Sample records for toxorhynchites rutilus rutilus

  1. Interactions between the roach, Rutilus rutilus , and waterfowl populations of Lough Neagh, Northern Ireland

    Microsoft Academic Search

    Ian J. Winfield; Denise K. Winfield; Catherine M. Tobin

    1992-01-01

    Synopsis Following the introduction of roach, Rutilus rutilus, to a large eutrophic lake in ca. 1973, a subsequent increase in the abundance of this cyprinid through the 1970s was accompanied by a decline in the numbers of one of the lake&s most abundant overwintering waterfowl, the tufted duck, Aythya fuligula, and an increase in overwintering piscivorous great crested grebes, Podiceps

  2. Effects of habitat and season on competitive interactions between roach ( Rutilus rutilus ) and perch ( Perca fluviatilis )

    Microsoft Academic Search

    L. Persson

    1987-01-01

    The competitive interactions between two distantly related fish species, roach (Rutilus rutilus) and perch (Perca fluviatilis), were studied in enclosures in two habitats. In the open water habitat dominated by small planktonic prey perch grew more slowly and altered its diet from zooplankton to benthic macroinvertebrates when in the presence of roach. No effect, however, of perch on roach was

  3. Acclimatization of roach, Rutilus rutilus (L. ), to toxic components of kraft pulp mill effluents

    Microsoft Academic Search

    A. Oikari; J. Kukkonen

    1988-01-01

    Roach (Rutilus rutilus) were exposed, along with their appropriate controls, to a simulated bleached kraft mill effluent (KME-Sa + CP) first for 38 days at a concentration of 0.035 X LC50 and then for 14 days at 0.07 X LC50. During the experiment, their tolerances to KME-Sa + CP were tested five times by measuring the 48-hr LC50 values. In

  4. Interactive effects of season and temperature on enzyme activities, tissue and whole animal respiration in roach, Rutilus rutilus

    Microsoft Academic Search

    Franz Koch; Wolfgang Wieser; Harald Niederstätter

    1992-01-01

    Synopsis This paper reviews investigations on the ecophysiology of a population of roach, Rutilus rutilus, from a subalpine oligotrophic lake in the Austrian Tirol. Metabolic responses to season and temperature were studied in whole animals, tissues and selected enzymes. The exponent of the relationship between body mass and three levels of the metabolic rate of acclimated fish was 0.82 ±

  5. Acclimatization of roach, Rutilus rutilus (L. ), to toxic components of kraft pulp mill effluents

    SciTech Connect

    Oikari, A.; Kukkonen, J.

    1988-06-01

    Roach (Rutilus rutilus) were exposed, along with their appropriate controls, to a simulated bleached kraft mill effluent (KME-Sa + CP) first for 38 days at a concentration of 0.035 X LC50 and then for 14 days at 0.07 X LC50. During the experiment, their tolerances to KME-Sa + CP were tested five times by measuring the 48-hr LC50 values. In addition, the growth of roach was monitored. At the end of the exposure, accumulation of (/sup 14/C)pentachlorophenol in various parts of the fish (total PCP in water 15.6 micrograms/liter) was measured. When the fish were preexposed to KME-Sa + CP, the acute tolerance of this mixture in roach increased by 30-39%, but the response was abolished in 31 days. Fish growth remained unchanged during the experiment. Measurement of PCP accumulation revealed no difference in the absorption rate, but under steady-state conditions the degree of bioconcentration was 16% lower (P less than 0.02) in preexposed roach than in their unexposed controls. This difference was entirely accounted for in the head and visceral parts of the fish. Even when no final changes were noted in tolerance and growth rate of the fish, the authors suggest that the significantly lowered body burden implied acclimatizatory compensation under subchronic exposure of this xenobiotic.

  6. Acclimatization of roach, Rutilus rutilus (L.), to toxic components of kraft pulp mill effluents.

    PubMed

    Oikari, A; Kukkonen, J

    1988-06-01

    Roach (Rutilus rutilus) were exposed, along with their appropriate controls, to a simulated bleached kraft mill effluent (KME-Sa + CP) first for 38 days at a concentration of 0.035 X LC50 and then for 14 days at 0.07 X LC50. During the experiment, their tolerances to KME-Sa + CP were tested five times by measuring the 48-hr LC50 values. In addition, the growth of roach was monitored. At the end of the exposure, accumulation of [14C]pentachlorophenol in various parts of the fish (total PCP in water 15.6 micrograms/liter) was measured. When the fish were preexposed to KME-Sa + CP, the acute tolerance of this mixture in roach increased by 30-39%, but the response was abolished in 31 days. Fish growth remained unchanged during the experiment. Measurement of PCP accumulation revealed no difference in the absorption rate, but under steady-state conditions the degree of bioconcentration was 16% lower (P less than 0.02) in preexposed roach than in their unexposed controls. This difference was entirely accounted for in the head and visceral parts of the fish. Even when no final changes were noted in tolerance and growth rate of the fish, the authors suggest that the significantly lowered body burden implied acclimatizatory compensation under subchronic exposure of this xenobiotic. PMID:3168875

  7. Dietary galactooligosaccharide affects intestinal microbiota, stress resistance, and performance of Caspian roach (Rutilus rutilus) fry.

    PubMed

    Hoseinifar, Seyed Hossein; Khalili, Mohsen; Rostami, Hosseinali Khoshbavar; Esteban, M Ángeles

    2013-11-01

    The aim of this study was to assess the effects of galactooligosaccharide (GOS), on the growth performance, stress resistance and intestinal microbiota of Caspian roach (Rutilus rutilus) fry. Specimens (1.36 ± 0.03 g) were fed either a basal control diet (0% GOS, non-supplemented) or the basal diet supplemented with 1% and 2% of GOS. After 7 weeks of the feeding trials, growth factors (final weight, weight gain, specific growth rate, condition factor and food conversion ratio) as well as body composition, resistance to salinity stress and autochthonous intestinal microbiota were assessed. Results demonstrated that at the end of the trial growth factors (final weight, weight gain, SGR, FCR) were significantly higher in 2% GOS fed fish (P < 0.05). In addition, supplementation of GOS significantly increased both survival rate (P < 0.05), and resistance to a salinity stress challenge of prebiotic fed groups (P < 0.05). However, body composition and the total autochthonous intestinal heterotrophic bacteria counts remained unaffected in different treatments (P > 0.05). Nevertheless, autochthonous lactic acid bacteria levels were significantly elevated in fish fed 2% dietary GOS (P < 0.05). These results confirm that GOS improves growth performance, stress resistance and modulates intestinal microbiota by increasing lactic acid bacteria of Caspian roach fry, a very important fish species in the Caspian Sea. PMID:23973845

  8. The interactions of abiotic and biotic factors influencing perch Perca fluviatilis and roach Rutilus rutilus populations in small acidified boreal lakes.

    PubMed

    Linlřkken, A N; Hesthagen, T

    2011-08-01

    Four small, acidified boreal lakes, all sustaining populations of perch Perca fluviatilis, roach Rutilus rutilus and pike Esox lucius, were studied in four successive years. Three lakes were moderately acidified (mean pH of 5·61-5·83), while the fourth was more acidic (mean pH of 5·16) and had a sparse population of R. rutilus. Perca fluviatilis density was higher in this lake (1004 ha(-1)) than in the other three (355-717 ha(-1)), where R. rutilus dominated in terms of numbers (981-2185 ha(-1)). Large, potentially predatory, P. fluviatilis were most abundant in the lake with clearest water, and these seemed to have a negative effect on P. fluviatilis density. Perca fluviatilis mean mass was negatively correlated with R. rutilus biomass and was highest in the most acidic lake with the sparse R. rutilus and the highest P. fluviatilis density. Perca fluviatilis mass correlated positively with pH in two lakes (with the highest fish biomass), suggesting that low pH affected P. fluviatilis mass negatively. Perca fluviatilis growth correlated positively with summer (July to August) air temperature in the lake with sparse R. rutilus, thus differing from P. fluviatilis and R. rutilus growth in the other three lakes. The mean age of P. fluviatilis was generally lower than that of R. rutilus and was lowest in the two lakes with the highest fish biomass, indicating that adult mortality was affected by density-induced factors. PMID:21781101

  9. The progestin levonorgestrel disrupts gonadotropin expression and sex steroid levels in pubertal roach (Rutilus rutilus).

    PubMed

    Kroupova, H K; Trubiroha, A; Lorenz, C; Contardo-Jara, V; Lutz, I; Grabic, R; Kocour, M; Kloas, W

    2014-09-01

    The aim of the present study was to investigate the effects of the synthetic progestin levonorgestrel (LNG) on the reproductive endocrine system of a teleost fish, the roach (Rutilus rutilus). Pubertal roach were exposed for 28 days in a flow-through system to four concentrations of LNG (3, 31, 312, and 3124 ng/l). Both males and females treated with 3124 ng/l LNG exhibited the upregulated levels of vitellogenin and oestrogen receptor 1 mRNA in the liver. At the same concentration, LNG caused a significant upregulation of the mRNA expression of the gene encoding luteinising hormone ?-subunit (lh?) and the suppression of the mRNA expression of the gene encoding follicle-stimulating hormone ?-subunit (fsh?) in the pituitary of both male and female roach. A lower LNG concentration (312 ng/l) suppressed mRNA expression of fsh? in males only. Females treated with 3124 ng/l LNG exhibited significantly lower plasma 11-ketotestosterone (11-KT) and oestradiol (E2) concentrations, whereas their testosterone (T) level was higher compared with the control. Females exposed to 312 ng/l LNG presented significantly lower plasma E2 concentrations. Males exposed to ?31 ng/l LNG exhibited significantly reduced 11-KT levels. As determined through a histological analysis, the ovaries of females were not affected by LNG exposure, whereas the testes of males exposed to 31 and 312 ng/l LNG exhibited a significantly higher percentage of spermatogonia B compared with the control. The results of the present study demonstrate that LNG disrupts the reproductive system of pubertal roach by affecting the pituitary gonadotropin expression and the sex steroid levels. This disruption was determined to occur in males after exposure to an environmentally relevant concentration (31 ng/l). Moreover, the highest tested concentration of LNG (3124 ng/l) exerted an oestrogenic effect on fish of both sexes. PMID:24893273

  10. Infrasound initiates directional fast-start escape responses in juvenile roach Rutilus rutilus.

    PubMed

    Karlsen, Hans E; Piddington, Robert W; Enger, Per S; Sand, Olav

    2004-11-01

    Acoustic stimuli within the sonic range are effective triggers of C-type escape behaviours in fish. We have previously shown that fish have an acute sensitivity to infrasound also, with acceleration thresholds in the range of 10(-5) m s(-2). In addition, infrasound at high intensities around 10(-2) m s(-2) elicits strong and sustained avoidance responses in several fish species. In the present study, the possible triggering of C-escapes by infrasonic single-cycle vibrations was examined in juvenile roach Rutilus rutilus. The fish were accelerated in a controlled and quantifiable manner using a swing system. The applied stimuli simulated essential components of the accelerations that a small fish would encounter in the hydrodynamic flow field produced by a predatory fish. Typical C- and S-type escape responses were induced by accelerations within the infrasonic range with a threshold of 0.023 m s(-2) for an initial acceleration at 6.7 Hz. Response trajectories were on average in the same direction as the initial acceleration. Unexpectedly, startle behaviours mainly occurred in the trailing half of the test chamber, in which the fish were subjected to linear acceleration in combination with compression, i.e. the expected stimuli produced by an approaching predator. Very few responses were observed in the leading half of the test chamber, where the fish were subjected to acceleration and rarefaction, i.e. the stimuli expected from a suction type of predator. We conclude that particle acceleration is essential for the directionality of the startle response to infrasound, and that the response is triggered by the synergistic effects of acceleration and compression. PMID:15531639

  11. A revision of the Rutilus complex from Mediterranean Europe with description of a new genus, Sarmarutilus, and a new species, Rutilus stoumboudae (Teleostei: Cyprinidae).

    PubMed

    Bianco, Pier Giorgio; Ketmaier, Valerio

    2014-01-01

    By combining morphology, ecology, biology, and biogeography with the available molecular (sequence variation of the entire mitochondrial cytochrome b gene; cyt-b) and karyology data, the taxonomy of several species of the Rutilus complex inhabiting southern Europe is revised. Rutilus stoumboudae, new species, is described from Lake Volvi, Greece. It differs from Rutilus rutilus in possessing more total GR and less branched rays in both dorsal and anal fins and in its placement in the cyt-b based phylogeny of the genus. The resurrected genus Leucos Heckel, 1843 (type species Leucos aula, Bonaparte, 1841), which according to molecular data diverged from Rutilus more than 5 million years ago, during the Messinian salinity crisis, includes five species of small size, without spinous tubercles on scales and head in reproductive males, pharyngeal teeth formula 5-5, and all show a preference for still waters. Leucos aula is the Italian species endemic in the Padany-Venetian district: L. basak is widespread in Croatia, Albania, Montenegro and former Yugoslav Republic of Macedonia (FYROM); L. albus, recently described from Lake Skadar, Montenegro, is also found in rivers Moraca and Zeta (Montenegro). L. albus differs from L. basak, its closest relative, in having more scales on the LL and less anal-fin rays; L. panosi is endemic to the western-Greece district, and L. ylikiensis is endemic to lakes Yliki and Paralimni in eastern Greece (introduced in Lake Volvi). Among the nominal species examined, Rutilus karamani, R. ohridanus, R. prespensis and R. prespensis vukovici are all junior synonyms of Leucos basak. Rutilus vegariticus is definitively regarded as junior synonym for R. rutilus. Sarmarutilus n.gen. is a monotypic genus, with Sarmarutilus rubilio as the type species. According to phylogenetic data, Sarmarutilus rubilio is basal to a cluster of species that includes Leucos basak, L. albus, L. aula, L. panosi and L. ylikiensis. Sarmarutilus possibly evolved in pre-Messinian time, in the Lago Mare, entered the Mediterranean area during the Messinian Lago Mare phase of the Mediterranean Sea and survived only in the Tuscany- Latium district. This genus differs from Leucos in having large pearl organs on the central part of head and body scales in mature males and for the habitat preference, being a riverine-adapted species. It differs from Rutilus in pharyngeal teeth formula (5-5 in Sarmarutilus and 6-5 in Rutilus), size (small in Sarmarutilus and large in Rutilus) and for the preferential habitat (riverine vs. still water). Finally, lectotypes for Leucos basak, Leucos aula, and Sarmarutilus rubilio are designated. PMID:25082046

  12. Identification of Diplostomum spp. in the retina of perch Perca fluviatilis and the lens of roach Rutilus rutilus from the Baltic Sea — an experimental study

    Microsoft Academic Search

    Johan Höglund; Jan Thulin

    1982-01-01

    Metacercariae of the genus Diplostomum dwelling in the retina of perch Perca fluviatilis and the lens of roach Rutilus rutilus were identified on the basis of adults obtained by feeding various piscivorous birds of the families Laridae, Anatidae and\\u000a Phasianidae with metacercariae on an experimental basis. Both morphological studies of the metacercariae and adults obtained\\u000a from the intestine of the

  13. Environmental factors regulate the effects of roach Rutilus rutilus and pike Esox lucius on perch Perca fluviatilis populations in small boreal forest lakes.

    PubMed

    Olin, M; Vinni, M; Lehtonen, H; Rask, M; Ruuhijärvi, J; Saulamo, K; Ala-Opas, P

    2010-04-01

    In this study of 18 small boreal forest lakes, the effects of abiotic and biotic factors (roach Rutilus rutilus and pike Esox lucius) on various population variables of perch Perca fluviatilis were examined. As a single variable, the gillnet catch per unit effort (CPUE) of R. rutilus was negatively related to the mean mass of small (< 200 mm) and the growth rate of young (1-2 years) P. fluviatilis. The mean mass of large (> or = 200 mm) P. fluviatilis was the highest at intermediate CPUE of R. rutilus. Redundancy analysis including environmental factors and P. fluviatilis population variables suggested that 'predation-productivity-humus' gradient affected P. fluviatilis populations by decreasing the CPUE and mean mass of small individuals but increasing these variables of large individuals. The CPUE of R. rutilus and lake area had a negative effect on small and a positive effect on large P. fluviatilis growth rate. In small boreal forest lakes, P. fluviatilis populations are affected by the partially opposite forces of competition by R. rutilus and predation by E. lucius, and the intensity of these interactions is regulated by several environmental factors. PMID:20537014

  14. Metabolomics Reveals Target and Off-Target Toxicities of a Model Organophosphate Pesticide to Roach (Rutilus rutilus): Implications for Biomonitoring

    PubMed Central

    2011-01-01

    The ability of targeted and nontargeted metabolomics to discover chronic ecotoxicological effects is largely unexplored. Fenitrothion, an organophosphate pesticide, is categorized as a “red list” pollutant, being particularly hazardous to aquatic life. It acts primarily as a cholinesterase inhibitor, but evidence suggests it can also act as an androgen receptor antagonist. Whole-organism fenitrothion-induced toxicity is well-established, but information regarding target and off-target molecular toxicities is limited. Here we study the molecular responses of male roach (Rutilus rutilus) exposed to fenitrothion, including environmentally realistic concentrations, for 28 days. Acetylcholine was assessed in brain; steroid metabolism was measured in testes and plasma; and NMR and mass spectrometry-based metabolomics were conducted on testes and liver to discover off-target toxicity. O-demethylation was confirmed as a major route of pesticide degradation. Fenitrothion significantly depleted acetylcholine, confirming its primary mode of action, and 11-ketotestosterone in plasma and cortisone in testes, showing disruption of steroid metabolism. Metabolomics revealed significant perturbations to the hepatic phosphagen system and previously undocumented effects on phenylalanine metabolism in liver and testes. On the basis of several unexpected molecular responses that were opposite to the anticipated acute toxicity, we propose that chronic pesticide exposure induces an adapting phenotype in roach, which may have considerable implications for interpreting molecular biomarker responses in field-sampled fish. PMID:21410251

  15. Differential habitat use and antipredator response of juvenile roach (Rutilus rutilus) to olfactory and visual cues from multiple predators.

    PubMed

    Martin, Charles W; Fodrie, F Joel; Heck, Kenneth L; Mattila, Johanna

    2010-04-01

    The indirect, behavioral effects of predation and predator-predator interactions can significantly alter the trophic ecology of many communities. In numerous instances, the strength of these effects may be determined by the ability of prey to identify predation risk through predator-specific cues and respond accordingly to avoid capture. We exposed juvenile roach (Rutilus rutilus), a common forage fish in many brackish and freshwater environments, to vision and/or olfactory cues from two predators with different hunting methods: northern pike (Esox lucius, an ambush predator) and European perch (Perca fluviatilis, a roving predator). Our results demonstrated that responses of roach to perceived risk (as evidenced by their selection of structured or open-water habitats) were highly dependent on cue type and predator identity. For instance, roach responded to olfactory cues of pike by entering open-water habitat, but entered structured habitat when presented with a vision cue of this predator. Opposite responses were elicited from roach for both olfactory and visual cues of perch. Interestingly, roach defaulted to selection of structured habitat when presented with vision + olfaction cues of either predator. Moreover, when presented individual cues of both predators together, roach responded by choosing open-water habitat. Upon being presented with vision + olfaction cues of both predators, however, roach strongly favored structured habitat. Differences in habitat selection of roach were likely in response to the alternative foraging strategies of the two predators, and suggest that prey species may not always use structured habitats as protection. This appears particularly true when a threat is perceived, but cannot immediately be located. These results provide insight to the complex and variable nature by which prey respond to various cues and predators, and offer a mechanistic guide for how behaviorally mediated and predator-predator interactions act as structuring processes in aquatic systems. PMID:20127367

  16. Impact of a short-term diazinon exposure on the osmoregulation potentiality of Caspian roach (Rutilus rutilus) fingerlings.

    PubMed

    Katuli, Kheyrollah Khosravi; Amiri, Bagher Mojazi; Massarsky, Andrey; Yelghi, Saeed; Ghasemzadeh, Javad

    2014-08-01

    The stocks of Caspian roach (Rutilus rutilus), an economically important species in the Caspian Sea, are depleting. Each year millions of artificially produced fingerlings of this species are restocked in the mouth of rivers of the Southern Caspian Sea (e.g. Qare Soo River), where they are exposed to pesticides originating from regional rice and orchard fields. This early exposure to pesticides could affect the hypo-osmoregulatory ability of juvenile fish. Thus, in this study, Caspian roach fingerlings were exposed to environmentally-relevant concentrations of the organophosphate insecticide diazinon for 96 h in fresh water and then transferred to diazinon-free brackish water (BW) for another 96 h. We report that cortisol and glucose levels were significantly increased in all diazinon treatments at all sampling time points in comparison to the control group. Moreover, the thyroid hormone levels of TSH, T4, and T3 significantly decreased in diazinon-exposed fish even after the transfer to BW. The electrolytes were differentially affected during the exposure to diazinon and after the transfer to BW. The number of chloride cells in the gill tissue was significantly increased during diazinon exposure at the higher concentrations and decreased to control levels after transfer to BW. Finally, gill and kidney tissues showed many histopathological changes in diazinon-exposed fish even after 240 h in BW. These results suggest that the release of Caspian roach fingerlings into the diazinon-contaminated Caspian Sea regions may alter their physiology and jeopardize their survival, which could lead to a failure in rebuilding the Caspian roach stocks in the Caspian Sea. PMID:24630256

  17. The seasonality of reproduction in photoperiod responsive and nonresponsive northern red-backed voles ( Myodes rutilus ) in Alaska

    Microsoft Academic Search

    K. T. Stevenson; I. G. van Tets; L. A. I. Nay

    2009-01-01

    High-latitude arvicoline rodents usually reproduce in warmer months, but winter breeding has been documented in several species, including the northern red-backed vole (Myodes rutilus (Pallas, 1779) Wilson and Reader, 2005; for- merly Clethrionomys rutilus (Pallas, 1779)). We tested whether the reproductive condition of the species is linked to changes in environmental parameters or its body condition, and we tested the

  18. Parasite fauna of bream Abramis brama and roach Rutilus rutilus from a man-made waterway and a freshwater habitat in northern Germany.

    PubMed

    Rückert, Sonja; Klimpel, Sven; Palm, Harry Wilhelm

    2007-03-13

    Fifty specimens each of bream Abramis brama and roach Rutilus rutilus were examined for metazoan parasite fauna and trichodinid ciliates; 25 specimens of each species were collected from the Kiel Canal, a man-made waterway, and a nearby freshwater lake, the Dieksee. This is the first detailed parasitological examination of A. brama and R. rutilus at these locations: 30 parasite species were found, comprising 4 protozoans, 4 myxozoans, 5 digeneans, 3 monogeneans, 2 cestodes, 6 nematodes, 2 acanthocephalans, 3 crustaceans and 1 hirudinean. The crustacean Caligus lacustris occurred in both habitats while 2 other crustacean species, 2 acanthocephalans and 1 hirudinean were recorded exclusively for the lake habitat. Larval as well as adult stages of the different parasite species were found, indicating that both fish species act as intermediate and final hosts in both habitats. The Kiel Canal (total of 17 parasite species) showed a lower parasite species richness for A. brama and R. rutilus (14 and 10 parasite species, respectively) than the lake (25 parasite species). A. brama had a higher parasite richness (22 species) than R. rutilus (16 species) in the lake habitat. Most parasites collected were of freshwater origin. Consequently, the observed infection pattern of both fish species in the waterway is mainly influenced by the limited salinity tolerance of freshwater parasites, which are negatively affected even by a salinity of 2.3 to 4.5. In the central Kiel Canal, neither fish species was infected with marine parasites of low host specifity. These parasites are either limited by the low salinity at this sampling site (<4.5 to 6.0) or they cannot enter the canal due to the environmental conditions prevailing in this artificial brackish water habitat. Thus, the canal may comprise a natural barrier preventing the distribution of North Sea parasites into the Baltic Sea. However, the brackish water Baltic Sea nematodes Paracuaria adunca and Cosmocephalus obvelatus were found in R. rutilus from the canal, demonstrating the ability of some parasite species to invade and extend their range of distribution through this man-made shipping route from the Baltic to the North Sea. PMID:17465307

  19. Fingerling production and stock enhancement of Mahisefid ( Rutilus frisii kutum ) lessons for others in the south of Caspian Sea

    Microsoft Academic Search

    H. A. Abdolhay; S. K. Daud; S. Rezvani Ghilkolahi; M. Pourkazemi; S. S. Siraj; M. K. Abdul Satar

    2011-01-01

    Rutilus frisii kutum (Kamensky 1901) is one of the economically important fishes that migrate for spawning to rivers in the Caspian Sea. However,\\u000a the fish populations have slowly decreased in recent years. The declining of these resources has resulted from some activities\\u000a by the Iranian Fisheries Organization (IFO is responsible for stock enhancement) to catch some broodstocks of Rutilus frisii

  20. Normal axial skeleton structure in common roach Rutilus rutilus (Actinopterygii: Cyprinidae) and malformations due to radiation contamination in the area of the Mayak (Chelyabinsk Province, Russia) nuclear plant.

    PubMed

    Bogutskaya, N G; Zuykov, M A; Naseka, A M; Anderson, E B

    2011-10-01

    This study was designed to describe normal axial skeletal structure in common roach Rutilus rutilus from putative unaffected environmental conditions, and the occurrence of skeletal malformations in the fish from an area under radiation contamination. Specimens were collected from water bodies of the Techa Cascade Reservoirs located near the Mayak atomic industry plant in the River Ob' drainage, Chelyabinsk Province, Russia. One sample was collected from Lake Irtyash, a reservoir of drinkable water, supplying the town of Ozersk, and the other one from a technical reservoir which is a storage of liquid radioactive waste from Mayak and characterized by high radioactive contamination (mostly (90)Sr and (137)Cs). A comparison was made with historical material collected from the River Ob' before the middle of the 20th century, i.e. before the environment became affected by radioactive contamination. A high number of abnormalities of the axial skeleton were detected in both Mayak samples, in 94 and 97% of examined specimens, in contrast to about 20% in the historical specimens. The abnormalities were in both the unpaired fins and the vertebral column, including the caudal complex and included supernumerary elements, fusions, deformities and displacement of the elements. Most axial skeleton abnormalities, however, were minor, such as splitting, shortening or deformation of spines. Severe defects, such as extensive scolioses, lordoses and kyphoses, were not found. The causes of the abnormalities were not identified in this study, but the high incidence of malformations may be attributed to genetically determined imbalance during development. The almost equal distribution of abnormalities among the fish from non-contaminated and radioactive contaminated reservoirs may be explained by either recent gene flow within the population of R. rutilus in the River Techa system or the effect of unknown unfavourable environmental factors such as chemical pollution. PMID:21967586

  1. Histopathological effects of atrazine on gills of Caspian kutum Rutilus frisii kutum fingerlings.

    PubMed

    Khoshnood, Zahra; Jamili, Shahla; Khodabandeh, Saber

    2015-04-01

    The use of chemical pesticides has increased environmental pollution and affects fishes as non-target organisms. To investigate the toxic effects of the widely used herbicide atrazine on Caspian kutum Rutilus frisii kutum fingerlings, fish were exposed to a sublethal concentration of half LC50 for 96 h. The main alterations visible in the gill tissue were detachment of the epithelium of the lamellae, necrosis, lamellar fusion, hyperplasia, club shaped lamellae, collapse of the lamellae, shrinkage and curling of the lamellae, and ultrastructural alterations such as necrosis of the apical microridges of the pavement cells. Results also showed that the gill ionocytes were fewer in number and larger in size in the atrazine-exposed fish. Atrazine appears to be highly toxic to Caspian kutum fingerlings even at a sublethal concentration (12.47 mg l-1) and acute exposure. This toxicity could affect gill respiration and ion regulation function of fingerlings by damaging tissue, pavement cells, and ionocytes. PMID:25850400

  2. Genotypic and phenotypic evaluation of Rutilus spp. from Skadar, Ohrid and Prespa Lakes supports revision of endemic as well as taxonomic status of several taxa.

    PubMed

    Miloševi?, D; Winkler, K A; Mari?, D; Weiss, S

    2011-11-01

    One mtDNA gene (cytochrome b), one nuclear DNA fragment, five microsatellites and a suite of morphological characters were evaluated in samples of Rutilus spp. from Skadar, Ohrid and Prespa Lakes. Both genetic and phenotypic data supported two sympatric taxa in Lake Skadar, whereby Prespa and Ohrid Lakes revealed only a single taxon each. One of the taxa from Lake Skadar was similar to samples from Lake Prespa, whereas the second taxon was the most divergent in the data set. The estimated time to the most recent common ancestor of these two sympatric taxa in Lake Skadar was between 125 000 and 500 000 years. The data did not support existing taxonomic schemes for Rutilus in these lakes. This study poses the following working hypothesis: (1) Rutilus prespensis lives both in Lake Prespa and Lake Skadar and therefore is not endemic to Lake Prespa, (2) Rutilus ohridanus lives in Lake Ohrid only and therefore could be considered an endemic if its species status is retained and (3) a third recently described taxon (Rutilus albus) sympatric to R. prespensis lives in Lake Skadar. PMID:22026595

  3. Experimental susceptibility of Caspian white fish, Rutilus frisii kutum to Spring viraemia of carp virus.

    PubMed

    Zamani, H; Ghasemi, M; Hosseini, S M; Haghighi Karsidani, S

    2014-01-01

    Caspian white fish (Rutilus frisii kutum) is a fish of the family Cyprinidae, which is commercially harvested from the Caspian Sea. Experimental infection with Spring viraemia of carp virus (SVCV) was conducted in order to examine susceptibility of caspian White Fish and clinical impacts of infection. Fingerling fish were injected intra-peritoneally or waterborne-exposed with SVCV and were monitored daily for 7 weeks. Dead fish and those survived at the end of experimental period were collected for virus isolation and reverse transcriptase polymerase chain reaction analysis. Epithelioma papulosum cyprini cell line was used to re-isolate the virus and indirect fluorescent antibody test was conducted to identify the isolated virus. Infection trials showed that SVCV was highly pathogenic for the Caspian White Fish with mortality rate ranging from 75 to 85 %, depending on the viral challenge model. SVCV genome was detected from dead and apparently healthy fish tissues of both virus exposure models, which showed Caspian White Fish not only can be regarded as a susceptible host, but also serve as a vector of the virus. PMID:24426310

  4. Caspian White Fish (Rutilus frisii kutum) as a host for Spring Viraemia of Carp Virus.

    PubMed

    Ghasemi, M; Zamani, H; Hosseini, S M; Haghighi Karsidani, S; Bergmann, S M

    2014-06-01

    Rutilus frisii kutum is a fish of the Cyprinidae Family which is native in Caspian Sea and commercially cultured in Iran. This study was conducted to investigate susceptibility of Caspian White Fish to Spring Viraemia of Carp Virus (SVCV) infection and to evaluate influence of different challenge routes on virulence of the virus. Fingerlings were infected by immersion, intra-peritoneal (i.p.) injection, cohabitation and orally. Dead and surviving fish were collected for histological examination as well as for virus re-isolation by cell culture, Reverse Transcriptase Polymerization Chain Reaction (RT-PCR) and Indirect Fluorescent Antibody Test (IFAT) analysis. The results indicated that immersion was the best infectious route of transmission with the highest mortality, whereas oral transmission showed the lowest mortality. The virus was also re-isolated from dead fish and identified by IFAT. In addition, histopathological changes including branchial, hepatic and splenic necrosis as well as glomerulonephritis and necrosis in kidney were observed in diseased fish tissues but not in the survivors. RT-PCR on samples obtained from surviving fish tissues detected viral genome in the fish surviving from immersion, i.p. injection and cohabitation challenges but not in the fish infected orally. In conclusion, Caspian White Fish are susceptible to infection by SVCV and virulence of the virus could be influenced by route of transmission. In addition, SVCV could persist in surviving fish, which may serve as reservoirs of the virus, transmitting infection to healthy fish population. PMID:24685241

  5. Taste preferences and taste thresholds to classical taste substances in the carnivorous fish, kutum Rutilus frisii kutum (Teleostei: Cyprinidae).

    PubMed

    Goli, Sheyda; Jafari, Valiollah; Ghorbani, Rassol; Kasumyan, Alexander

    2015-03-01

    The objective of this study was to compare the taste preferences in the closely related sympatric fish species with different feeding patterns. For this purpose, palatability for four classical taste substances was evaluated for carnivorous kutum Rutilus frisii kutum and the results were compared with the taste preferences of the omnivorous roach Rutilus rutilus which had been studied earlier. In addition, the threshold concentration and the dose-response relationship of the most palatable tastants were evaluated and the ability of kutum to differentiate food with tastants in different concentrations was estimated. It was found that citric acid significantly increases the agar gel pellet consumption within the range of concentrations from 0.01M to 0.52M; the pellets with a concentration of 0.026M were the most palatable. The pellet consumption is significantly different if the concentration of citric acid in the pellets differs more than two times. The absolute threshold concentration is 0.01M, or 2.74?g of citric acid per pellet. Sucrose and NaCl have deterrent taste at the highest concentrations tested (0.29 and 1.73M, respectively). Both substances are palatable at 10 times lower concentrations and become indifferent after further gradual decrease in their concentration. CaCl2 decreases the pellets consumption at 0.9M but is an indifferent tastant at lower concentrations (0.45, 0.09 and 0.045M). The number of rejections and repeated grasps of a food pellet is fewness and is not related to the pellet's palatability, while the retention time of pellet in the oral cavity positively and highly correlates with the pellet's palatability. Kutum have opposite taste preferences for most substances tested in comparison with the roach. It indicates that the taste preferences mediated by the oral taste receptors are different in closely related sympatric fish displayed diet divergences. PMID:25497081

  6. Effect of copper sulfate on the survival and growth performance of Caspian Sea kutum, Rutilus frisii kutum.

    PubMed

    Gharedaashi, Esmail; Nekoubin, Hamed; Imanpoor, Mohammad Reza; Taghizadeh, Vahid

    2013-01-01

    The aim of present study was to determine the LC50/96 h value of copper sulfate and determine the growth performance of Caspian Sea kutum) Rutilus frisii kutum (fingerlings during 60-days sub-lethal copper (Cu). After acclimation period to two weeks, for determine the LC50/96 h value, total of 27 aquarium with a capacity of 60 L each stocked with 10 fishes an aquarium. Tunney four aquarium and 8 concentrations of (Cu) composed the 24 treatments while 3 other aquaria were used as control. For each treatment, three replications were conducted. And experiment to determine the growth performance fish were transferred into fiberglass aquaria of 200 L water capacity for growth trials. The treated fish were kept in the aquarium containing sub-lethal concentrations of Cu (0.11 and 0.23 mg L(-1)) and affected to grow for 60 days, while control fish were placed in metal free water. The results indicated that median lethal concentrations (LC50) of copper to Caspian Sea kutum for 96 h exposure was 2.310 ppm. The chronic sub-lethal water-borne Cu exposure to the fish exerted that fish had significantly decreased final body weight in comparison to control group. The copper sulfate also had significant negative effects on specific growth rate (SGR) and feed conversion efficiency (FCE) in comparison to those fed the control group. The feed conversion ratio (FCR) and condition factor (CF) were significantly increased in comparison with the control group (P?Rutilus frisii kutum). PMID:24133647

  7. [Density-dependent regulation in populations of red-backed voles (Myodes rutilus) in optimal and suboptimal habitats of south-west Siberia].

    PubMed

    Novikov, E A; Panov, V V; Moshkin, M P

    2012-01-01

    In a population of red-backed voles (Myodes rutilus) that live in optimal habitats (mountain taiga of North-Eastern Altai) in the years of peak density we have observed total suppression of sexual maturation of young animals which is known to be the main mechanism of density regulation. Increase of voles' local density is accompanied by the increase of glucocorticoids in blood of mature and immature individuals of both sexes that argues for the important role of hypothalamic-pituitary-adrenal axis in density dependent regulation. Another population of red-backed voles from south-west Siberia that live in suboptimal habitats (Novosibirsk city vicinity), had significantly lower density. Here, the dynamics of demographic traits and endocrine status of the individuals did not correlate with interannual fluctuations of abundance and density. Even though, the possibility that in suboptimal conditions local density occasionally reaches the values sufficient for the induction of self-regulation cannot be excluded. PMID:22567967

  8. Production of fertile unreduced sperm by hybrid males of the Rutilus alburnoides complex (Teleostei, cyprinidae). An alternative route to genome tetraploidization in unisexuals.

    PubMed Central

    Alves, M J; Coelho, M M; Próspero, M I; Collares-Pereira, M J

    1999-01-01

    The hybrid minnow Rutilus alburnoides comprises diploid and polyploid females and males. Previous studies revealed that diploid and triploid females exhibit altered oogenesis that does not involve random segregation and recombination of the genomes of the two ancestors, constituting unisexual lineages. In the present study, we investigated the reproductive mode of hybrid males from the Tejo basin, using experimental crosses and flow cytometric analysis of blood and sperm. The results suggest that diploid hybrids produced fertile unreduced sperm, transmitting their hybrid genome intact to offspring. Triploid hybrids also produced unreduced sperm, but it was not possible to obtain data concerning their fertility. Finally, tetraploid hybrids produced fertile diploid sperm, which exhibited Mendelian segregation. Tetraploid R. alburnoides may reestablish biparental reproduction, as individuals of both sexes with the appropriate constitution for normal meiosis (two haploid genomes from each parental species) are likely to occur in natural populations. Tetraploids probably have arisen from syngamy of diploid eggs and diploid sperm produced by diploid hybrid males. Diploid hybrid males may therefore play a significant role in the dynamics of the complex, starting the evolutionary process that may ultimately lead to a new sexually reproducing species. PMID:9872966

  9. Effect of a Probiotic Containing Bacillus licheniformis and Bacillus subtilis and Ferroin Solution on Growth Performance, Body Composition and Haematological Parameters in Kutum (Rutilus frisii kutum) Fry.

    PubMed

    Azarin, Hajar; Aramli, Mohammad Sadegh; Imanpour, Mohammad Reza; Rajabpour, Mina

    2015-03-01

    This study aimed to assess the efficacy of BioPlus 2B, a probiotic containing Bacillus licheniformis and B. subtilis and Ferroin solution on growth performance, body composition and haematological parameters in kutum, Rutilus frisii kutum, fry. The fish were fed dry pellets containing various ratios of probiotics and Ferroin for 60 days after absorption of the yolk sac. At the end of the trial, growth indices (final weight, weight gain, specific growth rate, daily growth rate, food conversion ratio and condition factor), body composition (crude protein, crude lipid, ash and moisture) and haematological parameters [haematocrit (Hct), haemoglobin (Hb), red blood cells (RBC), white blood cells (WBC), neutrophils (NEUTR), lymphocytes (LYM), mean cell volume (MCV), mean cell haemoglobin (MCH) and mean cell haemoglobin concentration (MCHC)] were assessed. Regarding body composition, total protein levels were higher, and ash, moisture and lipid levels were lower in fish receiving the probiotic and Ferroin treatments compared with the control group (P < 0.05). Fish receiving diets supplemented with probiotics and Ferroin solution showed significantly better growth than those fed the basal diet (control). RBC, Hct, Hb, MCV, MCH and LYM were all highest in fish fed probiotic (1.6 × 10(9) CFU/g dry pellet) + Ferroin solution (7 mg/kg dry pellet) + dry pellets. These results indicate that the combination of probiotic and Ferroin solution represents an effective dietary supplement for improving carcass quality, growth performance and haematological parameters in kutum fry. PMID:25431124

  10. An energy budget for an omnivorous cyprinid: Rutilus rutilus (L.)

    Microsoft Academic Search

    R. Hofer; G. Krewedl; F. Koch

    1985-01-01

    Two to three year old roach (9–15 g body weight) were fed ad libitum with grass or with meal worms. After three weeks, both groups of fish showed a positive energy budget. However, with a grass diet, production was low (only 7% of that of meal worm feeding fish) with an increased of lipids, whereas the protein content of the

  11. Dead and alive parasites: sexual ornaments signal resistance in the male fish, Rutilus rutilus

    Microsoft Academic Search

    Jouni Taskinen; Raine Kortet

    2002-01-01

    The Hamilton and Zuk hypothesis proposed that male sexual ornaments could signal resistance against local co-evolving parasites. We examined the ornamentation - the breeding tubercles - of roach from five populations in relation to (a) parasite load (intensity\\/prevalence; five species), (b) host resistance (proportion of dead parasites; two species), (c) immune function (spleen size) and (d) somatic condition. The gill

  12. Food of roach ( Rutilus rutilus ) and ide ( Leusiscus idus ): significance of diet shift for interspecific competition in omnivorous fishes

    Microsoft Academic Search

    Ĺge Brabrand

    1985-01-01

    Feeding relationships between roach and ide from two sites in a mesotrophic lake SE Norway are presented and discussed. When animal food supply was scarce, both fish species increased their consumption of macrophytes; roach sevenfold, and ide threefold. Along a typical littoral vegetation gradient, ide fed among helophytes, while roach fed in the zone outside. This different habitat selection was

  13. The predictability of helminth community structure in space: a comparison of fish populations from adjacent lakes

    E-print Network

    Poulin, Robert

    species, perch Perca fluviatilis and roach Rutilus rutilus, collected in different seasons from four; Interspecific associations; Nestedness; Perca fluviatilis; Predictability; Rutilus rutilus 1. Introduction

  14. A meta-analysis of latitudinal variations in life-history traits of roach, Rutilus rutilus, over its geographical range: linear or non-linear relationships?

    Microsoft Academic Search

    Jyrki Lappalainen; Ali Serhan Tarkan; Chris Harrod

    2008-01-01

    Summary 1. We collated information from the literature on life history traits of the roach (a generalist freshwater fish), and analysed variation in absolute fecundity, von Bertalanffy parameters, and reproductive lifespan in relation to latitude, using both linear and non-linear regression models. We hypothesized that because most life history traits are dependent on growth rate, and growth rate is non-linearly

  15. Biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) studied in pike ( Esox lucius), perch ( Perca fluviatilis) and roach ( Rutilus rutilus) from the Baltic Sea

    Microsoft Academic Search

    Sven Burreau; Yngve Zebühr; Dag Broman; Rasha Ishaq

    2004-01-01

    Pike, perch and roach from rural waters of the Baltic Sea were investigated for possible biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). For this we used data on ?15N, weight and sex of the fish. We were able to separate body size effects from trophic position effects on biomagnification. Both these parameters lead to biomagnification of PCBs

  16. Biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) studied in pike (Esox lucius), perch (Perca fluviatilis) and roach (Rutilus rutilus) from the Baltic Sea.

    PubMed

    Burreau, Sven; Zebühr, Yngve; Broman, Dag; Ishaq, Rasha

    2004-05-01

    Pike, perch and roach from rural waters of the Baltic Sea were investigated for possible biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). For this we used data on delta15N, weight and sex of the fish. We were able to separate body size effects from trophic position effects on biomagnification. Both these parameters lead to biomagnification of PCBs and PBDEs. All investigated PCBs (tri- to deca-CBs) biomagnify and the biomagnification potential is positively correlated with hydrophobicity up to log Kow 8.18. Tri- to hepta-BDEs also biomagnify but showed a maximum biomagnification for the penta-BDEs (log Kow 6.46-6.97). The biomagnification of hexa- to hepta-PBDEs was negatively correlated with degree of bromination, likely due to large molecular size or high molecular weight (644-959 Da). Octa-, nona- and deca-BDEs did not biomagnify but were found in two (octa-BDE) and three (nona- and deca-BDEs) of the species, respectively. Increased size of pike is correlated with increased lipid weight based PCB and PBDE concentrations in males but not in females and mean PCB and PBDE concentrations in males are generally higher than in females. For the least hydrophobic PCBs, no sex difference is observed, probably as a consequence of faster clearance of these substances over the gills, making the spawning clearance of PCBs and PBDEs of lesser relative importance. PMID:15051373

  17. Evidence for Endocrine Disruption in Perch ( Perca fluviatilis) and Roach ( Rutilus rutilus) in a Remote Swedish Lake in the Vicinity of a Public Refuse Dump

    Microsoft Academic Search

    Erik Noaksson; Ulla Tjärnlund; Albertus T. C. Bosveld; Lennart Balk

    2001-01-01

    A two-year study on perch (Perca fluviatilis) in Lake Molnbyggen, Sweden, located in a pristine area but with a public refuse dump in the vicinity, has been conducted. The mechanistic approach through a set of biomarkers during the first year included age, condition, somatic growth, liver, gonad, and spleen weights, and a number of other physiological variables, in addition to

  18. A survey of the spawning of perch (Perca fluviatilis), pike (Esox lucius), and roach (Rutilus rutilus), using artificial spawning substrates in lakes

    Microsoft Academic Search

    C. Gillet; J. P. Dubois

    1995-01-01

    The development of spawning in perch, pike and roach in Lake Geneva has been studied by means of artificial spawning substrates, laid at different depths, from 1984 to 1993. In Lake Geneva, perch spawned in May. A rise of surface water temperature up to 14 °C stimulated spawning activity while bad weather (surface temperature at 10 °C) induced a spread

  19. This is an author-deposited version published in: http://oatao.univ-toulouse.fr/ Eprints ID: 6158

    E-print Network

    Paris-Sud XI, Université de

    roach (Rutilus rutilus L.), perch (Perca fluviatilis L.), and pike (Esox lucius L.). The two methods vegetation. It is likely microhabitat; scuba diving; lake; Rutilus rutilus; Perca fluviatilis; Esox

  20. Roles of spatial partitioning, competition, and predation in the North American invasion of an exotic mosquito.

    PubMed

    Freed, T Z; Leisnham, P T

    2014-06-01

    Invasion success and species coexistence are often mediated by species interactions across patchily distributed habitats and resources. The invasive mosquito Aedes japonicus japonicus has established in the North American range of the competitively superior resident congener, Aedes albopictus, and the predatory native mosquito Toxorhynchites rutilus. We tested predictions for two hypotheses of invasion success and species coexistence: keystone predation and spatial partitioning. We tested competition between A. japonicus japonicus and A. albopictus with or without T. rutilus in laboratory microcosms, and measured abundances of A. japonicus japonicus, A. albopictus, other resident competing mosquito species, and the presence of T. rutilus among tree holes and tires in metropolitan Washington, DC. In laboratory microcosms, A. albopictus was competitively dominant over A. japonicus japonicus, which is consistent with the few prior studies of competition between these two Aedes species. T. rutilus predation severely lowered performances of both Aedes species but more severely lowered A. japonicus japonicus performance than A. albopictus performance when all three species co-occurred, thus yielding no evidence for keystone predation. Consistent with the spatial partitioning hypothesis, A. japonicus japonicus was negatively correlated and independently aggregated with A. albopictus and all combined resident mosquito competitors and was not associated with T. rutilus among field containers. These results suggest that predation from T. rutilus and competition from A. albopictus are barriers to the spread of A. japonicus japonicus, but that A. japonicus japonicus may escape these interspecific effects by utilizing spatially partitioned container habitats. PMID:24569942

  1. Effect of different cooking methods on minerals, vitamins and nutritional quality indices of kutum roach (Rutilus frisii kutum).

    PubMed

    Hosseini, Hedayat; Mahmoudzadeh, Maryam; Rezaei, Masoud; Mahmoudzadeh, Leila; Khaksar, Ramin; Khosroshahi, Nader Karimian; Babakhani, Aria

    2014-04-01

    In this study, the influence of four cooking methods (baking, boiling, microwaving and frying) was evaluated on the nutritional value of kutum roach. Proximate, fatty acid composition, vitamin and mineral contents and also nutritional quality indices (NQI) of kutum roach were investigated before and after cooking treatment. All treated samples showed increase in protein, ash and lipid contents and decrease in the content of total omega-3 fatty acids (n-3) in comparison to raw fish fillets (control group). Cooking methods had no significant effect on omega-6 fatty acids (n-6) except for frying that increased it. Nonetheless, all of the cooking methods reduced vitamin B1, A and D contents. Boiling significantly decreased mineral contents including Na, K, P and Zn. Considering the overall nutritional quality indices, vitamin and mineral contents, baking is the best cooking method among other applied methods. PMID:24262530

  2. Predation resistance does not trade off with competitive ability in early-colonizing mosquitoes

    PubMed Central

    Murrell, Ebony G.; Juliano, Steven A.

    2013-01-01

    The tradeoff between colonization and competitive ability has been proposed as a mechanism for ecological succession, and this tradeoff has been demonstrated in multiple successional communities. The tradeoff between competitive ability and predation resistance is also a widely-described phenomenon; however, this tradeoff is not usually postulated as a cause of ecological succession. Early successional species that arrive before predator colonization could be either (1) Less vulnerable to predation than their successors, by virtue of being poor competitors (direct competition-predation tradeoff); (2) Equally or more vulnerable to predation, because they normally colonize ahead of predators in succession and therefore are not evolutionarily adapted to avoid predators that they rarely encounter (no competition-predation tradeoff). To test these alternative hypotheses, we established water-filled containers in an oak-hickory forest. We allowed half of the containers to be naturally colonized by early-successional Culex mosquitoes, mid-successional Aedes mosquitoes, and the mosquito predator Toxorhynchites rutilus. In the other half of the containers we prevented Aedes colonization via systematic removal of Aedes eggs, but allowed Culex and T. rutilus to colonize. The numbers of mature Culex larvae and pupae, and later the total number of Culex, were significantly greater in containers where Aedes had been removed, which suggests that Culex are competitively suppressed by Aedes. Toxorhynchites rutilus abundance and colonization rate were unaffected by the removal of Aedes, and densities of both Culex and Aedes decreased significantly with T. rutilus abundance in both treatments. In-lab bioassays showed that Culex were significantly more vulnerable to predation by T. rutilus than were Aedes. These data are consistent with the hypothesis that Culex and Aedes demonstrate a direct colonization/competition tradeoff, and are inconsistent with the hypothesis of a direct competition/predation tradeoff. PMID:23649756

  3. Predation resistance does not trade off with competitive ability in early-colonizing mosquitoes.

    PubMed

    Murrell, Ebony G; Juliano, Steven A

    2013-11-01

    The tradeoff between colonization and competitive ability has been proposed as a mechanism for ecological succession, and this tradeoff has been demonstrated in multiple successional communities. The tradeoff between competitive ability and predation resistance is also a widely-described phenomenon; however, this tradeoff is not usually postulated as a cause of ecological succession. Early successional species that arrive before predator colonization could be either (1) less vulnerable to predation than their successors, by virtue of being poor competitors (direct competition-predation tradeoff); or (2) equally or more vulnerable to predation, because they normally colonize ahead of predators in succession and therefore are not evolutionarily adapted to avoid predators that they rarely encounter (no competition-predation tradeoff). To test these alternative hypotheses, we established water-filled containers in an oak-hickory forest. We allowed half of the containers to be naturally colonized by early-successional Culex mosquitoes, mid-successional Aedes mosquitoes, and the mosquito predator Toxorhynchites rutilus. In the other half of the containers, we prevented Aedes colonization via systematic removal of Aedes eggs, but allowed Culex and T. rutilus to colonize. The numbers of mature Culex larvae and pupae, and later the total number of Culex, were significantly greater in containers where Aedes had been removed, which suggests that Culex are competitively suppressed by Aedes. Toxorhynchites rutilus abundance and colonization rate were unaffected by the removal of Aedes, and densities of both Culex and Aedes decreased significantly with T. rutilus abundance in both treatments. In-laboratory bioassays showed that Culex were significantly more vulnerable to predation by T. rutilus than were Aedes. These data are consistent with the hypothesis that Culex and Aedes demonstrate a direct colonization-competition tradeoff, and are inconsistent with the hypothesis of a direct competition-predation tradeoff. PMID:23649756

  4. Divergent and Conserved Elements Comprise the Chemoreceptive Repertoire of the Nonblood-Feeding Mosquito Toxorhynchites amboinensis

    PubMed Central

    Zhou, Xiaofan; Rinker, David C.; Pitts, Ronald Jason; Rokas, Antonis; Zwiebel, Laurence J.

    2014-01-01

    Many mosquito species serve as vectors of diseases such as malaria and yellow fever, wherein pathogen transmission is tightly associated with the reproductive requirement of taking vertebrate blood meals. Toxorhynchites is one of only three known mosquito genera that does not host-seek and initiates egg development in the absence of a blood-derived protein bolus. These remarkable differences make Toxorhynchites an attractive comparative reference for understanding mosquito chemosensation as it pertains to host-seeking. We performed deep transcriptome profiling of adult female Toxorhynchites amboinensis bodies, antennae and maxillary palps, and identified 25,084 protein-coding “genes” in the de novo assembly. Phylogenomic analysis of 4,266 single-copy “genes” from T. amboinensis, Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus robustly supported Ae. aegypti as the closest relative of T. amboinensis, with the two species diverged approximately 40 Ma. We identified a large number of T. amboinensis chemosensory “genes,” the majority of which have orthologs in other mosquitoes. Finally, cross-species expression analyses indicated that patterns of chemoreceptor transcript abundance were very similar for chemoreceptors that are conserved between T. amboinensis and Ae. aegypti, whereas T. amboinensis appeared deficient in the variety of expressed, lineage-specific chemoreceptors. Our transcriptome assembly of T. amboinensis represents the first comprehensive genomic resource for a nonblood-feeding mosquito and establishes a foundation for future comparative studies of blood-feeding and nonblood-feeding mosquitoes. We hypothesize that chemosensory genes that display discrete patterns of evolution and abundance between T. amboinensis and blood-feeding mosquitoes are likely to play critical roles in host-seeking and hence the vectorial capacity. PMID:25326137

  5. Divergent and conserved elements comprise the chemoreceptive repertoire of the nonblood-feeding mosquito Toxorhynchites amboinensis.

    PubMed

    Zhou, Xiaofan; Rinker, David C; Pitts, Ronald Jason; Rokas, Antonis; Zwiebel, Laurence J

    2014-10-01

    Many mosquito species serve as vectors of diseases such as malaria and yellow fever, wherein pathogen transmission is tightly associated with the reproductive requirement of taking vertebrate blood meals. Toxorhynchites is one of only three known mosquito genera that does not host-seek and initiates egg development in the absence of a blood-derived protein bolus. These remarkable differences make Toxorhynchites an attractive comparative reference for understanding mosquito chemosensation as it pertains to host-seeking. We performed deep transcriptome profiling of adult female Toxorhynchites amboinensis bodies, antennae and maxillary palps, and identified 25,084 protein-coding "genes" in the de novo assembly. Phylogenomic analysis of 4,266 single-copy "genes" from T. amboinensis, Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus robustly supported Ae. aegypti as the closest relative of T. amboinensis, with the two species diverged approximately 40 Ma. We identified a large number of T. amboinensis chemosensory "genes," the majority of which have orthologs in other mosquitoes. Finally, cross-species expression analyses indicated that patterns of chemoreceptor transcript abundance were very similar for chemoreceptors that are conserved between T. amboinensis and Ae. aegypti, whereas T. amboinensis appeared deficient in the variety of expressed, lineage-specific chemoreceptors. Our transcriptome assembly of T. amboinensis represents the first comprehensive genomic resource for a nonblood-feeding mosquito and establishes a foundation for future comparative studies of blood-feeding and nonblood-feeding mosquitoes. We hypothesize that chemosensory genes that display discrete patterns of evolution and abundance between T. amboinensis and blood-feeding mosquitoes are likely to play critical roles in host-seeking and hence the vectorial capacity. PMID:25326137

  6. The use of Toxorhynchites splendens for identification and quantitation of serotypes contained in the tetravalent live attenuated dengue vaccine

    Microsoft Academic Search

    Nuananong Jirakanjanakit; Mi Mi Khin; Sutee Yoksan; Natth Bhamarapravati

    1999-01-01

    Assurance of identity and quantity is an indispensable part of quality control in the manufacture of vaccines. Dengue-1 PDK13, dengue-2 PDK53, dengue-3 PGMK30F3 and dengue-4 PDK48 in the live attenuated tetravalent dengue vaccine were assayed by identification and quantitation in a mosquito system (Toxorhynchites splendens). Each serotype of dengue virus was identified by dengue specific monoclonal antibodies in the indirect

  7. [Radiation doses and allozyme variability in the population of the northern red-backed vole (Clethrionomys rutilus) from the east urals radioactive trace zone].

    PubMed

    Modorov, M V

    2014-02-01

    The paper estimates the external (due to radionuclides accumulated in the soil) and internal (due to incorporated radionuclides) exposure of rodents that live in the head of the East Urals Radioactive Trace (EURT). It is shown that in the last decades the dose rates were lower than the values that lead to doubling the number of mutations in the allozyme loci in mammals. The variability ofthe eight allozyme loci in populations of northern red-backed voles from the EURT zone and their neighboring plots, as well as the territories of the Urals and Trans-Urals with background levels of radioactive contamination, are analyzed. No differences in the pattern and frequency of allozymes that would distinguish the EURT samples from a number of other populations of the Urals, were found. In the control sample "Sysert", "unique" for the Ural populations of northern red-backed voles, alleles of the loci Got and Sod were marked, conspecific to a closely related species--the bank vole. This fact can be regarded as evidence of recent cross-species hybridization. PMID:25711026

  8. PREDATOR IDENTITY AND ADDITIVE EFFECTS IN A TREEHOLE COMMUNITY

    PubMed Central

    Griswold, Marcus W.; Lounibos, L. Philip

    2007-01-01

    Multiple predator species can interact as well as strongly affect lower trophic levels, resulting in complex, nonadditive effects on prey populations and community structure. Studies of aquatic systems have shown that interactive effects of predators on prey are not necessarily predictable from the direct effects of each species alone. To test for complex interactions, the individual and combined effects of a top and intermediate predator on larvae of native and invasive mosquito prey were examined in artificial analogues of water-filled treeholes. The combined effects of the two predators were accurately predicted from single predator treatments by a multiplicative risk model, indicating additivity. Overall survivorship of both prey species decreased greatly in the presence of the top predator Toxorhynchites rutilus. By itself, the intermediate predator Corethrella appendiculata increased survivorship of the native prey species Ochlerotatus triseriatus and decreased survivorship of the invasive prey species Aedes albopictus relative to treatments without predators. Intraguild predation did not occur until alternative prey numbers had been reduced by approximately one-half. Owing to changes in size structure accompanying its growth, T. rutilus consumed more prey as time progressed, whereas C. appendiculata consumed less. The intermediate predator, C. appendiculata, changed species composition by preferentially consuming A. albopictus, while the top predator, T. rutilus, reduced prey density, regardless of species. Although species interactions were in most cases predicted from pairwise interactions, risk reduction from predator interference occurred when C. appendiculata densities were increased and when the predators were similarly sized. PMID:16676542

  9. The use of Toxorhynchites splendens for identification and quantitation of serotypes contained in the tetravalent live attenuated dengue vaccine.

    PubMed

    Jirakanjanakit, N; Khin, M M; Yoksan, S; Bhamarapravati, N

    1999-02-12

    Assurance of identity and quantity is an indispensable part of quality control in the manufacture of vaccines. Dengue-1 PDK13, dengue-2 PDK53, dengue-3 PGMK30F3 and dengue-4 PDK48 in the live attenuated tetravalent dengue vaccine were assayed by identification and quantitation in a mosquito system (Toxorhynchites splendens). Each serotype of dengue virus was identified by dengue specific monoclonal antibodies in the indirect fluorescent antibody test. Virus content was estimated by calculating the 50% mosquito infectious dose (MID50). Differences from 0 to +/-0.5 log10 were observed between the original monovalent titer and that from the blend which showed no significant difference at 95% confidence limit (P < 0.05). This result indicates that there is no interference between dengue serotypes in mosquitoes infected by intrathoracic inoculation with the virus mixture. It can be also concluded that this mosquito system can be used as an effective measure for infectivity titration of each component in the tetravalent dengue vaccine. PMID:10075167

  10. Habitat complexity and sex-dependent predation of mosquito larvae in containers

    PubMed Central

    Griswold, Marcus W.; Lounibos, L. Philip

    2012-01-01

    Studies in aquatic systems have shown that habitat complexity may provide refuge or reduce the number of encounters prey have with actively searching predators. For ambush predators, habitat complexity may enhance or have no effect on predation rates because it conceals predators, reduces prey detection by predators, or visually impairs both predators and prey. We investigated the effects of habitat complexity and predation by the ambush predators Toxorhynchites rutilus and Corethrella appendiculata on their mosquito prey Aedes albopictus and Ochlerotatus triseriatus in container analogs of treeholes. As in other ambush predator-prey systems, habitat complexity did not alter the effects of T. rutilus or C. appendiculata whose presence decreased prey survivorship, shortened development time, and increased adult size compared to treatments where predators were absent. Faster growth and larger size were due to predator-mediated release from competition among surviving prey. Male and female prey survivorship were similar in the absence of predators, however when predators were present, survivorship of both prey species was skewed in favor of males. We conclude that habitat complexity is relatively unimportant in shaping predator-prey interactions in this treehole community, where predation risk differs between prey sexes. PMID:16041612

  11. Mass spectrometric profiling of glucosamine, glucosamine polymers and their catecholamine adducts. Model reactions and cuticular hydrolysates of Toxorhynchites amboinensis (Culicidae) pupae.

    PubMed

    Kerwin, J L; Whitney, D L; Sheikh, A

    1999-07-01

    Glucosamine (Gln), glucosamine polymers, and their catecholamine adducts were characterized using positive ion electrospray mass spectrometry (ESMS) and tandem mass spectrometry (ESMS-MS). N-acetyldopamine (NADA), a catecholamine found in many insect cuticles, was oxidized using mushroom tyrosinase, and the resulting quinone derivatives were reacted with Gln, (Gln)3, and polymeric glucosamine (chitosan). Adducts of glucosamine and its trisaccharide with NADA were readily identified as [M + H]+ ions in ESMS spectra, and ESMS-MS of selected ions confirmed the condensation of 1-3 NADA residues with Gln. In addition to Gln modification by the quinone derivatives of NADA, other spectra were consistent with the formation of adducts with N-acetylnoradrenaline and moieties formed by intramolecular cyclization following oxidation. The primary amine of glucosamine was involved in initial adduct formation, but the sites for subsequent additions of oxidized NADA to glucosamine, presumably via hydroxyl groups, could not be identified by ESMS alone. The ESMS spectra of chitosan films infused into the spectrometer following solubilization in acidic methanol/water produced spectra similar to that of (Gln)3 up to m/z 502. Ions of gradually decreasing intensity consistent with (Gln)x, where x = 4-8, were observed. Modification of chitosan films following incubation with NADA plus tyrosinase rendered the films insoluble in dilute acid, simulating the cross-linking process proposed to occur during insect cuticle sclerotization. Acid hydrolysates of the pupal stage of the mosquito Toxorhynchites amboinensis, using only two pupal exuviae for the hydrolyses, were infused into the mass spectrometer without preliminary chromatography. Eight amino acids, glucosamine, N-acetylglucosamine, catecholamines, and a variety of polymers incorporating these compound classes were identified. PMID:10436936

  12. Fish predation and offspring survival in the prosobranch snail Viviparus ater

    Microsoft Academic Search

    G. Keller; G. Ribi

    1993-01-01

    In this study we identified some of the predators of the freshwater snail Viviparus ater and estimated offspring survival to the end of the first summer in a natural population. Newborn V. ater were eaten by the fish Barbus barbus, Rutilus rutilus, Scardinius erythrophtalmus and Tinca tinca. Out of 137 guts of Abramis brama caught in Lake Zürich 1 contained

  13. Periphyton-macroinvertebrate interactions in light and fish manipulated enclosures in a clear and a turbid shallow lake

    Microsoft Academic Search

    Lone Liboriussen; Erik Jeppesen; Mette E. Bramm; Majbritt F. Lassen

    2005-01-01

    In a clear and a turbid freshwater lake the biomasses of phytoplankton, periphytic algae and periphytonassociated macrograzers were followed in enclosures with and without fish (Rutilus rutilus) and four light levels (100%, 55%, 7% and < 1% of incoming light), respectively. Fish and light affected the biomass of primary producers and the benthic grazers in both lakes. The biomass of

  14. Aquat. Living Resour., 1993, 6, 285-289 In situ determination of the target strength of roach

    E-print Network

    Guillard, Jean

    (Rutilus rutilus) in lake Bourget with a single beam sounder Jean Guillard and Daniel Gerdeaux INRA estimates. Fish target strength (TS) is essential to express echo integrator measurements in terms of fish the algorithm of Craig and Forbes (1969) to estimate statistically the echo strength distribution using a single

  15. The inf luence of the invasive black bullhead Ameiurus melas on the predatory efficiency of pike Esox lucius L

    Microsoft Academic Search

    K. KREUTZENBERGER; F. L EPRIEUR; S. BROSSE

    2008-01-01

    The influence of the invasive black bullhead Ameiurus melas on the predatory efficiency of the pike Esox lucius was investigated using an additive experimental design. Pike predatory success on 0ţ years roach Rutilus rutilus was significantly reduced in the presence of black bullhead. Among the different hypotheses that may explain such a pattern, the hypothesis of direct competition between pike

  16. ENDOCRINE (SEXUAL) DISRUPTION IS NOT A PROMINENT FEATURE IN THE PIKE (ESOX LUCIUS), A TOP PREDATOR, LIVING IN ENGLISH WATERS

    Microsoft Academic Search

    Emma Vine; Jan Shears; Ronny van Aerle; Charles R. Tyler; John P. Sumpter

    2005-01-01

    The high incidence of intersex roach ( Rutilus rutilus) in some United Kingdom rivers that has been associated with exposure to sewage treatment works (STWs) effluent led us to hypothesize that top predator fish also may be affected by estrogenic chemicals, because they are likely to bioaccumulate lipophilic compounds through a predator-prey relationship. To investigate this possibility, pike (Esox lucius)

  17. Published: January 5, 2011 r 2011 American Chemical Society 1673 dx.doi.org/10.1021/es103232q |Environ. Sci. Technol. 2011, 45, 16731679

    E-print Network

    Tyler, Charles

    -1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan bS Supporting Information ABSTRACT: Feminized responses (reviewed in ref 3). In the case of feminized wild roach (Rutilus rutilus) collected from UK rivers, they show reduced gamete quality4 with the potential for adverse effects on breeding. Femin- ized phenotypes

  18. SClENTIA gerundensis, 24:59-62 (1999) COMMON ERRORS IN THE AUTHORITY OF SCIENTIFIC

    E-print Network

    GarcĂ­a-Berthou, Emili

    (L.) i Perca fluviatilis L., respectivament. La revisiĂł d'una base de dades bibliogriViques en CD Percafluviatilis (L.) en lugar de 10s correctos Rutilus rutilus (L.) y Perca fluviatilis L., respectivamente. La Giles et al. (1990) quote Perca fluviatilis (L.) instead of Perca fluviatilis L. (note errors

  19. Parasite communities of freshwater fish under flood conditions

    Microsoft Academic Search

    Dušan Kadlec; Andrea Šimková; Ji?í Jarkovský; Milan Gelnar

    2003-01-01

    The parasite communities of the freshwater fish species roach (Rutilus rutilus), bitterling (Rhodeus sericeus amarus) and perch (Perca fluviatilis) were investigated during a major flood. Differences in parasite community structure due to changes in the host environment were expected. We therefore tested for differences in parasite species abundance and diversity as a consequence of the flood. Potential changes in parasite

  20. A multifaceted trophic cascade in a detritus-based system: density-, trait-, or processing-chain-mediated effects?

    PubMed Central

    Albeny-Simőes, Daniel; Murrell, Ebony G.; Vilela, Evaldo F.; Juliano, Steven A.

    2015-01-01

    We investigated three pathways by which predators on an intermediate trophic level may produce a trophic cascade in detritus-based systems. Predators may increase lower trophic levels (bacteria) by reducing density of bacteriovores, by altering behavior of bacteriovores, and by processing living bacteriovores into carcasses, feces, and dissolved nutrients that are substrates for bacteria. We tested these pathways in laboratory experiments with mosquitoes in water-filled containers. Larval Toxorhynchites rutilus prey on larval Aedes triseriatus, which feed on bacteria. Using containers stocked with oak leaf infusion as a bacterial substrate, we compared bacterial productivity at 7 and 14 days for: prey alone; prey with a predator; and prey with predation cues but no predator. Controls contained no larvae, either with predation cues or without cues. Predation cues in the control treatment increased bacterial abundance at 7 days, but this effect waned by 14 days. Aedes triseriatus larvae reduced bacterial abundance significantly at 14 days. Predator cues and real predation both eliminated the negative effect of A. triseriatus on bacterial abundance. Predation cues reduced survivorship of A. triseriatus larvae at 14 days, however this effect was smaller than the effect of real predation. We further tested effects of residues from predation as cues or as detritus in a second experiment in which A. triseriatus were killed at similar rates by: real predators; mechanical damage without the predator and carcasses left as detritus; or mechanical damage and carcasses removed. No prey larvae were killed in controls. Bacterial productivity was greater with real predation than in all other treatments and greater when prey larvae were killed or killed and removed, than in controls. Thus we find evidence that all three pathways contribute to the trophic cascade from T. rutilus to bacteria in tree hole systems.

  1. Local and regional factors influence the structure of treehole metacommunities

    PubMed Central

    Paradise, Christopher J; Blue, Jarrod D; Burkhart, John Q; Goldberg, Justin; Harshaw, Lauren; Hawkins, Katherine D; Kegan, Benjamin; Krentz, Tyler; Smith, Leslie; Villalpando, Shawn

    2008-01-01

    Background Abiotic and biotic factors in a local habitat may strongly impact the community residing within, but spatially structured metacommunities are also influenced by regional factors such as immigration and colonization. We used three years of monthly treehole census data to evaluate the relative influence of local and regional factors on our study system. Results Every species responded to at least one of three local environmental factors measured: water volume, leaf litter mass, and presence of a top predator. Several species were affected by water volume, and a non-exclusive group of species were influenced by leaf litter mass. Relative abundance of Aedes triseriatus was higher in treeholes with higher volumes of water, and relative abundances of three out of six other species were lower in treeholes with higher volumes of water. Leaf litter mass positively affected densities of Aedes triseriatus and relative abundance of several dipteran species. The density of the top predator, Toxorhynchites rutilus, affected the relative abundance of the two most common species, A. triseriatus and Culicoides guttipennis. Treeholes with T. rutilus had an average of two more species than treeholes without T. rutilus. We found little evidence of synchrony between pairs of treeholes, either spatially or temporally. There were high levels of spatial and temporal turnover, and spatial turnover increased with distance between patches. Conclusion The strong effects of water volume, leaf litter mass, and presence of a top predator, along with the high temporal turnover strongly suggest that species presence and density are determined by local factors and changes in those factors over time. Both low water volume and high predator densities can eliminate populations in local patches, and those populations can recolonize patches when rain refills or predators exit treeholes. Population densities of the same species were not matched between pairs of treeholes, suggesting variation in local factors and limited dispersal. Distance effects on spatial turnover also support limitations to dispersal in the metacommunity, and we conclude that the weight of evidence favors a strong influence of local factors relative to regional factors. PMID:19099587

  2. Supplement 17, Part 3, Parasite-Subject Catalogue: Parasites: Trematoda And Cestoda

    E-print Network

    Segal, Dorothy B.; Humphrey, Judith M.; Edwards, Shirley J.; Kirby, Margie D.

    1969-01-01

    ?he, 1909 Felis catus domesticus (tenk? crevo) Apophallus miihlingi (J?ger- Zitnan, R., I966 b, 769 ski?ld, 1899) all from CSSR Rutilus rutilus carpathorossicus Leuciscus cephalus L. idus Scardinius erythrophthalraus Alburnus alburnus Blicca...., 1965 a, 121 all from Belorussia Alaria alata (Goeze, 1782) Krause, 1914 Canis lupus Alaria alata Vulpes vulpes ALaria alata Rana esculenta Soitys, ?., 1964 b, 59-62 Poland Svatos, I., I963 a, 174 Czechoslovakia Vojtkov?, L.; Moravec, F...

  3. Long-term light history modulates the light response kinetics of luminosity (L)-type horizontal cells in the roach retina 1 1 Published on the World Wide Web on 7 November 2000

    Microsoft Academic Search

    A. Jenkins; M. W. Hankins

    2000-01-01

    We have examined the effects of prolonged periods of darkness on the responses of luminosity-type horizontal cells (L-HCs) in the freshwater cyprinid, Rutilus rutilus. Two groups of retinae were compared, those recorded after 10 min dark adaptation (SA) and those recorded after 3 h dark adaptation (LA). The results suggest that long-term light history does not modify the general responsiveness

  4. Effect of dissolved oxygen on stomach evacuation rate of juvenile red drum (Sciaenops ocellatus)

    E-print Network

    Becerra Illingworth, Jorge Alberto

    1998-01-01

    gairdneri). Aquaculture 47, 1-10. Persson, L. (1979). The effects of temperature and different food organisms on the rate of gastric evacuation in perch (Perca fluviatilis). Freshwater Biology 9, 99-104. Persson, L. (1981). The effects of temperature... and meal size on the rate of gastric evacuation rate in perch (Perca fluviatilis) fed on fish larvae. Freshwater Biology 11, 131-138. Persson, L. (1982). Rate of food evacuation in roach (Rutilus rutilus) in relation to temperature, and the application...

  5. Feeding efficiency of planktivores under disturbance, the effect of water colour, predation threat and shoal composition.

    PubMed

    Nurminen, L; Estlander, S; Olin, M; Lehtonen, H

    2014-04-01

    The consumption of phantom midge Chaoborus flavicans larvae by Perca fluviatilis showed clear response to water colour, predation threat and shoal composition with the most significant negative effect for water colour. In the case of Rutilus rutilus, no similar combined response was observed and the total prey consumption was significantly negatively affected by predation threat of Esox lucius. The results suggest that differences in life-history traits may result in disparity in species-specific responses to disturbance. PMID:24689675

  6. Bioaccumulation and differential partitioning of polychlorinated biphenyls in freshwater, planktonic food webs

    Microsoft Academic Search

    Olof Berglund; Per Larsson; Göran Ewald; Lennart Okla

    2000-01-01

    The planktonic food chain phytoplankton - zooplankton - young-of-the-year roach (Rutilus rutilus) was stud- ied in 19 lakes in southern Sweden to investigate the bioaccumulation of polychlorinated biphenyls (PCBs). The SPCB concentrations did not steadily increase with increasing trophic level. The SPCB concentrations in zooplankton (400 ng·g lipid-1) were lower than in both phytoplankton (660 ng·g lipid-1) and fish (890

  7. Successional mosquito dynamics in surrogate treehole and ground-container habitats in the northeastern United States: where does Aedes albopictus fit in?

    PubMed

    Johnson, B J; Sukhdeo, M V K

    2013-06-01

    This study assessed the risk of larval displacement of the eastern treehole mosquito, Aedes triseriatus, and the northern house mosquito, Culex pipiens, by Aedes albopictus, the Asian tiger mosquito, during the establishment and successional stages of novel larval mosquito treehole and ground-container habitats in the state of New Jersey, U.S.A. Culex pipiens and Culex restuans were the first mosquito species to colonize ground-container habitats and were the dominant larval species throughout the study period, whereas Ae. albopictus was late to colonize ground habitats and accounted for less than 15% of weekly larval collections once established. Ae. albopictus had a much stronger community presence within treehole ovitraps; however, Ae. albopictus never reached the average larval densities of the expected primary colonizer, Ae. triseriatus. Throughout the study period, the weekly abundances of Ae. triseriatus and Ae. albopictus were positively correlated and there were no significant differences between the abundances of each species. The larval dominance of Ae. triseriatus appears to be enhanced by the presence of Toxorhynchites rutilus septentrionalis, a large predatory mosquito species. When Tx. rut. septentrionalis was present, mature larvae (3(rd) -4(th) instar) of Ae. albopictus were also present in only 16.7% of collections, whereas mature larvae of Ae. triseriatus were collected concurrently with Tx. rut. septentrionalis in 53.8% of collections. These data suggest that Ae. triseriatus is at a greater risk of displacement by Ae. albopictus than are Cx. pipiens and Cx. restuans. PMID:23701622

  8. Effect of boat noise and angling on lake fish behaviour.

    PubMed

    Jacobsen, L; Baktoft, H; Jepsen, N; Aarestrup, K; Berg, S; Skov, C

    2014-06-01

    The effects of disturbances from recreational activities on the swimming speed and habitat use of roach Rutilus rutilus, perch Perca fluviatilis and pike Esox lucius were explored. Disturbances were applied for 4?h as (1) boating in short intervals with a small outboard internal combustion engine or (2) boating in short intervals combined with angling with artificial lures between engine runs. The response of the fish species was evaluated by high-resolution tracking using an automatic acoustic telemetry system and transmitters with sub-minute burst rates. Rutilus rutilus swimming speed was significantly higher during disturbances [both (1) and (2)] with an immediate reaction shortly after the engine started. Perca fluviatilis displayed increased swimming activity during the first hour of disturbance but not during the following hours. Swimming activity of E. lucius was not significantly different between disturbance periods and the same periods on days without disturbance (control). Rutilus rutilus increased their use of the central part of the lake during disturbances, whereas no habitat change was observed in P. fluviatilis and E. lucius. No difference in fish response was detected between the two types of disturbances (boating with and without angling), indicating that boating was the primary source of disturbance. This study highlights species-specific responses to recreational boating and may have implications for management of human recreational activities in lakes. PMID:24813930

  9. Historic hybridization and persistence of a novel mito-nuclear combination in red-backed voles (genus Myodes)

    PubMed Central

    Runck, Amy M; Matocq, Marjorie D; Cook, Joseph A

    2009-01-01

    Background The role of hybridization in generating diversity in animals is an active area of discovery and debate. We assess hybridization across a contact zone of northern (Myodes rutilus) and southern (M. gapperi) red-backed voles using variation in skeletal features and both mitochondrial and nuclear loci. This transect extends approximately 550 km along the North Pacific Coast of North America and encompasses 26 populations (n = 485). We establish the history, geographic extent and directionality of hybridization, determine whether hybridization is ongoing, and assess the evolutionary stability of novel genomic combinations. Results Identification of M. rutilus and M. gapperi based on the degree of closure of the post-palatal bridge was concordant with the distribution of diagnostic nuclear MYH6 alleles; however, an 80 km zone of introgressed populations was identified. The introgressant form is characterized by having mitochondrial haplotypes closely related to the northern M. rutilus on a nuclear background and morphological characteristics of southern M. gapperi. Conclusion Introgression appears to have been historic as pure populations of M. rutilus are now isolated to the north from introgressants or pure M. gapperi by the LeConte Glacier. As we do not find pure M. rutilus or M. gapperi individuals throughout the distribution of the introgressant form, it appears that the introgressants are a self-sustaining entity not requiring continued hybridization between pure parental forms to generate this novel combination of characters. PMID:19460158

  10. Prevalence and sequence comparison of Phyllodistomum folium from zebra mussel and from freshwater fish in the Ebro River.

    PubMed

    Peribáńez, Miguel A; Ordovás, Laura; Benito, Josep; Benejam, Lluís; Gracia, María J; Rodellar, Clementina

    2011-01-01

    We utilised DNA analysis to detect the presence of the digenean Phyllodistomum folium in three cyprinid species, Scardinius erythrophthalmus, Cyprinus carpio and Rutilus rutilus. DNA sequencing of the region containing the genes ITS1-5.8S-ITS2 revealed 100% sequence identity between DNA from the sporocysts found in zebra mussels and DNA from adults located in the urinary system of 29 cyprinid fish. A second genetically different (variation=1.6%) sequence was observed in two samples from R. rutilus. In our opinion, the existence of a complex of species reported as P. folium is supported by recent genetic studies, including our own results. The overall prevalence of P. folium in mussels from the Ebro River was 4.67% in 2006, although during the summer months the rates frequently exceeded 10%. PMID:20971214

  11. [Gene-geographical variation and genetic differentiation in red-backed voles of the genus Clethrionomys (Rodentia, Cricetidae) in the Okhotskii region].

    PubMed

    Frisman, L V; Kartavtseva, I V; Pavlenko, M V; Kostenko, V A; Suzuki, Hitoshi; Ivasa, Masahiro; Nakata, Keisuke; Cherniavski?, F B

    2002-05-01

    Thirteen enzyme systems and three nonenzyme proteins were electrophoretically analyzed in red-backed voles of the genus Clethrionomys. In total, 25 loci were interpreted. Gene-geographic variation was studied and indices of genetic variability and differentiation were determined. By the distribution of electrophoretic variants of hemoglobin, C. rutilus was shown to be divided into two geographical groups (northern and southern). A low level of genetic differentiation was revealed in the island isolates of C. rutilus and C. rufocanus. Separation of C. rufocanus, C. rex, and C. sicotanensis into a superspecies complex was confirmed. A study of differential G- and C-banding on C. rutilus and C. rufocanus chromosomes did not reveal intraspecific variation of autosomes. In these species, karyotypes of voles from Kamchatka Peninsula were studied for the first time. They appeared to be morphologically similar to the karyotypes continental voles by both autosomes and sex chromosomes. PMID:12068550

  12. Urban Mosquito Fauna in Mérida City, México: Immatures Collected from Containers and Storm-water Drains/Catch Basins

    PubMed Central

    Baak-Baak, Carlos M.; Arana-Guardia, Roger; Cigarroa-Toledo, Nohemi; Puc-Tinal, María; Coba-Tún, Carlos; Rivero-Osorno, Víctor; Lavalle-Kantun, Damián; Lorońo-Pino, María Alba; Machain-Williams, Carlos; Reyes-Solis, Guadalupe C.; Beaty, Barry J.; Eisen, Lars; García-Rejón, Julián E.

    2014-01-01

    We examined the species composition and temporal occurrence of immature mosquitoes in containers and storm-water drains/catch basins from November 2011 to June 2013 in Mérida City, México. A wide range of urban settings were examined, including residential premises, vacant lots, parking lots, and streets or sidewalks with storm-water drains/catch basins. In total, 111,776 specimens of 15 species were recorded. The most commonly collected species were Aedes (Stegomyia) aegypti (L.) (n = 60,961) and Culex quinquefasciatus Say (45,702), which together accounted for 95.4% of the immatures collected. These species were commonly encountered during both rainy and dry seasons, whereas most other mosquito species were collected primarily during the rainy season. Other species collected were Aedes (Howardina) cozumelensis Diaz Najera, Aedes (Ochlerotatus) taeniorhynchus (Wiedemann), Aedes (Ochlerotatus) trivittatus (Coquillett), Culex coronator Dyar and Knab, Culex interrogator Dyar and Knab, Culex lactator Dyar and Knab, Culex nigripalpus Theobald, Culex salinarius Coquillett, Culex tarsalis Coquillett, Culex thriambus Dyar, Haemagogus equinus Theobald, Limatus durhamii Theobald, and Toxorhynchites rutilus (Coquillett). The greatest number of species was recorded from vacant lots (n = 11), followed by storm-water drains/catch basins (nine) and residential premises (six). Our study demonstrated that the heterogeneous urban environment in Mérida City supports a wide range of mosquito species, many of which are nuisance biters of humans and/or capable of serving as vectors of pathogens affecting humans or domestic animals. We also briefly reviewed the medical importance of the encountered mosquito species. PMID:25429168

  13. Bioaccumulation of organochlorine pollutants in the fish community in Lake Arungen, Norway.

    PubMed

    Sharma, Chhatra Mani; Rosseland, Bjřrn Olav; Almvik, Marit; Eklo, Ole Martin

    2009-01-01

    Organochlorine pollutants in the major fish species (pike Esox lucius, perch Perca fluviatilis, and roach Rutilus rutilus) of Lake Arungen, Norway, were investigated after an extensive removal of large pike in 2004. The organochlorine pollutants detected in fish liver samples in 2005 were dichlorodiphenyltrichloroethane (DDTs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and heptachlor epoxide (HCE). DDTs were the dominant among all analyzed OCs. Sigma PCB and HCB, detected in fish from two clearly distinct trophic levels (prey and predators), give an indication of biomagnification. All OC concentrations in female pike were significantly lower compared to males, which might be due to the removal of high concentrations of pollutants in roe during spawning. PMID:19329237

  14. Response of animal and vegetative cells to the effect of a typical magnetic storm

    NASA Astrophysics Data System (ADS)

    Talikina, M. G.; Izyumov, Yu. G.; Krylov, V. V.

    2013-12-01

    Experimentally reproduced fluctuations of a low-frequency magnetic field in a nanotesla range (magnetic storm) affect the mitosis of animals and vegetative cells. Action of this factor during twenty four hours leads to a significant increase in the proliferative activity of embryo cells in roach ( Rutilus rutilus L.) and meristem cells of onion rootlets ( Allium cepa). The clastogenic effect statistically confirmed only in the Allium test seems to reflect the species specificity of the response and higher sensitivity of the cell association of the onion meristem to magnetic storm.

  15. Fish assemblages in coastal lagoons in land-uplift succession: The relative importance of local and regional environmental gradients

    NASA Astrophysics Data System (ADS)

    Snickars, Martin; Sandström, Alfred; Lappalainen, Antti; Mattila, Johanna; Rosqvist, Kajsa; Urho, Lauri

    2009-01-01

    The assemblages of young-of-the-year fish were studied in coastal lagoons in an archipelago with post-glacial land-uplift, which affects environmental gradients at local and regional scale, i.e. lagoon habitat isolation and archipelago position, respectively. The categorisation of 40 undisturbed lagoons into nine habitat types based on habitat isolation and archipelago position was supported by clear relationships with spring temperature and total fish abundance. Rutilus rutilus, breams ( Abramis/Blicca sp.) and Perca fluviatilis were the most abundant and frequently occurring species. The fish assemblage differed among the nine habitat types. Rutilus rutilus, P. fluviatilis and breams were discriminating species in the majority of habitat types with low physical harshness, whereas Alburnus alburnus and Gasterosteus aculeatus increased their contributions in habitat types with high physical harshness. Rutilus rutilus and breams were thus common in lagoons with high habitat isolation situated in the inner archipelago. These lagoons were characterised by warm water and high vegetation coverage. Gasterosteus aculeatus was restricted to lagoons with low habitat isolation and exposure and low vegetation coverage, situated in the outer archipelago. Perca fluviatilis had the widest distribution of all species. The coverage of two macrophytes, Potamogeton perfoliatus and Zannichellia palustris, and salinity matched best the distance among habitat types. These habitat characteristics, as well as the fish abundances and assemblages differed most across the habitat types in the outer and mid archipelago zones and in the lowest habitat isolation. These patterns suggest that the structuring effect of habitat isolation increases along the archipelago gradient as differences between local and regional conditions increase. In the inner archipelago, overall low physical harshness induces homogeneous conditions and the habitat isolation is less important here than in the other zones. We suggest that this difference in the relative importance of the two gradients depending on the level of respective gradient ultimately forms these heterogeneous coastal habitats in a successional landscape. Rutilus rutilus and P. fluviatilis were responsible for large parts of the assemblage patterns. Although sympatric due to similar habitat requirements, differences in dispersal capability, competitive ability and predation vulnerability may add explanation to detected differences in distribution and abundance in these two species in an open system. Our results also stress the structuring role of vegetation in terms of total coverage and species composition, as these two aspects of macrophyte diversity may act as complementary habitat modifiers across gradients of physical harshness.

  16. Stunted growth of pikeperch Sander lucioperca in Lake Sahajärvi, Finland.

    PubMed

    Vinni, M; Lappalainen, J; Malinen, T; Lehtonen, H

    2009-03-01

    Growth of pikeperch Sander lucioperca in the eutrophic and clay-turbid Lake Sahajärvi, Southern Finland, was extremely slow in comparison with other lakes at similar latitudes. The most important food item in July was phantom midge larvae Chaoborus flavicans for all sizes of S. lucioperca (239-423 mm total length L(T)), while later, in August and September, the diet of S. lucioperca (149-407 mm L(T)) consisted of small (30-100 mm L(T)) perch Perca fluviatilis, ruffe Gymnocephalus cernuus and roach Rutilus rutilus. PMID:20735612

  17. Antioxidant activity of the mycelium of 21 wild mushroom species

    Microsoft Academic Search

    Fatih Kalyoncu; Mustafa Oskay; Hüsniye Kayalar

    2010-01-01

    In this study, the antioxidant activity of mycelia from 21 wild mushrooms – Agaricus bresadolanus, Auricularia auricula-judae, Chroogomphus rutilus, Fomes fomentarius, Ganoderma lucidum, Gloeophyllum trabeum, Gymnopus dryophilus, Infundibulicybe geotropa, Inocybe flocculosa var. crocifolia, Inocybe catalaunica, Lentinula edodes, Lentinus sajor-caju, Lycoperdon excipuliforme, Macrolepiota excoriata, Morchella esculenta var. rigida, Morchella intermedia, Omphalotus olearius, Pleurotus djamor, Postia stiptica, Rhizopogon roseolus and Stropharia inuncta

  18. REDESCRIPTIONS OF FIVE SPECIES OF THE FEATHER MITE GENUS Ptero- dectes ROBIN, 1877 (ACARI: PROCTOPHYLLODIDAE: PTERODECTINAE), WITH THE PROPOSAL OF A NEW GENUS AND A NEW SPECIES

    Microsoft Academic Search

    M. P. Valim; F. A. Hernandes; Rua Cristóvăo Colombo; Jardim Nazareth

    2008-01-01

    Five species of the feather mite genus Pterodectes Robin, 1877 are redescribed (type hosts are given in paren- thesis): Pterodectes rutilus Robin, 1868 (the Northern House-Martin, Delichon urbicum), P. crassus Trouessart, 1885 (the Plush- crested Jay, Cyanocorax chrysops), P. gracilis Trouessart, 1885 (the Crested Oropendola, Psarocolius decumanus), P. sialiarum (Stoll, 1893) (the Eastern Bluebird Sialia sialis) and P. muticus Banks,

  19. Aquat. Living Resour. 19, 115122 (2006) c EDP Sciences, IFREMER, IRD 2006

    E-print Network

    Guillard, Jean

    scales. This study represents the three dimensional description of juvenile fish schools (Perca fish species. Key words: Shoaling behaviour / 3-D structure / Sonar / Perca fluviatilis / Rutilus spatiales. Cette étude présente la description 3-D de bancs de juvéniles de perches et de gardons (Perca

  20. Historic hybridization and persistence of a novel mito-nuclear combination in red-backed voles (genus Myodes)

    Microsoft Academic Search

    Amy M Runck; Marjorie D Matocq; Joseph A Cook

    2009-01-01

    BACKGROUND: The role of hybridization in generating diversity in animals is an active area of discovery and debate. We assess hybridization across a contact zone of northern (Myodes rutilus) and southern (M. gapperi) red-backed voles using variation in skeletal features and both mitochondrial and nuclear loci. This transect extends approximately 550 km along the North Pacific Coast of North America

  1. [Effect of temperature on proteinase activities of enteral microbiota and intestinal mucosa of fish of different ecological group].

    PubMed

    Kuz'mina, V V; Shalygin, M V; Skvortsova, E G

    2012-01-01

    Effect of temperature on proteinases activities of enteral microbiota and of intestinal mucosa was studied in five fish species (roach Rutilus rutilus, crucian carp Carassius carassius, common perch Perca fluviatilis, pike-perch Zander lucioperca, and pike Esox lucius) belonging by the nutrition type to different ecological groups. Essential differences of temperature characteristics of proteinases of intestinal mucosa and of enteral microbiota are revealed in fish belonging by the nutrition type to different ecologic groups. The character of the t0-function of proteinases of intestinal mucosa and enteral microbiota by casein and hemoglobin as a rule is different. The highest values of relative proteinases activities for casein in the zone of low temperatures (38 and 45.3 % of the maximal activity) are found at study of proteinases of enteral microbiota in common perch and crucian carp. The latter indicates a significant adaptability of the enteral microbiota proteinases of common perch and crucial carp to functioning at low temperatures. PMID:22645973

  2. [Infection with opistorchis larvae in the fish family cyprinidae in the Ob-Irtysh River basin in the Tyumen region].

    PubMed

    2012-01-01

    Fishes, such as ide (Leuciscus idus), dace (Leuciscus leuciscus), carpbream (Abramis brama), roach (Rutilus rutilus), and muvarica (Alburnus alburnus), with different frequency and rate of invasion and abundance index were infested with larvae of O. felineus, M. bilis, and P. truncatum. There were the highest rates of fish infection with P. truncatum larvae in the subtaiga zone (the south of the region) and with O. felineus metacercariae in the northern subtaiga and taiga zones. In research, experimental, and clinical studies, the nosological entity opisthorchiasis is a parasitic cenosis consisting of 2-3 co-members requiring their specific identification, which allows therapeutic measures to be more effectively implemented among the population of a hyperendemic focus. PMID:23437717

  3. Host associations of the tick, Ixodes angustus (Acari: Ixodidae), on Alaskan mammals.

    PubMed

    Murrell, Brian P; Durden, Lance A; Cook, Joseph A

    2003-09-01

    Infestation parameters are presented for 227 ticks, all Ixodes angustus Neumann, collected from individual mammals (n = 531) in southeastern and south-central Alaska from 1996 to 1999. This tick was recovered from 12 of the 19 mammal species examined, with four species of shrews (Sorex spp.), two species of voles [Clethrionomys gapperi (Vigors) and Clethrionomys rutilus (Pallas)], one species of mouse [Peromyscus keeni (Rhoads)], and the red squirrel [Tamiasciurus hudsonicus (Erxleben)] being the most frequently parasitized hosts. Larvae (n = 146) of I. angustus were collected most often, followed by nymphs (n = 50), females (n = 30), and a single male. The leptinid mammal-nest beetle Leptinus occidentamericanus Peck (1 male, 5 females) was also recovered from five individual small mammals; three of these were C. rutilus. PMID:14596283

  4. Challenges in assessing biological recovery from acidification in Swedish lakes.

    PubMed

    Holmgren, Kerstin

    2014-01-01

    Since the 1980s, Swedish lakes have in general become less acidified. Assessment of biological recovery is, however, hampered by poor pre-acidification data, confounding effects of climate change, and few lakes with annual sampling of fish and other organisms. Only three critically acidified, but non-limed, lakes had two decades of fish monitoring. The lakes had not yet recovered to pre-industrial chemical targets. Fish had low species richness compared to other organism groups. Roach (Rutilus rutilus) and/or European perch (Perca fluviatilis) were the dominant fish species, and the acid-sensitive roach had been lost from one of the lakes. Calcium decreased, possibly approaching pre-acidification concentrations, but exceeded minimum levels needed to sustain some Daphnia species. High or increasing levels of total organic carbon, likely due to reduced acidification and climate change, might influence the biological communities in unexpected ways, for example, facilitating more frequent occurrence of the invasive algae Gonyostomum semen. PMID:25403967

  5. Contamination Levels and Specific Accumulation of Persistent Organochlorines in Caspian Seal ( Phoca caspica ) from the Caspian Sea, Russia

    Microsoft Academic Search

    M. Watanabe; S. Tanabe; R. Tatsukawa; M. Amano; N. Miyazaki; E. A. Petrov; S. L. Khuraskin

    1999-01-01

    .   Persistent organochlorines, such as polychlorinated biphenyls (PCBs) including coplanar congeners, DDTs, HCHs, chlordanes\\u000a (CHLs), and HCB, were determined in the blubber of Caspian seals (Phoca caspica) and their fish diet (Rutilus sp.) collected in 1993 from the northern Caspian Sea, Russia. Notable concentrations of DDTs and HCHs were found at mean\\u000a values of 19 and 1.3 ?g\\/g on wet-weight

  6. Population limitation of the northern red-backed vole in the boreal forests of northern Canada

    Microsoft Academic Search

    RUDY BOONSTRA

    2006-01-01

    Summary 1. Across the vast boreal forests of North America, no population cycles in Clethrion- omys species occur. In Eurasia, by contrast, some Clethrionomys populations of the same species undergo regular 3-5-year cycles. We examined the effects of nutrients, food, competitors, predators and climate on population limitation in the northern red-backed vole (Clethrionomys rutilus Pallas) in the south-western Yukon to

  7. Historical biogeography at the crossroads of the northern continents: molecular phylogenetics of red-backed voles (Rodentia: Arvicolinae).

    PubMed

    Cook, Joseph A; Runck, Amy M; Conroy, Chris J

    2004-03-01

    Evolutionary relationships of red-backed voles and their relatives were examined and used to test biogeographic hypotheses. Sequences of the mitochondrial cytochrome b gene were obtained for 25 individuals representing Alticola macrotis, Clethrionomys californicus, C. gapperi, C. glareolus, C. rutilus, and C. rufocanus. These were combined with 21 partial sequences from GenBank for C. regulus, C. rex, C. rufocanus, C. rutilus, Eothenomys imaizumii, E. melanogaster, Phaulomys andersoni, and P. smithii. Complete sequences of three species of Microtus (M. montanus, M. oeconomus, and M. pennsylvanicus), representative species of other arvicoline genera (Myopus, Synaptomys, Arvicola, Ellobius, Ondatra, Lemmus, Dicrostonyx, and Phenacomys), and a sigmodontine representative (Peromyscus) were included as outgroups. We used maximum parsimony, maximum likelihood, distance, and Bayesian based methods and conducted statistical tests on proposed hypotheses of phylogenetic relationships and biogeographic histories. A close relationship of species representing the genera Alticola, Clethrionomys, and Eothenomys was supported (Clethrionomyini); however, the genus Clethrionomys was paraphyletic with respect to both Alticola and Eothenomys. Three major clades were identified as Asian (Eothenomys andersoni, E. smithii, C. rex, C. regulus, and C. rufocanus), Trans-beringian (Alticola macrotis, C. californicus, C. gapperi, C. glarelolus, and C. rutilus), and Taiwanese (E. melanogaster). These results are consistent with the fossil record which indicates an initial diversification in Asia followed by colonization of the Nearctic on at least two occasions. The holarctic species, C. rutilus, appears to have either reinvaded Asia from North America or colonized North America more recently (late Pleistocene) than the two species of Clethrionomys (C. gapperi and C. californicus) that are endemic to North America (early to mid-Pleistocene). Finally, C. gapperi, appears to be comprised of an eastern and a western species, the former with affinities to the Asian C. glareolus and the latter more closely related to C. californicus. PMID:15012954

  8. Chromosome studies of European cyprinid fishes: interspecific homology of leuciscine cytotaxonomic marker-the largest subtelocentric chromosome pair as revealed by cross-species painting.

    PubMed

    Ráb, Petr; Rábová, Marie; Pereira, Carla Sofia; Collares-Pereira, Maria Joăo; Pelikánová, Sárka

    2008-01-01

    Leuciscine cyprinids possess a nearly invariant diploid number (2n = 50) with an extremely uniform karyotype comprising of 8 pairs of metacentric, 13-15 pairs of submetacentric and 2-4 pairs of subtelocentric (st) to acrocentric (a) chromosomes. The largest pair is characteristically an st/a element-the 'leuciscine' cytotaxonomic marker. Previously, the interspecific homology of this chromosome pair could not be assessed owing to the inability to produce euchromatic or serial banding patterns. In the present study, we used laser-microdissection (15-20 copies of the marker chromosome) to construct a whole chromosome probe (WCP) from the marker chromosome of the roach Rutilus rutilus to ascertain the interspecific homology of marker chromosomes by cross-species in-situ hybridization. WCP was hybridized to chromosomes of widely distributed (Abramis brama, Alburnoides bipunctatus, Alburnus alburnus, Aspius aspius, Ballerus ballerus, B. sapa, Blicca bjoerkna, Chondrostoma nasus, Leucaspius delineatus, Leuciscus leuciscus, L. idus, R. rutilus, Scardinius erythrophthalmus, Squalius cephalus, and Vimba vimba) and Iberian endemic species (Achondrostoma oligolepis, Iberochondrostoma almacai, I. lusitanicum, Pseudochondrostoma duriense, S. alburnoides and S. pyrenaicus). Cross-species in-situ hybridization to chromosomes of Phoxinus phoxinus, a representative of leuciscine sister lineage, showed the same pattern as in all of the leuciscins. The probe consistently hybridized to the distal part of the short arm of the marker chromosome, indicating sequence homology. PMID:18709543

  9. Additional treatment of wastewater reduces endocrine disruption in wild fish--a comparative study of tertiary and advanced treatments.

    PubMed

    Baynes, Alice; Green, Christopher; Nicol, Elizabeth; Beresford, Nicola; Kanda, Rakesh; Henshaw, Alan; Churchley, John; Jobling, Susan

    2012-05-15

    Steroid estrogens are thought to be the major cause of feminization (intersex) in wild fish. Widely used wastewater treatment technologies are not effective at removing these contaminants to concentrations thought to be required to protect aquatic wildlife. A number of advanced treatment processes have been proposed to reduce the concentrations of estrogens entering the environment. Before investment is made in such processes, it is imperative that we compare their efficacy in terms of removal of steroid estrogens and their feminizing effects with other treatment options. This study assessed both steroid removal and intersex induction in adult and early life stage fish (roach, Rutilus rutilus). Roach were exposed directly to either secondary (activated sludge process (ASP)), tertiary (sand filtrated (SF)), or advanced (chlorine dioxide (ClO(2)), granular activated charcoal (GAC)) treated effluents for six months. Surprisingly, both the advanced GAC and tertiary SF treatments (but not the ClO(2) treatment) significantly removed the intersex induction associated with the ASP effluent; this was not predicted by the steroid estrogen measurements, which were higher in the tertiary SF than either the GAC or the ClO(2). Therefore our study highlights the importance of using both biological and chemical analysis when assessing new treatment technologies. PMID:22500691

  10. The dependence on temperature and pH of the effects of zinc and copper on proteolytic activities of the digestive tract mucosa in piscivorous fish and their potential preys.

    PubMed

    Kuz'mina, V V; Ushakova, N V

    2010-09-01

    The dependence of the effects of zinc and copper on the activities of proteinases of the stomach and intestinal mucosa on temperature and pH in four species of boreal piscivorous fish (pike Esox lucius, zander Zander lucioperca, perch Perca fluviatilis and burbot Lota lota) as well as in some of their potential preys (kilka Clupeonella cultriventris, ruff Gymnocephalus cernuus, perch and roach Rutilus rutilus) was investigated. Species-specific differences of the effects of these heavy metals upon the activities of proteinases depending on temperature and pH were demonstrated. It was revealed that the stomach mucosa proteinases were more tolerant to the effects of the studied factors than the intestinal mucosa proteinases, especially true for pike. The effects of the heavy metals on the whole body proteinases of the fishes' potential preys were mostly dependent on temperature than on pH. At pH 3.0, the negative action of zinc and copper on the fish digestive tract mucosa proteolytic activity to a considerable degree was compensated by the high activity of the hemoglobinlytic proteinases, probably, cathepsine D. PMID:19731060

  11. Multiresidue method to quantify pesticides in fish muscle by QuEChERS-based extraction and LC-MS/MS.

    PubMed

    Lazartigues, Angélique; Wiest, Laure; Baudot, Robert; Thomas, Marielle; Feidt, Cyril; Cren-Olivé, Cécile

    2011-06-01

    Pesticide residues in fish muscle are an environmental and a health safety concern which requires analytical methods presenting high sensitivity and low limits of quantification. In this study, adapted QuEChERS method, coupled to liquid chromatography tandem mass spectrometry (Scheduled MRM-5500 QTRAP), was developed to quantify 13 pesticides (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl) in muscle of fish. Quantification limits were below 1 ng g(-1) except for clomazone (1.8 ng g(-1)) and quizalofop (7.4 ng g(-1)). Best recoveries were observed for perch (>80%) and roach (>68%), except for thifensulfuron-methyl. Lower recoveries had been observed for carp (6% to 86%). Relative standard deviation was lower than 28% for intra-day and 29% for inter-day analysis, respectively. This method was successfully tested on three fish species, naturally or orally exposed: roach (Rutilus rutilus), perch (Perca fluviatilis) and carp (Cyprinus carpio). Few levels were observed in fish naturally exposed, but carp and perch orally contaminated showed measurable levels in their muscles. PMID:21484246

  12. Hepatic and branchial glutathione S-transferases of two fish species: substrate specificity and biotransformation of microcystin-LR.

    PubMed

    Setlíková, I; Wiegand, C

    2009-05-01

    Liver and gills of roach (Rutilus rutilus) and silver carp (Hypophthalmichthys molitrix) were examined for glutathione S-transferases (GSTs) contents and their substrate specificity and capacity to biotransform microcystin-LR (MC-LR). GSTs and other glutathione (GSH) affine proteins were purified using a GSH-agarose matrix and separated by anionic chromatography (AEC). Substrate specificities were determined photometrical for 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB), 4-nitrobenzyl chloride (pNBC) and ethacrynic acid (ETHA). Biotransformation rate of MC-LR was determined by high performance liquid chromatography (HPLC). Roach exhibited different hepatic and branchial GST activities for used substrates (DNB, pNBC and DCNB) compared to silver carp but not for ethacrynic acid. It suggests that, both fish species have similar amount of pi and/or alpha class, which were the dominant GST classes in liver and gills. Gills of both fish species contained a higher number of GST isoenzymes, but with lower activities and ability of MC-LR biotransformation than livers. GST isoenzymes from roach had higher activity to biotransform MC-LR (conversion rate ranging up to 268 ng MC-LR min(-1) mL(-1) hepatic enzyme) than that isolated from silver carp. Without any prior contact to MC-LR or another GST inducer, roach seems to be better equipped for microcystin biotransformation than silver carp. PMID:19101655

  13. Differential Hepatic Metal and Metallothionein Levels in Three Feral Fish Species along a Metal Pollution Gradient

    PubMed Central

    Bervoets, Lieven; Knapen, Dries; De Jonge, Maarten; Van Campenhout, Karen; Blust, Ronny

    2013-01-01

    The accumulation of cadmium, copper and zinc and the induction of metallothioneins (MT) in liver of three freshwater fish species was studied. Gudgeon (Gobio gobio), roach (Rutilus rutilus) and perch (Perca fluviatilis) were captured at 6 sampling sites along a cadmium and zinc gradient and one reference site in a tributary of the Scheldt River in Flanders (Belgium). At each site up to 10 individuals per species were collected and analyzed on their general condition factor (K), hepatosomatic index (HSI) and gonadosomatic index (GSI). From each individual fish the liver was dissected and analyzed on Cd, Cu and Zn and MT-content. Although not all species were present at each site, hepatic Cd and Zn levels generally followed the pollution gradient and highest levels were measured in perch, followed by roach and gudgeon. Nevertheless also an effect of site was observed on this order. MT-levels appeared to be the highest in gudgeon although differences with the other species were not very pronounced and depended on the site. Significant relationships were found between hepatic zinc accumulation and MT levels. For each species the ratio MTtheoretical/ MTmeasured was calculated, which gives an indication of the relative capacity to induce MTs and thus immobilize the metals. Perch had the lowest capacity in inducing MTs (highest ratio). Relationships between hepatic metal levels and fish condition indices were absent or very weak. PMID:23556004

  14. Former uranium mine-induced effects in caged roach: a multiparametric approach for the evaluation of in situ metal toxicity.

    PubMed

    Gagnaire, Béatrice; Bado-Nilles, Anne; Betoulle, Stéphane; Amara, Rachid; Camilleri, Virginie; Cavalié, Isabelle; Chadili, Edith; Delahaut, Laurence; Kerambrun, Elodie; Orjollet, Daniel; Palluel, Olivier; Sanchez, Wilfried

    2015-01-01

    To characterize environmental risks linked to former uranium mines in the Limousin region of France, a study was conducted on fish health effects from uranium releases. Two private ponds were compared in this study, one with uranium contamination and one background site, upstream of the mining zone. Roach, Rutilus rutilus, were caged for 28 days in both ponds. Physico-chemical parameters of water and sediments and bioaccumulation of metals in several organs were determined. After 14 and 28 days of caging, immune, oxidative stress, biotransformation, neurotoxicity and physiological parameters were measured. Iron and aluminium were quantified in the water of both sites; however, barium and manganese were only present in the water of the uranium contaminated site. Uranium was present in both sites but at very different concentrations. The sediments from the uranium contaminated site contained high levels of radioactive elements coming from the disintegration chain of uranium. Results of biological parameters indicated stimulation of immune parameters and of oxidative stress and a decrease of AChE in fish caged in the uranium contaminated pond compared to the uranium-free pond. Overall, the results determined roach health status in the context of pollution from poly-metallic mining. The data strengthen our knowledge of the environmental risk assessment associated with radioactive substances in the environment. PMID:25348601

  15. Biology of Amur sleeper (Perccottus glehni) in the Delta of the Selenga River, Buryatia, Russia

    USGS Publications Warehouse

    Litvinov, Alexander G.; O'Gorman, Robert

    1996-01-01

    We determined the fecundity, growth, diet, and density of the Amur sleeper (Perccottus glehni) in the Selenga River Delta on Lake Baikal during 1986-1991 to better understand how this invading exotic will affect Baikal's endemic fishes. We also compared the Amur sleeper's diet with that of other fishes living in the delta. The largest Amur sleepers were about 200 mm long and weighed 200 g; the oldest were age 7. All females were mature at age 2. Fecundity ranged from 884 eggs at age 1 to 37,056 eggs at age 7. Highest densities of Amur sleepers were found in oxbow lakes where densities sometimes exceeded 4,000 fish per ha. The bulk of the diet of Amur sleeper age 2 and older was chironomids, fish, and fish eggs. Chironomids were also important in the diet of the commercially valuable Siberian roach (Rutilus rutilus lacustris) and Siberian dace (Leuciscus leuciscus baicalensis). Thus the Amur sleeper may cause population declines of these important endemic fishes through resource competition and predation on their juvenile life stages. However, Amur sleepers were the species of fish most frequently eaten by Eurasian perch (Perca fluviatilis) and northern pike (Esox lucius). So, maintaining vigorous populations of these two predators may well be an effective strategy for limiting the size of Amur sleeper populations.

  16. Shoreline development and degradation of coastal fish reproduction habitats.

    PubMed

    Sundblad, Göran; Bergström, Ulf

    2014-12-01

    Coastal development has severely affected habitats and biodiversity during the last century, but quantitative estimates of the impacts are usually lacking. We utilize predictive habitat modeling and mapping of human pressures to estimate the cumulative long-term effects of coastal development in relation to fish habitats. Based on aerial photographs since the 1960s, shoreline development rates were estimated in the Stockholm archipelago in the Baltic Sea. By combining shoreline development rates with spatial predictions of fish reproduction habitats, we estimated annual habitat degradation rates for three of the most common coastal fish species, northern pike (Esox lucius), Eurasian perch (Perca fluviatilis) and roach (Rutilus rutilus). The results showed that shoreline constructions were concentrated to the reproduction habitats of these species. The estimated degradation rates, where a degraded habitat was defined as having ?3 constructions per 100 m shoreline, were on average 0.5 % of available habitats per year and about 1 % in areas close to larger population centers. Approximately 40 % of available habitats were already degraded in 2005. These results provide an example of how many small construction projects over time may have a vast impact on coastal fish populations. PMID:24943864

  17. Hybridisation between two cyprinid fishes in a novel habitat: genetics, morphology and life-history traits

    PubMed Central

    2010-01-01

    Background The potential role hybridisation in adaptive radiation and the evolution of new lineages has received much recent attention. Hybridisation between roach (Rutilus rutilus L.) and bream (Abramis brama L.) is well documented throughout Europe, however hybrids in Ireland occur at an unprecedented frequency, often exceeding that of both parental species. Utilising an integrated approach, which incorporates geometric morphometrics, life history and molecular genetic analyses we identify the levels and processes of hybridisation present, while also determining the direction of hybridisation, through the analysis of mitochondrial DNA. Results The presence of F2 hybrids was found to be unlikely from the studied populations, although significant levels of backcrossing, involving both parental taxa was observed in some lakes. Hybridisation represents a viable conduit for introgression of genes between roach and bream. The vast majority of hybrids in all populations studied exhibited bream mitochondrial DNA, indicating that bream are maternal in the majority of crosses. Conclusions The success of roach × bream hybrids in Ireland is not due to a successful self reproducing lineage. The potential causes of widespread hybridisation between both species, along with the considerations regarding the role of hybridisation in evolution and conservation, are also discussed. PMID:20529364

  18. Roach, Sex, and Gender-Bending Chemicals: The Feminization of Wild Fish in English Rivers

    NSDL National Science Digital Library

    Charles Tyler, R. (University of Exeter - UK; )

    2008-12-01

    Feminization of the male roach, Rutilus rutilus, a freshwater, group-spawning fish, is widespread in English rivers; among the causative agents are natural and synthetic steroidal estrogens and chemicals that mimic estrogens. In feminized male roach, concentrations of the egg-yolk protein vitellogenin are elevated, sex steroid hormone dynamics are altered, and gonad development is disrupted (most notably, a female reproductive duct or developing eggs [oocytes] are present in the testis). In some English rivers containing high levels of estrogens, all male roach sampled have been feminized to varying degrees. In the more severely affected males, individuals produce low-quality sperm with a reduced capability for fertilization. Laboratory studies have shown that the environmental estrogens responsible for inducing gonadal feminization in roach can also alter reproductive behavior, disrupting normal breeding dynamics (parentage) in the zebrafish, another group-spawning fish. Together these findings indicate that feminization of wild roach may result in adverse population-level effects, but this hypothesis has yet to be fully addressed.

  19. Cross-species amplification of 41 microsatellites in European cyprinids: A tool for evolutionary, population genetics and hybridization studies

    PubMed Central

    2010-01-01

    Background Cyprinids display the most abundant and widespread species among the European freshwater Teleostei and are known to hybridize quite commonly. Nevertheless, a limited number of markers for conducting comparative differentiation, evolutionary and hybridization dynamics studies are available to date. Findings Five multiplex PCR sets were optimized in order to assay 41 cyprinid-specific polymorphic microsatellite loci (including 10 novel loci isolated from Chondrostoma nasus nasus, Chondrostoma toxostoma toxostoma and Leuciscus leuciscus) for 503 individuals (440 purebred specimens and 63 hybrids) from 15 European cyprinid species. The level of genetic diversity was assessed in Alburnus alburnus, Alburnoides bipunctatus, C. genei, C. n. nasus, C. soetta, C. t. toxostoma, L. idus, L. leuciscus, Pachychilon pictum, Rutilus rutilus, Squalius cephalus and Telestes souffia. The applicability of the markers was also tested on Abramis brama, Blicca bjoerkna and Scardinius erythrophtalmus specimens. Overall, between 24 and 37 of these markers revealed polymorphic for the investigated species and 23 markers amplified for all the 15 European cyprinid species. Conclusions The developed set of markers demonstrated its performance in discriminating European cyprinid species. Furthermore, it allowed detecting and characterizing hybrid individuals. These microsatellites will therefore be useful to perform comparative evolutionary and population genetics studies dealing with European cyprinids, what is of particular interest in conservation issues and constitutes a tool of choice to conduct hybridization studies. PMID:20478030

  20. The presence of EU priority substances mercury, hexachlorobenzene, hexachlorobutadiene and PBDEs in wild fish from four English rivers.

    PubMed

    Jürgens, Monika D; Johnson, Andrew C; Jones, Kevin C; Hughes, David; Lawlor, Alan J

    2013-09-01

    Since 2007 about 200 to 300 fish per year--generally roach (Rutilus rutilus) also a few bleak (Alburnus alburnus) and eels (Anguilla anguilla)--have been collected from a number of English river sites and stored at -80°C to build up a Fish Tissue Archive as a resource for the monitoring of pollutants. Some of the fish from the Fish Tissue Archive from the years 2007-2011 were analyzed for substances in current and proposed European legislation regarding environmental quality standards (EQS) in biota. It was found that mercury exceeded the EU EQS of 20 ?g/kg in 79% of samples with an average and median of 31 and 29 ?g/kg. The legacy fungicide hexachlorobenzene (HCB) was below the EQS of 10 ?g/kg in all fish analyzed, with a maximum of 6 ?g/kg in some eels. The legacy solvent hexachlorobutadiene (HCBD) was below the EQS of 55 ?g/kg, being <0.2 ?g/kg in all samples where it was measured. The sums of six polybrominated diphenyl ethers (PBDEs) were several orders of magnitude higher than the new proposed 0.0085 ?g/kg biota EQS. This study showed that the regular collection and analysis of whole body homogenate samples of relatively small native pelagic fish is suitable for the monitoring of contaminants capable of bioaccumulation. With regard to current or proposed EQS for EU countries, mercury and potentially PBDE in fish are of some concern in these English rivers. PMID:23747559

  1. Influence of the cestode Ligula intestinalis and the acanthocephalan Polymorphus minutus on levels of heat shock proteins (HSP70) and metallothioneins in their fish and crustacean intermediate hosts.

    PubMed

    Frank, Sabrina N; Godehardt, Saskia; Nachev, Milen; Trubiroha, Achim; Kloas, Werner; Sures, Bernd

    2013-09-01

    It is a common method to analyse physiological mechanisms of organisms - commonly referred to as biomarkers - to indicate the presence of environmental pollutants. However, as biomarkers respond to a wide range of stressors we want to direct the attention on natural stressors, i.e. on parasites. After two years maintenance under controlled conditions, roach (Rutilus rutilus) revealed no influence on levels of metallothionein by the parasite Ligula intestinalis. The same was found for Gammarus fossarum infected with Polymorphus minutus. However, the heat shock protein (HSP70) response was affected in both host-parasite systems. While the infection of roach resulted in reduced levels of HSP70 compared to uninfected roach, the infection in G. fossarum led to higher levels of HSP70. We also analysed the effect of a 14 days Cd exposure (4 ?g/L) on the uninfected and infected gammarids. The exposure resulted in induced levels for both, metallothionein and HSP70 whereas the combination of stressors, parasite and exposure, revealed a decrease for levels of HSP70 in comparison to the metal exposure only. Accordingly, parasites as natural parts of aquatic ecosystems have to be considered in ecotoxicological research. PMID:23770459

  2. Interactions between Predation and Resources Shape Zooplankton Population Dynamics

    PubMed Central

    Nicolle, Alice; Hansson, Lars-Anders; Brodersen, Jakob; Nilsson, P. Anders; Brönmark, Christer

    2011-01-01

    Identifying the relative importance of predation and resources in population dynamics has a long tradition in ecology, while interactions between them have been studied less intensively. In order to disentangle the effects of predation by juvenile fish, algal resource availability and their interactive effects on zooplankton population dynamics, we conducted an enclosure experiment where zooplankton were exposed to a gradient of predation of roach (Rutilus rutilus) at different algal concentrations. We show that zooplankton populations collapse under high predation pressure irrespective of resource availability, confirming that juvenile fish are able to severely reduce zooplankton prey when occurring in high densities. At lower predation pressure, however, the effect of predation depended on algal resource availability since high algal resource supply buffered against predation. Hence, we suggest that interactions between mass-hatching of fish, and the strong fluctuations in algal resources in spring have the potential to regulate zooplankton population dynamics. In a broader perspective, increasing spring temperatures due to global warming will most likely affect the timing of these processes and have consequences for the spring and summer zooplankton dynamics. PMID:21304980

  3. Migration confers survival benefits against avian predators for partially migratory freshwater fish

    PubMed Central

    Skov, Christian; Chapman, Ben B.; Baktoft, Henrik; Brodersen, Jakob; Brönmark, Christer; Hansson, Lars-Anders; Hulthén, Kaj; Nilsson, P. Anders

    2013-01-01

    The importance of predation risk in shaping patterns of animal migration is not well studied, mostly owing to difficulties in accurately quantifying predation risk for migratory versus resident individuals. Here, we present data from an extensive field study, which shows that migration in a freshwater fish (roach, Rutilus rutilus) that commonly migrates from lakes to streams during winter confers a significant survival benefit with respect to bird (cormorant, Phalacrocorax carbo spp.) predation. We tagged over 2000 individual fish in two Scandinavian lakes over 4 years and monitored migratory behaviour using passive telemetry. Next, we calculated the predation vulnerability of fish with differing migration strategies, by recovering data from passive integrated transponder tags of fish eaten by cormorants at communal roosts close to the lakes. We show that fish can reduce their predation risk from cormorants by migrating into streams, and that probability of being preyed upon by cormorants is positively related to the time individuals spend in the lake during winter. Our data add to the growing body of evidence that highlights the importance of predation for migratory dynamics, and, to our knowledge, is one of the first studies to directly quantify a predator avoidance benefit to migrants in the field. PMID:23445943

  4. Dietary effects on fatty acid composition in muscle tissue of juvenile European eel, Anguilla anguilla (L.)

    NASA Astrophysics Data System (ADS)

    Prigge, Enno; Malzahn, Arne M.; Zumholz, Karsten; Hanel, Reinhold

    2012-03-01

    The role of intracontinental migration patterns of European eel ( Anguilla anguilla) receives more and more recognition in both ecological studies of the European eel and possible management measures, but small-scale patterns proved to be challenging to study. We experimentally investigated the suitability of fatty acid trophic markers to elucidate the utilization of feeding habitats. Eight groups of juvenile European eels were fed on eight different diets in a freshwater recirculation system at 20°C for 56 days. Three groups were fed on freshwater diets ( Rutilus rutilus, Chironomidae larvae, and Gammarus pulex) and four groups were reared on diets of a marine origin ( Clupea harengus, Crangon crangon, Mysis spec., and Euphausia superba) and one on commercial pellets used in eel aquaculture. Fatty acid composition (FAC) of diets differed significantly with habitat. FAC of eel muscle tissue seemed to be rather insensitive to fatty acids supplied with diet, but the general pattern of lower n3:n6 and EPA:ARA ratios in freshwater prey organisms could be traced in the respective eels. Multivariate statistics of the fatty acid composition of the eels resulted in two distinct groups representing freshwater and marine treatments. Results further indicate the capability of selectively restraining certain fatty acids in eel, as e.g. the n3:n6 ratio in all treatments was <4, regardless of dietary n3:n6. In future studies on wild eel, these measures can be used to elucidate the utilization of feeding habitats of individual European eel.

  5. The impact of fish predation on shallow soft bottoms in brackish waters (SW Finland); an experimental study

    NASA Astrophysics Data System (ADS)

    Mattila, J.; Bonsdorff, E.

    The impact of fish predation on shallow soft bottoms was studied by field and laboratory experiments. The field manipulations (caging experiments) were carried out in 2 shallow (1.5 m) bays in the northern Baltic Sea. An a priori hypothesis that fish do not structure macrozoobenthic communities in shallow soft-bottom areas was tested. Short-term aquarium experiments clearly showed that perch ( Perca fluviatilis L.), roach ( Rutilus rutilus L.) and ruffe ( Acerina cernua (L.)) are all effective predators on benthic macroinvertebrates ( Corophium volutator) Pallas and Nereis diversicolor O.F. Müller) under laboratory conditions. Thus fish can be considered a potential structuring force on benthic communities in shallow soft-bottom areas. Caging experiments of one to two month's duration (partial and total exclosure of fish and enclosure with perch) induced only minor changes in the benthic community. These results support the a priori hypothesis. One of our main conclusions is, however, that fish predation and other biotic interactions (competition, disturbance, etc.) together with abiotic factors play some role in the structuring processes. Multilevel testing is needed in studies on biotic interactions in the marine environment. Results from a specific environment should not automatically be applied to other kinds of habitats.

  6. Distribution and Diet of 0+ Fish within a Canyon-Shaped European Reservoir in Late Summer

    NASA Astrophysics Data System (ADS)

    Vaek, Mojmír; Kubeka, Jan; Matna, Josef; Sea, Jaromír

    2006-05-01

    The distribution and diet of age 0+ fish were studied in the deep canyon-shaped ímov Reservoir (Czech Republic), which is characterized by a longitudinal trophic gradient. During late summer of two years, 0+ fish were sampled from inshore and offshore habitats along the longitudinal reservoir axis. Offshore catches of 0+ fish from the surface layer were dominated by roach (Rutilus rutilus ), bream (Abramis brama ) and perch (Perca fluviatilis ), whereas in the deeper open water perch predominated. Inshore catches of 0+ fish were constituted mainly by perch and roach. The proportions of roach in the inshore catches were highest at the upper and most eutrophic part of the reservoir, whereas the proportions of perch in the inshore catches were higher at the downstream areas. Total catches of both inshore and offshore 0+ fish increased upstream in the reservoir. Offshore 0+ perch were of consistently smaller size than inshore 0+ perch. Inshore 0+ perch had significantly smaller size at the upstream reservoir part than at the downstream, more lacustrine regions. The diet of both inshore and offshore 0+ fish consisted predominantly of crustacean zooplankton. Perch diet was generally dominated both by cladocerans and copepods, whereas roach diet consisted chiefly of cladocerans.

  7. Feeding habits and ontogenic changes in digestive enzyme patterns in five freshwater teleosts.

    PubMed

    Solovyev, M M; Kashinskaya, E N; Izvekova, G I; Gisbert, E; Glupov, V V

    2014-11-01

    Feeding habits and the activity of digestive enzymes (total alkaline proteases, ?-amylase and lipase) from dace Leuciscus leuciscus, roach Rutilus rutilus, Prussian carp Carassius auratus gibelio, perch Perca fluviatilis and pikeperch Sander lucioperca fry were studied in the Malye Chany Lake-Kargat Estuary (western Siberia, Russia). The diet of fry from all studied species was mainly composed of chironomid larvae and zooplanktonic organisms (i.e. cladocera and copepoda), whereas carnivorous species such as P. fluviatilis and S. lucioperca also preyed on fry from other fishes while detritus and microalgae were also important in the diet of ommivorous species. When comparing diet similarity (Sřrensen-Dice index, Q(S)) among fry at different stages of development, both omnivorous and carnivorous species showed a high level of similarity (0.67?

  8. The Consequences of Feminization in Breeding Groups of Wild Fish

    PubMed Central

    Harris, Catherine A.; Hamilton, Patrick B.; Runnalls, Tamsin J.; Vinciotti, Veronica; Henshaw, Alan; Hodgson, Dave; Coe, Tobias S.; Jobling, Susan; Tyler, Charles R.; Sumpter, John P.

    2011-01-01

    Background The feminization of nature by endocrine-disrupting chemicals (EDCs) is a key environmental issue affecting both terrestrial and aquatic wildlife. A crucial and as yet unanswered question is whether EDCs have adverse impacts on the sustainability of wildlife populations. There is widespread concern that intersex fish are reproductively compromised, with potential population-level consequences. However, to date, only in vitro sperm quality data are available in support of this hypothesis. Objective The aim of this study was to examine whether wild endocrine-disrupted fish can compete successfully in a realistic breeding scenario. Methods In two competitive breeding experiments using wild roach (Rutilus rutilus), we used DNA microsatellites to assign parentage and thus determine reproductive success of the adults. Results In both studies, the majority of intersex fish were able to breed, albeit with varying degrees of success. In the first study, where most intersex fish were only mildly feminized, body length was the only factor correlated with reproductive success. In the second study, which included a higher number of more severely intersex fish, reproductive performance was negatively correlated with severity of intersex. The intersex condition reduced reproductive performance by up to 76% for the most feminized individuals in this study, demonstrating a significant adverse effect of intersex on reproductive performance. Conclusion Feminization of male fish is likely to be an important determinant of reproductive performance in rivers where there is a high prevalence of moderately to severely feminized males. PMID:21362587

  9. Use Carum copticum essential oil for controlling the Listeria monocytogenes growth in fish model system.

    PubMed

    Rabiey, Soghra; Hosseini, Hedayat; Rezaei, Masoud

    2014-01-01

    This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 °C for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths. PMID:24948918

  10. Use Carum copticum essential oil for controlling the Listeria monocytogenes growth in fish model system

    PubMed Central

    Rabiey, Soghra; Hosseini, Hedayat; Rezaei, Masoud

    2014-01-01

    This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 °C for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths. PMID:24948918

  11. Biomonitoring of polychlorinated biphenyls (PCBs) in heavily polluted aquatic environment in different fish species.

    PubMed

    Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana; Šalgovi?ová, Danka; Tur?eková, L'udmila

    2012-11-01

    The distribution and concentrations of polychlorinated biphenyls (PCBs) were determined in fish species (European perch Perca fluviatilis, northern pike Esox lucius, pike perch Sander lucioperca, wels catfish Silirus glanus, common carp Cyprinus carpio, European eel Anguilla anguilla, freshwater bream Abramis brama, goldfish Carassius auratus, and roach Rutilus rutilus) in a heavily polluted water reservoir Zemplínska šírava (Slovakia). The study performed at two different time points 5 years apart (2004 and 2009) revealed serious PCB contamination of fish muscle tissue and significant interspecies as well as tissue-specific differences in PCB uptake by fish. Total PCBs broadly correlated with the trophic position of individual fish species within a food chain (P < 0.01). The concentrations were particularly high in predatory fish species, perch, pike, and pike perch (108.0, 90.1, and 113.0 mg kg(-1) lipid wt, respectively), but comparable PCB values were also found in non-predatory detrivorous freshwater bream (128.0 mg kg(-1) lipid wt). The lowest PCB values were surprisingly assessed in European eel (17.1 mg kg(-1) lipid wt). Tissue analysis showed the highest storage capacity of the liver (hepatopancreas in cyprinids) with maximum concentrations recorded found in northern pike (214.0 mg kg(-1) lipid wt) and freshwater bream (163.0 mg kg(-1) lipid wt). Negative correlations, mostly not significant, between the total PCB concentrations and fish weight were observed (P > 0.05). The study has shown that the kind of fish, its feeding habit, and specific conditions of the habitat are mutually interrelated factors that are responsible for significant variations in fish body burdens. A tendency to PCB biomagnification was also proved in some fish species of this water reservoir. PMID:22173787

  12. Transferability of predictive fish distribution models in two coastal systems

    NASA Astrophysics Data System (ADS)

    Sundblad, Göran; Härmä, Meri; Lappalainen, Antti; Urho, Lauri; Bergström, Ulf

    2009-06-01

    Species distribution modelling has emerged as a tool both for exploring niche theory and for producing distribution maps for management. To understand and predict potential effects of large scale habitat change there is a need for proper model validation and applicability also in unstudied areas. However, knowledge about factors influencing the transferability of distribution models, i.e. the accuracy of the models when applying them in a new geographical area, is limited. We have successfully modelled the larval distribution of two fish species, northern pike ( Esox lucius L.) and roach ( Rutilus rutilus L.), on a regional scale in the Baltic Sea using a few and easily measured environmental variables. When models were transferred from the training area to the testing area the models showed reasonable to very good discrimination (ROC 0.75 and 0.93) based on external validation using independent data separated also in time (1-2 years). The predicted larval distribution also overlapped with the distribution of young-of-the-year fish later in the season. Performance when reversing the transfer, by constructing the models in the testing area and predicting back to the original training area, was less successful. This discrepancy was species-specific and could be explained by differences in the species presence ranges along the predictor variables in the testing area compared to the training area. Our results illustrate how transferability success can be influenced by area-specific differences in the range of the predictor variables and show the necessity of validating model predictions properly.

  13. Metals in edible fish from Vistula River and Dead Vistula River channel, Baltic Sea.

    PubMed

    Wyrzykowska, Barbara; Falandysz, Jerzy; Jarzy?ska, Gra?yna

    2012-01-01

    Metals including Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sr and Zn were determined in muscle tissue of 12 fish species by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and cold vapour-atomic absorption spectroscopy (CV-AAS). Fish were collected from Vistula River at lower course and Dead Vistula River channel in south of Baltic Sea in Poland. The fish species examined include Round Goby (Neogobius melanostomus), Crucian Carp (Carassius carassius), Bull-rout (Myoxocephalus scorpius), Tench (Tinca tinca), Bream (Abramis brama), Burbot (Lota lot), Perch (Perca perca), Roach (Rutilus rutilus), Silver Carp (Hypophthalmichthys molitrix), Pikeperch (Stizostediun lucioperca), Brown salmon (Salmo trutta m. Trutta) and Eel (Anguilla anguilla). The median values of metal concentrations in fresh muscle tissue of 11 fish species varied as follows: Al < 0.5-60; Ba < 0.05-0.31; Ca 120-1800; Cd < 0.05-0.096; Co < 0.10; Cr < 0.10-0.50; Cu < 0.15-0.77; Fe 1.5-21; Hg 0.0058-0.65; K 1800-4200; Mg 130-560; Mn 0.12-0.59; Na 350-840; Ni < 0.2-0.31; Pb < 0.75; Sr 0.079-2.9; Zn 3.3-23 ?g/g fresh weight. The Target Hazard Quotient (THQ) values calculated in this study for Cd and Hg from muscles of fish species collected from Vistula River were low in the range of 0.4 for Hg and 0.8 for Cd. PMID:22428891

  14. Piscivore-Prey Fish Interactions: Mechanisms behind Diurnal Patterns in Prey Selectivity in Brown and Clear Water

    PubMed Central

    Ranĺker, Lynn; Persson, Jens; Jönsson, Mikael; Nilsson, P. Anders; Brönmark, Christer

    2014-01-01

    Environmental change may affect predator-prey interactions in lakes through deterioration of visual conditions affecting foraging success of visually oriented predators. Environmental change in lakes includes an increase in humic matter causing browner water and reduced visibility, affecting the behavioural performance of both piscivores and prey. We studied diurnal patterns of prey selection in piscivorous pikeperch (Sander lucioperca) in both field and laboratory investigations. In the field we estimated prey selectivity and prey availability during day and night in a clear and a brown water lake. Further, prey selectivity during day and night conditions was studied in the laboratory where we manipulated optical conditions (humic matter content) of the water. Here, we also studied the behaviours of piscivores and prey, focusing on foraging-cycle stages such as number of interests and attacks by the pikeperch as well as the escape distance of the prey fish species. Analyses of gut contents from the field study showed that pikeperch selected perch (Perca fluviatilis) over roach (Rutilus rutilus) prey in both lakes during the day, but changed selectivity towards roach in both lakes at night. These results were corroborated in the selectivity experiments along a brown-water gradient in day and night light conditions. However, a change in selectivity from perch to roach was observed when the optical condition was heavily degraded, from either brown-stained water or light intensity. At longer visual ranges, roach initiated escape at distances greater than pikeperch attack distances, whereas perch stayed inactive making pikeperch approach and attack at the closest range possible. Roach anti-predatory behaviour decreased in deteriorated visual conditions, altering selectivity patterns. Our results highlight the importance of investigating both predator and prey responses to visibility conditions in order to understand the effects of degrading optical conditions on piscivore-prey interaction strength and thereby ecosystem responses to brownification of waters. PMID:25379665

  15. How well can fishes prey on zebra mussels in eastern North America?

    USGS Publications Warehouse

    French, John R. P., III

    1993-01-01

    Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations or drum, sunfishes, and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

  16. Differences in the Activities of Eight Enzymes from Ten Soil Fungi and Their Possible Influences on the Surface Structure, Functional Groups, and Element Composition of Soil Colloids

    PubMed Central

    Wang, Wenjie; Li, Yanhong; Wang, Huimei; Zu, Yuangang

    2014-01-01

    How soil fungi function in soil carbon and nutrient cycling is not well understood by using fungal enzymatic differences and their interactions with soil colloids. Eight extracellular enzymes, EEAs (chitinase, carboxymethyl cellulase, ?-glucosidase, protease, acid phosphatase, polyphenol oxidase, laccase, and guaiacol oxidase) secreted by ten fungi were compared, and then the fungi that showed low and high enzymatic activity were co-cultured with soil colloids for the purpose of finding fungi-soil interactions. Some fungi (Gomphidius rutilus, Russula integra, Pholiota adiposa, and Geastrum mammosum) secreted 3–4 enzymes with weak activities, while others (Cyathus striatus, Suillus granulate, Phallus impudicus, Collybia dryophila, Agaricus sylvicola, and Lactarius deliciosus) could secret over 5 enzymes with high activities. The differences in these fungi contributed to the alterations of functional groups (stretching bands of O-H, N-H, C-H, C?=?O, COO- decreased by 11–60%, while P?=?O, C-O stretching, O-H bending and Si-O-Si stretching increased 9–22%), surface appearance (disappearance of adhesive organic materials), and elemental compositions (11–49% decreases in C1s) in soil colloids. Moreover, more evident changes were generally in high enzymatic fungi (C. striatus) compared with low enzymatic fungi (G. rutilus). Our findings indicate that inter-fungi differences in EEA types and activities might be responsible for physical and chemical changes in soil colloids (the most active component of soil matrix), highlighting the important roles of soil fungi in soil nutrient cycling and functional maintenance. PMID:25398013

  17. Evaluation of spatial distribution and accumulation of novel brominated flame retardants, HBCD and PBDEs in an Italian subalpine lake using zebra mussel (Dreissena polymorpha).

    PubMed

    Poma, Giulia; Binelli, Andrea; Volta, Pietro; Roscioli, Claudio; Guzzella, Licia

    2014-08-01

    Because of the reduction in the use of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD), novel brominated flame retardants (NBFRs), including 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), and pentabromoethylbenzene (PBEB), started to be marketed as alternatives to the banned formulations. In this study, the spatial distribution and accumulation of NBFRs, PBDEs, and HBCD in the biota have been investigated in the littoral compartment of a large and deep subalpine lake (Lake Maggiore, Northern Italy), using zebra mussel Dreissena polymorpha and roach (Rutilus rutilus) as bioindicators. To our knowledge, this is the first study reporting the contamination of NBFRs in the freshwater invertebrate D. polymorpha. Contamination of zebra mussel due to PBEB, HBB, and BTBPE was low, ranging from 0.9 to 2.9 ng/g lipid weight, from 1.1 to 2.9 ng/g l.w., and from 3.5 to 9.5 ng/g l.w., respectively. PBEB and BTBPE in roach were always below the detection limit, while the contamination of HBB ranged from < limits of detection (LOD) to 1.74 ng/g l.w., indicating a weak contamination. DBDPE was < LOD in all the considered biological samples. Finally, HBCD was detected in all organic tissues with mean concentrations up to 74.4 ng/g l.w. PBDE results, supported by principal component analysis elaboration, suggested a possible contamination due to the congeners composing the penta- and deca-BDE technical formulations, which are present in the Lake Maggiore basin. The biomagnification factor values showed that tetra- and penta-BDE biomagnified, while octa-, nona-, and deca-BDE were still bioavailable and detectable in the fish muscles, but they do not biomagnified. Considering the other BFRs, only HBCD showed a moderate biomagnification potential. PMID:24756669

  18. Effects of primary- and secondary-treated bleached kraft mill effluents on the immune system and physiological parameters of roach.

    PubMed

    Aaltonen, T M; Jokinen, E I; Lappivaara, J; Markkula, S E; Salo, H M; Leppänen, H; Lammi, R

    2000-11-01

    The present study was designed to examine, whether, effluents from a modern pulp and paper mill using elemental chlorine-free/total chlorine-free (ECF/TCF) bleaching, exert effects on the immune system of fish and, in addition, to relate these findings to physiological parameters known to be affected by bleached kraft-mill effluents (BKME). Roach (Rutilus rutilus) were exposed in laboratory conditions to primary- or secondary-treated effluent from a pulp and paper mill. In order to study their capability to respond to foreign antigens they were immunised with bovine gamma-globulin (BGG) prior to exposure. The number of anti-BGG antibody-secreting cells (ASC) and the number of immunoglobulin-secreting cells (ISC) in the spleen and blood as well as the level of anti-BGG specific antibodies and concentration of plasma immunoglobulin (IgM) were studied. Phagocytosis and migration of granulocytes of the head kidney were also determined. In addition to the immunological parameters, the activity of hepatic biotransformation enzymes, the carbohydrate metabolism and osmoregulation were examined. Exposure of roach for 21 days to BKME affected several immunological parameters. Both effluents, primary- and secondary-treated, impaired the immunoreactivity of the fish. Sex-related differences in the immune responses were evident in many parameters e.g. in the number of blood ISC and splenic ASC. Sex also had effects on cortisol levels and in the induction of 7-ethoxyresorufin O-deethylase (EROD). These results demonstrate that both primary- and secondary-treated effluent from a pulp and paper mill using ECF/TCF bleaching have effects on fish immune functions. Further, these findings suggest that steroids may contribute to immunomodulation in fish. PMID:10998499

  19. Temperature and Resource Availability May Interactively Affect Over-Wintering Success of Juvenile Fish in a Changing Climate

    PubMed Central

    Brodersen, Jakob; Rodriguez-Gil, José Luis; Jönsson, Mikael; Hansson, Lars-Anders; Brönmark, Christer; Nilsson, P. Anders; Nicolle, Alice; Berglund, Olof

    2011-01-01

    The predicted global warming may affect freshwater systems at several organizational levels, from organism to ecosystem. Specifically, in temperate regions, the projected increase of winter temperatures may have important effects on the over-winter biology of a range of organisms and especially for fish and other ectothermic animals. However, temperature effects on organisms may be directed strongly by resource availability. Here, we investigated whether over-winter loss of biomass and lipid content of juvenile roach (Rutilus rutilus) was affected by the physiologically relatively small (2-5°C) changes of winter temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), under both natural and experimental conditions. This was investigated in combination with the effects of food availability. Finally, we explored the potential for a correlation between lake temperature and resource levels for planktivorous fish, i.e., zooplankton biomass, during five consecutive winters in a south Swedish lake. We show that small increases in temperature (+2°C) affected fish biomass loss in both presence and absence of food, but negatively and positively respectively. Temperature alone explained only a minor part of the variation when food availability was not taken into account. In contrast to other studies, lipid analyses of experimental fish suggest that critical somatic condition rather than critical lipid content determined starvation induced mortality. Our results illustrate the importance of considering not only changes in temperature when predicting organism response to climate change but also food-web interactions, such as resource availability and predation. However, as exemplified by our finding that zooplankton over-winter biomass in the lake was not related to over-winter temperature, this may not be a straightforward task. PMID:21998627

  20. Temperature and resource availability may interactively affect over-wintering success of juvenile fish in a changing climate.

    PubMed

    Brodersen, Jakob; Rodriguez-Gil, José Luis; Jönsson, Mikael; Hansson, Lars-Anders; Brönmark, Christer; Nilsson, P Anders; Nicolle, Alice; Berglund, Olof

    2011-01-01

    The predicted global warming may affect freshwater systems at several organizational levels, from organism to ecosystem. Specifically, in temperate regions, the projected increase of winter temperatures may have important effects on the over-winter biology of a range of organisms and especially for fish and other ectothermic animals. However, temperature effects on organisms may be directed strongly by resource availability. Here, we investigated whether over-winter loss of biomass and lipid content of juvenile roach (Rutilus rutilus) was affected by the physiologically relatively small (2-5 °C) changes of winter temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), under both natural and experimental conditions. This was investigated in combination with the effects of food availability. Finally, we explored the potential for a correlation between lake temperature and resource levels for planktivorous fish, i.e., zooplankton biomass, during five consecutive winters in a south Swedish lake. We show that small increases in temperature (+2 °C) affected fish biomass loss in both presence and absence of food, but negatively and positively respectively. Temperature alone explained only a minor part of the variation when food availability was not taken into account. In contrast to other studies, lipid analyses of experimental fish suggest that critical somatic condition rather than critical lipid content determined starvation induced mortality. Our results illustrate the importance of considering not only changes in temperature when predicting organism response to climate change but also food-web interactions, such as resource availability and predation. However, as exemplified by our finding that zooplankton over-winter biomass in the lake was not related to over-winter temperature, this may not be a straightforward task. PMID:21998627

  1. Mercury content in the trophic chain of the Tanew River, Poland, ecosystem.

    PubMed

    Wa?kuska, Grazyna; Cha?abis-Mazurek, Agnieszka; Szkoda, Józef

    2010-01-01

    Mercury (Hg) is a highly toxic metal posing a hazard to water ecosystems. This investigation was aimed at determining Hg content in the Tanew River, Poland, and subsequent transfer to fish inhabiting this lake. The area studied included approximately a 50-km distance of the river, with 5 sampling locations selected. Samples of water and bottom sediments were collected from 10 sites along the river-bank zone for each location. At the same location, fish were caught and samples of coastal water plants were collected. Fish that were caught included the following species: chub (Leuciscus cephalus), pike (Esox lucius), ide (Leuciscus idus), and roach (Rutilus rutilus). Dominanting species of water plants included reed-mace (Typha angustifolia), rigid hornwort (Ceratophyllum demersum), and water knotweed (Polygonum amphibium). Mercury content in samples of water, bottom sediments, water plants, and fish tissues (muscles and gills) were determined by using a Mercury/MA-2000 system (NIC, Japan). The average Hg content in the waters of Tanew ranged between 1 and 5 microg/L, and in the bottom sediments ranged between 17 and 214 microg/kg dry weight, which are characteristic values for typical unpolluted areas. The highest Hg contamination of waters and bottom sediments was found where the Tanew estuary enters the San River. Mercury levels in fish from the Tanew delta appeared to be higher compared to other sampling sites. Data indicated that even if water environment is contaminated with Hg to a limited extent, fish accumulate this metal at higher levels, probably due to a bioaccumulation or bioconcentration factor. PMID:20706942

  2. Piscivore-prey fish interactions: mechanisms behind diurnal patterns in prey selectivity in brown and clear water.

    PubMed

    Ranĺker, Lynn; Persson, Jens; Jönsson, Mikael; Nilsson, P Anders; Brönmark, Christer

    2014-01-01

    Environmental change may affect predator-prey interactions in lakes through deterioration of visual conditions affecting foraging success of visually oriented predators. Environmental change in lakes includes an increase in humic matter causing browner water and reduced visibility, affecting the behavioural performance of both piscivores and prey. We studied diurnal patterns of prey selection in piscivorous pikeperch (Sander lucioperca) in both field and laboratory investigations. In the field we estimated prey selectivity and prey availability during day and night in a clear and a brown water lake. Further, prey selectivity during day and night conditions was studied in the laboratory where we manipulated optical conditions (humic matter content) of the water. Here, we also studied the behaviours of piscivores and prey, focusing on foraging-cycle stages such as number of interests and attacks by the pikeperch as well as the escape distance of the prey fish species. Analyses of gut contents from the field study showed that pikeperch selected perch (Perca fluviatilis) over roach (Rutilus rutilus) prey in both lakes during the day, but changed selectivity towards roach in both lakes at night. These results were corroborated in the selectivity experiments along a brown-water gradient in day and night light conditions. However, a change in selectivity from perch to roach was observed when the optical condition was heavily degraded, from either brown-stained water or light intensity. At longer visual ranges, roach initiated escape at distances greater than pikeperch attack distances, whereas perch stayed inactive making pikeperch approach and attack at the closest range possible. Roach anti-predatory behaviour decreased in deteriorated visual conditions, altering selectivity patterns. Our results highlight the importance of investigating both predator and prey responses to visibility conditions in order to understand the effects of degrading optical conditions on piscivore-prey interaction strength and thereby ecosystem responses to brownification of waters. PMID:25379665

  3. Assessing anthropogenic impact on boreal lakes with historical fish species distribution data and hydrogeochemical modeling

    PubMed Central

    Valinia, Salar; Englund, Göran; Moldan, Filip; Futter, Martyn N; Köhler, Stephan J; Bishop, Kevin; Fölster, Jens

    2014-01-01

    Quantifying the effects of human activity on the natural environment is dependent on credible estimates of reference conditions to define the state of the environment before the onset of adverse human impacts. In Europe, emission controls that aimed at restoring ecological status were based on hindcasts from process-based models or paleolimnological reconstructions. For instance, 1860 is used in Europe as the target for restoration from acidification concerning biological and chemical parameters. A more practical problem is that the historical states of ecosystems and their function cannot be observed directly. Therefore, we (i) compare estimates of acidification based on long-term observations of roach (Rutilus rutilus) populations with hindcast pH from the hydrogeochemical model MAGIC; (ii) discuss policy implications and possible scope for use of long-term archival data for assessing human impacts on the natural environment and (iii) present a novel conceptual model for interpreting the importance of physico-chemical and ecological deviations from reference conditions. Of the 85 lakes studied, 78 were coherently classified by both methods. In 1980, 28 lakes were classified as acidified with the MAGIC model, however, roach was present in 14 of these. In 2010, MAGIC predicted chemical recovery in 50% of the lakes, however roach only recolonized in five lakes after 1990, showing a lag between chemical and biological recovery. Our study is the first study of its kind to use long-term archival biological data in concert with hydrogeochemical modeling for regional assessments of anthropogenic acidification. Based on our results, we show how the conceptual model can be used to understand and prioritize management of physico-chemical and ecological effects of anthropogenic stressors on surface water quality. PMID:24535943

  4. Populations of a cyprinid fish are self-sustaining despite widespread feminization of males

    PubMed Central

    2014-01-01

    Background Treated effluents from wastewater treatment works can comprise a large proportion of the flow of rivers in the developed world. Exposure to these effluents, or the steroidal estrogens they contain, feminizes wild male fish and can reduce their reproductive fitness. Long-term experimental exposures have resulted in skewed sex ratios, reproductive failures in breeding colonies, and population collapse. This suggests that environmental estrogens could threaten the sustainability of wild fish populations. Results Here we tested this hypothesis by examining population genetic structures and effective population sizes (Ne) of wild roach (Rutilus rutilus L.) living in English rivers contaminated with estrogenic effluents. Ne was estimated from DNA microsatellite genotypes using approximate Bayesian computation and sibling assignment methods. We found no significant negative correlation between Ne and the predicted estrogen exposure at 28 sample sites. Furthermore, examination of the population genetic structure of roach in the region showed that some populations have been confined to stretches of river with a high proportion of estrogenic effluent for multiple generations and have survived, apparently without reliance on immigration of fish from less polluted sites. Conclusions These results demonstrate that roach populations living in some effluent-contaminated river stretches, where feminization is widespread, are self-sustaining. Although we found no evidence to suggest that exposure to estrogenic effluents is a significant driving factor in determining the size of roach breeding populations, a reduction in Ne of up to 65% is still possible for the most contaminated sites because of the wide confidence intervals associated with the statistical model. PMID:24417977

  5. Epidemiology of fishborne trematodiasis in Kazakhstan.

    PubMed

    Sultanov, A; Abdybekova, A; Abdibaeva, A; Shapiyeva, Z; Yeshmuratov, T; Torgerson, P R

    2014-10-01

    Fish borne trematodes are an important cause of morbidity in Kazakhstan. The number of human cases of opisthorchiidosis (infection with parasites of the family opisthorchiidae) reached a peak of 2521 recorded cases (17 cases per 100,000) in 2002 with a gradual decline to 1225 cases (7.4 cases per 100,000) in 2011. Most human cases are found in the north and north east part of Kazakhstan in areas drained by the Irtysh River and it tributaries. A further focus is found in the north west in the Ural river basin in the European part of Kazakhstan. The most common occupations of patients with opisthorchiidosis included the manual laborers, those employed in the home or unemployed. Necropsy investigations of village dogs in an endemic region revealed 37 of 51 (72%) village dogs infected with either Opisthorchis felineus or Methorchis bilis. Likewise an investigation of 242 cats consisting of strays, village, suburban and city cats revealed 79 (33%) animals infected with O. felineus. Higher prevalences were seen in strays and village cats compared to suburban cats. No urban cats, which lived in apartments, were found to be infected. Other important zoonoses included Echinococcus granulosus, detected in 2 of the 51 necropsied village dogs and E. multilocularis was found in 2 out of 124 necropsied stray cats. Investigations of locally caught fish revealed 10 of 107 (9%) roach (Rutilus rutilus), 49 of 68(72%) ide (Leuciscus idus) and 2 of 79 (2.5%) bream (Abramis brama) infested with trematode metacercariae. No metacercariae were found in 609 crucian carp (Carassius carassius), 35 tench (Tinca tinca), 79 carp (Cyprinus carpio), 46 perch (Perca fluviatilis) or 20 zander (Sander lucioperca). PMID:24943190

  6. An evaluation of LSU rDNA D1-D2 sequences for their use in species identification

    PubMed Central

    Sonnenberg, Rainer; Nolte, Arne W; Tautz, Diethard

    2007-01-01

    Background Identification of species via DNA sequences is the basis for DNA taxonomy and DNA barcoding. Currently there is a strong focus on using a mitochondrial marker for this purpose, in particular a fragment from the cytochrome oxidase I gene (COI). While there is ample evidence that this marker is indeed suitable across a broad taxonomic range to delineate species, it has also become clear that a complementation by a nuclear marker system could be advantageous. Ribosomal RNA genes could be suitable for this purpose, because of their global occurrence and the possibility to design universal primers. However, it has so far been assumed that these genes are too highly conserved to allow resolution at, or even beyond the species level. On the other hand, it is known that ribosomal gene regions harbour also highly divergent parts. We explore here the information content of two adjacent divergence regions of the large subunit ribosomal gene, the D1-D2 region. Results Universal primers were designed to amplify the D1-D2 region from all metazoa. We show that amplification products in the size between 800–1300 bp can be obtained across a broad range of animal taxa, provided some optimizations of the PCR procedure are implemented. Although the ribosomal genes occur in multiple copies in the genomes, we find generally very little intra-individual polymorphism (<< 0.1% on average) indicating that concerted evolution is very effective in most cases. Studies in two fish taxa (genus Cottus and genus Aphyosemion) show that the D1-D2 LSU sequence can resolve even very closely related species with the same fidelity as COI sequences. In one case we can even show that a mitochondrial transfer must have occurred, since the nuclear sequence confirms the taxonomic assignment, while the mitochondrial sequence would have led to the wrong classification. We have further explored whether hybrids between species can be detected with the nuclear sequence and we show for a test case of natural hybrids among cyprinid fish species (Alburnus alburnus and Rutilus rutilus) that this is indeed possible. Conclusion The D1-D2 LSU region is a suitable marker region for applications in DNA based species identification and should be considered to be routinely used as a marker complementing broad scale studies based on mitochondrial markers. PMID:17306026

  7. Comparing two fish sampling standards over time: largely congruent results but with caveats

    USGS Publications Warehouse

    Yule, Daniel L.; Evrard, Lori M.; Cachera, Sébastien; Colon, Michel; Guillard, Jean

    2013-01-01

    1. We sampled Lake Bourget (surface area = 44 km2) using CEN standard gillnet and provisional standard acoustic survey methods over 3 years (2005, 2010 and 2011) as the fish community responded to re-oligotrophication. A total of 16 species were caught in benthic gillnets and three species in pelagic gillnets. 2. Lake Bourget results were consistent with a recent study (Emmrich et al., Freshwater Biology, 57, 2012, 2436) showing strong correspondence between average biomass-per-unit-effort (BPUE) in standard benthic gillnets and average acoustic volume backscattering when smaller lakes (0.25–5.45 km2) were treated as sample units. 3. The BPUE of whitefish (Coregonus lavaretus), perch (Perca fluviatilis) and roach (Rutilus rutilus) measured by benthic gillnets all declined significantly with increasing bathymetric depth; 93% of nets set at depths >50 m caught zero fish. 4. Pelagic gillnetting indicated that small (20 m) increased significantly after 2005. 5. Both surveys showed whitefish biomass increased significantly during the study, but whitefish ?25 cm were poorly represented in benthic gillnet catches. Contrary to the acoustic findings, the BPUE of perch and roach in benthic gillnets did not vary significantly over time. This metric is insensitive to changes in size structure in that a high catch of small fish and a low catch of large fish in different years can provide similar average BPUE estimates. 6. We examined correlations between BPUE in benthic gillnets and acoustic methods at fine spatial scales by averaging acoustic backscattering measurements encompassed by buffers of varying size (250–2000 m) around individual gillnets and by averaging samples collected from lake quadrants. Correlations at fines scales were generally poor, and only in 1 year was the quadrant correlation significant. The lack of correlation can be explained, in part, by the two gears sampling different components of the fish community. Conversely, in pelagic habitat, where the fish community was simpler, we found BPUE in pelagic nets to be strongly correlated with acoustic backscattering. 7. With respect to large lakes like Lake Bourget, we hypothesise that the congruence in average biomass measurements provided by these two survey methods occurs because these different community components are responding similarly to a common driver like lake trophic status (or possibly multiple drivers operating in synergy).

  8. Oil shale processing as a source of aquatic pollution: monitoring of the biologic effects in caged and feral freshwater fish.

    PubMed Central

    Tuvikene, A; Huuskonen, S; Koponen, K; Ritola, O; Mauer, U; Lindström-Seppä, P

    1999-01-01

    The biologic effects of the oil shale industry on caged rainbow trout (Oncorhynchus mykiss) as well as on feral perch (Perca fluviatilis) and roach (Rutilus rutilus) were studied in the River Narva in northeast Estonia. The River Narva passes the oil shale mining and processing area and thus receives elevated amounts of polycyclic aromatic hydrocarbons (PAHs), heavy metals, and sulfates. The effects of the chemical load were monitored by measuring cytochrome P4501A (CYP1A)-dependent monooxygenase (MO) activities [7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase (AHH)] as well as conjugation enzyme activities [glutathione S-transferase (GST) and UDP-glucuronosyltransferase] in the liver of fish. CYP1A induction was further studied by detecting the amount and occurrence of the CYP1A protein. Histopathology of tissues (liver, kidney, spleen, and intestine) and the percentage of micronuclei in fish erythrocytes were also determined. Selected PAHs and heavy metals (Cd, Cu, Hg, and Pb) were measured from fish muscle and liver. In spite of the significant accumulation of PAHs, there was no induction of MO activities in any studied fish species. When compared to reference samples, AHH activities were even decreased in feral fish at some of the exposed sites. Detection of CYP1A protein content and the distribution of the CYP1A enzyme by immunohistochemistry also did not show extensive CYP1A induction. Instead, GST activities were significantly increased at exposed sites. Detection of histopathology did not reveal major changes in the morphology of tissues. The micronucleus test also did not show any evidence of genotoxicity. Thus, from the parameters studied, GST activity was most affected. The lack of catalytic CYP1A induction in spite of the heavy loading of PAHs was not studied but has been attributed to the elevated content of other compounds such as heavy metals, some of which can act as inhibitors for MOs. Another possible explanation of this lack of induction is that through adaptation processes the fish could have lost some of their sensitivity to PAHs. Either complex pollution caused by oil shale processing masked part of the harmful effects measured in this study, or oil shale industry did not have any severe effects on fish in the River Narva. Our study illustrates the difficulties in estimating risk in cases where there are numerous various contaminants affecting the biota. Images Figure 1 Figure 2 PMID:10464075

  9. Oil shale processing as a source of aquatic pollution: monitoring of the biologic effects in caged and feral freshwater fish.

    PubMed

    Tuvikene, A; Huuskonen, S; Koponen, K; Ritola, O; Mauer, U; Lindström-Seppä, P

    1999-09-01

    The biologic effects of the oil shale industry on caged rainbow trout (Oncorhynchus mykiss) as well as on feral perch (Perca fluviatilis) and roach (Rutilus rutilus) were studied in the River Narva in northeast Estonia. The River Narva passes the oil shale mining and processing area and thus receives elevated amounts of polycyclic aromatic hydrocarbons (PAHs), heavy metals, and sulfates. The effects of the chemical load were monitored by measuring cytochrome P4501A (CYP1A)-dependent monooxygenase (MO) activities [7-ethoxyresorufin O-deethylase and aryl hydrocarbon hydroxylase (AHH)] as well as conjugation enzyme activities [glutathione S-transferase (GST) and UDP-glucuronosyltransferase] in the liver of fish. CYP1A induction was further studied by detecting the amount and occurrence of the CYP1A protein. Histopathology of tissues (liver, kidney, spleen, and intestine) and the percentage of micronuclei in fish erythrocytes were also determined. Selected PAHs and heavy metals (Cd, Cu, Hg, and Pb) were measured from fish muscle and liver. In spite of the significant accumulation of PAHs, there was no induction of MO activities in any studied fish species. When compared to reference samples, AHH activities were even decreased in feral fish at some of the exposed sites. Detection of CYP1A protein content and the distribution of the CYP1A enzyme by immunohistochemistry also did not show extensive CYP1A induction. Instead, GST activities were significantly increased at exposed sites. Detection of histopathology did not reveal major changes in the morphology of tissues. The micronucleus test also did not show any evidence of genotoxicity. Thus, from the parameters studied, GST activity was most affected. The lack of catalytic CYP1A induction in spite of the heavy loading of PAHs was not studied but has been attributed to the elevated content of other compounds such as heavy metals, some of which can act as inhibitors for MOs. Another possible explanation of this lack of induction is that through adaptation processes the fish could have lost some of their sensitivity to PAHs. Either complex pollution caused by oil shale processing masked part of the harmful effects measured in this study, or oil shale industry did not have any severe effects on fish in the River Narva. Our study illustrates the difficulties in estimating risk in cases where there are numerous various contaminants affecting the biota. PMID:10464075

  10. Effects of predation pressure and resource use on morphological divergence in omnivorous prey fish

    PubMed Central

    2013-01-01

    Background Body shape is one of the most variable traits of organisms and responds to a broad array of local selective forces. In freshwater fish, divergent body shapes within single species have been repeatedly observed along the littoral-pelagic axes of lakes, where the structural complexity of near shore habitats provides a more diverse set of resources compared to the open-water zones. It remains poorly understood whether similar resource-driven polymorphism occurs among lakes that vary in structural complexity and predation pressure, and whether this variation is heritable. Here, we analyzed body shape in four populations of omnivorous roach (Rutilus rutilus) inhabiting shallow lakes. We tested the relationship between body shape, gradients of resources, predation pressure, and, in a subset of two lakes, diet composition. We used genome scans of 331 polymorphic AFLP markers to test whether there was a heritable component to the observed morphological diversification. Results Body shape differed among lakes and was significantly correlated to differences in predation pressure. Roach from the lake with highest predation pressure were most divergent from the average body shape of all populations, characterized by a more streamlined body and caudally inserted dorsal fins; features that facilitate predator escape. Surprisingly, diet composition was not associated with morphology. AFLP analysis revealed weak genetic differentiation among lakes and no isolation by distance (IBD). Outlier analysis detected three loci under positive selection with differing frequencies in the four populations. General linear models did not support an association of lake-specific genotypes with morphological variation. Conclusion Body shape was divergent among lakes, suggesting that processes previously reported from within single lakes may also be operating at the scale of whole lakes. We found no evidence for body shape being heritable, although sample size was small in these natural populations. Rather than habitat structure and diet, we conclude that predation had a stronger effect on the prevalence of local morphotypes. A variable morphotype facilitating the efficient uptake of a variety of spatially and temporarily scattered resources seems to be favored in these small aquatic systems. PMID:23802571

  11. Contemporary radiation doses to murine rodents inhabiting the most contaminated part of the EURT.

    PubMed

    Malinovsky, G P; Yarmoshenko, I V; Zhukovsky, M V; Starichenko, V I; Chibiryak, M V

    2014-03-01

    The contemporary radiation doses to the organs and tissues of murine rodents inhabiting the most contaminated part of the EURT were estimated. The bones of animals trapped in 2005 at territories with a surface (90)Sr contamination of 24-40 MBq/m(2) were used for dose reconstruction. The concentration of (90)Sr in the animals' skulls was measured using the nondestructive method of bone radiometry. The dose estimation procedure included application of the published values of absorbed fractions of beta-radiation energy for different combinations of source and target organs, accounting for the distribution of radionuclide by organs and tissues. Twelve conversion coefficients were obtained to link the skeleton (90)Sr concentration and doses to eleven organs and the whole body. The whole-body dose rate on the 45th day after the beginning of exposure normalised to whole-body activity is 0.015 (mGy day(-1))/(Bq g(-1)). The estimation yields the following values of doses for Microtus agrestis, Sylvaemus uralensis and Clethrionomys rutilus, respectively: maximum absorbed doses in the skeleton: 267, 121 and 160 mGy; mean whole body internal doses: 37, 14 and 23 mGy; mean internal dose rates on the last day before trapping: 1.2; 0.44 and 0.75 mGy/day. Approaches to the assessment of doses to foetuses and to offspring before weaning were also developed. PMID:24333639

  12. A new intermediate host for Echinococcus multilocularis: the southern red-backed vole (Myodes gapperi) in urban landscape in Calgary, Canada.

    PubMed

    Liccioli, Stefano; Duignan, Pádraig J; Lejeune, Manigandan; Deunk, Joanna; Majid, Sultana; Massolo, Alessandro

    2013-08-01

    Human Alveolar Echinococcosis (HAE) is a potentially fatal parasitic disease caused by Echinococcus multilocularis, a cestode characterized by a sylvatic life-cycle involving several species of rodents and lagomorphs as intermediate hosts and canids as definitive hosts. Despite the wide distribution of the parasite in North America, the number of competent intermediate host species identified to date is still relatively small, and mainly includes the northern vole (Microtus oeconomus), brown lemming (Lemmus sibiricus), northern red-backed vole (Myodes rutilus), deer mouse (Peromyscus maniculatus) and meadow vole (Microtus pennsylvanicus). By monitoring the infections in rodents in the city of Calgary (Alberta, Canada), we have detected a case of severe alveolar echinococcosis in a southern red-backed vole (Myodes gapperi), a species never reported before as an intermediate host for this parasite. Observation of protoscolices in the intra-abdominal multilocular cysts indicates that M. gapperi could act as a competent intermediate host for the transmission of E. multilocularis. Since M. gapperi can be found in close proximity to, and within metropolitan areas, this species could play a role in the establishment and maintenance of the sylvatic life-cycle of E. multilocularis in urban landscapes, where the potential for zoonotic transmission is higher. The new intermediate host reported needs to be taken into account in future surveys and transmission models for this parasite. PMID:23608104

  13. Evaluation of metal pollution in fish and water collected from Gorgan coast of the Caspian Sea, Iran.

    PubMed

    Saeedi Saravi, S S; Karami, B; Karami, S; Shokrzadeh, M

    2012-08-01

    In this study, concentrations of zinc, chromium, cadmium and lead were determined in water and three species of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometery, summer 2009. Mean lead levels in water and fish samples (119.50 ± 22.24 ?g/L and 113.80 ± 33.11 ?g/kg) were significantly higher than that of cadmium and chromium (p < 0.05). Cyprinus carpio had highest metals content than Mugila auratus and Rutilus frisikutum. The evaluated metals values in water collected from Gomishan wetland (Pb, Cd, Cr and Zn values are 145.31 ± 35.32, 120.46 ± 11.44, 96.47 ± 6.05 and 82.02 ± 34.37 ?g/L, respectively) were higher than the other sampling sites. The result is consistent with the findings accessed by evaluation of the metals in fish specimens. The metals concentrations in the fish and water samples were below the recommended limits. But, elevating levels of metals in water and fish made a serious concern about ecosystem and food chain contamination. PMID:22664555

  14. Vacuolating encephalopathy and retinopathy associated with a nodavirus-like agent: a probable cause of mass mortality of wild Golden grey mullet (Liza aurata) and Sharpnose grey mullet (Liza saliens) in Iranian waters of the Caspian Sea.

    PubMed

    Zorriehzahra, Mohammad Jalil; Nazari, Alireza; Ghasemi, Mohaddes; Ghiasi, Maryam; Karsidani, Somayeh Haghighi; Bovo, Giuseppe; Daud, Hassan Hj Mohd

    2014-12-01

    Mullets are dominant fishes in the catch composition in the southern coasts of the Caspian Sea and after (Rutilus frisii kutum Kamensky, 1901) have a worthy role in production of marine proteins and incomings of north provinces of Iran. Mullets stocks decreased dramatically in recent decades in the Caspian Sea and catch amount reached from 6446 MT on 2002 to 2151 MT in 2012. Mysterious mortalities occurred in wild mullet (Liza auratu) and (Liza saliens) in Iranian waters of Caspian Sea in recent years. Regarding to investigation of causative agent of mentioned outbreak about 322 suspected samples were collected from coastal capture sites of Iranian north provinces in 2008 till 2011. Moribund fish revealed skin darkening, erratic swimming, belly-up at rest and high distension of swim bladder. Target tissues such as brain and eye were removed and then fixed for histopathology and TEM assay. Widespread and massive vacuolation were observed in brain, spinal cord, retina and optical nerve and intracytoplasmic vacuoles and virus particles in retina. So concerning to clinical signs, histopathological and TEM findings, it could be concluded that nodavirus-like agent could be probable cause of mass mortality of wild mullet in Iranian waters of the Caspian Sea. PMID:25674618

  15. Vector and host relationships of California serogroup viruses in western Siberia.

    PubMed

    Mitchell, C J; Lvov, S D; Savage, H M; Calisher, C H; Smith, G C; Lvov, D K; Gubler, D J

    1993-07-01

    During 1990 and 1991, adult mosquitoes were collected along the Ob River and its tributaries in western Siberia from approximately 51 degrees 18'N to 66 degrees 4'N. Fifteen virus strains were isolated from 74,196 mosquitoes tested in 1,874 pools. These included Tahyna virus from Aedes cataphylla-punctor subgroup (one) and Ae. excrucians (one), and Inkoo (INK) virus from Ae. communis (one), Ae. communis subgroup (one), Ae. hexodontus (two), Ae. punctor subgroup (two), Ae. punctor complex (one), and unidentified Aedes species (three). In addition, a single Ae. euedes yielded a strain of snowshoe hare (SSH) virus and a strain of Getah, an alphavirus. A Bunyamwera serogroup virus was isolated from Ae. excrucians. With the exception of the two isolates from a single mosquito, minimum infection rates among mosquito taxa ranged from 0.4 to 16.7 per 1,000. The INK virus isolates were widely distributed geographically; however, seven of the 10 isolates were from two sites north of the Arctic Circle. During 1991, sera from two mouse species, five vole species, and four shrew species were collected along the upper Ob River for serologic tests. The prevalence of neutralizing antibody to SSH virus in these sera was 80%. Prevalence rates in the four most abundant species were Apodemus agrarius, 73%; Clethrionomys rutilus, 71%; Microtus arvalis, 80%; and Sorex araneus, 91%. This is the first attempt to clarify the vector and vertebrate host relationships of California serogroup viruses in western Siberia. PMID:8352392

  16. Molecular cytogenetic analysis of the Appenine endemic cyprinid fish Squalius lucumonis and three other Italian leuciscines using chromosome banding and FISH with rDNA probes.

    PubMed

    Rossi, Anna Rita; Milana, Valentina; Hett, Anne Kathrin; Tancioni, Lorenzo

    2012-12-01

    Karyotype and other chromosomal characteristics of the Appenine endemic cyprinid fish, Toscana stream chub Squalius lucumonis, were analysed using conventional banding and FISH with 45S and 5S rDNA probes. The diploid chromosome number (2n = 50) and karyotype characteristics including pericentromeric heterochromatic blocks and GC-rich CMA(3)-positive sites corresponding to both positive Ag-NORs and 45S rDNA loci on the short arms of a single medium-sized submetacentric chromosome pair were consistent with those found in most European leuciscine cyprinids. On other hand, 5S rDNA FISH in the Toscana stream chub and three other Italian leuciscines, S. squalus, Rutilus rubilio and Telestes muticellus, revealed a species-specific hybridization pattern, i.e. signals on four (S. lucumonis), three (S. squalus and R. rubilio) and two (T. muticellus) chromosome pairs. Whereas all the species shared the 5S rDNA loci on the largest subtelocentric chromosome pair, a "leuciscine" cytotaxonomic marker, S. lucumonis showed both classes of rDNA loci tandem aligned on the short arms of chromosome pair No. 12. The present findings suggest that the observed high variability of 5S rDNA loci provides a powerful tool for investigation of karyotype differentiation in karyologically conservative leuciscine fishes. PMID:23238894

  17. Testing Species Delimitations in Four Italian Sympatric Leuciscine Fishes in the Tiber River: A Combined Morphological and Molecular Approach

    PubMed Central

    Tancioni, Lorenzo; Russo, Tommaso; Cataudella, Stefano; Milana, Valentina; Hett, Anne Kathrin; Corsi, Elisa; Rossi, Anna Rita

    2013-01-01

    Leuciscine fishes represent an important component of freshwater ichthyofauna endemic to northern Mediterranean areas. This lineage shows high intra-specific morphological variability and exhibits high levels of hybridization, two characteristics that contribute to systematic uncertainties, misclassification of taxa and, potentially, the mismanagement of biodiversity. This study focused on brook chub, Squalius lucumonis, an endemic taxon of Central Italy. The taxonomic status of this species has long been questioned, and a hybrid origin from sympatric leusciscines (S. squalus x Rutilus rubilio, or S. squalus x Telestes muticellus) has been hypothesised. A phenotypic (evaluating shape and meristic counts) and genetic (using mitochondrial and nuclear markers) investigation of these four taxa was conducted to test species delimitation in sympatric areas and to evaluate the taxonomic status of S. lucumonis. One hundred and forty-five individuals of all four taxa were collected within streams of the lowest portion of the Tiber River basin and analysed; this region encompasses a large portion of the S. lucumonis distribution. The different morphological and genetic approaches were individually examined, compared, and then combined in a quantitative model to both investigate the limits of each approach and to identify cases of misclassification. The results obtained confirm the cladogenetic non-hybrid origin of S. lucumonis, highlight the need for immediate conservation actions and emphasise the value of an integrated approach in the study of leuciscines evolution. PMID:23565240

  18. Occurrence of some organic UV filters in wastewater, in surface waters, and in fish from Swiss Lakes.

    PubMed

    Balmer, Marianne E; Buser, Hans-Rudolf; Müller, Markus D; Poiger, Thomas

    2005-02-15

    Organic UV filters are used in personal care products such as sunscreen products, and in cosmetics, beauty creams, skin lotions, lipsticks, hair sprays, hair dyes, shampoos, and so forth. The compounds enter the aquatic environmentfrom showering, wash-off, washing (laundering), and so forth via wastewater treatment plants (WWTPs) ("indirect inputs") and from recreational activities such as swimming and bathing in lakes and rivers ("direct inputs"). In this study, we investigated the occurrence of four important organic UV filter compounds (benzophenone-3, BP-3; 4-methylbenzylidene camphor, 4-MBC; ethylhexyl methoxy cinnamate, EHMC; octocrylene, OC) in wastewater, and in water and fish from various Swiss lakes, using gas chromatographic/mass spectrometric analyses. All four UV filters were present in untreated wastewater (WWTP influent) with a maximum concentration of 19 microg L(-1) for EHMC. The data indicate a seasonal variation with influent loads higher in the warmer season (June 2002) than in the colder one (April 2002). The influent loads were in the order EHMC > 4-MBC approximately BP-3 > OC. The concentrations in treated wastewater (WWTP effluent) were considerably lower, indicating substantial elimination in the plants. 4-MBC was usually the most prevalent compound (maximum concentration, 2.7 microg L(-1)), followed by BP-3, EHMC, and OC. UV filters were also detected in Swiss midland lakes and a river (Limmat) receiving inputs from WWTPs and recreational activities. However, all concentrations were low (<2-35 ng L(-1)); no UV filters (<2 ng L(-1)) were detected in a remote mountain lake. Data from passive sampling using semipermeable membrane devices (SPMDs) supported the presence of these UV filters in the lakes and the river and suggested some potential for accumulation of these compounds in biota. SPMD-derived water concentrations increased in the order Greifensee < Zürichsee < Hüttnersee. This order is reversed from that observed for methyl triclosan, used as a chemical marker for WWTP-derived lipophilic contaminants in the lakes. This indicated inputs of UV filters from sources other than WWTPs to the lakes during summer,for example,inputs from recreational activities. Fish (white fish, Coregonus sp.; roach, Rutilus rutilus; perch, Perca fluviatilis) from these lakes contained low but detectable concentrations of UV filters, in particular, 4-MBC (up to 166 ng g(-1) on a lipid basis). 4-MBC concentrations relative to methyl triclosan were lower in fish than in SPMDs exposed in the same lakes, suggesting that 4-MBC is less bioaccumulated than expected or metabolized in fish. The lipid-based bioconcentration factor (BCF(L)) estimated from the fish (roach) data and SPMD-derived water concentrations was about 1-2.3 x 10(4) and thus approximately 1 order of magnitude lower than expected from its Kow value. PMID:15773466

  19. Naturally Occurring Orthopoxviruses: Potential for Recombination with Vaccine Vectors

    PubMed Central

    Sandvik, Tore; Tryland, Morten; Hansen, Hilde; Mehl, Reidar; Moens, Ugo; Olsvik, Řrjan; Traavik, Terje

    1998-01-01

    Orthopoxviruses are being increasingly used as live recombinant vectors for vaccination against numerous infectious diseases in humans, domestic animals, and wildlife. For risk assessments and surveillance, information about the occurrence, distribution and ecology of orthopoxviruses in western Europe is important but has mainly been based on serological investigations. We have examined kidneys, lungs, spleens, and livers of Norwegian small rodents and common shrews (Sorex araneus) for the presence of orthopoxvirus DNA sequences by PCR with primers complementary to the viral thymidine kinase (TK) gene. PCR amplicons were verified as orthopoxvirus specific by hybridization with a vaccinia virus TK-specific probe. A total of 347 animals (1,388 organs) from eight locations in different parts of Norway, collected at different times of the year during 1993 to 1995, were examined. Fifty-two animals (15%) from five locations, up to 1,600 km apart, carried orthopoxvirus DNA in one or more of their organs, most frequently in the lungs. These included 9 of 68 (13%) bank voles (Clethrionomys glareolus), 4 of 13 (31%) gray-sided voles (Clethrionomys rufocanus), 3 of 11 (27%) northern red-backed voles (Clethrionomys rutilus), 16 of 76 (21%) wood mice (Apodemus sylvaticus), and 20 of 157 (13%) common shrews. The previous isolation of cowpox virus from two clinical cases of infection (human and feline) at two of the locations investigated suggests that the viruses detected are cowpox and that some of the virus-carrying small mammalian species should be included among the cowpox virus natural reservoir hosts in Scandinavia and western Europe. PMID:9705389

  20. [Developmental instability of the organism as a result of pessimization of environment under anthropogenic transformation of natural landscapes].

    PubMed

    Shadrina, E G; Vol'pert, Ia L

    2014-01-01

    The value of fluctuating asymmetry is considered to be an indicator of the developmental instability of the organism. The consequences of activities of the mining industry plants, which are characterized by alienation and transformation of large areas of natural landscapes, are analyzed as an anthropogenic factor. The objects of study were small mammals (northern red-backed (Clethrionomys rutilus) and gray red-backed (Clethrionomys rufocanus) voles, tundra vole (Microtus oeconomus), Laxmann's (Sorex caecutiens) and tundra (S. tundrensis) shrews) and trees (Japanese white birch (Betula platyphylla), Betula divaricate, Betula exilis, Duschekiafruticosa, and common osier (Salix viminalis)). In total, 3500 skulls and approximately 30000 leaves collected in the taiga zone of Yakutia were studied. The index offluctuating asymmetry, as well as population parameters and composition of small mammal communities, were analyzed. The data on the value of the fluctuating asymmetry in the studied species in natural habitats are given. It is shown that, in natural conditions, this parameter can rise with deterioration in living conditions, particularly at the ecological periphery of the range. Anthropogenic transformation of natural landscapes creates an "anthropogenic periphery" and causes changes similar to the adaptive responses at the northern limit of the distribution of species. It was found that, through pollution and disruption of ecosystems, the mining industry affects all levels of organization of the living matter, but the population and cenotic parameters give an unambiguous response only at macroanthropogenic transformations. Increase in the level of fluctuating asymmetry is the most sensitive indicator of anthropogenic impact and it should also be taken into account that disruptions in the developmental stability of an organism reflect the destructive processes occurring in the population and community. PMID:25720274

  1. Attracted to the enemy: Aedes aegypti prefers oviposition sites with predator-killed conspecifics.

    PubMed

    Albeny-Simőes, Daniel; Murrell, Ebony G; Elliot, Simon L; Andrade, Mateus R; Lima, Eraldo; Juliano, Steven A; Vilela, Evaldo F

    2014-06-01

    Oviposition habitat choices of species with aquatic larvae are expected to be influenced by both offspring risk of mortality due to predation, and offspring growth potential. Aquatic predators may indirectly influence growth potential for prey by reducing prey density and, for filter-feeding prey, by increasing bacterial food for prey via added organic matter (feces, partially eaten victims), creating the potential for interactive effects on oviposition choices. We tested the hypothesis that the mosquito Aedes aegypti preferentially oviposits in habitats with predatory Toxorhynchites larvae because of indirect effects of predation on chemical cues indicating bacterial abundance. We predicted that A. aegypti would avoid oviposition in sites with Toxorhynchites, but prefer to oviposit where bacterial food for larvae is abundant, and that predation by Toxorhynchites would increase bacterial abundances. Gravid A. aegypti were offered paired oviposition sites representing choices among: predator presence; the act of predation; conspecific density; dead conspecific larvae; and bacterial activity. A. aegypti preferentially oviposited in sites with Toxorhynchites theobaldi predation, and with killed conspecific larvae, but failed to detect preferences for other treatments. The antibiotic tetracycline eliminated the strongest oviposition preference. Both predation by Toxorhynchites and killed larvae increased bacterial abundances, suggesting that oviposition attraction is cued by bacteria. Our results show the potential for indirect effects, like trophic cascades, to influence oviposition choices and community composition in aquatic systems. Our results suggest that predators like Toxorhynchites may be doubly beneficial as biocontrol agents because of the attraction of ovipositing mosquitoes to bacterial by-products of Toxorhynchites feeding. PMID:24590205

  2. Tracing the colonization history of the Indian Ocean scops-owls (Strigiformes: Otus) with further insight into the spatio-temporal origin of the Malagasy avifauna

    PubMed Central

    2008-01-01

    Background The island of Madagascar and surrounding volcanic and coralline islands are considered to form a biodiversity hotspot with large numbers of unique taxa. The origin of this endemic fauna can be explained by two different factors: vicariance or over-water-dispersal. Deciphering which factor explains the current distributional pattern of a given taxonomic group requires robust phylogenies as well as estimates of divergence times. The lineage of Indian Ocean scops-owls (Otus: Strigidae) includes six or seven species that are endemic to Madagascar and portions of the Comoros and Seychelles archipelagos; little is known about the species limits, biogeographic affinities and relationships to each other. In the present study, using DNA sequence data gathered from six loci, we examine the biogeographic history of the Indian Ocean scops-owls. We also compare the pattern and timing of colonization of the Indian Ocean islands by scops-owls with divergence times already proposed for other bird taxa. Results Our analyses revealed that Indian Ocean islands scops-owls do not form a monophyletic assemblage: the Seychelles Otus insularis is genetically closer to the South-East Asian endemic O. sunia than to species from the Comoros and Madagascar. The Pemba Scops-owls O. pembaensis, often considered closely related to, if not conspecific with O. rutilus of Madagascar, is instead closely related to the African mainland O. senegalensis. Relationships among the Indian Ocean taxa from the Comoros and Madagascar are unresolved, despite the analysis of over 4000 bp, suggesting a diversification burst after the initial colonization event. We also highlight one case of putative back-colonization to the Asian mainland from an island ancestor (O. sunia). Our divergence date estimates, using a Bayesian relaxed clock method, suggest that all these events occurred during the last 3.6 myr; albeit colonization of the Indian Ocean islands were not synchronous, O. pembaensis diverged from O. senegalensis about 1.7 mya while species from Madagascar and the Comoro diverged from their continental sister-group about 3.6 mya. We highlight that our estimates coincide with estimates of diversification from other bird lineages. Conclusion Our analyses revealed the occurrence of multiple synchronous colonization events of the Indian Ocean islands by scops-owls, at a time when faunistic exchanges involving Madagascar was common as a result of lowered sea-level that would have allowed the formation of stepping-stone islands. Patterns of diversification that emerged from the scops-owls data are: 1) a star-like pattern concerning the order of colonization of the Indian Ocean islands and 2) the high genetic distinctiveness among all Indian Ocean taxa, reinforcing their recognition as distinct species. PMID:18611281

  3. Content of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in fish from Latvian lakes.

    PubMed

    Zacs, D; Bartkevics, V; Viksna, A

    2013-04-01

    Seventeen polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) of the highest priority as well as twelve dioxin-like polychlorinated biphenyls (dl-PCBs) were analyzed in the muscle tissues of the following freshwater fish species sampled from eleven Latvian freshwater lakes: perch (Perca flavescens), carp (Cyprinus carpio), eel (Anguilla rostrata), bream (Abramis brama), chub (Leuciscus cephalus), pike (Esox lucius), sheatfish (Silurus glanis) and roach (Rutilus). To analyze the selected persistent organic pollutants in fish matrices, an optimization of EPA-1613 and EPA-1668A clean-up procedures was carried out, followed by validation of the analytical procedure according to Commission Regulation (EC) No 1883/2006. The adopted analytical procedure was in compliance with requirements of the more recent Commission Regulation (EU) No 252/2012. Modifications of carbon column chromatography clean-up and separation steps were used for treatment of the fish samples. Other clean-up procedure stages were performed according to the methods EPA-1613 and EPA-1668A and involved gel permeation chromatography (GPC), as well as manual acidic silica and Florisil column chromatography for purification and fractionation of the samples. An isotope dilution method was used for the qualitative and quantitative determination of individual congeners. Analytes of interest were separated and detected using gas chromatography - high resolution mass spectrometry. The concentration of PCDD/PCDFs and dl-PCBs in freshwater fish and eel samples ranged from 0.05 to 8.0 pg WHO(1998)-PCDD/PCDF-PCB-TEQ g(-1) fresh weight. These levels are below the EU maximum permissible limits although calculation of the content of these compounds relative to the weight of fat shows contamination levels similar to those found in Baltic herring and sprats, that are known to be highly contaminated. A difference in congener pattern between the Baltic Sea fish and freshwater fish was detected with lower contribution of 2,3,4,7,8-PeCDF to the contamination of inland water fish. PMID:23336927

  4. Medically important mosquitoes in the rubber plantation belt of central Kerala, India.

    PubMed

    Jomon K V; Valamparampil T T

    2014-07-01

    Entomological surveys were carried out in the rubber plantation belt of Kerala to record mosquito fauna. Samples were collected from 23 randomly selected localities using standard methods for a period of three years, from Feb- ruary 2008 to January 2011. Thirty-two species belonging to nine genera: Aedes, Anopheles, Armigeres, Coquillettidia, Culex, Heizmannia, Mansonia, Toxorhynchites, and Uranotaenia were recorded. Many of the recorded species were medically im- portant as potential vectors of dengue fever, chikungunya, Japanese encephalitis, malaria and filariasis. PMID:25507596

  5. Medically important mosquitoes in the rubber plantation belt of central Kerala, India.

    PubMed

    Jomon K V; Valamparampil T T

    2014-07-01

    Entomological surveys were carried out in the rubber plantation belt of Kerala to record mosquito fauna. Samples were collected from 23 randomly selected localities using standard methods for a period of three years, from Feb- ruary 2008 to January 2011. Thirty-two species belonging to nine genera: Aedes, Anopheles, Armigeres, Coquillettidia, Culex, Heizmannia, Mansonia, Toxorhynchites, and Uranotaenia were recorded. Many of the recorded species were medically im- portant as potential vectors of dengue fever, chikungunya, Japanese encephalitis, malaria and filariasis. PMID:25427346

  6. Epidemiology of tree-hole breeding mosquitoes in the tropical rainforest of Imo State, south-east Nigeria.

    PubMed

    Anosike, Jude C; Nwoke, Bertram E B; Okere, Anthony N; Oku, Ene E; Asor, Joe E; Emmy-Egbe, Ifeyinwa O; Adimike, Desmond A

    2007-01-01

    The study of tree-hole breeding mosquitoes was carried out in the tropical rainforest of Imo State Nigeria (two rural areas and two forest reserves in some parts of Orlu Senatorial Zone) between May-October 2002. Using standard entomological procedures, two macrohabitats (natural tree-holes and bamboo traps) and two microhabitats (leaf axils of cocoyams/pineapples and leaf axils of plantain/banana) were sampled for various mosquito species. Mosquitoes were recovered from all the various biotypes sampled. Types of mosquitoes species encountered, their relative abundance, as well as genera varied significantly during the study (p<0.05). Four genera of mosquitoes: Aedes, Culex, Anopheles and Toxorhynchites were recovered while 16 species of mosquitoes encountered include: Aedes aegypti, Ae. africanus, Ae. simpsoni, Ae. albopictus, Ae. stokesi, Ae. taylori, Ae. apicoargenteus, Culex quinquefasciatus, Cx. nebulosus, Cx. trigripes, Cx. decens, Anopheles gambiae, An. funiestus, An. coustani and Toxorhynchites viridibasis. Most of the mosquitoes showed oviposition preferences for one or more habitats. The presence of Ae. africanus, Ae. simpsoni and Ae. aegypti indicate that the study areas were at risk of yellow fever epidemic. The presence of Anopheles and Culex species ensured endemicity of malaria and filariasis, while the recovery of Ae. albopictus in this region suggests a possible outbreak of dengue fever in future if not properly controlled. PMID:17655174

  7. Mosquitoes of the mangrove forests of India: part 5--Chorao, Goa, and Vikhroli, Maharashtra.

    PubMed

    Rajavel, A R; Natarajan, R; Vaidyanathan, K; Soniya, V P

    2007-06-01

    Mosquitoes of 14 species belonging to 9 subgenera and 9 genera were recorded in Chorao mangroves of Goa, and 12 species belonging to 9 subgenera and 7 genera in the mangroves of Vikhroli, Maharashtra, in India. Genera recorded were Aedes, Anopheles, Armigeres, Culex, Mansonia, Ochlerotatus, Orthopodomyia, Toxorhynchites, Uranotaenia, and Verrallina. Species common to both the mangroves were Ae. albopictus, Ae. novalbopictus, An. subpictus, Cx. sitiens, Oc. wardi, Ur. atra, and Ve. lugubris. Tree holes, crab holes, and swamp pools were the common larval habitats in Chorao, but tree holes were absent in Vikhroli. Adults of Ae. albopictus, Ae. novalbopictus, Ar. subalbatus, Cx. gelidus Cx. sitiens, Ma. indiana, Ur. atra, and Ve. lugubris were found landing on humans. Aedes novalbopictus, Oc. wardi, and Or. anopheloides are new records for the state of Goa. PMID:17847838

  8. Modelling the Active Hearing Process in Mosquitoes

    NASA Astrophysics Data System (ADS)

    Avitabile, Daniele; Homer, Martin; Jackson, Joe; Robert, Daniel; Champneys, Alan

    2011-11-01

    A simple microscopic mechanistic model is described of the active amplification within the Johnston's organ of the mosquito species Toxorhynchites brevipalpis. The model is based on the description of the antenna as a forced-damped oscillator coupled to a set of active threads (ensembles of scolopidia) that provide an impulsive force when they twitch. This twitching is in turn controlled by channels that are opened and closed if the antennal oscillation reaches a critical amplitude. The model matches both qualitatively and quantitatively with recent experiments. New results are presented using mathematical homogenization techniques to derive a mesoscopic model as a simple oscillator with nonlinear force and damping characteristics. It is shown how the results from this new model closely resemble those from the microscopic model as the number of threads approach physiologically correct values.

  9. [Dengue outbreak by virus type 4 in French Polynesia. II. Preliminary biological observations on epidemiology and physiopathology of the disease (author's transl)].

    PubMed

    Parc, F; Tetaria, C; Pichon, G

    1981-01-01

    Authors report some accurate epidemiologic and physiopathologic data about dengue 4. Thanks to virus intrathoracic inoculation in Toxorhynchites amboinensis (Doleshall, 1857), 202 viral strains have been isolated from 633 sera samples. The incidence of the disease has decreased very early after immunization of the whole population and resulted in an eradication of dengue type 1 virus which was endemic in French Polynesia since 1976. Only one type of dengue virus seems to be tolerated in French Polynesian ecosystem in the same time. There is no crossing protection with dengue 1. Clinically, the picture has been the same in both new and previously infected by dengue 1 patients. Duration of viremia during the secondary dengue fever is not shorter than in the primary one. The hemagglutination inhibiting antibodies do not protect patients, but do not result in immune-complexes pathology. PMID:7278575

  10. Mathematical modelling of the active hearing process in mosquitoes

    PubMed Central

    Avitabile, D.; Homer, M.; Champneys, A. R.; Jackson, J. C.; Robert, D.

    2010-01-01

    Insects have evolved diverse and delicate morphological structures in order to capture the inherently low energy of a propagating sound wave. In mosquitoes, the capture of acoustic energy and its transduction into neuronal signals are assisted by the active mechanical participation of the scolopidia. We propose a simple microscopic mechanistic model of the active amplification in the mosquito species Toxorhynchites brevipalpis. The model is based on the description of the antenna as a forced-damped oscillator coupled to a set of active threads (ensembles of scolopidia) that provide an impulsive force when they twitch. This twitching is in turn controlled by channels that are opened and closed if the antennal oscillation reaches a critical amplitude. The model matches both qualitatively and quantitatively with recent experiments: spontaneous oscillations, nonlinear amplification, hysteresis, 2 : 1 resonances, frequency response and gain loss owing to hypoxia. The numerical simulations presented here also generate new hypotheses. In particular, the model seems to indicate that scolopidia located towards the tip of Johnston's organ are responsible for the entrainment of the other scolopidia and that they give the largest contribution to the mechanical amplification. PMID:19447819

  11. Permethrin resistance in Aedes albopictus (Diptera: Culicidae) and associated fitness costs.

    PubMed

    Chan, Hiang Hao; Zairi, Jaal

    2013-03-01

    Insecticide resistance has become a serious issue in vector management programs. Information on insecticidal resistance and its associated mechanisms is important for successful insecticide resistance management. The selection of a colony of permethrin-resistant Aedes albopictus (Skuse) (Diptera: Culicidae), originating from Penang Island, Malaysia, yielded high larval-specific resistance to permethrin and cross-resistance to deltamethrin. Synergism assays showed that the major mechanism underlying this resistance involves cytochrome P450 monooxygenase. The resistance is autosomal, polygenically inherited and incompletely dominant (D = 0.26). Resistant larvae were reared under different conditions to assess the fitness costs. Under high larval density, larval development time of the resistant SGI strain was significantly longer than the susceptible VCRU strain. In both high- and low-density conditions SGI showed a lower rate of emergence and survival compared with the VCRU strain. Resistant larvae were more susceptible to predation by Toxorhynchites splendens (Wiedemann) (Diptera: Culicidae) larvae. The body size of SGI females reared under high-density conditions was larger compared with females of the susceptible strain. SGI females survived longer when starved than did VCRU females. The energy reserve upon eclosion was positively correlated with the size of the adults. PMID:23540125

  12. Mosquito larvicidal and antimicrobial activity of synthesized nano-crystalline silver particles using leaves and green berry extract of Solanum nigrum L. (Solanaceae: Solanales).

    PubMed

    Rawani, Anjali; Ghosh, Anupam; Chandra, Goutam

    2013-12-01

    Silver nanoparticles (AgNPs) that are synthesized by using aqueous extracts of Solanum nigrum L., is a simple, non-toxic and ecofriendly green material. The present study is based on assessments of the larvicidal and antimicrobial activities of the synthesized AgNPs from fresh leaves, dry leaves and green berries of S. nigrum against larvae of Culex quinquefasciatus and Anopheles stephensi and four human pathogenic and five fish pathogenic bacteria respectively. The synthesized nanoparticles are characterized with UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM) analysis. The nanoparticles are spherical to polyhedral in shape with size of 50-100nm (average size of 56.6nm). In larvicidal bioassay with synthesized AgNPs, highest mortality are observed at 10ppm against An. stephensi with LC50 values of 1.33, 1.59, 1.56ppm and LC90 values of 3.97, 7.31, 4.76ppm for dry leaves, fresh leaves and berries respectively. Antibacterial activity test reveals better results against fish pathogenic bacteria than human pathogenic bacteria. Non target organism like Toxorhynchites larvae (mosquito predator), Diplonychus annulatum (predatory water-bug) and Chironomus circumdatus larvae (chironomid) are also exposed to respective lethal concentrations (to mosquito larvae) of dry nanoparticles and no abnormality in the non target organisms are recorded. These results suggest that the synthesized AgNPs of S. nigrum have the potential to be used as an ideal eco-friendly compound for the control of the mosquito larvae and harmful bacteria. PMID:24055718

  13. Spinosad: a biorational mosquito larvicide for use in car tires in southern Mexico

    PubMed Central

    2012-01-01

    Background Car tires are important habitats for mosquito development because of the high density populations they can harbor and their presence in urban settings. Water in experimental tires was treated with one of three insecticides or an untreated control. Aquatic invertebrates were sampled at weekly intervals. Eggs, larval and pupal samples were laboratory-reared to estimate seasonal fluctuations in Aedes aegypti and Ae. albopictus abundance. Results Spinosad treatments at 1 or 5?ppm (mg a.i./liter) provided 6–8?weeks of effective control of Ae. aegypti, Ae. albopictus, Culex quinquefasiatus and Cx. coronator larvae, both in the dry season and the rainy season when mosquito populations increased markedly in southern Mexico. Spinosad continued to provide partial control of larvae for several weeks after initial recolonization of treated tires. The larvicidal performance of VectoBac 12AS (Bacillus thuringiensis var. israelensis) was relatively poor with one week of complete control of Aedes spp. larvae and no discernible control of Culex spp., whereas the duration of larvicidal activity of 1% temephos mineral-based granules was intermediate between those of VectoBac and spinosad treatments. Populations of chironomids, ostracods and Toxorhynchites theobaldi were generally reduced in spinosad and temephos treatments, but were similar in control and VectoBac treatments. Conclusion The present study is the first to report spinosad as an effective larvicide against Cx. coronator, which is currently invading the southern United States. These results substantiate the use of spinosad as a highly effective mosquito larvicide, even in habitats such as unused car tires that can represent prolific sources of adult mosquitoes. PMID:22608138