| locomotor behavioral response of mosquitofish (gambusia affinis) to subacute mercury stress monitored by video tracking system. | locomotor behavior is commonly affected by contaminants, and the pattern of fish swimming is a highly organized species-specific response. in the current study, we examined the locomotor behavioral response of the mosquitofish, gambusia affinis, which was exposed to a sublethal concentration (lc(5), 20 microg/l) of mercuric chloride (hgcl2) for 28 days and monitored using a computer vision system. the ethovision video tracking system for automation of behavioral studies at regular intervals reve ... | 2007 | 17934926 |
| in vitro assessment of transcriptional activation of the estrogen and androgen receptors of mosquitofish, gambusia affinis affinis. | sex-steroid hormones are essential for normal reproductive activity in both sexes. estrogens are necessary for ovarian differentiation during a critical developmental stage in many vertebrates and promote the growth and differentiation of the female reproductive system. androgens play essential roles in the development and functioning of the vertebrate male reproductive system as well as actively supporting spermatogenesis. importantly, recent studies suggest that androgens and estrogens have im ... | 2007 | 17669586 |
| environmental factors influencing survival of threespine stickleback (gasterosteus aculeatus) in a multipurpose constructed treatment wetland in southern california. | survival of the threespine stickleback, gasterosteus aculeatus, differed among marshes in a demonstration 9.9-ha multipurpose constructed treatment wetland designed to improve the quality of secondary-treated municipal wastewater in southern california. at a mean loading rate of 3.3 kg nh4-n ha(-1) d(-1) (6 kg total n ha(-1) d(-1)), the suitability of the wetland to support a population of sticklebacks was estimated to be low. the development of potentially toxic levels of un-ionized ammonia, pa ... | 2007 | 17633430 |
| a comparative study on the toxic effects of textile dye wastewaters (untreated and treated) on mortality and rbc of a freshwater fish gambusia affinis (baird and gerard). | comparative toxicological studies of textile dye wastewater (untreated and treated) on a freshwater fish, gambusia affinis, revealed a marked reduction in mortality and cytotoxic effects on rbcs, measured as reduction in their counts and percent changes in their shape (poikilocytosis) and variation in their size (anisocytosis)}, after subjecting them to both physicochemical and biological treatments. on comparing the data of mortality and the cytotoxic effects on rbcs, we found poikilocytosis is ... | 2006 | 17405321 |
| simultaneous determination of n7-alkylguanines in dna by isotope-dilution lc-tandem ms coupled with automated solid-phase extraction and its application to a small fish model. | in the present study, we report the development of a sensitive and selective assay based on lc (liquid chromatography)-ms/ms (tandem ms) to simultaneously measure n7-meg (n7-methylguanine) and n7-etg (n7-ethylguanine) in dna hydrolysates. with the use of isotope internal standards (15n5-n7-meg and 15n5-n7-etg) and on-line spe (solid-phase extraction), the detection limit of this method was estimated as 0.42 fmol and 0.17 fmol for n7-meg and n7-etg respectively. the high sensitivity achieved here ... | 2007 | 17134374 |
| a new pseudophyllidean from a freshwater fish, gambusia affinis, in china. | coelobothrium gambusiense n. sp. (bothriocephalidae) was collected and described from the intestine of the freshwater fish gambusia affinis (baird and girard) (poeciliidae) in fujian province, peoples' republic of china. it is the first record of coelobothrium in china. the parasite closely resembles coelobothrium monodi dollfus, 1970, from capoeta damascina (valenciennes, cyprinidae) in iran and coelobothrium oitense kugi and matsuo, 1990, from tribolodon hakonensis (gunther, cyprinidae) in jap ... | 2005 | 17089768 |
| changes in behavior and brain acetylcholinesterase activity in mosquito fish, gambusia affinis in response to the sub-lethal exposure to chlorpyrifos. | sub-lethal studies of chlorpyrifos, o,o-diethyl-o-(3,5,6-trichloro-2-pyridyl) phosphorothioate on mosquito fish, gambusia affinis were carried out in vivo, for 20 days to assess the locomotor behavior in relation to bioaccumulation and interaction with a targeted enzyme, acetylcholinesterase (ache, ec: 3.1.1.7). fish exposed to sub-lethal concentration of 60 microg/l (1/5 of lc 50) were under stress, and reduced their locomotor behavior like distance travelled per unit time (m/min) and swimming ... | 2005 | 16819104 |
| sublethal effects of profenofos on locomotor behavior and gill architecture of the mosquito fish, gambusia affinis. | subacute studies of profenofos on mosquito fish, gambusia affinis, were carried out for 20 days to assess the locomotor behavior and structural integrity of gill in relation to bioaccumulation and targeted enzyme acetylcholinesterase (ache; ec 3.1.1.7). the sublethal concentration of 0.13 mg/l (1/5 of lc50) altered locomotor behavior such as distance traveled and swimming speed in exposed fish. this could be due to inhibition in the activity of acetylcholinesterase and deformities in the primary ... | 2006 | 16777704 |
| use of biomarkers to investigate toxicological effects of produced water treated with conventional and innovative methods. | the aim of this study was to develop and apply a multi-biomarker system to assess the toxicological effects of produced water (pw) from a mediterranean off-shore oil platform. the selected bioindicator organism, mosquitofish (gambusia affinis), was exposed in the laboratory to high concentrations of different pw: pw before treatment (bt), after conventional treatment (act) and after innovative treatment with zeolites in a prototype system (ait). a set of biomarkers (benzo(alpha)pyrene monooxygen ... | 2006 | 16740305 |
| a test of three alternative pathways for consumer regulation of primary productivity. | the pathways linking consumer effects to primary productivity (ppr) are likely to vary among taxa because of species-specific trophic and functional differences. thus, it is necessary to understand the dynamics of consumer-ppr interactions so that effects of species loss on ecosystem function can be addressed from a mechanistic approach. in this study, i used three fish taxa (orangethroat darter, etheostoma spectabile; western mosquitofish, gambusia affinis; and bullhead minnow, pimephales vigil ... | 2006 | 16676207 |
| effect of an acute and chronic toxicity of four commercial detergents on the freshwater fish gambusia affinis baird & gerard. | the toxic effects of four commercial detergents (two washing powders and two cakes) are reported in this paper on behavior, mortality and rbc counts of a freshwater fish gambusia affinis. during acute toxicity studies (96h), surface movements of fish increased markedly for 24h, only at higher concentrations (>10 ppm) of all the four detergents. thereafter, they were lethargic and bottom dwellers similar to those exposed for a period of 30 days in the longterm ecotoxicological studies made on det ... | 2005 | 16649615 |
| sublethal effects of commercial deltamethrin on the structure of the gill, liver and gut tissues of mosquitofish, gambusia affinis: a microscopic study. | the histopathological effects of deltamethrin on the gill, liver and gut tissues of the mosquitofish, gambusia affinis were determined by light microscopy. the fish were exposed to two sublethal concentrations of deltamethrin (0.25-0.50μg/l) for periods of 10, 20 and 30 days. the most common gill changes at all doses of deltamethrin were desquamation and necrosis. besides, epithelial hypertrophy, lifting of the lamellar epithelium, oedema, dilatation of the capillaries primary lamellae, aneurism ... | 2006 | 21783665 |
| accumulation of contaminants in fish from wastewater treatment wetlands. | increasing demands on water resources in arid environments make reclamation and reuse of municipal wastewater an important component of the water budget. treatment wetlands can be an integral part of the water-reuse cycle providing both water-quality enhancement and habitat functions. when used for habitat, the bioaccumulation potential of contaminants in the wastewater is a critical consideration. water and fish samples collected from the tres rios demonstration constructed wetlands near phoeni ... | 2006 | 16468409 |
| quantification of vitellogenin mrna induction in mosquitofish (gambusia affinis) by reverse transcription real-time polymerase chain reaction (rt-pcr). | a method to quantify induction of vitellogenin (vtg) mrna in adult male mosquitofish was developed. male mosquitofish were exposed to 0, 1, 20 and 250 ng l(-1) 17beta-oestradiol (e(2)) for 4 and 8 days in static exposures, and liver vtg mrna and 18s rrna expression were quantified in duplex rt-pcr. liver 18s rrna expression was very consistent among individuals, and there was a highly significant increase in vtg mrna expression after exposure of mosquitofish for just 4 days at 250 ng l(-1) e(2). ... | 2015 | 16308267 |
| sublethal effects of monocrotophos on locomotor behavior and gill architecture of the mosquito fish, gambusia affinis. | subacute studies of monocrotophos [dimethyl (e)-1-methyl-2-(methyl-carbamoyl) vinyl phosphate] on mosquito fish, gambusia affinis, were carried out in vivo for 24 days to assess the locomotor behavior, structural integrity of gill, and targeted enzyme acetylcholinesterase (ache, ec: 3.1.1.7) interactions. monocrotophos (mcp) can be rated as moderately toxic to g. affinis, with a median lethal concentration (lc(50)) of 20.49 +/- 2.45 mgl(-1). the fish exposed to sublethal concentration of lc(10) ... | 2005 | 16194919 |
| incorporation and utilization of multiple forms of vitellogenin and their derivative yolk proteins during vitellogenesis and embryonic development in the mosquitofish, gambusia affinis. | we previously demonstrated the presence of three forms of vitellogenin (vg), two 600 kda vgs (600vg; vga and vgb) and a 400 kda vg (400vg; phosvitinless vg) in plasma from maturing female viviparous mosquitofish, gambusia affinis. for further quantitative elucidation of the accumulation and utilization of the multiple vg-derived yolk proteins, two sandwich enzyme-linked immunosorbent assays (elisa) were developed using antisera against 600vgs and a 400 kda yolk protein (400yp; derived from 400vg ... | 2005 | 15988167 |
| effects of 17alpha-ethynylestradiol on sexual development of male western mosquitofish (gambusia affinis). | juvenile male western mosquitofish (gambusia affinis) were exposed to different concentrations of 17alpha-ethynyl estradiol (ee2) in the diet during the period of sexual maturation. a clear inhibiting influence of ee2 on sexual development was apparent. the proportion of males in each treatment group that failed to complete gonopodial development during the 150-day observation period increased significantly with ee2 concentration. there were significant nonlinear trends toward shorter gonopodia ... | 2013 | 15922671 |
| effects of maternal and embryo characteristics on post-fertilization provisioning in fishes of the genus gambusia. | maternal provisioning of embryos in gambusia (poeciliidae) entails both production of large, yolky eggs and mother-to-embryo transfer of nutrients, the latter of which is readily quantified using injection of radiolabeled nutrients. we assayed patterns of nutrient transfer in broods of 26 gambusia geiseri and 23 gambusia affinis females, using injection of tritiated leucine. we examined maternal and embryo characteristics affecting the instantaneous rate of transfer and characterized the pattern ... | 2005 | 15800747 |
| multiple vitellogenins (vgs) in mosquitofish (gambusia affinis): identification and characterization of three functional vg genes and their circulating and yolk protein products. | the objectives of this study were to characterize multiple forms of vitellogenin (vg) in mosquitofish (gambusia affinis) and to discover the fate of each vg during its processing into product yolk proteins. two vg preparations, with apparent masses of 600 kda (600 vg) and 400 kda (400 vg), were isolated from the plasma of fish treated with estradiol-17beta (e(2)) by various chromatographic procedures. immunological analyses verified the presence of two different vg proteins (600 vga and 600 vgb) ... | 2005 | 15616220 |
| toxic response of endosulfan to breeding and non-breeding female mosquitofish. | to investigate if toxic effects by endosulfan, a commonly used insecticide, are dependent on the breeding condition of an organism, both breeding and non-breeding female western mosquitofish, gambusia affinis, were exposed to 0.1, 0.5, 1 ppb of endosulfan. after a 5-week exposure period, we examined physical factors such as ovary weight and anal fin length in fish of both reproductive conditions and the size of thyroid follicles in non-breeders. breeding female fish exposed to endosulfan did not ... | 2004 | 15529866 |
| shared and unique features of evolutionary diversification. | a fundamental question in evolutionary biology asks whether organisms experiencing similar selective pressures will evolve similar solutions or whether historical contingencies dominate the evolutionary process and yield disparate evolutionary outcomes. it is perhaps most likely that both shared selective forces as well as unique histories play key roles in the course of evolution. consequently, when multiple species face a common environmental gradient, their patterns of divergence might exhibi ... | 2004 | 15478089 |
| androgen dependent development of a modified anal fin, gonopodium, as a model to understand the mechanism of secondary sexual character expression in vertebrates. | male external genitalia show structural variations among species. androgenic hormones are essential for the morphological specification of male type copulatory organs, while little is known about the developmental mechanisms of such secondary sexual characters. western mosquitofish gambusia affinis may offer a clue to the sexual differentiation researches, because they show a prominent masculine sexual character for appendage development, anal fin to gonopodium (gp) transition, and its formation ... | 2004 | 15388345 |
| reproductive status of western mosquitofish inhabiting selenium-contaminated waters in the grassland water district, merced county, california. | this study was implemented to determine if western mosquitofish (gambusia affinis) populations in the grassland water district suffer from impaired reproduction because of seleniferous inflows of agricultural drainwater from the grassland bypass project. during june to july 2001, laboratory trials with pregnant female fish collected from two seleniferous treatment sites exposed to selenium-laden drainwater and two nonseleniferous reference sites yielded fry that averaged > 96% survival at birth. ... | 2004 | 15386130 |
| molecular characterization of contaminant-indicative rapd markers. | this paper describes genetic markers which can be used to study selection and genetic adaptation of organisms to radionuclide and other types of contaminant stress. previous research using the randomly amplified polymorphic dna (rapd) technique has identified several markers which revealed genetic differences between contaminated and reference western mosquitofish (gambusia affinis) populations. experimental evidence suggested that these markers may be associated with loci involved in determinin ... | 2004 | 15344511 |
| complex interactions between native and invasive fish: the simultaneous effects of multiple negative interactions. | we suggest that the ultimate outcome of interactions between native species and invasive species (extinction or coexistence) depends on the number of simultaneous negative interactions (competition and predation), which depends on relative body sizes of the species. multiple simultaneous interactions may constrain the ability of native species to trade fitness components (i.e., reduced growth for reduced risk of predation) causing a spiral to extinction. we found evidence for five types of inter ... | 2004 | 15322899 |
| interspecies differences in dna single strand breaks caused by benzo(a)pyrene and marine environment. | the presence of dna single strand breaks in untreated specimens of selected species, mosquito fish gambusia affinis, painted comber serranus scriba, blue mussel mytilus galloprovincialis, spiny crab maja crispata and sea cucumber holothuria tubulosa as well as in 10 microg/g benzo(a)pyrene (bap) treated mosquito fish, blue mussel and spiny crab was measured, using alkaline filter elution. interspecies differences in alkaline elution profiles were observed and attributed to different lengths of d ... | 2004 | 15288553 |
| effects of the agricultural insecticide lambda-cyhalothrin (warrior) on mosquitofish (gambusia affinis). | because agricultural insecticides have potential to disrupt biological control of mosquitoes, we quantified whether an insecticide used in rice fields causes mortality of mosquitofish. laboratory studies have shown that lambda-cyhalothrin (warrior) is toxic to fish; however, some studies report low field toxicities of pyrethroids to fish because they degrade rapidly and adsorb to soil. we tested whether warrior kills mosquitofish under field conditions. replicated enclosures in a rice field were ... | 2003 | 14710748 |
| [experimental study of larval efficiency of gambusia affinis holbrooki (girard, 1859) (fish-poecilidae)]. | experimental study of efficiency of gambusia affinis holbrooki (girard, 1859) (fish-poecilidae). gambusia affinis is a culiciphage fish which was introduced in tunisia in 1929 to control mosquito larvae. in the present study, we confirm, under laboratory conditions, the good efficacy of gambusia affinis against mosquito larvae. the consumption of larvae decreases with the evolution of larvae instars and increases, for the same instar, in relation with the fish size. in fact, the size of the prey ... | 2006 | 14666756 |
| sex differentiation and pubertal development of gonads in the viviparous mosquitofish, gambusia affinis. | the ontogenetic development of gonads from embryo to adult was observed histologically in the viviparous teleost, gambusia affinis. primordial germ cells (pgcs) appeared in the subendodermal space of the embryo 14 days before birth, and then transferred to the dorsal mesentery to form paired genital ridges 12 days before birth. the pgcs proliferated in the genital ridge, forming gonadal primordia 10 days before birth. all gonadal primordia differentiated to the ovary containing oocytes 2 days be ... | 2003 | 14569146 |
| histopathology of gills in mosquitofish, gambusia affinis after long-term exposure to sublethal concentrations of malathion. | the histopathological effects of malathion, an organophosphate pesticide, on the gill tissues in mosquitofish, gambusia affinis, were determined by light microscope. the fish were exposed to sublethal concentrations (0.01 and 0.02 mg/l) of malathion for 10, 20 and 30 days. histological examination of the gills treated with malathion showed a variety of histopathological effects. the gill lesions included necrosis and desquamation of secondary lamellar epithelium, lifting up of epithelium, intrae ... | 2003 | 12929717 |
| reproductive characteristics of male mosquitofish (gambusia affinis) inhabiting a small southeastern u.s. river receiving treated domestic sewage effluent. | a population of western mosquitofish (gambusia affinis) living below a wastewater treatment plant in the vicinity of birmingham (al, usa) was studied for evidence of exposure to estrogens. mosquitofish are sexually dimorphic live-bearing fish. males have an elongated and modified anal fin, called a gonopodium, used in mating. it has been hypothesized that exposure to estrogens and/or anti-androgens in treated wastewater might inhibit the androgen-dependent development of the gonopodium. the popu ... | 2002 | 12109740 |
| toxicological effects of the herbicide oxyfluorfen on acetylcholinesterase in two fish species: oreochromis niloticus and gambusia affinis. | the alterations of the ache activity in the brains of two fresh water fishes; oreochromis niloticus and gambusia affinis were measured after exposure to acute, sub-acute and chronic concentrations from the widely used herbicide; oxyfluorfen. bioassays were conducted under controlled laboratory conditions. the used concentrations were acute: lc50 for 6 days, sub-acute 1/3 lc50 for 15 days and chronic 1/10 lc50 for 30 days. the obtained results showed marked inhibitory effects of the herbicide on ... | 2002 | 12046652 |
| population genetic structure of the western mosquitofish, gambusia affinis, in a highly channelized portion of the san antonio river in san antonio, tx. | population genetic assessments were performed on populations of the mosquitofish, gambusia affinis, sampled at seven sites along a 10 km reach of the upper san antonio river in san antonio, tx. mosquitofish populations were sampled from the downtown area, known as the "riverwalk", where the river is concrete lined, deeply pooled, and receives heavy tour boat traffic. populations were also sampled from sites upstream and downstream from the riverwalk. allozyme electrophoresis was performed on app ... | 2001 | 11501432 |
| gonopodium development in normal male and 11-ketotestosterone-treated female mosquitofish (gambusia affinis): a quantitative study using computer image analysis. | mature male mosquitofish possess a highly modified anal fin called a gonopodium that develops from an unmodified female-like anal fin under the influence of endogenous androgens at sexual maturity. although females do not normally develop gonopodia, their anal fins can be induced to develop into gonopodium-like structures by the administration of androgens. we used computer image analysis techniques to quantify the morphological changes in the anal fins of normal male and female mosquitofish dur ... | 2001 | 11482943 |
| the histopathological effects of thiodan on the liver and gut of mosquitofish, gambusia affinis. | thiodan (33.7% endosulfan), a polychlorinated cyclodiene insecticide, was evaluated for its histopathological effects on mosquitofish, gambusia affinis, by light microscopy. fish were exposed to doses of 0.00 (control), 1.00, 2.50, and 5.00 microg/l on days 7, 14, 21, and 30. no histopathological effects were apparent at control group. the histopathological alterations were characterized as oedema, degeneration, accumulation of lymphocytes in the lamina propria, disintegration of villuses, pycno ... | 2001 | 11281257 |
| mosquitofish (gambusia affinis) vitellogenin: identification, purification, and immunoassay. | vitellogenin is a phospholipoglycoprotein precursor of egg yolk. in mature female fish, vitellogenin is synthesized and secreted by the liver in response to circulating estrogens. vitellogenin is normally undetectable in the blood of male fish, but can be induced by exposure to compounds possessing estrogenic activity. thus, the presence of vitellogenin in blood of male fish can serve as a useful biomarker for assessing previous exposure to estrogenic compounds. in the present study, we report i ... | 2001 | 11239836 |
| relationship between allozyme genotype and sensitivity to stressors in the western mosquitofish gambusia affinis detected for elevated temperature but not mercury. | previous studies with gambusia holbrooki have found associations of allozyme genotype with tolerance to metals, pesticides, heat, and salinity. to examine the generality of these relationships, we looked for similar associations of mercury and heat tolerance with allozyme genotype at the gpi-2, mdh-1 and mdh-2 loci in its sister species gambusia affinis. this was done to assess if the loci themselves or closely linked loci were associated with mercury tolerance, because weaker linkage associatio ... | 2001 | 11239682 |
| discrimination between several diterpenoid compounds in feeding by gambusia affinis. | the alcyonacean soft coral sinularia flexibilis quoy and gaimard produces a number of bioactive complementary (secondary) metabolites. the ability of three of these diterpenes - flexibilide, sinulariolide and dihydroflexibilide - to elicit differential discriminatory feeding behavior in gambusia affinis was assessed in a feeding deterrence study. terpene-impregnated fish flakes were offered to fish trained to feed on such food, and their responses (acceptance, rejection, avoidance, or no respons ... | 2001 | 11166674 |
| experimental evaluation of the usefulness of microsatellite dna for detecting demographic bottlenecks. | evolutionary and conservation biologists often use molecular markers to evaluate whether populations have experienced demographic bottlenecks that resulted in a loss of genetic variation. we evaluated the utility of microsatellites for detection of recent, severe bottlenecks and compared the amounts of genetic diversity lost in bottlenecks of different sizes. in experimental mesocosms, we established replicate populations by releasing 1, 2, 4 or 8 pairs of the western mosquitofish, gambusia affi ... | 2000 | 11050547 |
| a model for non-specific toxicity with aquatic organisms over relatively long periods of exposure time. | experimental data have shown that the internal lethal concentrations of halobenzenes for aquatic organisms decreased with exposure time. in this paper, a model based on the concept of life expectancy reduction was developed to describe this relationship. the model was verified with experimental data for fish (gambusia affinis) and juvenile crab (porturius pelagicus(l)). it is proposed that long term non-specific toxicity can be measured as the reduction of the life expectancy of the exposed orga ... | 1999 | 10903121 |
| scalarane and homoscalarane compounds from the nudibranchs glossodoris sedna and glossodoris dalli: chemical and biological properties. | a series of homoscalarane and scalarane compounds (2-7) have been isolated from two distinct species of pacific glossodoris nudibranchs. the structure and elucidation of the relative stereochemistry of the new metabolites 2 and 3 were obtained by spectroscopic methods. compound 2 was ichthyotoxic at 0.1 ppm against gambusia affinis and showed moderate activity (ic(50) 18 microm) to inhibit mammalian phospholipase a(2). | 2000 | 10785432 |
| environmental regulation of annual reproductive cycle in the mosquitofish, gambusia affinis. | to clarify the environmental factors regulating the annual reproductive cycle of the female mosquitofish, gambusia affinis, a viviparous teleost, histological changes of the ovary in natural population, and laboratory experiments were examined. the results, extending over two years, suggested that ovarian recrudescence is initiated by the rise in temperature during spring and that ovarian regression is caused by the shorter daylength during late summer. the first rearing experiments using four p ... | 2000 | 10617862 |
| comparative efficacy of the threespine stickleback (gasterosteus aculeatus) and the mosquitofish (gambusia affinis) for mosquito control. | the effectiveness of the threespine stickleback as a mosquito control agent was compared to that of the mosquitofish in 28-m2 earthen ponds during 26-wk experiments where the 2 fish were stocked alone and together. relative to ponds without fish, the stickleback was not effective for controlling larval mosquito populations; however, sticklebacks reduced the abundance of culex pupae. mosquitofish provided significant levels of control whether stocked alone or concurrently with the stickleback. as ... | 1999 | 10480131 |
| morphological and reproductive characteristics of male mosquitofish (gambusia affinis holbrooki) inhabiting sewage-contaminated waters in new south wales, australia. | the potential effects of exposure of fish to reproductive endocrine disruptors (reds) is of major concern. this study reports on the effects of sewage effluent exposure on morphology of male mosquitofish (gambusia a. holbrooki) in a tributary of the hawksbury-nepean river system in new south wales, australia. the growth and development of the modified anal fin (the gonopodium, gp) is a secondary sexual characteristic in males, forms under the influence of testosterone, and is critical for sperm ... | 1999 | 10047598 |
| polymorphic microsatellite markers in the western mosquitofish, gambusia affinis. | | 1999 | 9919704 |
| a mechanism for anterior transposition of the anal fin and its appendicular support in the western mosquitofish, gambusia affinis affinis | the interosseal and suspensory ligaments of the axial and appendicular skeleton of the western mosquitofish, gambusia affinis affinis were investigated in whole-mounted late embryonic and adult female and male g. a. affinis stained with alcian blue and alizarin red s, cleared, and viewed using differential interference contrast. the interosseal and suspensory ligaments of late embryonic female g. a. affinis are reduced prior to sexual differentiation and continue reduced in adult females. howeve ... | 1998 | 9873137 |
| parasitological data as monitors of environmental health. | when an appropriate fish host is selected, analysis of its parasites offers a useful, reliable, economical, telescoped indication or monitor of environmental health. the value of that information increases when corroborated by another non-parasitological technique. the analysis of parasites is not necessarily simple because not all hosts serve as good models and because the number of species, presence of specific species, intensity of infections, life histories of species, location of species in ... | 1997 | 9802064 |
| internal lethal concentration and internal lethal volume fraction of chlorobenzenes in mosquito fish (gambusia affinis). | the internal lethal concentration (ilc) and internal lethal volume fraction (ilvf) of a series of chlorobenzenes with mosquito fish (gambusia affinis) were measured by a semistatic test approach in closed jars. their variation with exposure times were also investigated with different aqueous chemical concentrations and different exposure periods, the measured ilc values on wet weight and lipid weight bases ranged from 3-12 mmol kg-1 and 46-208 mmol kg-1 lipid, respectively. measured ilvf values ... | 1998 | 9717246 |
| short-term effects of bolero on the gill apparatus of a small number of mosquitofish (gambusia affinis). | | 1998 | 9702371 |
| effects of halobenzenes on growth rate of fish (gambusia affinis). | the growth rate reduction of mosquito fish (gambusia affinis) fry was investigated with a range of sublethal exposure levels of four halobenzenes for 42 days. these compounds were found to produce growth rate reduction in mosquito fish fry at concentrations as low as 0.30, 0.18, 0.025, and 0.010 mumol liter-1 for 1,4-dibromobenzene, 1,2,3-trichlorobenzene, 1,2,4-tribomobenzene, and pentachlorobenzene, respectively. the aqueous exposure concentrations causing growth rate reduction of 50 and 10% ( ... | 1998 | 9515084 |
| mosquito control with gambusia affinis. | | 1997 | 9383776 |
| diurnal fluctuations in toxicity in two fish species: gambusia affinis and notropis ludibundis. | | 1997 | 9256395 |
| opsin sequences of the rod visual pigments in two species of poeciliid fish | the rod opsin sequences from gambusia affinis holbrooki and poecilia reticulata were cloned and sequenced. the opsin sequences were found to be 96·8% identical, reflecting the similarity of the rod visual pigment absorbances in these two poeciliid fish. | 1997 | 9236103 |
| internal lethal concentrations of halobenzenes with fish (gambusia affinis). | the internal lethal concentrations is a potential measure of toxicity which could be usefully applied in environmental toxicology and risk assessment. using halobenzenes, which are common environmental contaminants, and represented test compounds, experiments were conducted in aquaria with the mosquitofish (gambusia affinis). the average internal lethal concentration (ilc50) for four representative halohydrocarbons, 1,4-dibb, 1,2,3-tricb, 1,2,4-tribb, and pentacb, were consistent with those prev ... | 1997 | 9212338 |
| mosquito control with gambusia affinis. | | 1997 | 9152886 |
| sex differences in endogenous retinoid release in the post-embryonic spinal cord of the western mosquitofish, gambusia affinis affinis. | in this study we have shown sex differences in endogenous retinoic acid synthesis and retinaldehyde dehydrogenase activity in the post-embryonic spinal cords of immature female and male g. a. affinis. the f9 reporter cell assay and the zymography bioassay showed that the endogenous retinoic acid levels correlated with the levels of the endogenous enzyme(s) responsible for retinoic acid synthesis. these data also showed that both the endogenous retinoic acid levels and the enzyme(s) were higher i ... | 1997 | 9059611 |
| organizational-activational concept revisited: sexual differentiation in an atherinomorph teleost. | because of its numerous sexually dimorphic characters, the western mosquitofish gambusia affinis affinis is an excellent vertebrate system for addressing questions concerning sexual differentiation. in this review, the actions and limits of gonadal sex steroids, specifically testosterone, on the development of the sexually dimorphic anal fin and its axial and appendicular support are described. data from our laboratory show that the critical period in this species for the anterior transposition ... | 1996 | 9047280 |
| adverse assessments of gambusia affinis: an alternate view for mosquito control practitioners. | adverse opinions on the introduction of gambusia affinis for the control of larval mosquitoes are reviewed. the sources span a period of some 59 years and come from a variety of sources. the principal opposition to the introduction of g. affinis comes from ichthyologists, although some mosquito researchers have expressed concerns about the environmental impact of placing the fish in habitats to which it is not native. questions concerning the appropriateness of using the fish are presented. | 1996 | 8827587 |
| time course of inhibition of cholinesterase and aliesterase activities, and nonprotein sulfhydryl levels following exposure to organophosphorus insecticides in mosquitofish (gambusia affinis). | cholinesterase (che) in brain and muscle was quickly inhibited during a 48-hr in vivo exposure to chlorpyrifos (0.1 ppm), parathion (0.15 ppm), and methyl parathion (8 ppm) in mosquitofish (gambusia affinis). che remained inhibited during a 96-hr nonexposure period. brain che reached peak inhibition by 12 hr after exposure to parathion and chlorpyrifos and by 4 hr after exposure to methyl parathion. all insecticides caused greater than 70% che inhibition by 4 hr in muscle. there was no recovery ... | 1996 | 8742317 |
| variation in heat shock proteins within tropical and desert species of poeciliid fishes. | the 70-kilodalton heat shock protein (hsp70) family of molecular chaperones, which contains both stress-inducible and normally abundant constitutive members, is highly conserved across distantly related taxa. analysis of this protein family in individuals from an outbred population of tropical topminnows, poeciliopsis gracilis, showed that while constitutive hsp70 family members showed no variation in protein isoforms, inducibly synthesized hsp70 was polymorphic. several species of poeciliopsis ... | 1995 | 8524039 |
| the first record of fish as paratenic hosts of falcaustra spp. (nematoda: kathlaniidae). | two types of third-stage nematode larvae (most of which were encapsulated) were collected from the abdominal cavity and liver of the freshwater fishes etheostoma fonticola, etheostoma lepidotum, cichlasoma cyanoguttatum, lepomis auritus, lepomis sp., and gambusia affinis in texas and are referred to the genus falcaustra. this is the first record of falcaustra larvae from fishes, and their presence may reflect the importance of fishes as paratenic hosts of turtle parasites in this genus. | 1995 | 7472886 |
| intermediate filaments in the testis of the teleost mosquito fish gambusia affinis holbrooki: a light and electron microscope immunocytochemical study and western blotting analysis. | a light and electron microscope immunocytochemical study and western blotting analysis has been performed on intermediate filaments (vimentin, desmin and cytokeratins) in the testis of the teleost fish gambusia affinis holbrooki. an immunoreaction to vimentin was observed in the epithelium of the efferent ducts, testicular canal and their surrounding peritubular cells. positive vimentin immunostaining was also observed in the cells located around seminiferous tubules (boundary cells), leydig cel ... | 1995 | 7635766 |
| cytoskeleton in sertoli cells of the mosquito fish (gambusia affinis holbrooki). | there is little information about the distribution of cytoskeletal components in the testes of teleost fish. the aim of this paper was to know the distribution of some major cytoskeletal proteins (tubulin, actin, vimentin, desmin, and cytokeratins) in the sertoli cells of gambusia affinis holbrooki and in their efferent duct epithelial cells which are possibly originated from the sertoli cells. | 1995 | 7710138 |
| cytonuclear genetics of experimental fish hybrid zones inside biosphere 2. | two species of mosquitofish (family poeciliidae) known to hybridize in nature were introduced into freshwater habitats inside biosphere 2, and their population genetics were monitored after 2 years. within four to six generations, nuclear and cytoplasmic markers characteristic of gambusia holbrooki had risen greatly in frequency, although some gambusia affinis alleles and haplotypes were retained primarily in recombinant genotypes, indicative of introgressive hybridization. the temporal cytonucl ... | 1994 | 8197186 |
| the distribution of corticotropin-releasing factor immunoreactive neurons and nerve fibres in the brain of gambusia affinis and salmo trutta. | the study was carried out on the distribution of neurons and fibres which contain the corticotropin releasing factor-like (crf) immunoreactivity in the encephalon of two species of teleosts, gambusia affinis and salmo trutta. the peroxidase-antiperoxidase (pap) immunocytochemical technique was employed. the present study has shown differences between both species. in gambusia affinis, positive neurons were observed in the area ventralis telencephali pars lateralis (vlt), in the nucleus praeoptic ... | 1994 | 8075480 |
| hepatocarcinogenesis in western mosquitofish (gambusia affinis) exposed to methylazoxymethanol acetate. | to assess the potential of western mosquitofish (gambusia affinis) for the detection of environmental carcinogens, laboratory-reared specimens were exposed to methylazoxymethanol acetate 10 mg per 1 for 2 h and then examined periodically for the onset of neoplastic lesions. approximately 33 per cent of the exposed fish developed liver neoplasms within 25 weeks of exposure and 52 per cent within 40 weeks. the lesions were mostly hepatocellular carcinomas and cholangiocarcinomas. no neoplastic les ... | 1994 | 8040379 |
| development of the anal fin appendicular support in the western mosquitofish, gambusia affinis affinis (baird and girard, 1854): a reinvestigation and reinterpretation. | development of the sexually dimorphic anal fin appendicular support of an internal fertilizing bony fish gambusia affinis affinis was investigated by staining whole-mounted embryos, immature, and adult female and male g. a. affinis with alizarin red s and alcian blue. the tissue was examined histologically to assess development of the amphicelous centrum and to verify specificity of the stains. our data confirm earlier claims about the development of the male and female characteristics in this s ... | 1994 | 7879590 |
| biocontrol efficacy of gerris (a) spinolae, laccotrephes griseus and gambusia affinis on larval mosquitoes. | predation experiments using gerris (a) spinolae, laccotrephes griseus and gambusia affinis were conducted against iv stage culicine larvae with varying prey densities. ranking of individual predatory efficiency showed the sequence: large gambusia > medium gambusia > small gambusia > female laccotrephes > male laccotrephes > gerris. predation under coexistence reveals the significance of predatory efficiency of different predator combinations with reference to prey density and exposure period. | 1993 | 8034107 |
| use of an indigenous fish species, fundulus zebrinus, in a mosquito abatement program: a field comparison with the mosquitofish, gambusia affinis. | studies were conducted relating mosquito production in small ponds to presence or absence of larvivorous fishes. data collected showed that native killifish and introduced mosquitofish controlled mosquito larvae at the same level and support the use of indigenous fish species in mosquito abatement programs. | 1992 | 1357089 |
| distribution of neuropeptide y-like immunoreactivity in the brain of salmo salar and gambusia affinis. | through the immunohistochemical pap technique, the distribution of immune positive neurons and fibres for an antibody anti-npy in the encephalon of salmon fixed in bouin have been located and studied. npy-positive neurons are found forming three important nuclei: in the ventrolateral telencephalon; in the tegmentum mesencephali; and in the locus coeruleus. neurons in the optic tectum, in the thalamic region and a few in the preoptic recess have also been located. the fibres were found throughout ... | 1992 | 1504458 |
| ichthyotoxic diterpenoids from the cantabrian nudibranch chromodoris luteorosea. | five spongian diterpenoids 2, 3, 6-8, previously found in sponges and nudibranchs from very distinct geographical areas, have been isolated from the cantabrian nudibranch chromodoris luteorosea. the terpenoids are mainly localized along the border of the mantle of the mollusk. all the diterpenoids are toxic to gambusia affinis. | 1992 | 1593284 |
| the history of malaria control in the southwest pacific region, with particular reference to papua new guinea and the solomon islands. | a number of phases in the history of malaria control in the southwest pacific region can be recognized. during the first phase (1898-1923) it was known that anopheline mosquitoes carried malaria, but as yet the identity of the local vectors had not been established. the incrimination of the vectors in 1923 gave a sound basis for control, which remained largely urban in location except for the distribution of the larvivorous fish gambusia affinis. the exigencies of the pacific war and the presenc ... | 1992 | 1566607 |
| enhancing the efficacy of gambusia affinis to control mosquito breeding in ponds. | | 1992 | 1459302 |
| some observations on the fine structure of the sensory cells in the neuromasts (ordinary lateral line) of the teleost gambusia affinis. | the structural and ultrastructural features of the sensory cells in the neuromasts of g. affinis were studied. these pear-shaped cels present a tuft of sensory hairs rising from the apex and a highly dense cytoplasm with multivesicular bodies, dyctiosomes, granular and smooth endoplasmic reticulum and numerous mitochondria. large round granular dense bodies of an unknown nature can be observed inside and outside the nucleus. a great number of vesicles are present at the base of the cells, some o ... | 1992 | 1447513 |
| acute toxicity of mosquitocidal compounds to young mosquitofish, gambusia affinis. | toxicity of florida mosquito larvicides and adulticides to 3-5 day old gambusia affinis was determined in the laboratory. after 24-h exposure, the larvicides, temephos, fenoxycarb and petroleum distillates had lc50 values of 5.60, 1.05 and 593.4 ppm, respectively. after 24 h the adulticides resmethrin, fenthion, naled and malathion had lc50 values of 0.007, 2.94, 3.50 and 12.68 ppm, respectively. the only compound toxic to young mosquitofish at maximum field application rates was resmethrin. how ... | 1991 | 1716659 |
| seasonal occurrence of lernaea cyprinacea on fishes in belews lake, north carolina. | prevalence, abundance, and mean intensity of lernaea cyprinacea were monitored on 3 species of fishes from june 1984 through august 1986 in belews lake, north carolina. copepods were observed parasitizing fishes only during summer, when water temperatures exceeded 25 c. infection levels in mosquitofish (gambusia affinis) and red shiners (notropis lutrensis) were very low, but they were much higher in fathead minnows (pimephales promelas). infection levels do not appear to be related to the size ... | 1991 | 2010869 |
| effects of diet on amylase expression in the mosquitofish. | diets high in various carbohydrates were fed to mosquitofish,gambusia affinis holbrooki, to determine the effects on amylase expression. both amylase activity and amount of amylase protein were used as measures of amylase expression. fish were fed for 21 days in one experiment, seven days in a second experiment and 24 h in a third. the first experiment compared responses of fish fed on a high-starch diet relative to a control diet. the second and third experiments compared responses on four diet ... | 1991 | 24214607 |
| ultrastructural study of the cellular types in the pineal organ of gambusia affinis (teleost). | the pineal organ of gambusia affinis was studied via light and electron microscopy. the cell types studied included photoreceptor cells, supporting cells, and a third cell type. the photoreceptor cells, which appear to form clusters, are divided into four regions: outer segment, inner segment, cell soma, and synaptic pedicle. synaptic ribbons are commonly observed in the synaptic pedicle. the supporting cells separate the photoreceptor cells from the thick basal lamina that surrounds the entire ... | 1990 | 2371966 |
| mosquito control in wastewater: a controlled and quantitative comparison of pupfish (cyprinodon nevadensis amargosae), mosquitofish (gambusia affinis) and guppies (poecilia reticulata) in sago pondweed marshes. | we compared the abilities of pupfish, mosquitofish and guppies to control mosquitoes in wastewater marshes. all species of fish reduced mosquito emergence. when fish population densities were similar, fish reduced emergence to similar levels. as experiments progressed, guppies developed greater population densities and provided better mosquito control than mosquitofish, which developed greater densities and better control than pupfish. fish also reduced numbers of zooplankton, and guppies increa ... | 1990 | 1973447 |
| tissue-specific distribution of amylase in the mosquitofish (gambusia affinis holbrooki). | tissue-specific expression of alpha-amylase (e.c.3.2.1; α 1,4-glucan-4-glucano-hydrolase) was studied in the mosquitofish (gambusia affinis holbrooki). gut activity patterns, immunohistochemical distribution in the hepatopancreas and tissue-specific activities and amount of amylase protein were characterized. in the gut, activity was observed all along the gut and no variation in this pattern was observed in individuals from two natural populations. in the hepatopancreas, amylase is found in pan ... | 1990 | 24221951 |
| size-dependence of mercury (ii) accumulation kinetics in the mosquitofish, gambusia affinis (baird and girard). | size-dependence of mercury (ii) accumulation from water by the mosquitofish, gambusia affinis was assessed under controlled laboratory conditions. uptake rates were higher for smaller fish than for larger fish. mean (+/- s.d.) uptake rate for mosquitofish exposed to 0.24 micrograms/l of hg was 0.32 +/- 0.15 micrograms/g dry wt/day. uptake rate constants were similar for the hg (ii) and elemental hg as reported elsewhere. both inorganic species (hg(ii) and elemental hg) were accumulated faster th ... | 1989 | 2619322 |
| laboratory induction of intersexuality in the mosquitofish, gambusia affinis, using paper mill effluent. | | 1989 | 2804401 |
| role of the brain t-butylbicyclophosphorothionate receptor in vertebrate resistance to endrin, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane and cypermethrin. | certain populations of mosquitofish (gambusia affinis) are highly resistant to endrin (42-fold), but are not cross-resistant to cypermethrin. these populations show relatively low levels of resistance (2-fold) to 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (ddt) and t-butylbicyclophosphorothionate (tbps). studies comparing specific [35s]tbps binding to brain membrane preparations from resistant and susceptible fish indicate a reduced binding capacity for tbps in membranes from resistant fish. ... | 1989 | 2540310 |
| effects of various factors on the efficiency of minnow traps to sample mosquitofish (gambusia affinis) and green sunfish (lepomis cyanellus) populations. | the effects of various factors on the efficiency of the gee minnow trap to sample populations of mosquitofish, gambusia affinis, in both rice field enclosures and a laboratory tank were assessed. immature green sunfish, lepomis cyanellus, were assessed in the laboratory tank only. trap efficiency (percent catch) was greater for larger mosquitofish [greater than or equal to 35 mm total length (tl)] than for smaller mosquitofish. immature green sunfish (25-40 mm tl) were caught at higher rates tha ... | 1989 | 2708987 |
| membrane formations in the pineal cells of the teleost gambusia affinis. | highly organized membrane formations in the cytoplasm of photoreceptor and supporting cells of the pineal organ of gambusia affinis are described. these membranous structures show different characteristics depending on the cell type where they are located. some of the morphological characteristics of these membranous formations are similar to those of myeloid bodies, but their presence in the photoreceptor cells raises some doubt about their being myeloid bodies. the three-dimensional interpreta ... | 1989 | 2600758 |
| toxicity of selected insecticides (thiodan, security, spartan, and sevin) to mosquitofish, gambusia affinis. | | 1988 | 3133001 |
| vertebrate cyclodiene insecticide resistance: role of gamma-aminobutyric acid and diazepam binding sites. | certain populations of the mosquitofish (gambusia affinis) are highly resistant to cyclodiene and cyclodiene-type insecticides that competitively interact with the picrotoxinin binding site of the gamma-aminobutyric acid (gaba) receptor-ionophore complex in the central nervous system. resistance involves a reduction in affinity of the picrotoxinin binding site. the present study reports that gaba receptor binding is increased in resistant brain membranes compared to membranes from susceptible fi ... | 1988 | 2853620 |
| the amylase gene-enzyme system of fishes. i. developmental expression of amylase in the mosquitofish. | the objective of this study is to examine the effects of developmental stage on amylase expression in the mosquitofish (gambusia affinis holbrooki, poeciliidae). expression was characterized in terms of amylase activity and amount of amylase protein in five developmental stages: early, mid, and late embryos, 5-day-old juveniles, and adults. two measures of activity were used: a starch-iodine assay, which measures the change in substrate, and the dinitrosalicyclic acid (dnsa) assay, which measure ... | 1988 | 2450960 |
| defensive strategies of soft corals (coelenterata: octocorallia) of the great barrier reef : iii. the relationship between ichthyotoxicity and morphology. | the relationship between ichthyotoxicity and predation-related defensive functional morphology was examined in alcyonacean soft corals of the central and northern regions of the great barrier reef (gbr), australia. approximately 170 specimens were assessed encompassing a number of genera within three families: 1) the alcyoniidae (lobophytum, sarcophytum, sinularia, cladiella, parerythropodium, and alcyonium); 2) neptheidae (lemnalia, paralemnalia, capnella, lithophyton, nephthea, dendronephthya, ... | 1987 | 28310420 |
| pathology of pentastomid infections (sebekia mississippiensis) in fish. | differential pathogenesis was observed in two species of fish naturally infected with the pentastome sebekia mississippiensis. mosquitofish (gambusia affinis) showed a mild inflammatory response to developing nymphs, whereas swordtails (xiphophorus helleri) had an extensive granulomatous inflammatory reaction with accompanying hemorrhage, myositis, and myodegeneration. this suggested that certain species of tropical fish reared in the southeastern united states may be at risk to potentially harm ... | 1987 | 3682099 |
| fat cycling in the mosquitofish (gambusia affinis): fat storage as a reproductive adaptation. | we argue, based on reviewed literature covering reptiles, amphibians, birds, and fish, that fat storage may represent a life history adaptation because it enables an organism to shift in time when resources are allocated to reproduction. we applied these arguments to fat and population cycles in three populations of the mosquito fish, gambusia affinis. for males, there appeared to be a constant size at maturation during the reproductive season. mature males became scarce late in the summer. at t ... | 1987 | 28311522 |
| relation of length and sex to selenium concentrations in mosquitofish. | analysis of mosquitofish, gambusia affinis, has proven useful for monitoring contaminant levels in aquatic biota; however, the small size of this species often requires the compositing of several fish to provide sufficient biomass for selenium analysis. such composites have usually been obtained without considering the length and sex of the individual fish. the present study found significant differences in mean lengths and sex ratios of mosquitofish sampled with small-mesh dip nets from five si ... | 1987 | 15092705 |
| monogenic inheritance of cyclodiene insecticide resistance in mosquitofish, gambusia affinis. | certain populations of the mosquitofish, gambusia affinis, developed high levels of resistance to endrin and other cyclodiene insecticides as a result of inadvertent exposure to agricultural sprays. genetic crossing studies show that endrin resistance is inherited as a single, autosomal, intermediate gene. | 1986 | 3755403 |
| efficacy of fish larvivore, gambusia affinis for the control of mosquito breeding in wells in semi-urban areas near delhi. | | 1986 | 2879863 |
| intraventricular blood vessels of the hypothalamus of salmo gairdneri and gambusia affinis. | the ultrastructure of the hypothalamic intraventricular blood vessels is studied in two fish: salmo gairdneri, a primitive teleost and gambusia affinis, a modern teleost. morphological differences found between vessels belonging to the lateral and medial recesses in salmo are described as well as contrasted with those of gambusia. the endothelial cells are joined by elaborate tight junctions in both teleosts and also by desmosomes in gambusia. these vessels are continuous capillaries with pericy ... | 1986 | 3954061 |
| experimental mass-rearing of the mosquitofish, gambusia affinis. | a solar heated, closed-system, intensive culture facility for mass-rearing of gambusia affinis is described. the results of fry production experiments and short-term growth rate experiments are presented and interpreted to indicate that operational fish production at or below the goal of $16.50/kg will not be easily reached. | 1985 | 3880247 |
| relative susceptibility of common vector mosquito larvae and larvivorous fish, gambusia affinis and poecilia reticulata to three new insecticides. | | 1985 | 2872250 |
| short-term interactions between ddt and endrin accumulation and elimination in mosquitofish (gambusia affinis). | | 1985 | 3839122 |
| the environmental impacts of four insecticides on non-target organisms in the gezira irrigation scheme canals of sudan. | the toxic effects of the insecticides endosulfan, decamethrin, dimethoate and dursban on the aquatic fauna of some of the gezira irrigation canals were studied. the animal groups selected were fishes, arthropods and snails. endosulfan was found to be highly toxic, particularly to gambusia affinis, under field and laboratory conditions. all animals proved to be less sensitive to decamethrin in the field probably because this insecticide reacted with the organic matter and hence its toxicity was r ... | 1985 | 2411946 |
| density estimation and population growth of mosquitofish (gambusia affinis) in rice fields. | mark-release-recapture estimation of population density was performed with mosquitofish in a rice field habitat. regression analysis showed a relationship between absolute density and mean number of fish per trap. trap counts were converted to density estimates with data from several fields and growth curves were calculated to describe seasonal growth of mosquitofish populations at three different initial stocking rates. the calculated curves showed a good correspondence to field populations of ... | 1985 | 2906659 |