006, from common carp Cyprinus carpio L., at Hamilton Harbour, Lake Ontario. The susceptibility of fathead minnow Pimephales promelas Rafinesque, emerald shiner Notropis atherinoides Rafinesque and white sucker Catostomus commersonii (Lacepede) to intraperitoneal injection of the Canadian isolate (HHOcarp06) was evaluated using experimental infection, virus isolation, quantitative reverse transcription polymerase chain reaction (qRT-PCR), histopathology and immunohistochemistry (IHC). Emerald shiner and fathead minnow were most susceptible with 43 and 53% cumulative mortality, respectively, compared with koi at 33%. Quantitative RT-PCR demonstrated that koi had high viral loads throughout the experiment. At 34 days post-infection, SVCV was detected from sampled emerald shiner and white sucker in very low titre and was not detected from fathead minnow. Koi, fathead minnow and emerald shiner had gross lesions typical of SVC disease. The histopathological picture was mostly dominated by necrotic changes in kidney, spleen, liver, pancreas and intestine. IHC further confirmed SVCV infection, and staining was largely correlated with histological lesions. PMID:26411333

  8. A Method for the Determination of Genetic Sex in the Fathead Minnow, Pimephales promelas, to Support Testing of Endocrine-active Chemicals

    EPA Science Inventory

    Fathead minnows are used as a model fish species for the characterization of the endocrine-disrupting potential of environmental contaminants. This research describes the development of a PCR method that can determine the genetic sex in this species. This method, when incorpora...

  9. CDNA CLONING OF FATHEAD MINNOW (PIMEPHALES PROMELAS) ESTROGEN AND ANDROGEN RECEPTORS FOR USE IN STEROID RECEPTOR EXTRAPOLATION STUDIES FOR ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    cDNA Cloning of Fathead minnow (Pimephales promelas) Estrogen and Androgen Receptors for Use in Steroid Receptor Extrapolation Studies for Endocrine Disrupting Chemicals.

    Wilson, V.S.1,, Korte, J.2, Hartig P. 1, Ankley, G.T.2, Gray, L.E., Jr 1, , and Welch, J.E.1. 1U.S...

  10. EVALUATION OF THE MODEL ANTI-ANDROGEN FLUTAMIDE FOR ASSESSING THE MECHANISTIC BASIS OF RESPONSES TO AN ANDROGEN IN THE FATHEAD MINNOW

    EPA Science Inventory

    In this study we characterized the effects of flutamide, a model mammalian androgen receptor (AR) antagonist, on endocrine function in the fathead minnow (Pimephales promelas), a small fish species which is widely used for testing endocrine-disrupting chemicals (EDCs). Binding as...

  11. EVALUATION OF THE ROBUSTNESS OF THE FATHEAD MINNOW, PIMEPHALES PROMELAS, LARVAL SURVIVAL AND GROWTH TEST, U.S. EPA METHOD 1000.0

    EPA Science Inventory

    An intralaboratory study was conducted to evaluate the robustness of the Fathead Minnow (Pimephales promelas) Larval Survival and Growth Test, Method 1000.0 Toxicity tests were conducted with the reference toxicants hexavalent chromium (Cr6+) and copper (Cu), and the data were st...

  12. Comparison of Chemical Binding to Recombinant Fathead minnow and Human Estrogen Receptor alpha (ERα) in Whole Cell and Cell-Free Assay Systems.

    EPA Science Inventory

    Our objectives were to assess whether binding of chemicals differs significantly between recombinant estrogen receptors from fathead minnow (fhERα) and human (hERα) and to evaluate the performance of these receptors using two different in vitro assay systems: a COS whole cell bin...

  13. EVALUATION OF THE MODEL ANTI-ANDROGEN FLUTAMIDE FOR ASSESSING THE MECHANISTIC BASIS OF RESPONSES TO AN ANDROGEN IN THE FATHEAD MINNOW (JOURNAL ARTICLE)

    EPA Science Inventory

    In this study we characterized the effects of flutamide, a model mammalian androgen receptor (AR) antagonist, on endocrine function in the fathead minnow (Pimephales promelas), a small fish species which is widely used for testing endocrine-disrupting chemicals (EDCs). Binding a...

  14. Progress Towards the Development of a Fathead Minnow Embryo Test and Comparison to the Zebrafish Embryo Test for Assessing Acute Fish Toxicity

    EPA Science Inventory

    The Zebrafish Embryo Test (ZFET) for acute fish toxicity is a well developed method nearing adoption as an OECD Test Guideline. Early drafts of the test guideline (TG) envisioned a suite of potential test species to be covered including zebrafish, fathead minnow, Japanese Medaka...

  15. Effects of short time-course exposure to antiandrogen flutamide on steroidogenesis and gene expression in ovary of female fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Because the mechanisms through which antiandrogens disrupt reproduction in fish are not well-characterized, this work sought to identify genes and pathways affected by antiandrogen exposure, and to compare differentially expressed genes in the fathead minnow to those previously r...

  16. Inference of chemicals that cause biological effects in treated pulp and paper mill effluent using gene expression in caged fathead minnows

    EPA Science Inventory

    Analytical chemistry techniques can identify chemicals present in the waters of the Great Lakes areas of concern, however it remains a challenge to identify those chemicals or classes of chemicals that actually cause adverse effects. Use of caged fathead minnows (Pimephales prome...

  17. Field-Based Approach for Assessing the Impact of Treated Pulp and Paper Mill Effluent on Endogenous Metabolites of Fathead Minnows (Pimephales promelas)

    EPA Science Inventory

    A field-based metabolomic study was conducted during a shutdown of a pulp and paper mill (PPM) to assess the impacts of treated PPM effluent on endogenous polar metabolites in fathead minnow (FHM; Pimephales promelas) livers. Caged male and female FHMs were deployed at a Great La...

  18. MODELLING IMPACTS ON POPULATIONS: FATHEAD MINNOW (PIMEPHALES PROMELAS) EXPOSURE TO THE ENDOCRINE DISRUPTOR 17-B-TRENBOLONE AS A CASE STUDY

    EPA Science Inventory

    Evaluation of population-level impacts is critical to credible ecological risk assessments. In this study, a predictive model was developed to translate changes in fecundity of the fathead minnow in a short term laboratory toxicity test to alterations in population growth rate. T...

  19. The effectiveness of flow-through and/or static copper sulfate treatments on the survival of Golden Shiners and Fathead Minnows infected with Flavobacterium columare

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four studies were done comparing various treatments of copper sulfate (CuSO4) on the survival of golden shiner and fathead minnow (both economically important baitfish) that had columnaris disease. The treatments were observed for their ability to reduce mortality in well water. In experiment 1 and ...

  20. The effectiveness of flow-through and/or static copper sulfate treatments on the survival of Golden Shiners and Fathead Minnows infected with Flavobacterium columare

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four studies were done comparing various treatments of copper sulfate (CuSO4) on the survival of golden shiner and fathead minnow (both economically important baitfish) that had columnaris disease. The treatments were observed for their ability to reduce mortality in well water. In experiment 1 an...

  1. Effects-based monitoring in the lower Green Bay/Fox River and Milwaukee Estuary Areas of Concern using caged Fathead Minnows (Pimephales promelas)

    EPA Science Inventory

    Within the Great Lakes there is an increased focus on contaminants of emerging concern (CECs) and their potential effects on aquatic organisms, including adverse reproductive effects. To further characterize the utility of caged fathead minnows (Pimephales promelas) for effects-b...

  2. Profiling Lipid Metabolites Yields Unique Information on Sex- and Time-dependent Responses of Fathead Minnows (Pimephales promelas) Exposed to 17α-Ethynylestradiol

    EPA Science Inventory

    Alterations in hepatic lipid profiles of fathead minnows (FHM) exposed to the synthetic estrogen 17α-ethynylestradiol (EE2) were determined using 1H-NMR spectroscopy-based metabolite profiling. The exposures were conducted using either 10 ng/l or 100 ng/l EE2 via a continuous flo...

  3. Effects-based Monitoring with Caged Fathead Minnows: An Exposure Gradient Case Study in the Duluth-Superior Harbor, USA (SETAC meeting)

    EPA Science Inventory

    Within the Great Lakes there is an increased focus on contaminants of emerging concern (CECs) and consideration of potential effects of chemical mixtures. To further characterize the utility of caged fathead minnows (Pimephales promelas) for effects-based monitoring of CECs, we c...

  4. Impacts of an Anti-androgen and an Androgen/anti-androgen Mixture on the Metabolite Profile of Male Fathead Minnow Urine

    EPA Science Inventory

    Male and female fathead minnows (FHM) were exposed via the water to cyproterone acetate (CA), a model androgen receptor (AR) antagonist. FHM were also exposed to 517b-trenbolone (TB), a model AR agonist, and to mixtures of TB with CA. The urine metabolite profile of male FHM ex...

  5. Impacts of an Anti-Androgen and an Adrogen/Anti-Androgen Mixture on the Metabolite Profile of Male Fathead Minnow Urine

    EPA Science Inventory

    Male and female fathead minnows (Pimephales promelas, FHM) were exposed via water to 20 or 200 μg/L of cyproterone acetate (CA), a model androgen receptor (AR) antagonist. FHM were also exposed to 500 ng/L of 17β-trenbolone (TB), a model AR agonist, and to mixtures of TB with bot...

  6. Early Life Stage Exposure to BDE-47 Causes Adverse Effects on Reproductive Success and Sexual Differentiation in Fathead Minnows (Pimephales promelas).

    PubMed

    Thornton, Leah M; Path, Elise M; Nystrom, Gunnar S; Venables, Barney J; Sellin Jeffries, Marlo K

    2016-07-19

    2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a compound manufactured for use as a flame retardant, is a ubiquitous environmental contaminant and suspected endocrine disruptor. Though several studies have explored the reproductive effects of BDE-47 in adult fish, there is a paucity of data regarding the reproductive effects of early life stage exposure. The goal of this study was to assess the reproductive effects of early life stage BDE-47 exposure in fathead minnows (Pimephales promelas). To achieve this, minnows were exposed to either a low (57.68 μg BDE-47/g Artemia) or high (392.59 μg BDE-47/g Artemia) dose of BDE-47 from fertilization to 34 days postfertilization (dpf) via a combination of maternal transfer and dietary exposure. Larvae were then raised on a clean diet until sexual maturity (∼184 dpf) when reproductive function was evaluated using a 21 day breeding study. Fish exposed to BDE-47 had significantly reduced clutch size and fecundity relative to controls. BDE-47 exposed groups also had female-biased sex ratios and exposed males had fewer tubercles. Overall, this study demonstrates that exposure to BDE-47 during early life stages can alter both sexual differentiation and reproductive function. PMID:27326452

  7. Modeling impacts on populations: fathead minnow (Pimephales promelas) exposure to the endocrine disruptor 17beta-trenbolone as a case study.

    PubMed

    Miller, David H; Ankley, Gerald T

    2004-09-01

    Evaluation of population-level impacts is critical to credible ecological risk assessments. In this study, a predictive model was developed to translate changes in fecundity of the fathead minnow (Pimephales promelas) in a short-term laboratory toxicity test to alterations in population growth rate. The model uniquely combines a Leslie population projection matrix and the logistic equation. Application of the model requires only a life table for the organism of interest, a measure of carrying capacity for the given population, and an estimation of the effect of a stressor on vital rates. The model was applied to investigate population dynamics for fathead minnow exposed to the androgen receptor agonist 17beta-trenbolone. Organismal-level responses for fathead minnows exposed to varying levels of 17beta-trenbolone were used to determine projected alterations in a population existing in a small body of water containing varying concentrations of the androgen. Fathead minnow populations occurring at carrying capacity and subsequently exposed to 0.027 microg/L of 17beta-trenbolone exhibited a 51% projected decrease in average population size after 2 years of exposure. Populations at carrying capacity exposed to concentrations of 17beta-trenbolone > or = 0.266 microg/L exhibited a 93% projected decrease in average population size after 2 years of exposure. Overall, fathead minnow populations exposed to continued concentrations of 17beta-trenbolone equal to or greater than 0.027 microg/L were projected to have average equilibrium population sizes that approached zero.

  8. Effects of acute exposure to fluoranthene-contaminated sediment on the survival and genetic variability of fathead minnows (Pimephales promelas)

    SciTech Connect

    Schlueter, M.A.; Guttman, S.I.; Duan, Y.; Oris, J.T.; Huang, X.; Burton, G.A.

    2000-04-01

    One-month-old fathead minnows (Pimephales promelas) were exposed to fluoranthene-contaminated sediment during a 96-h exposure. Of the 909 minnows exposed to fluoranthene, 684 (75%) minnows died during the exposure. Horizontal starch-gel electrophoresis was used to determine genotypes at six variable enzyme loci ({beta}-GAL*, GPI-1*, GPI-2*, IDHP-1*, MDH-2*, and PGM*). Statistical analyses were used to evaluate the relationships between the genetic data and weight, length, and time to death (TTD) of fish using an accelerated failure time regression model (LIFEREG). The GPI-1*, MDH-2*, and PGM* loci were found to be significantly related to TTD. Multilocus heterozygosity was also related to TTD. Lower heterozygosity was related to a longer TTD and a greater chance of survival. Mean fish weight differed significantly among genotypes at each locus. This resulted in large differences between LIFEREG regression models that factored weight out and those models that die not separate weight from the genotypes or multilocus heterozygosity. The results of the study indicated that differential survival to fluoranthene was genetically related. The frequencies of several genotypes were significantly different in the survivors of the fluoranthene exposure compared with those in the initial population.

  9. Influence of water quality and age on nickel toxicity to fathead minnows (Pimephales promelas).

    PubMed

    Hoang, Tham Chung; Tomasso, Joseph R; Klaine, Stephen J

    2004-01-01

    This research characterized the effects of water quality and organism age on the toxicity of nickel (Ni) to fathead minnows (Pimephales promelas) to facilitate the accurate development of site-specific water-quality criteria. Nickel sulfate hexahydrate (NiSO4 x 6H2O) was used as the Ni source for performing acute toxicity tests (median lethal concentration after 96-h exposure [96-h LC50]) with < 1-d-old and 28-d-old P. promelas under varying regimes of hardness, pH, alkalinity, and natural organic matter (NOM). The toxicity of Ni was inversely related to water hardness between hardness values of 20 and 150 mg/L (as CaCO3). Below 30 mg/L alkalinity, Ni toxicity was related to alkalinity. The effect of pH was confounded by hardness and the presence of NOM. In the absence of NOM, the toxicity of Ni increased as pH increased at high hardness and alkalinity. In general, 28-d-old fish were less sensitive than < 1-d-old fish to Ni. This lower sensitivity ranged from 12-fold at low hardness and alkalinity (20 and 4 mg/L, respectively) to 5-fold at high hardness and alkalinity (100 and 400 mg/L, respectively). The presence of NOM (10 mg/L as dissolved organic carbon [DOC]) reduced Ni toxicity by up to 50%, but this effect appeared to be saturated above DOC at 5 mg/L. Incubating Ni with the NOM solution from 1 to 17 days had no effect on Ni toxicity. When using multivariate analysis, the 96-h LC50 for Ni was a function of fish age, alkalinity, hardness, and NOM (96-h LC50 = -0.642 + 0.270(fish age) + 0.005(alkalinity) + 0.018(hardness) + 0.138(DOC)). When using this model, we found a strong relationship between measured and predicted 96-h LC50 values (r2 = 0.94) throughout the treatment water qualities. The biotic ligand model (BLM) did not accurately predict Ni toxicity at high or low levels of alkalinity. Results of our research suggest that the BLM could be improved by considering NiCO3 to be bioavailable.

  10. Levonorgestrel exposure to fathead minnows (Pimephales promelas) alters survival, growth, steroidogenic gene expression and hormone production.

    PubMed

    Overturf, Matthew D; Overturf, Carmen L; Carty, Dennis R; Hala, David; Huggett, Duane B

    2014-03-01

    Human pharmaceuticals are commonly detected in the environment. Concern over these compounds in the environment center around the potential for pharmaceuticals to interfere with the endocrine system of aquatic organisms. The main focus of endocrine disruption research has centered on how estrogenic and androgenic compounds interact with the endocrine system to elicit reproductive effects. Other classes of compounds, such as progestins, have been overlooked. Recently, studies have investigated the potential for synthetic progestins to impair reproduction and growth in aquatic organisms. The present study utilizes the OECD 210 Early-life Stage (ELS) study to investigate the impacts levonorgestrel (LNG), a synthetic progestin, on fathead minnow (FHM) survival and growth. After 28 days post-hatch, survival of larval FHM was impacted at 462 ng/L, while growth was significantly reduced at 86.9 ng/L. Further analysis was conducted by measuring specific endocrine related mRNA transcript profiles in FHM larvae following the 28 day ELS exposure to LNG. Transcripts of 3β-HSD, 20β-HSD, CYP17, AR, ERα, and FSH were significantly down-regulated following 28d exposure to 16.3 ng/L LNG, while exposure to 86.9 ng/L significantly down-regulated 3β-HSD, 20β-HSD, CYP19A, and FSH. At 2,392 ng/L of LNG, a significant down-regulation occurred with CYP19A and ERβ transcripts, while mPRα and mPRβ profiles were significantly induced. No significant changes occurred in 11β-HSD, CYP11A, StAR, LHβ, and VTG mRNA expression following LNG exposure. An ex vivo steroidogenesis assay was conducted with sexually mature female FHM following a 7 day exposure 100 ng/L LNG with significant reductions observed in pregnenolone, 17α,20β-dihydroxy-4-pregnen-3-one (17,20-DHP), testosterone, and 11-ketotestosterone. Together these data suggest LNG can negatively impact FHM larval survival and growth, with significant alterations in endocrine related responses. PMID:24503577

  11. Oral Exposure of PBDE-47 in Fish: Toxicokinetics and Reproductive Effects in Japanese Medaka (Oryzias latipes) and Fathead Minnows (Pimephales promelas)

    SciTech Connect

    Muirhead, Elisabeth K.; Skillman, Ann D.; Hook, Sharon E.; Schultz, Irv R.

    2006-01-15

    The toxicokinetics of 2,2,4,4-tetrabromodipohenyl ether (PBDE-47) was studied in the Japanese Medaka (Oryzias latipes) after a single oral exposure followed by termination at specific time points. The effects of repeated oral exposure to PBDE-47 on reproductive performance was assessed using a pair breeding experimental design with fathead minnows (Pimephales promelas) given daily PBDE-47 exposures for 25 days, during which fecundity was measured as an indicator of reproductive performance. Medaka and fathead minnows were orally exposed to PBDE-47 by bioencapsulation in brine shrimp, Artemia sp. In the medaka studies, measurable levels of PBDE-47 were detected in the carcass within 0.25 hr with peak levels occurring at 8 hrs. The body levels of PBDE-47 slowly declined and were still 25% of peak levels at 624 hrs after dosing. Assimilation of the bioencapsulated dose was at least 80% and may well approach 100 %. The PBDE-47 concentration-time profile was fitted to a one-compartment clearance-volume toxicokinetic model and the model-predicted values for elimination half-life was determined to be 281 hrs and the first order absorption rate constant was (Ka) = 0.26 hr 1. In the fathead minnow study, egg laying in the PBDE-treated breeding pairs stopped after 10 days. The condition factor of PBDE-treated males was significantly reduced (P < 0.011) compared with control males, whereas no significant difference was observed in females. Histological examination revealed a greater than 50% reduction in mature sperm in PBDE-47 exposed minnows compared to controls. Collectively, these results suggest PBDE-47 is selectively toxic to sexually mature male fathead minnows.

  12. Effect of acclimation period on the relationship of acute copper toxicity to water hardness for fathead minnows

    SciTech Connect

    Erickson, R.J.; Kleiner, C.F.; Fiandt, J.T.; Highland, T.L.

    1997-04-01

    The acute toxicity of copper sulfate to fathead minnows was tested in a 2 x 2 factorial experiment, with factors being low and high water hardness during an acclimation period and low and high hardness during the exposure period. Acclimation hardness was found to have no significant effects on copper lethality, except that the 24-h LC50 at high exposure hardness was 44% higher for fish subject to low acclimation hardness than fish subject to high acclimation hardness. In contrast, exposure hardness was found to have major effects, with LC50s being two or three times greater at high exposure hardness than at low, regardless of the acclimation hardness. These results suggest that the extent of the acclimation period is not a general, severely confounding factor for previous reports of the effects of hardness on copper toxicity to fish, although it may assume some importance for some species and test conditions.

  13. The effects of sub-lethal salinity concentrations on the anti-predator responses of fathead minnows.

    PubMed

    Hoover, Zachary; Ferrari, Maud C O; Chivers, Douglas P

    2013-01-01

    Salinization, both natural and anthropogenic, of inland waters is a major facet of environmental change, and can have detrimental effects on aquatic systems. Fish facing increasing levels of salinity must do more than simply survive salinization, they must also undertake important behaviours such as predator avoidance. Here, we exposed fathead minnows (Pimephales promelas) to three levels of salinity crossed by three levels of predation risk cues. We found a reduction in pre-stimulus movement and a lowered intensity of anti-predator response for the highest salinity exposure (8000 ppm). We also found that the typical threat-sensitive anti-predator response (an important behaviour conferring fitness advantages) was absent in the two highest salinity exposure treatments. Our data demonstrate that salinization can have negative effects on critical behaviours well below physiological tolerance levels.

  14. Transcriptional and physiological response of fathead minnows (Pimephales promelas) exposed to urban waters entering into wildlife protected areas.

    PubMed

    Rodriguez-Jorquera, Ignacio A; Kroll, Kevin J; Toor, Gurpal S; Denslow, Nancy D

    2015-04-01

    The mission of protected areas is to conserve biodiversity and improve human welfare. To assess the effect of urban waters entering into protected areas, we performed 48-h whole-effluent exposures with fathead minnows, analyzing changes in steady state levels of mRNAs in the livers of exposed fish. Raw wastewater, treated city wastewater, and treated wastewater from a university were collected for exposures. All exposed fish showed altered mRNA levels of DNA damage-repair genes. Fish exposed to raw and treated wastewaters showed down-regulation of transcripts for key intermediates of cholesterol biosynthesis and elevated plasma cholesterol. The type of wastewater treatment influenced the response of gene transcription. Because of the relevance of some of the altered cellular pathways, we suggest that these effluents may cause deleterious effects on fish inside protected areas that receive these waters. Inclusion of research and mitigation efforts for this type of threat in protected areas management is advised. PMID:25656232

  15. Environmental effects of dredging. Relationship between pcb tissue residues and reproductive success of fathead minnows. Technical notes

    SciTech Connect

    1988-04-01

    This technical note provides initial guidance for interpreting the biological consequences of bioaccumulation in aquatic organisms. Specifically, the relationship between polychlorinated biphenyl (PCB) tissue residues and reproductive success in the fathead minnow, Pimephales promelas, is examined. The US Army Corps of Engineers often conducts, or requires to be conducted, an assessment of potential bioaccumulation of environmental contaminants from sediments scheduled for dredging and open-water disposal. At present, however, there is no generally accepted guidance to assist in the interpretation of the biological consequences of specific levels of bioacumulation. To provide an initial basis for such guidance, the Environmental Laboratory of the US Army Engineer Waterways Experiment Station is conducting both literature data base analyses and experimental laboratory studies as part of its Long-Term Effects of Dredging Operations (LEDO) Program. This technical note discusses a portion of the laboratory effort.

  16. Bioaccumulation of benzo(a)pyrene from sediment by fathead minnows: Effects of organic content, resuspension, and metabolism

    SciTech Connect

    McCarthy, J.F.; Burrus, L.W.; Tolbert, V.R. )

    1990-01-01

    It is the objective of this research to examine the interaction of chemical and biological variables that influence the uptake and accumulation of a model contaminant, BaP, by the fathead minnow, Pimephales promelas. Specifically, we examine effects of the organic carbon content (OC) of the sediment on partitioning of BaP into the water and on the rate of ingestion of contaminated sediment, the effect of bioturbation of sediment by fish on the aqueous concentration of BaP in the water column, and the apparent increase in the rate of elimination of BaP in fish receiving higher levels of exposure to BaP from sediment and water.

  17. Accumulation and Debromination of Decabromodiphenyl Ether (BDE-209) in Juvenile Fathead Minnows (Pimephales promelas) Induces Thyroid Disruption and Liver Alterations

    PubMed Central

    Noyes, Pamela D.; Hinton, David E.; Stapleton, Heather M.

    2011-01-01

    Polybrominated diphenyl ether (PBDE) flame retardants are known to affect thyroid hormone (TH) regulation. The TH-regulating deiodinases have been implicated in these impacts; however, PBDE effects on the fish thyroid system are largely unknown. Moreover, the liver as a potential target of PBDE toxicity has not been explored in young fish. This study measured decabromodiphenyl ether (BDE-209) effects on TH regulation by measuring deiodinase activity in juvenile fathead minnows (Pimephales promelas). Dietary accumulations and debromination of BDE-209 were also measured, and the morphology of thyroid and liver tissues was examined. Juvenile fathead minnows (28 days old) received a 28-day dietary treatment of BDE-209 at 9.8 ± 0.16 μg/g of food at 5% of their body weight per day followed by a 14-day depuration period in which they were fed clean food. Chemical analysis revealed that BDE-209 accumulated in tissues and was metabolized to reductive products ranging from penta- to octaBDEs with 2,2′,4,4′,5,6′-hexabromodiphenyl ether (BDE-154) being the most accumulative metabolite. By day 28 of the exposure, rates of outer and inner ring deiodination (ORD and IRD, respectively) of thyroxine (T4) were each reduced by ∼74% among treatments. Effects on T4-ORD and T4-IRD remained significant even after the 14-day depuration period. Histological examination of treated fish showed significantly increased thyroid follicular epithelial cell heights and vacuolated hepatocyte nuclei. Enlarged biliary passageways may be the cause of the distinctive liver phenotype observed, although further testing is needed. Altogether, these results suggest that juvenile fish may be uniquely susceptible to thyroid disruptors like PBDEs. PMID:21546348

  18. Altered gene expression in the brain and liver of female fathead minnows Pimephales promelas Rafinesque exposed to fadrozole

    SciTech Connect

    Villeneuve, Daniel L.; Knoebl, Iris; Larkin, Patrick; Miracle, Ann L.; Carter, Barbara J.; Denslow, Nancy D.; Ankley, Gerald T.

    2008-06-01

    The fathead minnow (Pimephales promelas) is a small fish species widely used for ecotoxicology research and regulatory testing in North America. This study used a novel 2000 gene oligonucleotide microarray to evaluate the effects of the aromatase inhibitor, fadrozole, on gene expression in the liver and brain tissue of exposed females. Exposure to 60 μg 1-1 fadrozole/L for 7 d, resulted in the significant (p<0.05; high-moderate agreement among multiple probes spotted on the array) up-regulation of approximately 47 genes in brain and 188 in liver, and the significant down-regulation of 61 genes in brain and 162 in liver. In particular, fadrozole exposure elicited significant up-regulation of five genes in brain involved in the cholesterol synthesis pathway and altered the expression of over a dozen cytoskeleton-related genes. In the liver, there was notable down-regulation of genes coding for vitellogenin precursors, vigillin, and fibroin-like ovulatory proteins which were consistent with an expected reduction in plasma estradiol concentrations as a result of fadrozole exposure and an associated reduction in measured plasma vitellogenin concentrations. These changes coincided with a general down-regulation of genes coding for non-mitochondrial ribosomal proteins and proteins that play a role in translation. With the exception of the fibroin-like ovulatory proteins, real-time PCR results largely corroborated the microarray responses. Overall, results of this study demonstrate the utility of high density oligonucleotide microarrays for unsupervised, discovery-driven, ecotoxicogenomics research with the fathead minnow and helped inform the subsequent development of a 22,000 gene microarray for the species.

  19. Effects of two fungicides with multiple modes of action on reproductive endocrine function in the fathead minnow (Pimephales promelas).

    PubMed

    Ankley, Gerald T; Jensen, Kathleen M; Durhan, Elizabeth J; Makynen, Elizabeth A; Butterworth, Brian C; Kahl, Michael D; Villeneuve, Daniel L; Linnum, Ann; Gray, L Earl; Cardon, Mary; Wilson, Vickie S

    2005-08-01

    Many chemicals that adversely affect reproduction and/or development do so through multiple pathways within the reproductive tract and hypothalamic-pituitary-gonadal axis. Notable in this regard are fungicides, such as prochloraz or fenarimol, which in mammals have the potential to impact endocrine function through inhibition of CYP enzymes involved in steroid metabolism, as well as through antagonism of the androgen receptor(s). The objective of our studies was to assess the effects of prochloraz and fenarimol on reproductive endocrine function in a model small fish species, the fathead minnow (Pimephales promelas), using both in vitro and in vivo assays. The two fungicides inhibited in vitro CYP19 aromatase activity in brain and ovarian homogenates from the fish, with prochloraz exhibiting a greater potency than fenarimol. Prochloraz and fenarimol also bound competitively to the cloned fathead minnow androgen receptor expressed in COS-1 cells. The two fungicides significantly reduced fecundity of the fish in a 21-day reproduction assay at water concentrations of 0.1 (prochloraz) and 1.0 (fenarimol) mg/l. The in vivo effects of prochloraz on plasma steroid (17beta-estradiol, testosterone, 11-ketotestosterone) and vitellogenin (an estrogen-responsive protein) concentrations, as well as on gonadal histopathology, were consistent with inhibition of steroidogenesis. Fenarimol also affected several aspects of endocrine function in vivo; however, the suite of observed effects did not reflect either aromatase inhibition or androgen receptor antagonism. These studies contribute to a better mechanistic understanding of the extrapolation of effects of endocrine-disrupting chemicals across vertebrate classes.

  20. Statistical models to predict the toxicity of major ions to Ceriodaphnia dubia, Daphnia magna and Pimephales promelas (fathead minnows)

    SciTech Connect

    Mount, D.R.; Gulley, D.D.; Hockett, J.R.; Garrison, T.D.; Evans, J.M.

    1997-10-01

    Toxicity of fresh waters with high total dissolved solids has been shown to be dependent on the specific ionic composition of the water. To provide a predictive tool to assess toxicity attributable to major ions, the authors tested the toxicity of over 2,900 ion solutions using the daphnids, Ceriodaphnia dubia and Daphnia magna, and fathead minnows (Pimephales promelas). Multiple logistic regression was used to relate ion composition to survival for each of the three test species. In general, relative ion toxicity was K{sup +} > HCO{sub 3}{sup {minus}} {approx} Mg{sup 2+} > Cl{sup {minus}} > SO{sub 4}{sup 2{minus}}; Na{sup +} and Ca{sup 2+} were not significant variables in the regressions, suggesting that the toxicity of Na{sup +} and Ca{sup 2+} salts was primarily attributable to the corresponding anion. For C. dubia and D. magna, toxicity of Cl{sup {minus}}, SO{sub 4}{sup 2{minus}}, and K{sup +} was reduced in solutions enriched with more than one cation. Final regression models showed a good quality of fit to the data (R{sup 2} = 0.767--0.861). Preliminary applications of these models to field-collected samples indicated a high degree of accuracy for the C. dubia model, while the D. magna and fathead minnow models tended to overpredict ion toxicity. Studies of oil and gas produced waters, irrigation drain waters, shale oil leachates, sediment pore waters, and industrial process waters have shown toxicity caused by elevated concentrations of common ions.

  1. 17alpha-ethinylestradiol alters reproductive behaviors, circulating hormones, and sexual morphology in male fathead minnows (Pimephales promelas).

    PubMed

    Salierno, James D; Kane, Andrew S

    2009-05-01

    Ecologically relevant indicators of endocrine disruption in fish must be linked with measures of reproductive success. The ability of male fathead minnows (Pimephales promelas) to compete for, maintain, and defend a spawning substrate is paramount to reproductive success. The present study quantified alterations in male fathead minnow reproductive behaviors after exposure to environmentally relevant concentrations (0, 10, 20, or 40 ng/L) of 17alpha-ethinylestradiol (EE2) for 21 d. A video-based behavioral quantification system examined changes in male-male competitive behaviors (chasing and head-butting) and ability of males to maintain spawning substrates (nibbling and scrubbing). Behaviors analyzed included time under the spawning substrate, frequency of substrate cleaning, and conspecific aggression. Plasma hormone levels (11-ketotestosterone [11-KT], testosterone, and estradiol [E2]), vitellogenin (VTG), secondary male characteristics (tubercle count and dorsal nape pad rank), gonadosomatic index (GSI), and gonad histology also were evaluated. Exposure to 40 ng/L of EE2 decreased the ability of exposed males to compete with control males for spawning substrates (p = 0.09). Furthermore, exposed males displayed reduced frequency of substrate cleaning activities as well as chasing male competitors (p < or = 0.05). 11-Ketotestosterone, testosterone, and E2 were lower, and VTG was notably higher, in EE2-exposed males compared with control males (p < or = 0.03). 17alpha-Ethinylestradiol exposure in males also was associated with reductions in tubercles; lower GSI, gonadal maturity ranks, and number of resorbed tubercles; and presence of an ovipositor (p < or = 0.001). These data reveal alterations in male reproductive behavior that coincide with decreased hormone levels and secondary sex characteristics. Behavioral endpoints to discern potential ecological consequences in fish exposed to low concentrations of endocrine-disrupting chemicals may provide sensitive and

  2. In Silico analysis of perturbed steroidogenesis and gonad growth in fathead minnows (P. promelas) exposed to 17α-ethynylestradiol.

    PubMed

    Hala, David; Petersen, Lene H; Martinović, Dalma; Huggett, Duane B

    2015-06-01

    The multi-factorial nature of adverse reproductive effects mediated by endocrine disrupting compounds (or EDCs) makes understanding the mechanistic basis of reproductive dysfunction a highly pertinent area of research. As a consequence, a main motivator for continued research is to integrate 'multi-leveled' complexity (i.e., from genes to phenotype) using mathematical methods capable of encapsulating properties of physiological relevance. In this study, an in silico stoichiometric model of piscine steroidogenesis was augmented with a 'biomass' reaction associating the underlying stoichiometry of steroidogenesis with a reaction representative of gonad growth. The ability of the in silico model to predict perturbed steroidogenesis and subsequent effects on gonad growth was tested by exposing reproductively active male and female fathead minnows (Pimephales promelas) to 88 ng/L of the synthetic estrogen, 17α-ethynylestradiol (EE2). The in silico model was parameterized (or constrained) with experimentally quantified concentrations of selected steroid hormones (using mass spectrometry) and fold changes in gene expression (using RT-qPCR) for selected steroidogenic enzyme genes, in gonads of male and female fish. Once constrained, the optimization framework of flux balance analysis (FBA) was used to calculate an optimal flux through the biomass reaction (analogous to gonad growth) and associated steroidogenic flux distributions required to generate biomass. FBA successfully predicted effects of EE2 exposure on fathead minnow gonad growth (%gonadosomatic index or %GSI) and perturbed production of steroid hormones. Specifically, FBA accurately predicted no effects of exposure on male %GSI and a significant reduction for female %GSI. Furthermore, in silico simulations accurately identified disrupted reaction fluxes catalyzing productions of androgens (in male fish) and progestogens (in female fish), an observation which agreed with in vivo experimentation. The analyses

  3. Static renewal tests using Pimephales promelas (fathead minnows). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    SciTech Connect

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21--28, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  4. Reproductive responses of male fathead minnows exposed to wastewater treatment plant effluent, effluent treated with XAD8 resin, and an environmentally relevant mixture of alkylphenol compounds

    USGS Publications Warehouse

    Barber, L.B.; Lee, K.E.; Swackhamer, D.L.; Schoenfuss, H.L.

    2007-01-01

    On-site, continuous-flow experiments were conducted during August and October 2002 at a major metropolitan wastewater treatment plant (WWTP) to determine if effluent exposure induced endocrine disruption as manifested in the reproductive competence of sexually mature male fathead minnows (Pimephales promelas). The fathead minnows were exposed in parallel experiments to WWTP effluent and WWTP effluent treated with XAD8 macroreticular resin to remove the hydrophobic-neutral fraction which contained steroidal hormones, alkylphenolethoxylates (APEs), and other potential endocrine disrupting compounds (EDCs). The effluent composition varied on a temporal scale and the continuous-flow experiments captured the range of chemical variability that occurred during normal WWTP operations. Exposure to WWTP effluent resulted in vitellogenin induction in male fathead minnows, with greater response in October than in August. Concentrations of ammonia, APEs, 17??-estradiol, and other EDCs also were greater in October than in August, reflecting a change in effluent composition. In the October experiment, XAD8 treatment significantly reduced vitellogenin induction in the male fathead minnows relative to the untreated effluent, whereas in August, XAD8 treatment had little effect. During both experiments, XAD8 treatment removed greater than 90% of the APEs. Exposure of fish to a mixture of APEs similar in composition and concentration to the WWTP effluent, but prepared in groundwater and conducted at a separate facility, elicited vitellogenin induction during both experiments. There was a positive relation between vitellogenin induction and hepatosomatic index (HSI), but not gonadosomatic index (GSI), secondary sexual characteristics index (SSCI), or reproductive competency. In contrast to expectations, the GSI and SSCI increased in males exposed to WWTP effluent compared to groundwater controls. The GSI, SSCI, and reproductive competency were positively affected by XAD8 treatment of

  5. Development of quantitative real-time PCR assays for fathead minnow (Pimephales promelas) gonadotropin ß subunit mRNAs to support endocrine disruptor research.

    SciTech Connect

    Villeneuve, Daniel L.; Miracle, Ann L.; Jensen, Kathleen M.; Degitz, Sigmund J.; Kahl, Michael D.; Korte, Joseph J.; Greene, Katie J.; Blake, Lindsey S.; Linnum, Ann; Ankley, Gerald T.

    2007-03-01

    Fathead minnows (Pimephales promelas) are one of the most widely-used small fish models for regulatory ecotoxicology testing and research related to endocrine disrupting chemicals (EDCs). In this study, we isolated and sequenced cDNAs for fathead minnow follicle-stimulating hormone-like and luteinizing hormone-like β (FSHβ and LHβ) and glycoprotein α (GPα) subunits. Quantitative real-time PCR assays for measuring gonadotropin (GtH) β subunit transcripts were developed and used to examine “baseline” transcript levels over a range of age classes and reproductive states encompassed in EDC testing. In females, FSHβ and LHβ transcripts were greater in 4-5 month old than in younger fish and were significantly correlated with one another across all age classes examined. In males, FSHβ transcripts were greatest in 2-3 month old fish and were inversely correlated with various measures of testis development including, gonadal-somatic index (GSI), and histological stage. Overall, the pattern of GtHβ expression over age classes associated with gonad development was similar to that reported for other asynchronous-spawning fish. Despite significant changes in female GSI, gonad stage, and plasma vitellogenin within 24 h of spawning, GtHβ transcript levels in fish that had spawned within the preceding 24 h were not significantly different from those in fish that were 2-3 days post-spawn and expected to spawn within the next 24 h based on spawning history. Results of this study provide insights related to the role of GtHs in fathead minnow reproductive development and function. Additionally they provide useful “baseline” data needed to design and interpret effective experiments for studying direct and indirect effects of EDCs on GtH subunit mRNA expression, which will facilitate a greater understanding of integrated system-wide responses of the fathead minnow brain-pituitary-gonadal axis to stressors including EDCs.

  6. Time-specific and population-level differences in physiological responses of fathead minnows (Pimephales promelas) and golden shiners (Notemigonus crysoleucas) exposed to copper.

    PubMed

    Peles, John D; Pistole, David H; Moffe, Mickey C

    2012-03-01

    The influence of exposure time on gill Na+/K+ ATPase activity and metabolic rate in populations of fathead minnows (Pimephales promelas) and golden shiners (Notemigonus crysoleucas) hatcheries in Ohio (OH) and Pennsylvania (PA) when exposed to sublethal concentrations of copper (Cu) was examined. The pattern of change in gill Na+/K+ ATPase activity was similar in all species/populations and results support expectations based on the concept of acclimation. In all populations, Na+/K+ ATPase activity declined significantly compared to reference values within 24 h, recovered by 48 h, and then continued to increase before exceeding reference values by 192 h. With the exception of PA fathead minnows, Na+/K+ ATPase activities returned to reference levels by 384 h. Although metabolic rates of individual fish were not strongly correlated with Na+/K+ ATPase activities, the pattern of change in mean values of these physiological parameters was very similar. However, OH populations of both fathead minnows and golden shiners demonstrated much more dramatic changes in metabolic rate compared to PA fish. At 24 h, metabolic rate of PA fathead minnows had decreased by 16% compared to the reference value whereas the OH population had decreased by 31%; metabolic rate of PA golden shiners declined by 23% compared to 59% in OH shiners at 24 h. Similar differences were observed in the maximum metabolic rates achieved at 192 h. While the increased sensitivity of OH fish to Cu is not readily explainable by genetic or environmental factors, results suggest the need for considering population level differences when evaluating the physiological effects of toxicants.

  7. Uptake and tissue distribution of waterborne [{sup 3}H]-2,3,7,8-tetrachlorodibenzo-p-dioxin in embryonic fathead minnow (Pimephales promelas)

    SciTech Connect

    Winden, P.J.J. de; Herwig, H.J.

    1995-12-31

    Accumulation of [{sup 3}H]tetrachlorodibenzo-p-dioxin ([{sup 3}H]-TCDD) was studied in embryos of fathead minnow (Pimephales promelas), to evaluate this species` high sensitivity to this compound in relation to internal concentrations. Pathological alterations during fathead minnow early development were described previously at aqueous concentrations ranging from 0.1--50 ng/l. Fertilized eggs and developing embryos were exposed to [{sup 3}H]TCDD (32 mCi/{micro}mol) in 100 ml of water (24 hour static-renewal procedure), until onset of hatch. With 24 hour intervals, radioactivity was measured in exposure water and embryos using liquid scintillation counting. Radioactivity in embryonic tissue was determined in whole body homogenates, obtained by extraction with Lumasolve. Collection of outcoming air from the ventilated exposure medium in aceton revealed no loss of TCDD as a result of evaporation. Binding of TCDD to glass, however, appeared considerable and highly variable (25--50% after 24 hrs). [{sup 3}H]-TCDD levels in exposure water declined from 10 ng/l to < 1 ng/l in 24 hrs (reduction of 85--90%). Fathead minnow eggs or embryos (N = 60), exposed to an initial level of 10 ng [{sup 3}H]TCDD/l, accumulated approximately 3--15% of the applied toxicant in a 24 hr period. During 5 days of exposure (daily medium refreshment), uptake of TCDD increased linearly from 1--2 pg/embryo (day 1) to 9--10 pg/embryo (day 5). Hatching took place in fresh water, resulting in some elimination of TCDD to a level of 6--7 pg/embryo at day 6. The present data demonstrate high toxicity of TCDD in fathead minnow early life stages. At day 3 of embryonic development, accumulation of 5--7 pg [{sup 3}H]-TCDD per embryo causes severe hemodynamic disturbances. Microautoradiography is currently applied to study tissue distribution of [{sup 3}H]-TCDD during embryogenesis.

  8. Reproductive responses of male fathead minnows exposed to wastewater treatment plant effluent, effluent treated with XAD8 resin, and an environmentally relevant mixture of alkylphenol compounds.

    PubMed

    Barber, Larry B; Lee, Kathy E; Swackhamer, Deborah L; Schoenfuss, Heiko L

    2007-04-20

    On-site, continuous-flow experiments were conducted during August and October 2002 at a major metropolitan wastewater treatment plant (WWTP) to determine if effluent exposure induced endocrine disruption as manifested in the reproductive competence of sexually mature male fathead minnows (Pimephales promelas). The fathead minnows were exposed in parallel experiments to WWTP effluent and WWTP effluent treated with XAD8 macroreticular resin to remove the hydrophobic-neutral fraction which contained steroidal hormones, alkylphenolethoxylates (APEs), and other potential endocrine disrupting compounds (EDCs). The effluent composition varied on a temporal scale and the continuous-flow experiments captured the range of chemical variability that occurred during normal WWTP operations. Exposure to WWTP effluent resulted in vitellogenin induction in male fathead minnows, with greater response in October than in August. Concentrations of ammonia, APEs, 17beta-estradiol, and other EDCs also were greater in October than in August, reflecting a change in effluent composition. In the October experiment, XAD8 treatment significantly reduced vitellogenin induction in the male fathead minnows relative to the untreated effluent, whereas in August, XAD8 treatment had little effect. During both experiments, XAD8 treatment removed greater than 90% of the APEs. Exposure of fish to a mixture of APEs similar in composition and concentration to the WWTP effluent, but prepared in groundwater and conducted at a separate facility, elicited vitellogenin induction during both experiments. There was a positive relation between vitellogenin induction and hepatosomatic index (HSI), but not gonadosomatic index (GSI), secondary sexual characteristics index (SSCI), or reproductive competency. In contrast to expectations, the GSI and SSCI increased in males exposed to WWTP effluent compared to groundwater controls. The GSI, SSCI, and reproductive competency were positively affected by XAD8 treatment of

  9. Short-term fish reproduction assays with methyl tertiary butyl ether with zebrafish and fathead minnow: Implications for evaluation of potential for endocrine activity.

    PubMed

    Mihaich, Ellen; Erler, Steffen; Le Blanc, Gerald; Gallagher, Sean

    2015-09-01

    The authors report on short-term fish reproduction assays in zebrafish and fathead minnow conducted to examine the potential for methyl tertiary butyl ether (MTBE) to cause effects on the endocrine system. Both studies were performed under good laboratory practice and in accordance with Organisation for Economic Co-operation and Development and US Environmental Protection Agency test guidelines. The results of the first study demonstrated that exposure to a high test concentration (147 mg/L) of MTBE impaired reproductive output of female zebrafish, evident by a reduction in fecundity. Based on the endpoints evaluated in the present study however, there was no supporting evidence to indicate that this effect was caused by disruption of or interaction with the endocrine system. In the second study, fathead minnows exposed to a wider but lower range of test concentrations showed no effects on any reproductive parameter of male or female fish, at the maximum recommended testing concentration of 100 mg/L (62 mg/L measured). The results of these 2 guideline studies indicate that MTBE does not interact with the hypothalamic-pituitary-gonadal axis of zebrafish or fathead minnow. PMID:25866897

  10. Short-term fish reproduction assays with methyl tertiary butyl ether with zebrafish and fathead minnow: Implications for evaluation of potential for endocrine activity.

    PubMed

    Mihaich, Ellen; Erler, Steffen; Le Blanc, Gerald; Gallagher, Sean

    2015-09-01

    The authors report on short-term fish reproduction assays in zebrafish and fathead minnow conducted to examine the potential for methyl tertiary butyl ether (MTBE) to cause effects on the endocrine system. Both studies were performed under good laboratory practice and in accordance with Organisation for Economic Co-operation and Development and US Environmental Protection Agency test guidelines. The results of the first study demonstrated that exposure to a high test concentration (147 mg/L) of MTBE impaired reproductive output of female zebrafish, evident by a reduction in fecundity. Based on the endpoints evaluated in the present study however, there was no supporting evidence to indicate that this effect was caused by disruption of or interaction with the endocrine system. In the second study, fathead minnows exposed to a wider but lower range of test concentrations showed no effects on any reproductive parameter of male or female fish, at the maximum recommended testing concentration of 100 mg/L (62 mg/L measured). The results of these 2 guideline studies indicate that MTBE does not interact with the hypothalamic-pituitary-gonadal axis of zebrafish or fathead minnow.

  11. Estimating the effects of 17α-ethinylestradiol on stochastic population growth rate of fathead minnows: a population synthesis of empirically derived vital rates.

    PubMed

    Schwindt, Adam R; Winkelman, Dana L

    2016-09-01

    Urban freshwater streams in arid climates are wastewater effluent dominated ecosystems particularly impacted by bioactive chemicals including steroid estrogens that disrupt vertebrate reproduction. However, more understanding of the population and ecological consequences of exposure to wastewater effluent is needed. We used empirically derived vital rate estimates from a mesocosm study to develop a stochastic stage-structured population model and evaluated the effect of 17α-ethinylestradiol (EE2), the estrogen in human contraceptive pills, on fathead minnow Pimephales promelas stochastic population growth rate. Tested EE2 concentrations ranged from 3.2 to 10.9 ng L(-1) and produced stochastic population growth rates (λ S ) below 1 at the lowest concentration, indicating potential for population decline. Declines in λ S compared to controls were evident in treatments that were lethal to adult males despite statistically insignificant effects on egg production and juvenile recruitment. In fact, results indicated that λ S was most sensitive to the survival of juveniles and female egg production. More broadly, our results document that population model results may differ even when empirically derived estimates of vital rates are similar among experimental treatments, and demonstrate how population models integrate and project the effects of stressors throughout the life cycle. Thus, stochastic population models can more effectively evaluate the ecological consequences of experimentally derived vital rates. PMID:27372448

  12. Predator avoidance performance of larval fathead minnows (Pimephales promelas) following short-term exposure to estrogen mixtures

    USGS Publications Warehouse

    McGee, M.R.; Julius, M.L.; Vajda, A.M.; Norris, D.O.; Barber, L.B.; Schoenfuss, H.L.

    2009-01-01

    Aquatic organisms exposed to endocrine disrupting compounds (EDCs) at early life-stages may have reduced reproductive fitness via disruption of reproductive and non-reproductive behavioral and physiological pathways. Survival to reproductive age relies upon optimal non-reproductive trait expression, such as adequate predator avoidance responses, which may be impacted through EDC exposure. During a predator–prey confrontation, larval fish use an innate C-start escape behavior to rapidly move away from an approaching threat. We tested the hypotheses that (1) larval fathead minnows exposed to estrogens, a primary class of EDCs, singularly or in mixture, suffer a reduced ability to perform an innate C-start behavior when faced with a threat stimulus; (2) additive effects will cause greater reductions in C-start behavior; and (3) effects will differ among developmental stages. In this study, embryos (post-fertilization until hatching) were exposed for 5 days to environmentally relevant concentrations of estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2) singularly and in mixture. Exposed embryos were allowed to hatch and grow in control well water until 12 days old. Similarly, post-hatch fathead minnows were exposed for 12 days to these compounds. High-speed (1000 frames/s) video recordings of escape behavior were collected and transferred to National Institutes of Health Image for frame-by-frame analysis of latency period, escape velocity, and total escape response (combination of latency period and escape velocity). When tested 12 days post-hatch, only E1 adversely affected C-start performance of larvae exposed as embryos. Conversely, larvae exposed for 12 days post-hatch did not exhibit altered escape responses when exposed to E1, while adverse responses were seen in E2 and the estrogen mixture. Ethinylestradiol exposure did not elicit changes in escape behaviors at either developmental stage. The direct impact of reduced C-start performance on

  13. Impaired anterior swim bladder inflation following exposure to the thyroid peroxidase inhibitor 2-mercaptobenzothiazole part I: Fathead minnow.

    PubMed

    Nelson, Krysta R; Schroeder, Anthony L; Ankley, Gerald T; Blackwell, Brett R; Blanksma, Chad; Degitz, Sigmund J; Flynn, Kevin M; Jensen, Kathleen M; Johnson, Rodney D; Kahl, Michael D; Knapen, Dries; Kosian, Patricia A; Milsk, Rebecca Y; Randolph, Eric C; Saari, Travis; Stinckens, Evelyn; Vergauwen, Lucia; Villeneuve, Daniel L

    2016-04-01

    In the present study, a hypothesized adverse outcome pathway linking inhibition of thyroid peroxidase (TPO) activity to impaired swim bladder inflation was investigated in two experiments in which fathead minnows (Pimephales promelas) were exposed to 2-mercaptobenzothiazole (MBT). Continuous exposure to 1mg MBT/L for up to 22 days had no effect on inflation of the posterior chamber of the swim bladder, which typically inflates around 6 days post fertilization (dpf), a period during which maternally-derived thyroid hormone is presumed to be present. In contrast, inflation of the anterior swim bladder, which occurs around 14dpf, was impacted. Specifically, at 14dpf, approximately 50% of fish exposed to 1mg MBT/L did not have an inflated anterior swim bladder. In fish exposed to MBT through 21 or 22dpf, the anterior swim bladder was able to inflate, but the ratio of the anterior/posterior chamber length was significantly reduced compared to controls. Both abundance of thyroid peroxidase mRNA and thyroid follicle histology suggest that fathead minnows mounted a compensatory response to the presumed inhibition of TPO activity by MBT. Time-course characterization showed that fish exposed to MBT for at least 4 days prior to normal anterior swim bladder inflation had significant reductions in anterior swim bladder size, relative to the posterior chamber, compared to controls. These results, along with similar results observed in zebrafish (see part II, this issue) are consistent with the hypothesis that thyroid hormone signaling plays a significant role in mediating anterior swim bladder inflation and development in cyprinids, and that role can be disrupted by exposure to thyroid hormone synthesis inhibitors. Nonetheless, possible thyroid-independent actions of MBT on anterior swim bladder inflation cannot be ruled out based on the present results. Overall, although anterior swim bladder inflation has not been directly linked to survival as posterior swim bladder inflation

  14. Influence of bicarbonate and humic acid on effects of chronic waterborne lead exposure to the fathead minnow (Pimephales promelas).

    PubMed

    Mager, Edward M; Brix, Kevin V; Grosell, Martin

    2010-01-31

    Historically, the USEPA has only considered water hardness when establishing acute and chronic water quality criteria (WQC) for lead (Pb) in freshwater. Yet, recent evidence suggests that hardness may not be protective during chronic Pb exposure and that other factors (e.g., dissolved organic carbon (DOC) and alkalinity) influence toxicity. In fact, we have recently shown that Ca(2+) (as CaSO(4)) does not protect against Pb accumulation in fathead minnows (Pimephales promelas) during chronic exposures whereas DOC as humic acid (HA) clearly does. To more clearly define the water chemistry parameters mediating chronic Pb toxicity we carried out 300 d exposures to study the influence of DOC and alkalinity on Pb accumulation and toxicity to fathead minnows at 2 different Pb concentrations (170 and 580 nM (35 and 120 microg/L)). Alkalinity was adjusted by addition of 500 microM NaHCO(3) and DOC by addition of 4 mg/L HA. Fish were collected at 4, 30, 150 and 300 d of exposure to measure growth and Pb accumulation. Breeding assays (21 d) were performed at the end of these exposures to assess reproductive and larval behavioral endpoints. To determine whether effects were acute or chronic, switched breeding exposures were performed in which control breeders were transferred to either high or low Pb conditions and Pb-exposed breeders transferred to tap water without Pb. Mortality and growth effects were observed primarily in the high Pb treatments and within the first 10 d of exposure. Strong protection against Pb accumulation was afforded by increased DOC at both Pb concentrations. Increased alkalinity also appeared to moderately reduce Pb accumulation although not to the level of statistical significance. Tissue distribution of Pb was analyzed at 300 d and was found to accumulate mostly in bone, gill, intestine and kidney. Unexpectedly, high Pb reduced total reproductive output and increased average egg mass in the HCO(3)(-) and DOC treatments but not in the control water

  15. Impaired anterior swim bladder inflation following exposure to the thyroid peroxidase inhibitor 2-mercaptobenzothiazole part I: Fathead minnow.

    PubMed

    Nelson, Krysta R; Schroeder, Anthony L; Ankley, Gerald T; Blackwell, Brett R; Blanksma, Chad; Degitz, Sigmund J; Flynn, Kevin M; Jensen, Kathleen M; Johnson, Rodney D; Kahl, Michael D; Knapen, Dries; Kosian, Patricia A; Milsk, Rebecca Y; Randolph, Eric C; Saari, Travis; Stinckens, Evelyn; Vergauwen, Lucia; Villeneuve, Daniel L

    2016-04-01

    In the present study, a hypothesized adverse outcome pathway linking inhibition of thyroid peroxidase (TPO) activity to impaired swim bladder inflation was investigated in two experiments in which fathead minnows (Pimephales promelas) were exposed to 2-mercaptobenzothiazole (MBT). Continuous exposure to 1mg MBT/L for up to 22 days had no effect on inflation of the posterior chamber of the swim bladder, which typically inflates around 6 days post fertilization (dpf), a period during which maternally-derived thyroid hormone is presumed to be present. In contrast, inflation of the anterior swim bladder, which occurs around 14dpf, was impacted. Specifically, at 14dpf, approximately 50% of fish exposed to 1mg MBT/L did not have an inflated anterior swim bladder. In fish exposed to MBT through 21 or 22dpf, the anterior swim bladder was able to inflate, but the ratio of the anterior/posterior chamber length was significantly reduced compared to controls. Both abundance of thyroid peroxidase mRNA and thyroid follicle histology suggest that fathead minnows mounted a compensatory response to the presumed inhibition of TPO activity by MBT. Time-course characterization showed that fish exposed to MBT for at least 4 days prior to normal anterior swim bladder inflation had significant reductions in anterior swim bladder size, relative to the posterior chamber, compared to controls. These results, along with similar results observed in zebrafish (see part II, this issue) are consistent with the hypothesis that thyroid hormone signaling plays a significant role in mediating anterior swim bladder inflation and development in cyprinids, and that role can be disrupted by exposure to thyroid hormone synthesis inhibitors. Nonetheless, possible thyroid-independent actions of MBT on anterior swim bladder inflation cannot be ruled out based on the present results. Overall, although anterior swim bladder inflation has not been directly linked to survival as posterior swim bladder inflation

  16. EFFECTS OF HANDLING ON ENDOCRINOLOGY AND REPRODUCTIVE PERFORMANCE OF THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    A short-term (21-d) reproductive toxicity test with the fatheadt minnow (Pimephales promelas) has been proposed as a standard method for identifying certain classes of endocrine-disrupting chemicals (EDCs). A potentially useful route of chemical exposure for the test is intraperi...

  17. Triclosan impairs swimming behavior and alters expression of excitation-contraction coupling proteins in fathead minnow (Pimephales promelas).

    PubMed

    Fritsch, Erika B; Connon, Richard E; Werner, Inge; Davies, Rebecca E; Beggel, Sebastian; Feng, Wei; Pessah, Isaac N

    2013-02-19

    Triclosan (TCS), a high volume chemical widely used in consumer products, is a known aquatic contaminant found in fish inhabiting polluted watersheds. Mammalian studies have recently demonstrated that TCS disrupts signaling between the ryanodine receptor (RyR) and the dihydropyridine receptor (DHPR), two proteins essential for excitation-contraction (EC) coupling in striated muscle. We investigated the swimming behavior and expression of EC coupling proteins in larval fathead minnows (Pimephales promelas) exposed to TCS for up to 7 days. Concentrations as low as 75 μg L(-1) significantly altered fish swimming activity after 1 day; which was consistent after 7 days of exposure. The mRNA transcription and protein levels of RyR and DHPR (subunit CaV1.1) isoforms changed in a dose and time dependent manner. Crude muscle homogenates from exposed larvae did not display any apparent changes in receptor affinity toward known radioligands. In nonexposed crude muscle homogenates, TCS decreased the binding of [(3)H]PN20-110 to the DHPR and decreased the binding of [(3)H]-ryanodine to the RyR, demonstrating a direct impact at the receptor level. These results support TCS's impact on muscle function in vertebrates further exemplifying the need to re-evaluate the risks this pollutant poses to aquatic environments.

  18. Evaluation of potential mechanisms of atrazine-induced reproductive impairment in fathead minnow (Pimephales promelas) and Japanese medaka (Oryzias latipes)

    USGS Publications Warehouse

    Richter, Cathy; Papoulias, Diana M.; Whyte, Jeffrey J.; Tillitt, Donald E.

    2016-01-01

    Atrazine has been implicated in reproductive dysfunction of exposed organisms, and previous studies documented decreased egg production in Japanese medaka (Oryzias latipes) and fathead minnows (Pimephales promelas) during 30-d to 38-d exposures to 0.5 µg/L, 5 µg/L, and 50 µg/L atrazine. The authors evaluated possible mechanisms underlying the reduction in egg production. Gene expression in steroidogenesis pathways and the hypothalamus–pituitary–gonad axis of male and female fish was measured. Atrazine did not significantly induce gonad aromatase (cyp19a1a) expression. An atrazine-induced shift in the number of females in an active reproductive state was observed. Expression of the egg maturation genes vitellogenin 1 (vtg1) and zona pellucida glycoprotein 3.1 (zp3.1) in medaka females was correlated and had a bimodal distribution. In both species, females with low vtg1 or zp3.1 expression also had low expression of steroidogenesis genes in the gonad, estrogen receptor in the liver, and gonadotropins in the brain. In the medaka, the number of females per tank that had high expression of zp3.1 was significantly correlated with egg production per tank. The number of medaka females with low expression of zp3.1 increased significantly with atrazine exposure. Thus, the decline in egg production observed in response to atrazine exposure may be the result of a coordinated downregulation of genes required for reproduction in a subset of females.

  19. The interactive effects of multiple stressors on physiological stress responses and club cell investment in fathead minnows.

    PubMed

    Manek, Aditya K; Ferrari, Maud C O; Niyogi, Som; Chivers, Douglas P

    2014-04-01

    Anthropogenic activities have dramatically increased over the past decades, with the consequence that many organisms are simultaneously exposed to multiple stressors. Understanding how organisms respond to these stressors is a key focus for scientists from many disciplines. Here we investigated the interactive effects of two stressors, UV radiation (UVR) and cadmium (Cd) exposure on a common freshwater fish, fathead minnow (Pimephales promelas). UVR is known to influence the density of epidermal club cells (ECCs), which are not only a key component of the innate immune system of fishes, but are also the source of chemical alarm cues that serve to warn other fishes of nearby predators. In contrast, Cd impairs the physiological stress response and ability of fish to respond to alarm cues. We used an integrative approach to examine physiological stress response as well as investment in ECCs. Fish exposed to UVR had higher levels of cortisol than non-exposed controls, but Cd reduced cortisol levels substantially for fish exposed to UVR. Fish exposed to UVR, either in the presence or absence of Cd, showed consistent decreases in ECC investment compared to non-exposed controls. Despite differences in ECC number, there was no difference in the potency of alarm cues prepared from the skin of UVR and Cd exposed or non-exposed fish indicating that UVR and Cd exposure combined may have little influence on chemically-mediated predator-prey interactions. PMID:24463029

  20. Triclosan impairs swimming behavior and alters expression of excitation-contraction coupling proteins in fathead minnow (Pimephales promelas).

    PubMed

    Fritsch, Erika B; Connon, Richard E; Werner, Inge; Davies, Rebecca E; Beggel, Sebastian; Feng, Wei; Pessah, Isaac N

    2013-02-19

    Triclosan (TCS), a high volume chemical widely used in consumer products, is a known aquatic contaminant found in fish inhabiting polluted watersheds. Mammalian studies have recently demonstrated that TCS disrupts signaling between the ryanodine receptor (RyR) and the dihydropyridine receptor (DHPR), two proteins essential for excitation-contraction (EC) coupling in striated muscle. We investigated the swimming behavior and expression of EC coupling proteins in larval fathead minnows (Pimephales promelas) exposed to TCS for up to 7 days. Concentrations as low as 75 μg L(-1) significantly altered fish swimming activity after 1 day; which was consistent after 7 days of exposure. The mRNA transcription and protein levels of RyR and DHPR (subunit CaV1.1) isoforms changed in a dose and time dependent manner. Crude muscle homogenates from exposed larvae did not display any apparent changes in receptor affinity toward known radioligands. In nonexposed crude muscle homogenates, TCS decreased the binding of [(3)H]PN20-110 to the DHPR and decreased the binding of [(3)H]-ryanodine to the RyR, demonstrating a direct impact at the receptor level. These results support TCS's impact on muscle function in vertebrates further exemplifying the need to re-evaluate the risks this pollutant poses to aquatic environments. PMID:23305567

  1. Precision of the EPA Seven-Day Fathead Minnow Larval Survival and Growth Test: Intra- and interlaboratory study: Final report

    SciTech Connect

    DeGraeve, G.M.; Cooney, J.D.; Pollock, T.L.; Reichenbach, N.G.; Dean, J.H.; Marcus, M.D.; McIntyre, D.O.

    1989-01-01

    The US Environmental Protection Agency (US EPA) has recently developed a ''Seven-Day Fathead Minnow Larval Survival and Growth Test'' for measuring the toxicity of effluents. This study evaluated the intra- and interlaboratory variability of this seven-day test using two reference toxicants (sodium pentachlorophenate and potassium dichromate), two treated refinery effluents, and one untreated internal utility waste stream. Ten different laboratories, representing academia, private industry, contractors, State EPA and US EPA participated in the study. The reference toxicants were tested twice during two separate test periods and each industrial effluent was treated once during a single period. Weight NOEC values were generally similar to those for survival, but had substantially greater variability than survival NOEC values. Increasing the number of replicate test chambers from two to three increased the test sensitivity and decreased the variability in NOEC values. Overall this chronic test procedure was moderately easy to carry-out for experienced laboratories and appears to be a precise method for estimating toxicity. The laboratories were able to successfully complete 126 of 140 tests. Nine of the 14 unsuccessful completed tests were invalid because survival of larvae in control exposures was below the US EPA's survival criterion of 80% for chronic bioassays. 26 refs., 13 figs., 40 tabs.

  2. Subchronic sensitivity of one-, four-, and seven-day-old fathead minnow (Pimephales promelas) larvae to five toxicants

    SciTech Connect

    Pickering, Q.H.; Lazorchak, J.M.; Winks, K.L.

    1996-03-01

    The fathead minnow (Pimephales promelas) larval survival and growth test was used to evaluate the relative sensitivity of 1-, 4-, and 7-d-old larvae to five contaminants, KCl, NaCl, 1-octanol, carbaryl, and benzaldehyde. The no observable effect concentration (NOEC) for survival of the two inorganic compounds, KCl and NaCl, was not affected by age of the larvae. The subchronic valve (SCV) for NaCl was always determined by survival. Hypothesis testing of biomass always gave the same NOEC for the three age groups for each of the two inorganic compounds, and a minimum significant difference (MSD) was always calculable. The effect of 1-octanol on growth was more sensitive than the effect on survival in eight of the nine toxicity tests. Within a set of 1-, 4-, and 7-d-old larvae tests the SCV varied only twofold; however, between sets of tests the variation was fourfold. The SCV of carbaryl was determined by the effect on growth in five of six tests. Except for one test the SCV varied only twofold. The 1-d larvae were more sensitive to benzaldehyde than 1- and 7-d larvae in two sets of tests. The SCV was determined on the basis of survival for 1-d-old larvae and on the basis of growth for 4- and 7-d-old larvae.

  3. Dactylogyrus olfactorius n. sp. (Monogenea, Dactylogyridae) from the olfactory chamber of the fathead minnow, Pimephales promelas Rafinesque (Cyprinidae).

    PubMed

    Lari, Ebrahim; Adams, Rachael V; Cone, David K; Goater, Cameron P; Pyle, Greg G

    2016-07-01

    Dactylogyrus olfactorius n. sp. (Monogenea) is described from the olfactory chamber of the fathead minnow Pimephales promelas Rafinesque in Alberta, Canada. The new species resembles Dactylogyrus bychowskyi Mizelle, 1937, D. bifurcatus Mizelle, 1937 and D. simplexus Mizelle, 1937, all parasites of Pimephales spp. in North America, in overall size and shape of the anchors and hooks, and in having a male copulatory complex with a tapered tubular penis and bifurcate accessory piece. Diagnostically, D. olfactorius n. sp. has relatively small anchors, hooks of anchor length, and a thin, long dorsal bar and no apparent ventral bar nor 4A hooks. Scanning electron microscopy revealed the body tegument of D. olfactorius n. sp. to be microvillous and in shallow annular folds, while that of D. bifurcatus, occurring on host gills of the same fish, was avillous and in gill-like folds dorsally and ventrally. Partial 28S rDNA sequences revealed significant differences between the two species, supporting establishment of D. olfactorius n. sp. and dispelling the possibility of ecophenotypic effects of site of attachment on morphology. PMID:27307170

  4. Predicting Fecundity of Fathead Minnows (Pimephales promelas) Exposed to Endocrine-Disrupting Chemicals Using a MATLAB®-Based Model of Oocyte Growth Dynamics.

    PubMed

    Watanabe, Karen H; Mayo, Michael; Jensen, Kathleen M; Villeneuve, Daniel L; Ankley, Gerald T; Perkins, Edward J

    2016-01-01

    Fish spawning is often used as an integrated measure of reproductive toxicity, and an indicator of aquatic ecosystem health in the context of forecasting potential population-level effects considered important for ecological risk assessment. Consequently, there is a need for flexible, widely-applicable, biologically-based models that can predict changes in fecundity in response to chemical exposures, based on readily measured biochemical endpoints, such as plasma vitellogenin (VTG) concentrations, as input parameters. Herein we describe a MATLAB® version of an oocyte growth dynamics model for fathead minnows (Pimephales promelas) with a graphical user interface based upon a previously published model developed with MCSim software and evaluated with data from fathead minnows exposed to an androgenic chemical, 17β-trenbolone. We extended the evaluation of our new model to include six chemicals that inhibit enzymes involved in steroid biosynthesis: fadrozole, ketoconazole, propiconazole, prochloraz, fenarimol, and trilostane. In addition, for unexposed fathead minnows from group spawning design studies, and those exposed to the six chemicals, we evaluated whether the model is capable of predicting the average number of eggs per spawn and the average number of spawns per female, which was not evaluated previously. The new model is significantly improved in terms of ease of use, platform independence, and utility for providing output in a format that can be used as input into a population dynamics model. Model-predicted minimum and maximum cumulative fecundity over time encompassed the observed data for fadrozole and most propiconazole, prochloraz, fenarimol and trilostane treatments, but did not consistently replicate results from ketoconazole treatments. For average fecundity (eggs•female(-1)•day(-1)), eggs per spawn, and the number of spawns per female, the range of model-predicted values generally encompassed the experimentally observed values. Overall, we

  5. Predicting Fecundity of Fathead Minnows (Pimephales promelas) Exposed to Endocrine-Disrupting Chemicals Using a MATLAB®-Based Model of Oocyte Growth Dynamics.

    PubMed

    Watanabe, Karen H; Mayo, Michael; Jensen, Kathleen M; Villeneuve, Daniel L; Ankley, Gerald T; Perkins, Edward J

    2016-01-01

    Fish spawning is often used as an integrated measure of reproductive toxicity, and an indicator of aquatic ecosystem health in the context of forecasting potential population-level effects considered important for ecological risk assessment. Consequently, there is a need for flexible, widely-applicable, biologically-based models that can predict changes in fecundity in response to chemical exposures, based on readily measured biochemical endpoints, such as plasma vitellogenin (VTG) concentrations, as input parameters. Herein we describe a MATLAB® version of an oocyte growth dynamics model for fathead minnows (Pimephales promelas) with a graphical user interface based upon a previously published model developed with MCSim software and evaluated with data from fathead minnows exposed to an androgenic chemical, 17β-trenbolone. We extended the evaluation of our new model to include six chemicals that inhibit enzymes involved in steroid biosynthesis: fadrozole, ketoconazole, propiconazole, prochloraz, fenarimol, and trilostane. In addition, for unexposed fathead minnows from group spawning design studies, and those exposed to the six chemicals, we evaluated whether the model is capable of predicting the average number of eggs per spawn and the average number of spawns per female, which was not evaluated previously. The new model is significantly improved in terms of ease of use, platform independence, and utility for providing output in a format that can be used as input into a population dynamics model. Model-predicted minimum and maximum cumulative fecundity over time encompassed the observed data for fadrozole and most propiconazole, prochloraz, fenarimol and trilostane treatments, but did not consistently replicate results from ketoconazole treatments. For average fecundity (eggs•female(-1)•day(-1)), eggs per spawn, and the number of spawns per female, the range of model-predicted values generally encompassed the experimentally observed values. Overall, we

  6. Predicting Fecundity of Fathead Minnows (Pimephales promelas) Exposed to Endocrine-Disrupting Chemicals Using a MATLAB®-Based Model of Oocyte Growth Dynamics

    PubMed Central

    Watanabe, Karen H.; Mayo, Michael

    2016-01-01

    Fish spawning is often used as an integrated measure of reproductive toxicity, and an indicator of aquatic ecosystem health in the context of forecasting potential population-level effects considered important for ecological risk assessment. Consequently, there is a need for flexible, widely-applicable, biologically-based models that can predict changes in fecundity in response to chemical exposures, based on readily measured biochemical endpoints, such as plasma vitellogenin (VTG) concentrations, as input parameters. Herein we describe a MATLAB® version of an oocyte growth dynamics model for fathead minnows (Pimephales promelas) with a graphical user interface based upon a previously published model developed with MCSim software and evaluated with data from fathead minnows exposed to an androgenic chemical, 17β-trenbolone. We extended the evaluation of our new model to include six chemicals that inhibit enzymes involved in steroid biosynthesis: fadrozole, ketoconazole, propiconazole, prochloraz, fenarimol, and trilostane. In addition, for unexposed fathead minnows from group spawning design studies, and those exposed to the six chemicals, we evaluated whether the model is capable of predicting the average number of eggs per spawn and the average number of spawns per female, which was not evaluated previously. The new model is significantly improved in terms of ease of use, platform independence, and utility for providing output in a format that can be used as input into a population dynamics model. Model-predicted minimum and maximum cumulative fecundity over time encompassed the observed data for fadrozole and most propiconazole, prochloraz, fenarimol and trilostane treatments, but did not consistently replicate results from ketoconazole treatments. For average fecundity (eggs•female-1•day-1), eggs per spawn, and the number of spawns per female, the range of model-predicted values generally encompassed the experimentally observed values. Overall, we found

  7. Androgenic and estrogenic effects of the synthetic androgen 17alpha-methyltestosterone on sexual development and reproductive performance in the fathead minnow (Pimephales promelas) determined using the gonadal recrudescence assay.

    PubMed

    Pawlowski, S; Sauer, A; Shears, J A; Tyler, C R; Braunbeck, T

    2004-06-24

    The effects of the androgen, 17alpha-methyltestosterone were assessed on sexual development and reproductive performance in the fathead minnow (Pimephales promelas) using a gonadal recrudescence assay. In this assay, mature male and female fathead minnow, previously kept under simulated winter conditions (15 degrees C; 8:16 h light:dark regime) were transferred to simulated summer conditions (25 degrees C water temperature; 16:8 h light:dark regime) to induce gonadal recrudescence. To assess sexual development fish were exposed to nominal concentrations of 0, 0.1, 1, 5 and 50 microg/L 17alpha-methyltestosterone. After 3 weeks of chemical exposure, effects on condition (condition factor, CF), plasma vitellogenin (VTG), secondary sex characteristics, gonad growth (gonadosomatic index; GSI) and gonad histology were investigated. Reproductive performance, including reproductive output (egg production), spawning behaviour, and fertilisation rate were measured over a subsequent 3-week-period in breeding adults maintained in clean water. 17alpha-Methyltestosterone had no effects on the condition of fish at any of the doses tested. 17alpha-Methyltestosterone induced both androgenic and estrogenic effects with females generally more affected by 17alpha-methyltestosterone than males: atretic follicles and male-specific sex characteristics (androgenic effect) were induced in females at > or = 0.1 and > or = 1 microg/L 17alpha-methyltestosterone, respectively. An inhibitory effect on ovary growth occurred at an exposure concentration of 50 microg/L 17alpha-methyltestosterone. In males 1 microg/L 17alpha-methyltestosterone induced a concentration-response induction of plasma vitellogenin (estrogenic effect) likely due to its conversion into 17alpha-methylestradiol, rather to the competition with endogenous steroids and their cross reactivity with the estrogen receptor. In the fish breeding studies, concentration-dependent reductions in egg number, fertilisation rate and

  8. Prediction of the acute toxicity (96-h LC50) of organic compounds to the fathead minnow (Pimephales promelas) using a group contribution method.

    PubMed

    Martin, T M; Young, D M

    2001-10-01

    A group contribution method has been developed to correlate the acute toxicity (96-h LC50) to the fathead minnow (Pimephales promelas) for 397 organic chemicals. Multilinear regression and computational neural networks (CNNs) were used for model building. The models were able to achieve a fairly good correlation of the data (r2 > 0.9). The linear model, which included four specific interaction terms, provided a rapid means of predicting the toxicity of a compound. The CNN model was able to yield virtually the same predictions with or without the four interaction terms that were included in the multilinear model.

  9. Effects of acute and chronic waterborne lead exposure on the swimming performance and aerobic scope of fathead minnows (Pimephales promelas).

    PubMed

    Mager, Edward M; Grosell, Martin

    2011-06-01

    Fathead minnows were subjected to an incremental velocity test using swim tunnel respirometry for the analysis of aerobic scope and swimming performance, as critical aerobic swim speed (U(crit)), following chronic exposures (33-57 ) to 0.9±0.4, 157±18 or 689±66 nmol L⁻¹ Pb and an acute exposure (24 h) to 672±35 nmol L⁻¹ Pb (mean±SEM). Assessment of Pb-induced anemia and neurological impairment were evaluated by blood hemoglobin (Hb) concentrations and a cost of transport (COT) analysis, respectively. Fish from the acute 672±35 nmol L⁻¹ Pb (24.4±1.2 BL s⁻¹) and chronic 689±66 nmol L⁻¹ Pb (24.6±0.9 BL s⁻¹) treatments exhibited reduced U(crits) compared to control fish (27.6±0.8 BL s⁻¹). Aerobic scope was reduced by acute Pb exposure (8.6±2.6 μmol O₂ g⁻¹ h⁻¹ vs. 22.6±3.8 μmol O₂ g⁻¹ h⁻¹ from controls) owing to a decrease in maximum oxygen consumption rate (38.8±0.8 μmol O₂ g⁻¹ h⁻¹ vs. 54.0±4.2 μmol O₂ g⁻¹ h⁻¹ from controls). However, no effect on aerobic scope was observed with fish chronically exposed to Pb. Significant differences were not observed for Hb concentrations or COT. These findings suggest that the impaired swimming performances arising from acute and chronic Pb exposures reflect different mechanisms of toxicity.

  10. Evaluation of potential mechanisms of atrazine-induced reproductive impairment in fathead minnow (Pimephales promelas) and Japanese medaka (Oryzias latipes).

    PubMed

    Richter, Catherine A; Papoulias, Diana M; Whyte, Jeffrey J; Tillitt, Donald E

    2016-09-01

    Atrazine has been implicated in reproductive dysfunction of exposed organisms, and previous studies documented decreased egg production in Japanese medaka (Oryzias latipes) and fathead minnows (Pimephales promelas) during 30-d to 38-d exposures to 0.5 µg/L, 5 µg/L, and 50 µg/L atrazine. The authors evaluated possible mechanisms underlying the reduction in egg production. Gene expression in steroidogenesis pathways and the hypothalamus-pituitary-gonad axis of male and female fish was measured. Atrazine did not significantly induce gonad aromatase (cyp19a1a) expression. An atrazine-induced shift in the number of females in an active reproductive state was observed. Expression of the egg maturation genes vitellogenin 1 (vtg1) and zona pellucida glycoprotein 3.1 (zp3.1) in medaka females was correlated and had a bimodal distribution. In both species, females with low vtg1 or zp3.1 expression also had low expression of steroidogenesis genes in the gonad, estrogen receptor in the liver, and gonadotropins in the brain. In the medaka, the number of females per tank that had high expression of zp3.1 was significantly correlated with egg production per tank. The number of medaka females with low expression of zp3.1 increased significantly with atrazine exposure. Thus, the decline in egg production observed in response to atrazine exposure may be the result of a coordinated downregulation of genes required for reproduction in a subset of females. Environ Toxicol Chem 2016;35:2230-2238. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America. PMID:26792394

  11. Individual and combined effects of heat stress and aqueous or dietary copper exposure in fathead minnows (Pimephales promelas).

    PubMed

    Lapointe, Dominique; Pierron, Fabien; Couture, Patrice

    2011-07-01

    Despite its role as an essential micronutrient, copper (Cu) can be present in aquatic ecosystems at concentrations able to cause adverse health effects on aquatic organisms. Although Cu is acquired by fish by either water or diet, studies that have investigated Cu impacts in fish have mainly focused on the toxicity of waterborne Cu. Moreover, as the majority of experiments were carried out under simplified conditions, little is known about the effects of natural factors other than competitive ions on Cu toxicity in fish. As temperature is a primary factor that affects the physiological state of poikilotherm organisms, we investigated the individual and combined effects of temperature and waterborne or dietary Cu on fathead minnows (Pimephales promelas). Fish were exposed to environmentally realistic concentrations of waterborne or dietary Cu at 20 °C and 32 °C. Transcriptional and enzymatic responses of various indicators of metabolic capacities as well as indicators of heat, oxidative and metal stresses were measured in fish muscle. Under our experimental conditions, temperature was the most important factor affecting the general condition of fish. Although no significant Cu accumulation was observed in the muscle of Cu-exposed fish, at 20 °C, waterborne and dietary Cu triggered significant changes in the transcription level of genes encoding for proteins involved in energy metabolism, metal detoxification and protein protection. Moreover, the response was quantitatively more important for dietary Cu than for waterborne Cu. Combined exposure to heat and Cu triggered the most significant changes in gene transcription levels and enzyme activities. During combined exposure to heat and Cu, in addition to synergistic effects of the two factors, both waterborne and dietary Cu impaired the adaptive response developed by fish to curb heat stress. Reciprocally, temperature impaired the adaptive response developed by fish to combat Cu toxicity. These results suggest that

  12. Transcripts involved in steroid biosynthesis and steroid receptor signaling are expressed early in development in the fathead minnow (Pimephales promelas).

    PubMed

    Wood, Richard K; Seidel, Jason S; Martyniuk, Christopher J

    2015-04-01

    Sex differentiation in organisms is correlated to sex steroid production and receptor signaling pathways involving androgens and estrogens. Timing of expression is critical, and characterization of sensitive windows is needed to determine how environmental stressors may perturb sex differentiation. The objectives of this study were to determine whether genes related to steroid biosynthesis, steroid receptor signaling, and those related to sex differentiation were expressed in pre-differentiated fathead minnow (FHM) embryos, an ecotoxicological model. Transcripts were measured over two weeks (1 day post fertilization (dpf) to 14 days), prior to sex differentiation. The first three time points investigated (1, 3, and 5 dpf) corresponded to the neurula stage, dorsal swim bladder pigmentation, and pre-hatch. The fourth time point (6 dpf) was collected immediately post-hatch and the fifth time point investigated was after 8 days of larval growth (14 dpf). The majority of transcripts investigated, for example estrogen, androgen, and thyroid receptors as well as steroid biosynthesis transcripts, were expressed within the first 72 hours of development; exceptions were star (steroidogenic acute regulatory protein) and cyp19a, which did not have detectable expression until 5 dpf (pre-hatch). Transcripts that increased in relative mRNA abundance over the first two weeks of development included ar, dax1, hsd11b2, hsd17b, cyp19a and thra. This study demonstrates that there is early expression of transcripts related to steroid biosynthesis, steroid receptor signaling, and sex differentiation in pre-hatch FHM embryos. Additional studies are required to determine their relative roles in male and female differentiation during these early developmental periods.

  13. Detecting population-level genotoxic effects of benzo(a)pyrene on the fathead minnow (Pimephales promelas)

    SciTech Connect

    White, P.A.; Rasmussen, J.B.

    1995-12-31

    Investigations of benzo(a)pyrene (BaP) toxicity have been primarily concerned with effects mediated by somatic cell DNA damage, particularly those linked to carcinogenesis. However, somatic cell effects may be of little ecological consequence, particularly when resulting pathologies become clinically visible long after sexual maturity. Germ cell effects may be more consequential, with alterations of the germ cell mutation rate effecting the dynamics of entire populations. The goal was to demonstrate that a potent DNA damaging agent can induce detectable population level effects. To accomplish this task the authors investigated changes in the survivorship of fathead minnow larvae two generations removed from in vitro BaP exposure. The experiment was initiated by exposing laboratory-raised individuals to 0.1, 0.5, 1.0 ppb BaP or a solvent blank for a period of 3 months. Exposed pairs were isolated and mated as soon as secondary sexual characteristics became visible. Progeny of exposed, mated pairs were subsequently isolated in order to provide families with a known exposure history. Siblings from isolated families were then mated to examine the effect of BaP exposure on the survival of larvae two generations removed from the exposure. As expected, inbreeding depression decreased hatching success and larval survival in both control and experimental broods. However, while larval survival from control broods was usually greater than 50%, two-thirds of the 1 ppb BaP broods showed no survival at all. Overall, the results revealed a significant effect of BaP treatment on both hatching success and larval survival. The results also revealed evidence of a concentration-response relationship.

  14. Comparative acute toxicity of a synthetic mine effluent to Ceriodaphnia dubia, larval fathead minnow and the freshwater mussel Anodonta imbecilis

    SciTech Connect

    Masnado, R.G.; Geis, S.W.; Sonzogni, W.C.

    1995-11-01

    To determine if water quality-based effluent limitations recommended for a proposed discharger would provide adequate protection of aquatic life, site-specific acute toxicity tests were performed. The proposed discharger studied was a mine to be located in northern Wisconsin. The mine`s discharge would flow into the Flambeau River, a relatively pristine river that harbors endangered freshwater mussels. The toxicity effects of synthetic effluents, representing a mixture of five different metals under contrasting conditions of hardness, were tested on several different organisms. Results indicated that Ceriodaphnia dubia exhibited a much greater sensitivity to various mixtures of cadmium, hexavalent chromium, copper, nickel, and zinc than did either larval fathead minnows (Pimephales promelas) or the freshwater mussel Anodonta imbecilis. Mixture o metals at the permitted discharge levels of individual metals were also found to be consistently toxic to C. dubia. Because C. dubia was found to be much more sensitive than A. imbecilis, an effluent safe for C. dubia should also be safe for A. imbecilis and the physiologically similar endangered mussels found in the river. Based on such testing, aquatic life toxicity-testing conditions and criteria suggested for the National Pollution Discharge Elimination System (NPDES) permit should be protective of C. dubia and, hence, other aquatic life such as endangered mussels. Overall, effluent limitations for proposed dischargers need to be based on the combined effect of complex effluents. Aquatic toxicity testing using synthetic effluents that approximate the expected discharge characteristics provides a viable approach to determining the limits for proposed dischargers of multiple pollutants.

  15. Dietary Exposure of Fathead Minnows to the Explosives TNT and RDX and to the Pesticide DDT using Contaminated Invertebrates

    PubMed Central

    Houston, Jerre G.; Lotufo, Guilherme R.

    2005-01-01

    Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT), a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas). Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms) was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario. PMID:16705829

  16. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on early life stage development of the fathead minnow (Pimephales promelas)

    SciTech Connect

    Winden, P.J.J. de; Donselaar, E.G. van; Herwig, H.J.

    1994-12-31

    Eggs of fathead minnow were exposed to graded concentrations (0.1--100 ppt) of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at 24 C for 5 days. Exposure started about one hour after fertilization. The medium was refreshed daily. At day 6 (one day posthatching), body lengths were measured. A dose-dependent retardation of growth (from 1 to 30%) was observed in the range from 0.1 to 20 ppt TCDD. At higher concentrations, growth reduction remained the same but mortality still increased. Microscopic observations of the TCDD-exposed embryos revealed a number of deviations from the normal early development. Initial changes consisted of congestion of the blood flow in the caudal tail area and in the yolk sac vascular complex, followed by hemorrhages. At a later stage, pericardial edema and generalized edema were observed. In addition the embryos revealed, anaemia, decreased amounts of dermal and retinal melanin, shortened mandibles, degeneration of heart tissue, absence of swim bladder, decreased utilization of yolk sac material and a curved chords. The results indicate that embryonic development of the fathead minnow is very sensitive to TCDD. It might prove a useful model for further embryotoxic studies.

  17. Pathway-based approaches for assessment of real-time exposure to an estrogenic wastewater treatment plant effluent on fathead minnow reproduction

    USGS Publications Warehouse

    Cavallin, Jenna E.; Jensen, Kathleen M.; Kahl, Michael D.; Villeneuve, Daniel L.; Lee, Kathy E.; Schroeder, Anthony L.; Mayasich, Joe; Eid, Evan P.; Nelson, Krysta R.; Milsk, Rebecca Y.; Blackwell, Brett R.; Berninger, Jason P.; LaLone, Carlie A.; Blanskma, Chad; Jicha, Terri M.; Elonen, Colleen M.; Johnson, Rodney C.; Ankley, Gerald T.

    2016-01-01

    Wastewater treatment plant (WWTP) effluents are known contributors of chemical mixtures into the environment. Of particular concern are endocrine-disrupting compounds, such as estrogens, which can affect the hypothalamic-pituitary-gonadal axis function in exposed organisms. The present study examined reproductive effects in fathead minnows exposed for 21 d to a historically estrogenic WWTP effluent. Fathead minnow breeding pairs were held in control water or 1 of 3 effluent concentrations (5%, 20%, and 100%) in a novel onsite, flow-through system providing real-time exposure. The authors examined molecular and biochemical endpoints representing key events along adverse outcome pathways linking estrogen receptor activation and other molecular initiating events to reproductive impairment. In addition, the authors used chemical analysis of the effluent to construct a chemical-gene interaction network to aid in targeted gene expression analyses and identifying potentially impacted biological pathways. Cumulative fecundity was significantly reduced in fish exposed to 100% effluent but increased in those exposed to 20% effluent, the approximate dilution factor in the receiving waters. Plasma vitellogenin concentrations in males increased in a dose-dependent manner with effluent concentration; however, male fertility was not impacted. Although in vitro analyses, analytical chemistry, and biomarker responses confirmed the effluent was estrogenic, estrogen receptor agonists were unlikely the primary driver of impaired reproduction. The results provide insights into the significance of pathway-based effects with regard to predicting adverse reproductive outcomes.

  18. Computational model of the fathead minnow hypothalamic-pituitary-gonadal axis: Incorporating protein synthesis in improving predictability of responses to endocrine active chemicals.

    PubMed

    Breen, Miyuki; Villeneuve, Daniel L; Ankley, Gerald T; Bencic, David; Breen, Michael S; Watanabe, Karen H; Lloyd, Alun L; Conolly, Rory B

    2016-01-01

    There is international concern about chemicals that alter endocrine system function in humans and/or wildlife and subsequently cause adverse effects. We previously developed a mechanistic computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows exposed to a model aromatase inhibitor, fadrozole (FAD), to predict dose-response and time-course behaviors for apical reproductive endpoints. Initial efforts to develop a computational model describing adaptive responses to endocrine stress providing good fits to empirical plasma 17β-estradiol (E2) data in exposed fish were only partially successful, which suggests that additional regulatory biology processes need to be considered. In this study, we addressed short-comings of the previous model by incorporating additional details concerning CYP19A (aromatase) protein synthesis. Predictions based on the revised model were evaluated using plasma E2 concentrations and ovarian cytochrome P450 (CYP) 19A aromatase mRNA data from two fathead minnow time-course experiments with FAD, as well as from a third 4-day study. The extended model provides better fits to measured E2 time-course concentrations, and the model accurately predicts CYP19A mRNA fold changes and plasma E2 dose-response from the 4-d concentration-response study. This study suggests that aromatase protein synthesis is an important process in the biological system to model the effects of FAD exposure.

  19. Determining the effects of a mixture of an endocrine disrupting compound, 17α-ethinylestradiol, and ammonia on fathead minnow (Pimephales promelas) reproduction.

    PubMed

    Armstrong, Brandon M; Lazorchak, James M; Murphy, Cheryl A; Haring, Herman J; Jensen, Kathleen M; Smith, Mark E

    2015-02-01

    Aquatic organisms are exposed to a multitude of contaminants and to fully understand the impact of multiple stressors on fish populations, we must first understand the mechanism of action for each toxicant and how the combined effects manifest at the level of the individual. 17α-ethinylestradiol (EE2) has been known to cause adverse reproductive effects including reduced fecundity and fertility, intersex and skewed sex ratios in fish by mimicking naturally produced estrogen at low concentrations. Ammonia can cause adverse reproductive and mortality effects in individual fish through effects or damage to the central nervous system. Both EE2 and ammonia are found in most municipal effluents in various concentrations. A flow-through diluter system was used to test the individual effects of these two contaminants at their respective no observable adverse effect concentration (NOAEC) as well as their combined effects on fathead minnow, (Pimephales promelas) reproduction in a mixture exposure. While neither contaminant nor their mixture altered reproduction in terms of fecundity, their mixture resulted in significant fathead minnow mortality during a 21 d exposure. This study demonstrated the need to consider mixture effects when assessing risk for toxicity testing with multiple stressors. PMID:25014901

  20. Expression of two vitellogenin genes (vg1 and vg3) in fathead minnow (Pimephales promelas) liver in response to exposure to steroidal estrogens and androgens.

    SciTech Connect

    Miracle, Ann L.; Ankley, Gerald; Lattier, David

    2006-03-01

    In this study, we describe the sequence for the fathead minnow (Pimephales promelas) vitellogenin 3 gene (vg3), and compare the response of vg1 and vg3 following exposure to steroidal estrogens and androgens. The fathead minnow vg3 sequence is only the second nucleotide sequence described in teleosts, following the original description of this isoform in zebrafish (Danio rerio). Following a brief exposure (24 hours) to 2, 5, and 10 ng/L 17 alpha-ethynylestradiol (EE2), both vg1and vg3 are upregulated in male liver. However, levels of vg3 induction are 4 orders of magnitude lower than induction of vg1. Suppression of vg in female liver following androgenic exposure with 50 or 500 ng/L 17 beta-trenbolone occurs at similar significance levels for both vg1 and vg3 isoforms. The results of this study confirm the use of vg1 as an indicator of estrogenic exposure in male fish, and present the potential for vg1 and /or vg3 for use as indicators of androgenic exposure.

  1. Comparison of short-term chronic and chronic silver toxicity to fathead minnows in unamended and sodium chloride-amended waters.

    PubMed

    Naddy, Rami B; Rehner, Anita B; McNerney, Gina R; Gorsuch, Joseph W; Kramer, James R; Wood, Chris M; Paquin, Paul R; Stubblefield, William A

    2007-09-01

    The chronic (early life stage [ELS]) and short-term chronic (STC) toxicity of silver (as silver nitrate) to fathead minnows (FHM) was determined concurrently in flow-through exposures (33 volume additions/d). Paired ELS (approximately 30 d) and STC (7 d) studies were conducted with and without the addition of 60 mg/L Cl (as NaCl). The paired studies in unamended water were later repeated using standard flow conditions (9 volume additions/d). The purpose of the paired studies was to determine if short-term chronic endpoints can be used to predict effects in ELS studies. For each experiment, a "split-chamber" design (organisms were held in a common exposure chamber) allowed the direct comparison between short-term and chronic exposures. It appeared that the chronic toxicity of silver was mitigated to some extent by NaCl addition. The maximum acceptable toxicant concentration for growth in the ELS study was 0.53 microg dissolved Ag/L under standard flow conditions. Early life stage and STC endpoints in all three studies typically agreed within a factor of two. Whole-body sodium and silver concentrations measured in individual fathead minnows during these studies showed an increase in silver body burdens and a decrease in sodium concentration. These results indicate that the STC study could be used as a surrogate test to estimate chronic toxicity and that the mechanism of chronic silver toxicity may be the same as for acute toxicity.

  2. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    SciTech Connect

    Simbeck, D.J.

    1994-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of January 25--February 1, 1994. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected from Clinch River Mile 9.0, Poplar Creek Mile 1.0, and Poplar Creek Mile 2.9 on January 24, 26, and 28. Samples were partitioned and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to fathead minnows; however, toxicity to daphnids was demonstrated in undiluted samples from Poplar Creek Mile 1.0 in testing conducted by TVA based on hypothesis testing of data. Point estimation (IC{sub 25}) analysis of the data, however, showed no toxicity in PCM 1.0 samples. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Meter calibrations; and Reference toxicant test information.

  3. Pathway-based approaches for assessment of real-time exposure to an estrogenic wastewater treatment plant effluent on fathead minnow reproduction.

    PubMed

    Cavallin, Jenna E; Jensen, Kathleen M; Kahl, Michael D; Villeneuve, Daniel L; Lee, Kathy E; Schroeder, Anthony L; Mayasich, Joe; Eid, Evan P; Nelson, Krysta R; Milsk, Rebecca Y; Blackwell, Brett R; Berninger, Jason P; LaLone, Carlie A; Blanksma, Chad; Jicha, Terri; Elonen, Colleen; Johnson, Rodney; Ankley, Gerald T

    2016-03-01

    Wastewater treatment plant (WWTP) effluents are known contributors of chemical mixtures into the environment. Of particular concern are endocrine-disrupting compounds, such as estrogens, which can affect the hypothalamic-pituitary-gonadal axis function in exposed organisms. The present study examined reproductive effects in fathead minnows exposed for 21 d to a historically estrogenic WWTP effluent. Fathead minnow breeding pairs were held in control water or 1 of 3 effluent concentrations (5%, 20%, and 100%) in a novel onsite, flow-through system providing real-time exposure. The authors examined molecular and biochemical endpoints representing key events along adverse outcome pathways linking estrogen receptor activation and other molecular initiating events to reproductive impairment. In addition, the authors used chemical analysis of the effluent to construct a chemical-gene interaction network to aid in targeted gene expression analyses and identifying potentially impacted biological pathways. Cumulative fecundity was significantly reduced in fish exposed to 100% effluent but increased in those exposed to 20% effluent, the approximate dilution factor in the receiving waters. Plasma vitellogenin concentrations in males increased in a dose-dependent manner with effluent concentration; however, male fertility was not impacted. Although in vitro analyses, analytical chemistry, and biomarker responses confirmed the effluent was estrogenic, estrogen receptor agonists were unlikely the primary driver of impaired reproduction. The results provide insights into the significance of pathway-based effects with regard to predicting adverse reproductive outcomes.

  4. Method for Detection and Quantitation of Fathead Minnow Vitellogenin (Vtg) by Liquid Chromatography and Matrix Assisted Laser Desorption/ Ionization Mass Spectrometry

    SciTech Connect

    Wunschel, David S.; Schultz, Irv R.; Skillman, Ann D.; Wahl, Karen L.

    2005-03-11

    Vitellogenin (Vtg) is a well recognized biomarker of estrogen exposure in many species, particularly fish. This large protein shares a high degree of sequence homology across a large number of species. Quantitative measurement is currently done using antibody-based assays. These assays frequently require purification of Vtg and antibody production from each species because there is poor cross reactivity between antibodies for different fish. Therefore, complementary methods of measuring Vtg are desirable. Mass spectrometric (MS) analysis coupled to database searching offers the promise of a general method for protein identification. In this study we used the well characterized Vtg from rainbow trout (O. mykiss) to evaluate the analytical parameters for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of the intact and tryptic digested protein. An analytical scale HPLC separation combined with MALDI-MS was used to measure and confirm the identity of Vtg from the plasma of an important species for regulatory agencies, fathead minnow (Pimephales promelas). The small volume requirement of this method (< 10 uL) was found to be compatible with the plasma volume obtained from a few minnows. A semi quantitative measurement of Vtg from minnows exposed to estradiol was achieved, which was similar to previously obtained ELISA data.

  5. Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to embryos of the fathead minnow (Pimephales promelas, Rafinesque)

    SciTech Connect

    Olivieri, C.; Cooper, K.

    1995-12-31

    This study correlates the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) residue and its toxicity to the fathead minnow embryo exposed to levels lower than the TCDD solubility range. The TCDD tissue doses in the embryo/larvae were related to gross lesions, delayed hatching, and death. A 7-day bioconcentration factor on a lipid basis (BCF{sub L}) was calculated. Embryos at the blatsula stage were exposed to [{sup 3}H] TCDD water concentrations (0.37, 0.59, 1.2, 2.83, and 10.1 6 ng/L), a nontreatment control and a solvent carrier control. Lesions were qualified as mild and severe based on their onset and their pathogenesis. Thus, mild lesions developed just prior to hatching or post-hatching at the fifth day of development. The severe lesions appeared at the third day of development. Embryos with tissue doses {le}2.46 {+-} 1.34 ng/g consistently developed mild lesions, while embryos with tissue doses {ge} 12.07 {+-} 4.91 ng/g developed severe lesions. The lowest observable adverse effect level was 0.04 {+-} 0.02 ng/g. The calculated 7-day ED{sub 50} was 0.14 ng/g. There was no delayed hatching at any of the concentrations tested. Embryo death occurred at a tissue concentration {ge}2.46 ng/g. The calculated 7-day LD{sub 50} was 25.71 ng/g. The relationship between the concentration of TCDD in the water (x = ng/L) and in the tissue dose (y = ng/g) fitted a linear curve y = {minus}1,143 + 3,792.5x, r{sup 2} = 0.98. The calculated BCF{sub L} (wet weight) was dose dependent. Embryos with tissue doses of 0.04 and 0.16 ng/g had BCF{sub L} of 2,700 and 3,325, respectively. Embryos with tissue doses of 2.46, 12.07, and 37.07 ng/g, had a BCF{sub L} of 104,225, 106,625 and 91,075, respectively.

  6. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    SciTech Connect

    Russell, C.L.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22--29, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  7. Short and long term bystander effect induction by fathead minnows (Pimephales promelas, Rafinesque, 1820) injected with environmentally relevant whole body doses of 226Ra.

    PubMed

    Smith, Richard W; Seymour, Colin B; Mothersill, Carmel E

    2013-12-01

    Bystander effect induction by fathead minnows injected with environmentally relevant doses of (226)Ra was investigated. Twenty four h and 6 months after injection with a single dose of 21, 210 or 2100 μBq, fin tissue samples emitted a pro-apoptotic signal, which reduced the clonogenic survival of an apoptosis sensitive reporter cell line. Twenty four h and 10 weeks after injection explants from non-injected bystander fish, swum with the injected fish, also emitted a pro-apoptotic signal. However 6 months after injection the bystander fish to 21 and 210 μBq injected fish emitted an anti-apoptotic signal. This demonstrates that extremely low dose irradiation can have effects outside of the irradiated fish. This has implications for population and ecosystem responses to contamination. PMID:23981564

  8. Effects of Sediment Containing Coal Ash from the Kingston Ash Release on Embryo-Larval Development in the Fathead Minnow, Pimephales promelas (Rafinesque, 1820)

    SciTech Connect

    Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty; Sherrard, Rick

    2014-01-01

    The largest environmental release of coal ash in U.S. history occurred in December 2008 with the failure of a retention structure at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in East Tennessee. A byproduct of coal-burning power plants, coal ash is enriched in metals and metalloids such as selenium and arsenic with known toxicity to fish including embryonic and larval stages. The effects of contact exposure to sediments containing up to 78 % coal ash from the Kingston spill on the early development of fish embryos and larvae were examined in 7-day laboratory tests with the fathead minnow (Pimephales promelas). No significant effects were observed on hatching success, incidences of gross developmental abnormalities, or embryo-larval survival. Results suggest that direct exposures to sediment containing residual coal ash from the Kingston ash release may not present significant risks to fish eggs and larvae in waterways affected by the spill.

  9. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

    SciTech Connect

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22--29, 1993, prior to initiation of CR-ERP Phase 2 Sampling and Analysis activities. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Reference toxicant test information; and Personnel training documentation.

  10. Site-specific impacts on gene expression and behavior in fathead minnows (Pimephales promelas) exposed in situ to streams adjacent to sewage treatment plants

    PubMed Central

    2009-01-01

    Background Environmental monitoring for pharmaceuticals and endocrine disruptors in the aquatic environment traditionally employs a variety of methods including analytical chemistry, as well as a variety of histological and biochemical endpoints that correlate with the fish fitness. It is now clear that analytical chemistry alone is insufficient to identify aquatic environments that are compromised because these measurements do not identify the biologically available dose. The biological endpoints that are measured are important because they relate to known impairments; however, they are not specific to the contaminants and often focus on only a few known endpoints. These studies can be enhanced by looking more broadly at changes in gene expression, especially if the analysis focuses on biochemical pathways. The present study was designed to obtain additional information for well-characterized sites adjacent to sewage treatment plants in MN that are thought to be impacted by endocrine disruptors. Results Here we examine five sites that have been previously characterized and examine changes in gene expression in fathead minnows (Pimephales promelas) that have been caged for 48 h in each of the aquatic environments. We find that the gene expression changes are characteristic and unique at each of the five sites. Also, fish exposed to two of the sites, 7 and 12, present a more aggressive behavior compared to control fish. Conclusion Our results show that a short-term exposure to sewage treatment plant effluents was able to induce a site-specific gene expression pattern in the fathead minnow gonad and liver. The short-term exposure was also enough to affect fish sexual behavior. Our results also show that microarray analysis can be very useful at determining potential exposure to chemicals, and could be used routinely as a tool for environmental monitoring. PMID:19811676

  11. The fish embryo toxicity test as a replacement for the larval growth and survival test: A comparison of test sensitivity and identification of alternative endpoints in zebrafish and fathead minnows.

    PubMed

    Jeffries, Marlo K Sellin; Stultz, Amy E; Smith, Austin W; Stephens, Dane A; Rawlings, Jane M; Belanger, Scott E; Oris, James T

    2015-06-01

    The fish embryo toxicity (FET) test has been proposed as an alternative to the larval growth and survival (LGS) test. The objectives of the present study were to evaluate the sensitivity of the FET and LGS tests in fathead minnows (Pimephales promelas) and zebrafish (Danio rerio) and to determine if the inclusion of sublethal metrics as test endpoints could enhance test utility. In both species, LGS and FET tests were conducted using 2 simulated effluents. A comparison of median lethal concentrations determined via each test revealed significant differences between test types; however, it could not be determined which test was the least and/or most sensitive. At the conclusion of each test, developmental abnormalities and the expression of genes related to growth and toxicity were evaluated. Fathead minnows and zebrafish exposed to mock municipal wastewater-treatment plant effluent in a FET test experienced an increased incidence of pericardial edema and significant alterations in the expression of genes including insulin-like growth factors 1 and 2, heat shock protein 70, and cytochrome P4501A, suggesting that the inclusion of these endpoints could enhance test utility. The results not only show the utility of the fathead minnow FET test as a replacement for the LGS test but also provide evidence that inclusion of additional endpoints could improve the predictive power of the FET test.

  12. Application of endocrine disruptor screening program fish short-term reproduction assay: Reproduction and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus) exposed to Bermuda pond sediment.

    PubMed

    Fort, Douglas J; Mathis, Michael; Fort, Chelsea E; Fort, Hayley M; Bacon, Jamie P

    2015-06-01

    A modified tier 1 Endocrine Disruptor Screening Program (EDSP) 21-d fish short-term reproduction assay (FSTRA) was used to evaluate the effects of sediment exposure from freshwater and brackish ponds in Bermuda on reproductive fecundity and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus). Reproductively active male and female fish were exposed to control sediment and sediment from 2 freshwater ponds (fathead minnow) and 2 marine ponds (killifish) contaminated with polyaromatic hydrocarbons and metals via flow-through exposure for 21 d. Reproductive fecundity was monitored daily. At termination, the status of the reproductive endocrine system was assessed by the gonadosomatic index, gonadal histology, plasma steroids (estrogen [E2], testosterone [T], and 11-ketotestosterone [11-KT]), steroidogenic enzymes (aromatase and combined 3β/17β -hydroxysteroid dehydrogenase [3β/17β-HSD]), and plasma vitellogenin (VTG). Decreased reproductive fecundity, lower male body weight, and altered endocrinological measures of reproductive status were observed in both species. Higher plasma T levels in female minnows and 11-KT levels in both male and female minnows and female killifish exposed to freshwater and brackish sediments, respectively. Decreased female E2 and VTG levels and gonadal cytochrome P19 (aromatase) activity were also found in sediment exposed females from both species. No effect on female 3β/17β-HSD activity was found in either species. The FSTRA provided a robust model capable of modification to evaluate reproductive effects of sediment exposure in fish.

  13. A computational model of the hypothalamic-pituitary-gonadal axis in male fathead minnows exposed to 17alpha-ethinylestradiol and 17beta-estradiol.

    PubMed

    Watanabe, Karen H; Li, Zhenhong; Kroll, Kevin J; Villeneuve, Daniel L; Garcia-Reyero, Natàlia; Orlando, Edward F; Sepúlveda, Maria S; Collette, Timothy W; Ekman, Drew R; Ankley, Gerald T; Denslow, Nancy D

    2009-06-01

    Estrogenic chemicals in the aquatic environment have been shown to cause a variety of reproductive anomalies in fish including full sex reversal, intersex, and altered population sex ratios. Two estrogens found in the aquatic environment, 17alpha-ethinylestradiol (EE(2)) and 17beta-estradiol (E(2)), have been measured in wastewater treatment effluents and have been shown to cause adverse effects in fish. To further our understanding of how estrogen exposure affects reproductive endpoints in the male fathead minnow (FHM, Pimephales promelas), a physiologically based computational model was developed of the hypothalamic-pituitary-gonadal (HPG) axis. Apical reproductive endpoints in the model include plasma steroid hormone and vitellogenin concentrations. Using Markov chain Monte Carlo simulation, the model was calibrated with data from unexposed FHM, and FHM exposed to EE(2) and E(2). Independent experimental data sets were used to evaluate model predictions. We found good agreement between our model predictions and a variety of measured reproductive endpoints, although the model underpredicts unexposed FHM reproductive endpoint variances, and overpredicts variances in estrogen-exposed FHM. We conclude that this model provides a robust representation of the HPG axis in male FHM.

  14. Differential transcription of fathead minnow immune-related genes following infection with frog virus 3, an emerging pathogen of ectothermic vertebrates.

    PubMed

    Cheng, Kwang; Escalon, B Lynn; Robert, Jacques; Chinchar, V Gregory; Garcia-Reyero, Natàlia

    2014-05-01

    Frog virus 3 (FV3) and other ranaviruses are responsible for die-offs involving wild, farmed, and captive amphibians, fish, and reptiles. To ascertain which elements of the immune system respond to infection, we explored transcriptional responses following infection of fathead minnow cells with either wild type (wt) FV3 or a knock out (KO) mutant targeting the 18 kDa immediate early gene (18K). At 8h post infection we observed marked upregulation of multiple transcripts encoding proteins affecting innate and acquired immunity. Sequences expressed 4-fold or higher in wt-infected cells included transcripts encoding interferon (IFN), IFN regulatory factors (IRFs), IFN stimulated genes (ISGs) such as Mx and MHC class I, and interleukins IL-1β, IL-8, IL-17C and IL-12. Cells infected with the 18K KO mutant (∆18K) showed qualitative differences and lower levels of induction. Collectively, these results indicate that ranavirus infection induced expression of multiple cellular genes affecting both innate and acquired immunity.

  15. Exposure to the Contraceptive Progestin, Gestodene, Alters Reproductive Behavior, Arrests Egg Deposition, and Masculinizes Development in the Fathead Minnow (Pimephales promelas).

    PubMed

    Frankel, Tyler E; Meyer, Michael T; Kolpin, Dana W; Gillis, Amanda B; Alvarez, David A; Orlando, Edward F

    2016-06-01

    Endogenous progestogens and pharmaceutical progestins enter the environment through wastewater treatment plant effluent and agricultural field runoff. Lab studies demonstrate strong, negative exposure effects of these chemicals on aquatic vertebrate reproduction. Behavior can be a sensitive, early indicator of exposure to environmental contaminants associated with altered reproduction yet is rarely examined in ecotoxicology studies. Gestodene is a human contraceptive progestin and a potent activator of fish androgen receptors. Our objective was to test the effects of gestodene on reproductive behavior and associated egg deposition in the fathead minnow. After only 1 day, males exposed to ng/L of gestodene were more aggressive and less interested in courtship and mating, and exposed females displayed less female courtship behavior. Interestingly, 25% of the gestodene tanks contained a female that drove the male out of the breeding tile and displayed male-typical courtship behaviors toward the other female. Gestodene decreased or arrested egg deposition with no observed gonadal histopathology. Together, these results suggest that effects on egg deposition are primarily due to altered reproductive behavior. The mechanisms by which gestodene disrupts behavior are unknown. Nonetheless, the rapid and profound alterations of the reproductive biology of gestodene-exposed fish suggest that wild populations could be similarly affected. PMID:27129041

  16. Acclimation-induced changes in toxicity and induction of metallothionein-like proteins in the fathead minnow following sublethal exposure to cobalt, silver, and zinc

    SciTech Connect

    Hobson, J.F.

    1986-01-01

    Increases in tolerance and resistance to metal toxicity by aquatic organisms have been linked to elevated levels of low-molecular-weight metal-binding proteins (e.g., metallothioneins). Acclimation-induced changes in toxic response and the concentration of metallothionein-like proteins (MTP) were studied in laboratory populations of the fathead minnow, Pimephales promelas, following sublethal exposure to Co, Ag, and Zn. Following 7 and 14 days of sublethal exposure, tolerance and resistance, as measured by acute toxicity values, were altered in a dose dependent fashion. Acute toxicity values returned to control levels after 21 days of continuous exposure. Tolerance and resistance of Co- and Zn-acclimated animals were depressed after a 7-day post-acclimation period in control water. Tolerance and resistance of Ag-acclimated animals were temporarily enhanced after 7 days post-acclimation and returned to control levels after 14 days. Accumulation of Co, Ag, and Zn measured as wholebody residues appeared to be regulated in 4 of 6 exposure regimes with residues reaching stable levels after 7 to 14 days of exposure. MTP was induced by exposure to 1.8 mg Zn/L and 0.01 mg Ag/L, however, no sustained (i.e., post 21 days) tolerance or resistance were observed at these dose levels indicating that these two biological responses may not be directly related.

  17. Effect of Lipid Partitioning on Predictions of Acute Toxicity of Oil Sands Process Affected Water to Embryos of Fathead Minnow (Pimephales promelas).

    PubMed

    Morandi, Garrett D; Zhang, Kun; Wiseman, Steve B; Pereira, Alberto Dos Santos; Martin, Jonathan W; Giesy, John P

    2016-08-16

    Dissolved organic compounds in oil sands process affected water (OSPW) are known to be responsible for most of its toxicity to aquatic organisms, but the complexity of this mixture prevents use of traditional bottom-up approaches for predicting toxicities of mixtures. Therefore, a top-down approach to predict toxicity of the dissolved organic fraction of OSPW was developed and tested. Accurate masses (i.e., m/z) determined by ultrahigh resolution mass spectrometry in negative and positive ionization modes were used to assign empirical chemical formulas to each chemical species in the mixture. For each chemical species, a predictive measure of lipid accumulation was estimated by stir-bar sorptive extraction (SBSE) to poly(dimethyl)siloxane, or by partitioning to solid-supported lipid membranes (SSLM). A narcosis mode of action was assumed and the target-lipid model was used to estimate potencies of mixtures by assuming strict additivity. A model developed using a combination of the SBSE and SSLM lipid partitioning estimates, whereby the accumulation of chemicals to neutral and polar lipids was explicitly considered, was best for predicting empirical values of LC50 in 96-h acute toxicity tests with embryos of fathead minnow (Pimephales promelas). Model predictions were within 4-fold of observed toxicity for 75% of OSPW samples, and within 8.5-fold for all samples tested, which is comparable to the range of interlaboratory variability for in vivo toxicity testing. PMID:27420640

  18. Effects of waterborne exposure to 4-nonylphenol and nonylphenol ethoxylate on secondary sex characteristics and gonads of fathead minnows (Pimephales promelas)

    SciTech Connect

    Miles-Richardson, S.R.; Pierens, S.L.; Nichols, K.M.; Kramer, V.J.; Snyder, E.M.; Snyder, S.A.; Render, J.A.; Fitzgerald, S.D.; Giesy, J.P.

    1999-02-01

    Fathead minnows were exposed to 4-nonylphenol (NP) or nonylphenol ethoxylate (NPEO) to determine the effects of these weak estrogen agonists on secondary sex characteristics and gonads of sexually mature males and females during 42-day continuous-flow exposures. Neither NP nor NPEO caused statistically significant effects on tubercles or fatpad size at the concentrations tested. Exposure to 1.1 or 3.4 {micro}g NP.L caused changes in the number and size of Sertoli cells and germ cell syncytia. Necrotic aggregates of various stages of germ cells in the spermatogenic sequence were observed in the testes of males exposed to NP. Electron microscopy of the testes of NP-exposed males revealed the presence of phagocytic cells in the lumina of seminiferous tubules. The cytoplasm of some Sertoli cells was distended with myelin figures and necrotic spermatozoa. No significant effects on the stages of follicular development were observed in females exposed to NP. There were no differences in the gonads or secondary sex characteristics of males or females exposed to 5.5 {micro}g NPEO/L, the greatest concentration studied. The histologic responses observed are sensitive indicators of waterborne exposure to NP at environmentally relevant concentrations, but not as sensitive as induction of plasma vitellogenin.

  19. Chronic toxicity of un-ionized ammonia to early life-stages of endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) compared to the surrogate fathead minnow (Pimephales promelas).

    PubMed

    Fairchild, J F; Allert, A L; Sappington, L C; Waddell, B

    2005-10-01

    Ammonia-contaminated groundwater enters the Upper Colorado River from beneath the abandoned Moab Uranium Mill Tailings Pile near Moab, Utah. This reach of the Upper Colorado River was designated as critical habitat for four endangered fish species because it is one of the few existing areas with known spawning and rearing habitats. Un-ionized ammonia (NH3) concentrations frequently exceed 1.00 mg/L in backwaters adjacent to the tailings pile, which exceeds the Utah 30-d average chronic water quality criterion for un-ionized ammonia (0.07 mg/L NH3; temperature 20 degrees C; pH 8.2) by a factor of more than 10. However, there is little published information regarding the sensitivity of endangered fishes to ammonia. We conducted 28-d static renewal studies with post-swim-up larvae to determine the relative sensitivity of Colorado pikeminnow (Ptychocheilus lucius), razorback sucker (Xyrauchen texanus), and the standard surrogate fathead minnow (Pimephales promelas) to NH3. Chronic values (ChVs) for mortality and growth were determined as the geometric mean of the no observed effect concentration and the lowest observed effect concentration based on analysis of variance. The ChVs for growth of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.40, and 0.67 mg/L NH3, respectively. The ChVs for mortality of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.70, and 0.67 mg/L NH3, respectively. Therefore, the ChVs for mortality and growth were similar for fathead minnow and razorback sucker; however, the ChV for growth was lower than the ChV for mortality for Colorado pikeminnow. Maximum likelihood regression was used to calculate 28-d lethal concentrations (LCx) for each species. The 28-d LC50, LC20, and LC1 values for fathead minnow were 0.69, 0.42, and 0.13 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for Colorado pikeminnow were 0.76, 0.61, and 0.38 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for

  20. Chronic toxicity of un-ionized ammonia to early life-stages of endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) compared to the surrogate fathead minnow (Pimephales promelas)

    USGS Publications Warehouse

    Fairchild, J.F.; Allert, A.L.; Sappington, L.C.; Waddell, B.

    2005-01-01

    Ammonia-contaminated groundwater enters the Upper Colorado River from beneath the abandoned Moab Uranium Mill Tailings Pile near Moab, Utah. This reach of the Upper Colorado River was designated as critical habitat for four endangered fish species because it is one of the few existing areas with known spawning and rearing habitats. Un-ionized ammonia (NH3) concentrations frequently exceed 1.00 mg/L in backwaters adjacent to the tailings pile, which exceeds the Utah 30-d average chronic water quality criterion for un-ionized ammonia (0.07 mg/L NH3; temperature 20??C; pH 8.2) by a factor of more than 10. However, there is little published information regarding the sensitivity of endangered fishes to ammonia. We conducted 28-d static renewal studies with post-swim-up larvae to determine the relative sensitivity of Colorado pikeminnow (Ptychocheilus lucius), razorback sucker (Xyrauchen texanus), and the standard surrogate fathead minnow (Pimephales promelas) to NH3. Chronic values (ChVs) for mortality and growth were determined as the geometric mean of the no observed effect concentration and the lowest observed effect concentration based on analysis of variance. The ChVs for growth of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.40, and 0.67 mg/L NH3, respectively. The ChVs for mortality of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.70, and 0.67 mg/L NH3, respectively. Therefore, the ChVs for mortality and growth were similar for fathead minnow and razorback sucker; however, the ChV for growth was lower than the ChV for mortality for Colorado pikeminnow. Maximum likelihood regression was used to calculate 28-d lethal concentrations (LCx) for each species. The 28-d LC50, LC20, and LC1 values for fathead minnow were 0.69, 0.42, and 0.13 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for Colorado pikeminnow were 0.76, 0.61, and 0.38 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for razorback

  1. Chronic toxicity of un-ionized ammonia to early life-stages of endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) compared to the surrogate fathead minnow (Pimephales promelas).

    PubMed

    Fairchild, J F; Allert, A L; Sappington, L C; Waddell, B

    2005-10-01

    Ammonia-contaminated groundwater enters the Upper Colorado River from beneath the abandoned Moab Uranium Mill Tailings Pile near Moab, Utah. This reach of the Upper Colorado River was designated as critical habitat for four endangered fish species because it is one of the few existing areas with known spawning and rearing habitats. Un-ionized ammonia (NH3) concentrations frequently exceed 1.00 mg/L in backwaters adjacent to the tailings pile, which exceeds the Utah 30-d average chronic water quality criterion for un-ionized ammonia (0.07 mg/L NH3; temperature 20 degrees C; pH 8.2) by a factor of more than 10. However, there is little published information regarding the sensitivity of endangered fishes to ammonia. We conducted 28-d static renewal studies with post-swim-up larvae to determine the relative sensitivity of Colorado pikeminnow (Ptychocheilus lucius), razorback sucker (Xyrauchen texanus), and the standard surrogate fathead minnow (Pimephales promelas) to NH3. Chronic values (ChVs) for mortality and growth were determined as the geometric mean of the no observed effect concentration and the lowest observed effect concentration based on analysis of variance. The ChVs for growth of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.40, and 0.67 mg/L NH3, respectively. The ChVs for mortality of fathead minnow, Colorado pikeminnow, and razorback sucker were 0.43, 0.70, and 0.67 mg/L NH3, respectively. Therefore, the ChVs for mortality and growth were similar for fathead minnow and razorback sucker; however, the ChV for growth was lower than the ChV for mortality for Colorado pikeminnow. Maximum likelihood regression was used to calculate 28-d lethal concentrations (LCx) for each species. The 28-d LC50, LC20, and LC1 values for fathead minnow were 0.69, 0.42, and 0.13 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for Colorado pikeminnow were 0.76, 0.61, and 0.38 mg/L NH3, respectively. The 28-d LC50, LC20, and LC1 values for

  2. Validation of laboratory versus field avoidance behavior of schooling fathead minnows to heavy metal blends relative to acute toxicity during long term exposure

    SciTech Connect

    Hartwell, S.I.

    1985-01-01

    Avoidance and toxicity of four metals (relative proportions: 1.00 copper, 0.54 chromium, 1.85 arsenic, 0.38 selenium) were determined for schools of fathead minnows (Pimephalese promelas) in laboratory chamber, artificial stream and natural stream settings during continuous exposure to the metal blend. Laboratory avoidance responses were determined seasonally in a steep-gradient, laminar-flow chamber. Unexposed fish avoided 29 ug/L total metals. Fish exposed to 49 ug/L total metals for 3 months failed to avoid concentrations up to 245 ug/L total metals. Activity was not affected by long term exposure. Artificial stream avoidance responses were determined seasonally during 7 months of field laboratory holding in New River water for unexposed (control) fish and exposed (98 ug/L total metals) fish. In-stream avoidance responses were determined in the summer for unexposed (control) and exposed (98 ug/L total metals) fish in a second order tributary to the New River. Hardness, turbidity and physical setting are implicated as possible causative factors for differences between control fish responses tested in different seasons and locations. Laboratory exposed fish had a 96-hr LC50 1.25x higher than laboratory control fish. Control fish avoided metals levels at 0.4% of their 96-hr LC50. Field exposed fish had a 96-hr LC50 value 1.41x higher than field controls. Field control fish avoided metals levels between 0.7 and 2.5% of their 96-hr LC50 depending upon test location and season. There was no difference between the 96-hr LC50s of laboratory vs field control fish or between laboratory vs field exposed fish.

  3. Using a water-effect ratio approach to establish effects of an effluent-influenced stream on copper toxicity to the fathead minnow

    SciTech Connect

    Diamond, J.M.; Gerardi, C.; Leppo, E.; Miorelli, T.

    1997-07-01

    Water-effect ratio (WER) testing, examining the relative toxicity of copper in various dilutions of effluent and stream water as compared with laboratory dilution water, was conducted during January, April, and June, 1995, to assess the potential of seasonal and flow effects on site water quality and toxicity of copper to the fathead minnow. Total organic carbon (TOC) and dissolved solids were significantly related to effluent concentration in the site water, resulting in higher copper median lethal concentrations (LC50s) and higher WERs as effluent contribution in site water increased. Total recoverable copper LC50s were similar to dissolved copper LC50s in laboratory and upstream water tests, while effluent and stream water tests had significantly higher total recoverable than dissolved copper LC50s, suggesting more solids or complexing agents when effluent was present. The LC50 and WER for upstream water were significantly higher in April than in January, consistent with the higher TOC, alkalinity, and lower stream flow observed during April. The WER tests, using different proportions of upstream water and effluent in both January and April, indicated that total recoverable copper WER was predictable under a variety of stream flow conditions. Dissolved copper WERs were less predictable, in part because effluent and upstream water WERs were similar, particularly in April. Low-flow stream conditions appeared to be the limiting condition in terms of greatest copper toxicity at this site. Furthermore, winter low-flow conditions appeared to be more limiting than similar or even lower flows in spring or summer. This was probably due to the higher TOC and dissolved solids present in upstream water in the warmer seasons. All analyses indicated that copper was at least five times less toxic in the effluent-influenced stream water than in typical laboratory test dilution water.

  4. Metabolite profiles of repeatedly sampled urine from male fathead minnows (Pimephales promelas) contain unique lipid signatures following exposure to anti-androgens.

    PubMed

    Collette, Timothy W; Skelton, David M; Davis, John M; Cavallin, Jenna E; Jensen, Kathleen M; Kahl, Michael D; Villeneuve, Daniel L; Ankley, Gerald T; Martinović-Weigelt, Dalma; Ekman, Drew R

    2016-09-01

    The purpose of this study was twofold. First, we sought to identify candidate markers of exposure to anti-androgens by analyzing endogenous metabolite profiles in the urine of male fathead minnows (mFHM, Pimephales promelas). Based on earlier work, we hypothesized that unidentified lipids in the urine of mFHM were selectively responsive to exposure to androgen receptor antagonists, which is otherwise difficult to confirm using established fish toxicity assays. A second goal was to evaluate the feasibility of non-lethally and repeatedly sampling urine from individual mFHMs over the time course of response to a chemical exposure. Accordingly, we exposed mFHM to the model anti-androgens vinclozolin or flutamide. Urine was collected from each fish at 48hour intervals over the course of a 14day exposure. Parallel experiments were conducted with mFHM exposed to bisphenol A or control water. The frequent handling/sampling regime did not cause apparent adverse effects on the fish. Endogenous metabolite profiling was conducted with gas chromatography-mass spectrometry (GC-MS), which exhibited lower variation for the urinary metabolome than was found in earlier work with nuclear magnetic resonance (NMR) spectroscopy. Specifically, for inter- and intra-individual variations, the median spectrum-wide relative standard deviation (RSD) was 32.6% and 33.3%, respectively, for GC-MS analysis of urine from unexposed mFHM. These results compared favorably with similar measurements of urine from other model species, including the Sprague Dawley rat. In addition, GC-MS allowed us to identify several lipids (e.g., certain saturated fatty acids) in mFHM urine as candidate markers of exposure to androgen receptor antagonists. PMID:26810197

  5. Interactive effects of chronic waterborne copper and cadmium exposure on tissue-specific metal accumulation and reproduction in fathead minnow (Pimephales promelas).

    PubMed

    Driessnack, Melissa K; Matthews, Amber L; Raine, Jason C; Niyogi, Som

    2016-01-01

    The present study was carried out to examine the interactive effects of chronic waterborne copper (Cu) and cadmium (Cd) on tissue-specific metal accumulation and reproduction in fathead minnow (Pimephales promelas). Trios (1 male: 2 female; n=5) of fish were exposed for 21days to: (i) control (no added Cu or Cd), (ii) waterborne Cu (75μg/L), (iii) waterborne Cd (5μg/L), and (iv) Cu and Cd mixture (75 and 5μg/L, respectively). Reproductive output (cumulative egg production) was significantly reduced by Cu but not by Cd. Interestingly however, no spawning occurred in fish exposed to the mixture of waterborne Cu and Cd. In general, both Cu and Cd accumulation in target tissues (gill, liver, gonad and carcass) increased significantly in fish exposed to Cu and Cd mixture, and no interaction between Cu and Cd accumulation was observed in any tissues, except in the liver where Cu accumulation was significantly reduced by Cd. The expression of female hepatic estrogen receptor genes (ER-α and ER-β) was most significantly elevated in fish exposed to Cu and Cd mixture, whereas vitellogenin gene expression was reduced maximally in the same exposure. Similarly, the hepatic expression of the metallothionein gene was most significantly upregulated in fish exposed to Cu and Cd mixture. Moreover, the circulating estradiol level in females was significantly decreased only during the co-exposure of waterborne Cu and Cd. Overall, the present study indicates that the interaction of chronic waterborne Cu and Cd exposure may elicit greater than additive effect on reproductive output in fish. PMID:26498072

  6. Metabolite profiles of repeatedly sampled urine from male fathead minnows (Pimephales promelas) contain unique lipid signatures following exposure to anti-androgens.

    PubMed

    Collette, Timothy W; Skelton, David M; Davis, John M; Cavallin, Jenna E; Jensen, Kathleen M; Kahl, Michael D; Villeneuve, Daniel L; Ankley, Gerald T; Martinović-Weigelt, Dalma; Ekman, Drew R

    2016-09-01

    The purpose of this study was twofold. First, we sought to identify candidate markers of exposure to anti-androgens by analyzing endogenous metabolite profiles in the urine of male fathead minnows (mFHM, Pimephales promelas). Based on earlier work, we hypothesized that unidentified lipids in the urine of mFHM were selectively responsive to exposure to androgen receptor antagonists, which is otherwise difficult to confirm using established fish toxicity assays. A second goal was to evaluate the feasibility of non-lethally and repeatedly sampling urine from individual mFHMs over the time course of response to a chemical exposure. Accordingly, we exposed mFHM to the model anti-androgens vinclozolin or flutamide. Urine was collected from each fish at 48hour intervals over the course of a 14day exposure. Parallel experiments were conducted with mFHM exposed to bisphenol A or control water. The frequent handling/sampling regime did not cause apparent adverse effects on the fish. Endogenous metabolite profiling was conducted with gas chromatography-mass spectrometry (GC-MS), which exhibited lower variation for the urinary metabolome than was found in earlier work with nuclear magnetic resonance (NMR) spectroscopy. Specifically, for inter- and intra-individual variations, the median spectrum-wide relative standard deviation (RSD) was 32.6% and 33.3%, respectively, for GC-MS analysis of urine from unexposed mFHM. These results compared favorably with similar measurements of urine from other model species, including the Sprague Dawley rat. In addition, GC-MS allowed us to identify several lipids (e.g., certain saturated fatty acids) in mFHM urine as candidate markers of exposure to androgen receptor antagonists.

  7. Evaluation of the robustness of the fathead minnow, Pimephales promelas, larval survival and growth test, U.S. EPA method 1000.0

    SciTech Connect

    Pickering, Q.H.; Lazorchak, J.M.

    1995-04-01

    An intralaboratory study was conducted to evaluate the robustness of the Fathead minnow (Pimephales promelas) Larval Survival and Growth Test, Method 1000.0. Toxicity tests were conducted with the reference toxicants hexavalent chromium (Cr{sup 6+}) and copper (Cu), and the data were statistically analyzed using hypothesis testing. Differences in age, size, feeding regimes, and water quality did not cause more than a twofold difference in 13 subchronic values (SCVs) for Cr{sup 6+}. These tests involved side-by-side tests initiated with 1-, 4-, and 7-d larvae or initiated with 1-d larvae and two size groups of 4-d larvae fed differently. The mean SCV was 3,600 {mu}g Cr{sup 6+}/L, and the values ranged from 2,100 to 4,200 {mu}g Cr{sup 6+}/L. Eleven of these tests with a homogeneous variance gave an average minimum significant difference (MSD) of 14.3%. The no-observed-effect concentration (NOEC) for growth was always lower than the effect on survival. In the side-by-side tests with 1-, 4-, and 7-d larvae exposed in hard water the SCV was 35 {mu}g Cu/L for each age group. Except for one test with Cu in soft water, the effects of Cr{sup 6+} and Cu on growth were more sensitive than the effect on survival. These toxicity tests along with some nontoxicant studies indicated that reasonable differences in methods parameters did not cause any changes greater than a factor or two in analytical results despite the noise of biological variability.

  8. Changes in gene transcription and whole organism responses in larval fathead minnow (Pimephales promelas) following short-term exposure to the synthetic pyrethroid bifenthrin.

    PubMed

    Beggel, Sebastian; Connon, Richard; Werner, Inge; Geist, Juergen

    2011-09-01

    The combination of molecular and whole-organism endpoints in ecotoxicology provides valuable information about the ecological relevance of sublethal stressor effects in aquatic ecosystems such as those caused by the use of insecticides and translocation of their residues into surface waters. This study contributes knowledge about the sublethal effects of a common use insecticide, the synthetic pyrethroid bifenthrin, on larval fathead minnow (Pimephales promelas). Transcriptomic responses, assessed by quantitative real-time PCR, combined with individual effects on swimming performance were used to estimate the ecological relevance of insecticide impacts. Significant transcriptomic responses were observed at 0.07 μg L(-1) bifenthrin (lowest observed effect concentration, LOEC) but mostly followed a biphasic rather than a linear dose-response with increasing concentration. Transcript patterns for genes involved in detoxification, neuromuscular function and energy metabolism were linked to an impairment of swimming performance at ≥0.14 μg L(-1) bifenthrin. With increasing treatment concentration, a significant down-regulation was observed for genes coding for cyp3a, aspartoacylase, and creatine kinase, whereas metallothionein was up-regulated. Additionally, bifenthrin induced endocrine responses as evident from a significant up-regulation of vitellogenin and down-regulation of insuline-like growth factor transcripts. Recovery occurred after 6 days and was dependent on the magnitude of the initial stress. During the recovery period, down-regulation of vitellogenin was observed at lowest exposure concentrations. The data presented here emphasize that links can be made between gene transcription changes and behavioral responses which is of great value for the evaluation and interpretation of biomarker responses. PMID:21718662

  9. The genomic transcriptional response of female fathead minnows (Pimephales promelas) to an acute exposure to the androgen, 17β-trenbolone

    USGS Publications Warehouse

    Dorts, Jennifer; Richter, Catherine A.; Wright-Osment, Maureen K.; Ellersieck, Mark R.; Carter, Barbara J.; Tillitt, Donald E.

    2009-01-01

    We investigated the genomic transcriptional response of female fathead minnows (Pimephales promelas) to an acute (4 days) exposure to 0.1 or 1.0 ??g/L of 17??-trenbolone (TB), the active metabolite of an anabolic androgenic steroid used as a growth promoter in cattle and a contaminant of concern in aquatic systems. Our objectives were to investigate the gene expression profile induced by TB, define biomarkers of exposure to TB, and increase our understanding of the mechanisms of adverse effects of TB on fish reproduction. In female gonad tissue, microarray analysis using a 22 K oligonucleotide microarray (EcoArray Inc., Gainesville, FL) showed 99 significantly upregulated genes and 741 significantly downregulated genes in response to 1 ??g TB/L. In particular, hydroxysteroid (17??) dehydrogenase 12a (hsd17b12a), zona pellucida glycoprotein 2.2 (zp2.2), and protein inhibitor of activated STAT, 2 (pias2) were all downregulated in gonad. Q-PCR measurements in a larger sample set were consistent with the microarray results in the direction and magnitude of these changes in gene expression. However, several novel potential biomarkers were verified by Q-PCR in the same samples, but could not be validated in independent samples. In liver, Q-PCR measurements showed a significant decrease in vitellogenin 1 (vtg1) mRNA expression. In brain, cytochrome P450, family 19, subfamily A, polypeptide 1b (cyp19a1b, previously known as aromatase B) transcript levels were significantly reduced following TB exposure. Our study provides a candidate gene involved in mediating the action of TB, hsd17b12a, and two potential biomarkers sensitive to acute TB exposure, hepatic vtg1 and brain cyp19a1b.

  10. Interactive effects of chronic waterborne copper and cadmium exposure on tissue-specific metal accumulation and reproduction in fathead minnow (Pimephales promelas).

    PubMed

    Driessnack, Melissa K; Matthews, Amber L; Raine, Jason C; Niyogi, Som

    2016-01-01

    The present study was carried out to examine the interactive effects of chronic waterborne copper (Cu) and cadmium (Cd) on tissue-specific metal accumulation and reproduction in fathead minnow (Pimephales promelas). Trios (1 male: 2 female; n=5) of fish were exposed for 21days to: (i) control (no added Cu or Cd), (ii) waterborne Cu (75μg/L), (iii) waterborne Cd (5μg/L), and (iv) Cu and Cd mixture (75 and 5μg/L, respectively). Reproductive output (cumulative egg production) was significantly reduced by Cu but not by Cd. Interestingly however, no spawning occurred in fish exposed to the mixture of waterborne Cu and Cd. In general, both Cu and Cd accumulation in target tissues (gill, liver, gonad and carcass) increased significantly in fish exposed to Cu and Cd mixture, and no interaction between Cu and Cd accumulation was observed in any tissues, except in the liver where Cu accumulation was significantly reduced by Cd. The expression of female hepatic estrogen receptor genes (ER-α and ER-β) was most significantly elevated in fish exposed to Cu and Cd mixture, whereas vitellogenin gene expression was reduced maximally in the same exposure. Similarly, the hepatic expression of the metallothionein gene was most significantly upregulated in fish exposed to Cu and Cd mixture. Moreover, the circulating estradiol level in females was significantly decreased only during the co-exposure of waterborne Cu and Cd. Overall, the present study indicates that the interaction of chronic waterborne Cu and Cd exposure may elicit greater than additive effect on reproductive output in fish.

  11. Developmental profiles and expression of the DNA methyltransferase genes in the fathead minnow (Pimephales promelas) following exposure to di-2-ethylhexyl phthalate.

    PubMed

    Wood, Richard K; Crowley, Emma; Martyniuk, Christopher J

    2016-02-01

    DNA methylation is an epigenetic regulator of gene expression, and this process has been shown to be disrupted by environmental contaminants. Di-2-(ethylhexyl) phthalate (DEHP) and related phthalate esters have been shown to affect development in early life stages of fish and can alter genomic methylation patterns in vertebrates. The objectives of this study were the following: (1) Describe the expression patterns of the DNA methyltransferase (dnmt) genes during early fathead minnow (FHM) development. These genes are critical for methylation and imprinting during development. (2) Determine the effects of DEHP on the development of FHM larvae [1 and 14 days post-hatch (dph)]. (3) Determine the effect of DEHP on dnmt expression and global methylation status in larval FHM. FHMs were first collected over a developmental time course [1, 3, 5, 6, and 14 days post-fertilization (dpf)] to investigate the expression patterns of five dnmt isoforms. The expression of dnmt1 and dnmt7 was relatively high in embryos at 1 dpf but was variable in expression, and these transcripts were later expressed at a lower level (>3 dpf); dnmt3 was significantly higher in embryos at 1 dpf compared to those at 3 dpf. Dnmt6 showed more of a constitutive pattern of expression during the first 2 weeks of development, and the mRNA levels of dnmt8 were higher in embryos at 5 and 6 dpf compared to those at 1 and 3 dpf, corresponding to the hatching period of the embryos. A waterborne exposure to three concentrations of DEHP (1, 10 and 100 µg/L) was conducted on 1-day FHM embryos for 24 h and on larval fish for 2 weeks, ending at 14 dpf. DEHP did not negatively affect survival, hatch rate, or the expression of dnmt isoforms in FHMs. There were no differences in global cytosine methylation following DEHP treatments in 14 dpf larvae, suggesting that environmentally relevant levels of DEHP may not affect global methylation at this stage of FHM development. However, additional targeted methylome studies

  12. A time-course analysis of effects of the steroidogenesis inhibitor ketoconazole on components of the hypothalamic-pituitary-gonadal axis of fathead minnows.

    PubMed

    Ankley, Gerald T; Cavallin, Jenna E; Durhan, Elizabeth J; Jensen, Kathleen M; Kahl, Michael D; Makynen, Elizabeth A; Thomas, Linnea M; Wehmas, Leah C; Villeneuve, Daniel L

    2012-06-15

    The objective of this study was to evaluate temporal effects of the model steroidogenesis inhibitor ketoconazole (KTC) on aspects of reproductive endocrine function controlled by the hypothalamic-pituitary-gonadal (HPG) axis in the fathead minnow (Pimephales promelas). Ketoconazole inhibits the activity of two cytochrome P450s (CYPs) key to sex steroid production in vertebrates, CYP11a (cholesterol side chain cleavage) and CYP17 (c17α-hydroxylase/17, 20-lyase). Sexually mature fish were exposed to water-borne KTC (30 or 300 μg/L) in a flow-through system for up to 8d, following which animals were allowed to recover in clean water. Fish were sampled after 1, 4 and 8d of exposure, and after 1, 8 and 16d of recovery. A shorter-term time-course experiment also was conducted in which females were sampled on seven occasions during a 12h KTC exposure. Ketoconazole consistently depressed ex vivo gonadal synthesis of testosterone (T) in both sexes, and 17β-estradiol (E2) in females during both exposure and recovery phases of the time-course studies. Effects on ex vivo steroidogenesis in females occurred within as little as 1h of exposure. Plasma concentrations of T in males and E2 in females also were depressed by exposure to KTC, but these decreases did not persist to the same degree as observed for the ex vivo effects. In females, after decreases within 12h, plasma E2 concentrations were similar to (or greater than) controls at 24h of exposure, while in males, plasma T returned to levels comparable to controls within 1d of cessation of KTC exposure. The discrepancy between the ex vivo and in vivo data at later stages in the test is consistent with some type of compensatory response to KTC in fish. However, we were unable to ascertain the mechanistic basis for such a response. For example, although a number of genes related to steroid synthesis (e.g., cyp11a, cyp17) were up-regulated in the gonads of both males and females during the exposure and early recovery phases

  13. Environmental concentrations of the selective serotonin reuptake inhibitor fluoxetine impact specific behaviors involved in reproduction, feeding and predator avoidance in the fish Pimephales promelas (fathead minnow)

    PubMed Central

    Weinberger, Joel; Klaper, Rebecca

    2014-01-01

    Pharmaceuticals and personal care products (PPCP) have been found in surface waters worldwide, but little is understood of their effects on the wildlife that inhabit these waters. Fluoxetine (Prozac; Eli Lilly), a highly prescribed selective serotonin reuptake inhibitor (SSRI), is a commonly found PPCP in surface water. The purpose of this project was to determine if environmentally relevant concentrations of fluoxetine impact behavior that is important for population survival in native fish species, including reproduction, feeding and predator avoidance. Chronic 4-week exposures were conducted with doses ranging from 100 ng/L to 100 μg/L to cover a range of environmentally relevant concentrations up to higher concentrations comparable to other published studies with the same drug that have documented various physiological impacts. Pimephales promelas (fathead minnow), a species native to North America, was used as it conducts a range of specific mating behaviors and therefore serves as an excellent model of specific impacts on brain function. Fluoxetine concentrations as low as 1 μg/L, a concentration that has been found in many freshwater environments, were found to significantly impact mating behavior, specifically nest building and defending in male fish. Males were also found to display aggression, isolation, and repetitive behaviors at higher concentrations. Female mating behavior was largely unaffected. In addition, predator avoidance behaviors in males and females were also impacted at 1 μg/L. Feeding was impacted at 10 μg/L and in the highest exposure (100 μg/L), egg production was limited by deaths of females due to significant male aggressive behaviors in first two weeks of exposure. Specific behavioral changes occurred at each concentration (most noticeably 1 μg/L and 100 μg/L) indicating a dose dependent effect that triggered different responses at lower exposures versus higher exposures or differential impacts of dose depending on brain region

  14. A mixture of an environmentally realistic concentration of a phthalate and herbicide reduces testosterone in male fathead minnow (Pimephales promelas) through a novel mechanism of action

    PubMed Central

    Crago, Jordan; Klaper, Rebecca

    2014-01-01

    Several chemicals that are used by humans, such as pesticides and plastics, are released into the aquatic environment through wastewater and runoff and have been shown to be potent disruptors of androgen synthesis at high concentrations. Although many of these chemicals have been studied in isolation, a large amount of uncertainty remains over how fish respond to low concentrations of anti-androgenic mixtures, which more accurately reflects how such chemicals are present in the aquatic environment. In this study male fathead minnows (FHM) (Pimephales promelas) were exposed to environmentally relevant concentrations of two anti-androgens, the herbicide linuron, and the plasticizer di(2-ethylhexyl) phthalate (DEHP) individually and as part of a mixture of the two for a 28-day period. At the end of this period there was a reduction in plasma testosterone (T) concentrations in male FHM exposed to the mixture, but not in FHM exposed individually to linuron or DEHP or the control FHM. There was also a significant reduction in 17β-estradiol (E2) in the DEHP-only and mixture exposed groups as compared to the control. Contrary to what has been previously published for these two chemicals in mammals, the lower plasma T concentrations in male FHM exposed to the mixture was not a result of the inhibition of genes involved in steroidogenesis; nor due to an increase in the expression of genes associated with peroxisome proliferation. Rather, an increase in relative transcript abundance for CYP3A4 in the liver and androgen-and estrogen-specific SULT2A1 and SULT1st2 in the testes provides evidence that the decrease in plasma T and E2 may be linked to increased steroid catabolism. Feedback from the pituitary is not repressed as the relative expression of follicle stimulating hormone β-subunit mRNA transcript levels in the brain was significantly higher in both DEHP and mixture exposed FHM. In addition, luteinizing hormone β-subunit mRNA transcript levels increased but were not

  15. Influence of elevated alkalinity and natural organic matter (NOM) on tissue-specific metal accumulation and reproductive performance in fathead minnows during chronic, multi-trophic exposures to a metal mine effluent.

    PubMed

    Ouellet, Jacob D; Dubé, Monique G; Niyogi, Som

    2013-09-01

    Metal bioavailability in aquatic organisms is known to be influenced by various water chemistry parameters. The present study examined the influence of alkalinity and natural organic matter (NOM) on tissue-specific metal accumulation and reproductive performance of fathead minnows (Pimephales promelas) during environmentally relevant chronic exposures to a metal mine effluent (MME). Sodium bicarbonate (NaHCO3) or NOM (as commercial humic acid) were added to a Canadian MME [45 percent process water effluent (PWE)] in order to evaluate whether increases in alkalinity (3-4 fold) or NOM (~1.5-3mg/L dissolved organic carbon) would reduce metal accumulation and mitigate reproductive toxicity in fathead minnows during a 21-day multi-trophic exposure. Eleven metals (barium, boron, cobalt, copper, lithium, manganese, molybdenum, nickel, rubidium, selenium, and strontium) were elevated in the 45 percent PWE relative to the reference water. Exposure to the unmodified 45 percent PWE resulted in a decrease of fathead minnow egg production (~300 fewer eggs/pair) relative to the unmodified reference water, over the 21-day exposure period. Water chemistry modifications produced a modest decrease in free ion activity of some metals (as shown by MINTEQ, Version 3) in the 45 percent PWE exposure water, but did not alter the metal burden in the treatment-matched larval Chironomus dilutus (the food source of fish during exposure). The tissue-specific metal accumulation increased in fish exposed to the 45 percent PWE relative to the reference water, irrespective of water chemistry modifications, and the tissue metal concentrations were found to be similar between fish in the unmodified and modified 45 percent PWE (higher alkalinity or NOM) treatments. Interestingly however, increased alkalinity and NOM markedly improved fish egg production both in the reference water (~500 and ~590 additional eggs/pair, respectively) and 45 percent PWE treatments (~570 and ~260 additional eggs

  16. Sensitivity of the vitellogenin assay: ability to discriminate among exposure concentrations in adult fathead minnow

    EPA Science Inventory

    Vitellogenin is often used to infer exposure of an organism to estrogenic substances. Vitellogenin gene induction and protein levels increase, up to a point, with concentration of estrogen and duration of exposure. A biomarker such as vitellogenin should exhibit sufficient sens...

  17. RELATIONSHIP BETWEEN BRAIN AND OVARY AROMATASE ACTIVITY AND ISOFORM-SPECIFIC AROMATASE MRNA EXPRESSION IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS) - JOURNAL ARTICLE

    EPA Science Inventory

    There is growing evidence that some chemicals present in the environment have the capacity to inhibit, or potentially induce, aromatase activity. This study compared aromatase activities and isoform-specific mRNA expression in brain and ovary tissue from non-exposed fathead minn...

  18. Fathead fecundity study

    SciTech Connect

    Barman, M.A.E.; Geis, S.; Repavich, W.; Schappe, K.

    1995-12-31

    Fathead minnows (Pimephales promelas) are cultured in controlled laboratory settings for use in aquatic toxicity testing. Culturing is done to maintain a continuous supply of organisms of all ages; breeders, juveniles and larvae. This study is designed to determine the age at which peak egg production occurs. Fish are paired, one male to one female, at three to four months of age. Daily egg production is recorded and graphed. The graph of egg production vs. fish age will determine the age at which peak egg production occurs. The results of this study will provide information for more efficient use of lab space and staff, while maximizing egg production.

  19. Studies of the environmental fate and effect of aircraft deicing fluids: Detection of 5-methyl-1H-benzotriazole in the fathead minnow (Pimephales promelas)

    USGS Publications Warehouse

    Cancilla, Devon A.; Baird, J.C.; Geis, S.W.; Corsi, Steven R.

    2003-01-01

    This paper presents the results of a number of field and laboratory studies to evaluate the environmental impact of aircraft deicing and anti-icing fluids (ADAFs) on aquatic systems. Both 5-methyl-1H-benzotriazole (5-MeBt) and 4-methyl-1H-benzotriazole (4-MeBt), known additives to ADAFs, were found in whole-tissue extracts from minnows placed downstream of an effluent outfall that receives ADAF contaminated runoff from General Mitchell International Airport (Milwaukee, WI, USA). Neither of these compounds was detected in tissues from minnows placed upstream from the airport. A toxicity assessment of water collected during the minnow exposure studies utilizing Hyalella azteca, Pimephales promelas, and Ceriodaphnia dubia showed greater toxicity in a secondary airport outfall containing ADAFs when compared to upstream non-ADAF-contaminated samples. In two 28-d static renewal tests using 5-MeBt laboratory-fortified waters, 5-MeBt was detected in whole-tissue extracts of minnows at all concentrations tested. In studies using laboratory water fortified with 5-MeBt, the median lethal concentration (LC50) of 5-MeBt for P. promelas was found to be 22.0 mg/L. The LC50 for C. dubia to 5-MeBt laboratory-fortified water was found to be 81.3 mg/L. The 25% inhibition concentration (IC25) of 5-MeBt for the green alga Selenastrum capricornutum was 23.2 mg/L, and the average median effective concentration (EC50) for Microtox?? was 4.25 mg/L. The results of these field and lab studies indicate that additives, other than glycols, used in aircraft deicing fluids can be found in aquatic systems and may be of greater risk than previously believed.

  20. Minnows get columnaris too; copper sulfate works!

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to compare the therapeutic effects of copper sulfate (CuSO4), when delivered in either a flow-through or static system, on the survival of golden shiner (Notemigonus crysoleucas; Fig. 1A) and fathead minnow (Pimephales promelas; Fig. 1B) infected with Flavobacterium columnare (...

  1. CHRONIC EFFECTS OF THE HERBICIDE DIURON ON FRESHWATER CLADOCERANS,AMPHIPODS,MIDGES,MINNOWS,WORMS, AND SNAILS

    EPA Science Inventory

    The chronic effects of the herbicide diuron on survival and reproduction of Daphnia pulex, and survival and growth of the amphipod Hyalella azteca, the midge Chironomus tentans, juvenile and embro/larval fathead minnows, Pimephales promelas, annelid worms, Lumbriculus variegatus,...

  2. Cloning and characterization of cDNAs for hormones and/or receptors of growth hormone, insulin-like growth factor-I, thyroid hormone, and corticosteroid and the gender-, tissue-, and developmental-specific expression of their mRNA transcripts in fathead minnow (Pimephales promelas).

    PubMed

    Filby, Amy L; Tyler, Charles R

    2007-01-01

    Growth hormone (GH), insulin-like growth factor-I (IGF-I), thyroid hormones, and corticosteroids play central roles in a wide range of body functions but, in fish, information on their interactions is limited. These axes of the endocrine system are also potential targets for disruption of signaling pathways by hormone-mimicking chemicals, but have received little study. Molecular approaches offer an effective way to help unravel these endocrine interactions but require the appropriate gene-specific assays to do so. In this study, the cDNAs for a suite of hormones and/or receptors involved in signaling for the effects of GH and IGF-I [GH, GH receptor (GHR), IGF-I, IGF-I receptor (IGF-IR)], thyroid hormones [thyroid hormone receptor alpha (TRalpha) and beta (TRbeta)], and corticosteroids [glucocorticoid receptor (GR)] were cloned from the fathead minnow (Pimephales promelas; fhm), and the tissue-, developmental-, and gender-related expression of their mRNA transcripts established. By polymerase chain reaction (PCR) strategy, we obtained full-length 1123-bp GH, 817-bp IGF-I, 1584-bp TRbeta, and 2571-bp GR cDNAs, coding for 210 amino acid (aa) GH, 161 aa IGF-I, 378 aa TRbeta, and 745 aa GR putative proteins, and partial-length 158-bp GHR, 811-bp IGF-IR, and 446-bp TRalpha cDNAs. Real-time PCR analyses revealed broad tissue expression for the target mRNAs; all targets were expressed in brain, pituitary, gill, liver, gonad, intestine, and muscle, with the exception of GH that was expressed only in the pituitary and gonad. Expression patterns in both juvenile and adult fhm were complex, with both temporal-, tissue-, and sex-specific characteristics. For example, hepatic expressions of GHR, IGF-I, and IGF-IR were far higher in males than in females, possibly reflecting the sex-related dimorphism in growth that occurs in this species, and TRalpha and TRbeta showed divergent expression patterns during development (where TRbeta predominated) and in adult tissues implying some

  3. Evaluation of whole-mount in situ hybridization as a tool for pathway-based toxicological research with early-life stage fathead minnows

    EPA Science Inventory

    Early-life stage fish can be more sensitive to chemical exposure than adult fish. Therefore, determining possible adverse outcome pathways (AOPs) for early-life stages is crucial. To determine chemical effects and/or mechanisms of action in exposed fish embryos and larvae, whole-...

  4. Evaluation of whole mount in situ hybridization as a tool for pathway-based toxicological research in early-life stage fathead minnows (poster)

    EPA Science Inventory

    Early-life stage fish can be more sensitive to chemical exposure than mature, adult fish. Therefore, defining adverse outcome pathways (AOPs) relevant to early-life stages is critical for linking perturbations of key events during fish development to potential adverse outcomes of...

  5. Evaluation of whole mount in situ hybridization as a tool for pathway-based toxicological research in early-life stage fathead minnows

    EPA Science Inventory

    Early-life stage fish can be more sensitive to chemical exposure than mature, adult fish. Therefore, defining adverse outcome pathways (AOPs) relevant to early-life stages is critical for linking perturbations of key events during fish development to potential adverse outcomes of...

  6. Use of ecotoxicological and avoidance data to assess effects of hazardous materials on fish. [Minnow and trout

    SciTech Connect

    Gray, R.H.; Dauble, D.D.; Skaliski, J.R.

    1983-11-01

    Assessing potential environmental effects from accidential release of hazardous materials to aquatic habitats is often based on laboratory-derived tolerance data and assumptions of organism exposure. This approach usually represents worst-case conditions and does not consider the adaptive behavior of mobil organisms such as fish, which may modify actual exposures. We conducted behavioral response studies as part of a larger effort to assess the fate and effects of organically complex, coal-derived liquids in the aquatic environment. A nine-chambered circular apparatus (rosette) was used to test the ability of groups of adult fathead minnow (Pimephales promelas) and juvenile rainbow trout (Salmo gairdneri) to detect and avoid various concentrations of the water-soluble fraction (WSF) of a coal liquid. Fathead minnow avoided constituent concentrations of the WSF that were acutely toxic, but did not avoid concentrations known experimentally to affect growth and reproduction. In contrast, rainbow trout did not avoid the toxicant at any concentration, despite mortalities of up to 50% of some test groups. A conceptual model is presented that links avoidance and toxicological data, and allows a more realistic environmental assessment than can presently be obtained with toxicity data alone. 25 references, 5 figures.

  7. Histological alternation and vitellogenin induction in adult rare minnow (Gobiocypris rarus) after exposure to ethynylestradiol and nonylphenol

    USGS Publications Warehouse

    Zha, J.; Wang, Z.; Wang, N.; Ingersoll, C.

    2007-01-01

    Adult rare minnow (Gobiocypris rarus) were exposed to 0, 1, 5, and 25 ng/l (nominal concentrations) of 17??-ethynylestradiol (EE2) and 3, 10, and 30 ??g/l (nominal concentrations) of 4-nonylphenol (NP) under flow-through conditions for a period of 28 d. Low mortality was observed at 5 and 25 ng/l EE2 and the growth of fish reduced significantly at 25 ng/l EE2 compared to controls. However, the gonadosomatic indices (GSI) of male fish were significantly higher in 1 ng/l EE2 treatments and in 10 and 30 ??g/l NP treatments (p < 0.05). Renal somatic indices (RSI) of male fish in EE2 treatments were significantly higher than those in controls (p < 0.05). In contrast, significantly decreased GSI and RSI of female fish could only be observed in 5 and 25 ng/l EE2 treatments (p < 0.05). Hepatosomatic indices (HSI) of male fish were significantly higher in 25 ng/l EE2 treatments. However, significantly increased of HSI of female fish could only be observed in 1 ng/l EE2 treatments. Plasma vitellogenin (VTG) induction could be observed in males after exposed to different concentrations of EE2 and NP, and plasma VTG concentrations in females exposed to 5 and 25 ng/l EE2 were also significantly higher than in controls (p < 0.05). At level higher than 5 ng/l EE2 or 30 ??g/l NP, hepatic tissue and renal tissue impairment of males could be observed. The pathological male liver was associated with a hypertrophy of hepatocytes and damages to cellar structure and accumulated eosinophilic material. Renal tissue showed different pathological effects which was reflected by accumulated eosinophilic material, hemorrhages within the kidney tubules and hypertrophy of the tubular epithelia. Also at these levels of exposure, feminization of male fish could be noticed and parts of males manifested the testis-ova phenomenon. Ovaries of female rare minnow in 25 ng/l EE2 treatment group were degenerated. Therefore when exposed to EE2 and NP even at environmental observed concentrations, adverse

  8. Low-dose bisphenol A disrupts gonad development and steroidogenic genes expression in adult female rare minnow Gobiocypris rarus.

    PubMed

    Zhang, Yingying; Gao, Jiancao; Xu, Peng; Yuan, Cong; Qin, Fang; Liu, Shaozhen; Zheng, Yao; Yang, Yanping; Wang, Zaizhao

    2014-10-01

    Bisphenol A (BPA), an estrogenic monomer, has attracted many researchers to study its adverse effects in animal reproduction, especially in fish. To explore the effects of low dose BPA on adult female rare minnow Gobiocypris rarus, we exposed the fish to BPA at nominal concentrations of 5, 15, and 50 μg L(-1) for 14 and 35 d. The 35-d BPA exposure at 50 μg L(-1) had obviously suppressive effects on oocyte development, and BPA at all the three concentrations in both exposure durations of 14 and 35 d had stimulative effects on hepatic vitellogenin (vtg) transcription. BPA at lower concentrations (5 and 15 μg L(-1)) exhibited stimulative effects on the expressions of ovarian steroidogenic genes while at higher concentration (50 μg L(-1)) displayed inhibitive effects. Analysis of ovarian steroidogenic genes 5'-flanking regions and mRNA expressions of their potential regulatory factors revealed that the BPA-mediated actions on steroidogenesis in G. rarus ovary probably involve estrogen receptor (Esr) and androgen receptor (Ar) signaling, nuclear receptor subfamily 5, group A, number 1 (Nr5a1) pathway, and epigenetic regulation. PMID:25048937

  9. Behind the scene with the fathead team: Part III. Molecular, biochemical, and in vitro analyses

    EPA Science Inventory

    As part of a research team focused on aquatic toxicity testing using fathead minnows as a model species, this presentation is the third in the three-part series, giving an overview of the types of field and laboratory studies as well as sample processing our team conducts at the ...

  10. Butachlor causes disruption of HPG and HPT axes in adult female rare minnow (Gobiocypris rarus).

    PubMed

    Zhu, Lifei; Li, Wei; Zha, Jinmiao; Wang, Miao; Yuan, Lilai; Wang, Zijian

    2014-09-25

    Butachlor is a chloroacetamide herbicide widely used in Asia, and may enter the aquatic environment through agricultural application. In this study, plasma VTG and hormone levels (E2, 11-KT, T3 and T4) were determined after the female rare minnow (Gobiocypris rarus) was exposed to butachlor at environmental relevant concentrations (0, 0.1, 1, and 10μg/L) for 40days. The mRNA levels of the HPG axis-related genes (gnrh, erα, vtg, star, lhr, 3β-hsd, cyp11a, cyp17, cyp19a and cyp19b), and the HPT axis-related genes (trα, dio1, dio2, and dio3) were quantified after 20 and 40days exposure to butachlor. For the HPG axis, the plasma 11-KT was increased at exposure concentration of 10μg/L, and VTG was significantly decreased at 1μg/L. Functional genes like gnrh and cyp19b in the brains, star, lhr, cyp11a, 3β-hsd, and cyp19a in the ovaries, and erα and vtg in livers were up-regulated. For the HPT axis, the results showed that plasma T4 levels were significantly increased, the gene expression of dio1 was up-regulated, dio2 showed no significant variation, and dio3 was down-regulated in the livers. These results indicated that butachlor may promote the accumulation of T4 in fish through inactive deiodinase type 3. The transcription of HPG axis-related genes could serve as an auto-regulation of hormone levels after exposure to butachlor. Furthermore, the activation of gnrh may play an important role as a feed-back mechanism in the regulation of hormone levels and crosstalk of endocrine axes.

  11. Modulation of estrogenic exposure effects mediated through temperature and dietary regimens in male fat head minnows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A plethora of studies has examined the biological effects of environmental estrogens on fathead minnows. However, in many cases results from environmental studies do not match the expectations from prior laboratory exposures, which usually are designed to minimize confounding factors such as temper...

  12. Enhanced GSH synthesis by Bisphenol A exposure promoted DNA methylation process in the testes of adult rare minnow Gobiocypris rarus.

    PubMed

    Yuan, Cong; Zhang, Yingying; Liu, Yan; Zhang, Ting; Wang, Zaizhao

    2016-09-01

    DNA methylation is a commonly studied epigenetic modification. The mechanism of BPA on DNA methylation is poorly understood. The present study aims to explore whether GSH synthesis affects DNA methylation in the testes of adult male rare minnow Gobiocypris rarus in response to Bisphenol A (BPA). Male G. rarus was exposed to 1, 15 and 225μgL(-1) BPA for 7 days. The levels of global DNA methylation, hydrogen peroxide (H2O2) and glutathione (GSH) in the testes were analyzed. Meanwhile, the levels of enzymes involved in DNA methylation and de novo GSH synthesis, and the substrate contents for GSH production were measured. Furthermore, gene expression profiles of the corresponding genes of all studied enzymes were analyzed. Results indicated that BPA at 15 and 225μgL(-1) caused hypermethylation of global DNA in the testes. The 15μgL(-1) BPA resulted in significant decrease of ten-eleven translocation proteins (TETs) while 225μgL(-1) BPA caused significant increase of DNA methyltransferase proteins (DNMTs). Moreover, 225μgL(-1) BPA caused significant increase of H2O2 and GSH levels, and the de novo GSH synthesis was enhanced. These results indicated that the significant decrease of the level of TETs may be sufficient to cause the DNA hypermethylation by 15μgL(-1) BPA. However, the significantly increased of DNMTs contributed to the significant increase of DNA methylation levels by 225μgL(-1) BPA. Moreover, the elevated de novo GSH synthesis may promote the DNA methylation process. PMID:27474941

  13. EFFECTS OF TRENBOLONE ON EXPRESSION OF ESTROGEN-RESPONSIVE PLASMA PROTEINS IN ADULT SHEEPSHEAD MINNOW, (CYPRINODON VARIEGATUS)

    EPA Science Inventory

    Protein profiling can be used for detection of biomarkers that can be applied diagnostically to screen chemicals for endocrine modifying activity. In previous studies using sheepshead minnows (SHM), mass spectral analysis detected four peptides (2950.5, 2972.5, 3003.4, 3025.5 m/z...

  14. Behind the scene with the fathead team: Part I. Caged fish for assessment of chemicals in the environment

    EPA Science Inventory

    As part of a research team focused on aquatic toxicity testing using fathead minnows as a model species, this presentation is the first of a three-part series, giving an overview of the types of field and laboratory studies as well as sample processing our team conducts at the U....

  15. SCREENING LEVEL REPRODUCTION ASSAY WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    There has been recent concern for the potential effects of endocrine disrupting chemicals (EDCs) on reproduction and development of humans and wildlife species. The U.S. Environment Protection Agency (EPA) has identified EDC issues as one of six high priority research areas. Furt...

  16. GENETIC VARIATION FOR COPPER RESISTANCE IN FATHEAD MINNOW TOXICITY TESTS

    EPA Science Inventory

    Unexplained variation in the results of aquatic organism toxicity tests is a consistently observed and troubling phenomenon. Possible sources of variation include differences in condition or nutritional status of the population prior to the test, as well as age, density and hand...

  17. A Computational Model for Oocyte Growth Dynamics in Fathead Minnows

    EPA Science Inventory

    Molecular biomarkers have been used in ecotoxicological studies to evaluate the effects of endocrine disrupting chemicals in fish. Changes in these molecular biomarkers must then be linked to the effects upon reproduction in individuals, and subsequently populations. To meet th...

  18. EE2 Changes Gene Expression in Fathead Minnow Testis

    EPA Science Inventory

    Environmental estrogens have been implicated in altering reproductive health of aquatic animals. Early studies of sewage treatment effluents attributed the feminization of male fish to exposure to mixtures of natural and synthetic estrogens. One of the most potent estrogens kno...

  19. Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode cercariae.

    PubMed

    Stumbo, Anthony D; James, Clayton T; Goater, Cameron P; Wisenden, Brian D; Cotter, Sheena

    2012-11-01

    1. Individuals that live in groups benefit from increased foraging success and decreased predation. Protection from some types of parasites may provide an additional benefit of group-living. For fish, the extent to which shoaling can reduce an individual's risk of exposure to the infective stages of parasites is unknown. 2. We tested for antiparasite benefits of shoaling in fathead minnows exposed to larvae (cercariae) of two of their most common species of trematode, Ornithodiplostomum ptychocheilus and Posthodiplostomum minimum. As developing stages (metacercariae) of these trematodes cause reductions in minnow activity, growth and survival, natural selection should favour the evolution of cercariae-avoidance behaviours. 3. We evaluated shoal dimensions in groups of minnows exposed to O. ptychocheilus and to other chemical/physical stimuli within aquaria. To compare risk of exposure in shoaling vs. non-shoaling fish, we confined groups of minnows into mesh cages in outdoor mesocosms, exposed them to cercariae, then compared mean worm numbers in grouped vs. solitary fish. Lastly, we tested whether fish located within the centre of an artificial shoal reduced their risk of cercariae exposure compared with those along peripheral edges. 4. Minnows distinguished infective cercariae from other potential aquatic threats and responded with activity that reduced the 2-dimensional area of their shoals 15-fold compared with water-only controls. Fish confined within artificial shoals had 3-fold fewer worms than single fish and minnows located within the centre of artificial shoals had significantly fewer worms than those without peripheral minnows. 5. These results show that shoaling reduces a minnows' risk of exposure to cercariae, either directly via detection of cercariae in the water column followed by behavioural avoidance or indirectly via behaviour-mediated differences in exposure between shoaling vs. non-shoaling fish.

  20. Behind the scene with the fathead team: Part II. In-lab flow through exposures and “omics” to complement effects based monitoring in the Duluth-Superior Harbor.

    EPA Science Inventory

    As part of a research team focused on aquatic toxicity testing using fathead minnows as a model species, this presentation is the second of a three-part series, giving an overview of the types of field and laboratory studies as well as sample processing our team conducts at the U...

  1. Metformin Exposure at Environmentally Relevant Concentrations Causes Potential Endocrine Disruption in Adult Male Fish

    PubMed Central

    Niemuth, Nicholas J; Jordan, Renee; Crago, Jordan; Blanksma, Chad; Johnson, Rodney; Klaper, Rebecca D

    2015-01-01

    Pharmaceuticals and personal care products (PPCPs) are emerging contaminants that have been found ubiquitously in wastewater and surface waters around the world. A major source of these compounds is incomplete metabolism in humans and subsequent excretion in human waste, resulting in discharge into surface waters by wastewater treatment plant (WWTP) effluent. One pharmaceutical found in particularly high abundance in recent WWTP effluent and surface water studies is metformin, one of the world's most widely prescribed antidiabetic drugs. Interactions between insulin signaling and steroidogenesis suggest potential endocrine-disrupting effects of metformin found in the aquatic environment. Adult fathead minnows (Pimephales promelas) were chronically exposed to metformin for 4 wk, at 40 µg/L, a level similar to the average found in WWTP effluent in Milwaukee, Wisconsin, USA. Genetic endpoints related to metabolism and endocrine function as well as reproduction-related endpoints were examined. Metformin treatment induced significant up-regulation of messenger ribonucleic acid (mRNA) encoding the egg-protein vitellogenin in male fish, an indication of endocrine disruption. The present study, the first to study the effects of environmentally relevant metformin exposure in fathead minnows, demonstrates the need for further study of the endocrine-disrupting effects of metformin in aquatic organisms. Environ Toxicol Chem 2014;9999:1–6. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC. PMID:25358780

  2. Targeting neurotrophic factors and their receptors, but not cholinesterase or neurotransmitter, in the neurotoxicity of TDCPP in Chinese rare minnow adults (Gobiocypris rarus).

    PubMed

    Yuan, Lilai; Li, Jiasu; Zha, Jinmiao; Wang, Zijian

    2016-01-01

    Organophosphate flame retardants (OPFRs) have been detected at high concentrations in various environmental and biotic samples, but little is known about their toxicity. In this study, the potential neurotoxicity of three OPFRs (TCEP, TDCPP, and TPP) and Chlorpyrifos (CPF, an organophosphate pesticide) were compared in Chinese rare minnow using an acute toxicity test and a 21-day fish assay. The acute test demonstrated significant inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) by CPF. Although significant AChE inhibition at high concentration of TPP was also observed, none of the OPFRs had effects similar to CPF on these enzymes, indicating that their acute toxicities to Chinese rare minnow may be unrelated to cholinesterase inhibition. In addition, the 21-day fish assay with TDCPP demonstrated no significant effects on cholinesterase activities or neurotransmitter levels. Nonetheless, this OPFR exhibited widespread effects on the neurotrophic factors and their receptors (e.g., ntf3, ntrk1, ntrk2, ngfr, and fgf2, fgf11, fgf22, fgfr4), indicating that TDCPP or other OPFRs may elicit neurological effects by targeting neurotrophic factors and their receptors in Chinese rare minnow. PMID:26552522

  3. Molecular characterization of gdf9 and bmp15 genes in rare minnow Gobiocypris rarus and their expression upon bisphenol A exposure in adult females.

    PubMed

    Zhang, Yingying; Yuan, Cong; Qin, Fang; Hu, Guojun; Wang, Zaizhao

    2014-08-10

    Growth differentiation factor 9 (Gdf9) and bone morphogenetic protein 15 (Bmp15) are members of transforming growth factor β (TGFβ) superfamily that plays important roles in regulating ovarian functions. We cloned the cDNAs of gdf9 and bmp15 in rare minnow Gobiocypris rarus. The full length cDNAs of gdf9 and bmp15 were 1999 and 1721 bp, encoding 431 and 384 amino acids respectively. They both contained conserved TGFβ superfamily domain, with six conserved cysteine residues. Tissue distribution showed that both gdf9 and bmp15 are highly expressed in the G. rarus ovary. Following bisphenol A (BPA) treatment, ovarian transcripts of gdf9 and bmp15 together with the gonadosomatic index and the ovarian histology were altered. It suggests that the altered gdf9 and bmp15 expression may play roles in the weight gain and abnormal development of the ovary following BPA exposure.

  4. Responsiveness of four gender-specific genes, figla, foxl2, scp3 and sox9a to 17α-ethinylestradiol in adult rare minnow Gobiocypris rarus.

    PubMed

    Yuan, Cong; Wu, Tingting; Zhang, Yingying; Gao, Jiancao; Yang, Yanping; Qin, Fang; Liu, Shaozhen; Zheng, Yao; Wang, Zaizhao

    2014-05-01

    Proteins encoded by figla, foxl2, scp3 and sox9a play important roles in gonad differentiation and reproduction. In the present study, we aimed to determine the responsiveness of figla, foxl2, scp3 and sox9a to 17α-ethinylestradiol (EE2) in the gonads of adult Gobiocypris rarus. Full-length cDNAs of figla, scp3 and sox9a were cloned and characterized by RT-PCR and RACE methods. Expression patterns in adult tissues were investigated. Results indicated that figla was predominantly expressed in adult ovaries and scp3 was restrictively expressed in the male testes and sox9a was principally expressed in the brains of both genders and the testes of males. Gene expression profiles of figla, foxl2, scp3 and sox9a were analyzed in the gonads of adult G. rarus exposed to EE2 at 1, 5, 25, and 125ng/L for 3 and 6days. Three-day EE2 treatment at 1-125ng/L all caused a significant increase of figla transcript in testes and foxl2 transcript in ovaries. However, six-day EE2 exposure at 1-125ng/L repressed figla and scp3 transcript in testes and foxl2 transcript in ovaries. The present study indicates that the testicular transcripts of figla and scp3 in males and the ovarian foxl2 transcript in females have high responsiveness to EE2 and they can be used as sensitive molecular biomarkers for early warning to monitor the environmental estrogenic chemicals in fresh water environment. The present study also suggests that the effective EE2 dosage for feminization in male G. rarus might be at least 25ng/L. PMID:24631545

  5. Differential Toxicity and Accumulation of Fipronil Enantiomers in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Fipronil is a chiral insecticide applied as a racemate of two enantiomers. Because of its high log Koc, fipronil will be found primarily in sediments of aquatic environments. Although a number of studies have examined toxicity in aquatic invertebrates, data on enantioselective t...

  6. Development of a Computational Model for Female Fathead Minnows exposed to Two Endocrine Disrupting Chemicals

    EPA Science Inventory

    Endocrine disrupting chemicals (e.g., estrogens and androgens) are known to affect reproductive functions in fish. A synthetic estrogen used in birth control pills, 17á-ethynylestradiol (EE2), is discharged from wastewater treatment plants into water bodies throughout the United ...

  7. VITELLOGENIN GENE EXPRESSION IN FATHEAD MINNOWS EXPOSED TO EE2 IN A WHOLE LAKE DOSING EXPERIMENT

    EPA Science Inventory

    A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA), northwestern Ontario in 2001 and 2002. This experiment examined population, organism, biochemical and cellular-level effects in lake trout, white sucke...

  8. EVALUATION OF METHOXYCHLOR AS AN ENDOCRINE DISRUPTOR IN FATHEAD MINNOWS (PIMEPHALES PROMELAS).

    EPA Science Inventory

    Recent concern over the possible effects of endocrine-disrupting chemicals (EDCs) on humans and wildlife has resulted in considerable interest in environmental contaminants that adversely affect aspects of ...

  9. COMPARISON OF FATHEAD MINNOW AND HUMAN ESTROGEN RECEPTOR BINDING TO ENDOCRINE DISRUPTING COMPOUNDS

    EPA Science Inventory

    Environmental estrogens have the potential to disrupt endocrine function in a myriad of species. However, in vitro assays designed to detect and characterize endocrine disrupting chemicals (EDCs) typically utilize mammalian estrogen receptors. Our overall objective is to charac...

  10. A SHORT TERM REPRODUCTIVE ASSAY WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS). 1. METHOD DESCRIPTION

    EPA Science Inventory

    Due to the time and expense associated with full life-cycle testing, most current toxicology tests with fish do not explicity consider reproductive output as an endpoint but, rather, focus on early life-stage survival and development. However, some classes of chemicals could adve...

  11. A SHORT TERM REPRODUCTION TEST WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS): LL. METHOD EVALUATION

    EPA Science Inventory

    The U.S. Environmental Protection Agency is required to develop, validate, and implement a screening program for identifying potential endocrine-disrupting chemicals. The objective of this research was to evaluate the recommended short term test which assesses alterations in repr...

  12. A SHORT-TERM REPRODUCTIVE TEST WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Due to the time and expense associated with full life-cycle testing, most current toxicity tests with fish do not explicity consider reproductive output as an endpoint but, rather, focus on early life-stage survival and development. However, there are classes of chemicals that co...

  13. ASSESSING THE USE OF OLIGONUCLEOTIDE MICROARRAYS FOR FATHEAD MINNOW (PIMEPHALES PROMELAS) TO EXAMINE EXPOSURE VARIABLES

    EPA Science Inventory

    Microarray technology has proven to be a useful tool for analyzing the transcriptome of various organisms representing conditions such as disease states, developmental stages, and responses to chemical exposure. Although most commercially available arrays are limited to organism...

  14. A SHORT-TERM REPRODUCTION TEST WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS): L METHODS DESCRIPTION

    EPA Science Inventory

    Due to the time and expense associated with full life-cycle testing, most current toxicity tests with fish do not explicity consider reproductive output as an endpoint but, rather, focus on early life-stage survival and development. However, there are classes of chemicals that co...

  15. Effects of Gemfibrozil on Cholesterol Metabolism, Steroidogenesis, and Reproduction in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Fibrates are a class of pharmaceuticals that indirectly modulate cholesterol biosynthesis through effects on peroxisome proliferator-activated receptors, which are transcriptional cofactors that regulate expression of genes related to lipid metabolism. Gemfibrozil is a fibrate th...

  16. Genotyping Sex in Fathead Minnows, Pimephales promelas, for Use in Endocrine Disruption Assays

    EPA Science Inventory

    Endocrine disrupting compounds have been shown to completely sex reverse both male and female individuals in amphibian, avian, fish, invertebrate, and reptile species. In many cases these sex-reversed individuals are morphologically indistinguishable from normal individuals. De...

  17. Genotyping Sex in Fathead Minnows, Pimephales promelas, for Use in Endocrine Disruption Assays

    EPA Science Inventory

    Endocrine disrupting compounds have been shown to completely sex reverse both male and female individuals in amphibian, avian, fish, invertebrate, and reptile species. In many cases these sex-reversed individuals are morphologically indistinguishable from normal individuals. Dete...

  18. Environmental gestagens activate fathead minnow (Pimephales promelas) nuclear progesterone and androgen receptors in vitro

    EPA Science Inventory

    Gestagen is a collective term for endogenous and synthetic progesterone receptor (PR) ligands. In teleost fishes, 17á,20â-dihydroxy-4-pregnen-3-one (DHP) and17á,20â,21- trihydroxy-4-pregnen-3-one (20â-S) are the predominant progestogens, whereas in other vertebrates the major pro...

  19. Studies on the acute toxicity of fluoride ion to stickleback, fathead minnow, and rainbow trout

    SciTech Connect

    Smith, L.R.; Holsen, T.M.; Ibay, N.C.; Block, R.M.; De Leon, A.B.

    1985-01-01

    The authors have studied the acute toxicity of fluoride ion to Gasterosteus aculeatus, Fimephales promelas, and juvenile Salmo gairdneri. LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride levels in Salmo gairdneri.

  20. IDENTIFICATION OF ENDOCRINE DISRUPTORS USING A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW

    EPA Science Inventory

    Tests with small fish have been a recommended of virtually every proposed regulatory program for endocrine-disrupting chemicals (EDCs). An ideal test would provide information suitable for determination of whether a chemical has the potential to exert adverse effects via specific...

  1. Hypothesis testing with computational modeling: linking aromatase inhibition with plasma vitellogenin dynamics in fathead minnows

    EPA Science Inventory

    Fadrozole inhibits aromatase (CYP19A), a key enzyme that converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis ofthe glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Whe...

  2. METALLOTHIONEIN GENE TRANSCRIPTION AS AN INDICATOR OF METAL EXPOSURE IN FATHEAD MINNOWS

    EPA Science Inventory

    Metallothionein is a cysteine rich, low molecular weight, metal binding protein. Basal levels of endogenous metallothioneins (MT) have been reported in all eucaryotes. MT has been shown to play an essential role in regulating physiological requirements of essential metals such a...

  3. Developmental Effects Of A Municipal Wastewater Effluent On Two Generations Of The Fathead Minnow, Pimephales promelas

    EPA Science Inventory

    Municipal wastewater effluents have been shown to contain a variety of anthropogenic compounds, many of which are know to display estrogenic properties. While multiple laboratory studies have shown the effects of such compounds on an individual basis at elevated concentrations, ...

  4. EFFECTS OF THE MAMMALIAN ANTIANDROGEN VINCLOZOLIN ON DEVELOPMENT AND REPRODUCTION OF THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Previous work with the chlorinated fungicide vinclozolin and its metabolites, 2-{[(3,5-dichloropheny1]-carbamoyl]oxy}-2-methyl-3-butenoic acid (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2), indicated antiandrogenic properties expressed in vivo as abnormalities in...

  5. EFFECTS OF THE MAMMALIAN ANTIANDROGEN VINCLOZOLIN ON DEVELOPMENT AND REPRODUCTION OF THE FATHEAD MINNOW

    EPA Science Inventory

    Previous work with the chlorinated fungicide vinclozolin and its metabolites, 2-{[(3,5-dichlorophenyl)-carbamoyl]oxy}-2-methyl-3-butenoic acid (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2), indicated antiandrogenic properties expressed in vivo as abnormalities in...

  6. Evaluation of arsenic speciation in rainbow trout and fathead minnows from dietary exposure

    EPA Science Inventory

    The concentration of total arsenic and various arsenic species were measured in food and fish tissue samples from two dietary arsenic exposures to juvenile fish. For arsenic speciation, samples were extracted with 10% MeOH and analyzed by HPLC/ICPMS. Total arsenic concentration...

  7. VITELLOGENIN GENE EXPRESSION IN MALE FATHEAD MINNOWS EXPOSED TO DI(2-ETHYLHEXYL)PHTHALATE

    EPA Science Inventory

    Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer used extensively in the plastics industry. DEHP has been shown to be ubiquitous in the environment and has been detected in ground and surface waters, sediment sludge and at several Superfund sites. Previous studies using rats ...

  8. Effects of the Antipsychotic Drug, Haloperidol, on Reproduction in the Fathead Minnow

    EPA Science Inventory

    Haloperidol is a butyrophenone antipsychotic drug used for the treatment of human hyperactive and manic disorders, agitation, and schizophrenia. The drug is thought to act through antagonism of dopaminergic receptors. We have studied a variety of endocrine-disrupting chemicals wi...

  9. Effects of Diethylstilbestrol in Fathead Minnows: Part 2. Concentrations in Water and Tissues

    EPA Science Inventory

    Diethylstilbestrol (DES), a synthetic nonsteroidal estrogen, was once widely prescribed to prevent miscarriages, and was used as a growth promoter in feed for beef and poultry production. After it was determined that DES caused significant adverse effects in the offspring of mot...

  10. Effects of the insecticide fipronil on reproductive endocrinology in the fathead minnow

    EPA Science Inventory

    Gamma aminobutyric acid (GABA) and GABA receptors play an important role in neuroendocrine regulation in fish. Disruption of the GABAergic system by environmental contaminants could interfere with normal regulation of the hypothalamic pituitary gonadal (HPG) axis, leading to imp...

  11. Effects of a Glucocorticoid Receptor Agonist, Dexamethasone, on Fathead Minnow Reproduction and Development

    EPA Science Inventory

    Few studies have examined the effects of synthetic glucocorticoids on the reproductive axis of fish, despite the fact that these chemicals are therapeutically prescribed anti-inflammatory agents that are abundantly produced and consumed. To generate data to assess potential risk ...

  12. Effects of a Glucocorticoid Receptor Agonist, Dexamethasone, on Fathead Minnow Reproduction, Growth, and Development.

    EPA Science Inventory

    Few studies have examined the effects of synthetic glucocorticoids on the reproductive axis of fish, despite the fact that these chemicals are therapeutically prescribed anti-inflammatory agents that are abundantly produced and consumed. To generate data to assess potential risk ...

  13. Enantioselective toxicity and bioaccumulation of fipronil in fathead minnows (Pimephales promelas) following water and sediment exposures

    EPA Science Inventory

    Fipronil is a widely used, broad-spectrum pesticide that is applied as an equal mixture of two enantiomers. As regulations on older pesticides become more stringent, production and application of fipronil is expected to grow, leading to increased inputs into aquatic environments ...

  14. Effects of gemfibrozil on lipid metabolism, steroidogenesis and reproduction in the fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Fibrates are a class of pharmaceuticals that indirectly modulate cholesterol biosynthesis through effects on peroxisome proliferator-activated receptors (PPARs), which are transcriptional cofactors that regulate expression of genes related to lipid metabolism. Gemfibrozil is a fi...

  15. Perturbation of Gene Expression and Steroidogenesis with In vitro Exposure of Fathead Minnow Ovaries to Ketoconazole

    EPA Science Inventory

    Various chemicals in the environment can disrupt normal endocrine function, including steroid hormone synthesis, causing deleterious effects. Because these compounds can act at different levels of the hypothalamus-pituitary-gonadal (HPG) axis, their effects can lead to a mixture...

  16. A Compendium of Transcriptomic Effects of Endocrine Disrupting Chemicals on the Fathead Minnow Ovary

    EPA Science Inventory

    Understanding potential hazards of chemicals released into the environment is challenging not only due to the large and growing number of chemicals and materials that need to be screened, but also to the bioavailability, exposure conditions, and species differences among others. ...

  17. Cloning and initial characterization of nuclear and membrane progesterone receptors in the Fathead Minnow, Pimephales promelas

    EPA Science Inventory

    Both native progestagens and synthetic progestins have important effects on reproduction that are mediated through progesterone receptors (PRs). They regulate gamete maturation and can serve as precursors for other steroid hormones in vertebrates and act as reproductive pheromone...

  18. FATHEAD MINNOW AND PEARL DACE PILOT AT CANADIAN EXPERIMENTAL LAKES AREA

    EPA Science Inventory

    There is increasing concern about the potential impact of EDCs on aquatic organisms. Among the EDCs found in aquatic habitats are synthetic estrogens, which are used in contraceptives and other pharmaceuticals. These chemicals enter waterways through sewage treatment plants and s...

  19. Dynamic Nature of Alterations in the Endocrine System of Fathead Minnows Exposed to Prochloraz

    EPA Science Inventory

    The vertebrate hypothalamic-pituitary-gonadal (HPG) axis is controlled through various feedback mechanisms, ideally maintaining dynamic homeostasis in the face of changing environmental conditions, including exposure to chemical stressors. These studies assessed the effects of t...

  20. Investigation of adaptive responses in fathead minnows (Pimephales promelas) exposed to the model aromatase inhibitor fadrozole

    EPA Science Inventory

    The vertebrate hypothalamic-pituitary-gonadal (HPG) axis is a highly dynamic system, which, through various feedback mechanisms, strives to maintain physiological conditions conducive to reproduction even in potentially stressful situations. The development of useful predictive m...

  1. Effects of Gemfibrozil on Cholesterol Metabolism and Steroidogenesis in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Fibrates are a class of pharmaceuticals that indirectly modulate cholesterol biosynthesis through effects on peroxisome proliferator-activated receptors (PPAR), which are transcriptional cofactors that regulate expression of genes related to lipid metabolism. Gemfibrozil is a fib...

  2. Effects of Gemfibrozil on Cholesterol Metabolism, Steroidogenesis, and Reproduction in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Fibrates are a class of pharmaceuticals that indirectly modulate cholesterol biosynthesis through effects on peroxisome proliferator-activated receptors (PPAR), which are transcriptional cofactors that regulate expression of genes related to lipid metabolism. Gemfibrozil is a fib...

  3. Effects of Diethylstilbestrol in Fathead Minnows: Part 1. Effects on Reproductive Endocrine Function

    EPA Science Inventory

    Diethylstilbestrol (DES), a synthetic nonsteroidal estrogen, was once widely prescribed to prevent miscarriages, and was used as a growth promoter in feed for beef and poultry production. After it was determined that DES caused significant adverse effects in the offspring of mo...

  4. Method optimization for fathead minnow (Pimephales promelas) liver S9 isolation

    EPA Science Inventory

    Standard protocols have been proposed to assess metabolic stability in rainbow trout liver S9 fractions. Using in vitro substrate depletion assays, in vitro intrinsic clearance rates can be calculated for a variety of study compounds. Existing protocols suggest potential adaptati...

  5. DIFFERENTIAL DISPLAY OF TRENBOLONE AND DEHP INDUCED GENE TRANSCRIPT PATTERNS IN FATHEAD MINNOW LIVER

    EPA Science Inventory

    The endocrine disruptor risk assessment process is being delayed without more robust data on the estrogenic and androgenic activity of chemicals found in the environment such as trenbolone and di(2-ethylhexyl) phthalate (DEHP). Trenbolone is an androgenic compound known to reduc...

  6. EVALUATION OF EFFECTS OF THE SYNTHETIC ANDROGEN METHYLTESTOSTERONE ON REPRODUCTION IN THE FATHEAD MINNOW

    EPA Science Inventory

    Various studies have assessed the effects of estrogenic xenobiotics on reproduction and related endpoints in fish. Comparatively less research has been done with chemicals that elicit toxicity through alterations in androgen-mediated processes. The purpose of this study was to ev...

  7. Sensitivity of the vitellogenin assay to diagnose exposure of fathead minnows to 17α-ethynylestradiol

    EPA Science Inventory

    Vitellogenin is frequently used as a biomarker of exposure to environmental estrogens. When designing an experiment using vitellogenin, investigators must decide whether to deploy fish in the field or expose fish in the lab, how many fish to expose, and how long to expose the fi...

  8. Effects of Environmentally Relevant Concentrations of Bisphenol A on the Fathead Minnow

    EPA Science Inventory

    Bisphenol A (BPA) is a wide-spread environmental contaminant of concern due, in part, to possible effects on the vertebrate hypothalamic-pituitary-gonadal (HPG) axis, including activation of the estrogen receptor (ER). There is a reasonable amount of toxicological information fo...

  9. Effects of Xenoestrogen and Androgen Mixtures on Ovarian Transcriptome of the Fathead Minnow

    EPA Science Inventory

    Endocrine disrupting chemicals (EDCs), such as the estrogens ethinylestradiol (EE2) and bisphenol A (BPA), and androgens like 17â-trenbolone (TRB) can occur as mixtures in aquatic environments. To date, however, most studies with EDCs in fish have focused on their effects as indi...

  10. Hormone Binding to Recombinant Estrogen Receptors from Human, Alligator, Quail, Salamander, and Fathead Minnow

    EPA Science Inventory

    In this work, a 96-well plate estrogen receptor binding assay was developed to facilitate the direct comparison of chemical binding to full-length recombinant estrogen receptors across vertebrate classes. Receptors were generated in a baculovirus expression system. This approach ...

  11. Integrated approach to explore the mechanisms of aromatase inhibition and recovery in fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Aromatase, a member of the cytochrome P450 superfamily, is a key enzyme in estradiol synthesis that catalyzes the aromatization of androgens into estrogens in ovaries. Here, we used an integrated approach to assess the mechanistic basis of the direct effects of aromatase inhibiti...

  12. VITELLOGENIN GENE TRANSCRIPTION AS AN INDICATOR OF EXPOSURE TO 17-ALPHA-ETHYNYLESTRADIOL IN FATHEAD MINNOWS

    EPA Science Inventory

    Environmentally persistent chemicals that functionally mimic estrogen are ubiquitous in surface waters and have been shown to effect reproductive health of species living in these habitats. Toxicant induced transcription of specific genes is a sensitive indicator of exposure and ...

  13. A Computational Model for Oocyte Growth Dynamics in Fathead Minnows (Pimephales promelas)

    EPA Science Inventory

    Molecular biomarkers have been used in ecotoxicological studies to evaluate the effects of endocrine disrupting chemicals in fish. Ideally, changes in these molecular biomarkers should be linked to the effects upon reproduction in individuals, and subsequently populations. To m...

  14. Development and Validation of a 2,000 Gene Microarray in the Fathead Minnow, Pimephales promelas

    EPA Science Inventory

    The development of the gene microarray has given the field of ecotoxicology a new tool to understand the mechanisms of action (MOA) of various anthropogenic compounds. . .Overall, data from this analysis suggest that the microarrays can be broadly useful in ecotoxicology studies ...

  15. Determining the effects of ammonia on fathead minnow (Pimephales promelas) reproduction

    EPA Science Inventory

    Aquatic organisms are exposed to a multitude of contaminants and to fully understand the impact of multiple stressors on fish populations, we should first understand the mechanism of action for each toxicant and how the combined effects manifest at the level of the individual. Am...

  16. EVALUATION OF FADROZOLE AS AN ENDOCRINE DISRUPTOR IN FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    The EPA has received a legislative mandate to develop and implement standardized screening and testing methods to identify and assess potential endocrine disrupting chemicals (EDCs). The objective of this research was to evaluate a short-term EDC screening/testing assay which ass...

  17. THE INSTABILITY OF ESTROGENIC CHEMICALS DURING LABORATORY STATIC EXPOSURE CONDITIONS WITH MALE FATHEAD MINNOWS

    EPA Science Inventory

    Endocrine disrupting chemicals (EDCs) such as Para-nonylphenol (NP), estradiol (E2), estrone (E1), estriol (E3) and ethynylestradiol (EE2) are shown to be ubiquitous in surface waters, sediments and sludge. These EDCs are known to induce vitellogenin gene (Vg) expression in male...

  18. Comparative Biological Effects and Potency of 17a- and 17ß-Estradiol In Fathead Minnows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    17ß-estradiol is the most potent natural estrogen commonly found in anthropogenically altered environments and has been the focus of many toxicological laboratory studies. However, fewer aquatic toxicological data on the effects of 17a-estradiol, a diastereoisomer of 17ß-estradiol, exists in the li...

  19. Survival of copper-exposed juvenile fathead minnows (Pimephales promelas) differs among allozyme genotypes

    SciTech Connect

    Schlueter, M.A.; Guttman, S.I.; Oris, J.T.; Bailer, A.J.

    1995-10-01

    The effects of seven variable enzyme loci and multiple-locus heterozygosity on time to death (TTD) during an acute 96-h copper exposure were examined by two failure-time regression models. Allozymes for five enzyme loci (GPI-1*, GPI-2*, IDHP-1*, MDH-2*, and PGM*) were significantly related to TTD. Heterozygosity was not significantly related to TTD. Fish weight was found to have a negative relationship with TTD, larger fish having shorter TTD. This unusual relationship may have resulted from differential survivorship of individuals with sensitive and resistant alleles at the MDH-2* and the IDHP-1* loci. For the IDHP-1* locus the allele *a at the MDH-2* locus, which was present in higher frequency in larger fish, was associated with decreased survivorship. These results indicate that genetic selection for one characteristic may have a negative impact on other characteristics. Survivors of the copper exposure were genetically selected for copper resistance, resulting in the significant reduction in frequencies of several sensitive genotypes in the population. The authors conclude that monitoring population genetic structure and frequency changes of sensitive genotypes is a useful biomarket.

  20. Allozyme genotype and survival of juvenile fathead minnows, Pimephales promelas, exposed to copper

    SciTech Connect

    Schlueter, M.A.; Guttman, S.I.; Oris, J.T.; Bailer, A.J.

    1994-12-31

    Populations inhabiting contaminated areas have been Found to exhibit genetically based tolerance. Tolerance to a contaminant can only develop when appropriate genetic diversity exist in the stressed population. The effects of seven variable enzyme loci and multiple-locus heterozygosity on time to death (TTD) during an acute copper exposure were examined by creating two failure time regression models. Allozymes for five enzyme loci (Gpi-1, Gpi-2, ldh-1, Mdh-2, and Pgm) were significantly related to TTD. The model identified several resistant and sensitive allozyme genotypes. Heterozygosity was not related to TTD. Genetic diversity may be developed into a useful biomarker by monitoring frequency changes of sensitive genotypes.

  1. Gene Expression Responses in Male Fathead Minnows Exposed to Binary Mixtures of an Estrogen and Antiestrogen

    EPA Science Inventory

    Aquatic organisms are continuously exposed to complex mixtures of chemicals, many of which can interfere with their endocrine system, resulting in impaired reproduction, development or survival, among others. In order to analyze the effects and mechanisms of action of estrogen...

  2. Enantioselective Toxicity and Biotransformation of Fipronil in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Fipronil is a relatively new chiral phenylpyrazole insecticide used to control both agricultural and household invertebrate pests. Fipronil is applied as a racemate, or equal mixture, of its two enantiomers. As regulations on older pesticides increase, production and applicatio...

  3. EVALUATION OF METHOXYCHLOR AS AN ENDOCRINE DISRUPTOR IN FATHEAD MINNOWS (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Recent concerns over the possible effects of endocrine-disrupting chemicals (EDCs) on humans and wildlife has resulted in considerable interest in environmental contaminants that adversely affect aspects of sexual reproduction and early development. The U.S. Environmental Protect...

  4. Effects of the azole fungicide imazalil on the fathead minnow (Pimephales promelas) steroidogenesis pathway

    EPA Science Inventory

    Azole fungicides, used for both agriculture and human therapeutic applications may disrupt endocrine function of aquatic life. Azole fungicides are designed to inhibit the fungal enzyme lanosterol 14 á-demethylase (cytochrome P450 [CYP] 51). However, they can also interact...

  5. Expression Signatures for a Model Androgen and Antiandrogen in the Fathead Minnow Pimephales promelas Ovary

    EPA Science Inventory

    Trenbolone and flutamide are prototypical model compounds for respectively androgen and antiandrogen modes of action. Trenbolone is an anabolic steroid used in cattle industry to increase weight gain and feed efficiency, and flutamide is a pharmaceutical used to treat prostate c...

  6. Non-gel Based Proteomics to Study Steroid Receptor Agonists in the Fathead Minnow

    EPA Science Inventory

    Toxicoproteomics is an emerging field that is greatly enabled by non-gel based methods using LC MS/MS for biomarker discovery and characterization for endocrine disrupting chemicals. Using iTRAQ (isobaric tagging for relative and absolute quantitation), we quantified a diverse r...

  7. Quantitative Proteomic Profiles of Androgen Receptor Signaling in the Liver of Fathead Minnows Pimephalus promelas

    EPA Science Inventory

    Androgenic chemicals are present in the environment at concentrations that impair reproductive processes in fish. The objective of this experiment was to identify proteins altered by an androgen receptor agonist (17â-trenbolone) and antagonist (flutamide) in the liver. Female fa...

  8. Testing quantitative adverse outcome pathway predictions using aromatase inhibitors in female fathead minnows

    EPA Science Inventory

    To become more efficient and cost effective regulatory toxicology is increasingly averting from whole animal testing toward collecting data at lower levels of biological organization, through such means as in vitro high throughput screening (HTS) assays. When anchored to relevant...

  9. The Effects of Endocrine Disruptors on Steroidogenesis Gene Expression Dynamics in Fathead Minnow

    EPA Science Inventory

    Steroid hormones play key roles in regulating reproduction and development and fish and other vertebrates. This presentation reports results from two in vitro experiments aimed characterizing the dynamics of transcriptional and metabolomic responses to endocrine disrupting chemi...

  10. Bisphenol A induces spermatocyte apoptosis in rare minnow Gobiocypris rarus.

    PubMed

    Zhang, Yingying; Cheng, Mengqian; Wu, Lang; Zhang, Guo; Wang, Zaizhao

    2016-10-01

    Bisphenol A (BPA) is an endocrine disruptor, and could induce germ cells apoptosis in the testis of mammals. But whether it could affect fish in the same mechanism has not' been studied till now. In the present study, to investigate the influence of BPA on testis germ cells in fish, adult male rare minnow Gobiocypris rarus were exposed to 225μgL(-1) (0.99μM) BPA for 1, 3 and 9 weeks. Through TdT-mediated dUTP nick end labeling (TUNEL) and transmission electron microscope (TEM) analysis, we found that the amount of apoptotic spermatocytes significantly increased in a time dependent manner following BPA exposure. Western Blot results showed that the ratio of Bcl2/Bax, the important apoptosis regulators in intrinsic mitochondrial apoptotic pathway, was significantly decreased. qPCR showed that mRNA expression of several genes in mitochondrial apoptotic pathway including bcl2, bax, casp9, cytc and mcl1b were significantly changed following BPA exposure. In addition, mRNA expression of meiosis regulation genes (kpna7 and wee2), and genes involved in both apoptosis and meiosis (birc5, ccna1, and gsa1a) were also affected by BPA. Taken together, the present study demonstrated that BPA could induce spermatocytes apoptosis in rare minnow testis, and the apoptosis was probably under regulation of intrinsic mitochondrial apoptotic pathway. Moreover, the spermatocyte apoptosis was likely initiated by BPA induced meiosis arrest. PMID:27561114

  11. PLASMA CLEARANCE OF VITELLOGENIN IN SHEEPSHEAD MINNOWS AFTER CESSATION OF EXPOSURE TO 17BETA-ESTRADIOL AND PARA-NONYLPHENOL

    EPA Science Inventory

    Two experiments were performed to determine the rate of vitellogenin plasma accumulation and clearance in male sheepshead minnows (Cyprinodon variegatus) during and after exposure to either 17b-estradiol (E2) or para-nonylphenol (p-NP). Adult fish were continuously exposed to aqu...

  12. Personnel observe minnows to be sent aboard Skylab 3

    NASA Technical Reports Server (NTRS)

    1973-01-01

    John Boyd observes a bag with two 'brackish water' minnows known as 'Mummichog Minnows' which will be on board Skylab 3. The fish were added to the flight at the request of Scientist-Astronaut Dr. Owen K. Garriott, science pilot. The objective of this experiment is to show what disorientation the fish will experience when exposed to weightlessness. An aquarium of the Minnows, caught off the coast of Beaufort, North Carolina, is in the background.

  13. TEMPORAL AND SPATIAL VARIABILITY IN THE ESTROGENICITY OF A MUNICIPAL WASTEWATER EFFLUENT

    EPA Science Inventory

    Estrogenicity of a municipal wastewater effluent was monitored using the vitellogenin biomarker in adult male fathead minnows (Pimephales promelas). Variability in expression of the vitellogenin biomarker was evident among monitoring periods. Significant increases in plasma vit...

  14. Use of Microarray to Analyze Gene Expression Profiles of Acute Effects of Prochloraz on Fathead Minnows Pimephales promelas

    EPA Science Inventory

    Microarray technology is a powerful tool to investigate the gene expression profiles for thousands of genes simultaneously. In recent years, microarrays have been used to characterize environmental pollutants and identify molecular mode(s) of action of chemicals including endocri...

  15. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists, including those recommended for use in the EPA's Tier 1 screening battery, typically use mammalian estrogen (ER) and androgen receptors (AR) such as rat or human. Although we know that the amino acid s...

  16. Effects of a real-time exposure to an estrogenic effluent on reproduction in the fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Wastewater treatment plant (WWTP) effluents are a well-established point of convergence through which anthropogenic chemicals enter surface waters. Whole effluent testing guidelines were developed to screen these complex mixtures for acute toxicity. However, effects-based approac...

  17. Effects of Fadrozole, Ketoconazole, and 17β-trenbolone on Ex Vivo Steroidogenesis in the Fathead Minnow

    EPA Science Inventory

    A variety of endocrine-disrupting chemicals have the ability to disrupt steroidogenesis through interaction with the hypothalamic-pituitary-gonadal (HPG) axis. We examined the effects of the competitive aromatase inhibitor fadrozole (0, 3, and 30 g/L), the cytochrome P450 enzyme...

  18. The effects of resistant and sensitive alleles on survivorship, weight, and heterozygosity in the fathead minnow, Pimephales promelas

    SciTech Connect

    Schlueter, M.; Guftman, S.

    1995-12-31

    In three separate acute copper exposures a highly significant (p = 0.0001) negative relationship was detected between fish weight and survivorship. Overall heterozygosity was not related to survivorship. The effects of two single loci IDHP 1* and MDH-2* were shown to be partially responsible for these results. For the IDHP-1* locus allele *a was associated with increased copper survivorship; however, it was also associated with small size. Conversely, the allele *a at the MDH-2* locus, which was present in higher frequencies in larger fish, was associated with decreased survivorship. If the genotype at an individual locus strongly affects survivorship, being a homozygote at that locus may be more significant to survivorship than overall individual heterozygosity. These results suggest that genetic selection for one characteristic may have a negative impact on other characteristics. These results may help explain unusual relationships between weight and other characteristics and survivorship found in other studies.

  19. Linkage of Biochemical Responses to Population-level Effects: A Case Study with Vitellogenin in the Fathead Minnow (Pimephales promelas).

    EPA Science Inventory

    We present a novel approach to quantifying estuarine habitat use by fish using stable isotopes. In brief, we further developed and evaluated an existing stable isotope turnover model to estimate the time American shad, an anadromous clupeid, spend in various river habitats durin...

  20. Integrated ecological hazard assessment of waste site soil extracts using FETAX and short-term fathead minnow teratogenesis assay

    SciTech Connect

    Fort, D.J.; Stover, E.L.; Bantle, J.A.

    1996-12-31

    Frog Embryo Teratogenesis Assay-Xenopus (FETAX) is a 96-h whole embryo-larval assay designed to detect environmental developmental toxicants for use in ecological hazard assessment. FETAX offers several advantages in integrated biological hazard assessment including, time- and cost-effectiveness, technical ease, and versatility. FETAX has undergone extensive intra- and more recently interlaboratory validation with known mammalian teratogens and non-teratogens. Ecological hazard evaluations of contaminated sediments, waste site soils, and complex surface and groundwaters have also been performed. An integrated hazard assessment study using FETAX, the conventional, Pimephales promelas 7-d teratogenecity test, and an abbreviated P. promelas teratogenecity test utilizing the general FETAX protocol was conducted with specific reference toxicants and aqueous extracts of contaminated hazardous waste site soils. Results from the studies indicated that FETAX can be used as a component of a battery of bioassays designed to assess potential ecological hazard. Furthermore, the generalized FETAX protocol may be useful with other species in evaluating developmental toxicity hazard.

  1. Pathway level impacts of in situ exposure of fathead minnow to effluent mixtures in the Duluth harbor

    EPA Science Inventory

    There is a major effort to characterize the potential adverse effects of effluents released from sewage treatment plants in North America. At many locations pharmaceuticals, endocrine disruptors, and other chemicals of emerging concerns are present in the environment at concentra...

  2. Crafting a gene expression timeline for the thyroid in the early-life stages of fathead minnows (Pimephales promelas)

    EPA Science Inventory

    The hypothalamic-pituitary-thyroid (HPT) axis plays a number of critical roles in chordate physiology including regulation of metabolism, growth, and development. While the role of the HPT axis and thyroid hormone signaling in mammalian and amphibian development is well establis...

  3. Impaired anterior swim bladder inflation following exposure to the thyroid peroxidase inhibitor 2-Mercaptobenzothiazole Part I: Fathead minnow

    EPA Science Inventory

    Development of adverse outcome pathways linking specific chemical-induced pathway perturbations to adverse outcomes relevant to regulatory decision-making has potential to support the development of alternatives to traditional whole organism toxicity tests, such as the fish early...

  4. Evidence for Compensatory Responses at the Molecular, Biochemical, and Tissue Level in Fathead Minnows Exposed to Steroidogenesis Inhibitors

    EPA Science Inventory

    In order to survive, organisms require a capacity to adapt to a wide variety of biotic and abiotic stressors, including chemicals of both natural and synthetic origin. Recent studies in our laboratory have provided evidence of compensatory responses to endocrine active chemicals...

  5. Cloning and initial characterization of nuclear and four membrane progesterone receptors in the fathead minnow(Pimephales promelas)

    EPA Science Inventory

    Both native progestagens and synthetic progestins have important effects on reproduction that are mediated through progesterone receptors (PRs). Progestagens regulate gamete maturation in vertebrates, are critical regulators of placental mammal pregnancy, and act as reproductive ...

  6. Statistically validated QSARs, based on theoretical descriptors, for modeling aquatic toxicity of organic chemicals in Pimephales promelas (fathead minnow).

    PubMed

    Papa, Ester; Villa, Fulvio; Gramatica, Paola

    2005-01-01

    The use of Quantitative Structure-Activity Relationships in assessing the potential negative effects of chemicals plays an important role in ecotoxicology. (LC50)(96h) in Pimephales promelas (Duluth database) is widely modeled as an aquatic toxicity end-point. The object of this study was to compare different molecular descriptors in the development of new statistically validated QSAR models to predict the aquatic toxicity of chemicals classified according to their MOA and in a unique general model. The applied multiple linear regression approach (ordinary least squares) is based on theoretical molecular descriptor variety (1D, 2D, and 3D, from DRAGON package, and some calculated logP). The best combination of modeling descriptors was selected by the Genetic Algorithm-Variable Subset Selection procedure. The robustness and the predictive performance of the proposed models was verified using both internal (cross-validation by LOO, bootstrap, Y-scrambling) and external statistical validations (by splitting the original data set into training and validation sets by Kohonen-artificial neural networks (K-ANN)). The model applicability domain (AD) was checked by the leverage approach to verify prediction reliability.

  7. Dynamic Nature of Alterations in the Endocrine System of Fathead Minnows Exposed to the Fungicide Prochloraz, Presentation

    EPA Science Inventory

    The vertebrate hypothalamic-pituitary-gonadal (HPG) axis is controlled through various feedback mechanisms that ideally serve to maintain a dynamic homeostasis of the system in the face of changing environmental conditions, including exposure to chemical stressors. In these stud...

  8. Short-term effects of propiconazole on hypothalamic-pituitary-gonadal function in the fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Propiconazole is an ergosterol inhibitor commonly used in agriculture and has been detected in aquatic environments. Ergosterol inhibitors decrease fungal growth through effects on 14á-demethylase, a cytochrome P450 (CYP), isoform important for ergosterol biosynthesis. In higher ...

  9. Unsupervised Analysis of the Effects of a Wastewater Treatment Plant Effluent on the Fathead Minnow Ovarian Transcriptome

    EPA Science Inventory

    Wastewater treatment plant (WWTP) effluents contain complex mixtures of chemicals, potentially including endocrine active chemicals (EACs), pharmaceuticals, and other contaminants of emerging concern (CECs). Due to the complex and variable nature of effluents, biological monitori...

  10. Sex Differentiation as a Target of Endocrine Disrupting Compounds in Early Life Stage Fathead Minnows (Pimephales promelas)

    EPA Science Inventory

    The occurrence of endocrine disrupting chemicals (EDCs) in concentrated animal feed operation (CAFO) waste, and the potential effects of these chemicals on aquatic ecosystems have been of recent concern. There is evidence that exposure to EDCs during enhanced windows of sensitiv...

  11. Impacts of WWTP Effluents on the Hepatic Metabolome of Male and Female Fathead Minnows in the South Platte River, Colorado

    EPA Science Inventory

    Metabolomics is rapidly becoming established as an eefective tool for studying the responses of organisms, such as fish, to various environmentally relevant stressors. While the majority of the work has been laboratory-based, successful application of the technique in recent year...

  12. EFFECTS OF THE ANDROGENIC GROWTH PROMOTER 17-β TRENBOLONE ON FECUNDITY AND REPRODUCTIVE ENDROCRINOLOGY OF THE FATHEAD MINNOW

    EPA Science Inventory

    Trenbolone acetate is a synthetic steroid which is extensively used in the U.S. as a growth promoter in beef cattle. The acetate is administered to livestock via slow release implants; some is converted by the animal to 17-β trenbolone, a relatively potent androgen receptor ...

  13. Current lineages of the epithelioma papulosum cyprini (EPC) cell line are contaminated with fathead minnow, Pimephales promelas, cells

    USGS Publications Warehouse

    Winton, J.; Batts, W.; deKinkelin, P.; LeBerre, M.; Bremont, M.; Fijan, N.

    2010-01-01

    Initially established from proliferative skin lesions of the common carp, Cyprinus carpio L., the epithelioma papulosum cyprini (EPC) cell line (Fijan, Sulimanovic, Bearzotti, Muzinic, Zwillenberg, Chilmonczyk, Vautherot & de Kinkelin 1983) has become one of the most widely used tools for research on fish viruses and the diagnosis of fish viral diseases.

  14. Evaluation of the Antimicrobial Triclocarban in a Short-term Reproduction Assay with the Fathead Minnow Pimephales promelas

    EPA Science Inventory

    Triclocarban, commercially known as TCC, is a trichlorinated pesticide used extensively as an antimicrobial additive in personal care products. TCC is characterized as a high production volume chemical and recent monitoring programs have shown it is prevalent in aquatic environme...

  15. Effects of Cholesterol-altering Pharmaceuticals on Cholesterol Metabolism, Steroidogenesis, and Gene Expression in the Fathead Minnow (Pimephales promelas)

    EPA Science Inventory

    Pharmaceuticals that target cholesterol biosynthesis and uptake are among the most widely prescribed drugs and have been detected in the aquatic environment. Fibrates are a class of pharmaceuticals that indirectly modulate cholesterol biosynthesis through effects on peroxisome pr...

  16. COMPARATIVE EVALUATION OF ELISAS FOR DETECTING VITELLOGENIN IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)- A RESPONSE TO TYLER ET AL

    EPA Science Inventory

    Measurement of vitellogenin (VTG) in fish is rapidly moving from being an endpoint of concern mostly to reproductive physiology/endocrinology, to an endpoint on which international regulatory decision-making could well be based. Changes in VTG are of particular utility for the id...

  17. Effects of the anti-microbial, triclocarban, on the reproductive function and ovarian transcriptome of the fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Triclocarban (TCC) is a widely used antimicrobial agent that is routinely detected in surface waters. The present study was designed to examine TCC’s efficacy and mode of action as a reproductive toxicant in fish. Reproductively mature Pimephales promelas were continuously ...

  18. Comparing biological effects and potencies of estrone and 17 B-estradiol in mature fathead minnows, Pimephales promelas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of endocrine active compounds such as estrogens in treated wastewater effluent and their effects on aquatic life are causing concern among aquatic resource managers. In contrast to 17B-estradiol (E2), the steroid hormone produced by all vertebrates, the biological effects of estrone (E1...

  19. Comparing biological effects of estrone (E1) and 17ß-estradiol (E2) in mature fathead minnows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of endocrine active compounds such as estrogens in treated wastewater effluent and their effects on aquatic life are causing concern among aquatic resource managers. Among the natural estrogens are 17ß-estradiol, 17a-estradiol, and estrone. Although 17ß-estradiol has received significa...

  20. MOLECULAR, PROTEIN AND HISTOLOGICAL INDICATORS IN FATHEAD MINNOWS EXPOSEDF TO EE2 IN A WHOLE-LAKE DOSING EXPERIMENT

    EPA Science Inventory

    A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA), northwestern Ontario from 2001 to 2003. This experiment examined population, organism, biochemical and cellular-level effects in lake trout, white suck...

  1. Effects of a model 3B-hydroxysteroid Dehydrogenas Inhibitor, Trilostane, on Reproductive Endocrine Function in the Fathead Minnow

    EPA Science Inventory

    Inhibition of enzymes involved in the synthesis of sex steroids can substantially impact developmental and reproductive processes controlled by the hypothalmic-pituitary-gonadal (HPG) axis. A key steroidogenic enzyme that has received little attention from a toxicological perspec...

  2. Modeling a molecular initiating event to population effects: A case study of aromatase inhibition in fathead minnows

    EPA Science Inventory

    An adverse outcome pathway (AOP) conceptually links a molecular initiating event with measureable key events at higher levels of biological organization that ultimately result in an adverse outcome. Development of an AOP requires experimental data and scientific expertise to ide...

  3. Temporal Evaluation of Effects of a Model 3B-Hydroxysteroid Dehydrogenase Inhibitor on Endocrine Function in the Fathead Minnow

    EPA Science Inventory

    Inhibition of enzymes involved in the synthesis of sex steroids can substantially impact developmental and reproductive processes controlled by the hypothalmic-pituitary-gonadal (HPG) axis. A key steroidogenic enzyme that has received little attention from a toxicological perspe...

  4. A short-term study investigating the estrogenic potency of diethylstilbesterol in the fathead minnow (Pimephales promelas)

    EPA Science Inventory

    Diethylstilbestrol (DES) is a synthetic estrogen that has been banned for use in humans, but still is employed in livestock and aquaculture operations in some parts of the world. Detectable concentrations of DES in effluent and surface waters have been reported to range from slig...

  5. Identification of Androgen Receptor Antagonists in Fish Using a Simple Bioassay with the Fathead Minnow Pimephales promelas .

    EPA Science Inventory

    Considerable effort has been expended on the development of bioassays to detect chemicals that affect endocrine function controlled by the vertebrate hypothalamic-pituitary-gonadal (HPG) axis via different mechanisms/modes of action (MOA). Antagonism of the androgen receptor (AR)...

  6. Competitive binding comparison of endocrine-disrupting compounds to recombinant androgen receptor from fathead minnow, rainbow trout, and human

    EPA Science Inventory

    Typically, in vitro hazard assessments for the identification of endocrine-disrupting compounds (EDCs), including those outlined in the Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC) Tier 1 Screening protocols, utilize mammalian receptors. Evidence, however...

  7. Endocrine disruption by di-(2-ethylhexyl)-phthalate in Chinese rare minnow (Gobiocypris rarus).

    PubMed

    Wang, Xiaofang; Yang, Yuanjin; Zhang, Liping; Ma, Yanbo; Han, Jian; Yang, Lihua; Zhou, Bingsheng

    2013-08-01

    Great concern has been raised over the potential impact of environmental contaminants on fish populations that inhabit the Three Gorge Reservoir. The present study investigated the endocrine-disrupting effects of di-(2-ethylhexyl)-phthalate (DEHP) on the Chinese rare minnow (Gobiocypris rarus), an endemic fish distributed in upstream waters in the Yangtze River. Adult rare minnow were exposed to environmentally relevant concentrations of DEHP (0 µg/L, 3.6 µg/L, 12.8 µg/L, 39.4 µg/L, and 117.6 µg/L) for a 21-d period. Then, concentrations of sex hormones in the plasma and relative transcription of various associated genes were measured in the hypothalamic-pituitary-gonadal (HPG) axis and liver of the fish. Exposure to DEHP resulted in greater circulating concentrations of testosterone (T) and lower concentrations of estradiol (E2), which were accompanied by upregulation of Cyp17 mRNA and downregulation of Cyp19a mRNA in the gonads of females. In males, increases of T and E2 levels were consistent with upregulation of Cyp17 and Cyp19a in the gonads. Furthermore, the T/E2 ratio was increased in females but reduced in males. A significant increase in the levels of hepatic vitellogenin (VTG) gene transcription was observed in both females and males. The present study showed that waterborne exposure to DEHP altered plasma sex hormone levels and modulated gene transcription profiles of associated genes in the HPG axis and liver, occurring mostly at higher concentrations (>39.4 µg/L), which suggests that environmental concentration of DEHP (5.4 µg/L) alone might not disturb the endocrine system of the rare minnow in the TGR.

  8. Testicular transcript responses in rare minnow Gobiocypris rarus following different concentrations bisphenol A exposure.

    PubMed

    Zhang, Yingying; Yuan, Cong; Gao, Jiancao; Liu, Yan; Wang, Zaizhao

    2016-08-01

    Bisphenol A (BPA) is widely spread in the environment. It can cause various reproductive disrupting effects on different organisms, including fish. To investigate the effect of BPA at different concentrations comprehensively, RNA-seq was performed on the testicular mRNA libraries of adult male rare minnow Gobiocypris rarus that exposed to 0, 1, 15 and 225 μg/L BPA for 7 days. Meanwhile, biological indicators and sex steroid hormone levels were investigated. Result showed that (1) BPA at all three concentrations affected the expression of genes related to testicular steroid hormone biosynthesis, blood-testis barrier, proteolysis, and lipid transport and metabolism. (2) BPA at 1 μg/L induced gene expression in renin-angiotensin system pathway and possibly initiate membrane form of estrogen receptor (mER); 1 and 15 μg/L BPA inhibited tRNA processing-related genes expression; 15 and 225 μg/L BPA decreased hemostasis and blood coagulation-related gene expression. The present study indicated that BPA did influence rare minnow testicular gene expressing, and the effect BPA effects varied with concentration. PMID:27183338

  9. VITELLOGENIN EXPRESSION IN SHEEPSHEAD MINNOWS FROM THE PENSACOLA BAY SYSTEM

    EPA Science Inventory

    Hemmer, M.J., B.L. Hemmer, S.D. Friedman and P.S. Harris. In press. Vitellogenin Expression in Populations of Sheepshead Minnows from the Pensacola Bay System (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R1015). <...

  10. Tolerance of the sheepshead minnow, (Cyprinodon variegatus), to selected environmental and chemical challenges

    SciTech Connect

    Bennett, W.A.; Elkan, A.; Mayer, F.L.; Beitinger, T.L.

    1995-12-31

    The sheepshead minnow is the most widely used vertebrate for estuarine toxicity testing, yet little is known about its autecology or toxicant susceptibility relative to other fishes. Sheepshead minnows are more tolerant of temperature, salinity and hypoxic extremes than are any known teleost species. The ecological and physiological thermo-tolerance polygons for sheepshead minnow (1,380 C and 1,470 C) are the largest ever measured for a fish. Sheepshead minnows are osmoregulators at ambient salinities between 0 and 70% and can survive salinity > 180{per_thousand} for extended periods. In addition, sheepshead minnows exposed to progressive hypoxia have an oxygen tolerance of 0.22 mg/l (EC50, equilibrium). This exceptional tolerance of abiotic challenges is also apparent in the sheepshead minnow`s atypical response to toxicant exposure. The US EPA aquatic toxicity database AQUIRE lists 153 different toxicants for which sheepshead minnows have been tested since about 1970. For more than 50% of these toxicants, sheepshead minnows are the only species tested. Interspecific toxicity comparisons of the remaining toxicants are limited to 28 due to dissimilar test parameters. For 63% of these toxicants, sheepshead minnows proved to be the most tolerant (i.e., greatest LC50 value). In contrast, these fish are most sensitive to only 20% of the toxicants and are never the most sensitive in instances where at least two other species were tested. In addition to demonstrating the fish`s tolerance of natural and anthropogenic abiotic challenges, these data emphasize the need for a greater understanding of the physiological and toxicological relationships among sheepshead minnows and other fishes if meaningful interpretations are to be made.

  11. Transcriptome profiling analysis of rare minnow (Gobiocypris rarus) gills after waterborne cadmium exposure.

    PubMed

    Wang, Zhi-Jian; Liu, Xiao-Hong; Jin, Li; Pu, De-Yong; Huang, Jing; Zhang, Yao-Guang

    2016-09-01

    Rare minnow (Gobiocypris rarus) is a widely used experimental fish in risk assessments of aquatic pollutants in China. Cadmium (Cd) is one of the most toxic heavy metals in the world; however, few studies have used fish gills, a multi-functional organ. In this study, we characterized the differential expression of adult female rare minnow gills after sub-chronic waterborne Cd (75μg/L CdCl2) exposure for 35d. A total of 452 genes (209 up-regulated and 243 down-regulated) were identified by gene expression profiling using RNA-Seq before and after treatment. Of these differentially expressed genes, 75, 21, and 54 differentially expressed genes are related to ion transport, oxidation-reduction processes, and the immune response, respectively. The results of GO and KEGG enrichment analyses, together with the altered transcript levels of major histocompatibility complex (MHC) class I and class II molecules and the significant increases in the levels of serum tumor necrosis factor α (TNF-α), interleukin 1β (IL1β) and nuclear factor-κB (NF-κB), indicated a disruption of the immune system, particularly the induction of inflammation and autoimmunity. The significant down-regulation of coagulation factor XIII A1 polypeptide (F13A1), tripartite motif-containing protein 21 (TRIM21), and Golgi-associated plant pathogenesis-related protein (GAPr) during both acute (≤96h) and sub-chronic (35d) waterborne Cd exposure, as well as their dosage dependence, suggested that these three genes could be used as sensitive biomarkers for aquatic Cd risk assessment. PMID:27292131

  12. An intergeneric hybrid of a native minnow, the golden shiner, and an exotic minnow, the rudd

    USGS Publications Warehouse

    Burkhead, N.M.; Williams, J.D.

    1991-01-01

    The hybrid golden shiner Notemigonus crysoleucas × rudd Scardinius erythrophthalmus is the first known nonsalmonid, intergeneric hybrid of an exotic species and a North American native species. The cross is also the first valid record of a viable hybrid involving the native golden shiner. Meristic and mensural characters of 30 artificially produced hybrids of male golden shiners and female rudds were analyzed. Forty-seven percent of the meristic traits exhibited character states intermediate between those of parents. Twenty-seven percent of the meristic characters were supernumerary, suggesting developmental instability of the hybrid genome. Mensural hybrid characters were significantly skewed to the golden shiner phenotype. The skewed mensural inheritance and other skewed patterns of morphological inheritance also suggest problems in canalization of the hybrid phenome or atypical patterns of dominance. All hybrids were identifiable by intermediate squamation of the cultrate abdomen: the keel was mostly scaled but exhibited a small fleshy ridge posteriorly. This minnow hybrid allows general inferences to be made about the phylogenetic affinity of the golden shiner to other cultrate cyprinids of Eurasia. The hybrid cross has important management and conservation implications for fishes in North America. The hybrid is an example of how an exotic species may negatively affect a native species.

  13. Predicting the toxicity of major ions in seawater to mysid shrimp (Mysidopsis bahia), sheepshead minnow (Cyprinodon variegatus), and inland silverside minnow (Menidia beryllina)

    SciTech Connect

    Pillard, D.A.; DuFresne, D.L.; Caudle, D.D.; Tietge, J.E.; Evans, J.M.

    2000-01-01

    Although marine organisms are naturally adapted to salinities well above those of freshwater, elevated concentrations of specific ions have been shown to cause adverse effects on some saltwater species. Because some ions are also physiologically essential, a deficiency of these ions can also cause significant effects. To provide a predictive tool to assess toxicity associated with major ions, mysid shrimp (Mysidopsis bahia), sheepshead minnows (Cyprinodon variegatus), and inland silverside minnows (Menidia beryllina) were exposed to saline solutions containing calcium, magnesium, potassium, strontium, bicarbonate, borate, bromide, and sulfate at concentrations above and below what would be found in seawater. Solution salinity was maintained at approximately 31% by increasing or decreasing sodium and chloride concentrations. Logistic regression models were developed with both the ion molar concentrations and ion activity. Toxicity to all three species was observed when either a deficiency or an excess of potassium and calcium occurred. Significant mortality occurred in all species when exposed to excess concentrations of magnesium, bicarbonate, and borate. The response to the remaining ions varied with species. Sheepshead minnows were the most tolerant of both deficient and elevated levels of the different ions. Mysid shrimp and inland silverside minnows demonstrated similar sensitivities to several ions, but silverside minnow response was more variable. As a result, the logistic models that predict inland silverside minnow survival generally were less robust than for the other two species.

  14. ASSOCIATIONS BETWEEN GENETIC DIVERSITY AND ANTHROPOGENIC DISTURBANCE IN MIDWESTERN STREAM-DWELLING MINNOWS

    EPA Science Inventory

    Anthropogenic disturbances may leave imprints on patterns of intraspecific genetic diversity through their effects on population size, adaptation, migration, and mutation. We examined patterns of genetic diversity for a stream-dwelling minnow (the central stoneroller, Campostoma...

  15. OOCYTE ENVELOPE PROTEINS AND VITELLOGENIN IN MALE SHEEPHEAD MINNOW EXPOSED TO ESTRADIOL

    EPA Science Inventory

    Oocyte Envelope Proteins and Vitellogenin Expression in Male Sheepshead Minnows Exposed to Estradiol (Abstract). To be presented at the 22nd Annual Meeting of the Society of Environmental Toxicology and Chemistry: Changing Environmental Awareness: Societal Concerns and Scientifi...

  16. Comparison of Cultured and Wild Sheepshead Minnow (Cyprinodon variegatus) Health Condition Metrics

    EPA Science Inventory

    Four standard health condition metrics (hepatosomatic index, HSI; gonadosomatic index, GSI; fecundity, condition factor) were compared between cultured and wild caught sheepshead minnow (Cyrprinodon variegatus) to determine if laboratory cultured were representative of wild popul...

  17. Use of NMR-based Metabolite Profiling to Study Responses of Fathead Minnows Exposed to the Potent Androgen 17β-trenbolone

    EPA Science Inventory

    Exposure of organisms in aquatic ecosystems to chemicals which possess endocrine disrupting properties can produce numerous detrimental effects. Furthermore, due to the potency of these chemicals, even relatively low level exposures can reduce fitness. As a result, classical expo...

  18. VITELLOGENIN GENE EXPRESSION IN FATHEAD MINNOWS AND PEARL DACE FROM CONTROL (NON-DOSED) AND LAKES DOSED WITH EE2 IN THE CANADIAN EXPERIMENTAL LAKES AREA

    EPA Science Inventory

    A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA) in northwestern Ontario for three years beginning in 2001. This experiment examined population, organismal, biochemical and cellular-level effects in la...

  19. AROMATASE-B (CYP 19B) EXPRESSION IN FATHEAD MINNOWS (PIMEPHALES PROMELAS) EXPOSED TO PERFLUOROOCTANE (PFOS) AND THE AROMATASE INHIBITOR FADROZOLE

    EPA Science Inventory

    Perfluorooctane sulfonate (PFOS) is a fluorinated organic contaminant that is globally distributed in both humans and wildlife. PFOS belongs to a family of perfluorinated sulfonates that are highly persistent in the environment and have been commercially produced for over 40 year...

  20. RECOMBINANT ANDROGEN RECEPTOR (AR) BINDING ACROSS VERTEBRATE SPECIES: COMPARISON OF BINDING OF ENVIRONMENTAL COMPOUNDS TO HUMAN, RAINBOW TROUT AND FATHEAD MINNOW AR.

    EPA Science Inventory

    In vitro screening assays designed to identify androgen mimics or antagonists typically use mammalian (rat, human) androgen receptors (AR). Although the amino acid sequences of receptors from nonmammalian vertebrates are not identical to the mammalian receptors, it is uncertain ...

  1. Effects of a short-term exposure to the aromatase inhibitor fadrozole on steroid production and gene expression in the ovary of female fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Cytochrome P450 aromatase is a steriodogenic enzyme that converts C19 androgens to C18 estrogens and is critical for normal reproduction in females. Fadrozole is a well-studied aromatase inhibitor that has been shown to suppress estrogen production in the ovaries of fish. Howev...

  2. Influence of water quality on silver toxicity to rainbow trout (Oncorhynchus mykiss), fathead minnows (Pimephales promelas), and water fleas (Daphnia magna)

    SciTech Connect

    Karen, D.J.; Ownby, D.R.; Forsythe, B.L.; Bills, T.P.; La Point, T.W.; Cobb, G.B.; Klaine, S.J.

    1999-01-01

    Toxicity bioassays were conducted to quantify water quality conditions under which silver, as silver nitrate, is toxic to Oncorhynchus mykiss. Pimephales promelas, and Daphnia magna. Bioassays for P. promelas and D. magna were conducted as static replacement tests, whereas a flow-through bioassay system was modified and used for O. mykiss. Results from 96-h toxicity bioassays for O. mykiss indicated that chloride, hardness, and dissolved organic carbon (DOC) protected against silver toxicosis, with DOC affording the highest protective effects. For P. promelas and D. magna, little protection was provided by increased CaCo+O{sub 3} alone, whereas DOC had a major ameliorating influence on measured silver toxicity. Lower concentrations of chloride had little effect on reducing silver nitrate toxicity. Dissolved organic carbon was more important than hardness for predicting the toxicity of ionic silver in natural waters to O. mykiss, P. promelas, and D. magna. Similarly, DOC significantly reduced silver nitrate toxicity to trout, whereas Cl{sup {minus}} and hardness had only a minor protective effect. However, Cl{sup {minus}}/DOC mixtures showed a greater-than-additive protective effect. Thus, the authors suggest that incorporating an organic carbon coefficient into the silver criterion equation will enhance the criterion values for site specificity.

  3. Use of a 15 k gene microarray to determine gene expression changes in response to acute and chronic methylmercury exposure in the fathead minnow Pimephales promelas Rafinesque

    USGS Publications Warehouse

    Klaper, R.; Carter, Barbara J.; Richter, C.A.; Drevnick, P.E.; Sandheinrich, M.B.; Tillitt, D.E.

    2008-01-01

    This study describes the use of a 15 000 gene microarray developed for the toxicological model species, Pimephales promelas, in investigating the impact of acute and chronic methylmercury exposures in male gonad and liver tissues. The results show significant differences in the individual genes that were differentially expressed in response to each treatment. In liver, a total of 650 genes exhibited significantly (P < 0.05) altered expression with greater than two-fold differences from the controls in response to acute exposure and a total of 267 genes were differentially expressed in response to chronic exposure. A majority of these genes were downregulated rather than upregulated. Fewer genes were altered in gonad than in liver at both timepoints. A total of 212 genes were differentially expressed in response to acute exposure and 155 genes were altered in response to chronic exposure. Despite the differences in individual genes expressed across treatments, the functional categories that altered genes were associated with showed some similarities. Of interest in light of other studies involving the effects of methylmercury on fish, several genes associated with apoptosis were upregulated in response to both acute and chronic exposures. Induction of apoptosis has been associated with effects on reproduction seen in the previous studies. This study demonstrates the utility of microarray analysis for investigations of the physiological effects of toxicants as well as the time-course of effects that may take place. In addition, it is the first publication to demonstrate the use of this new 15 000 gene microarray for fish biology and toxicology. ?? 2008 The Authors.

  4. A field-based approach for assessing the impact of paper pulp mill effluent on the metbolite profile of fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Although evidence indicates that exposure to effluent from paper pulp mills (PME) can alter the body condition, secondary sexual characteristics, and reproductive success of aquatic organisms, there is currently little understanding of the biochemical mechanisms for these effects...

  5. Mixtures of 17â-trenbolone with Ethinylestradiol or Bisphenol A Altered Tubercle Formation and Steroid Production in the Fathead Minnow

    EPA Science Inventory

    The xenoestrogens, ethinylestradiol (EE2) and bisphenol A (BPA), and the androgen 17â-trenbolone (TRB) are examples of endocrine disrupting compounds (EDCs) commonly detected in the environment. All have been shown to affect fish reproductive endocrinology individually, but littl...

  6. DIFFERENCES IN THE STRUCTURE AND FUNCTION OF FATHEAD MINNOW AND HUMAN ERA: IMPLICATIONS FOR IN VITRO TESTING OF ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Mammalian receptors and assay systems are generally used for in vitro analysis of endocrine disrupting chemicals (EDC) with the assumption that minor differences in amino acid sequences among species do not translate into significant differences in receptor function. We have fou...

  7. Evaluation of Sex-specific Responses to Trenbolone Acetate Metabolites in Early Life-stage Fathead Minnows (Pimephales promelas) Using Molecular Tools

    EPA Science Inventory

    The occurrence of endocrine disrupting chemicals (EDCs) in concentrated animal feed operation (CAFO) waste, and the potential effects of these chemicals on aquatic ecosystems have been of recent concern, especially in large agricultural regions. Currently, little is known concer...

  8. Pathway-based approaches for assessment of real-time exposure to an estrogenic wastewater treatment plant effluent on fathead minnow reproduction

    EPA Science Inventory

    Wastewater treatment plant (WWTP) effluents are known contributors of chemical mixtures into the environment. Of particular concern are endocrine-disrupting compounds, such as estrogens, that can affect hypothalamic-pituitary-gonadal axis function in exposed organisms. The presen...

  9. Determining the effects of a mixture of an endocrine disrupting compound, 17a-ethinylestradiol, and ammonia on fathead minnow (Pimephales promelas) reproduction

    EPA Science Inventory

    Aquatic organisms are exposed to a multitude of contaminants and to fully understand the impact of multiple stressors on fish populations, we must first understand the mechanism of action for each toxicant and how the combined effects manifest at the level of the individual. 17α-...

  10. THE PATH FROM MOLECULAR INDICATORS OF EXPOSURE TO DESCRIBING DYNAMIC BIOLOGICAL SYSTEMS IN AN AQUATIC ORGANISM: MICROARRAYS AND THE FATHEAD MINNOW

    EPA Science Inventory

    The extent to which humans and wildlife are exposed to toxicants is an important focus of environmental research. This work has been directed toward the development of molecular indicators diagnostic for exposure to various stressors in freshwater fish. Research includes the di...

  11. A Computational Model of the Hypothalamic Pituitary Gonadal Axis in Female Fathead Minnows (Pimephales promelas) exposed to 17á-ethynylestradiol and 17â-trenbolone

    EPA Science Inventory

    Endocrine disrupting chemicals (e.g., estrogens, androgens and their mimics) are known to affect reproduction in fish. 17a-ethynylestradiol is a synthetic estrogen used in birth control pills. 17a-trenbolone is a relatively stable metabolite of trenbolone acetate, a synthetic and...

  12. A PHYSIOLOGICALLY BASED COMPUTATIONAL MODEL OF THE BPG AXIS IN FATHEAD MINNOWS: PREDICTING EFFECTS OF ENDOCRINE DISRUPTING CHEMICAL EXPOSURE ON REPRODUCTIVE ENDPOINTS

    EPA Science Inventory

    This presentation describes development and application of a physiologically-based computational model that simulates the brain-pituitary-gonadal (BPG) axis and other endpoints important in reproduction such as concentrations of sex steroid hormones, 17-estradiol, testosterone, a...

  13. A Computational Model of the Hypothalamic-pituitary-gonadal Axis in Male Fathead Minnows Exposed to 17 | *alpha* | -ethinylestradiol and 17 | *beta* | -estradiol

    EPA Science Inventory

    Estrogenic chemicals in the aquatic environment have been shown to cause a variety of reproductive anomalies in fish including full sex reversal, intersex, and altered population sex ratios. Two estrogens found in the aquatic environment, 17-ethinylestradiol and 17â-estradiol, h...

  14. CLONING AND IN VITRO EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR α FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists typically use mammalian (rat, human) estrogen (ER) and androgen receptors (AR). Although we know that the amino acid sequences of steroid receptors in nonmammalian vertebrates are not identical to the ma...

  15. EFFECTS OF AMMONIUM SULFATE ON GROWTH OF LARVAL NORTHWESTERN SALAMANDERS, RED-LEGGED AND PACIFIC TREEFROG TADPOLES, AND JUVENILE FATHEAD MINNOWS

    EPA Science Inventory

    Ammonium-nitrogen fertilizers are used in large quantities in agricultural areas of the United States, including the grass-seed fields of the Willamette Valley of western Oregon, and are a potential threat to larval amphibians living in the treat areas (Edwards and Daniel 1994, M...

  16. An Individual-based Model for Extrapolating Standard Toxicity Test Data into Population-level Adverse Outcomes in the Fathead Minnow

    EPA Science Inventory

    While environmental toxicity testing typically focuses on organism-level endpoints such as mortality, growth, and reproduction, risk assessment guidelines specify protection goals at the level of the population and above. One method of linking these different levels of biological...

  17. QUANTIFICATION AND ASSOCIATED VARIABILITY OF INDUCED VITELLOGENIN GENE TRANSCRIPTS IN FATHEAD MINNOW (PIMEPHALES PROMELAS) BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION ASSAY

    EPA Science Inventory

    Ecological risk assessors have a growing need for sensitive and rapid indicators of environmental exposure in aquatic ecosystems resulting from natural and synthetic estrogen-like compounds. Investigators developing subcellular exposure markers in traditional sentinel organisms m...

  18. Evaluation of the Methoxytriazine Herbicide Prometon Using a Short-term Fathead Minnow Reproduction Test and a Suite of in vitro Bioassays

    EPA Science Inventory

    This study used an array of in vitro bioassays to assess whether prometon, atraton, terbumeton, or secbumeton might act as potent (ant)agonists of the aryl hydrocarbon, estrogen, androgen, or glucocorticoid receptors and whether they might act as aromatase inhibitors or inducers ...

  19. Predicting fecundity of fathead minnows (Pimephales promelas) exposed toeEndocrine-disrupting chemicals using a MATLAB®-based model of oocyte growth dynamics

    EPA Science Inventory

    Fish spawning is often used as an integrated measure of reproductive toxicity, and an indicator of aquatic ecosystem health in the context of forecasting potential population-level effects considered important for ecological risk assessment. Consequently, there is a need for fle...

  20. Comparative responses in rare minnow exposed to 17beta-estradiol during different life stages.

    PubMed

    Liao, T; Guo, Q L; Jin, S W; Cheng, W; Xu, Y

    2009-08-01

    Present in the excrement of humans and animals, 17beta-estradiol (E(2)) has been detected in the aquatic environment in a range from several nanograms to several hundred nanograms per liter. In this study, the sensitivities of rare minnows during different life stages to E(2) at environmentally relevant (5, 25, and 100 ng l(-1)) and high (1000 ng l(-1)) concentrations were compared using vitellogenin (VTG) and gonad development as biomarkers under semistatic conditions. After 21 days of exposure, VTG concentrations in whole-body homogenates were analyzed; the results indicated that the lowest observed effective concentration for VTG induction was 25 ng l(-1) E(2) in the adult stage, but 100 ng l(-1) E(2) in the larval and juvenile stages. After exposure in the early life stage, the larval and juvenile fish were transferred to clean water until gonad maturation. No significant difference in VTG induction was found between the exposure and control groups in the adults. However, a markedly increased proportion of females and appearance of hermaphrodism were observed in the juvenile-stage group exposed to 25 ng l(-1) E(2). These results showed that VTG induction in the adult stage is more sensitive than in larval and juvenile stages following exposure to E(2). The juvenile stage may be the critical period of gonad development. Sex ratio could be a sensitive biomarker indicating exposure to xenoestrogens in early-life-stage subchronic exposure tests. The results of this study provide useful information for selecting sensitive biomarkers properly in aquatic toxicology testing.

  1. Toxicogenomic applications of Chinese rare minnow (Gobiocypris rarus) in aquatic toxicology.

    PubMed

    Liang, Xuefang; Zha, Jinmiao

    2016-09-01

    Rare minnow (Gobiocypris rarus), a Chinese native species, are an excellent emerging model organism for aquatic toxicity testing and chemical safety assessment. "Big data" omics approaches (i.e., genomics, proteomics, and metabolomics) to inform mechanistic toxicology are now applied to studies in rare minnows to better understand toxicity and molecular pathways perturbed by chemicals. This review highlights recent applications of toxicogenomics to study changes in the gene and protein expression profiles in rare minnows in response to chemicals. Here we briefly describe studies that utilized cDNA microarrays in characterization of the cellular effects of rare minnows in single and mixed chemical exposures. Then we compare gel-based proteomics studies in liver of rare minnows following treatment with endocrine disrupting chemicals including 17β-estradiol, 17α-methyltestosterone, pentachlorophenol, and perfluorooctanoic acid. A total of 90 proteins identified in these studies were functionally annotated and categorized. These responsive proteins have roles in biological processes that include metabolism (37.8%), response to oxidation/chemicals (16.7%), signal transduction (11.1%), transport (10%), cytoskeleton (6.7%) and others (17.8%). In addition, recent investigations of endocrine disrupting effects and neurotoxicity of benzotriazole, an emerging contaminant, are summarized. The objective is to continue to enrich genome and protein databases for this species and to integrate molecular datasets to consider temporal effects and complex regulation at the level of the genome and proteome. PMID:27373348

  2. Survey of receiving-water environmental impacts associated with discharges from pulp mills; 1: Mill characteristics, receiving-water chemical profiles and lab toxicity tests

    SciTech Connect

    Robinson, R.D. . Dept. of Environmental Biology); Carey, J.H. . Rivers Research Branch); Solomon, K.R. ); Smith, I.R. . Water Resources Branch); Servos, M.R.; Munkittrick, K.R. . Great Lakes Lab. for Fisheries and Aquatic Sciences)

    1994-07-01

    This survey examined the relationship between environmental responses at pulp mill sites and the pulping process, effluent treatment, and bleaching technology used by pulp mills. This manuscript is the first in a series of four; it reviews the location and operating characteristics of mills included in the survey and provides background information on water chemistry that is relevant to the other components of the survey. In addition, lab 7-d toxicity tests of receiving water were conducted using fathead minnows (Pimephales promelas) and the cladoceran Ceriodaphnia dubia with water samples collected upstream and downstream of effluent discharges at 11 Canadian pulp and paper mills; these samples were collected at the same time as fish surveys were conducted. Survival of fathead minnow larvae was significantly reduced at four of the 11 downstream sites. Ceriodaphnia reproduction was significantly higher at six of the 11 downstream sites and significantly lower at two downstream sites. There were no significant effects on fathead minnow larva growth or adult Ceriodaphnia survival at any of the examined downstream sites. Negative effects in the toxicity tests were generally associated with the low dilution discharge of primary treated effluent with a previous history of acute toxicity. Fathead minnow and Ceriodaphnia tests were generally correlated with historical data on benthic macroinvertebrate community responses. Neither toxicity test predicted the physiological changes in wild fish that are presented in accompanying papers.

  3. INFLUENCE OF SPAWNING GROUP SIZE AND SPACE ON REPRODUCTION BY SHEEPSHEAD MINNOWS, CYPRINODON VARIEGATUS

    EPA Science Inventory

    Cripe, G.M., R.L. Hemmer and L.R. Goodman. In press. Influence of Spawning Group Size and Space on Reproduction Variability of Sheepshead Minnows, Cyprinodon variegatus (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB...

  4. FIELD VALIDATION OF A SHEEPSHEAD MINNOW ESTROGEN-RESPONSIVE CDNA MACROARRAY

    EPA Science Inventory

    Hemmer, Michael J., Iris Knoebl, Becky L. Hemmer, Patrick Larkin, Peggy S. Harris and Nancy D. Denslow. In press. Field Validation of a Sheepshead Minnow Estrogen-Responsive cDNA Macroarray (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portl...

  5. TEMPORAL GENE INDUCTION PATTERNS IN SHEEPSHEAD MINNOWS EXPOSED TO 17-ESTRADIOL

    EPA Science Inventory

    Gene arrays provide a powerful method to examine changes in gene expression in fish due to chemical exposures in the environment. In this study, we expanded an existing gene array for sheepshead minnows (Cyprinodon variegatus) (SHM) and used it to examine temporal changes in gene...

  6. MAXIMIZING GROWTH AND SEXUAL MATURATION OF SHEEPSHEAD MINNOWS IN SUPPORT OF MULTI-GENERATION TEST DEVELOPMENT

    EPA Science Inventory

    Hemmer, R.L., G.M. Cripe and L.R. Goodman. In press. Maximizing Growth and Sexual Maturation of Sheepshead Minnows (Cyprinodon variegatus) in Support of Multi-Generation Test Development (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland...

  7. EXPRESSION PROFILING OF ESTROGENIC COMPOUNDS USING A SHEEPSHEAD MINNOW CDNA MACROARRAY

    EPA Science Inventory

    Larkin, Patrick, Leroy C. Folmar, Michael J. Hemmer, Arianna J. Poston and Nancy D. Denslow. 2003. Expression Profiling of Estrogenic Compounds Using a Sheepshead Minnow cDNA Macroarray. Environ. Health Perspect. 111(6):839-846. (ERL,GB 1171).

    A variety of anthropogenic c...

  8. 75 FR 7625 - Endangered and Threatened Wildlife and Plants; Rio Grande Silvery Minnow (Hybognathus amarus...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-22

    ... Rio Grande silvery minnow was listed as federally endangered in 1994 (July 20, 1994; 59 FR 36988) and critical habitat was designated in 2003 (February 19, 2003; 68 FR 8087). The species was extirpated from... (mi)) reach of the Rio Grande River in New Mexico, downstream of Cochiti Dam to the headwaters...

  9. Comparative acute toxicity to aquatic organisms of components of coal-derived synthetic fuels. [Selenastrum capricornutum; Nitzchia palea; Physa gyrina, Daphnia magna; Chironomus tentans; Gammarus minus; Pimephales promelas; Salmo gairdneri; Micropterus salmoides

    SciTech Connect

    Millemann, R.E.; Birge, W.J.; Black, J.A.; Cushman, R.M.; Daniels, K.L.; Franco, P.J.; Giddings, J.M.; McCarthy, J.F.; Stewart, A.J.

    1984-01-01

    In acute toxicity tests, green algae Selenaastrum capricornutum, diatoms Nitzschia palea, adult snails Physa gyrina, juvenile cladocerans Daphnia magna, larval midges Chironomus tentans, adult amphipods Gammarus minus, juvenile fathead minnows Pimephales promelas, and embryo-larva stages of rainbow trout Salmo gairdneri and largemouth bass Micropterus salmoides were exposed for 4 hours (algae), 48 hours (arthropods and snails), 96 hours (fathead minnows), 7 days (large-mouth bass), and 27 days (rainbow trout) to two phenols (phenol and ..beta..-naphthol), two azaarenes (quinoline and acridine), and two polycyclic aromatic hydrocarbons (naphthalene and phenanthrene) present in coal-derived oils. Median lethal or median effective concentrations (LC50s or EC50s) ranged from 0.03 mg/liter for phenanthrene and rainbow trout to 286.54 mg/liter for phenol and the green alga. The rainbow trout embryo-larva assay was the most sensitive of the test systems to all the chemicals except quinoline. For this last compound, systems with juvenile fathead minnows and largemouth bass embryos were the most sensitive. As test systems, fish embryos and larvae were the most sensitive, juvenile fathead minnows and arthropods had intermediate sensitivity, and algae and snails were the most resistant to the test compounds under the test conditions. Within each chemical class (phenols, azaarenes, and polycylcic aromatic hydrocarbons), toxicity increased with increased ring number except for the reversed relationship with the azaarenes and fathead minnows. Thus, ..beta..-naphthol (two rings) was 2 to 45 times more toxic than phenol (one ring); acridine (three rings) was 7 to 27 times more toxic than quinoline (two rings); and phenanthrene (three rings) was 3 to 9 times more toxic than naphthalene (two rings). 50 references.

  10. An evaluation of the efficiency of minnow traps for estimating the abundance of minnows in desert spring systems

    USGS Publications Warehouse

    Peterson, James T.; Scheerer, Paul D.; Clements, Shaun

    2015-01-01

    Desert springs are sensitive aquatic ecosystems that pose unique challenges to natural resource managers and researchers. Among the most important of these is the need to accurately quantify population parameters for resident fish, particularly when the species are of special conservation concern. We evaluated the efficiency of baited minnow traps for estimating the abundance of two at-risk species, Foskett Speckled Dace Rhinichthys osculus ssp. and Borax Lake Chub Gila boraxobius, in desert spring systems in southeastern Oregon. We evaluated alternative sample designs using simulation and found that capture–recapture designs with four capture occasions would maximize the accuracy of estimates and minimize fish handling. We implemented the design and estimated capture and recapture probabilities using the Huggins closed-capture estimator. Trap capture probabilities averaged 23% and 26% for Foskett Speckled Dace and Borax Lake Chub, respectively, but differed substantially among sample locations, through time, and nonlinearly with fish body size. Recapture probabilities for Foskett Speckled Dace were, on average, 1.6 times greater than (first) capture probabilities, suggesting “trap-happy” behavior. Comparison of population estimates from the Huggins model with the commonly used Lincoln–Petersen estimator indicated that the latter underestimated Foskett Speckled Dace and Borax Lake Chub population size by 48% and by 20%, respectively. These biases were due to variability in capture and recapture probabilities. Simulation of fish monitoring that included the range of capture and recapture probabilities observed indicated that variability in capture and recapture probabilities in time negatively affected the ability to detect annual decreases by up to 20% in fish population size. Failure to account for variability in capture and recapture probabilities can lead to poor quality data and study inferences. Therefore, we recommend that fishery researchers and

  11. Simultaneous exposure to chronic hypoxia and dissolved polycyclic aromatic hydrocarbons results in reduced egg production and larval survival in the sheepshead minnow (Cyprinodon variegatus).

    PubMed

    Hedgpeth, Bryan M; Griffitt, Robert J

    2016-03-01

    Estuarine fish in the northern Gulf of Mexico are exposed annually to hypoxic conditions. In addition to hypoxia, fish located throughout the northern Gulf of Mexico were potentially exposed to oil released during the Deepwater Horizon incident. Therefore, the interaction between oil exposure and hypoxia is worth investigating. To examine this interaction, the authors exposed adult and larval sheepshead minnow (Cyprinodon variegatus) to crude or dispersed oil under both normoxic and hypoxic conditions. The authors examined total egg production, egg hatching success, and larval survival post hatch. The authors' results indicate that co-exposure to crude or dispersed oil and hypoxia resulted in a significant decrease in egg production, as well as a significant decrease in both egg hatch success and larval survival post hatch. The significant impact on reproductive success following crude or dispersed oil and hypoxia exposure indicates the importance of including environmental parameters such as hypoxia when evaluating the impact of an oil spill.

  12. EFFECTS OF P-NONYLPHENOL, METHOXYCHLOR AND ENDOSULFAN ON VITELLOGENIN INDUCTION AND EXPRESSION IN THE SHEEPSHEAD MINNOW, CYPRINODON VARIEGATUS

    EPA Science Inventory

    Temporal and dose-response relationships of vitellogenin (VTG) mRNA induction and subsequent plasma VTG accumulation were established for sheepshead minnows (Cyprinodon variegatus) treated with p-nonylphenol, an alkylphenol, and the organochlorine pesticides methoxychlor and endo...

  13. Comparative toxicokinetics of explosive compounds in sheepshead minnows.

    PubMed

    Lotufo, G R; Lydy, M J

    2005-08-01

    Juvenile sheepshead minnows Cyprinodon variegatus were exposed to the explosive compounds 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and to the TNT transformation products 2-aminodinitrotoluene (2-ADNT) and 2,4-diaminonitrotoluene (2,4-DANT) in five separate water-only experiments. A one-compartment model was used to characterize uptake (k(u)) and elimination (k(e)) rate constants and to estimate bioconcentration factors (BCFs). The compounds investigated in this study are weakly hydrophobic. Kinetically derived BCFs (9.6, 13.1, 0.5, 1.7, and 0.5 ml g(-1) for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively) confirmed the expected low bioaccumulative potential of those compounds and the positive relationship between log BCF and log K(ow) (1.6, 2.0, 0.8, 0.9, and 0.2 for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively). The uptake clearance (k(u)) was relatively slow for all compounds (7.3, 12.6, 1.3, 0.15, and 0.06 ml g(-1)h(-1) for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively), and overall, it decreased with decreasing compound hydrophobicity. Elimination was extremely fast for the nitroaromatic compounds (0.77, 0.96, and 2.74 h(-1) for TNT, 2-ADNT, and 2,4-DANT, respectively), thus resulting in very short biological half-lives (<1 hour), but it was much slower for the cyclonitramines (0.09 h(-1) for RDX and 0.12 h(-1) for HMX). Although ADNTs were present in fish exposed to TNT, the parent compound was the dominant compound in tissues during the uptake and elimination exposures. The rates of metabolite formation (0.06 h(-1)) and elimination (0.16 h(-1)) were much slower than the rate of elimination of the parent compound (0.80 h(-1)). Because of the fast elimination rate of TNT and its transformation products and the exceedingly low bioaccumulative potential of RDX and HMX, exposure conditions likely associated with the presence of explosives in aquatic systems are

  14. Comparative toxicokinetics of explosive compounds in sheepshead minnows.

    PubMed

    Lotufo, G R; Lydy, M J

    2005-08-01

    Juvenile sheepshead minnows Cyprinodon variegatus were exposed to the explosive compounds 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and to the TNT transformation products 2-aminodinitrotoluene (2-ADNT) and 2,4-diaminonitrotoluene (2,4-DANT) in five separate water-only experiments. A one-compartment model was used to characterize uptake (k(u)) and elimination (k(e)) rate constants and to estimate bioconcentration factors (BCFs). The compounds investigated in this study are weakly hydrophobic. Kinetically derived BCFs (9.6, 13.1, 0.5, 1.7, and 0.5 ml g(-1) for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively) confirmed the expected low bioaccumulative potential of those compounds and the positive relationship between log BCF and log K(ow) (1.6, 2.0, 0.8, 0.9, and 0.2 for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively). The uptake clearance (k(u)) was relatively slow for all compounds (7.3, 12.6, 1.3, 0.15, and 0.06 ml g(-1)h(-1) for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively), and overall, it decreased with decreasing compound hydrophobicity. Elimination was extremely fast for the nitroaromatic compounds (0.77, 0.96, and 2.74 h(-1) for TNT, 2-ADNT, and 2,4-DANT, respectively), thus resulting in very short biological half-lives (<1 hour), but it was much slower for the cyclonitramines (0.09 h(-1) for RDX and 0.12 h(-1) for HMX). Although ADNTs were present in fish exposed to TNT, the parent compound was the dominant compound in tissues during the uptake and elimination exposures. The rates of metabolite formation (0.06 h(-1)) and elimination (0.16 h(-1)) were much slower than the rate of elimination of the parent compound (0.80 h(-1)). Because of the fast elimination rate of TNT and its transformation products and the exceedingly low bioaccumulative potential of RDX and HMX, exposure conditions likely associated with the presence of explosives in aquatic systems are

  15. Hepatic expression patterns of aryl hydrocarbon receptor, pregnane X receptor, two cytochrome P450s and five phase II metabolism genes responsive to 17alpha-methyltestosterone in rare minnow Gobiocypris rarus.

    PubMed

    Gao, Jiancao; Liu, Shaozhen; Zhang, Yingying; Yuan, Cong; Yang, Yanping; Wang, Zaizhao

    2014-05-01

    17Alpha-methyltestosterone (MT), a synthetic androgen, is widely used in aquaculture. Aquatic organisms can receive continuous exposure to residual MT throughout their lives. Aiming to evaluate the effects of MT on genes involved in biotransformation pathway, meanwhile attempting to unravel the MT metabolic pathway at the transcriptional level in fish, here we isolated the cDNAs of previously unreported AHR2, Sult1 st1, Ugt2a1 and Ugt2b6 in rare minnow, and predominantly investigated the hepatic transcriptional patterns of AHR2, PXR and five biotransformation genes after MT exposure in both genders adult rare minnow Gobiocypris rarus. The present findings suggest that AHR2 and PXR should play important roles in regulating biotransformation enzymes related to MT catabolism, moreover, CYP1A, CYP3A, SULT1 ST4, SULT1 ST6 and UGT2A1 may play certain roles in catabolism of MT in adult G. rarus. Additionally, UGT2A1 may make greater contribution than SULT1 ST4 and SULT1 ST6 in MT catabolism in males.

  16. Hepatic expression patterns of aryl hydrocarbon receptor, pregnane X receptor, two cytochrome P450s and five phase II metabolism genes responsive to 17alpha-methyltestosterone in rare minnow Gobiocypris rarus.

    PubMed

    Gao, Jiancao; Liu, Shaozhen; Zhang, Yingying; Yuan, Cong; Yang, Yanping; Wang, Zaizhao

    2014-05-01

    17Alpha-methyltestosterone (MT), a synthetic androgen, is widely used in aquaculture. Aquatic organisms can receive continuous exposure to residual MT throughout their lives. Aiming to evaluate the effects of MT on genes involved in biotransformation pathway, meanwhile attempting to unravel the MT metabolic pathway at the transcriptional level in fish, here we isolated the cDNAs of previously unreported AHR2, Sult1 st1, Ugt2a1 and Ugt2b6 in rare minnow, and predominantly investigated the hepatic transcriptional patterns of AHR2, PXR and five biotransformation genes after MT exposure in both genders adult rare minnow Gobiocypris rarus. The present findings suggest that AHR2 and PXR should play important roles in regulating biotransformation enzymes related to MT catabolism, moreover, CYP1A, CYP3A, SULT1 ST4, SULT1 ST6 and UGT2A1 may play certain roles in catabolism of MT in adult G. rarus. Additionally, UGT2A1 may make greater contribution than SULT1 ST4 and SULT1 ST6 in MT catabolism in males. PMID:24814259

  17. Complete mitochondrial genome of the Moltrecht's minnow, Aphyocypris moltrechti (Teleostei, Cyprinidae), in comparison with A. kikuchii.

    PubMed

    Jang-Liaw, Nian-Hong; Tsai, Chi-Li; Chang, Chia-Hao; Watanabe, Katsutoshi

    2013-04-01

    We sequenced the complete mitochondrial genome of the Moltrecht's minnow, Aphyocypris moltrechti, which is known as an endemic species to Taiwan. The complete mitochondrial genome is 16,617 bp in size, consisting of 37 genes coding for 13 proteins, 2 rRNAs, 22 tRNAs, and 1 control region. Its gene arrangement pattern was identical with most vertebrates. We compared the mitochondrial genome of A. moltrechti with that of the Kikuchi's minnow, Aphyocypris kikuchii, which had been considered closely related to A. moltrechti within a same genus. Nucleotide sequence divergence (K2P distance) between the two whole mitochondrial genomes was 11.62%. The detailed comparison between the mitochondrial genomes of two species was done.

  18. Assessment of 17{alpha}-ethinylestradiol effects and underlying mechanisms in a continuous, multigeneration exposure of the Chinese rare minnow (Gobiocypris rarus)

    SciTech Connect

    Zha Jinmiao; Sun Liwei; Zhou Yiqi; Spear, Philip A.; Ma, Mei; Wang Zijian

    2008-02-01

    17{alpha}-Ethinylestradiol (EE{sub 2}) is a synthetic estrogen used primarily in birth control pills and in hormone replacement therapy. Owing to its occurrence in surface waters at concentrations frequently greater than 1 ng/l and its projected future use, EE{sub 2} is expected to pose a significant risk to aquatic organisms. This study was conducted to obtain long-term exposure data necessary for the establishment of water quality criteria and to investigate mechanisms associated with toxic effects. In a multigeneration experiment, Chinese rare minnows (Gobiocypris rarus) were constantly exposed to environmentally relevant concentrations of the synthetic estrogen EE{sub 2}. Mortality, deformities, reproductive parameters, plasma vitellogenin and histopathology were assessed. The results showed that, in the F{sub 0} generation, all endpoints were significantly affected at concentrations higher than 0.2 ng/l EE{sub 2}. No F{sub 1} phenotypic males developed to maturity at 0.2 ng/l and, when adult females of this exposure group were crossed with unexposed males, no F{sub 2} fertile eggs were produced. Kidney histopathology and ultrastructure suggest anomalies possibly associated with increased vitellogenin accumulation. We concluded that the reproduction of the F{sub 1} minnows was completely inhibited at the lowest concentration tested, 0.2 ng/l EE{sub 2}, a concentration frequently detected in surface waters. Growth effects may be related to increased energy requirements including the energy used in VTG synthesis. Reproductive effects are presumably associated with male feminization and the occurrence of testis-ova in males; however, ovarian degeneration observed in females may also have contributed to reproductive failure.

  19. Asymmetric thermal acclimation responses allow sheepshead minnow Cyprinodon variegatus to cope with rapidly changing temperatures.

    PubMed

    Fangue, Nann A; Wunderly, Martin A; Dabruzzi, Theresa F; Bennett, Wayne A

    2014-01-01

    Thermal acclimation responses in sheepshead minnow Cyprinodon variegatus were quantified by transfer and reciprocal transfer of fish between 11.1° and 18.2°C, between 18.2° and 25.7°C, or between 25.7° and 32.8°C. Changes in thermal acclimation status were assessed by posttransfer time series determinations of thermal tolerance (i.e., critical thermal minima and maxima). In general, heat tolerance gain and loss were complete in 20 and 25 d, respectively. Cold tolerance gain was achieved ca. 24 d posttransfer, but attrition was complete after only 12-13 d. Heat tolerance was gained asymmetrically, with fish acquiring approximately one-half of their accruable tolerance at the lowest transfer temperature. Likewise, the majority of cold tolerance accruement occurred during the warmest temperature transfer. Relatively uniform losses of heat and cold tolerance were seen in reciprocal transfers. Acclimation patterns were related to initial acclimation temperature, final acclimation temperature, and acclimation time and could be accurately modeled by multiple linear regression. The results suggest that sheepshead minnow accrue a majority of their high- or low-temperature tolerance early in the acclimation process well before potential damaging temperatures are likely to occur. This novel pattern of asymmetric heat and cold tolerance acquisition in sheepshead minnow may be a key adaptation for surviving rapid and unpredictable water temperature changes commonly encountered in their natural environment. PMID:25461645

  20. Biogeography and divergent patterns of body size disparification in North American minnows.

    PubMed

    Martin, Samuel D; Bonett, Ronald M

    2015-12-01

    Body size is one of the most important traits influencing an organism's ecology and a major axis of evolutionary change. We examined body size disparification in the highly speciose North American minnows (Cyprinidae), which exhibit diverse body sizes and ecologies, including the giant piscivorous pikeminnows. We estimated a novel phylogeny for 285 species based on a supermatrix alignment of seven mitochondrial and ten nuclear genes, and used this to reconstruct ancestral body sizes (log-total length) and ancestral area. Additionally, given that fishes inhabiting Pacific drainages have historically been subjected to frequent local extinctions due to periodic flooding, droughts, and low drainage connectivity, we also compared body size disparification between the highly speciose Atlantic drainages and comparatively depauperate Pacific drainages. We found that dispersal between Atlantic and Pacific drainages has been infrequent and generally occurred in minnows with southerly distributions, where drainage systems are younger and less stable. The long isolation between Atlantic and Pacific drainages has allowed for divergent patterns of morphological disparification; we found higher rates of body size disparification in minnows from the environmentally harsher Pacific drainages. We propose several possible explanations for the observed patterns of size disparification in the context of habitat stability, niche space, and species diversification. PMID:26210938

  1. SURROGATE SPECIES IN ASSESSING CONTAMINANT RISK FOR ENDANGERED FISHES

    EPA Science Inventory

    Rainbow trout, fathead minnows, and sheepshead minnows were tested as surrogate species to assess contaminant risk for 17 endangered fishes and one toad species. Acute toxicity tests were conducted with carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin in accord...

  2. SURROGATE SPECIES IN ASSESSING CONTAMINANT RISK FOR ENDANGERED FISHES, INCLUDING INTERSPECIES TOXICITY CORRELATIONS

    EPA Science Inventory

    Rainbow trout, fathead minnows, and sheepshead minnows were tested as surrogate species to assess contaminant risk for 17 endangered fishes and one toad species. Acute toxicity tests were conducted with carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin in accorda...

  3. Quantitative PCR Assays for Detecting Loach Minnow (Rhinichthys cobitis) and Spikedace (Meda fulgida) in the Southwestern United States.

    PubMed

    Dysthe, Joseph C; Carim, Kellie J; Paroz, Yvette M; McKelvey, Kevin S; Young, Michael K; Schwartz, Michael K

    2016-01-01

    Loach minnow (Rhinichthys cobitis) and spikedace (Meda fulgida) are legally protected with the status of Endangered under the U.S. Endangered Species Act and are endemic to the Gila River basin of Arizona and New Mexico. Efficient and sensitive methods for monitoring these species' distributions are critical for prioritizing conservation efforts. We developed quantitative PCR assays for detecting loach minnow and spikedace DNA in environmental samples. Each assay reliably detected low concentrations of target DNA without detection of non-target species, including other cyprinid fishes with which they co-occur.

  4. Quantitative PCR Assays for Detecting Loach Minnow (Rhinichthys cobitis) and Spikedace (Meda fulgida) in the Southwestern United States.

    PubMed

    Dysthe, Joseph C; Carim, Kellie J; Paroz, Yvette M; McKelvey, Kevin S; Young, Michael K; Schwartz, Michael K

    2016-01-01

    Loach minnow (Rhinichthys cobitis) and spikedace (Meda fulgida) are legally protected with the status of Endangered under the U.S. Endangered Species Act and are endemic to the Gila River basin of Arizona and New Mexico. Efficient and sensitive methods for monitoring these species' distributions are critical for prioritizing conservation efforts. We developed quantitative PCR assays for detecting loach minnow and spikedace DNA in environmental samples. Each assay reliably detected low concentrations of target DNA without detection of non-target species, including other cyprinid fishes with which they co-occur. PMID:27583576

  5. Quantitative PCR Assays for Detecting Loach Minnow (Rhinichthys cobitis) and Spikedace (Meda fulgida) in the Southwestern United States

    PubMed Central

    Carim, Kellie J.; Paroz, Yvette M.; McKelvey, Kevin S.; Young, Michael K.; Schwartz, Michael K.

    2016-01-01

    Loach minnow (Rhinichthys cobitis) and spikedace (Meda fulgida) are legally protected with the status of Endangered under the U.S. Endangered Species Act and are endemic to the Gila River basin of Arizona and New Mexico. Efficient and sensitive methods for monitoring these species’ distributions are critical for prioritizing conservation efforts. We developed quantitative PCR assays for detecting loach minnow and spikedace DNA in environmental samples. Each assay reliably detected low concentrations of target DNA without detection of non-target species, including other cyprinid fishes with which they co-occur. PMID:27583576

  6. The thyroid gland and thyroid hormones in sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis.

    PubMed

    Schnitzler, Joseph G; Klaren, Peter H M; Mariavelle, Emeline; Das, Krishna

    2016-04-01

    The sheepshead minnow is widely used in ecotoxicological studies that only recently have begun to focus on disruption of the thyroid axis by xenobiotics and endocrine disrupting compounds. However, reference levels of the thyroid prohormone thyroxine (T4) and biologically active hormone 3,5,3'-triiodothyronine (T3) and their developmental patterns are unknown. This study set out to describe the ontogeny and morphology of the thyroid gland in sheepshead minnow, and to correlate these with whole-body concentrations of thyroid hormones during early development and metamorphosis. Eggs were collected by natural spawning in our laboratory. T4 and T3 were extracted from embryos, larvae and juveniles and an enzyme-linked immunoassay was used to measure whole-body hormone levels. Length and body mass, hatching success, gross morphology, thyroid hormone levels and histology were measured. The onset of metamorphosis at 12-day post-hatching coincided with surges in whole-body T4 and T3 concentrations. Thyroid follicles were first observed in pre-metamorphic larvae at hatching and were detected exclusively in the subpharyngeal region, surrounding the ventral aorta. Follicle size and thyrocyte epithelial cell heights varied during development, indicating fluctuations in thyroid hormone synthesis activity. The increase in the whole-body T3/T4 ratio was indicative of an increase in outer ring deiodination activity. This study establishes a baseline for thyroid hormones in sheepshead minnows, which will be useful for the understanding of thyroid hormone functions and in future studies of thyroid toxicants in this species.

  7. Dietary lipid and gross energy affect protein utilization in the rare minnow Gobiocypris rarus

    NASA Astrophysics Data System (ADS)

    Wu, Benli; Xiong, Xiaoqin; Xie, Shouqi; Wang, Jianwei

    2016-07-01

    An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the effects of protein to energy ratio on growth, for the rare minnow ( Gobiocypris rarus), which are critical to nutrition standardization for model fish. Twenty-four diets were formulated to contain three gross energy (10, 12.5, 15 kJ/g), four protein (20%, 25%, 30%, 35%), and two lipid levels (3%, 6%). The results showed that optimal dietary E/P was 41.7-50 kJ/g for maximum growth in juvenile rare minnows at 6% dietary crude lipid. At 3% dietary lipid, specific growth rate (SGR) increased markedly when E/P decreased from 62.5 kJ/g to 35.7 kJ/g and gross energy was 12.5 kJ/g, and from 75 kJ/g to 42.9 kJ/g when gross energy was 15.0 kJ/g. The optimal gross energy was estimated at 12.5 kJ/g and excess energy decreased food intake and growth. Dietary lipid exhibited an apparent protein-sparing effect. Optimal protein decreased from 35% to 25%-30% with an increase in dietary lipid from 3% to 6% without adversely effecting growth. Dietary lipid level affects the optimal dietary E/P ratio. In conclusion, recommended dietary protein and energy for rare minnow are 20%-35% and 10-12.5 kJ/g, respectively.

  8. Toxicogenomic analysis of the hepatic effects of perfluorooctanoic acid on rare minnows (Gobiocypris rarus)

    SciTech Connect

    Wei Yanhong; Liu Yang; Wang Jianshe; Tao Yi; Dai Jiayin

    2008-02-01

    Perfluorooctanoic acid (PFOA) is a ubiquitous environmental contaminant that has been detected in a variety of terrestrial and aquatic organisms. To assess the effects of PFOA in fish and predict its potential mode of action, a toxicogenomic approach was applied to hepatic gene expression profile analysis in male and female rare minnows (Gobiocypris rarus) using a custom cDNA microarray containing 1773 unique genes. Rare minnows were treated with continuous flow-through exposure to PFOA at concentrations of 3, 10, and 30 mg/L for 28 days. Based on the observed histopathological changes, the livers from fish exposed to 10 mg/L PFOA were selected for further hepatic gene expression analysis. While 124 and 171 genes were significantly altered by PFOA in males and females, respectively, of which 43 genes were commonly regulated in both sexes. The affected genes are involved in multiple biological processes, including lipid metabolism and transport, hormone action, immune responses, and mitochondrial functions. PFOA exposure significantly suppressed genes involved in fatty acid biosynthesis and transport but induced genes associated with intracellular trafficking of cholesterol. Alterations in expression of genes associated with mitochondrial fatty acid {beta}-oxidation were only observed in female rare minnows. In addition, PFOA inhibited genes responsible for thyroid hormone biosynthesis and significantly induced estrogen-responsive genes. These findings implicate PFOA in endocrine disruption. This work contributes not only to the elucidation of the potential mode of toxicity of PFOA to aquatic organisms but also to the use of toxicogenomic approaches to address issues in environmental toxicology.

  9. Complete mitochondrial genome of the Kikuchi's minnow Aphyocypris kikuchii (Teleostei, Cyprinidae).

    PubMed

    Jang-Liaw, Nian-Hong; Tsai, Chi-Li; Watanabe, Katsutoshi

    2013-02-01

    We have sequenced the complete mitochondrial genome of the Kikuchi's minnow, Aphyocypris kikuchii (Oshima 1919), which is an endemic species to Taiwan. The complete mitochondrial genome is 16,601 bp in size, containing 37 genes coding for 13 proteins, 2 rRNAs, 22 tRNAs, and 1 control region. It has the typical vertebrate mitochondrial gene arrangement. The sequence information could play an important role in resolving the conflict on its current taxonomic position and preservation of genetic resources for helping conservation of the endangered species.

  10. Comparison of catch per unit effort among four minnow trap models in the three-spined stickleback (Gasterosteus aculeatus) fishery

    PubMed Central

    Budria, Alexandre; DeFaveri, Jacquelin; Merilä, Juha

    2015-01-01

    Minnow traps are commonly used in the stickleback (Gasterostidae) fishery, but the potential differences in catch per unit effort (CPUE) among different minnow trap models are little studied. We compared the CPUE of four different minnow trap models in field experiments conducted with three-spined sticklebacks (Gasterosteus aculeatus). Marked (up to 26 fold) differences in median CPUE among different trap models were observed. Metallic uncoated traps yielded the largest CPUE (2.8 fish/h), followed by metallic black nylon-coated traps (1.3 fish/h). Collapsible canvas traps yielded substantially lower CPUEs (black: 0.7 fish/h; red: 0.1 fish/h) than the metallic traps. Laboratory trials further revealed significant differences in escape probabilities among the different trap models. While the differences in escape probability can explain at least part of the differences in CPUE among the trap models (e.g. high escape rate and low CPUE in red canvas traps), discrepancies between model-specific CPUEs and escape rates suggests that variation in entrance rate also contributes to the differences in CPUE. In general, and in accordance with earlier data on nine-spined stickleback (Pungitius pungitius) trapping, the results suggest that uncoated metallic (Gee-type) traps are superior to the other commonly used minnow trap models in stickleback fisheries. PMID:26685761

  11. Comparison of catch per unit effort among four minnow trap models in the three-spined stickleback (Gasterosteus aculeatus) fishery.

    PubMed

    Budria, Alexandre; DeFaveri, Jacquelin; Merilä, Juha

    2015-12-21

    Minnow traps are commonly used in the stickleback (Gasterostidae) fishery, but the potential differences in catch per unit effort (CPUE) among different minnow trap models are little studied. We compared the CPUE of four different minnow trap models in field experiments conducted with three-spined sticklebacks (Gasterosteus aculeatus). Marked (up to 26 fold) differences in median CPUE among different trap models were observed. Metallic uncoated traps yielded the largest CPUE (2.8 fish/h), followed by metallic black nylon-coated traps (1.3 fish/h). Collapsible canvas traps yielded substantially lower CPUEs (black: 0.7 fish/h; red: 0.1 fish/h) than the metallic traps. Laboratory trials further revealed significant differences in escape probabilities among the different trap models. While the differences in escape probability can explain at least part of the differences in CPUE among the trap models (e.g. high escape rate and low CPUE in red canvas traps), discrepancies between model-specific CPUEs and escape rates suggests that variation in entrance rate also contributes to the differences in CPUE. In general, and in accordance with earlier data on nine-spined stickleback (Pungitius pungitius) trapping, the results suggest that uncoated metallic (Gee-type) traps are superior to the other commonly used minnow trap models in stickleback fisheries.

  12. Determining the Effects of Oiled Sediment on Fish Life Cycle Endpoints using the Sheepshead Minnow (Cyprinodon variegatus)

    EPA Science Inventory

    Determination of long-term effects of exposure to crude oil is critical for ascertaining population-level risk following spill events. A 19-week life-cycle experiment was conducted with the estuarine sheepshead minnow exposed to natural sediment spiked with weathered Louisiana S...

  13. INDUCTION OF ZONA RADIATA PROTEINS AND VITELLOGENINS IN ESTRADIOL AND NONYLPHENOL EXPOSED MALE SHEEPSHEAD MINNOWS (CYPRINODON VARIEGATUS)

    EPA Science Inventory

    Knoebl, Iris, Michael J. Hemmer and Nancy D. Denslow. 2004. Induction of Zona Radiata Proteins and Vitellogenins in Estradiol and Nonylphenol Exposed Male Sheepshead Minnows (Cyprinodon variegatus). Mar. Environ. Res. 58(2-5):547-551. (ERL,GB X1059).

    Several genes normall...

  14. Oxidative stress and immunotoxic effects of bisphenol A on the larvae of rare minnow Gobiocypris rarus.

    PubMed

    Tao, Shiyu; Zhang, Yingying; Yuan, Cong; Gao, Jiancao; Wu, Feili; Wang, Zaizhao

    2016-02-01

    Bisphenol A (BPA), a known endocrine disrupting chemical, is ubiquitous in the aquatic environment and can pose risk to the health of aquatic organisms. Studies on immunotoxicity of BPA in aquatic organisms are limited. In this study, rare minnow (Gobiocypris rarus) larvae were exposed to 1, 225 and 1000μg/L BPA for 7 days. Inflammatory effects of BPA exposure were assessed from the increased production of nitric oxide (NO) and reactive oxygen species (ROS), the change of iNOS mRNA and other TLRs-associated immune gene expression. Our findings provide evidences that different concentrations of BPA can induce a toxic response in fish to produce reactive free radicals which can affect the function of T lymphocytes and decrease the transcription levels of cytokine genes. The excess production of H2O2, induced oxidative stress and suppressed TLR4/NF-κB signaling, leading to immunosuppressive effects in fish larvae. The present results suggest that BPA has the potential to induce oxidative stress accompanied by immunosuppression in rare minnow larvae. PMID:26595511

  15. Toxicity and bioconcentration evaluation of RDX and HMX using sheepshead minnows in water exposures.

    PubMed

    Lotufo, Guilherme R; Gibson, Alfreda B; Yoo, J Leslie

    2010-10-01

    Lethal effects of the explosives RDX and HMX were assessed using ten-day water exposures to juvenile sheepshead minnows (Cyprinodon variegatus). For RDX, maximum mortality occurred during the first two days of exposure with a 10-d median lethal concentration (LC50) of 9.9 mg L(-1). The RDX 10-d median lethal residue (LR50) was 9.6 mg kg(-1) (34.9 μmol kg(-1)) wet weight (ww), the first RDX critical body residue reported for fish. Previous investigations reported that RDX body residues in marine amphipods up to 96 μmol kg(-1) ww and in marine mussels up to 86 μmol kg(-1) ww failed to result in significant mortality. The highest HMX concentration tested, corresponding to its apparent solubility limit in seawater (2.0 mg L(-1)), and the associated mean body residue (3 mg kg(-1) or 14 μmol kg(-1) ww) resulted in no significant mortality for exposed minnows. The mean 10-d bioconcentration factors for RDX (0.6-0.9 L kg(-1)) and HMX (0.3-1.6 L kg(-1)) were typically lower than 1, reflecting the low bioaccumulative potential for these compounds.

  16. Short term chronic and acute toxicity screening of water and sediment using fathead minnows, daphnids, rotifers (Rotox[reg sign]) and light emitting bacteria (Microtox[reg sign]), Ambient Stream Monitoring, summers of 1990 and 1991

    SciTech Connect

    Moses, J.; Wade, D.C.

    1992-07-01

    Toxicological evaluation of water column and sediment samples from six locations in the Ambient Stream Monitoring fixed station network was initiated in 1986 using short-term chronic bioassay methods. Toxicological evaluation of six additional stations was initiated in 1990. Chronic studies were conducted at one of these new stations and acute screening methods were used at all twelve locations now included in the activity. This report provides results from studies conducted during the summers of 1990 and 1991. The 1990--91 studies evaluated toxicity of stream water and porewater extracted from sediments as test media, whereas previous studies evaluated water and sediment elutriate samples.

  17. Short term chronic and acute toxicity screening of water and sediment using fathead minnows, daphnids, rotifers (Rotox{reg_sign}) and light emitting bacteria (Microtox{reg_sign}), Ambient Stream Monitoring, summers of 1990 and 1991

    SciTech Connect

    Moses, J.; Wade, D.C.

    1992-07-01

    Toxicological evaluation of water column and sediment samples from six locations in the Ambient Stream Monitoring fixed station network was initiated in 1986 using short-term chronic bioassay methods. Toxicological evaluation of six additional stations was initiated in 1990. Chronic studies were conducted at one of these new stations and acute screening methods were used at all twelve locations now included in the activity. This report provides results from studies conducted during the summers of 1990 and 1991. The 1990--91 studies evaluated toxicity of stream water and porewater extracted from sediments as test media, whereas previous studies evaluated water and sediment elutriate samples.

  18. Different on the inside: extreme swimbladder sexual dimorphism in the South Asian torrent minnows.

    PubMed

    Conway, Kevin W; Britz, Ralf; Siegel, Dustin S

    2014-07-01

    The swimbladder plays an important role in buoyancy regulation but is typically reduced or even absent in benthic freshwater fishes that inhabit fast flowing water. Here, we document, for the first time, a remarkable example of swimbladder sexual dimorphism in the highly rheophilic South Asian torrent minnows (Psilorhynchus). The male swimbladder is not only much larger than that of the female (up to five times the diameter and up to 98 times the volume in some cases), but is also structurally more complex, with multiple internal septa dividing it into smaller chambers. Males also exhibit a strange organ of unknown function or homology in association with the swimbladder that is absent in females. Extreme sexual dimorphism of non-gonadal internal organs is rare among vertebrates and the swimbladder sexual dimorphisms that we describe for Psilorhynchus are unique among fishes.

  19. Different on the inside: extreme swimbladder sexual dimorphism in the South Asian torrent minnows

    PubMed Central

    Conway, Kevin W.; Britz, Ralf; Siegel, Dustin S.

    2014-01-01

    The swimbladder plays an important role in buoyancy regulation but is typically reduced or even absent in benthic freshwater fishes that inhabit fast flowing water. Here, we document, for the first time, a remarkable example of swimbladder sexual dimorphism in the highly rheophilic South Asian torrent minnows (Psilorhynchus). The male swimbladder is not only much larger than that of the female (up to five times the diameter and up to 98 times the volume in some cases), but is also structurally more complex, with multiple internal septa dividing it into smaller chambers. Males also exhibit a strange organ of unknown function or homology in association with the swimbladder that is absent in females. Extreme sexual dimorphism of non-gonadal internal organs is rare among vertebrates and the swimbladder sexual dimorphisms that we describe for Psilorhynchus are unique among fishes. PMID:25009242

  20. Fish reovirus GCReV-109 VP33 protein elicits protective immunity in rare minnows.

    PubMed

    Liu, Jia; Pei, Chao; Gao, Xiao-chan; Chen, Zhong-yuan; Zhang, Qi-Ya

    2016-03-01

    Grass carp reovirus strain 109 (GCReV-109) was previously isolated from a grass carp (Ctenopharyngodon idellus) with hemorrhagic disease, and its complete genome has been sequenced. However, the infectivity of GCReV-109 has not been studied, and the viral protein VP33, encoded on genome segment S11, had no detectable sequence homology to other known reovirus proteins. In this study, we characterized GCReV-109 infections in vivo and in vitro, as well as the VP33 protein. Infectivity analysis showed that GCReV-109 caused severe hemorrhagic disease and 100% mortality at dilutions up to 10(-4) in rare minnows (Gobiocypris rarus) by 8 days postinfection, but no visible cytopathic effect was observed in GCReV-109-infected subcultured grass carp muscle (GCM) cells. To confirm that GCReV-109 could be propagated in GCM cells, three virus genome segments were detected by RT-PCR, and large numbers of virus particles were observed by transmission electron microscopy in samples from the infected GCM cells. The suspension of GCReV-109-infected GCM cells was pathogenic to rare minnows. VP33 protein was expressed and purified for generation of an anti-VP33 antiserum. In western blot analysis of purified GCReV-109 particles, the antiserum specifically recognized a protein band (approximately 33 kDa). This revealed that VP33 is a major structural protein of GCReV-109 that might have immunogenic properties. The protective efficacy of the anti-VP33 antiserum against GCReV-109 infection was tested. The death of infected fish was delayed and the mortality fell to 10% when fish were treated with the anti-VP33 antiserum, suggesting that it might be useful for the prevention and control of fish reoviral disease. PMID:26615551