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Sample records for fish anguilla anguilla

  1. Fecundity of migrating European eel (Anguilla anguilla from Polish waters

    Directory of Open Access Journals (Sweden)

    Marta Dębowska

    2015-09-01

    Full Text Available This study demonstrated that individual fecundity of 34 migrating European female eels Anguilla anguilla increases linearly with body weight (BW and total length (TL. The total individual fecundity of fish from 560 to 1960 g BW was between 981 x 103 and 6320 x 103 eggs, respectively. The mean relative individual fecundity equalled 2415 x 103 (± 524 x 103 per kg BW. The values of this parameter ranged from 1753 x 103 to 3224.5 x 103 kg–1. Based on the results, it might be suggested that A. anguilla has lower total individual fecundity than New Zealand longfin eel (Anguilla dieffenbachii, American eel (Anguilla rostrata and Japanese eel (Anguilla japonica although it has one of the highest fecundity values per kg BW. Total fecundity was strongly depended from fat level in muscle (R2 = 0.9523 and ovary (R2 = 0.9531 as well as level of DHA content in ovary (R2 = 0.8967 and muscle (R2 = 0.6274 (N=10. There were no important relationship between total fecundity and protein level as well as in muscle and ovary

  2. Anguillicola crassus (Nematoda, Dracunculoidea) infections of European eel (Anguilla anguilla) in the Netherlands: epidemiology, pathogenesis and pathobiology.

    NARCIS (Netherlands)

    Haenen, O.L.M.

    1995-01-01

    In the 1980s an eel parasitic nematode, Anguillicola crassus (Nematoda, Dracunculoidea), which infects the swimbladder of European eels ( Anguilla anguilla ) and other freshwater fish species, was introduced into The Netherlands. This thesis describes the epidemiology, pathogenesis, and pathobiology

  3. Effect of the slaughter method on the quality of raw and smoked eels (Anguilla anguilla L.)

    NARCIS (Netherlands)

    Morzel, M.; Vis, van de J.W.

    2003-01-01

    Eels (Anguilla anguilla L.) were slaughtered using two procedures. The commercial method consisted of desliming the fish in dry salt followed by evisceration. The alternative method consisted of stunning and killing in water with a combination of electricity and oxygen removal. Eels slaughtered as

  4. Food, feeding and growth of the eel (Anguilla anguilla L.) in a Dutch eutrophic lake.

    NARCIS (Netherlands)

    Nie, de H.W.

    1988-01-01

    This thesis describes the food, foraging and growth of the eel (Anguilla anguilla). Attention is paid to the abundance and distribution of the food organisms and the feeding and growth of other fish species. The investigations were carried out in the Tjeukemeer (21 km2) in the northern part of the N

  5. Recovery from transportation by road of farmed European eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Boerrigter, J.G.J.; Manuel, R.; Bos, van den R.; Roques, J.A.C.; Spanings, T.; Flik, G.; Vis, van de J.W.

    2015-01-01

    The objective of this study was to assess the effects of transportation of marketable eel (0.15 kg) in the Netherlands with respect to welfare. Eels (Anguilla anguilla) were obtained from a commercial farm and acclimatized for 7 weeks at the laboratory. Fish were transported according to regular com

  6. Effect of the slaughter method on the quality of raw and smoked eels (Anguilla anguilla L.)

    NARCIS (Netherlands)

    Morzel, M.; Vis, van de J.W.

    2003-01-01

    Eels (Anguilla anguilla L.) were slaughtered using two procedures. The commercial method consisted of desliming the fish in dry salt followed by evisceration. The alternative method consisted of stunning and killing in water with a combination of electricity and oxygen removal. Eels slaughtered as c

  7. Morphological, anatomical and histological studies on the olfactory organs and eyes of teleost fish: Anguilla anguilla in relation to its feeding habits

    Directory of Open Access Journals (Sweden)

    K.I. Atta

    2013-05-01

    The average olfactory surface area is about 590.9% of the retinal area. Thus A. anguilla is a macrosmatic species “nose-fish” in which olfaction plays an important role in its feeding habit. It is noticed that, the photoreceptor cell layer in A. anguilla (bottom feeder is made up only of rod cells.

  8. Piscivory and trophic position of Anguilla anguilla in two lakes: importance of macrozoobenthos density

    DEFF Research Database (Denmark)

    Dorner, H.; Skov, Christian; Berg, Søren

    2009-01-01

    The feeding habits of the European eel Anguilla anguilla (> 300 mm total length, L-T) were compared in two lakes of different environmental state: Lake Gro ss er Vatersee (LGV), Germany (clear water, mesotrophic and submerged macrophytes), and Lake Vallum (LV), Denmark (turbid, eutrophic and no s......The feeding habits of the European eel Anguilla anguilla (> 300 mm total length, L-T) were compared in two lakes of different environmental state: Lake Gro ss er Vatersee (LGV), Germany (clear water, mesotrophic and submerged macrophytes), and Lake Vallum (LV), Denmark (turbid, eutrophic...... and no submerged macrophytes). The density of macrozoobenthos was higher in LV (3500 individuals m(-2)) than in LGV (1500 individuals m(-2)). The abundance of small prey fishes (40-99 mm L-T) was highest in LV. In LV, A. anguilla fed on macrozoobenthos, in particular, chironomid larvae. In LGV, A. anguilla used...... on these results, it is concluded that piscivory among A. anguilla was generally controlled by the density of macrozoobenthos. Stable isotope analysis further indicated that A. anguilla may act as integrators between benthic and pelagic food webs when density of insect larvae is low....

  9. Antibacterial Activity of Eel (Anguilla spp.) Mucus against Salmonella typhi

    OpenAIRE

    Tomy Nurtamin; Resty Yulianita Nurman; Indria Hafizah

    2016-01-01

    BACKGROUND: Typhoid fever has become one global health problem. Typhoid fever is caused by a Gram-negative bacterium, Salmonella typhi. Eel (Anguilla spp.) is a fish which lives in the sea or in freshwater. Several previous studies have found that Anguilla spp. mucus has the ability as antibacterial against Gram-positive and negative. Although the antibacterial activity of Anguilla spp. against various pathogens had been reported, very little is known about its activity against Salmonella typ...

  10. Heading south or north: novel insights on European silver eel Anguilla anguilla migration in the North Sea

    NARCIS (Netherlands)

    Huisman, Jeroen; Verhelst, Pieterjan; Verhelst, Pieterjan; Deneudt, K.; Goethals, Peter; Moens, Tom; Nagelkerke, Leopold A.J.; Nolting, Carsten; Reubens, Jan; Schollema, Peter Paul; Winter, Hendrik V.; Mouton, Ans

    2016-01-01

    The European eel Anguilla anguilla L. is a critically endangered fish species that migrates from coastal and freshwater habitats to the Sargasso Sea to spawn. However, the exact migration routes and destination of European eel are still unknown. We are the first to observe southward migrating sil

  11. The European Eel Anguilla anguilla (Pisces, Anguillidae. Native or Alien in the Black Sea?

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    Apostolos I. Apostolou

    2013-12-01

    Full Text Available In 2006 the Scientific, Technical and Economic Committee for Fisheries (STEFC of EU suggested the Black Sea region should be excluded from the list of natural areas, where the European eel (Anguilla anguilla is distributed. The basic conception of this idea was that the eels caught in the Black Sea region represent escaped specimens from fish farming in some Danubian countries. This article illustrates an effort to be given an indirect answer on the question if Black Sea is the end of natural distribution of European eel. The species is present but never been abundant in the region and do not represent an object of commercial fishing.

  12. Cycle évolutif de Bucephalus anguillae Spakulová, Macko, Berrilli & Dezfuli, 2002 (Digenea, Bucephalidae) parasite de Anguilla anguilla (L.).

    Science.gov (United States)

    Abdallah, L Gargouri-Ben; Maamouri, F

    2002-11-01

    The species of Bucephalus from the eel Anguilla anguilla of the north-eastern Tunisian lagoons was identified as B. anguillae which was recently described by Spakulová et al. (2002) from the Adriatic coast of Italy. In order to confirm that this eel digenean is distinct from B. polymorphus von Baer, 1827 present in other freshwater fishes, we investigated the life-cycle of this species. Surveys in the wild and experimental studies have shown that the life-cycle of B. anguillae is completed in brackish environments, with the lamellibranch Abra tenuis as the first intermediate host and the cyprinodontid fish Aphanius fasciatus as the second intermediate host. This life-cycle differs from that of B. polymorphus and can be considered as an additional argument for the distinction of these two morphologically similar species.

  13. Evolution of Microsatellite Loci of Tropical and Temperate Anguilla Eels

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    Mei-Chen Tseng

    2012-04-01

    Full Text Available Anguilla eels are divided into temperate and tropical eels, based on their major distributions. The present study collected two temperate eels, Anguilla japonica and Anguilla anguilla, and two tropical eels, Anguilla marmorata and Anguilla bicolor pacifica, to examine two questions: do temperate and tropical Anguilla eels have different genetic polymorphic patterns?; and do temperate Anguilla japonica and Anguilla anguilla have a closer relationship to each other than to tropical eels? In total, 274 sequences were cloned and sequenced from six conserved microsatellite loci to examine polymorphic patterns of these four catadromous eels. Different mutational events, including substitutions, and repeat-unit deletions and insertions, appeared in major regions, while different point mutations were observed in flanking regions. The results implied that parallel patterns of microsatellite sequences occurred within both tropical and temperate freshwater eels. Consensus flanking sequences of six homologous loci from each of the four species were constructed. Genetic distances ranged from 0.044 (Anguilla bicolor pacifica vs. Anguilla marmorata to 0.061 (Anguilla marmorata vs. Anguilla anguilla. The tree topology suggests the hypothesis of Anguilla japonica and Anguilla anguilla being a sister group must be rejected.

  14. Microsatellite variation between Japanese eel (Anguilla japonica) and European eel (Anguilla anguilla)

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Allelic variation in a total of 7 microsatellites was examined between elvers of freshwater eels (Anguilla japonica and Anguilla anguilla). The number of alleles at these loci ranged from 8 to 26. A single test of each locus revealed significant deficits of heterozygotes (P<0.01). Significant departure from expectations of Hardy-Weinberg equilibrium (HWE) was found for all loci within four subpopulations of A. japonica, which opposes the panmixia hypothesis of Schmidt. Also exact tests of population differentiation based on allelic frequency distribution disagree the hypothesis of random distribution of individuals among populations. Population structure among four populations of A. japonica was revealed with FST value of 0.009 8 (P=0.000 48; 10 000iteration). Pairwise matrixes of FST and RST showed a significant difference between two distantly related species-A. japonica and A. anguilla. Divergent time of the two species calculated by Goldstein method is over 2million years. The results may challenge the Schmidt's theory about the distribution of freshwater eels.

  15. Metal Accumulations in Water, Sediment, Crab (Callinectes sapidus) and Two Fish Species (Mugil cephalus and Anguilla anguilla) from the Köyceğiz Lagoon System-Turkey: An Index Analysis Approach.

    Science.gov (United States)

    Genç, Tuncer Okan; Yilmaz, Fevzi

    2017-08-01

    The concentrations of six metals (Hg, Cd, Cu, Pb, Cr and Zn) individual total metal load (IMBI) values and its relation to condition index were determined in water, sediment and tissues of crab (Callinectes sapidus) and two fish species (Mugil cephalus and Anguilla anguilla) inhabiting Köyceğiz Lagoon System. The average distribution of the IMBI values ranged from 0.033 to 0.265. Distribution patterns of IMBI in species follow the sequence: A. anguilla > M. cephalus > C. sapidus. Results showed that there are positive relationships between species sizes and metal levels in most cases. The concentrations of Pb in muscle in the three studied species were in all cases considerably higher than the maximum levels set by law. Average Cd, Cu and Zn values in M. cephalus were also higher than the limits proposed for fish by FAO/WHO, EC and TFC. Therefore, the human consumption of all analysed species is not recommended.

  16. How the body contributes to the wake in undulatory fish swimming: Flow fields of a swimming eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Müller, Ulrike K.; Smit, Joris; Stamhuis, Eize J.; Videler, John J.

    2001-01-01

    Undulatory swimmers generate thrust by passing a transverse wave down their body. Thrust is generated not just at the tail, but also to a varying degree by the body, depending on the fish's morphology and swimming movements. To examine the mechanisms by which the body in particular contributes to th

  17. How the body contributes to the wake in undulatory fish swimming: Flow fields of a swimming eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Müller, Ulrike K.; Smit, Joris; Stamhuis, Eize J.; Videler, John J.

    2001-01-01

    Undulatory swimmers generate thrust by passing a transverse wave down their body. Thrust is generated not just at the tail, but also to a varying degree by the body, depending on the fish's morphology and swimming movements. To examine the mechanisms by which the body in particular contributes to

  18. PAH Metabolites in Bile of European Eel (Anguilla anguilla) from Morocco.

    Science.gov (United States)

    Wariaghli, Fatima; Kammann, Ulrike; Hanel, Reinhold; Yahyaoui, Ahmed

    2015-12-01

    Environmental pollution of fish with organic contaminants is a topic of rising attention in Morocco. Polycyclic aromatic hydrocarbons (PAH) are prominent organic contaminants which are rapidly metabolized in fish. Their metabolites are accumulated in the bile fluid and can be used to assess PAH exposure. The two PAH metabolites 1-hydroxypyrene and 1-hydroxyphenanthrene were quantified in European eels (Anguilla anguilla) from two Moroccan river systems by high-performance liquid chromatography with fluorescence detection. Mean values ranged from 52 to 210 ng/mL 1-hydroxypyrene and from 61 to 73 ng/mL 1-hydroxyphenanthrene. The overall concentrations of PAH metabolites in eel from Morocco appeared moderate compared to eel from European rivers and coastal sites. The present study provides first information on concentrations of PAH metabolites in fish from Morocco.

  19. Reflex bradycardia does not influence oxygen consumption during hypoxia in the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Iversen, Nina Kerting; McKenzie, David; Malte, H.

    2010-01-01

    to measure cardiac output (Q) and heart rate (f H). MO2 was then measured by intermittent closed respirometry during sequential exposure to various levels of increasing hypoxia, to determine Pcrit. Each fish was studied before and after abolition of reflex bradycardia by intraperitoneal injection......Most teleost fish reduce heart rate when exposed to acute hypoxia. This hypoxic bradycardia has been characterised for many fish species, but it remains uncertain whether this reflex contributes to the maintenance of oxygen uptake in hypoxia. Here we describe the effects of inhibiting...... the bradycardia on oxygen consumption (MO2), standard metabolic rate (SMR) and the critical oxygen partial pressure for regulation of SMR in hypoxia (Pcrit) in European eels Anguilla anguilla (mean ± SEM mass 528 ± 36 g; n = 14). Eels were instrumented with a Transonic flow probe around the ventral aorta...

  20. Description of Bucephalus anguillae n. sp. (Trematoda: Bucephalidae), a parasite of the eel Anguilla anguilla (Anguillidae) from a brackish water lagoon of the Adriatic Sea.

    Science.gov (United States)

    Spakulová, Marta; Macko, Jozef K; Berrilli, Federica; Dezfuli, Bahram S

    2002-04-01

    The digenetic trematode Bucephalus anguillae n. sp. is described from the intestine of eel, Anguilla anguilla L., originating from a brackish water fish farm on the Italian coast of the Adriatic Sea. The new taxon is 1 of 12 Bucephalus species characterized by an anterior rhynchus surrounded by 7 tentacular appendages, each when fully protruded with 2 prongs. Scanning electron microscopy reveals, for the first time in a Bucephalus species, the crescent-shaped, unspined field located between the rhynchus and the dorsal tentacles. A comparison of B. anguillae n. sp. with 11 congeneric species revealed its remarkable similarity with B. polymorphus Baer, 1827; however, the new species has a larger cirrus sac, larger pharynx, vitelline gland fields not extending the level of pharynx, ovary located in the pharyngeal area rather than fairly posterior to pharynx, smaller testes, relatively wider rhynchus, and tegumental armature comprising slightly larger spines. Multivariate discriminant analyses confirmed a differentiation of B. anguillae from populations of B. polymorphus; the combination of 4 variables, namely cirrus sac length, pharynx width, cirrus sac width, and rhynchus width yielded a total separation of compared species.

  1. How the body contributes to the wake in undulatory fish swimming: flow fields of a swimming eel (Anguilla anguilla).

    Science.gov (United States)

    Müller, U K; Smit, J; Stamhuis, E J; Videler, J J

    2001-08-01

    Undulatory swimmers generate thrust by passing a transverse wave down their body. Thrust is generated not just at the tail, but also to a varying degree by the body, depending on the fish's morphology and swimming movements. To examine the mechanisms by which the body in particular contributes to thrust production, we chose eels, which have no pronounced tail fin and hence are thought to generate all their thrust with their body. We investigated the interaction between body movements and the flow around swimming eels using two-dimensional particle image velocimetry. Maximum flow velocities adjacent to the eel's body increase almost linearly from head to tail, suggesting that eels generate thrust continuously along their body. The wake behind eels swimming at 1.5 Ls(-1), where L is body length, consisted of a double row of double vortices with little backward momentum. The eel sheds two vortices per half tail-beat, which can be identified by their shedding dynamics as a start-stop vortex of the tail and a vortex shed when the body-generated flows reach the 'trailing edge' and cause separation. Two consecutively shed ipsilateral body and tail vortices combine to form a vortex pair that moves away from the mean path of motion. This wake shape resembles flow patterns described previously for a propulsive mode in which neither swimming efficiency nor thrust is maximised but sideways forces are high. This swimming mode is suited to high manoeuvrability. Earlier recordings show that eels also generate a wake reflective of maximum swimming efficiency. The combined findings suggest that eels can modify their body wave to generate wakes that reflect their propulsive mode.

  2. Acute toxicity, uptake and clearance of diazinon by the European eel, Anguilla anguilla (L.).

    Science.gov (United States)

    Sancho, E; Ferrando, M D; Andreu, E; Gamon, M

    1992-04-01

    The toxicity, accumulation, and elimination of diazinon were investigated for the european eel, Anguilla anguilla. The 24, 48, 72 and 96-h median lethal concentrations (LC50) were 0.16, 0.11, 0.09 and 0.08 mg/L, respectively. Fish exposed to sublethal concentration (0.042 mg/L) accumulated diazinon in liver and muscle tissues. Bioconcentration factors (BCF) of diazinon were 1850 in liver, and 775 in muscle over the 96-h exposure period. Upon removal from diazinon containing water the contaminated fish rapidly eliminated diazinon. The excretion rate constants of this insecticide were 0.108 h-1 for liver and 0.016 h-1 for muscle. Diazinon half-lives were 16.6 and 33.2 hours for liver and muscle, respectively.

  3. Diverse migration strategy between freshwater and seawater habitats in the freshwater eel genus Anguilla.

    Science.gov (United States)

    Arai, T; Chino, N

    2012-07-01

    The freshwater eels of the genus Anguilla, which are catadromous, migrate between freshwater growth habitats and offshore spawning areas. A number of recent studies, however, found examples of the temperate species Anguilla anguilla, Anguilla rostrata, Anguilla japonica, Anguilla australis and Anguilla dieffenbachii that have never migrated into fresh water, spending their entire life history in the ocean. Furthermore, those studies found an intermediate type between marine and freshwater residents, which appear to frequently move between different environments during their growth phase. The discovery of marine and brackish-water residents Anguilla spp. suggests that they do not all have to be catadromous, and it calls into question the generalized classification of diadromous fishes. There has been little available information, however, concerning migration in tropical Anguilla spp. Anguilla marmorata, shows three fluctuation patterns: (1) continuous residence in fresh water, (2) continuous residence in brackish water and (3) residence in fresh water after recruitment, while returning to brackish water. Such migratory patterns were found in other tropical species, Anguilla bicolor bicolor and Anguilla bicolor pacifica. In A. b. bicolor collected in a coastal lagoon of Indonesia, two further patterns of habitat use were found: (1) constantly living in either brackish water or sea water with no freshwater life and (2) habitat shift from fresh water to brackish water or sea water. The wide range of environmental habitat use indicates that migratory behaviour of tropical Anguilla spp. is facultative among fresh, brackish and marine waters during their growth phases after recruitment to the coastal areas. Further, the migratory behaviours of tropical Anguilla spp. appear to differ in each habitat in response to inter and intra-specific competition. The results suggest that tropical Anguilla spp. have a flexible pattern of migration, with an ability to adapt to various

  4. Food, feeding and growth of the eel (Anquilla anguilla L.) in a Dutch eutrophic lake

    NARCIS (Netherlands)

    Nie, de H.W.

    1988-01-01

    This thesis describes the food, foraging and growth of the eel (Anguilla anguilla). Attention is paid to the abundance and distribution of the food organisms and the feeding and growth of other fish species. The investigations were carried out in the Tjeukemeer (21 km2) in the northern part

  5. Angiotensin II dependent cardiac remodeling in the eel Anguilla anguilla involves the NOS/NO system

    DEFF Research Database (Denmark)

    Filice, Mariacristina; Amelio, Daniela; Garofalo, Filippo

    2017-01-01

    Angiotensin II (AngII), the principal effector of the Renin-Angiotensin System (RAS), plays an important role in controlling mammalian cardiac morpho-functional remodelling. In the eel Anguilla anguilla, one month administration of AngII improves cardiac performance and influences the expression...

  6. Hypercapnia adversely affects postprandial metabolism in the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Methling, C.; Pedersen, Per Bovbjerg; Steffensen, John Fleng

    2013-01-01

    The present study examined the effects of elevated CO2 partial pressure on the specific dynamic action (SDA) and ammonia excretion in European eel (Anguilla anguilla) following forced feeding. Two different hypercapnic scenarios were investigated; one inwhich pCO2 oscillated between 20 and 60 mm Hg...

  7. PCBs and the energy cost of migration in the European eel (Anguilla anguilla L.)

    NARCIS (Netherlands)

    Ginneken, van V.; Palstra, A.P.; Leonards, P.E.G.; Nieveen, M.; Murk, A.J.

    2009-01-01

    The effect of polychlorinated biphenyls (PCBs) on the energy consumption of fasting silver European eel (Anguilla anguilla L.) was studied over a 27-day period during which the animals were at rest or were swimming 800 km in Blazka swim tunnels. Three-year-old female hatchery eels (silver stage)

  8. Did lack of spawners cause the collapse of the European eel, Anguilla anguilla?

    NARCIS (Netherlands)

    Dekker, W.

    2003-01-01

    Since the 1980s, a 90% decline in recruitment of European eel, Anguilla anguilla (L.), has occurred across most of Europe. Whether the continental stock has equallydeclin ed is uncertain. This studyco mpiles available landings statistics since the beginning of the 20th century and identifies trends

  9. Freshwater and coastal migration patterns in the silver-stage eel Anguilla anguilla.

    Science.gov (United States)

    Barry, J; Newton, M; Dodd, J A; Lucas, M C; Boylan, P; Adams, C E

    2016-02-01

    The unimpeded downstream movement patterns and migration success of small female and male Anguilla anguilla through a catchment in north-west Europe were studied using an acoustic hydrophone array along the River Finn and into the Foyle Estuary in Ireland. Twenty silver-stage A. anguilla (total length, LT , range: 332-520 mm) were trapped 152 km upstream from a coastal marine sea-lough outlet and internally tagged with acoustic transmitters of which 19 initiated downstream migration. Migration speed was highly influenced by river flow within the freshwater (FW) compartment. Anguilla anguilla activity patterns were correlated with environmental influences; light, tidal direction and lunar phase all influenced the initiation of migration of tagged individuals. Migration speed varied significantly between upstream and lower river compartments. Individuals migrated at a slower speed in transitional water and sea-lough compartments compared with the FW compartment. While 88·5% survival was recorded during migration through the upper 121 km of the river and estuary, only 26% of A. anguilla which initiated downstream migration were detected at the outermost end of the acoustic array. Telemetry equipment functioned efficiently, including in the sea-lough, so this suggests high levels of mortality during sea-lough migration, or less likely, long-term sea-lough residence by silver A. anguilla emigrants. This has important implications for eel management plans.

  10. Musculoskeletal anatomy and feeding performance of pre-feeding engyodontic larvae of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Bouilliart, M.; Tomkiewicz, Jonna; Lauesen, P.

    2015-01-01

    Being part of the elopomorph group of fishes, Anguillidae species show a leptocephalus larval stage. However, due to largely unknown spawning locations and habitats of their earliest life stages, as well as their transparency, these Anguilla larvae are rarely encountered in nature. Therefore, inf...

  11. Growth and seasonal behavior of Anguilla anguilla in the River Minho tidal freshwater wetlands

    Directory of Open Access Journals (Sweden)

    Helena Correia

    2015-11-01

    Full Text Available The River Minho estuary, located on the northwest coast of the Iberian Peninsula, is a mesotidal estuary, partially mixed that during the period of high floods it tends to evolve towards a salt wedge estuary. The influence of spring tides extends approximately 40 km upstream and the tidal freshwater wetlands (TFWs are located in the upper 30 km. The Minho estuary is part of a Natura 2000 site, which includes the entire international section of the river being considered a very important river concerning migratory fish species. In the River Minho TFWs several fish species have ecological and economic value (Salmo trutta, Alosa fallax, Platichthys flesus, Anguilla anguilla, Salmo salar, Alosa alosa and Petromyzon marinus. European eel, A. anguilla, is in Appendix II of CITES list, that includes species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival. Between January 2007 and December 2014, in a selected semi-enclosed area of TFW and using 5 fyke-nets, were captured 1303 eels. All eels were measured and weighted, ocular index was determined and also marked with pit-tags and released in the same area. During these 8 years of work, around 15% of the total captured eels were recaptured once, less than 3% were recapture twice, less than 1% three times and 3 eels were recaptured 4 times. Eels marked in 2009 are until now the ones that were recaptured more times. Biological data as eel growth, seaward migration state, seasonal differences of by-catch will be crossed with abiotic data namely river flow, precipitation and water temperature.

  12. Tolerance of acute hypercapnic acidosis by the European eel ( Anguilla anguilla)

    DEFF Research Database (Denmark)

    McKenzie, D J; Taylor, E W; Dalla Valle, A Z;

    2002-01-01

    European eels ( Anguilla anguilla) were exposed sequentially to partial pressures of CO(2) in the water ( PwCO(2)) of 5, 10, 20, 40, 60 then 80 mm Hg (equivalent to 0.66-10.5 kPa), for 30 min at each level. This caused a profound drop in arterial plasma pH, from 7.9 to below 7.2, an increase in a...

  13. Metallothionein in liver of eels Anguilla anguilla from the Thames Estuary: an indicator of environmental quality?

    Science.gov (United States)

    Langston, W J; Chesman, B S; Burt, G R; Pope, N D; McEvoy, J

    2002-04-01

    The purpose of this study was to examine the role of the cysteine-rich protein metallothionein (MT) in the detoxification and metabolism of metals in livers of eels Anguilla anguilla from the Thames Estuary, and to assess the value of MT measurements in environmental monitoring. Hepatic MT levels and associated metal concentrations were determined in A. anguilla collected on three occasions during 1998 at sites along the tidal Thames (from freshwater to the sea) and also from a reference site (Tamar Estuary) in southwest England. MT was present at basal levels of 2 mg g(-1) dry weight (dw), predominantly in association with the essential metals Cu and Zn. MT concentrations were variable within each eel 'population' but were generally highest (up to 11 mg g(-1) in individual eels) at the more contaminated upper- and mid-estuarine sites in the Thames (e.g. Brentford and Kew). Lowest MT levels were those in eels from Blythe Sands at the mouth of the estuary. Season, sex, reproductive status and salinity may have influenced MT levels to some extent, although metals were the most significant factor. Hepatic MT concentrations were highly correlated with associated metal burdens (Zn, Cu, Ag and Cd),--notably reflecting Cu and Ag enrichment in the upper- and mid-estuary. With the exception of Zn, metals in the supernatant fraction of eel livers were primarily associated with MT. Proportions of Cu, Ag and Cd bound to MT increased as a function of accumulated metal burdens, with no indication of saturation. Thus, despite causing induction of MT, excess bioavailable Cu, Ag and Cd appear to be successfully detoxified in eels over the range of environmental contamination encountered along the Thames Estuary. Paradoxically, it may be argued from conventional doctrine that the presence of raised levels of MT, at upstream sites, constitutes a response to contamination and, by definition, signals that the fish are affected by metals; however, obvious signs of deleterious effects

  14. Anguillicola crassus (Nematoda, Dracunculoidea) infections of European eel (Anguila anguilla) in the Netherlands : epidemiology, pathogenensis and pathobiology

    NARCIS (Netherlands)

    Haenen, O.L.M.

    1995-01-01


    In the 1980s an eel parasitic nematode, Anguillicola crassus (Nematoda, Dracunculoidea), which infects the swimbladder of European eels ( Anguilla anguilla ) and other freshwater fish species, was introduced into The Netherlands. This thesis

  15. Chemical elements in the muscle tissues of European eel (Anguilla anguilla) from selected lakes in Latvia.

    Science.gov (United States)

    Rudovica, Vita; Bartkevics, Vadims

    2015-10-01

    Fish is a significant source of essential nutrients, as well as toxic elements in the human diet. Concentration of 17 elements was determined in muscles of eels (Anguilla anguilla) collected from five fishing lakes in the territory of Latvia. The concentration of main elements determined in muscle tissues varied within the following ranges: for Pb, 0.019-0.047; Cd, 0.0051-0.011; Hg, 0.13-0.36; Cu, 0.76-0.92; Zn, 28-42; and As, 0.13-0.23 mg kg(-1) wet weight. A positive correlation was revealed between the concentration of Hg in muscles and fish length in inland lakes. Concentration of metals in muscle tissues of eels from brackish coastal and inland lakes was without statistically significant difference. This research demonstrated that the elemental content of Cd and Pb in muscles of the examined fish was lower than the maximum allowed threshold set by the European Union legislation. Mercury content was over the threshold limit for all the analyzed eels if to compare with the Water Framework Directive Environmental Quality Standards. On other side, only 7% of analyzed fish have indicated values that are over threshold limits for mercury established by the European Union food legislation. The current study contributes to the implementation of Water Framework Directive in Latvia by collection of information necessary for the further protection measures of waters. To our knowledge, this study provides the first data on multielemental bioaccumulation in muscle tissues of European eels collected from fishing lakes of Latvia.

  16. Survival and progression rates of large European silver eel Anguilla anguilla in late freshwater and early marine phases

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Thorstad, Eva B.; Koed, Anders;

    2010-01-01

    The population of European silver eel Anguilla anguilla has declined tremendously in the last decades. The cause of this decline is unknown, and it is necessary to investigate the migratory behaviour and survival rates of silver eels during the reproductive migration in order to understand...... was high in fresh water. However, 60% of eels were lost in the inner and outer fjord, supporting the hypothesis that mortality is large in the early phase of the marine migration and that fishing may be a major cause of mortality of silver eels. There was no indication that the slowest......-migrating individuals were more prone to fishing mortality than the faster-migrating individuals. Progression rate increased as the eels proceeded downriver and out of the fjord. The migration was predominantly nocturnal, both in the river and fjord. Based on the available evidence, a considerable increase in eel...

  17. Tagging the European eel Anguilla anguilla (L.) with coded wire tags

    DEFF Research Database (Denmark)

    Thomassen, S.; Pedersen, Michael Ingemann; Holdensgaard, G.

    2000-01-01

    The coded wire tag (CWT) system was examined as a possible tool for tagging European eels (Anguilla anguilla). Two size groups of eels (3.8 and 10.2 g) were tagged with CWTs in the dorsal musculature, Tag loss 28 days after tagging was 3.1% for the small and 0.7% for the large groups of eels....... Of the tag loss in the small eels, 61% were lost during the first 2 h after tagging. In the small group, eels that lost tags were significantly (P...

  18. Ichthyodinium identified in the eggs of European eel (Anguilla anguilla) spawned in captivity

    DEFF Research Database (Denmark)

    Sørensen, Sune Riis; Tomkiewicz, Jonna; Skovgaard, A.

    2014-01-01

    A presumed parasitic protozoan was found in the eggs of European eel obtained from an experiment on captive breeding of eel, Anguilla anguilla, based on silver eels from a freshwater lake in the northern part of Denmark. Gross morphology of the organism was comparable to that of early stages...... genotypes: one occurring in the Atlantic Ocean and adjacent coastal waters and one in the Pacific Ocean area. The inclusion of several GenBank-derived environmental gene sequences, from the Caribbean Sea, revealed to represent Ichthyodinium, suggesting that this parasite genus is ubiquitous in the World...

  19. A physiologically based toxicokinetic (PBTK) model for moderately hydrophobic organic chemicals in the European eel (Anguilla anguilla)

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus [Department of Ecosystem Analysis, Institute for Environmental Research, ABBt — Aachen Biology and Biotechnology, RWTH Aachen University, Aachen (Germany); Freese, Marko; Pohlmann, Jan-Dag; Kammann, Ulrike [Thünen Institute of Fisheries Ecology, Hamburg (Germany); Preuss, Thomas G. [Environmental Biology and Chemodynamics, Institute for Environmental Research, ABBt — Aachen Biology and Biotechnology, RWTH Aachen University, Aachen (Germany); Buchinger, Sebastian; Reifferscheid, Georg [Federal Institute of Hydrology (BFG), Department G3: Biochemistry, Ecotoxicology, Koblenz (Germany); Beiermeister, Anne; Hanel, Reinhold [Thünen Institute of Fisheries Ecology, Hamburg (Germany); Hollert, Henner, E-mail: Henner.hollert@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, ABBt — Aachen Biology and Biotechnology, RWTH Aachen University, Aachen (Germany); State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing (China); College of Resources and Environmental Science, Chongqing University, Chongqing (China); Key Laboratory of Yangtze Water Environment, Ministry of Education, Tongji University, Shanghai 200092 (China)

    2015-12-01

    The European eel (Anguilla anguilla) is a facultatively catadromous fish species with a complex life cycle. Its current population status is alarming: recruitment has decreased drastically since the 1980s and its stock is still considered to be outside safe biological limits. Although there is no consensus on the reasons for this situation, it is currently thought to have resulted from a combination of different stressors, including anthropogenic contaminants. To deepen our understanding of the processes leading to the accumulation of lipophilic organic contaminants in yellow eels (i.e. the feeding, continental growth stage), we developed a physiologically based toxicokinetic model using our own data and values from the literature. Such models can predict the uptake and distribution of water-borne organic chemicals in the whole fish and in different tissues at any time during exposure. The predictive power of the model was tested against experimental data for six chemicals with n-octanol-water partitioning coefficient (log K{sub ow}) values ranging from 2.13–4.29. Model performance was excellent, with a root mean squared error of 0.28 log units. This model has the potential to help identify suitable habitats for restocking under eel management plans. - Highlights: • A PBTK model was developed for European eel (Anguilla anguilla). • Own experimental data and data from the literature were used for parameterization. • The predictive power of the model was excellent, with RMSE of 0.28 log units. • The developed model can be amended with sub-models for dietary and dermal exposure.

  20. Effects of dietary fatty acid composition on metabolic rate and responses to hypoxia in the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    McKenzie, D.J.; Piraccini, G.; Piccolella, M.

    2000-01-01

    European eels (Anguilla anguilla, L.) were fed on a commercial diet supplemented either with 15% by dry feed weight of menhaden oil (MO), an oil rich in highly unsaturated fatty acids of the n-3 series (n-3 HUFA), or with 15% by dry feed weight of coconut oil (CO), an oil composed primarily...

  1. The health status of European silver eels, Anguilla anguilla, in the Dutch River Rhine Watershed and lake IJsselmeer

    NARCIS (Netherlands)

    Haenen, O.L.M.; Lehmann, J.; Engelsma, M.Y.; Stürenberg, F.J.; Roozenburg, I.; Kerkhoff, S.; Klein Breteler, J.G.P.

    2010-01-01

    The worldwide decline of the eel population is thought to be caused by several factors, among which eel diseases. To investigate diseases of European silver eels Anguilla anguilla in the Netherlands, in Nov–Dec 2004 12 silver eels, and in Aug–Dec 2005 80 eels were caught in downstream parts (rivers)

  2. Differential expression of skin mucus C-type lectin in two freshwater eel species, Anguilla marmorata and Anguilla japonica.

    Science.gov (United States)

    Tsutsui, Shigeyuki; Yoshinaga, Tatsuki; Komiya, Kaoru; Yamashita, Hiroka; Nakamura, Osamu

    2016-08-01

    Two types of lactose-specific lectins, galectin (AJL-1) and C-type lectin (AJL-2), were previously identified in the mucus of adult Anguilla japonica. Here, we compared the expression profiles of these two homologous lectins at the adult and juvenile stages between the tropical eel Anguilla marmorata and the temperate eel A. japonica. Only one lectin, predicted to be an orthologue of AJL-1 by LC-MS/MS, was detected in the mucus of adult A. marmorata. We also found that an orthologous gene to AJL-2 was expressed at very low levels, or not at all, in the skin of adult A. marmorata. However, we detected the gene expression of an AJL-2-orthologue in the skin of juvenile A. marmorata, and a specific antibody also detected the lectin in the juvenile fish epidermis. These findings suggest that expression profiles of mucosal lectins vary during development as well as between species in the Anguilla genus.

  3. Determination of polybrominated diphenyl ethers in fish tissues by matrix solid-phase dispersion and gas chromatography coupled to triple quadrupole mass spectrometry: case study on European eel (Anguilla anguilla) from Mediterranean coastal lagoons.

    Science.gov (United States)

    Labadie, Pierre; Alliot, Fabrice; Bourges, Catherine; Desportes, Annie; Chevreuil, Marc

    2010-08-24

    This paper describes the development and validation of an analytical methodology to determine 28 polybrominated diphenyl ethers (PBDEs) in European eel (Anguilla anguilla) tissues using matrix solid-phase dispersion (MSPD) and gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQ-MS/MS). A total of 28 PBDEs were targeted, including tri- to deca-brominated congeners. The robustness and effectiveness of the proposed sample preparation procedure was demonstrated in lipid-rich eel tissues. The use of batch MSPD with activated silica gel and H(2)SO(4)-impregnated silica gel, followed by H(2)SO(4) digestion and multilayer cartridge clean-up allowed for complete lipid removal and eliminated matrix effects during GC-QQQ-MS/MS analysis. The average PBDE recoveries from eel muscle samples spiked with PBDEs at two levels were in the range 56.2-119.0%. Precision was satisfactory since relative standard deviations were lower than 19.6%, regardless of spike level, and method quantification limits ranged between 1 and 170 pg g(-1) (wet weight). The method demonstrated its successful application for the analysis of eel samples from two coastal lagoons located on the western French Mediterranean coast. All samples tested positive, but for tri- to hexa-brominated congeners only and total PBDE levels observed in this study were in the range 0.08-1.80 ng g(-1) wet weight.

  4. Development of a broodstock diet to improve developmental competence of embryos in European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Støttrup, Josianne Gatt; Tomkiewicz, Jonna; Jacobsen, Charlotte

    2016-01-01

    We examined the effect of dietary arachidonic acid (ARA) and eicosapentaenoic acid (EPA) on the production of embryos and hatched larvae in the European eel, Anguilla anguilla. Two diets with high and intermediate levels of ARA and low and intermediate levels of EPA (Feed 1: ARA 1.9%, EPA 4.......2%; Feed 2: ARA 1.2%, EPA 5.1% of total fatty acids) were tested against a commercial diet (DE: ARA: 0.5%, EPA: 8.2% of total fatty acids). After 24 weeks of feeding, ARA levels in the muscles and ovaries increased to 0.9% and 1.3% of total fatty acids, respectively, in Feed 1 and were significantly higher...... highest (1.1% of total fatty acids) in the diet with highest ARA levels (Feed 1)....

  5. Reproductive potential of silver European eels (Anguilla anguilla migrating from Vistonis Lake (Northern Aegean Sea, Greece

    Directory of Open Access Journals (Sweden)

    R. MACNAMARA

    2014-06-01

    Full Text Available The European eel (Anguilla anguilla, once abundant throughout much of Europe and North Africa, has recently been classified as critically endangered. Information on its biology from the eastern Mediterranean is lacking, especially in relation to spawner quality. Therefore, silver eels were sampled during their seaward spawning migration from Vistonis Lake in Greece. Characteristics linked to reproductive output and success (i.e. body size and condition, sex ratio, silvering, Anguillicola crassus infection, fecundity and oocyte diameter were examined. The lake produced large (687–1138 mm, exclusively female silver eels, 61.7% of which were infected by A. crassus. Silver eel fecundity, the first estimates from the southern part of the species range, was positively related to body length (R2 = 0.693; P < 0.001 and body weight (R2 = 0.731; P < 0.001. Fecundity did not differ between A. crassus infected and uninfected silver eels, but Greek silver eels were significantly more fecund than those in north-west Europe. The reproductive potential of Vistonis Lake silver eels and their contribution to the A. anguilla spawning stock is discussed.

  6. PAH metabolites, GST and EROD in European eel (Anguilla anguilla) as possible indicators for eel habitat quality in German rivers.

    Science.gov (United States)

    Kammann, Ulrike; Brinkmann, Markus; Freese, Marko; Pohlmann, Jan-Dag; Stoffels, Sandra; Hollert, Henner; Hanel, Reinhold

    2014-02-01

    The stock of the European eel (Anguilla anguilla L.) continues to decline and has reached a new minimum in 2011. Poor health status of the spawners due to organic contaminants is one of the possible causes for this dramatic situation. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants, which are rapidly metabolized in vertebrates. EROD (ethoxyresorufin-O-deethylase) and GST (glutathione-S-transferase) are two enzymes involved in PAH detoxification in fish. In this study, PAH metabolites as well as EROD and GST activity in a large, comprising dataset of more than 260 migratory and pre-migratory eels from five large German river basin districts were used to describe PAH exposure and its metabolism as possible indicators for the habitat quality for eels. Eel from the river Elbe appear to be moderately contaminated with PAH. Highest mean values of PAH metabolites were analysed in fish from the river Rhine. However, the results suggest that contaminants such as PAH are metabolized in the fish and may have contributed to EROD activity in eels caught from the Elbe estuary to 600 km upstream. Since the eel's onset of cessation of feeding is closely linked to maturation and migration, we propose bile pigments as new indicators contributing to identify the proportion of migratory eel, which is crucial information for eel management plans. We showed that PAH metabolites normalized to bile pigments as well as EROD could be used to describe the habitat quality and might be suitable parameters in search for suitable stocking habitats.

  7. Standardization of fertilization protocols for the European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Butts, Ian; Sørensen, Sune Riis; Politis, Sebastian Nikitas

    2014-01-01

    % of the models variance. In conclusion, European eel eggs should be fertilized within 10min post-stripping using 2.5e+4 sperm per egg. Together, these findings will contribute to the development of European eel breeding technology and further our understanding on sperm biology and reproductive biology in fishes...

  8. Plecospondylic spinal column in the eel Anguilla anguilla

    NARCIS (Netherlands)

    Stolk, A.

    1956-01-01

    Several cases of deformities in the spinal column were described in fishes, viz. lordosis in the bitterling Rhodeus amarus) by ROTH (1922), in the minnow (Phoxinus phoxinus) by ROTH (1922), in the pike (Esox lucius) by ROTH (1922) and PLEHN (1924); kyphosis in the toothcarps (Cyprinodontidae) by

  9. Plecospondylic spinal column in the eel Anguilla anguilla

    NARCIS (Netherlands)

    Stolk, A.

    1956-01-01

    Several cases of deformities in the spinal column were described in fishes, viz. lordosis in the bitterling Rhodeus amarus) by ROTH (1922), in the minnow (Phoxinus phoxinus) by ROTH (1922), in the pike (Esox lucius) by ROTH (1922) and PLEHN (1924); kyphosis in the toothcarps (Cyprinodontidae) by ROT

  10. Mortality of silver eel (Anguilla anguilla migrating downstream through a small hydroelectric plant on the Drawa River in northern Poland

    Directory of Open Access Journals (Sweden)

    Dębowski Piotr

    2016-06-01

    Full Text Available The European eel, Anguilla anguilla L., is an endangered species. Barriers to its downstream spawning migration are one of the greatest threats this species faces. There are hundreds of hydroelectric plants (HEP on rivers in Poland (> 600, and thousands throughout Europe. Eel that pass through HEP turbines as they migrate downstream suffer high mortality, but this depends mainly on local and technical conditions. Silver eel mortality was estimated and the possibility of the fish bypassing the turbines was studied between November 2013 and June 2014 at a typical HEP in northern Poland. Two telemetry methods were used with 49 eel: passive integrated transponder (PIT system and acoustic telemetry. Fifty five percent of eel migrated downstream in fall 2013, soon after their release, and 45% migrated the next spring. The eel did not use the fish passes designed for upstream migration; thus, they were forced to go through the turbines, which resulted in 55% mortality. HEPs cause interruptions and delays in eel spawning migrations and are responsible for high eel mortality. This can make implementing an eel restitution plan difficult or even impossible in river systems with many barriers.

  11. Internal redistribution of radiolabelled silver among tissues of rainbow trout (Oncorhynchus mykiss) and European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Hogstrand, C.; Grosell, M.; Wood, C.M.

    2003-01-01

    Influence of water Ag(I) speciation on pharmacokinetics of Ag(I) during a post-exposure period was investigated in rainbow trout (Oncorhynchus mykiss) and European eel (Anguilla anguilla). The rainbow trout is sensitive to waterborne ionic Ag+ whereas the eel is tolerant. The fish were acclimated...... chloride water). Contents and concentrations of Ag-110m(l) in tissues and body fluids were then monitored over a 67-day post-exposure period in Ag(I)-free water of the same chloride levels. Changing the speciation of Ag(l) in the water had no effect on the whole body load of Ag-110m(I), but did result...... in differences in internal distribution. In trout, changing water Ag(I) speciation significantly altered elimination or accumulation of Ag(I) in several body compartments. Notably, trout exposed to AgClaq eliminated Ag-110m(l) from the kidney more quickly than trout exposed to Ag(l) primarily as Ag...

  12. Maximal oxygen consumption increases with temperature in the European eel (Anguilla anguilla) through increased heart rate and arteriovenous extraction

    Science.gov (United States)

    Claësson, Débora; Wang, Tobias; Malte, Hans

    2016-01-01

    Global warming results in increasing water temperature, which may represent a threat to aquatic ectotherms. The rising temperature affects ecology through physiology, by exerting a direct limiting effect on the individual. The mechanism controlling individual thermal tolerance is still elusive, but some evidence shows that the heart plays a central role, and that insufficient transport of oxygen to the respiring tissues may determine the thermal tolerance of animals. In this study, the influence of the heart in thermal limitation was investigated by measurements of aerobic scope in the European eel (Anguilla anguilla) together with measurements of cardiac output during rest and activity. Aerobic capacity was not limited by an acutely increased temperature in the European eel. Oxygen demand was met by an increase in heart rate and arteriovenous extraction. These findings suggest that thermal tolerance during exposure to acute temperature changes is not defined by oxygen transport capacity in the eel, and other mechanisms may play a central role in limiting thermal tolerance in these fish.

  13. The in vitro effect of bovine lactoferrin on the activity of organ leukocytes in rainbow trout (Oncorhynchus mykiss), European eel (Anguilla anguilla) and wels catfish (Silurus glanis).

    Science.gov (United States)

    Małaczewska, J; Wójcik, M; Wójcik, R; Siwicki, A K

    2010-01-01

    Lactoferrin (LF) is a glycoprotein found in milk, neutrophil granules, secretions and selected organs of mammals. Lactoferrin exhibits antibacterial, antiviral, fungicidal, immunoregulatory and other functions. Although fish are devoid of this protein and its cell receptors, LF effect on the immune mechanisms of fish has been demonstrated. The objective of this study was to investigate the effect of bovine lactoferrin, applied in vitro, on the activity of head kidney and spleen leukocytes in three freshwater fish species: rainbow trout (Oncorhynchus mykiss), European eel (Anguilla anguilla) and wels catfish (Silurus glanis). The obtained results validate LF beneficial effect on the respiratory burst of phagocytes in rainbow trout and wels catfish despite the fact that the potential killing activity against Aeromonas hydrophila was not stimulated in any of the studied species. Bovine lactoferrin enhanced the proliferation of T-lymphocytes in rainbow trout and European eel, as well as of B-lymphocytes in rainbow trout.

  14. Speciation and demographic history of Atlantic eels (Anguilla anguilla and A. rostrata) revealed by mitogenome sequencing.

    Science.gov (United States)

    Jacobsen, M W; Pujolar, J M; Gilbert, M T P; Moreno-Mayar, J V; Bernatchez, L; Als, T D; Lobon-Cervia, J; Hansen, M M

    2014-11-01

    Processes leading to speciation in oceanic environments without obvious physical barriers remain poorly known. European and American eel (Anguilla anguilla and A. rostrata) spawn in partial sympatry in the Sargasso Sea. Larvae are advected by the Gulf Stream and other currents towards the European/North African and North American coasts, respectively. We analyzed 104 mitogenomes from the two species along with mitogenomes of other Anguilla and outgroup species. We estimated divergence time between the two species to identify major events involved in speciation. We also considered two previously stated hypotheses: one where the ancestral species was present in only one continent but was advected across the Atlantic by ocean current changes and another where population declines during Pleistocene glaciations led to increasing vicariance, facilitating speciation. Divergence time was estimated to ∼3.38 Mya, coinciding with the closure of the Panama Gateway that led to reinforcement of the Gulf Stream. This could have advected larvae towards European/North African coasts, in which case American eel would be expected to be the ancestral species. This scenario could, however, not be unequivocally confirmed by analyses of dN/dS, nucleotide diversity and effective population size estimates. Extended bayesian skyline plots showed fluctuations of effective population sizes and declines during glaciations, and thus also lending support to the importance of vicariance during speciation. There was evidence for positive selection at the ATP6 and possibly ND5 genes, indicating a role in speciation. The findings suggest an important role of ocean current changes in speciation of marine organisms.

  15. Impairment of lipid storage by cadmium in the European eel (Anguilla anguilla)

    Energy Technology Data Exchange (ETDEWEB)

    Pierron, Fabien [UMR CNRS 5805 EPOC, Team GEMA, Universite Bordeaux 1 and CNRS, Place du Dr Peyneau, 33120 Arcachon (France); Baudrimont, Magalie [UMR CNRS 5805 EPOC, Team GEMA, Universite Bordeaux 1 and CNRS, Place du Dr Peyneau, 33120 Arcachon (France)]. E-mail: m.baudrimont@epoc.u-bordeaux1.fr; Bossy, Angelique [UMR CNRS 5805 EPOC, Team GEMA, Universite Bordeaux 1 and CNRS, Place du Dr Peyneau, 33120 Arcachon (France); Bourdineaud, Jean-Paul [UMR CNRS 5805 EPOC, Team GEMA, Universite Bordeaux 1 and CNRS, Place du Dr Peyneau, 33120 Arcachon (France); Brethes, Daniel [IBGC, UMR CNRS 5095, Universite Bordeaux 2 and CNRS, 1, rue Camille Saint Saens, 33077 Bordeaux Cedex (France); Elie, Pierre [Cemagref, Unite Ecosystemes Estuariens et Poissons Migrateurs Amphihalins, U.R. EPBX, Cemagref, 50 Avenue de Verdun, 33612 Cestas (France); Massabuau, Jean-Charles [UMR CNRS 5805 EPOC, Team GEMA, Universite Bordeaux 1 and CNRS, Place du Dr Peyneau, 33120 Arcachon (France)

    2007-03-10

    Because European silver eels (Anguilla anguilla) fast during their reproductive migration to the Sargasso Sea, the successful completion of their unusual life cycle depends on quantity of lipids stored beforehand. These lipids are mainly accumulated during the growth phase stage of the animals, called yellow eel, as triglycerides in muscle. They are then catabolized to provide sufficient energy to enable migration, gonad maturation and spawning. In the laboratory, we investigated the possible impact of cadmium on the lipid storage efficiency of yellow eels in order to evaluate the possible contribution of this pollutant to the reported decline of European eel populations. Eels were exposed to dissolved cadmium at nominal concentrations of 0 and 5 {mu}g L{sup -1} for 1 month. Cd toxicity was then examined by studying the activity and expression level of several enzymes involved in liver lipolysis and lipogenesis and by determining lipid content in muscle. Contaminated eels showed a lower body weight growth with a lower efficiency of lipid storage compared to controls. Using two complementary approaches, genetic and enzymatic, it was possible to conclude that this impairment is mainly explained by an increased utilisation of triglycerides since cadmium contamination did not trigger a reduced fatty acid synthesis. These observations suggest an increased fat consumption in presence of cadmium, which could compromise successful reproduction.

  16. Replicating phages in the epidermal mucosa of the eel (Anguilla anguilla

    Directory of Open Access Journals (Sweden)

    Miguel eCarda Diéguez

    2015-01-01

    Full Text Available In this work, we used the eel (Anguilla anguilla as an animal model to test the hypothesis of Barr et al. about the putative role of the epidermal mucosa as a phage enrichment layer. To this end, we analyzed the microbial content of the skin mucus of wild and farmed eels by using a metagenomic approach. We found a great abundance of replicating phages (concatemers in all the samples. They were assembled in four complete genomes of three Myovirus and one Podovirus. We also found evidences that ΦKZ and Podovirus phages could be part of the resident microbiota associated to the eel mucosal surface and persist on them over the time. Moreover, the viral abundance estimated by epiflorescent counts and by metagenomic recruitment from eel mucosa was higher than that of the surrounding water. Taken together, our results support the hypothesis that claims a possible role of phages in the animal mucus as agents controlling bacterial populations, including pathogenic species, providing a kind of innate immunity.

  17. Glutathione transferases from Anguilla anguilla liver: identification, cloning and functional characterization.

    Science.gov (United States)

    Carletti, Erminia; Sulpizio, Marilisa; Bucciarelli, Tonino; Del Boccio, Piero; Federici, Luca; Di Ilio, Carmine

    2008-10-20

    Glutathione transferases (GSTs) constitute a class of detoxifying enzymes involved in Phase II metabolism. Using GSH-affinity chromatografy followed by HPLC analysis, two GST isoforms were isolated from the Anguilla anguilla liver cytosol. The major GST belongs to the piscine-specific rho class and accounted for about 59% of total GST affinity eluted fraction, while the remaining 41% was represented by a Pi class GST. Both isoforms were cloned, heterologously expressed in Escherichia coli and their enzyme activities were characterized with respect to a broad spectrum of well-known GST substrates. Our data indicate that only a fraction of prototypical GST substrates are conjugated by these enzymes and that Pi class GST has higher specific activity than rho class GST against 1-chloro-2,4-dinitrobenzene (CDNB), ethracrynic acid, 4-nitroquinoline-1-oxide and p-nitrophenyl acetate while trans-2-nonenal is detoxified more efficiently by rho class GST. Analysis of the kinetics parameters of the conjugation against CDNB indicated that the utilization ratio K(cat)/K(m) is slightly higher for rho class GST with respect to pi class GSTs. Finally, to determine the potential for environmental inhibition of the GST isoforms, we examined the effect of the widely used herbicide atrazine as an inhibitor of catalytic activity. The inhibition studies revealed that atrazine was an effective inhibitor of GST-CDNB catalytic activities of both isoforms at micromolar concentrations, suggesting the sensitivity of these isoforms to pesticide inhibition at environmentally relevant concentrations.

  18. Epidemiology and pathology of Anguillicoloides crassus in European eel Anguilla anguilla from the Tagus estuary (Portugal).

    Science.gov (United States)

    Neto, Ana Filipa; Costa, José Lino; Costa, Maria José; Domingos, Isabel

    2010-02-17

    Infection of the European eel Anguilla anguilla by the swimbladder nematode Anguillicoloides crassus was investigated for the first time at 5 sampling sites in the Tagus estuary (Portugal). A total of 332 yellow eels were examined, revealing a prevalence of 56% and a mean intensity of 3.2 lumen worms per swimbladder. The effect of the host's sex and size on parasitism descriptors was studied. Only total length (TL) was considered a significant determinant, with larger eels harbouring a higher number of nematodes. Eels were parasitized in 4 of the 5 sampling sites, with prevalence values following the salinity gradient along the Tagus estuary. No signs of the nematode were observed in the most saline site. Variations in the intensity of infection were only apparent when a large geographic scale including a wide temperature range was considered. Although 68% of the analysed eels showed pathological damage to the swimbladder caused by the parasite, injuries were relatively reduced in comparison with other studies. No effect of the infection on the condition of the body and on liver condition was detected. However, considerable spleen enlargement was observed with increasing parasite load, which could be related to the bloodsucking activity of this nematode.

  19. A COMPUTATIONAL STUDY ON BACKWARD SWIMMING HYDRODYNAMICS IN THE EEL ANGUILLA ANGUILLA

    Institute of Scientific and Technical Information of China (English)

    HU Wen-rong; TONG Bin-gang; MA Hui-yang; LIU Hao

    2005-01-01

    Eels can perform both forward and backward undulatory swimming but few studies are seen on how eels propel themselves backward. A computational study on the unsteady hydrodynamics of the backward swimming in the eel anguilla anguilla is carried out and presented. A two-dimensional geometric model of the European eel body in its middle horizontal section is appropriately approximated by a NACA0005 airfoil. Kinematic data of the backward and forward swimming eel used in the computational modeling are based on the experimental results of the European eel. Present study provided the different flow field characteristics of three typical cases in the backward swimming, and confirmed the guess of Wu: When the eel swims steadily, the vortex centers extensive comparison between the backward and forward swimming further reveals that the controllable parameters, such as frequency, amplitude and wavelength of the traveling wave, have a similar influence on the propulsion performance as in forward swimming. But it is shown that the backward swimming does not be a "reversed" forward swimming one. The backward swimming does show significant discrepancy in the propulsion performance: utilization of a constant-amplitude wave profile enables larger force generation for maneuverability but with much lower propulsive efficiency instead of the linear-increasing amplitude wave profile in the forward swimming. The actual swimming modes eels choose is the best choice associated with their propulsive requirement, as well as their physiological and ecological adaptation.

  20. Cholinesterase activities and sensitivity to pesticides in different tissues of silver European eel, Anguilla anguilla.

    Science.gov (United States)

    Valbonesi, P; Brunelli, F; Mattioli, M; Rossi, T; Fabbri, E

    2011-11-01

    Cholinesterase (ChE) activities were characterized in silver European eel, Anguilla anguilla, grown in the brackish lagoon of Comacchio (Italy). All specimens were harvested at the "lavoriero", a traditional eel trapping weir that captures eels while leaving internal waters at the onset of reproductive migration. To our knowledge, no investigation on ChE was reported in silver eels. Therefore a first characterization of enzyme activity in muscle, brain, liver and plasma of silver eel was carried out, in the presence of different substrates, selective inhibitors, and four pesticides representative of the carbamate and organophosphate classes. Brain and white skeletal muscle showed similar ChE activities, 5- and 10-fold higher than those detected in liver and plasma, respectively. Km values of 0.31 and 0.30 mM, and Vmax values of 40.28 and 35.47 nmol min(-1) mg protein(-1) were obtained in brain and muscle ChE, respectively. Acetycholinesterase was the predominant ChE form in all tissues, as concluded by comparing the effects of BW 284c51, iso-OMPA and eserine. ChE activities in brain and muscle were significantly inhibited by in vitro treatment with pesticides, with the following order of potency: carbofuran>carbaryl>chlorpyrifos≥diazinon.

  1. Uptake and clearance of diazinon in different tissues of the European eel (Anguilla anguilla L.).

    Science.gov (United States)

    Sancho, E; Ferrando, M D; Gamón, M; Andreu-Moliner, E

    1994-03-01

    Acute toxicity effects of diazinon on European eel (Anguilla anguilla) was examined using short-term exposures in static conditions. The LC50 values were 0.16, 0.11, 0.09 and 0.08 mg/l at 24, 48, 72 and 96 h exposure, respectively. In addition, the eels were exposed to 0.042 mg/l of diazinon and bioaccumulation and clearance processes of this insecticide in liver, muscle and gill tissues were studied. Bioconcentration factor (BCF) of diazinon over 96 h exposure period was 1850 in liver, 875 in gill and 775 in muscle tissue. Diazinon elimination from the selected tissues was rapid. The excretion rate constants of this insecticide were 0.108 h-1 for liver, 0.055 h-1 for gill and 0.016 h-1 for muscle. Diazinon half-lives were calculated as 16.6, 33.2 and 27 h for liver, muscle and gill, respectively. Diazinon showed relatively short half-lives in eel tissues.

  2. Vulnerability Assessment of Selected Buildings Designated as Shelters: Anguilla.

    Science.gov (United States)

    Gibbs, Tony

    Educational facilities in the Caribbean often serve roles as shelters during natural hazards, but they often sustain as much damage as other buildings. This study investigated the physical vulnerability of schools located on Anguilla to wind forces, torrential rain, and seismic forces in order to provide relevant local agencies with some of the…

  3. Analyses of organochlorine pesticides residues in eels (Anguilla anguilla from Lake Garda using Gas chromatography coupled with Tandem Mass Spectrometry (GC-MS/MS.

    Directory of Open Access Journals (Sweden)

    Giuseppe Federico Labella

    2017-05-01

    Full Text Available Lake Garda is located in Insubria region, that is known for being the most populated and industrialized area of Italy (Camusso et al., 2001. Therefore, the Lake water, and also the fish species present, could be affected by environmental contamination.  European eel (Anguilla anguilla are considered as suitable matrix for biomonitoring environmental contaminants in European water (Belpaire et al., 2007, being widespread in many European waters and highly contaminated by lipophilic compounds, due to the high lipid content (up to 40% (Larsson et al., 1991. Moreover, eel is an edible species (its farming currently supplies approximately 45,000 tons/year (Nielsen et al., 2008, so it also represents a public health issue. Based on these considerations, the aim of this study was to evaluate the occurrence of fourteen organochlorine pesticides (OCs in forty-five eels (Anguilla anguilla from Lake Garda, using Accelerated Solvent Extraction (ASE procedure for the analytes extraction and Gas chromatography coupled with Tandem Mass Spectrometry (GC-MS/MS for the analysis of OCs. GC-MS/MS analysis was developed and validated according to the SANTE/11945/2015 guidelines.  Uncontaminated eel sample (previously checked for the presence of OCs and considered blank with a concentration of compounds < Limit of Detection were used for all procedure's optimization steps. For all the OCs analysed, satisfactory results were achieved. Regarding eel samples, several pesticides were detected, but DDTs (DDT and its metabolites were found with the highest prevalence (92 %. The concentration rage was from not detected (n.d. to 19000 ng g-1. Although DDTs levels in the environment are declining (Albaiges et al., 2011, they continue to bioaccumulate in tissues of human and animal and biomagnify in food chains.

  4. Endocrine and metabolic responses of Anguilla anguilla L. caged in a freshwater-wetland (Pateira de Fermentelos-Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Teles, M. [Biology Department, Aveiro University, 3810-193 Aveiro (Portugal)]. E-mail: mteles@bio.ua.pt; Pacheco, M. [Biology Department, Aveiro University, 3810-193 Aveiro (Portugal)]. E-mail: mpacheco@bio.ua.pt; Santos, M.A. [Biology Department, Aveiro University, 3810-193 Aveiro (Portugal)]. E-mail: monteiro@bio.ua.pt

    2007-01-01

    The present short-term in situ study was carried out in a freshwater-wetland - Pateira de Fermentelos - considered an enlargement of Certima River, in the centre of Portugal. This ecosystem is an important fishing and recreation place, receiving effluents from different origins namely, electroplating industrial effluents containing heavy metals, domestic wastes, as well as pesticides and fertilizers resulting from agriculture activities. The aim of the present research work was to monitor the effects induced by the contaminants present in Pateira de Fermentelos water, using Anguilla anguilla L. (European eel) as a bioindicator. The eels were caged for 48 h at four Pateira de Fermentelos sites, differing in their distances to the main known pollution source (Certima River): A (close to the lagoon entrance), B, C and D (the farthest from the Certima River). A reference site was selected near the Certima river spring. The following parameters were measured: liver ethoxyresorufin-O-deethylase (EROD) and alanine transaminase (ALT) activities, plasma levels of cortisol, 17{beta}-estradiol (E{sub 2}), thyroid-stimulating-hormone (TSH), free thyroxine (T4), free triiodothyronine (T3), as well as glucose and lactate. The erythrocytic nuclear abnormalities (ENA) frequency was also scored as a genotoxicity indicator. The results revealed increased plasma cortisol and glucose concentrations at all exposure sites, displaying a similar response pattern. Plasma T3 showed a significant decrease only at site A when compared to reference site, whereas plasma E{sub 2} increased at sites B and D when compared to all the other sites, including reference site. The present results indicate the Pateira de Fermentelos water contamination, demonstrating the usefulness of the adopted strategy.

  5. Neurotransmitters and putative neuromodulators in the gut of Anguilla anguilla (L.. Localizations in the enteric nervous and endocrine systems

    Directory of Open Access Journals (Sweden)

    A Veggetti

    2009-12-01

    Full Text Available The gut of silver eels (Anguilla anguilla L. was investigated in order to describe both the cholinergic and adrenergic intramural innervations, and the localization of possible accessory neuromediators. Histochemical reactions for the demonstration of nicotinamide adenine dinucleotide phosphate, reduced form-(NADPH-diaphorase and acetylcholinesterese (AChEase were performed, as well as the immunohistochemical testing of tyrosine hydroxylase, met-enkephalin, substance P, calcitonin gene-related peptide (CGRP, bombesin, vasoactive intestinal peptide (VIP, neuropeptide Y (NPY, somatostatin, cholecystokinin-octapeptide (CCK-8, serotonin, cholineacetyltransferase. The results evidenced a different pattern in comparison with other vertebrates, namely mammals, and with other fish. Both NADPH-diaphorase and AChEase activities were histochemically detected all along the gut in the myenteric plexus, the inner musculature and the propria-submucosa. Tyrosine hydroxylase immunoreactivity was observed in the intestinal tract only, both in the myenteric plexus and in the inner musculature. Several neuropeptides (metenkephalin, CGRP, bombesin, substance P, VIP, NPY, somatostatin were, in addition, detected in the intramural innervation; some of them also in epithelial cells of the diffuse endocrine system (met-enkephalin, substance P, NPY, somatostatin. Serotonin was only present in endocrine cells. Tyrosine hydroxylase immunoreactivity was present in localizations to those of similar NADPHdiaphorase- reactivity, and in the same nerve bundles in which substance P- and CGRP-likeimmunoreactivities were detectable in the intestinal tract. In addition, NADPH-diaphorase-reactive neurons showed an anatomical relationship with AChEase-reactive nerve terminals, and a similar relationship existed between the latter and substance P-like immunoreactivity.

  6. Sympatric spawning but allopatric distribution of Anguilla japonica and Anguilla marmorata: temperature- and oceanic current-dependent sieving.

    Directory of Open Access Journals (Sweden)

    Yu-San Han

    Full Text Available Anguilla japonica and Anguilla marmorata share overlapping spawning sites, similar drifting routes, and comparable larval durations. However, they exhibit allopatric geographical distributions in East Asia. To clarify this ecological discrepancy, glass eels from estuaries in Taiwan, the Philippines, Indonesia, and China were collected monthly, and the survival rate of A. marmorata under varying water salinities and temperatures was examined. The composition ratio of these 2 eel species showed a significant latitude cline, matching the 24 °C sea surface temperature isotherm in winter. Both species had opposing temperature preferences for recruitment. A. marmorata prefer high water temperatures and die at low water temperatures. In contrast, A. japonica can endure low water temperatures, but their recruitment is inhibited by high water temperatures. Thus, A. japonica glass eels, which mainly spawn in summer, are preferably recruited to Taiwan, China, Korea, and Japan by the Kuroshio and its branch waters in winter. Meanwhile, A. marmorata glass eels, which spawn throughout the year, are mostly screened out in East Asia in areas with low-temperature coastal waters in winter. During summer, the strong northward currents from the South China Sea and Changjiang River discharge markedly block the Kuroshio invasion and thus restrict the approach of A. marmorata glass eels to the coasts of China and Korea. The differences in the preferences of the recruitment temperature for glass eels combined with the availability of oceanic currents shape the real geographic distribution of Anguilla japonica and Anguilla marmorata, making them "temperate" and "tropical" eels, respectively.

  7. Subcellular partitioning of non-essential trace metals (Ag, As, Cd, Ni, Pb, and Tl) in livers of American (Anguilla rostrata) and European (Anguilla anguilla) yellow eels.

    Science.gov (United States)

    Rosabal, Maikel; Pierron, Fabien; Couture, Patrice; Baudrimont, Magalie; Hare, Landis; Campbell, Peter G C

    2015-03-01

    We determined the intracellular compartmentalization of the trace metals Ag, As, Cd, Ni, Pb, and Tl in the livers of yellow eels collected from the Saint Lawrence River system in Canada (Anguilla rostrata) and in the area of the Gironde estuary in France (Anguilla anguilla). Differential centrifugation, NaOH digestion and thermal shock were used to separate eel livers into putative "sensitive" fractions (heat-denatured proteins, mitochondria and microsomes+lysosomes) and detoxified metal fractions (heat-stable peptides/proteins and granules). The cytosolic heat-stable fraction (HSP) was consistently involved in the detoxification of all trace metals. In addition, granule-like structures played a complementary role in the detoxification of Ni, Pb, and Tl in both eel species. However, these detoxification mechanisms were not completely effective because increasing trace metal concentrations in whole livers were accompanied by significant increases in the concentrations of most trace metals in "sensitive" subcellular fractions, that is, mitochondria, heat-denatured cytosolic proteins and microsomes+lysosomes. Among these "sensitive" fractions, mitochondria were the major binding sites for As, Cd, Pb, and Tl. This accumulation of non-essential metals in "sensitive" fractions likely represents a health risk for eels inhabiting the Saint Lawrence and Gironde environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Thyroid endocrine status of wild European eels (Anguilla anguilla) in the Loire (France). Relationships with organic contaminant body burdens.

    Science.gov (United States)

    Couderc, M; Marchand, J; Zalouk-Vergnoux, A; Kamari, A; Moreau, B; Blanchet-Letrouvé, I; Le Bizec, B; Mouneyrac, C; Poirier, L

    2016-04-15

    In teleost fish, thyroid function is involved in various critical physiological processes. Given the complexity of the hypothalamo-pituitary-thyroid (HPT) axis, a large number of genes and proteins can be the potential target of endocrine-disrupting compounds (EDCs). The aim of this study was to evaluate, in yellow and silver European eels (Anguilla anguilla), potential effects of EDCs on thyroid status by analyzing the associations between EDC body burdens and thyroid hormones (THs). In yellow individuals, greater free T3/T4 ratios (FT3/FT4) and lower plasma FT4 levels were associated with greater concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as highlighted by significant correlations with many congeners. Few positive relationships with alkylphenols were noticed. In contrast, silver eels usually exhibited less significant correlations between THs and contaminant loads. Expression of a series of genes involved in the HPT axis was also investigated in the silver individuals. Concerning mRNA expression in silver females, some main correlations were noticed: thyroid-stimulating hormone (TSHβ) gene expression was significantly correlated to numerous PCBs, and hepatic mRNA levels of deiodinase 2 (Deio 2) were negatively correlated to 2-hydroxyfluorene (2-OHF) and 2-naphtol (2-OHNa). Thyroid receptor (TRα and TRβ) mRNA levels exhibited weak negative correlations with some PBDEs in silver females and males. Hepatic vitellogenin (Vtg) mRNA levels were detected in all silver males but at lower levels than in silver females. In males, Vtg mRNA levels were positively associated to FT4/TT4. In silver females, strong positive correlations were found between congeners of PCBs, PBDEs and PFAS suggesting potential estrogenic effects. Overall, the observed results indicate that several organic contaminants, mainly dl-, ndl-PCBs and PBDEs, could be associated with changes in thyroid homeostasis in these fish, via direct or indirect

  9. Subcellular partitioning of non-essential trace metals (Ag, As, Cd, Ni, Pb, and Tl) in livers of American (Anguilla rostrata) and European (Anguilla anguilla) yellow eels

    Energy Technology Data Exchange (ETDEWEB)

    Rosabal, Maikel [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Pierron, Fabien [Université de Bordeaux, UMR EPOC CNRS 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Couture, Patrice [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Baudrimont, Magalie [Université de Bordeaux, UMR EPOC CNRS 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Hare, Landis [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Campbell, Peter G.C., E-mail: peter.campbell@ete.inrs.ca [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada)

    2015-03-15

    Highlights: • Handling of hepatic metals consistently involved cytosolic, thermostable ligands. • Granule-like fractions are also involved in the detoxification of Ni, Pb, and Tl. • Despite these sequestration mechanisms, metal detoxification is incomplete. • Along the metal gradient, concentrations increase in metal-sensitive fractions. • This increase could represent a toxicological risk for the yellow eels. - Abstract: We determined the intracellular compartmentalization of the trace metals Ag, As, Cd, Ni, Pb, and Tl in the livers of yellow eels collected from the Saint Lawrence River system in Canada (Anguilla rostrata) and in the area of the Gironde estuary in France (Anguilla anguilla). Differential centrifugation, NaOH digestion and thermal shock were used to separate eel livers into putative “sensitive” fractions (heat-denatured proteins, mitochondria and microsomes + lysosomes) and detoxified metal fractions (heat-stable peptides/proteins and granules). The cytosolic heat-stable fraction (HSP) was consistently involved in the detoxification of all trace metals. In addition, granule-like structures played a complementary role in the detoxification of Ni, Pb, and Tl in both eel species. However, these detoxification mechanisms were not completely effective because increasing trace metal concentrations in whole livers were accompanied by significant increases in the concentrations of most trace metals in “sensitive” subcellular fractions, that is, mitochondria, heat-denatured cytosolic proteins and microsomes + lysosomes. Among these “sensitive” fractions, mitochondria were the major binding sites for As, Cd, Pb, and Tl. This accumulation of non-essential metals in “sensitive” fractions likely represents a health risk for eels inhabiting the Saint Lawrence and Gironde environments.

  10. Musculoskeletal anatomy and feeding performance of pre-feeding engyodontic larvae of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Bouilliart, M.; Tomkiewicz, Jonna; Lauesen, P.;

    2015-01-01

    changes in the functionality of the feeding apparatus towards the active feeding phase, 3D data of joints, levers and muscles derived from the reconstructions were used to estimate bite and joint reaction forces (JRFs). Observing a maximum estimated bite force of about 65μN (and corresponding JRFs of 260μ......, information regarding the early life history of these larvae, including their exogenous feeding strategy and feeding performance, is rather scarce. To better understand the structural basis and functional performance of larval feeding in captivity, the functional morphology of the cranial musculoskeletal...... system in pre- and first-feeding engyodontic leptocephali of the European eel (Anguilla anguilla) was studied. A 3D reconstruction of the feeding apparatus (head of the leptocephali

  11. Occurrence of polycyclic aromatic hydrocarbons (PAHs) in mussel (Mytilus galloprovincialis) and eel (Anguilla anguilla) from Bizerte lagoon, Tunisia, and associated human health risk assessment

    Science.gov (United States)

    Barhoumi, Badreddine; El Megdiche, Yassine; Clérandeau, Christelle; Ameur, Walid Ben; Mekni, Sabrine; Bouabdallah, Sondes; Derouiche, Abdelkader; Touil, Soufiane; Cachot, Jérôme; Driss, Mohamed Ridha

    2016-08-01

    The aim of this study is to measure PAHs concentrations in mussels (Mytilus galloprovincialis) and fish (Anguilla anguilla) from the Bizerte lagoon (north Tunisia), and evaluate their distribution and sources, in order to provide a baseline of the state of PAH contamination in this lagoon and assess their human health risk. For this purpose, several native mussel and fish specimens were collected and analyzed using a high-performance liquid chromatography method with fluorescence detection for 15 EPA priority PAHs. PAHs levels in mussels and fish ranged from 107.4 to 430.7 ng g-1 dw and 114.5-133.7 ng g-1 dw, respectively. Naphthalene was the major component measured in mussels (31.5-272.6 ng g-1 dw) and fish (57.9-68.6 ng g-1 dw) and all specimens were classified as moderately contaminated. The PAHs composition pattern was similar for both species and was dominated by the presence of PAHs with 2- to 3-rings. The study of PAH ratios indicated a mixed petrogenic/pyrolytic origin. The health risks by consumption of these species was assessed and showed to present no threat to public health concerning PAH intakes. The results of this study would provide a useful aid for sustainable marine management in the region.

  12. Topography and ultrastructure of the tegument of Bucephalus anguillae (Digenea: Bucephalidae), a parasite of the European eel Anguilla anguilla (Osteichthyen: Anguillidae).

    Science.gov (United States)

    Filippi, Jean-José; Quilichini, Yann; Foata, Joséphine; Marchand, Bernard

    2010-12-01

    The tegumental ultrastructure of the intestinal fluke Bucephalus anguillae was studied with the use of scanning and transmission electron microscopy. The surface of the tegument is covered by transverse ridges from which protrude numerous closely packed, digitated, and claw-shaped spines. Cobblestone-like units of the tegument were observed on the crescent-shaped formation of the rhynchus and at the posterior part of the body. Three types of sensory structures were examined, i.e., 2 uniciliated receptors and 1 without cilia. As anterior-posterior differences were observed, particular attention was given to spines and sensory receptors. Spine insertion zones and average cilia length are variable between anterior and posterior tegument areas. Ultrastructural study revealed that the tegument of B. anguillae has a typical syncytial organization with a distal cytoplasm lying over a basal matrix and cytons below. Cytoplasmic bridges allowed transit of secretory vesicles and granules. Diagrams of spines and sensory receptors were made to help in understanding the nature of these structures.

  13. Enhancement of protective immunity in European eel(Anguilla anguilla)against Aeromonas hydrophila and Aeromonas sobria by a recombinant Aeromonas outer membrane protein

    Institute of Scientific and Technical Information of China (English)

    Ruizhang Guan; Jing Xiong; Wenshu Huang; Songlin Guo

    2011-01-01

    To develop a vaccine,which can simultaneously prevent the diseases caused by various pathogenic bacteria in fish,we try to find a conserved outer membrane protein(OMP)antigen from different bacterial pathogens.In this study,an OMP fragment of 747 by(named as Omp-G),whichwas highly conserved in seven Aeromonas OMP sequences from the NCBI database,was amplified by PCR from one Aeromonas sobria strain(1110)and two Aeromonas hydrophila strains(1327 and B33)with the designed specific primers.The sequence was cloned into pGEX-2T(6 × His-tag)vector,expressed in Escherichia coli system,and then the recombinant protein(named as rOmp-G)was purified with nickel chelating affinity chromatography.The purified romp-G showed a good immunogenicity in rabbits and well-conserved characteristics in these three pathogens by enzyme-linked immunosorbed assay.Furthermore,the rOmp-G also showed good immunogenicity in eels(Anguilla anguilla)for eliciting significantly increased specific antibodies(P<0.01),and providing higher protection efficiencies(P<0.05)after the pathogens challenge.The values of the relative percent survival in eels were 70% and 50% for two A.hydrophila strain challenge,and 75% for A.sobria strain challenge.This is the first report of a potential vaccination in eels that simultaneously provide protectiveness against different Aeromonas pathogens with a conserved partial OMP.

  14. The occurrence of persistent chlorinated and brominated organic contaminants in the European eel (Anguilla anguilla) in Irish waters.

    Science.gov (United States)

    McHugh, Brendan; Poole, Russell; Corcoran, John; Anninou, Pinelopi; Boyle, Brian; Joyce, Eileen; Barry Foley, M; McGovern, Evin

    2010-04-01

    The European eel (Anguilla anguilla) is a relatively high lipid, long lived species capable of living in a variety of brackish, fresh and marine habitats. As such, eels can accumulate organic pollutants and have been incorporated into environmental monitoring programs as a suitable "bioindicator" species for the determination of the levels of organic contaminants within different water bodies. The global eel stock is now in decline and while the cause of the collapse remains unidentified, it is likely to include a combination of anthropogenic mortality in addition to environmental degradation. This study provides valuable data on a range of contaminants (PCDD/Fs, PCBs, OCPs, PBDEs, HBCD, TBBPA and PBBs) and extractable lipid levels in eel muscle tissue collected from five Irish catchments. Extractable lipid levels were lower in the yellow eels compared to those in the silver eels. These levels were similar to those reported elsewhere and it has been posited that a decline in the lipid content in yellow eels may have consequences for the future viability of the stock. With the exception of higher substituted dioxins (especially OCDD), in three samples collected from one catchment (Burrishoole) in the West of Ireland, POP levels in general were determined to be low in eels from Irish waters compared to those in other countries.

  15. Uptake and Clearance of Diazinon in Different Tissues of the European Eel(Anguilla anguilla L.)

    Institute of Scientific and Technical Information of China (English)

    E.SANCHO; M.D.FERRANDO; 等

    1994-01-01

    Acute toxicity effects of diazinon on European eel(Anguilla anguilla)was examined using short-term exposures in static conditions.The LC50 values were 0.16,0.11,0.09and 0.08mg/l at 24,48,72 an 96h exposure,respectively.In addition,the eels were exposed to 0.042mg/l of diazinon and bioaccumulation and celearance processes of this insecticide in liver,muscle and gill tissues were studied.Bioconcentration factor(BCF)of diaxinon over 96h exposure period was 1850 in liver,875in gill and 775 in musele tissue.Diazinon elimination from the selected tissues was rapid.The excretion rate constants of this insecticide were 0.108h-1 for liver,0.055h1 for gill and 0.016H1 for muscle.Diazinon half-lives were calculated as 16.6,33.2 and 27h for liver,muscle and gill,respectively,Diazinon showed relatively short half-lives in eel tissues.

  16. European eel (Anguilla anguilla) genotoxic and pro-oxidant responses following short-term exposure to Roundup--a glyphosate-based herbicide.

    Science.gov (United States)

    Guilherme, S; Gaivão, I; Santos, M A; Pacheco, M

    2010-09-01

    The glyphosate-based herbicide, Roundup, is among the most used pesticides worldwide. Due to its extensive use, it has been widely detected in aquatic ecosystems representing a potential threat to non-target organisms, including fish. Despite the negative impact of this commercial formulation in fish, as described in literature, the scarcity of studies assessing its genotoxicity and underlying mechanisms is evident. Therefore, as a novel approach, this study evaluated the genotoxic potential of Roundup to blood cells of the European eel (Anguilla anguilla) following short-term (1 and 3 days) exposure to environmentally realistic concentrations (58 and 116 microg/l), addressing also the possible association with oxidative stress. Thus, comet and erythrocytic nuclear abnormalities (ENAs) assays were adopted, as genotoxic end points, reflecting different types of genetic damage. The pro-oxidant state was assessed through enzymatic (catalase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase) and non-enzymatic (total glutathione content) antioxidants, as well as by lipid peroxidation (LPO) measurements. The Roundup potential to induce DNA strand breaks for both concentrations was demonstrated by the comet assay. The induction of chromosome breakage and/or segregational abnormalities was also demonstrated through the ENA assay, though only after 3-day exposure to both tested concentrations. In addition, the two genotoxic indicators were positively correlated. Antioxidant defences were unresponsive to Roundup. LPO levels increased only for the high concentration after the first day of exposure, indicating that oxidative stress caused by this agrochemical in blood was not severe. Overall results suggested that both DNA damaging effects induced by Roundup are not directly related with an increased pro-oxidant state. Moreover, it was demonstrated that environmentally relevant concentrations of Roundup can pose a health risk for fish populations.

  17. Data for transcriptomic and iTRAQ proteomic analysis of Anguilla japonica gills in response to osmotic stress.

    Science.gov (United States)

    Tse, William Ka Fai; Sun, Jin; Zhang, Huoming; Lai, Keng Po; Gu, Jie; Sheung Law, Alice Yu; Yee Yeung, Bonnie Ho; Ching Chow, Sheung; Qiu, Jian-Wen; Wong, Chris Kong Chu

    2015-06-01

    This article contains data related to the two research articles titled Transcriptomic and iTRAQ proteomic approaches reveal novel short-term hyperosmotic stress responsive proteins in the gill of the Japanese eel (Anguilla japonica) (Tse et al. [1]) and iTRAQ-based quantitative proteomic analysis reveals acute hypo-osmotic responsive proteins in the gills of the Japanese eel (Anguilla japonica) (Tse et al. [2]). The two research articles show the usefulness of combining transcriptomic and proteomic approaches to provide molecular insights of osmoregulation mechanism in a non-model organism, the Japanese eel. The information presented here combines the raw data from the two studies and provides an overview on the physiological functions of fish gills.

  18. A comparison of metal concentrations in the tissues of yellow American eel (Anguilla rostrata) and European eel (Anguilla anguilla).

    Science.gov (United States)

    Pannetier, Pauline; Caron, Antoine; Campbell, Peter G C; Pierron, Fabien; Baudrimont, Magalie; Couture, Patrice

    2016-11-01

    Historically abundant and widespread, populations of Atlantic eels have suffered a sharp decline in recent decades, in the ranges 40-80% and 90-99% for American and European eels, respectively. As a result, American eels are now classified as threatened, whereas European eels are considered to be in critical danger of extinction. Several causes have been identified as likely contributors of this decline, including overfishing, obstacles to migration (hydroelectric dams), climate change and habitat contamination. In the context of a larger project investigating the role of organic and inorganic contaminants in this decline, in this study, we measured the liver, kidney and muscle concentrations of essential (Cu, Se and Zn) and non-essential (Ag, As, Cd, Cr, Hg, Ni and Pb) metals in eels sampled at four sites in the South-West of France and four sites in Eastern Canada varying in contamination. Tissue concentrations of Cd, Hg and Se increased with fish size and age. Tissue metal concentrations generally reflected the contamination of their sampling sites. This was the case for Ag, As, Cd, Cu, Hg, Pb and Se. Comparison of tissue concentrations of these metals with the toxicological literature suggests that all of them except As could pose a risk to the health of eels from the most contaminated sites. In particular, European eels may be particularly at risk of Cd and Pb toxicity. Globally, our study suggests that a substantial accumulation of inorganic contaminants in the tissues of both eel species at sites contaminated by historical anthropogenic inputs may play a role in their decline.

  19. Characterization of PAMP/PRR interactions in European eel (Anguilla anguilla) macrophage-like primary cell cultures.

    Science.gov (United States)

    Callol, A; Roher, N; Amaro, C; MacKenzie, S

    2013-10-01

    The eel (Anguilla anguilla) has been identified as a vulnerable species with stocks dramatically declining over the past decade. In an effort to support the species from overfishing of wild stocks increased interest in eel aquaculture has been notable. In order to expand the scarce knowledge concerning the biology of this species significant research efforts are required in several fields of biology. The development of cell culture systems to study the immune response is a key step towards an increased understanding of the immune response and to develop resources to support further study in this threatened species. Macrophages are one of the most important effector cells of the innate immune system. The capacity to engulf pathogens and orchestrate the immune response relies on the existence of different surface receptors, such as scavenger receptors and toll-like receptors. We have developed and described an eel macrophage-like in vitro model and studied its functional and transcriptomic responses. Macrophage-like cells from both head kidney and purified peripheral blood leukocytes were obtained and phagocytic activity measured for different whole bacteria and yeast. Moreover, based on PAMP-PRR association the innate immune response of both head kidney and PBL derived macrophage-like cells was evaluated against different pathogen-associated molecular patterns (PAMPs). Results highlight that peptidoglycan stimulation strongly induces inflammatory mRNA expression reflected in the up-regulation of pro-inflammatory genes IL1β and IL18 in PBL derived cells whereas IL8 is upregulated in head kidney derived cells. Furthermore TLR2 mRNA abundance is regulated by all stimuli supporting a multifunctional role for this pathogen recognition receptor (PRR) in eel macrophage-like cells.

  20. Influence of site, season, silvering stage, and length on the parasites of the European eel Anguilla anguilla in two Mediterranean coastal lagoons of the island of Corsica, France using indicator species method.

    Science.gov (United States)

    Filippi, Jean-José; Quilichini, Yann; Foata, Joséphine; Marchand, Bernard

    2013-08-01

    The parasites of 425 European eels, Anguilla anguilla, were studied between 2009 and 2012 in two Mediterranean coastal lagoons of the island of Corsica, France. An indicator value (IndVal) method was used for analysis, which combines measures of fidelity and specificity. Because of its resilience to detect changes in abundance, IndVal is an effective ecological bioindicator. The IndVal method demonstrated that site, season, silvering stage, and length could influence the occurrence of parasite species in European eel. A randomization test identified ten parasite species as having a significant indicator value for site (lagoons differed principally in salinity: oligohaline to polyhaline for the Biguglia lagoon and polyhaline to euhaline for the Urbino lagoon; the digeneans Bucephalus anguillae and Lecithochirium musculus, the cestodes Bothriocephalus claviceps, Proteocephalus macrocephalus, and larvae of Myzophyllobothrium sp., the nematodes Anguillicoloides crassus, and encysted larvae of Contracaecum sp., the acanthocephalan Acanthocephaloides incrassatus, the monogenean Pseudodactyogyrus anguillae, and the copepod Ergasilus gibbus); one parasite species for the spring season (the acanthocephalan A. incrassatus); six parasite species for silvering stage (yellow, pre-silver, silver; the trematodes B. anguillae and Deropristis inflata, encysted larvae of the nematode Contracaecum sp., the acanthocephalan A. incrassatus, the monogenean P. anguillae, and the copepod E. gibbus); and three parasite species for some of the five length classes (the cestode P. macrocephalus, encysted larvae of the nematode Contracaecum sp., and the monogenean P. anguillae). Data for species composition and infection levels should help to improve the management of parasitism in the populations of European eels.

  1. Micro-PIXE study of whole otolith of Anguilla japonica at elver stage

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Guo, H.; Wei, K.; Tang, W. [Institute of Life Science, Shanghai Fisheries University, Shanghai 200090 (China); Satoh, T.; Ohkubo, T.; Yamazaki, A.; Takano, K.; Kamiya, T. [Takasaki Advanced Radiation Research Institute, JAEA, Gunma 370-1292 (Japan); Shen, H., E-mail: haoshen@fudan.edu.c [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Yang, M.; Mi, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China)

    2010-06-15

    Strontium and calcium contents, within the otolith of Anguilla japonica, were measured by external micro-PIXE. According to the measured metamorphic checks, each otolith was divided into three stages. Comparing with the Sr:Ca ratios in stage 2, the ratios in stage 1 had two different trends. Among these fish, it may reflect their maternal condition was not the same. The ratios in stage 3 which was corresponding to the estuarine habitat were smaller than that in any other stage which was corresponding to the ocean habitat in each otolith. Suggested by our results, the eels from the spawning site may separate into two groups when they are near to the south of Taiwan, and then move to the different estuaries in China. It could be proposed that, in general, the migration direction is from south to north along the east coast in China.

  2. Oxidative stress and genotoxic effects in gill and kidney of Anguilla anguilla L. exposed to chromium with or without pre-exposure to beta-naphthoflavone.

    Science.gov (United States)

    Ahmad, Iqbal; Maria, V L; Oliveira, M; Pacheco, M; Santos, M A

    2006-09-19

    Fish in the aquatic environment can be subjected to a multipollution state and the occurrence of sequential exposures is an important aspect of eco-toxicological research. In this context, a preceding exposure can affect a toxic response to a subsequent exposure. Therefore, the current study was based on sequential exposures, viz. to a PAH-like compound (beta-naphthoflavone, BNF) followed by a heavy metal (chromium, Cr), focusing on the assessment of oxidative stress responses and their role in induction of genotoxicity. Oxidative stress responses in gill and kidney were investigated in European eel (Anguilla anguilla L.), and measured as lipid peroxidation (LPO), glutathione peroxidase (GPX), catalase (CAT) and glutathione S-transferase (GST) activity, and reduced glutathione (GSH) concentration, whereas genotoxicity was measured as DNA strand breakage. Fish were exposed for 24 h to two Cr concentrations (100 microM, 1 mM), with or without pre-exposure to BNF (2.7 microM, 24 h). In gill, a GSH decrease was observed along with loss of DNA integrity at all exposure conditions except at the lowest Cr concentration, showing a crucial role of GSH over genotoxicity. Moreover, sporadic induction of antioxidant enzymes was not effective in the protection against genotoxicity. However, a different mechanism seems to occur in kidney, since the loss of DNA integrity detected for all exposed groups was not accompanied by alterations in antioxidant levels. With regards to peroxidative damage, both organs showed an LPO increase after sequential exposure to BNF and 100 microM Cr. However, no association between LPO induction and antioxidant responses could be established, showing that LPO is not predictable solely on the basis of antioxidant depletion. The interference of BNF pre-exposure with the response of organs to Cr showed a marked dependence on the Cr concentration. Gill showed synergistic effects on LPO and GPX increase, as well as on CAT and GSH decrease for the lowest

  3. Occurrence of POPs and other persistent organic contaminants in the European eel (Anguilla anguilla) from the Loire estuary, France.

    Science.gov (United States)

    Couderc, M; Poirier, L; Zalouk-Vergnoux, A; Kamari, A; Blanchet-Letrouvé, I; Marchand, P; Vénisseau, A; Veyrand, B; Mouneyrac, C; Le Bizec, B

    2015-02-01

    The chemical contamination of the Loire estuary by three classes of persistent organic pollutants (POPs): the polychlorinated biphenyls (PCBs), the polybrominated diphenyl ethers (PBDEs) and the perfluorinated and polyfluorinated alkyl substances (PFAS), and three families of organic contaminants, the alkylphenols (APs), the polycyclic aromatic hydrocarbon metabolites (OH-PAHs) and the bisphenol A (BPA) were investigated in the muscles and bile of European eel (Anguilla anguilla). Yellow eels (n=30) were caught in three different points along the estuary to highlight variations between sites and sources of contaminations. Silver eels (n=15) were also studied to compare contaminant impregnation between different life stages of the species. Average concentrations in the muscles of the eel ranged between: 857 and 4358 ng/gLW for the PCBs, 26 and 46 ng/gLW for the PBDEs, 130 and 1293 ng/gLW for the PFAS; and in bile: 31 and 286 μg/g protein for the APs, 9 and 26 μg/g protein for the OH-PAHs and ND-1213 μg/g protein for the BPA. Among PCBs, PCB 153 (40% contribution to the sum of PCBs) was predominant in all eel muscles. PBDE 47 (60%) was the most predominant PBDE congeners, while perfluorooctanesulfonic acid (85%) was the most widely detected PFAS. For APs, 4p-nonylphenol (91%) was the most abundant and for the OH-PAHs, it was 1OH-Pyrene (63%). All the eels exceeded the environmental quality standards (EQS) for biota for the PBDEs and about 75% were higher than the EQS specific to PFOS. Finally, 20% of the analyzed eels presented TEQ concentrations above the maximum limits for lipid-rich species. These results supplied new data on the occurrence, levels, and patterns of 53 organic chemicals in the eels from the Loire estuary and they highlighted the need of further investigations focused notably on the potential effects of these chemicals on this species and their analysis in the water and sediments of the estuary.

  4. Kinematics and hydrodynamics of linear acceleration in eels, Anguilla rostrata.

    Science.gov (United States)

    Tytell, Eric D

    2004-12-22

    The kinematics and hydrodynamics of routine linear accelerations were studied in American eels, Anguilla rostrata, using high-speed video and particle image velocimetry. Eels were examined both during steady swimming at speeds from 0.6 to 1.9 body lengths (L) per second and during accelerations from -1.4 to 1.3 L s(-2). Multiple regression of the acceleration and steady swimming speed on the body kinematics suggests that eels primarily change their tail-tip velocity during acceleration. By contrast, the best predictor of steady swimming speed is body wave speed, keeping tail-tip velocity an approximately constant fraction of the swimming velocity. Thus, during steady swimming, Strouhal number does not vary with speed, remaining close to 0.32, but during acceleration, it deviates from the steady value. The kinematic changes during acceleration are indicated hydrodynamically by axial fluid momentum in the wake. During steady swimming, the wake consists of lateral jets of fluid and has minimal net axial momentum, which reflects a balance between thrust and drag. During acceleration, those jets rotate to point downstream, adding axial momentum to the fluid. The amount of added momentum correlates with the acceleration, but is greater than the necessary inertial force by 2.8+/-0.6 times, indicating a substantial acceleration reaction.

  5. Effects of exercise and temperature on geosmin excretion by European eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Schram, E.; Schrama, J.W.; Kusters, K.; Kwadijk, C.J.A.F.; Palstra, A.P.

    2016-01-01

    The presence of geosmin in fish products causes an earthy or musty off-flavour. To avoid economic damage resulting from market entrance of off-flavoured fish products, fish farmers utilize the reversibility of geosmin uptake to depurate the off-flavours from their fish crops by holding them in clean

  6. Temporal variations in embryotoxicity of Lake Ontario American eel (Anguilla rostrata) extracts to developing Fundulus heteroclitus.

    Science.gov (United States)

    Rigaud, Cyril; Couillard, Catherine M; Pellerin, Jocelyne; Légaré, Benoît; Byer, Jonathan D; Alaee, Mehran; Lebeuf, Michel; Casselman, John M; Hodson, Peter V

    2016-01-15

    The recruitment of American eel (Anguilla rostrata) juveniles to Lake Ontario (LO), Canada has declined significantly since the 1980s. To investigate the possible contribution of maternally-transferred persistent organic pollutants (POPs) to this decline, this study measured temporal variations in the toxicity of complex organic mixtures extracted from LO American eels captured in 1988, 1998 and 2008 to developing Fundulus heteroclitus exposed by intravitelline (IVi) injection. The 1988 and 1998 eel extracts were most toxic, causing a pattern of sublethal embryotoxic responses similar to those previously reported in F. heteroclitus embryos exposed to single dioxin-like compounds (DLCs): stunted growth, craniofacial deformities, EROD activity induction, and reduced predatory capacities. The potency of extracts declined over time; the only significant effect of the 2008 eel extracts was EROD induction. The chemically-derived TCDD-TEQs of eel extracts, calculated using measured concentrations of some DLCs and their relative potencies for F. heteroclitus, overestimated their potency to induce EROD activity possibly due to interactions among POPs. Other POPs measured in eel extracts (non-dioxin-like PCBs, PBDEs and organochlorinated pesticides) did not appear to be important agonistic contributors to the observed toxicity. The toxicity of the complex mixtures of POPs measured in LO eels may have been underestimated as a result of several factors, including the loss of POPs during extracts preparation and a focus only on short-term effects. Based on the model species examined, our results support the hypothesis that contamination of LO with DLCs may have represented a threat to the American eel population through ecologically-relevant effects such as altered larval prey capture ability. These results prioritize the need to assess early life stage (ELS) toxicity of DLCs in Anguilla species, to investigate long-term effects of complex eel extracts to ELS of fish, and to

  7. Impact of long-term habitat loss on the Japanese eel Anguilla japonica

    Science.gov (United States)

    Chen, Jian-Ze; Huang, Shiang-Lin; Han, Yu-San

    2014-12-01

    Since the 1970s, the loss of temperate-zone anguillid eels, particularly Anguilla anguilla, Anguilla rostrata, and Anguilla japonica, has exceeded 90% based on estimates of glass eel recruitment. The cause of this decline has not been conclusively determined, although many factors have been proposed. In East Asia, the consequences of long-term habitat loss and deterioration of habitat quality on the sustainability of Japanese eel resources are important. Impacts have already occurred and are expected to increase because hundreds of millions of people live near estuaries and rivers that have undergone, and further, are expected to continue to undergo, substantial changes in land use. Driven by economic growth, these landscape changes have resulted in, and may continue to produce, the large-scale destruction of eel habitats. We used chronological Landsat imagery to measure Japanese eel habitat reduction from human activities in 16 rivers in East Asia, including Japan, Korea, Taiwan, and China. On average, 76.8% of the effective habitat area (Ae) was lost in these 16 rivers from the 1970s-2010s. Taiwan and China had the highest percentages of Ae loss, with declines of 49.3% and 81.5%, respectively. Extensive habitat loss may play an important role, together with regional climate phenomena such as the ENSO and overfishing, in the decline of the Japanese eel in East Asia. Measures targeting habitat restoration and protection may need to be integrated into management planning for Japanese eel resources in an international rather than regional context.

  8. Locomotor activity rhythm in the Japanese eel Anguilla japonica elvers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Under artificial LD cycles (6, 12, 18 L), the elvers of Japanese eel, Anguilla japonica, showed a 24 h cycle of locomotor activity rhythm being most active at light transitions: the eels' activity rose to a primary peak after lights-off, followed by a quiescent period during which they buried into the shelters or lying motionlessly on sand for most of the time, and then reached a secondary peak before lights-on. Elvers could resynchronize their activity rhythm with a new photo cycle within 4 d. Moreover, their activity level at dark phase significantly increased as the light period was prolonged: higher activity levels during shorter dark period. However, the elvers did not display clearly the existence of a circadian rhythm under constant light or dark conditions. The timing of daily activity rhythm evidenced in the Japanese eels may occur through the action of the LD cycles with a weak participation of an endogenous circadian system. In all the LD cycles, over 99% of the activity occurred in the dark phase, indicating that the eels were always nocturnally active no matter what time of day it might be. Under 12 L conditions, the eels' activity level and the time outside sand were significantly elevated both at light and dark phases as temperature increased from 10~15 to 20~25 ℃. The activity rhythm pattern (i.e., two peaks occurring around light transitions) did not apparently change among temperatures. However, in contrast with the primary activity peaks immediately after lights-off at 20 and 25 ℃, the timing of the primary peaks at 10 and 15 ℃ showed a latency of a few hours following lights-off, indicating the inhibiting effect of low temperature on the eels' activity.

  9. Schooling reduces energy consumption in swimming male European eels, Anguilla anguilla L.

    NARCIS (Netherlands)

    Burgerhout, E.; Tudorache, C.; Brittijn, S.A.; Palstra, A.P.; Dirks, R.P.; Thillart, G.E.E.J.M.

    2013-01-01

    During migration, swimming in schools provides fish with a number of behavioural and ecological advantages, including increased food supply and reduced predation risk. Previous work shows that carangiform and tunniform swimming result in energetic advantages for individuals using a diamond swimming

  10. Schooling reduces energy consumption in swimming male European eels, Anguilla anguilla L.

    NARCIS (Netherlands)

    Burgerhout, E.; Tudorache, C.; Brittijn, S.A.; Palstra, A.P.; Dirks, R.P.; Thillart, G.E.E.J.M.

    2013-01-01

    During migration, swimming in schools provides fish with a number of behavioural and ecological advantages, including increased food supply and reduced predation risk. Previous work shows that carangiform and tunniform swimming result in energetic advantages for individuals using a diamond swimming

  11. PEMANFAATAN LIMBAH IKAN SIDAT INDONESIA (Anguilla bicolor SEBAGAI TEPUNG PADA INDUSTRI PENGOLAHAN IKAN DI PALABUHANRATU, KABUPATEN SUKABUMI

    Directory of Open Access Journals (Sweden)

    RA Hangesti Emi Widyasari

    2014-05-01

    Full Text Available ABSTRACTThis research aims to analyze the nutritive value of flour head, liver powder and bone meal as by product of Indonesian eel (Anguilla bicolor processing. Eel waste flour was made by using a thermal process in the drum dryer fish flouring mill PT. Carmelitha Lestari in Bogor, whereas proximate analysis for chemical tests were performed in the laboratory of Integrated Chemical Laboratory, IPB and direct observation was conducted in PT Jawa Suisan Indah, Palabuhanratu Sukabumi district in October 2012—April 2013. The nutritive value based on proximate analysis showed that head flour, liver flour, and bone flour contained protein 61.78%, 53.92%, and 41.01%; fat 15.55%, 27.28%, 13.07%; carbohydrate 11.48%; 14.96%, 8.13%; water 5.44%, 8.48%, 3.01%; ash 12.95%, 3.62%, 37.49%, and crude fiber 1.33%, 0.04%, 1.11%, respectively.Keywords: Anguilla bicolor, bone flour, head flour, liver flour, nutritive valueABSTRAKPenelitian ini bertujuan untuk menganalisis kandungan gizi tepung kepala, tepung tulang dan tepung hati ikan yang merupakan limbah pengolahan ikan sidat Indonesia (Anguilla bicolor. Tepung limbah ikan sidat dibuat berdasarkan proses termal menggunakan drum dryer di pabrik penepungan ikan PT. Carmelitha Lestari di Bogor dan analisis proksimat untuk uji kimiawi dilakukan di Laboratorium Kimia Terpadu, IPB serta observasi langsung di PT Jawa Suisan Indah, Palabuhanratu Kabupaten Sukabumi pada bulan Oktober 2012—April 2013. Hasil analisis proksimat tepung kepala, tepung hati dan tepung tulang mengandung protein berturut-turut sebesar 61.78%, 53.92%, dan 41.01%; lemak sebesar 15.55%; 27.28%; 13.07%, karbohidrat sebesar 11.48%; 14.96%; 8.13%, kadar air sebesar 5.44%; 8.48%; 3.01%, kadar abu 12.95%; 3.62%; 37.49% dan serat kasar 1.33%; 0.04%; 1.11%.Kata kunci: Anguilla bicolor, nilai gizi, tepung hati, tepung kepala, tepung tulang

  12. Temporal and spatial changes in the composition and structure of helminth component communities in European eels Anguilla anguilla in an Adriatic coastal lagoon and some freshwaters in Italy.

    Science.gov (United States)

    Dezfuli, Bahram Sayyaf; Giari, Luisa; Castaldelli, Giuseppe; Lanzoni, Mattia; Rossi, Remigio; Lorenzoni, Massimo; Kennedy, Clive Russell

    2014-01-01

    The composition and diversity of the helminth component communities in eels Anguilla anguilla were determined in three separate localities in Italy: an Adriatic coastal lagoon, Comacchio and two freshwater localities, the River Po and the Lake Piediluco. Data from Comacchio lagoon were analysed over 15 years to determine whether community composition and diversity changed significantly overtime. The community was species rich (nine species, all marine except Proteocephalus macrocephalus) and was dominated by a suite of digeneans: Deropristis inflata, Helicometra fasciata, Lecithochirium musculus and Bucephalus anguillae. The community showed little change in composition over the period, but the relative abundance and dominance of the species did alter. By contrast, the component communities in the freshwater localities were species poor and the dominant species were freshwater acanthocephalans, Pomphorhyncus laevis in River Po and Acanthocephalus rhinensis in Lake Piediluco. The helminth community of Lake Piediluco with five species was richer than that of the River Po with only three species, but was poorer than that of Comacchio lagoons. Similarity indices between samples from Comacchio were high; between the lagoon and the freshwater localities and between the two freshwater localities, similarity indices were very low. Helminth component community structure in coastal lagoons was comparable across Europe. The helminth community in the River Po was similar to those in the River Tiber and other European rivers whilst that in Lake Piediluco was similar to that in other European lakes. Levels of the pathogenic Anguillicoloides crassus in swim bladders were consistently lower in prevalence and abundance in the coastal lagoons than in freshwater localities. This suggests that this parasite may have little impact on migrating eels if they are indeed primarily of marine origin and so it may be of little importance in the recent decline of eel populations throughout

  13. PROTOZOA PARASITIK PADA IKAN SIDAT (ANGUILLA SPP.) ASAL DANAU LINDU, SULAWESI TENGAH

    OpenAIRE

    Arif Rahman Jabal; Umi Cahyaningsih; Risa Tiuria

    2015-01-01

    Infection protozoan parasitic on eels (Anguilla spp.) from Lindu Lake was affected weight eels and health eels. The protozoan parasitic examinations were collection of eels, inspection eels, observation, measurement, identification of parasites, and staining protozoan used giemsa stained, trematode used semichons’s acetocarmine stained and nematode used clove oil and KOH. The diversity of parasitic protozoan found such as: Myxidium sp., Myxobolus sp., Chilodonella sp., Ceratomyxa sp., Balanti...

  14. Uptake and elimination of cadmium by Japanese Eel, Anguilla japonica, at various temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Yang, H.N.; Chen, H.C. [National Taiwan Univ. (China)

    1996-04-01

    There is no evidence that cadmium is biologically essential, but its toxicity to organisms is well known. The so-called Itai-Itai disease in Japan, characterized by osteomalacia and renal tubular malfunction, has been attributed to cadmium poisoning in irrigation water. The degree of contamination in aquatic environments is frequently assessed by comparing contaminant concentrations in associated biota. Bioaccumulation, however, is influenced by environmental factors other than the degree of contamination, environmental factors such as salinity, temperature and pH. The use of cadmium in the electroplating industry in Taiwan is intensive, but the wastewater used in this industry is seldom treated and has been a serious problem. The Japanese eel (Anguilla japonica) is an important freshwater aquacultural fish in Taiwan; thus, it is important to know the accumulation and elimination of cadmium in the Japanese eel due to cadmium-polluted water at various temperatures in order to protect eel resources as well as human health. 18 refs., 3 figs., 1 tab.

  15. Ubiquitous distribution of fluorescent protein in muscles of four species and two subspecies of eel (genus Anguilla)

    Indian Academy of Sciences (India)

    AKI FUNAHASHI; TAKAO ITAKURA; ABEER A. I. HASSANIN; MASAHARU KOMATSU; SEIICHI HAYASHI; YOSHIO KAMINISHI

    2017-03-01

    In this study, the localization of fluorescent protein (FP) was characterized in the muscles of four species and two subspecies of eels Anguilla anguilla, A. australis, A. bicolor bicolor (b.), A. bicolor pacifica (p.) and A. mossambica in addition tothe previously reported A. japonica. The open reading frame of each eel FP was 417 bp encoding 139 amino acid residues. The deduced amino acid sequences among the four species and two subspecies exhibited 91.4–100% identity, and belonged to the fatty-acid-binding protein (FABP) family. The gene structure of eel FPs in A. japonica, A. anguilla, A. australis, A. bicolor b., A. bicolor p. and A. mossambica have four exons and three introns, and were common to that of FABP family. The apo eel FPs expressed by Escherichia coli with recombinant eel FP genes were analysed for the fluorescent properties in the presenceof bilirubin. The excitation and emission spectra of holo eel FPs had the maximum wavelengths of 490–496 and 527–530 nm, respectively. The holo eel FPs indicated that the fluorescent intensities were stronger in A. japonica and A. bicolor than in A. mossambica, A. australis and A. anguilla. The comparison of amino acid sequences revealed two common substitutions in A.mossambica, A. australis and A. anguilla with weak fluorescent intensity.

  16. Assessment of persistent brominated and chlorinated organic contaminants in the European eel (Anguilla anguilla) in Flanders, Belgium: Levels, profiles and health risk.

    Science.gov (United States)

    Malarvannan, Govindan; Belpaire, Claude; Geeraerts, Caroline; Eulaers, Igor; Neels, Hugo; Covaci, Adrian

    2014-06-01

    Pooled yellow European eel (Anguilla anguilla (L.)) samples, consisting of 3-10 eels, collected between 2000 and 2009 from 60 locations in Flanders (Belgium) were investigated for persistent contaminants, such as polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane and its metabolites (DDTs). The current study expands the knowledge regarding these contaminant concentrations, their patterns and distribution profiles in aquatic ecosystems. PBDEs, HBCDs, PCBs, and DDTs were detected in all eel samples and some samples had high concentrations (up to 1400, 9500, 41,600 and 7000ng/g lw, respectively). PCB levels accounted for the majority of the contamination in most samples. The high variability in PBDE, HBCD, PCB and DDT concentrations reported here is likely due to the variety in sampling locations demonstrating variable local pollution pressures, from highly industrialised areas to small rural creeks. Among PBDEs, BDE-47 (57% contribution to the sum PBDEs), -100 (19%) and -99 (15%) were the predominant congeners, similar to the composition reported in the literature in eel samples. For HBCDs, α-HBCD (74%) was predominant followed by γ-(22%) and β-HBCD (4%) isomers in almost all eel samples. CB-153 (19%) was the most dominant PCB congener, closely followed by CB-138 (11%), CB-180 (9%), CB-187 (8%) and CB-149 (7%). The contribution to the total human exposure through local wild eel consumption was also highly variable. Intake of PBDEs and HBCDs, through consumption of wild eel, was below the RfD values for the average population (consuming on average 2.9g eel/day). At 16 out 60 sites, eels exceeded largely the new EU consumption threshold for PCBs (300ng/g ww for the sum of 6 indicator PCBs). The current data shows an on-going exposure of Flemish eels to PBDEs, HBCDs, PCBs and DDTs through indirect release from contaminated sediments or direct releases from various industries.

  17. PROTOZOA PARASITIK PADA IKAN SIDAT (ANGUILLA SPP. ASAL DANAU LINDU, SULAWESI TENGAH

    Directory of Open Access Journals (Sweden)

    Arif Rahman Jabal

    2015-08-01

    Full Text Available Infection protozoan parasitic on eels (Anguilla spp. from Lindu Lake was affected weight eels and health eels. The protozoan parasitic examinations were collection of eels, inspection eels, observation, measurement, identification of parasites, and staining protozoan used giemsa stained, trematode used semichons’s acetocarmine stained and nematode used clove oil and KOH. The diversity of parasitic protozoan found such as: Myxidium sp., Myxobolus sp., Chilodonella sp., Ceratomyxa sp., Balantidium sp., Henneguya sp., and Glugea sp. The highest prevalence Myxidium sp. in eels was 77% and no protozoan dominated between other parasites. Based on chi-square test, protozoan parasitic had a different preference to organs of eels.

  18. The giant mottled eel, Anguilla marmorata, uses blue-shifted rod photoreceptors during upstream migration.

    Directory of Open Access Journals (Sweden)

    Feng-Yu Wang

    Full Text Available Catadromous fishes migrate between ocean and freshwater during particular phases of their life cycle. The dramatic environmental changes shape their physiological features, e.g. visual sensitivity, olfactory ability, and salinity tolerance. Anguilla marmorata, a catadromous eel, migrates upstream on dark nights, following the lunar cycle. Such behavior may be correlated with ontogenetic changes in sensory systems. Therefore, this study was designed to identify changes in spectral sensitivity and opsin gene expression of A. marmorata during upstream migration. Microspectrophotometry analysis revealed that the tropical eel possesses a duplex retina with rod and cone photoreceptors. The λmax of rod cells are 493, 489, and 489 nm in glass, yellow, and wild eels, while those of cone cells are 508, and 517 nm in yellow, and wild eels, respectively. Unlike European and American eels, Asian eels exhibited a blue-shifted pattern of rod photoreceptors during upstream migration. Quantitative gene expression analyses of four cloned opsin genes (Rh1f, Rh1d, Rh2, and SWS2 revealed that Rh1f expression is dominant at all three stages, while Rh1d is expressed only in older yellow eel. Furthermore, sequence comparison and protein modeling studies implied that a blue shift in Rh1d opsin may be induced by two known (N83, S292 and four putative (S124, V189, V286, I290 tuning sites adjacent to the retinal binding sites. Finally, expression of blue-shifted Rh1d opsin resulted in a spectral shift in rod photoreceptors. Our observations indicate that the giant mottled eel is color-blind, and its blue-shifted scotopic vision may influence its upstream migration behavior and habitat choice.

  19. Solvent and extraction methods effects on the quality of eel (Anguilla bicolor) oil

    Science.gov (United States)

    Sasongko, H.; Efendi, N. R.; Budihardjo, A.; Farida, Y.; Amartiwi, T.; Rahmawati, A. A.; Wicaksono, A.; Sugiyarto

    2017-01-01

    Eel (Anguilla bicolor) is a general fish consumption in many countries, especially Japan, China, Germany, and France. Besides its vitamin rich, eel oil is also known to contain fatty acids that are necessary for pharmaceutical purposes and as food a supplement. This research was aimed to evaluate the quality of eel oil by different solvent and extraction methods. In this study, fresh eels were extracted using maceration and reflux methods.Chloroform was used as the solvent in the maceration while water used in the reflux method. The oil quality was examined based on the Official Methods of Analysis of the Association of Official Analytical Chemist (AOAC).The result showed that the yield of eel oil using maceration method was 5.44% ± 0.64 with a specific gravity of 0.915 g/mL, while reflux method obtained the yield of 5.33 % ± 0.84 and specific gravity of 0.8575 g/mL. The physicochemical parameters of oil quality used in this study were acid, peroxide, saponification, and iodine value. The maceration method obtained the acid value of 17.389 mgKOH/g, the peroxide value of 7.021meqO2/kg, the saponification value of 111.16mgKOH/g, and the iodine value of 65.14 WIJS. While the reflux method produced the acid value of 9.116 mgKOH/g, the peroxide value of 6.088 meqO2/kg, the saponification value of 70 mgKOH/g, and the iodine value of 87.74 WIJS.

  20. EVIDENCE SUPPORTING THE OCCURRENCE AND THE ECOLOGICAL IMPLICATION OF GIANT MOTTLED EEL, ANGUILLA MARMORATA (ACTINOPTERYGII: ANGUILLIFORMES: ANGUILLIDAE), FROM SABAH, BORNEO ISLAND

    National Research Council Canada - National Science Library

    Li Lian Wong; Siti Raudah Abdul Kadir; Rabi Atun Adawiah Abdullah; Charlie Albert Lasuin; Kok Onn Kwong; Takaomi Arai

    2017-01-01

    .... Two anguillid eels found in Sabah, Borneo Island, were firstly identified as Anguilla marmorata Quoy et Gaimard, 1824 using morphological analysis and further analysis of mitochondrial 16S ribosomal RNA (16S rRNA...

  1. EVIDENCE SUPPORTING THE OCCURRENCE AND THE ECOLOGICAL IMPLICATION OF GIANT MOTTLED EEL, ANGUILLA MARMORATA (ACTINOPTERYGII: ANGUILLIFORMES: ANGUILLIDAE), FROM SABAH, BORNEO ISLAND

    National Research Council Canada - National Science Library

    Li Lian Wong; Siti Raudah Abdul Kadir; Rabi Atun Adawiah Abdullah; Charlie Albert Lasuin; Kok Onn Kwong; Takaomi Arai

    2017-01-01

      Although tropical anguillid eels account for two-thirds of all species in the genus Anguilla, the information on the species diversity, geographic distribution, and life histories of the tropical eels is very limited...

  2. RECRUTEMENT DES CIVELLES (ANGUILLA ANGUILLA SUR LA COTE MEDITERRANEENNE FRANÇAISE : ANALYSE COMPAREE DES CARACTERISTIQUES BIOMETRIQUES ET PIGMENTAIRES DES SAISONS 1974-75 ET 2000-01.

    Directory of Open Access Journals (Sweden)

    LEFEBVRE F.

    2003-07-01

    Full Text Available Une campagne d’échantillonnage des civelles Anguilla anguilla a été menée de novembre 2000 à mai 2001 au grau de la Fourcade (Saintes-Maries-de-la-Mer, côte méditerranéenne française. Des civelles ont été capturées sur toute la période d’échantillonnage, mais les maxima d’abondance se situent en janvier-février et, dans une moindre mesure, en avril. Afin d’optimiser le recrutement dans les lagunes littorales intérieures, la mesure de gestion proposée est donc de favoriser l’ouverture des martelières au milieu de l’hiver. Le suivi des proportions mensuelles des différents stades pigmentaires (de V A à VI A4 permet de conclure à un vieillissement généralisé des civelles en recrutement de novembre à mars, puis à l’arrivée d’un deuxième flux de civelles jeunes en avril. Parallèlement, il est observé une diminution très nette des masses et des longueurs moyennes mensuelles, et ce, même en ne considérant qu’un stade pigmentaire donné (en l’occurrence V B. Ces résultats sur l’évolution des caractéristiques biométriques et pigmentaires sont en accord avec les deux séries de travaux déjà menés sur la façade méditerranéenne française (années 30 et 70, ainsi qu’avec les données publiées en différents points de la façade atlantique. L’analyse comparée de ces données avec celles issues de la dernière étude en date sur la côte méditerranéenne française (Bages-Sigean, Languedoc-Roussillon, campagne 1974-75 ; LECOMTE-FINIGER, 1976 montre une composition pigmentaire mensuelle totalement différente, et révèle une diminution significative de la longueur des civelles, de l’ordre de 5 % en 25 ans.

  3. 欧洲鳗鲡肝肾病病原菌的分离与鉴定%Isolation and Identification of Bacteriosis Pathogen from Anguilla anguilla with Edwardsiellasis

    Institute of Scientific and Technical Information of China (English)

    吴斌; 樊海平; 曾占壮; 张新艳; 王凡

    2010-01-01

    患肝肾病的养殖欧洲鳗鲡(Anguilla anguilla)出现肝、肾肿大,且肝脏具白色溃疡灶的症状.从肝脏中分离、纯化到优势细菌,定名AL60306NA1.人工感染试验证实:向欧洲鳗鲡腹腔内注射1.0×108 cfu/mL菌株悬液,实验鱼死亡率达100.0%;注射1.0×107 cfu/mL,死亡率为60.0%;形态学观察、API 20E细菌鉴定试剂盒鉴定实验证明菌株AL60306NA1有动力、拥有革兰氏反应阴性、氧化酶阴性、H2O2酶阳性、兼性厌氧、发酵葡萄糖产酸产气、不发酵蔗糖和蜜二糖及L-阿拉伯糖、赖氨酸脱羧酶阳性、柠檬酸盐弱阳性、产生硫化氢和吲哚、MR阳性和典型的β-溶血等特征;16S rRNA特异性基因分析鉴定实验说明克隆的AL60306NA1 16S rRNA基因部份序列为1507bp、与迟缓爱德华氏菌(AB050829.1)的同源性达99.7%.综合上述结果,确定该菌株为养殖欧洲鳗鲡肝肾病的病原菌,并鉴定为迟缓爱德华氏菌(Edwardsiella tarda)野生型.用菌株AL60306NA1感染小白鼠实验测定该菌对小白鼠的LD50为7.1×105 cfu/mL,同时自该菌株PCR扩增到长度约1 000 bp的溶血素基因特异性片段,结果表明菌株AL60306NA1有一定的致病力.

  4. Donor life stage influences juvenile American eel Anguilla rostrata attraction to conspecific chemical cues

    Science.gov (United States)

    Galbraith, Heather S.; Blakeslee, Carrie J.; Schmucker, Andrew K.; Johnson, Nicholas; Hansen, Michael J.; Li, Weiming

    2017-01-01

    The present study investigated the potential role of conspecific chemical cues in inland juvenile American eel Anguilla rostrata migrations by assessing glass eel and 1 year old elver affinities to elver washings, and elver affinity to adult yellow eel washings. In two-choice maze assays, glass eels were attracted to elver washings, but elvers were neither attracted to nor repulsed by multiple concentrations of elver washings or to yellow eel washings. These results suggest that A. rostrata responses to chemical cues may be life-stage dependent and that glass eels moving inland may use the odour of the previous year class as information to guide migration. The role of chemical cues and olfaction in eel migrations warrants further investigation as a potential restoration tool.

  5. Behaviour and passage of European silver eels (Anguilla anguilla at a small hydropower plant during their downstream migration Comportement et passage de l’anguille argentée (Anguilla anguilla au niveau d’une petite centrale hydroélectrique lors de sa migration de dévalaison

    Directory of Open Access Journals (Sweden)

    De-Oliveira E.

    2010-09-01

    Full Text Available Between 2004 and 2007, 116 downstream migrant silver eels (Anguilla anguilla were monitored at a hydropower plant on the Gave de Pau river in South-West France using radio and PIT telemetry. The objectives of the study were: (i to determine the environmental conditions when eels arrived and passed the facility; (ii to determine the rate of eel escapement (passage other than via the turbines; (iii to describe the behaviour of eels faced with the intake structure and the permeability of the intake trashracks for the different sizes of eel; and (iv to determine whether surface bypasses originally designed for salmon could be effective for eels. Five types of behaviour of silver eels in the forebay and at the plant intakes were identified. The study showed the key factor influencing both eel behaviour and the route taken through the plant was variation in river discharge. Escapement rate was related to eel length and the spill flow to river flow ratio, which could be described by a logistic regression model. The surface bypasses originally designed for salmon were found to aid downstream eel migration significantly. At velocities < 0.40 m·s−1, no eels, even the largest, for which the racks are a physical barrier, were found impinged on the trashracks. De 2004 à 2007, une étude sur la migration de dévalaison de l’anguille argentée européenne (Anguilla anguilla a été menée sur la centrale hydroélectrique de Baigts sur le Gave de Pau dans le Sud-Ouest de la France. Cette étude, au cours de laquelle 116 individus ont été suivis par télémétrie PIT et radio, avait pour objectifs : (i de déterminer les conditions de milieu propices à l’arrivée sur site et au franchissement de l’aménagement; (ii de déterminer les taux d’échappement (passages par des voies autres que les turbines; (iii d’analyser le comportement des anguilles devant les ouvrages et la perméabilité des grilles de la prise d’eau en fonction de la taille

  6. A quick method for species identification of Japanese eel (Anguilla japonica) using real-time PCR: an onboard application for use during sampling surveys.

    Science.gov (United States)

    Watanabe, Shun; Minegishi, Yuki; Yoshinaga, Tatsuki; Aoyama, Jun; Tsukamoto, Katsumi

    2004-01-01

    To compensate for the limited number of morphological characteristics of fish eggs and larvae, we established a convenient and robust method of species identification for eggs of the Japanese eel (Anguilla japonica) using a real-time polymerase chain reaction (PCR) that can be performed onboard research ships at sea. A total of about 1.2 kbp of the mitochondrial 16S ribosomal RNA gene sequences from all species of Anguilla and 3 other anguilliform species were compared to design specific primer pairs and a probe for A. japonica. This real-time PCR amplification was conducted for a total of 44 specimens including A. japonica, A. marmorata, A. bicolor pacifica, and 6 other anguilliform species. Immediate PCR amplification was only observed in A. japonica. We then tested this method under onboard conditions and obtained the same result as had been produced in the laboratory. These results suggest that real-time PCR can be a powerful tool for detecting Japanese eel eggs and newly hatched larvae immediately after onboard sampling during research cruises and will allow targeted sampling efforts to occur rapidly in response to any positive onboard identification of the eggs and larvae of this species.

  7. Movement patterns of seaward migrating European eel (Anguilla anguilla) at a complex of riverine barriers: implications for conservation

    DEFF Research Database (Denmark)

    Piper, Adam T.; Svendsen, Jon Christian; Wright, Rosalind M.;

    2017-01-01

    River infrastructure such as weirs and hydropower stations commonly present migrating fish with multiple potential passage routes. Knowledge of the cues fish use to navigate such environments is required to protect migrants from hazardous areas and guide them towards safe passage; however...

  8. Gastrointestinal and metabolic effects of feeding schedule on voluntary feed intake and growth of European eel, Anguilla anguilla

    NARCIS (Netherlands)

    Heinsbroek, L.T.N.; Goedegebuur, B.J.; Bloemhof, G.; Flach, R.B.; Jong, de G.D.C.

    2008-01-01

    Gastrointestinal and metabolic influences on short- and medium-term control of voluntary feed intake of European eel were investigated for groups of fish fed at different feeding schedules: 1 meal 2 days(-1), 1 meal day(-1), 2 meals day(-1) and continuous feeding for 12 h and 24 h daily. For fish fe

  9. Trichodina sp. ( Ciliophora: Peritrichida ) in eel Anguilla anguilla in recirculation systems in Denmark : host-parasite relations

    DEFF Research Database (Denmark)

    Madsen, H.C.K.; Buchmann, Kurt; Mellergaard, Stig

    2000-01-01

    Farmed eel cultured in recirculation systems in Denmark were found infected by Trichodina jadranica Raabe, 1958. Associations between parasite abundance and fish size was examined in 2 different production systems. In one system, stocked with relatively well-nourished eels (3 to 31 g), most...... of the parasites (66%) were found on the dorsal part on the skin and relatively few were found on the gills (approx. 8%). The infection level was significantly positively correlated both with fish weight and length. In the other system, stocked with relatively malnourished small eels (0.5 to 4 g), significantly...

  10. Kinetics of radiolabelled silver uptake and depuration in the gills of rainbow trout (Oncorhynchus mykiss) and European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Wood, C.M.; Grosell, M.; Hogstrand, C.;

    2002-01-01

    chloride is known to protect against physiological disturbances and toxicity caused by Ag+. In both fish species, at both chloride levels, silver uptake exhibited complex kinetics. Gill silver loading occurred slowly until 6 h, then rose greatly to a peak at 12 h, followed by significant net depuration...

  11. The dynamics of the nematode Anguillicola crassus, Kuvahara 1974 in eel Anguilla anguilla (L. 1758) in the Sebou estuary (Morocco).

    Science.gov (United States)

    Loukili, Abdechahid; Belghyti, Driss

    2007-03-01

    The European eel is a vulnerable fish by its complex life cycle, by the impact of pollution of the near total of freshwater aquatic environments, and by the gravity and the diversity of its parasites (nematodes, cestodes, trematodes, the Copepoda, Coccidia...). It is classified in the red book of threatened species. The anguillulose is the principal parasitic pathology of an eel either in the natural environment or in the aquaculture. The eels taken in the three zones of the Sebou estuary of varied environmental conditions were dissected for the research of parasites. Of the fish, 85.7% are infested upstream of the estuary, whereas only 71% shelter this parasite in their swim bladder, with an abundance of 2.09 per fish downstream and 83.8 in zone 2. The present study suggests the development stage of the fish, and therefore its diet, has an influence on the parasitic infestation. The estuaries and the lagoons constitute a very significant medium for the safeguarding and the disinfection of parasitized eels.

  12. Pengaruh pemberian pakan berupa campuran pelet ikan, ulat tepung (Tenebrio molitor, dan ganggang merah (Gracilaria foliifera terhadap pertumbuhan dan kelulushidupan ikan sidat (Anguilla bicolor

    Directory of Open Access Journals (Sweden)

    MUHAMMAD A. AZIZ HENDITAMA

    2015-05-01

    Full Text Available Henditama MAA, Harini M, Budiharjo A. 2015. The effect of giving mixtured feed of fish pellet, mealworm (Tenebrio molitor and red algae (Gracilaria foliifera to the growth and survival rate of eel (Anguilla bicolor. Bioteknologi 12: 22-28. High demand of eels (Anguilla bicolor in the world has not followed by the capability of domestic production. The purpose of this research are to determine the effect and the precise composition of the feed mixture in the form of fish pellets, mealworms (Tenebrio molitor, red algae (Gracilaria foliifera to the growth and survival rate of eels. This research used completely randomized design with four variations of mixtured feed in the form of fish pellet, mealworms, and red algae specifically P1 (100% ; 0% ; 0%, P2 (75% ; 20% ; 5%, P3 (50% ; 45% ; 5%, P4 (25% ; 70% ; 5%. This research also has been done in 90 days with feeding in twice a day. The data of growth, survival rate, and water quality was collected once a week. The data result has been analized by ANOVA. The data result showed that have a real different to continue to the next analysis of DMRT with test level 5% to locate the differences between treatments. The eels growth after feeding a mixture feed in the form of fish pellets, mealworms, and red alga, specifically: P1 (K 26.3167 gram; P2 20.3167 gram; P3 28.2500 gram; and P4 22.0000 gram. The eels survival rate, specifically P1 (K 26.67%; P2 33.33%; P3 30%; dan P4 26.67%. Furthemore, the exact composition that give the best effect of growth and survival rate to eels is 50% fish pellets, 45% mealworms and 5% red alga.

  13. Effects of salinity and sea salt type on egg activation, fertilization, buoyancy and early embryology of European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Sørensen, Sune Riis; Butts, Ian; Munk, Peter;

    2016-01-01

    sizes, while the remaining four salt types resulted in smaller eggs. All salt types except NaCl treatments led to high fertilization rates and had no effect on fertilization success as well as egg neutral buoyancies at 7 h post-fertilization. The study points to the importance of considering ionic...... composition of the media when rearing fish eggs and further studies are encouraged...

  14. Expression and localization of aquaporin 1b during oocyte development in the Japanese eel (Anguilla japonica

    Directory of Open Access Journals (Sweden)

    Matsubara Hajime

    2011-05-01

    Full Text Available Abstract To elucidate the molecular mechanisms underling hydration during oocyte maturation, we characterized the structure of Japanese eel (Anguilla japonica novel-water selective aquaporin 1 (AQP1b that thought to be involved in oocyte hydration. The aqp1b cDNA encodes a 263 amino acid protein that includes the six potential transmembrane domains and two Asn-Pro-Ala motifs. Reverse transcription-polymerase chain reaction showed transcription of Japanese eel aqp1b in ovary and testis but not in the other tissues. In situ hybridization studies with the eel aqp1b cRNA probe revealed intense eel aqp1b signal in the oocytes at the perinucleolus stage and the signals became faint during the process of oocyte development. Light microscopic immunocytochemical analysis of ovary revealed that the Japanese eel AQP1b was expressed in the cytoplasm around the yolk globules which were located in the peripheral region of oocytes during the primary yolk globule stage; thereafter, the immunoreactivity was observed throughout the cytoplasm of oocyte as vitellogenesis progressed. The immunoreactivity became localized around the large membrane-limited yolk masses which were formed by the fusion of yolk globules during the oocyte maturation phase. These results together indicate that AQP1b, which is synthesized in the oocyte during the process of oocyte growth, is essential for mediating water uptake into eel oocytes.

  15. STATUS KESEHATAN IKAN SIDAT (Anguilla sp. PADA PERAIRAN UMUM DAN WADAH PEMELIHARAAN SEMENTARA

    Directory of Open Access Journals (Sweden)

    Agung Cahyo Setyawan

    2015-03-01

    Full Text Available Status kesehatan ikan sidat (Anguilla sp. telah dianalisis untuk menunjukkan terjadinya penurunan stok karena infeksi patogen dan penangkapan benih berlebihan untuk budidaya. Di Indonesia, ketiadaan standar penangkapan, pemeliharaan dan budidaya menyebabkan terjadinya penurunan kualitas dan kuantitas produksi ikan sidat. Penelitian ini dilakukan untuk mengevaluasi status kesehatan ikan sidat di perairan Indonesia dengan sampel dari Kabupaten Banyumas dan Cilacap, Jawa Tengah. Sampling dilakukan pada awal musim penghujan, yaitu bulan September hingga November 2012. Sebanyak 113 ekor ikan sidat ditangkap dan dianalisis dalam penelitian ini, dengan perincian 57 ekor diamati langsung setelah ditangkap dan 56 ekor diamati setelah dipelihara selama 10 hari oleh pengepul. Pengamatan dilakukan dengan metode observasi langsung menggunakan mikroskop untuk parasit, kit API 20NE (Biomeureux® untuk bakteri dan pewarnaan standar haematoxylin-eosin untuk histopatologi. Terdapat empat jenis parasit (Nematoda: Camallanidae dan Anguillicoloides; Platyhelminthes: Monogenea dan Digenea dan lima bakteri (Aeromonas hydrophylla, Pseudomonas luteola, Vibrio fluvialis, Aeromonas sobria, dan Aeromonas caviae dari sampel ikan sidat dalam penelitian ini. Tidak terdapat perbedaan dalam komposisi patogen, namun terjadi perubahan dalam kondisi histopatologi sehingga pemeliharaan sementara oleh pengepul sebelum ikan sidat dibudidayakan memiliki potensi menurunkan kualitas benih untuk budidaya.

  16. Molecular characterization of Aeromonas species isolated from farmed eels (Anguilla japonica).

    Science.gov (United States)

    Yi, Seung-Won; You, Myung-Jo; Cho, Ho-Seong; Lee, Chang-Seop; Kwon, Joong-Ki; Shin, Gee-Wook

    2013-05-31

    Seventy Aeromonas strains were identified by phylogenetic analysis using housekeeping genes (gyrB and rpoD) in order to investigate etiological agents for aeromoniasis in farmed eels (Anguilla japonica). The phylogenetic analysis showed that Aeromonas aquariorum (n=22, 31.4%) was the predominant species among the investigated eel strains, followed by Aeromonas caviae (n=16, 22.9%), A. veronii (n=13, 18.6%), A. hydrophila (n=12, 17.1%), A. jandaei (n=4, 5.7%), A. media (n=2, 2.9%), and A. trota (n=1, 1.4%). The potential virulence of the present strains was estimated by performing PCR assays using the following seven virulence genes: cytotoxic enterotoxin (act), two cytotonic enterotoxins (alt and ast), glycerophospholipid:cholesterol acyltransferase (gcaT), DNase (exu), lipase (lip), and flagellin (fla). The detection rates of act, alt, ast, gcaT, exu, lip, and fla among all 70 strains were 91.4%, 55.7%, 27.1%, 97.1%, 95.7%, 100%, and 98.6%, respectively. In genotyping of enterotoxin genes, act(+)/alt(+)/ast(+), act(+)/alt(+)/ast(-), and act(+)/alt(-)/ast(-) genotypes were prevalent in A. hydrophila (8/12 strains), A. aquariorum (13/22 strains), and A. caviae (14/16 strains), respectively, suggesting a high heterogeneity among Aeromonas species. In this study, A. aquariorum, which has been an unrecorded species in Korea, can be an etiological agent for aeromoniasis of eel.

  17. Synthèse des concepts de modélisation du phénomène de migration des civelles d'Anguilla anguilla (L., 1758 en estuaire

    Directory of Open Access Journals (Sweden)

    LAMBERT P.

    1994-10-01

    Full Text Available Nous avons réalisé une synthèse bibliographique des différents modèles de migration des civelles d'anguille (Anguilla anguilla L. en estuaire. Leur confrontation montre une convergence dans le choix des facteurs du modèle (température, débit, coefficient de marée. Par contre, des différences existent dans les types de relations (linéaires ou logistiques qui lient ces paramètres aux captures par unité d'effort (CPUE journalières issues de la pêcherie professionnelle. La modélisation du patron de migration n'est pas unique dans les différents modèles. Une réflexion sur la variabilité et sur la signification des CPUE semble indispensable pour améliorer la fiabilité des modèles. Des lacunes, en particulier la prise en compte de la variabilité des caractéristiques individuelles des civelles, sont constatées.

  18. Is humane slaughter of fish possible for industry?

    NARCIS (Netherlands)

    Vis, van de J.W.; Kestin, S.; Robb, D.; Oehlenschlaeger, J.; Lambooij, E.; Kuhlmann, H.; Kloosterboer, K.

    2003-01-01

    The objective was to evaluate industrial and research slaughter methods for Atlantic salmon (Salmo salar), gilt-head seabream (Sparus auratus) and eel (Anguilla anguilla) with respect to welfare and quality. As a general term of reference, an optimal slaughter method should render fish unconscious u

  19. Migration des civelles d'anguilles (Anguilla anguilla L. dans les estuaires, modalités du phénomène et caractéristiques des individus

    Directory of Open Access Journals (Sweden)

    ELIE P.

    1994-10-01

    Full Text Available Nous avons réalisé une analyse de la littérature consacrée à la migration estuarienne de la civelle d'anguille (Anguilla anguilla L. et nous l'avons confrontée à des chroniques de données originales (abondance, structure en poids et en stades pigmentaires issues de l'estuaire de la Gironde. Ceci nous a permis de dégager la façon dont se déroule la migration. Il en ressort que les modalités du déroulement de la migration sont bien connues et relativement stables d'une année à l'autre, mais nous en sommes encore réduits à des hypothèses en ce qui concerne l'explication de son allure générale et de sa variabilité interannuelle. L'analyse des caractéristiques des individus montre une haute régularité interannuelle, on peut même parler d'un patron standard de l'évolution des individus en migration. L'action des principaux facteurs environnementaux sur les individus en migration apparaît assez nette, même si nous ne sommes pas en mesure actuellement de hiérarchiser leurs effets sur des flux migrants. Ce travail met en évidence la nécessité, pour appréhender les phénomènes migratoires et à plus forte raison pour établir un prémodèle de migration, de tenir compte de l'ensemble des aspects de la migration (tendance, facteurs modulateurs, épiphénomènes et caractéristiques des individus e n migration et d'utiliser des horloges écologiques adaptées.

  20. Tidal-Flat Macrobenthos as Diets of the Japanese Eel Anguilla japonica in Western Japan, with a Note on the Occurrence of a Parasitic Nematode Heliconema anguillae in Eel Stomachs.

    Science.gov (United States)

    Kan, Kotaro; Sato, Masanori; Nagasawa, Kazuya

    2016-02-01

    Dietary items of the Japanese eel Anguilla japonica inhabiting estuaries were examined by analyses of the gut (stomach and intestine) contents in two areas in Kyushu, western Japan. In a small estuary in Kagoshima Bay, where seven eel guts were examined, almost all of the dietary organisms consisted of Hemigrapsus crabs and Hediste polychaetes, both of which commonly occurred on tidal flats of this site during our survey on the macrobenthic fauna. In another large estuary in the innermost part of the Ariake Sea, where 14 eel guts were examined, 11 macrobenthic species (nine crustaceans, a polychaete, and a gastropod) were found in the gut contents, mostly consisting of mudflat-specific species. The dietary items are almost completely different not only between the two estuaries, but also among three neighboring sites within the large estuary in the Ariake Sea. These results show that Japanese eels feed on various macrobenthic invertebrates inhabiting estuarine tidal flats at each site. The variety of the prey species occupying different habitats indicates that their foraging areas extend to a wide range of estuarine tidal flats from the upper to lower littoral zones. The physalopterid nematode Heliconema anguillae was found parasitic in eel stomachs in both estuaries. The prevalence of the nematode was higher in the estuary in Kagoshima Bay (100%) than that in the Ariake Sea (43%), although the intensity in the former (4-94 nematodes per infected stomach) was comparable to that of the latter (2-96). The relationship between the nematode infection and the dietary items of Japanese eels is discussed.

  1. Changes in serum thyroid hormone levels and thyroid gland activity of artificially maturing female Japanese eel (Anguilla japonica)

    Institute of Scientific and Technical Information of China (English)

    Qu Xiancheng(曲宪成); Massaki Nagae; Sinji Adachi; Kohei Yamauchi

    2003-01-01

    In order to evaluate the involvement of the thyroid gland in reproduction, thyroid func-tioning was described in female cultivated Japanese eel (Anguilla japonica ) in progressive stages of sex-ual maturation induced by chum salmon pituitary homogenate (SPH) treatment. Serum thyroid hor-mones, thyroxine (T4) and triiodothyronine (T3) were also measured in each stage. Thyroid gland ac-tivity (epithelial cell height) was high before SPH injection (previtellogenic stage), further increasing at the early vitellogenic stage, thereafter decreasing to late vitellogenic and migratory nucleus stages. Theprofiles of both T3 and T4 changed during vitellogenesis, being high during previtellogenic and earlyvitellogenic stages, and subsequently declining, thus mimicking thyroid gland activity. These resultssuggest that the thyroid has relation with eel ovarian development during artificial maturation.

  2. Cardio-respiratory Physiology of the European Eel (Agunilla anguilla) in Extreme Environments

    DEFF Research Database (Denmark)

    Methling, Caroline

    ) is a common phenomenon in aquaculture facilities of A. anguilla. In Paper III it is demonstrated, that when exposed to a constant high level of hypercapnia (60mmHg), eels took a longer time (22%) to digest a meal size of fixed proportions (0.5% body weight) compared to eels held under normocapnic conditions......, while eels exposed to oscillating CO2 partial pressures (20-60mmHg) had a reduced post-prandial ammonia excretion. This suggests that depending on the specific conditions, hypercapnia may limit the appetite and feed intake as it takes longer time to process a meal, and/or that a smaller amount...... rate (AMR) as well as aerobic metabolic scope remained unaffected, which suggests that the observed effects were caused by increased drag. Swimming with a tag decreased the critical swimming speed (Ucrit) and also altered swimming kinematics as verified by significant changes to tail beat frequency (f...

  3. [Risk factors of ciguatera in the French West Indies in Saint-Barthélémy, Saint-Martin and Anguilla].

    Science.gov (United States)

    Bourdeau, P; Bagnis, R

    1989-01-01

    An epidemiological study on ciguatera fish poisoning in the French West Indies (St-Barthelemy, St-Martin and Anguilla) was conducted during the years 1985-1986. The investigation on intoxications shows a non seasonal significant prevalence. Though it was difficult to list the cases, the morbidity seems to vary between 7 and 30 per thousand. A study of fish toxicity was realised; 46 different species were tested (individually or by pools) by the mosquito bio-test. Observations of intoxications give the following results: High risk species: Caranx bartholomaei, C. lugubris, Seriola dumerili, Lutjanus apodus, L. jocu, Pristipomoides macrophtalmus, Gymnothorax funebris, G. moringa, Scomberomorus cavalla, S. regalis, Mycteroperca venenosa, M. tigris, Epinephelus morio, Sphyraena barracuda. Intermediate species: Caranx latus, C. ruber, Lachnolaimus maximus, Lutjanus analis, L. buccanella, L. griseus, Malacanthus plumieri, Scomberomorus maculatus. Low risk species: Balistes vetula, Alectis ciliaris, Haemulon album, Bodianus rufus, Halichoeres radiatus, Priacanthus arenatus, Alphestes afer. Many species are involved in the toxic food chain. New ones have been identified, but it is difficult to determine the toxic level range. A cartography is presented but no place is free of risk. A research of Gambierdiscus toxicus, the causal agent, on algal surface from dead corals was conducted around St-Barthelemy and St-Martin. The dinoflagellate is found in low or medium populations all around the islands with no difference between North and South. There is a maximal activity during the spring. A model of the epidemiology of the ciguatera in the area is proposed.

  4. Histological Features of the Gastrointestinal Tract of Wild Indonesian Shortfin Eel, Anguilla bicolor bicolor (McClelland, 1844, Captured in Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Nurrul Shaqinah Nasruddin

    2014-01-01

    Full Text Available This study was conducted to record the histological features of the gastrointestinal tract of wild Indonesian shortfin eel, Anguilla bicolor bicolor (McClelland, 1844, captured in Peninsular Malaysia. The gastrointestinal tract was segmented into the oesophagus, stomach, and intestine. Then, the oesophagus was divided into five (first to fifth, the stomach into two (cardiac and pyloric, and the intestine into four segments (anterior, intermediate, posterior, and rectum for histological examinations. The stomach had significantly taller villi and thicker inner circular muscles compared to the intestine and oesophagus. The lamina propria was thickest in stomach, significantly when compared with oesophagus, but not with the intestine. However, the intestine showed significantly thicker outer longitudinal muscle while gastric glands were observed only in the stomach. The histological features were closely associated with the functions of the different segments of the gastrointestinal tract. In conclusion, the histological features of the gastrointestinal tract of A. b. bicolor are consistent with the feeding habit of a carnivorous fish.

  5. The Use of Water Exchange for Feeding Rate and Growth Promotion of Shortfin Eel Anguilla bicolor bicolor In Recirculating Water System

    Science.gov (United States)

    Taufiq-Spj, N.; Sunaryo, S.; Wirasatriya, A.; Sugianto, D. N.

    2017-02-01

    The shortage of eel’s seed Anguilla spp. and it’s consumption size will induce the hunting of this species. Thus, stocks are critically endangered. Central Java have two indigenious species i.e. A. marmorata and A. bicolor bicolor. These two species will be endanger if management of stock do not conduct properly. The use of water exchange by replacing water volume for feeding rate and growth promotion of Indonesian shortfin eel A. bicolor bicolor in RWS will at least give a basic information in appropriate aquaculture systems and as a part of disaster mitigation of indegenious species extinction. The study used 3 replications and 3 treatments of water exchange, i.e. T1: 50, T2: 100, and T3: 200 % of water removed d-1. The fish were fed with approx. 2.2% dry basis of formulated feed. Tanks with volume of 1 m3 contain a density of approx. 20 kg seed stock of shortfin eel fingerlink size per m3 water in RSW. The result shows that feeding rate among treatments are significantly different (α water exchange (α water exchange (α < 0.001). Where for IAG: T1= 55.42±3.69, T2= 71.02±2.40, T3= 106.12±1.98% and BAG: T1= 35.11±1.13, T2= 52.94±6.17, T3= 90.77±3.14% respectively.

  6. Distribution of trace metals and methylmercury in soft tissues of the freshwater eel Anguilla marmorata in Vietnam.

    Science.gov (United States)

    Le, Dung Quang; Nguyen, Duc Cu; Harino, Hiroya; Kakutani, Naoya; Chino, Naoko; Arai, Takaomi

    2010-08-01

    This study investigated trace metals in water, sediment, and various organs of the mature eel Anguilla marmorata in the Ba River, Vietnam. The metal concentrations in water and sediment did not exceed the Vietnam water criteria and sediment background concentration, except for Mn and Pb in sediment. The results of metal analysis in eel specimens indicated that the liver and kidney were the dominant organs for almost all trace metals, whereas muscle tended to accumulate high levels of Hg and approximately 87.4-100% of Hg was methylmercury. A strong positive correlation between mercury levels in muscle and age were found, but there was no correlation between mercury and body size. Interestingly, a high concentration of Zn was found in the gonad and liver; this indicated that high levels of Zn in the liver might play a physiologically important role in the eel's biological mechanisms during gonadal maturation. Though almost none of the metal concentrations in the muscle exceeded the reference doses of the U.S. EPA, approximately 80% of eels from the river contained mercury exceeding the recommended levels (0.30 microg/g) of the U.S. EPA and might present a risk for human consumption.

  7. PENGARUH PENGGUNAAN TEPUNG SILASE DAUN MENGKUDU (Morinda citrifolia DALAM FORMULA PAKAN TERHADAP PERTUMBUHAN IKAN SIDAT (Anguilla bicolor STADIA ELVER

    Directory of Open Access Journals (Sweden)

    Dewi Cholifah

    2012-10-01

    Full Text Available Penelitian ini dilakukan untuk mengetahui pengaruh dan dosis terbaik penggunaan tepung silase daun Mengkudu (M. citrifolia dalam formula pakan terhadap pertumbuhan ikan Sidat (A. bicolor stadia elver. Penelitian dibagi menjadi dua tahap, tahap pertama formulasi pakan percobaan, dan tahap kedua uji in vivo/uji formula pakan percobaan skala laboratorium pada ikan Sidat. Pelaksanaan penelitian tahap 1 adalah membuat formula pakan iso protein (40% dan iso energi (3.600 kkal/kg pakan dengan memanfaatkan tepung silase daun Mengkudu sesuai perlakuan, menggunakan metode lembar kerja. Penelitian tahap 2 berdasarkan Rancangan Acak Lengkap (RAL dengan tiga ulangan. Empat perlakuan substitusi protein tepung silase daun Mengkudu terhadap protein tepung ikan yang berbeda, meliputi perlakuan A 0%(0:100; B 10%(10:90; C 20%(20:80 dan D 30%(30:70. Parameter utama adalah kelulushidupan (survival rate, laju pertumbuhan spesifik (specific growth rate, rasio konversi pakan (feed convertion ratio dan rasio efisiensi protein (protein efficiency ratio. Hasil penelitian menunjukkan bahwa penggunaan tepung silase daun Mengkudu dalam formula pakan berpengaruh nyata terhadap parameter laju pertumbuhan spesifik, rasio konversi pakan dan rasio efisiensi protein. Dosis terbaik tepung silase daun Mengkudu  mensubstitusi protein tepung ikan dalam formula pakan sebesar 14,71 – 15% yang menghasilkan nilai laju pertumbuhan spesifik 0,72 %BB/hari, rasio konversi pakan 3,38, dan rasio efisiensi protein 0,718.Kata kunci: formula pakan, silase daun Morinda citrifolia, Anguilla bicolor

  8. A combination mode of climate variability responsible for extremely poor recruitment of the Japanese eel (Anguilla japonica)

    Science.gov (United States)

    Lin, Yong-Fu; Wu, Chau-Ron; Han, Yu-San

    2017-03-01

    Satellite data and assimilation products are used to investigate fluctuations in the catch of Japanese eel (Anguilla japonica) in eastern Asian countries. It has been reported that the salinity front has extended farther south, which has shifted the eel’s spawning grounds to a lower latitude, resulting in smaller eel catches in 1983, 1992, and 1998. This study demonstrates that interannual variability in the eel catch is strongly correlated with the combination mode (C-mode), but not with the El Niño–Southern Oscillation. These eels continue to spawn within the North Equatorial Current (NEC), but the salinity front shifts south during a canonical El Niño. On the other hand, the spawning grounds accompanied by the salinity front extend farther south during the C-mode of climate variability, and eel larvae fail to join the nursery in the NEC, resulting in extremely poor recruitment in East Asia. We propose an appropriate sea surface temperature index to project Japanese eel larval catch.

  9. The effect of nearly closed RAS on the feed intake and growth of Nile tilapia (Oreochromis niloticus), African catfish (Clarias gariepinus) and European eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Mota, V.C.; Limbu, P.; Martins, C.I.; Eding, E.H.; Verreth, J.A.J.

    2015-01-01

    One of the challenges that Recirculating Aquaculture Systems (RAS) are still facing is the risk that in RAS fish grow less than in flow-through systems due to the accumulation of substances originating from feed, fish or bacteria associated with the water re-use. The present study investigated wheth

  10. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation.

    Science.gov (United States)

    Kalujnaia, Svetlana; Hazon, Neil; Cramb, Gordon

    2016-08-01

    A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells.

  11. Determination of Weaning Regimes for Anguilla mormorata Glass Eels%菲律宾鳗鲡(Anguilla mormorata)鳗苗训饵及转料方法研究

    Institute of Scientific and Technical Information of China (English)

    徐长安; 施建臣; 唐旭; 方卫东; 郭康姣

    2013-01-01

    The aim was to find a suitable weaning regime,including weaning period and weaning feed,for Anguilla mormorata glass eels.[Method] A weaning processing experiment was conducted indoor in fiberglass tanks,two kinds of artificial feeds (eel grower powder feed and eel grower piece feed) were selected as weaning diets against a control group fed on natural food (minced octopus flesh),two weaning periods,5 and 15 d,were introduced in weaning experiment.[Result]The growth rate and survival rate of the groups with 15-day's weaning period were higher than that of the groups with 5-day's weaning period,revealing that a 20% increase every 3 d from 0% to 100% in the proportion of grower paste in the minced octopus flesh during weaning is suitable for A.mormorata glass eels.[Conclusion] A.mormorata glass eels can be weaned from natural food to the commercially available eel grower feeds over a certain weaning period,and of the artificial feeds with same ingredients and nutrient,A.mormorata glass eels accepted powder feed more readily over 28 d than piece feed.%[目的]研究探索适合于菲律宾鳗鲡仔鳗的训饵及转料方法.[方法]在室内纤维玻璃桶中开展训饵转料实验,选择人工饲料中的仔鳗粉状料和仔鳗粉碎料作为实验料,以天然新鲜章鱼糜作为对照料,设定5天和15天两个转料周期.[结果]15天转料周期的仔鳗成长率和存活率明显高于5天转料周期,每间隔3天以20%占比的速率把天然的新鲜章鱼靡替换成人工仔鳗料的转料方式,适合于菲律宾鳗鲡仔鳗的训饵转料.[结论]菲律宾鳗鲡仔鳗经过一定周期的训饵转料,能从天然饵料转到商业人工饲料,在营养成分和营养价值等同的人工饲料中,比起粉碎料,菲律宾鳗鲡仔鳗更适合接受粉状料.

  12. Molecular cloning of Japanese eel Anguilla japonica TNF-α and characterization of its expression in response to LPS, poly I:C and Aeromonas hydrophila infection

    Science.gov (United States)

    Feng, Jianjun; Guan, Ruizhang; Guo, Songlin; Lin, Peng; Zadlock, Frank

    2014-09-01

    As a potent pleiotropic cytokine, tumor necrosis factor-alpha (TNF-α) plays an important role in innate immune responses. The cDNA sequence and genomic structure of the TNF-α gene ( Aj TNF-α) in the Japanese eel ( Anguilla japonica) were identified and characterized. The full-length AjTNF-α cDNA was 1 546 bp, including a 5'-untranslated region (UTR) of 13 bp, a 3'-UTR of 879 bp and an open reading frame of 654 bp encoding a protein of 218 amino acids. The full-length genomic sequence of AjTNF-α was 2 392 bp and included four exons and three introns. The putative AjTNF-α protein contained TNF family signature motifs, including a protease cleavage site, a transmembrane domain and two conserved cysteine residues. Quantitative real-time reverse transcription PCR analysis revealed AjTNF-α expression in a wide range of tissues, with predominant expression in blood and liver. Lower levels of expression were seen in spleen, gills, kidney, intestine, heart, and skin, with very low levels in muscle. The modulation of AjTNF-α expression after injection of eels with lipopolysaccharide (LPS), the viral mimic, poly I:C, or Aeromonas hydrophila was assessed in blood, liver, and kidney. In blood, TNF-α mRNA levels increased rapidly and then rapidly decreased after stimulation with LPS, poly I:C or A. hydrophila. However, the response to LPS and A. hydrophila peaked at 6 h while for poly I:C the peak was at 12 h. In liver, after injection with A. hydrophila, an up- and down-regulation of AjTNF-α expression occurred twice, peaking at 6 h and 24 h, respectively. No remarkable increase of AjTNF-α expression appeared in liver until 72 h after LPS or poly I:C treatment. In kidney, AjTNF-α expression increased significantly only at 72 h post-stimulation with LPS or A. hydrophila. Our results suggest that AjTNF-α plays an important role in fish in the defense against viral and bacterial infection.

  13. Shark predation on migrating adult american eels (Anguilla rostrata) in the Gulf of St. Lawrence

    DEFF Research Database (Denmark)

    Béguer-Pon, Mélanie; Benchetrit, José; Castonguay, Martin;

    2012-01-01

    to identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria...... generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit...... itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent...

  14. Shark predation on migrating adult American eels (Anguilla rostrata in the Gulf of St. Lawrence.

    Directory of Open Access Journals (Sweden)

    Mélanie Béguer-Pon

    Full Text Available In an attempt to document the migratory pathways and the environmental conditions encountered by American eels during their oceanic migration to the Sargasso Sea, we tagged eight silver eels with miniature satellite pop-up tags during their migration from the St. Lawrence River in Québec, Canada. Surprisingly, of the seven tags that successfully transmitted archived data, six were ingested by warm-gutted predators, as observed by a sudden increase in water temperature. Gut temperatures were in the range of 20 to 25°C-too cold for marine mammals but within the range of endothermic fish. In order to identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit diel vertical migrations. Three eels were eaten at this time. Two eels exhibited inverse diel vertical migrations (at surface during the day during several days prior to predation. Four eels were eaten during daytime, whereas the two night-predation events occurred at full moon. Although tagging itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent a reliable, predictable food resource for porbeagle sharks.

  15. 花鳗鲡鱼体肌肉的氨基酸分析研究%Amino Acid Analysis of Anguilla Marmorata Muscle

    Institute of Scientific and Technical Information of China (English)

    林香信; 颜孙安; 钱爱萍; 姚清华; 宋永康

    2012-01-01

    In order to explore the nutritional efficacy of Anguilla Marmorata Muscle in different sizes, and assist person taking reasonable consumption concept, the amino acid composition model in Anguilla marmorata with different sizes (3 groups: A: 360-420 g; B: 250-300 g; C: 200-250 g) were analysed. The results showed that Anguilla marmorata muscle content 18 kinds of amino acids, the proportion of them were 14.4%, 18.30% and 18.16% in group A, B, C separately. The contents of Glu was the highest in all groups. And the order of essential amino acid and EAA/TAA was similar in 3 groups. The contents of amino acid with different function in 3 groups were as followed: sweetness amino acids (A:6.91%, B:8.73% C:9.37%), bitterness amino acids (A: 5.46%, B:6.96%, C:6.94%), tartness amino acids (A:3.71%, B:4.87%, C:4.87%), delicious amino acids (A: 3.22%, B:4.22%, C:4.19%), drug-effective amino acids (A:9.33%, B:11.93%, C:12.56%). The conclusion was that Anguilla marmorata was a aquatic product having medicine and food function. And Anguilla marmorata with body weigt 250-300 g have better food function, the ones with body weigt 200-250 g have better medicine function.%为了探讨不同体重花鳗鲡鱼体肌肉氨基酸的营养功效,指导消费者合理消费.本研究比较了不同体重(A组:360~420 g;B组:250~300 g;C组:200~250 g)花鳗鲡肌肉蛋白质的氨基酸组成,并分析了其必需氨基酸、呈味氨基酸、药效氨基酸含量.结果表明:花鳗鲡肌肉含有18种氨基酸,氨基酸总量分别达14.40%、18.30%、18.16%,谷氨酸含量最高.不同组别花鳗鲡的8种人体必需氨基酸含量高低顺序一致,占氨基酸总量的比例分别41.60%、41.63%、41.63%,呈味氨基酸的分布依次为甜味类氨基酸含量(A组:6.91%;B组:8.73%;C组:9.37%)、苦味类氨基酸含量(A组:5.46%;B组:6.96%;C组:6.94%)、酸味类氨基酸含量(A组:3.71%;B组:4.87%;C组:4.87%)、鲜味类氨基酸含量(A组:3

  16. 花鳗鲡病原菌弗氏柠檬酸杆菌的鉴定%Identification of Pathogenic Citrobacter freundii Isolated from Anguilla marmorata

    Institute of Scientific and Technical Information of China (English)

    杨方园; 关瑞章; 李忠琴; 于海振; 李秋云

    2013-01-01

    首次报道了从养殖花鳗鲡(Anguilla marmorata)肝脏中分离得到优势菌株AMRB6,经人工腹腔注射感染健康花鳗鲡试验,结果证实该菌有致病作用,其半数致死量LD50为3.2×107 CFU/mL.结合菌体形态特征、常规生理生化鉴定和Biolog自动微生物鉴定系统鉴定,以及16S rRNA序列扩增结果,表明该菌为弗氏柠檬酸杆菌(Citrobacter freundii).30种药物药敏试验结果表明,该菌株对左氧氟沙星、诺氟沙星、庆大霉素、卡那霉素等14种药物高度敏感.

  17. A novel recombinant bivalent outer membrane protein of Vibrio vulnificus and Aeromonas hydrophila as a vaccine antigen of American eel (Anguilla rostrata).

    Science.gov (United States)

    SongLin, Guo; PanPan, Lu; JianJun, Feng; JinPing, Zhao; Peng, Lin; LiHua, Duan

    2015-04-01

    The immogenicity of a novel vaccine antigen was evaluated after immunized American eels (Anguilla rostrata) with a recombinant bivalent expressed outer membrane protein (OMP) of Vibrio vulnificus and Aeromonas hydrophila. Three groups of eels were intraperitoneal (i.p) injected with phosphate-buffered saline (PBS group), formaline-killed-whole-cell (FKC) of A. hydrophila and V. vulnificus (FKC group) or the bivalent OMP (OMP group). On 14, 21, 28 and 42 days post-vaccination respectively, proliferation of the whole blood cells, titers of specific antibody and lysozyme activities of experimental eels were detected. On 28 day post-vaccination, eels from three groups were challenged by i.p injection of live A. hydrophila or V. vulnificus. The results showed that, compared with the PBS group, proliferation of whole blood cells in OMP group was significant enhanced on 28 days, and the serum titers of anti-A.hydrophila and anti-V. vulnificus antibody in eels of FKC and OMP group were significant increased on 14, 21 and 28d. Lysozyme Activities in serum, skin mucus, liver and kidney were significant changed between the three groups. Relative Percent Survival (RPS) after challenged A. hydrophila in KFC vs. PBS group and OMP vs. PBS group were 62.5% and 50% respectively, and the RPS challenged V. vulnificus in FKC and OMP vs. PBS group were 37.5% and 50% respectively. These results suggest that American eels immunized with the bivalent OMP would positively affect specific as well as non-specific immune parameters and protect against infection by the two pathogens in fresh water farming. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. A review on broodstock nutrition of marine pelagic spawners: the curious case of the freshwater eels (Anguilla spp.)

    DEFF Research Database (Denmark)

    Heinsbroek, L.T.N.; Støttrup, J.G.; Jacobsen, C.

    2013-01-01

    a large amount of total lipids, and a shortage of neutral lipids has been implied a cause for reduced survival of larvae. Eel eggs have higher ARA but lower EPA and DHA levels than in other fish. Too high levels of ARA negatively affected reproduction in the Japanese eel, although high levels of 18:2n‐6...

  19. Tolerance of hypercapnic acidosis by the European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    McKenzie, DJ; Dalla Valle, AZ; Steffensen, JF

    2000-01-01

    content (ca,O2) from 9.6 ± 0.7 to 2.0 ± 0.5 vol%. There was a significant increase in fG and POP at Pw,CO2 values of 10, 20, 40 mmHg, then a decline in fG but further increase in POP at Pw,CO2 = 60 and 80 mmHg. Despite the severe acidosis and hypoxaemia, there were no significant effects on CO or O2...... in tailbeat frequencies, aerobic scope or maximum sustainable swimming speed. The results indicate that the eel is extremely tolerant of hypercapnic acidosis. Acute, severe acidosis and hypoxaemia had no effect on CO or whole animal O2 uptake; chronic acidosis and hypoxaemia had no effect on the ability...

  20. Tolerance of chronic hypercapnia by the European eel Anguilla anguilla

    DEFF Research Database (Denmark)

    McKenzie, D J; Piccolella, M; Dalla Valle, A Z

    2003-01-01

    European eels were exposed for 6 weeks to water CO(2) partial pressures (P(CO)(2)) from ambient (approx. 0.8 mmHg), through 15+/-1 mmHg and 30+/-1 mmHg to 45+/-1 mmHg in water with a total hardness of 240 mg l(-1) as CaCO(3), pH 8.2, at 23+/-1 degrees C. Arterial plasma P(CO)(2) equilibrated...... at approximately 2 mmHg above water P(CO)(2) in all groups, and plasma bicarbonate accumulated up to 72 mmol l(-1) in the group at a water P(CO)(2) of 45 mmHg. This was associated with an equimolar loss of plasma Cl(-), which declined to 71 mmol l(-1) at the highest water P(CO)(2). Despite this, extracellular acid...

  1. Growth observations on European (Anguilla anguilla L. and American (Anguilla rostrata Le Sueur glass eels

    Directory of Open Access Journals (Sweden)

    APPELBAUM S.

    1998-04-01

    (x = 0.167 ± 0.006 g. After 45 days of rearing, the weight differences between the species became insignificant. Except for the different transportation mortalities on arrival, the European and the American eels demonstrated similar mortality rates during the experiment ( 1 2 . 5 % , food conversion rate (2.3 and specific growth rate (0.90 and 0.99 respectively. No parasites or diseases were detected. No differences were observed in general behaviour and feeding between the two species.

  2. Application of Complex Microbial Preparation to Intensive Aquaculture of Anguilla japonica in Earth-ponds%复合微生物制剂在日本鳗鲡土池精养中的应用

    Institute of Scientific and Technical Information of China (English)

    江兴龙; 耿英慧; Pornlerd Chanratchakool; 刘永光; 熊萍

    2012-01-01

    2009年7月至2010年2月,对日本鳗鲡(Anguilla japonica)土池精养池定期施用复合微生物制剂(Freshplus 净水剂),监测处理组和对照组池塘的水温、pH、溶氧、氨氮、亚硝酸盐氮、硝酸盐氮、COD、碱度等水质指标,并分析对比其养殖效果.结果表明,Freshplus净水剂的施用能显著降低鳗鲡土池水体氨氮浓度60.5% (P <0.05),显著提高其生长速度33.0% (P <0.05),降低饲料系数9.6%(a=0.1,P<0.1).

  3. Cadmium concentration in three species of freshwater fishes from Keuretoe River, Northern Aceh, Indonesia

    OpenAIRE

    Muhammad A. Sarong; Abdul L. Mawardi; Muhammad Adlim; Zainal A.Muchlisin

    2013-01-01

    The objectives of present study was to evaluate cadmium (Cd) concentration in some freshwater fishes found in Keuretoe Rivers and to determine the most effective freshwater fishes (Osphronemus goramy, Anguilla marmorata and Hemibagrus nemurus) in accumulating of cadmium. A total of three sampling locations were determined using the purposive of random sampling. A total of three individual fishes at every sampling location were collected, the tissues were processed for Atomic ...

  4. De Novo Assembly of the Whole Transcriptome of the Wild Embryo, Preleptocephalus, Leptocephalus, and Glass Eel of Anguilla japonica and Deciphering the Digestive and Absorptive Capacities during Early Development.

    Science.gov (United States)

    Hsu, Hsiang-Yi; Chen, Shu-Hwa; Cha, Yuh-Ru; Tsukamoto, Katsumi; Lin, Chung-Yen; Han, Yu-San

    2015-01-01

    Natural stocks of Japanese eel (Anguilla japonica) have decreased drastically because of overfishing, habitat destruction, and changes in the ocean environment over the past few decades. However, to date, artificial mass production of glass eels is far from reality because of the lack of appropriate feed for the eel larvae. In this study, wild glass eel, leptocephali, preleptocephali, and embryos were collected to conduct RNA-seq. Approximately 279 million reads were generated and assembled into 224,043 transcripts. The transcript levels of genes coding for digestive enzymes and nutrient transporters were investigated to estimate the capacities for nutrient digestion and absorption during early development. The results showed that the transcript levels of protein digestion enzymes were higher than those of carbohydrate and lipid digestion enzymes in the preleptocephali and leptocephali, and the transcript levels of amino acid transporters were also higher than those of glucose and fructose transporters and the cholesterol transporter. In addition, the transcript levels of glucose and fructose transporters were significantly raising in the leptocephali. Moreover, the transcript levels of protein, carbohydrate, and lipid digestion enzymes were balanced in the glass eel, but the transcript levels of amino acid transporters were higher than those of glucose and cholesterol transporters. These findings implied that preleptocephali and leptocephali prefer high-protein food, and the nutritional requirements of monosaccharides and lipids for the eel larvae vary with growth. An online database (http://molas.iis.sinica.edu.tw/jpeel/) that will provide the sequences and the annotated results of assembled transcripts was established for the eel research community.

  5. De Novo Assembly of the Whole Transcriptome of the Wild Embryo, Preleptocephalus, Leptocephalus, and Glass Eel of Anguilla japonica and Deciphering the Digestive and Absorptive Capacities during Early Development.

    Directory of Open Access Journals (Sweden)

    Hsiang-Yi Hsu

    Full Text Available Natural stocks of Japanese eel (Anguilla japonica have decreased drastically because of overfishing, habitat destruction, and changes in the ocean environment over the past few decades. However, to date, artificial mass production of glass eels is far from reality because of the lack of appropriate feed for the eel larvae. In this study, wild glass eel, leptocephali, preleptocephali, and embryos were collected to conduct RNA-seq. Approximately 279 million reads were generated and assembled into 224,043 transcripts. The transcript levels of genes coding for digestive enzymes and nutrient transporters were investigated to estimate the capacities for nutrient digestion and absorption during early development. The results showed that the transcript levels of protein digestion enzymes were higher than those of carbohydrate and lipid digestion enzymes in the preleptocephali and leptocephali, and the transcript levels of amino acid transporters were also higher than those of glucose and fructose transporters and the cholesterol transporter. In addition, the transcript levels of glucose and fructose transporters were significantly raising in the leptocephali. Moreover, the transcript levels of protein, carbohydrate, and lipid digestion enzymes were balanced in the glass eel, but the transcript levels of amino acid transporters were higher than those of glucose and cholesterol transporters. These findings implied that preleptocephali and leptocephali prefer high-protein food, and the nutritional requirements of monosaccharides and lipids for the eel larvae vary with growth. An online database (http://molas.iis.sinica.edu.tw/jpeel/ that will provide the sequences and the annotated results of assembled transcripts was established for the eel research community.

  6. Content comparison of polycyclic aromatic hydrocarbons (PAHs in traditionally smoked freshwater fish

    Directory of Open Access Journals (Sweden)

    Renata Pietrzak-Fiećko

    2015-09-01

    Full Text Available The aim of this study was to compare the content of chosen PAHs (benzo[a]pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene in meat of different freshwater fish species that were traditionally (directly smoked. The survey covered 16 freshwater fish samples of four species: rainbow trout (Oncorhynchus mykiss, carp (Cyprinus carpio, vendace (Coregonus albula and eel (Anguilla anguilla. Average content of sum of four PAHs in meat of trout, carp, vendace and eel was: 2.73, 8.23, 6.45 and 3.65 µg/kg of meat, respectively. Maximum levels of chosen PAHs in meat of examined fish species were not exceeded by any of the samples. Conducted studies confirmed that meat of traditionally smoked trout, carp, vendace and eel is safe in terms of content of the analysed PAHs.

  7. Application of Complex Microbial Preparation to Intensive Aquaculture of Anguilla japonica in Earth-ponds%复合微生物制剂在日本鳗鲡土池精养中的应用

    Institute of Scientific and Technical Information of China (English)

    江兴龙; 耿英慧; Pomlerd Chanratehakool; 刘永光; 熊萍

    2012-01-01

    2009年7月至2010年2月,对日本鳗鲡(Anguillajaponica)土池精养池定期施用复合微生物制剂(Freshplus净水剂),监测处理组和对照组池塘的水温、pH、溶氧、氨氮、亚硝酸盐氮、硝酸盐氮、COD、碱度等水质指标,并分析对比其养殖效果。结果表明,Freshplus净水剂的施用能显著降低鳗鲡土池水体氨氮浓度60.5%(P〈0.05),显著提高其生长速度33.0%(P〈0.05),降低饲料系数9.6%(a=0.1,P〈0.1)。%The comparison trial was implemented on the microbial preparation, "Freshplus" water cleaning agent, which was applied regularly in the earth-ponds for Japanese eel (Anguilla japonica) intensive aquaculture. The wa- ter quality parameters in the control ponds and the treatment ponds, namely, water temperature, pH, dissolved ox- ygen, total ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, COD and alkalinity, were measured at intervals, and the breeding results were analysed. The results showed that: the treatment of "Freshplus" cleaning agent great- ly reduced the concentration of total ammonium nitrogen in eel cultivation water, i.e. 60.5 % ( P 〈 0.05 ) lower than the control, increased the eel growth rate, 33.0% (P 〈 0.05) higher than the control, and decreased the feed conversion ratio, 9.6% (a =0. 1 ,P 〈0.1 ) lower than the control.

  8. 日本鳗鲡及其僵鳗消化酶活性的比较研究%Comparison of Digestive Enzyme Activities in Normal and Growth Retarded Japanese Eels (Anguilla japonics)

    Institute of Scientific and Technical Information of China (English)

    黄永春

    2012-01-01

    This experiment was conducted to study the effects of temperatures on the activities of digestive enzymes in Japanese eels Anguilla japonics (n = 20) and growth retarded eels (n =20). The weight of the normal eels was from 126. 4 to 140. 2 g per eel, and that of growth retarded eels was from 3. 5 to 8. 6 g per eel. The activities of protease, amylase, and lipase in the normal eels and growth retarded eels under the condition of different temperatures (5, 10, 15, 25, 30, 35, 40, 45 and 55 ℃) were studied. The results showed as follows: with the increasing of temperature, the digestive enzyme activities were increased at first, and then decreased. The optimum temperature of the protease in hepatopancreas, intestine and stomach was 45 ℃. In the same experimental temperature, the order of protease activity was intestine > stomach > hepatopancreas except growth retarded eels at 5 , 15 and 55 ℃. The protease activity in hepatopancreas, intestine and stomach of growth retarded eels was only 29. 5% , 15. 7% and 25. 2% of that of the normal eels, respectively (P intestine > stomach in experimental temperatures except at 5 ℃, but the order of amylase activity of growth retarded eels was intestine > hepatopancreas > stomach in experimental temperatures. The amylase activity in hepatopancreas, intestine and stomach of growth retarded eels was only 42. 4% , 73. 7% and 43. 8% of that of the normal eels, respectively (P stomach > intestine in experimental temperatures, but the order of lipase activity of growth retarded eels was hepatopancreas > intestine > stomach in experimental temperatures except at 35 ℃; the lipase activity in hepatopancreas, intestine and stomach of growth retarded eels was only 41. 5% , 45. 6% and 23. 2% of that of the normal eels, respectively (P <0. 05). These results indicate that the activities of protease, amylase and lipase in hepatopancreas, intestine and stomach of growth retarded eels are significantly lower than those of normal eels

  9. Comparative Study on Test Methods for Antibacterial Activities of Antibacterial Peptides from Spleen of Japanese Eel (Anguilla japonica)%日本鳗鲡脾脏抗菌肽抗菌活性检测方法的比较

    Institute of Scientific and Technical Information of China (English)

    梁英; 黄文树; 关瑞章

    2014-01-01

    The study was to establish a simple and sensitive test method for antibacterial activity analysis in the separation and purification of antibacterial peptides from the spleen of Japanese eel ( Anguilla japonica) . Exper-iment by using spleen protein of molecular mass<10 ku from Japanese eel as antibacterial peptide samples, to compare the sensitivity, advantages and disadvantages of three test methods. In these three test methods, two conventional methods were agar plate fovea diffusion method and microporous liquid culture method and anoth-er was trace liquid culture method, for testing antibacterial activities of antibacterial peptides against three com-mon pathogenic bacterial strains of eel, including Edwardsiella tarda, Aeromonas sp. and Aeromonas hy-drophila. The results showed that compared with the agar plate fovea diffusion method and microporous liquid culture method, the trace liquid culture method had the advantages of simple operation and easy to observe re-sult. Furthermore, this method with the best sensitivity and using the least sample quantity could be suitable for testing antibacterial activities in the separation and purification of antibacterial peptides from the spleen of eel, especially for identifying antibacterial activity of the a few and single fraction obtained in late stage of separa-tion and purification. This study suggests that the trace liquid culture method is suitable for testing antibacterial activities of antibacterial peptides from the spleen of Japanese eel.%本试验旨在建立一种在日本鳗鲡脾脏抗菌肽分离纯化过程中简便、灵敏的检测其抗菌活性的方法。试验以日本鳗鲡脾脏分子质量小于10 ku的蛋白质为抗菌肽样品,选择琼脂板孔穴扩散法和微孔液体培养法2种传统方法及微量液体培养法为检测方法,比较这3种方法在抗菌肽对3种鳗鲡常见致病菌株(迟钝爱德华菌、气单胞菌、嗜水气单胞菌)抗菌活性检测中的灵

  10. 养殖日本鳗鲡腐皮病真菌性病原的分离与鉴定%ISOLATION AND IDENTIFICATION OF FUNGAL PATHOGEN FROM DERMAL ULCERATION DISEASE ON CULTURED ANGUILLA JAPONICA

    Institute of Scientific and Technical Information of China (English)

    曾占壮; 樊海平; 卓玉琛; 吴斌; 张新艳; 陈灵

    2011-01-01

    In recent years, dermal ulceration disease is one of the most serious diseases on cultured Japanese eels (An-guilla japonica), which occurs widely, spreads quickly and has caused great expense through the winter. In the beginning, the grume of the diseased eels are hyperplastic and then broken off. Following the evolvement of the illness, the derma is bareness and the muscle is necrotic. Eventually, the derma and the muscle are rotted.The isolation and identification of the fungal pathogen of this disease was studied. The fungal strain Js80122 was isolated from diseased eels by cultured on kernels of wheat. Strain Js80122 was confirmed as the causative pathogen of the dermal ulceration disease by artificial infection tests, which lasted for 2 weeks. In these tests, healthy eels were infected with four kinds of different methods, namely, injected with spores (0.3 mL/ind.) on dorsal muscle, marinated with 3 dish of culture after ravaged, daubed with spores(1.0x108 cell/mL)on wound and injected with spores and bacteria (0.3 mL/ind.) on dorsal muscle. The results showed that dermal ulceration disease could be recurred well on the experimental eels by any infection method; the symptom and process were similar to the naturally diseased eels. During the course of the artificial infection tests, the mortality were up to 100% in the group injected with spores (5.0x107 cell/mL) and bacteria (5.0x107CFU/mL) on dorsal muscle, 80% in the group injected with spores (l.OxlO8 cell/mL) on dorsal muscle, 60% in the group daubed with spores on wound, 20% in the group marinated with culture after ravaged, respectively. Observation on the morphology and life history of strain Js80122 cultured on slide and cover glass showed that strain Js80122 was the filamentous fungi and could grow well at 15℃, 20℃ and 25℃. Its hyphae were non-aseptate with plentiful branches, the reproductive modes were asexual and sexual. The asexual structure of Js80122 could be well produced at 20℃ or 25

  11. Biomass and number of fish impinged at a nuclear power plant by the Baltic Sea.

    Science.gov (United States)

    Bryhn, Andreas C; Bergenius, Mikaela A J; Dimberg, Peter H; Adill, Anders

    2013-12-01

    The main aim of this study was to investigate the number and biomass of impinged fish at Forsmark Nuclear Power Plant in Sweden, located on the coast of the Baltic Sea. Of particular interest was the number of impinged individuals of the critically endangered European eel (Anguilla anguilla) which is regularly caught in the cooling system. Another aim was to determine the comparability of the results from Forsmark and results from impingement studies in other types of waters. Cross-systems studies make it possible to (1) estimate fish loss at plants where fish is not counted, and (2) to predict changes in fish loss from changes in electricity production or cooling water use. In 2010, 31,300,000 fish with a total biomass of 62,600 kg were impinged at Forsmark. In 2011, 27,300,000 fish weighing 38,500 kg were impinged. The maximum peak in total fish number and biomass occurred in spring. The most critical period for herring was in late summer and early autumn. Regarding eel, the largest impingement losses were recorded in November. The number of fish agreed with earlier established quantities of impinged fish in both freshwater and marine ecosystems. The study also estimated that 1,300 critically endangered eels could survive at Forsmark each year if a fish return system would be constructed to allow the passage of fish from the plant back to the Baltic Sea.

  12. Variation in fish community structure, richness, and diversity in 56 Danish lakes with contrasting depth, size, and trophic state: does the method matter?

    DEFF Research Database (Denmark)

    Menezes, Rosemberg; Borchsenius, Finn; Svenning, J.-C.;

    2013-01-01

    for offshore samplings. Electrofishing was more efficient than gillnets at catching pike (Esox lucius), eel (Anguilla anguilla), and tench (Tinca tinca), whereas pelagic gillnets were better for catching pikeperch (Sander lucioperca) and perch (Perca fluviatilis). Independently of methods, the total number per...

  13. Variation in fish community structure, richness and diversity of 56 Danish lakes with contrasting depth and trophic state: Does the method matter?

    DEFF Research Database (Denmark)

    Menezes, Rosemberg

    2011-01-01

    depth (AVDEP). For electrofishing, AVDEP and SS were the best predictors selected for roach (Rutilus rutilus), tench (Tinca tinca), eel (Anguilla anguilla) and rudd (Scardinius erythrophtalmus), whereas for the littoral gill nets CHLA and SS were the best predictors for roach, perch (Perca fluviatilis...

  14. Freshwater fishes of Tsitsikamma National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2002-12-01

    Full Text Available This study aimed to determine the distribution and relative abundance of freshwater fishes in the Tsitsikamma National Park. Fish assemblages in six river systems were sampled in 2001, with a total of 323 fish from eight species recorded. Indigenous fish collected included four freshwater species (Pseudobarbus afer, Pseudobarbus tenuis, Sandelia capensis, Anguilla mossambica, three estuarine species (Monodactylus falciformis, Caffrogobius gilchristi, Myxus capensis, and one alien (Micropterus salmoides. One additional indigenous species (Galaxias zebratus and two aliens (Salmo trutta, Oncorhynchus mykiss could potentially occur within the park. The topography and locality of the park presents a unique opportunity to meaningfully conserve the endangered P. tenuis as well as other fish characteristic of the eastern reaches of the Cape Floristic Region. Management action is required to minimise opportunities for further establishment and spread of alien fish species and to conserve indigenous fish assemblages within the park.

  15. The migration behaviour of European silver eels (Anguilla anguilla) released in open ocean conditions

    DEFF Research Database (Denmark)

    Wysujack, K.; Westerberg, H.; Aarestrup, Kim

    2015-01-01

    with pop-up satellite transmitters and released at three different locations in the north-eastern Atlantic Ocean and in the Sargasso Sea. The study covers tracking periods between 7 and 92 days. The distance between release point and estimated pop-up position ranged from 40 to 1000 km, the mean minimum...

  16. Light impacts embryonic and early larval development of the European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Politis, Sebastian Nikitas; Butts, Ian; Tomkiewicz, Jonna

    2014-01-01

    intensity white (full spectrum, 10.5 μmol m-2 s-1), blue (~470 nm, 3.9 μmol m-2 s-1), green (~530 nm, 1.5 μmol m-2 s-1), and red light (~690 nm, 1.1 μmol m-2 s-1). Additionally, offspring were reared in continuous darkness (0:24 h light/dark). Results showed that light critically influenced early life...... in the 24:0 h light/dark photoperiod (13 ± 8%), and larvae reared in red light (22 ± 8%) had higher survival than those reared in green (14 ± 8%) or white light (11 ± 8%). Under continuous darkness, development and survival of offspring was as high as the best intensity-photoperiod-spectral composition......Little is known about the natural ecology of European eel during early life history. Weextend our understandings on the ecology of this species by studying howearly life stages perform under various light regimes.We assessed the effects of intensity, photoperiod (12:12 and 24:0 h light...

  17. Long-term tagging of elvers, Anguilla anguilla, with radioactive europium

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Fattah, A. T. A.

    1986-01-01

    Elvers were labeled with 152Eu and 155Eu. Optimum conditions turned out to be incubation for 3 h at 15.degree. C in artificial sea water containing 2% NaCl and 0.1% KCl, EuCl3 at 1 mCi (37 MBq) l-1 and an eel concentration of about 15%. Laboratory experiments pointed to a biological half-life of ...... then on average 56 g and showed no significant loss of label other than the physical half-life (5.1 years). All the radioactivity was found in bone tissue....

  18. Study of male reproductive physiology and sperm conservation in the european EEL ( Anguilla anguilla, L.)

    OpenAIRE

    Sánchez Peñaranda, David

    2011-01-01

    La anguila europea es una especie de gran importancia comercial en la acuicultura europea, pero el dramático descenso de las poblaciones naturales ha provocado la inclusión de esta especie en la lista CITES (convención del comercio internacional de especies en peligro de la fauna y flora salvaje). Considerando esta situación, se hace necesaria más investigación en el control reproductivo. El presente documento contiene 5 estudios que se pueden dividir en dos partes principales: la primera,...

  19. Speciation and demographic history of Atlantic eels (Anguilla anguilla and A. rostrata) revealed by mitogenome sequencing

    DEFF Research Database (Denmark)

    Jacobsen, M.W.; Pujolar, J.M.; Gilbert, M.T.P.

    2014-01-01

    , coinciding with the closure of the Panama Gateway that led to reinforcement of the Gulf Stream. This could have advected larvae towards European/North African coasts, in which case American eel would be expected to be the ancestral species. This scenario could, however, not be unequivocally confirmed...... for positive selection at the ATP6 and possibly ND5 genes, indicating a role in speciation. The findings suggest an important role of ocean current changes in speciation of marine organisms...

  20. Assessment of testis development during induced spermatogenesis in the European eel Anguilla anguilla

    DEFF Research Database (Denmark)

    Tomkiewicz, Jonna; Kofoed, Tanja; Pedersen, Jes S.

    2011-01-01

    for histological analysis of spermatogenesis. Testis development was followed over 18 weeks, during which the males continued to develop spermatocytes and produce spermatozoa. The SMI describes testis development from estimation of the area fractions of various tissue categories characterized by progressive gamete...

  1. Are dioxin-like contaminants responsible for the eel (Anguilla anguilla) drama?

    NARCIS (Netherlands)

    Palstra, A.P.; Ginneken, van V.J.T.; Murk, A.J.; Thillart, van den G.

    2006-01-01

    Eel populations worldwide are dangerously close to collapsing. Our study is the first to show that current levels of dioxin-like contaminants are strong candidates because of their devastating effects on development and survival of eel embryos. Female and male silver eels were artificially stimulate

  2. Association between trichodiniasis in eel ( Anguilla anguilla ) and water quality in recirculation systems

    DEFF Research Database (Denmark)

    Madsen, H.C.K.; Buchmann, K.; Mellergaard, Stig

    2000-01-01

    Association between various water quality parameters and the infection level of Trichodina jadranica in cultured eels were examined in nine recirculation farms in Denmark. Production units suffering from trichodiniasis (n = 4) had relatively high contents of organic dry matter (13-65 mg l(-1)), l...... by reducing the content of organic dry matter in the process water. (C) 2000 Elsevier Science B.V. All rights reserved......Association between various water quality parameters and the infection level of Trichodina jadranica in cultured eels were examined in nine recirculation farms in Denmark. Production units suffering from trichodiniasis (n = 4) had relatively high contents of organic dry matter (13-65 mg l(-1)), low...... concentrations of nitrate (150-500 mg NO3 l(-1)) and high pH (6.2-7.4) in the process water compared to farms without Trichodina problems (n = 5), which had a relatively low load of organic dry matter (9-16 mg l(-1)), high nitrate concentration (250-900 mg NO3 l(-1)) and a low pH (5.3-6.9). More detailed studies...

  3. Modification of essential fatty acid composition in broodstock of cultured European eel Anguilla anguilla L

    DEFF Research Database (Denmark)

    Støttrup, Josianne; Jacobsen, Charlotte; Tomkiewicz, Jonna

    2013-01-01

    Farmed eels had lower levels of arachidonic acid (20:4 n-6) (ARA) and higher ratios of eicosapentaenoic acid (20:5 n-3) (EPA):ARA compared to wild European eels collected from the Baltic Sea and southern Norwegian coast. Eels fed a formulated feed (JD) with a distribution of essential fatty acids...

  4. Pop up satellite tags impair swimming performance and energetics of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Methling, Caroline; Tudorache, Christian; Skov, Peter Vilhelm;

    2011-01-01

    Pop-up satellite archival tags (PSATs) have recently been applied in attempts to follow the oceanic spawning migration of the European eel. PSATs are quite large, and in all likelihood their hydraulic drag constitutes an additional cost during swimming, which remains to be quantified, as does...

  5. Pop up satellite tags impair swimming performance and energetics of the European eel (Anguilla anguilla).

    Science.gov (United States)

    Methling, Caroline; Tudorache, Christian; Skov, Peter V; Steffensen, John F

    2011-01-01

    Pop-up satellite archival tags (PSATs) have recently been applied in attempts to follow the oceanic spawning migration of the European eel. PSATs are quite large, and in all likelihood their hydraulic drag constitutes an additional cost during swimming, which remains to be quantified, as does the potential implication for successful migration. Silver eels (L(T) = 598.6±29 mm SD, N = 9) were subjected to swimming trials in a Steffensen-type swim tunnel at increasing speeds of 0.3-0.9 body lengths s(-1), first without and subsequently with, a scaled down PSAT dummy attached. The tag significantly increased oxygen consumption (MO(2)) during swimming and elevated minimum cost of transport (COT(min)) by 26%. Standard (SMR) and active metabolic rate (AMR) as well as metabolic scope remained unaffected, suggesting that the observed effects were caused by increased drag. Optimal swimming speed (U(opt)) was unchanged, whereas critical swimming speed (U(crit)) decreased significantly. Swimming with a PSAT altered swimming kinematics as verified by significant changes to tail beat frequency (f), body wave speed (v) and Strouhal number (St). The results demonstrate that energy expenditure, swimming performance and efficiency all are significantly affected in migrating eels with external tags.

  6. CARACTERISTIQUES BIOLOGIQUES DES CIVELLES (ANGUILLA ANGUILLA LORS DE LA TRANSITION EN ESTUAIRE.

    Directory of Open Access Journals (Sweden)

    DE CASAMAJOR M. N.

    2003-07-01

    Full Text Available Au cours de la saison de migration 1999/2000, de novembre à mars, un échantillonnage de civelles est réalisé dans le sud-ouest de la France. L'objectif de cet échantillonnage est de déterminer, à partir des caractéristiques biologiques (taille, masse, pigmentation, ADN/Poids sec, teneur en eau et otolithométrie des individus capturés en zone côtière et estuarienne les modifications des paramètres biologiques des civelles entre ces deux secteurs géographiques. Un amaigrissement des individus est observé au cours de la traversée de l'estuaire en décembre ce qui n'est pas visible en février. Cependant, certains individus capturés en mer présentent une marque de transition en estuaire surtout en février. Le développement de la pigmentation suit les mêmes tendances que le développement des otolithes sauf pour les civelles au stade VB. La définition du type d'otolithe est un indicateur plus précis que le développement pigmentaire pour déterminer le développement physiologique des individus. Les mesures des distances des différentes structures inscrites sur l'otolithe reflètent un passé larvaire similaire. Seul le rayon total de l'otolithe diffère entre les civelles capturées en mer et en estuaire en raison de la croissance de l'otolithe pendant la phase de transition. Il apparaît à partir des données biochimiques, otolithométriques et pigmentaires un mélange important des flux de civelles en février.

  7. Pop up satellite tags impair swimming performance and energetics of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Methling, Caroline; Tudorache, Christian; Skov, Peter Vilhelm

    2011-01-01

    Pop-up satellite archival tags (PSATs) have recently been applied in attempts to follow the oceanic spawning migration of the European eel. PSATs are quite large, and in all likelihood their hydraulic drag constitutes an additional cost during swimming, which remains to be quantified, as does...... the potential implication for successful migration. Silver eels (L(T)=598.6 +/- 29 mm SD, N = 9) were subjected to swimming trials in a Steffensen-type swim tunnel at increasing speeds of 0.3-0.9 body lengths s(-1), first without and subsequently with, a scaled down PSAT dummy attached. The tag significantly...... increased oxygen consumption (MO(2)) during swimming and elevated minimum cost of transport (COT(min)) by 26 Standard (SMR) and active metabolic rate (AMR) as well as metabolic scope remained unaffected, suggesting that the observed effects were caused by increased drag. Optimal swimming speed (U...

  8. Treatment of trichodiniasis in eel ( Anguilla anguilla ) reared in recirculation systems in Denmark : alternatives to formaldehyde

    DEFF Research Database (Denmark)

    Madsen, H.C.K.; Buchmann, Kurt; Mellergaard, Stig

    2000-01-01

    parasiticidal effect: acriflavin (25 ppm), bithionol (0.1 ppm), chloramine T (50 ppm), Detarox AP(R) (45 ppm), malachite green (1 ppm), raw garlic (200 ppm), potassium permanganate (20 ppm) and Virkon PF(R) vet. (20 ppm). Preliminary screening revealed that the anthelmintic, bithionol, and the decomposable...

  9. Evaluation of methods to determine sperm density for the european eel, anguilla anguilla

    DEFF Research Database (Denmark)

    Sørensen, Sune Riis; Gallego, V.; Pérez, L.;

    2013-01-01

    , computer-assisted sperm analysis (CASA) and flow cytometry (FCM), using Neubauer Improved haemocytometer as benchmark. Initially, relationships between spermatocrit, haemocytometer counts and sperm motility were analysed, as well as the effect of sperm dilution on haemocytometer counts. Furthermore...

  10. Recapture rate, growth and sex of stocked cultured eels Anguilla anguilla (L.)

    DEFF Research Database (Denmark)

    Pedersen, Michael Ingemann

    1998-01-01

    A total of 84,791 Alcian blue marked eels, size range 15 - 33 cm, were released in a lake, a fjord and an open coastal area. Recaptures were made by fishermen up to 4 years following release. Recaptures were most successful at the freshwater lake where 12.6% were recaptured, 2.7% in the fjord and 0...

  11. Temperature effects on gene expression and morphological development of European eel, Anguilla anguilla larvae

    DEFF Research Database (Denmark)

    Politis, Sebastian Nikitas; Mazurais, David; Servili, Arianna

    2017-01-01

    °C as the optimal temperature for offspring of European eel. Furthermore, our results suggest that the still enigmatic early life history stages of European eel may inhabit the deeper layer of the Sargasso Sea and indicate vulnerability of this critically endangered species to increasing ocean...

  12. 日本鳗鲡体表溃疡病病原菌的分离、鉴定及单克隆抗体制备%Isolation and identification of bacteriosis pathogen from Anguilla japonica ulceration of skin and preparation of its monoclonal antibody

    Institute of Scientific and Technical Information of China (English)

    樊海平; 吴斌; 曾占壮; 钟全福; 张新艳; 辛志明; 林煜; 严乾临

    2009-01-01

    从日本鳗鲡(Anguilla japonica)体表溃疡病的肝脏分离到一株优势细菌JS70322NA,经人工感染证实为引起日本鳗鲡体表溃疡病的病原菌.通过形态学观察、API 20E细菌鉴定试剂盒鉴定、生理生化试验和16S rRNA特异性基因分析,鉴定该菌为嗜水气单胞菌(Aeromonas hydrophila).JS70322NA为典型的β-溶血,血清型为O∶9.以甲醛灭活的JS70322NA为抗原免疫Balb/c小鼠,利用淋巴细胞杂交瘤技术,制备出3株抗嗜水气单胞菌的单克隆抗体,分别命名为:1A5、1B8、1F3;其腹水效价分别达1.0×10-6、1.0×10-5、1.0×10-6;细胞亚型分别为IgG2a、IgM、Ig2a;3株单克隆抗体与温和气单胞菌(Aeromonas sobria)、豚鼠气单胞菌(Aeromonas caviae)、鳗弧菌(Vibrio anguillarum)等6种水产常见致病菌无交叉反应,特异强,可应用于日本鳗鲡嗜水气单胞菌特异性检测.

  13. PCB contamination in fish community from the Gironde Estuary (France): blast from the past.

    Science.gov (United States)

    Bodin, N; Tapie, N; Le Ménach, K; Chassot, E; Elie, P; Rochard, E; Budzinski, H

    2014-03-01

    The contamination of the Gironde Estuary, southwest of France, by polychlorinated biphenyls (PCBs) was assessed using six fish of high ecological and economic importance as bioindicator species. The concentrations of 21 PCB congeners and total fat contents were determined in the muscle and liver of eels (Anguilla anguilla), seabass (Dicentrarchus labrax), flounders (Platichthys flesus), meagres (Argyrosomus regius), mullets (Liza ramada), and soles (Solea vulgaris). In addition, information regarding the trophic ecology of the studied fish was obtained through the analysis of carbon and nitrogen stable isotopes (i.e., δ(13)C and δ(15)N) in muscle. Results revealed high PCB concentrations in fish compared to monitored European estuaries. The muscle of eels was by far the most contaminated fish flesh (Σ7PCBs=1000±440 ng g(-1) on a dry weight basis), while the higher PCB concentrations in liver were measured in flounder (Σ7PCBs=2040±1160 ng g(-1) d.w.). A quantile regression approach allowed to investigate the fate of PCBs in the Gironde estuarine fish assemblage, and revealed a general process of trophic magnification. Finally, most of the analysed fish presented PCB concentrations in muscle meat above the current European maximum limits for sea products, while the derived "Toxic Equivalent Quantity" (TEQ) revealed human health concerns only for high-fat fish consumption. Copyright © 2014. Published by Elsevier Ltd.

  14. An updated checklist of poisonous fishes of Turkish Aegean Sea

    Directory of Open Access Journals (Sweden)

    Bahar Bayhan

    2015-07-01

    Full Text Available The current status of marine poisonous fish species ranging in the Aegean Sea coastline in Turkey were introduced. Turkey is a peninsula surrounded by seas with different ecological features on three sides. The total length of shoreline is 8 333 km including the islands. The total number of fish species in Turkish seas is 512, of which 449 live in the Aegean Sea followed by the Mediterranean Sea (441 species, the Marmara Sea (257 species and the Black Sea (154species. On the Aegean Sea coasts, the richest sea regarding fish diversity, the number of poisonous fish species is also high. This mini-review revealed 51 poisonous fish species belonging to 14 families in the Turkish Aegean Sea. On the Aegean Sea coasts poisonous fish species can be categorized into three groups: (i Fish that contain venomous spines on the tail or on the operculum (ii Fish that carry poisonous bite and (iii Fish having poisonous flesh or liver. Poisoning fish that contain venomous spines on the tail or on the operculum mostly are dangerous because of their poisonous thorns whereas the passive poisonous fish species poison when they are eaten. These toxins can cause morbidity and rarely, mortality in humans. Apart from these, swallowing the blood of species such as European eel Anguilla anguilla and European conger Conger conger might also cause poisoning. Besides, as there has been an invasion of puffer fish especially on the Turkish Mediterranean and Aegean coasts in recent years, there is a danger in question. Thus, it is very important to particularly draw attention to these fish on the Turkish coasts.

  15. Freshwater fish of the Wilderness National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    1999-01-01

    Full Text Available The study aimed to determine the distribution and relative abundance of freshwater fish in the Wilderness National Park. Fish assemblages in the Touw and Duiwe rivers were sampled in 1997 and 1998, with a total of 327 fish from nine species recorded. Indigenous species included two freshwater species (Pseudobarbus afer, Sandelia capensis, two catadromous species (Anguilla mossambicus, Myxus capensis, and two estuarine species (Monodactylusfalciformis, Caffrogobius multifasciatus. Three of the nine recorded species were alien (Micropterus dolomieu, Micropterus salmoides, Gambusia affinis, with the Micropterus spp., in particular, likely to have a substantial negative influence on indigenous species. A further one indigenous species, two translocated indigenous species, and five estuarine species could potentially be recorded in these rivers. River catchment management actions to restore perennial flow to the Duiwe River, to prevent the attenuation of floods, and to prevent further establishment and spread of alien and translocated biota are required to conserve indigenous fish assemblages.

  16. Freshwater fishes of Bontebok National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2001-08-01

    Full Text Available Fish assemblages were sampled at six sites in the Breede River in the Bontebok National Park during 1999 and 2000. A total of 380 fish from 12 species was recorded. Indigenous fish collected included one freshwater species (Barbus andrewi, two catodromous species (Anguilla mossambica, Myxus capensis. and three estuarine species (Gilchris- tella aestuaria, Monodactylusfalciformis, Mugil cephalus. Four of the species recorded were aliens (Tinea tinea, Lepomis macrochirus, Micropterus salmoides, Micropterus dolomieu and two species translocated from other South African rivers (Tilapia sparrmanii, Clarias gariepinus. A further two indigenous species (Sandelia capensis, Pseudobarbus biirchelli could potentially occur within the park, though the high abundance of alien predators means that there is little chance for recolonisation from tributaries higher in the Breede River system. There is little opportunity to meaningfully conserve most indigenous freshwater fish in Bontebok National Park.

  17. PCBs in the fish assemblage of a southern European estuary

    Science.gov (United States)

    Baptista, Joana; Pato, Pedro; Pereira, Eduarda; Duarte, Armando C.; Pardal, Miguel A.

    2013-02-01

    The Mondego estuary fish assemblage was studied for the accumulation of PCBs. Three sampling stations were visited along an estuarine salinity gradient, and, in total, 15 species were collected. Analysis of PCBs revealed no significant differences among the sampling stations, although differences were observed among the fish assemblages. Fish assemblages could be divided into three groups. The first group comprised those with higher concentration (more than 10 ng g- 1, dw), included the species Gobius niger, Sardina pilchardus, Anguilla anguilla, Pomatoschistus microps, Chelidonichthys lucerna and Liza ramada; the second group with medium concentration (5-10 ng g- 1, dw), included the species Pomatoschistus minutus, Dicentrarchus labrax, Atherina presbyter, Chelon labrosus, Diplodus vulgaris, Platichthys flesus and Cilata mustela; and a third group with low concentration (less than 5 ng g- 1, dw), included the species Solea solea and Callionymus lyra. A positive correlation was found between lipid content and PCB concentrations. To evaluate the influence of the residence time of species on the accumulation of PCBs, species were divided into two groups: species that spend more than 3 years in the estuary, and species that spend less than 3 years in the estuary. Species that spend more than 3 years in the estuary presented higher concentrations than species that spend less than 3 years in the estuary. CBs 138 and 153 had higher concentration, and tended to increase with time spent in the estuary.

  18. Fish peripheral blood mononuclear cells preparation for future monitoring applications.

    Science.gov (United States)

    Pierrard, Marie-Aline; Roland, Kathleen; Kestemont, Patrick; Dieu, Marc; Raes, Martine; Silvestre, Frédéric

    2012-07-15

    Fish species possess many specific characteristics that support their use in ecotoxicology. Widely used in clinical research, peripheral blood mononuclear cells (PBMCs) can reasonably be exploited as relevant target cells in the assessment of environmental chemical toxicity. The current article focuses on the methods necessary to isolate, characterize, and culture fish PBMCs. These procedures were successfully applied on an endangered species, the European eel (Anguilla anguilla L.), and on an economically important and worldwide exported species, the Asian catfish (Pangasianodon hypophthalmus S.). Proteomic approaches can be useful to screen xenobiotic exposure at the protein expression level, giving the opportunity to develop early warning signals thanks to molecular signatures of toxicity. To date, a major limitation of proteomic analyses is that most protein expression profiles often reveal the same predominant and frequently differentially expressed families of proteins regardless of the experimental stressing conditions. The current study describes a methodology to get a postnuclear fraction of high quality isolated from fish PBMCs in order to perform subsequent subproteomic analyses. Applied on samples from eel, the subproteomic analysis (two-dimensional differential in-gel electrophoresis) allowed the identification by liquid chromatography-tandem mass spectrometry and searches in the full NCBInr (National Center for Biotechnology Information nonredundant) database of 66 proteins representing 36 different proteins validated through Peptide and Protein Prophet of Scaffold software.

  19. Pharmacokinetics and Residues of Albendazole and Its Metabolites in European Eels(Anguilla anguilla)%阿苯达唑及其代谢物在欧洲鳗鲡体内的药代动力学及残留研究

    Institute of Scientific and Technical Information of China (English)

    廖碧钗

    2012-01-01

    在试验水温(25±2)℃条件下,按2 mg/kg的浓度给欧洲鳗鲡浸浴阿苯达唑36 h,高效液相色谱法测定血浆和肌肉组织中的药物浓度,研究阿苯达唑在欧洲鳗鲡体内的代谢及消除规律。结果显示:阿苯达唑和阿苯达唑亚砜的血药时间数据符合一级吸收二室开放模型,阿苯达唑砜符合一级吸收一室开放模型;其消除半衰期分别为34.15h、99.34h、46.00 h,最大血药浓度分别为3.887、6.830、1.738 mg/L,达峰时间分别为7.27h1、8.00h、40.67h,药时曲线下面积(AUC)分别为129.71、921.95、236.58 mg.h/L。选取可食组织肌肉作为残留检测的靶组织,以农业部残留限量100μg/kg为最高残留限量,在本试验条件下,建议休药期不低于23 d。%In order to study the metabolism and elimination of albendazole and its metabolites European eels(Anguilla anguilla) were immersed with albendazole at a dose of 2mg/kg for 36h and kept at water temperature of 25±2℃.The results showed that plasma concentration-time data of albendazole and albendazole sulphoxide were best fitted to a two-compartmental open model.Albendazole sulphone was best fitted to one-compartmental open model.Elimination half-life of albendazole,albendazole sulphoxide and albendazole sulphone were 34.15,99.34,46.00h,respectively.The maximal plasma concentrations were 3.887,6.830,1.738 mg/L,respectively.The time to peak concentrations were 7.27,18.00,40.67 h,respectively.Area under the plasma drug concentration-time curves were 129.71,921.95,236.58 mg.h/L,respectively.As an edible tissue,muscle was selected as target tissue in this experiment.The maximum residue limit(MRL) of Ministry of Agriculture is 100μg/kg in muscle,the withdrawal time should not be less than 23 days under this experiment condition.

  20. Fish welfare assurance system: initial steps to set up an effective tool to safeguard and monitor farmed fish welfare at a company level.

    Science.gov (United States)

    van de Vis, J W; Poelman, M; Lambooij, E; Bégout, M-L; Pilarczyk, M

    2012-02-01

    The objective was to take a first step in the development of a process-oriented quality assurance (QA) system for monitoring and safeguarding of fish welfare at a company level. A process-oriented approach is focused on preventing hazards and involves establishment of critical steps in a process that requires careful control. The seven principles of the Hazard Analysis Critical Control Points (HACCP) concept were used as a framework to establish the QA system. HACCP is an internationally agreed approach for management of food safety, which was adapted for the purpose of safeguarding and monitoring the welfare of farmed fish. As the main focus of this QA system is farmed fish welfare assurance at a company level, it was named Fish Welfare Assurance System (FWAS). In this paper we present the initial steps of setting up FWAS for on growing of sea bass (Dicentrarchus labrax), carp (Cyprinus carpio) and European eel (Anguilla anguilla). Four major hazards were selected, which were fish species dependent. Critical Control Points (CCPs) that need to be controlled to minimize or avoid the four hazards are presented. For FWAS, monitoring of CCPs at a farm level is essential. For monitoring purposes, Operational Welfare Indicators (OWIs) are needed to establish whether critical biotic, abiotic, managerial and environmental factors are controlled. For the OWIs we present critical limits/target values. A critical limit is the maximum or minimum value to which a factor must be controlled at a critical control point to prevent, eliminate or reduce a hazard to an acceptable level. For managerial factors target levels are more appropriate than critical limits. Regarding the international trade of farmed fish products, we propose that FWAS needs to be standardized in aquaculture chains. For this standardization a consensus on the concept of fish welfare, methods to assess welfare objectively and knowledge on the needs of farmed fish are required.

  1. Radionuclides ((210)Po and (210)Pb) and Some Heavy Metals in Fish and Sediments in Lake Bafa, Turkey, and the Contribution of (210)Po to the Radiation Dose.

    Science.gov (United States)

    Manav, Ramazan; Uğur Görgün, Aysun; Filizok, Işık

    2016-11-09

    The pollution level of Lake Bafa was investigated by collecting fish samples {Dicentrarchus labrax (sea bass), Liza ramada (mullet) and Anguilla anguilla (eel)}, surface sediment, and core samples. In all these samples, (210)Po and (210)Pb concentrations were estimated, and total annual dose rates were obtained for each species. Some heavy metal (Cr, Ni, Pb, Cd, Mn, Fe, and Zn) concentration levels were obtained for the fish and a core sample. The sediment mass accumulation rate was found to be 3.27 g·m(-2)·day(-1) (0.119 g·cm(-2)·y(-1)) from a core sample. The heavy metal concentrations in the vertical profile of samples from the core were also observed. The measured concentration of Zn, Pb, Cd, and Cr were between the ERL (effects range low) and ERM (effects range median) limits, while Ni concentrations were higher than the ERM limit. The observed concentrations of Cd, Pb, and Zn in fish samples did not exceed the limits in accordance with Turkish Food Regulations. Further, the maximum effective dose equivalent of (210)Po in the area was found to be 1.169 µSv·y(-1).

  2. Radionuclides (210Po and 210Pb) and Some Heavy Metals in Fish and Sediments in Lake Bafa, Turkey, and the Contribution of 210Po to the Radiation Dose

    Science.gov (United States)

    Manav, Ramazan; Uğur Görgün, Aysun; Filizok, Işık

    2016-01-01

    The pollution level of Lake Bafa was investigated by collecting fish samples {Dicentrarchus labrax (sea bass), Liza ramada (mullet) and Anguilla anguilla (eel)}, surface sediment, and core samples. In all these samples, 210Po and 210Pb concentrations were estimated, and total annual dose rates were obtained for each species. Some heavy metal (Cr, Ni, Pb, Cd, Mn, Fe, and Zn) concentration levels were obtained for the fish and a core sample. The sediment mass accumulation rate was found to be 3.27 g·m−2·day−1 (0.119 g·cm−2·y−1) from a core sample. The heavy metal concentrations in the vertical profile of samples from the core were also observed. The measured concentration of Zn, Pb, Cd, and Cr were between the ERL (effects range low) and ERM (effects range median) limits, while Ni concentrations were higher than the ERM limit. The observed concentrations of Cd, Pb, and Zn in fish samples did not exceed the limits in accordance with Turkish Food Regulations. Further, the maximum effective dose equivalent of 210Po in the area was found to be 1.169 µSv·y−1. PMID:27834886

  3. Radionuclides (210Po and 210Pb and Some Heavy Metals in Fish and Sediments in Lake Bafa, Turkey, and the Contribution of 210Po to the Radiation Dose

    Directory of Open Access Journals (Sweden)

    Ramazan Manav

    2016-11-01

    Full Text Available The pollution level of Lake Bafa was investigated by collecting fish samples {Dicentrarchus labrax (sea bass, Liza ramada (mullet and Anguilla anguilla (eel}, surface sediment, and core samples. In all these samples, 210Po and 210Pb concentrations were estimated, and total annual dose rates were obtained for each species. Some heavy metal (Cr, Ni, Pb, Cd, Mn, Fe, and Zn concentration levels were obtained for the fish and a core sample. The sediment mass accumulation rate was found to be 3.27 g·m−2·day−1 (0.119 g·cm−2·y−1 from a core sample. The heavy metal concentrations in the vertical profile of samples from the core were also observed. The measured concentration of Zn, Pb, Cd, and Cr were between the ERL (effects range low and ERM (effects range median limits, while Ni concentrations were higher than the ERM limit. The observed concentrations of Cd, Pb, and Zn in fish samples did not exceed the limits in accordance with Turkish Food Regulations. Further, the maximum effective dose equivalent of 210Po in the area was found to be 1.169 µSv·y−1.

  4. Time trends in fish populations in metropolitan France: insights from national monitoring data.

    Science.gov (United States)

    Poulet, N; Beaulaton, L; Dembski, S

    2011-12-01

    Using the electrofishing database of the French National Agency for Water and Aquatic Environment (Onema), the time trends of 48 freshwater fish taxa at 590 sites monitored for at least 8 years from 1990 to 2009 were investigated. The results demonstrated that species richness increased steadily from the beginning of the monitoring period. This is congruent with the finding that the number of species displaying a significant increase in spatial distribution or abundance was greater than those showing a significant decrease. Some species, however, had declined both in occurrence and abundance, e.g. tench Tinca tinca, common bream Abramis brama, brown trout Salmo trutta and European eel Anguilla anguilla. The species showing the most spectacular colonization were non-native, e.g. topmouth gudgeon Pseudorasbora parva, wels catfish Silurus glanis and asp Aspius aspius. The time trends in population density were related to the maximal body size, habitat requirement, occurrence and abundance and the status (i.e. native or exotic) but not to the spawning temperature.

  5. Historical freshwater fish ecology: a long-term view of distribution changes and biological invasions

    Directory of Open Access Journals (Sweden)

    Miguel Clavero

    2015-12-01

    Full Text Available Past processes and events may have an important influence on contemporaneous ecological patterns, including current human impacts on landscapes and organisms. In spite of that, most of the ecological knowledge has been built upon short-term studies, which very rarely exceed one decade. Ecology and Conservation Biology have an important lack of historical approaches, a deficiency that may become a hindrance for the management of natural systems. In this talk I will present examples of how historical information on the distribution of freshwater fish and other aquatic organisms can be used to address ecological questions. Most analyses are based on two important Spanish historical written sources: the Relaciones de Felipe II (16th century and the Madoz Dictionary (19th century. The examples considered include the European eel (Anguilla anguilla, the brown trout (Salmo trutta, the common carp (Cyprinus carpio and the white clawed crayfish (Austropotamobius italicus, among other species, as well as questions related to biological invasions, habitat loss and the impacts of global warming. The outputs of ecological research based on historical data often become useful tools for present-day biodiversity conservation planning and actions.

  6. Effect of the pesticide Deltamethrin on the Mauthner cells of Lake Balaton fish.

    Science.gov (United States)

    Csillik, B; Fazakas, J; Nemcsók, J; Knyihár-Csillik, E

    2000-06-01

    Deltamethrin, a synthetic pesticide [(S)alpha-cyano-3-phenoxybenzyl-(1R)-cis-3-(2.2-dibromovinyl)-2,2-dim ethylcyclopropane-carboxylate] used for extermination of mosquitoes on the shores of lake Balaton, has been found to induce severe impairments of the nervous system of several Lake Balaton fish, such as carp (Cyprinus carpio), goldfish (Carassius auratus gibelis Bloch), eel (Anguilla anguilla) and wels (Silurus glanis). It has been shown that Deltamethrin, in a concentration of 1 microgram/liter in the aquarium water, inhibits acetylcholinesterase enzyme activity of the giant Mauthner's nerve cells as well as of the axon terminals synapsing with these cells. Even more importantly, however, Deltamethrin in a concentration of 10 micrograms per liter, induces blockade of the expression of choline acetyltransferase in the bulbous axon terminals synapsing with the lateral dendrites of the Mauthner cells. Since, under normal conditions, the function of the Mauthner cells is to co-ordinate the C-start reaction, by which fish rapidly leave sites of nociceptive stimulation, it stands for reason to assume that Deltamethrin intoxicated fish may be prone to become victims of various factors which endanger survival of the individual. During the last decade, waves of fish deaths were observed in Lake Balaton, which is the largest fresh-water lake in Europe. Fish death coincided with airborne mosquito-killing campaigns. Results of the enzyme- and immunohistochemical studies described in this paper, together with the deleterious effects of Deltamethrin to the enteric nervous system of fish which has been reported earlier (Lang et al., 1997) suggest that fish death might be caused by the indiscriminate use of Deltamethrin airborne spray in the mosquito-extermination campaigns.

  7. Development and validation of a range of endogenous controls to support the implementation of practical Taqman real-time PCR-based surveillance for fish diseases within aquaculture.

    Science.gov (United States)

    Bland, F; McIntosh, R; Bain, N; Snow, M

    2012-06-01

    The use of Taqman real-time PCR-based technology has recently become more frequent in the detection of pathogens in the aquaculture industry. This interest has necessitated the development of robust and reliable pathogen-detection assays. The development of a range of endogenous control assays to be run alongside these diagnostic assays works to further increase confidence in the latter. This study describes the design of a range of endogenous control assays based on the elongation factor 1-α (EF1-α) gene specific to a range of fish species including Atlantic salmon, Salmo salar; rainbow trout, Oncorhynchus mykiss; brown trout, Salmo trutta; cod, Gadus morhua; haddock, Melanogrammus aeglefinus; saithe, Pollachius virens; whiting, Merlangius merlangus; Norway pout, Trisopterus esmarkii; carp (family Cyprinidae), roach, Rutilus rutilus; European eel, Anguilla anguilla; and herring, Clupea harengus, as well as a number of fish cell lines. Evidence is provided of the validation of these assays for specific species, a range of tissue types and cell lines as well as an example of the potential uses of these assays.

  8. Effects of temperature on the nitric oxide-dependent modulation of the Frank-Starling mechanism: the fish heart as a case study.

    Science.gov (United States)

    Amelio, D; Garofalo, F; Capria, C; Tota, B; Imbrogno, S

    2013-02-01

    The Frank-Starling law is a fundamental property of the vertebrate myocardium which allows, when the end-diastolic volume increases, that the consequent stretch of the myocardial fibers generates a more forceful contraction. It has been shown that in the eel (Anguilla anguilla) heart, nitric oxide (NO) exerts a direct myocardial relaxant effect, increasing the sensitivity of the Frank-Starling response (Garofalo et al., 2009). With the use of isolated working heart preparations, this study investigated the relationship between NO modulation of Frank-Starling response and temperature challenges in the eel. The results showed that while, in long-term acclimated fish (spring animals perfused at 20 °C and winter animals perfused at 10 °C) the inhibition of NO production by L-N5 (1-iminoethyl)ornithine (L-NIO) significantly reduced the Frank-Starling response, under thermal shock conditions (spring animals perfused at 10 or 15 °C and winter animals perfused at 15 or 20 °C) L-NIO treatment resulted without effect. Western blotting analysis revealed a decrease of peNOS and pAkt expressions in samples subjected to thermal shock. Moreover, an increase in Hsp90 protein levels was observed under heat thermal stress. Together, these data suggest that the NO synthase/NO-dependent modulation of the Frank-Starling mechanism in fish is sensitive to thermal stress.

  9. Interactive effects of dietary composition and hormonal treatment on reproductive development of cultured female European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    da Silva, Filipa; Støttrup, Josianne Gatt; Kjørsvik, Elin

    2016-01-01

    Farmed female eels were fed two experimental diets with similar proximate composition but different n-3 polyunsaturated fatty acid (PUFA) levels. Both diets had similar levels of arachidonic acid (ARA), while levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in one diet were...

  10. An outbreak of Shewanella putrefaciens group in wild eels Anguilla anguilla L. favoured by hypoxic aquatic environments.

    Science.gov (United States)

    Esteve, C; Merchán, R; Alcaide, E

    2017-07-01

    Microbiological analyses were conducted on wild eels from the L'Albufera Lake (Spain). A total of 174 individuals were collected in two surveys (i.e. year 2008 and autumn-winter 2014) among those caught by local fishermen into the lagoon. The prevalence of Shewanella putrefaciens group was 1.7% in 2008 and rose above 32% in 2014. It was due to an outbreak of shewanellosis that presented a morbidity rate of 64%. S. putrefaciens group strains were isolated as pure cultures from the sick eels that showed white ulcers surrounded by a reddish inflammation, damage of the mouth, extensive skin discoloration, exophthalmia, ascites and bad odour. The S. putrefaciens group was recovered from freshwater samples taken at the L'Albufera system, along autumn-winter 2015. Its counts significantly increased in freshwater parallel to hypoxia and temperature rising. Shewanellae strains were identified as S. putrefaciens and S. xiamenensis by 16S rRNA gene sequencing. These isolates recovered from sick eels or freshwater were virulent for European eel by IP challenge (LD50 10(6)  CFU g(-1) body weight). They also caused 30-38% cumulative mortality, in European eels challenged by a 2-h bath (10(7)  CFU mL(-1) ). These results suggest that shewanellosis could be transmitted through water highlighting the fact that hypoxic conditions increase this bacterium levels in water. © 2016 John Wiley & Sons Ltd.

  11. In vitro aerobic and anaerobic muscle capacities in the European eel, Anguilla anguilla: effects of a swimming session.

    Science.gov (United States)

    Sébert, Philippe; Mortelette, Hélène; Nicolas, Jonathan; Amérand, Aline; Belhomme, Marc; Moisan, Christine

    2011-05-31

    In order to have a general view of metabolic requirements during swimming, in vitro aerobic and anaerobic fluxes were measured in red and white muscles from silver eels and yellow eels which differ in activity levels and nutritional states. These measurements were performed in control eels and after a 4 day swimming session (70% U(crit) in yellow eels, 80% U(crit) in silver eels). A swimming session significantly increases U(crit) from 12% to 18%, depending on the stage, with a significantly higher in vitro energy cost during the yellow stage at the muscle level. In vitro, the swimming session brings about a gain in anaerobic capacities rather than in aerobic ones. Some in vivo hypotheses are proposed.

  12. The temperature challenges on cardiac performance in winter-quiescent and migration-stage eels Anguilla anguilla

    DEFF Research Database (Denmark)

    Methling, C.; Steffensen, J. F.; Skov, Peter Vilhelm

    2012-01-01

    , and following acute ± 10 °C temperature changes. The time-course of contraction, and thus maximal attainable heart rates, was greatly influenced by working temperature, but was independent of acclimation history. The absolute force of contraction and power production (i.e. the product of force and stimulation......The present study was undertaken to examine cardiac responses to some of the temperature challenges that eels encounter in their natural environment. The contractile properties of ventricular muscle was studied on electrically paced tissue strips after long term acclimation at 0 °C, 10 °C, or 20 °C...... frequency) was significantly influenced by acute temperature decrease from 20 °C to 10 °C. The role of adrenaline as a modulator of contraction force, power production, rates of contraction and relaxation, and minimum time in contraction was assessed. Increased adrenergic tonus elicited a positive inotropic...

  13. Influence of temperature regime on endocrine parameters and vitellogenesis during experimental maturation of European eel (Anguilla anguilla) females

    NARCIS (Netherlands)

    Perez, L.; Penaranda, D.S.; Dufour, S.; Baloche, S.; Palstra, A.P.; Thillart, G.E.E.J.M.; Asturiano, J.F.

    2011-01-01

    We examined the effect of temperature in European silver eels during their maturation induced by injections of carp pituitary extract on endocrine parameters: pituitary fshß and lhß expression, plasma 17ß-estradiol (E2) and vitellogenin, estrogen receptor 1 (esr1), and vitellogenin 2 (vtg2) expressi

  14. Gill lipid metabolism and unidirectional Na+ flux in the European eel (Anguilla anguilla) after transfer to dilute media

    DEFF Research Database (Denmark)

    Hansen, H.J.M.; Grosell, M.; Rosenkilde, P.

    1999-01-01

    positive linear correlation of percentage (14C) wax alcohols with log [22Na efflux]. Based on the observed parallel between Naf flux and gill lipid metabolism, it is suggested that the eel reacts at first to a loss of Na+ by synthesizing wax alcohols that can tighten the gill membrane. (C) 1999 Elsevier......+ uptake rate was 12 mu mol kg(-1) h(-1), i.e., the general picture in DW was a net Na+ loss. In another similar experiment, groups of three FW-adapted eels were incubated in vivo for up to 24 h with (C-14) acetate added as lipid precursor to the ambient water. Incubation in FW showed about 20......% of the total C-14-activity incorporated into gill lipids as (C-14) wax alcohols (WA; octadecanol and eicosanol). This percentage went up to 50% shortly after transfer to DW and came down again to about 20% after 2 weeks in DW. Single eels labelled with Na-22 in the plasma showed a statistically significant...

  15. CONTAMINATION PAR ANGUILLICOLA CRASSUS DE CINQ POPULATIONS D’ANGUILLES (ANGUILLA ANGUILLA DU LITTORAL DE BRETAGNE SUD (FRANCE

    Directory of Open Access Journals (Sweden)

    SAUVAGET B.

    2003-07-01

    Full Text Available Les anguilles prélevées dans cinq zones de salinité variable du littoral de Bretagne sud, ont été examinées pour leur infestation présente et passée par le parasite Anguillicola crassus (Nematoda, dracunculoidea. Les anguilles vivant dans des milieux peu salés au contact de la zone dulçaquicole sont très contaminées avec des prévalences supérieures à 90%, dont 61% concernent des prévalences présentes. Par contre, celles vivant dans des conditions estuariennes (Golfe du Morbihan sont relativement épargnées avec des prévalences de l’ordre de 15%, dont en moyenne moins de la moitié concernent des prévalences présentes. La salinité des baies et des estuaires semble donc pouvoir préserver de la contamination les populations d’anguilles côtières dont la gestion devient un enjeu prioritaire pour le stock d’anguilles.

  16. Effects of PCBs on the energy cost of migration and blood parameters of European silver eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Ginneken, van V.; Palstra, A.P.; Nieveen, M.; Berg, van den J.H.J.; Flik, G.; Spanings, F.A.; Niemantsverdriet, P.; Thillart, van den G.; Murk, A.J.

    2009-01-01

    Organochlorine compounds were widely used after the Second World War because they were cheap to produce and useful for many purposes, such as in agriculture for insecticides, in public health to control disease insect vectors and in industry (Pelletier et al. 2002). It is estimated that 16¿30% of th

  17. Swimming physiology of European silver eels (Anguilla anguilla L.): energetic costs and effects on sexual maturation and reproduction

    Science.gov (United States)

    van den Thillart, Guido E. E. J. M.

    2010-01-01

    The European eel migrates 5,000–6,000 km to the Sargasso Sea to reproduce. Because they venture into the ocean in a pre-pubertal state and reproduce after swimming for months, a strong interaction between swimming and sexual maturation is expected. Many swimming trials have been performed in 22 swim tunnels to elucidate their performance and the impact on maturation. European eels are able to swim long distances at a cost of 10–12 mg fat/km which is 4–6 times more efficient than salmonids. The total energy costs of reproduction correspond to 67% of the fat stores. During long distance swimming, the body composition stays the same showing that energy consumption calculations cannot be based on fat alone but need to be compensated for protein oxidation. The optimal swimming speed is 0.61–0.67 m s−1, which is ~60% higher than the generally assumed cruise speed of 0.4 m s−1 and implies that female eels may reach the Sargasso Sea within 3.5 months instead of the assumed 6 months. Swimming trials showed lipid deposition and oocyte growth, which are the first steps of sexual maturation. To investigate effects of oceanic migration on maturation, we simulated group-wise migration in a large swim-gutter with seawater. These trials showed suppressed gonadotropin expression and vitellogenesis in females, while in contrast continued sexual maturation was observed in silver males. The induction of lipid deposition in the oocytes and the inhibition of vitellogenesis by swimming in females suggest a natural sequence of events quite different from artificial maturation protocols. PMID:20390348

  18. MACROPARASITE COMMUNITY AND ASYMMETRY OF THE YELLOW EEL ANGUILLA ANGUILLA IN SALSES-LEUCATE LAGOON, SOUTHERN FRANCE

    Directory of Open Access Journals (Sweden)

    FAZIO G.

    2005-10-01

    Full Text Available European eel parasites, in particular invasive species, are suspected to have a strong influence on the population dynamics of their host. The aim of this work was to study the relationship between parasitic fauna of yellow eels caught at Salses-Leucate lagoon and the fluctuating asymmetry (FA of some functional bilateral traits: pectoral fins, eyes and otoliths. Epidemiological distance matrices and FA distance matrices were calculated on the basis of the Euclidian distances between each pair of eel and were then compared with a Mantel test in order to establish if there was a relationship between parasitism and FA. Our results revealed different morphological characteristics between eels caught at different dates; only otoliths were found asymmetric. The parasite richness was of 10 species, 1 Nematoda, 1 Acanthocephala, 1 Monogenea and 7 Digenea. We failed to find a significant relationship between asymmetry and parasitism, except for parasites found in the stomach. We discussed the results in the light of the eel life cycle, the specificity of parasite - eel systems and the impact of parasites on the host physiology.

  19. Heavy metal distribution in tissues of six fish species included in human diet, inhabiting freshwaters of the Nature Park "Hutovo Blato" (Bosnia and Herzegovina).

    Science.gov (United States)

    Has-Schön, Elizabeta; Bogut, Ivan; Rajković, Valentina; Bogut, Stjepan; Cacić, Milan; Horvatić, Janja

    2008-01-01

    The aim of the study was to quantify heavy metal (mercury, lead, cadmium, and arsenic) concentration in tissues (muscles, liver, kidney, gills, and gonads) of six fish species (carp: Cyprinus carpio, tench: Tinca tinca, pumpkinseed: Lepomis gibosus, prussian carp: Carassius auratus gibelio, hasselquist: Salmo dentex, eel: Anguilla anguilla) from the freshwaters of the Nature Park Hutovo Blato, Bosnia and Herzegovina, and determine whether they are potentially harmful for human health if included in the diet. Fish were angled from the Svitava Lake in the second part of August of the year 2003, and fish tissues were stored at -18 degrees C until analysis. Heavy metal concentration was determined by atomic absorption spectrophotometry in the Veterinary Institute Brno, Czech Republic, and expressed as mg.kg(-1) of wet tissue. Concentration of mercury, lead, and arsenic in most tissues of all analyzed fish types is lower than the maximal allowed concentration (MAC) in most countries. Cadmium concentration is also low in muscles and gonads, but kidney, liver, and gill concentrations exceed MAC value in most countries. Hasselquist, an endemic type for that region, differs from other fish types in the fact that it has very low cadmium concentration in liver and kidney, but the highest concentration of arsenic in most tissues, especially muscles. In muscles and gonads of all fish types analyzed, Pb is present in higher concentration than Cd, whereas in liver, gills, and particularly kidney, the situation is opposite, suggesting diverse metabolic pathways and unequal bioaccumulation of these two metals in different fish tissues. Although the region of the Nature Park Hutovo Blato in Bosnia and Herzegovina is not an agricultural territory, the intensive agricultural activities in the neighboring regions already result in high cadmium concentration in inner organs of fish species analyzed. Therefore, fish types in the freshwaters of the Park may be included in the human diet

  20. Dioxins and dioxin-like PCBs in different fish from the river Elbe and its tributaries, Germany.

    Science.gov (United States)

    Stachel, B; Christoph, E-H; Götz, R; Herrmann, T; Krüger, F; Kühn, T; Lay, J; Löffler, J; Päpke, O; Reincke, H; Schröter-Kermani, C; Schwartz, R; Steeg, E; Stehr, D; Uhlig, S; Umlauf, G

    2007-09-05

    In a long-term program polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) as well as dioxin-like polychlorinated biphenyls (DL-PCBs) were analyzed in the muscle tissue of eels (Anguilla anguilla), bream (Abramis brama), European chub (Leuciscus cephalus) and ide (Leuciscus idus) from the river Elbe and its tributaries Mulde and Saale. The variation of the PCDD/F and DL-PCB concentrations in all fish samples is very large, whereby the DL-PCBs predominate in comparison to the PCDD/Fs. In the eels, the concentrations (pg WHO-TEQ/g ww) for the PCDD/Fs lie in the range of 0.48-22 and for the DL-PCBs between 8.5 and 59. In the whitefish, the concentration range is 0.48-12 for the PCDD/Fs and 1.2-14 for the DL-PCBs. Statistical analysis using relative congener patterns for PCDD/Fs allow spatial correlations to be examined for sub-populations of eels and whitefish. The results are compared to the maximum levels laid down in the European Commission Regulation (EC) No. 466/2001 and the action levels of the European Commission Recommendation 2006/88/EC. Eels caught directly after the major flood in August 2002 as well as eels near Hamburg (years 1996 and 1998) show high concentration peaks. Compared to the eels whitefish is less contaminated with PCDD/Fs and DL-PCBs.

  1. Spatial and temporal variation in fish community of the Ria de Aveiro estuarine lagoon (Portugal.

    Directory of Open Access Journals (Sweden)

    Eva García-Seoane

    2015-11-01

    Full Text Available Fish assemblages of Ria de Aveiro coastal lagoon (Northwest Portugal were studied from February 2012 and January 2013. Sampling were monthly conducted with a traditional beach-seine net (“chincha” at 9 sites. Multivariate approach were used in order to analyse the spatial and temporal variation in fish community. A total of 58,201 fishes, weighting 249,540 g, were identified, representing 37 taxa and 21 families. Four taxa (Atherina spp., Dicentrarchus labrax, Liza spp., and Sardina pilchardus were responsible for 94.7% and 85.4% of the total abundance, in number and weight. There were significant differences in fish community, in terms of fish number and weight, between sites and between months (ANOSIM, p<0.01. A total of 12 species appeared as characteristics of one of more sampling sites either in terms of number and weight. In both cases, D. labrax, Liza spp. and Atherina spp. were typical throughout the study area. Other species, such as Spondyliosoma cantharus appeared as typical only in the part of the lagoon more influenced by marine waters, whereas Anguilla anguilla was typical of the inner area. A total of 11 (in number or 13 (in weight species appeared as typical of at least one month of the year. Liza spp. and Atherina spp. were typical all the year round for number and weight data. In both cases, D. labrax, Diplodus spp. and S. pilchardus, appeared as a typical from spring to autumn. The number of typical species varied with the season, being maximum in May and minimum in winter. Finally, results of this work were discussed in comparison to previous studies.

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

    Science.gov (United States)

    Wyrzykowska, Barbara; Falandysz, Jerzy; Jarzyńska, Grażyna

    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 μg/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.

  3. Are DNA-damaging effects induced by herbicide formulations (Roundup® and Garlon®) in fish transient and reversible upon cessation of exposure?

    Science.gov (United States)

    Guilherme, S; Santos, M A; Gaivão, I; Pacheco, M

    2014-10-01

    Owing to the seasonality of crop cultivation and subsequent periodic/seasonal application of herbicides, their input to the aquatic systems is typically intermittent. Consequently, exposure of fish to this type of contaminants can be short and followed by a period of permanence in non-contaminated areas. Thus, the assessment of genotoxic endpoints in fish after removal of the contamination source appears as a crucial step to improve the knowledge on the dynamics of herbicide genotoxicity, as well as to determine the actual magnitude of risk posed by these agrochemicals. Therefore, the present study intended to shed light on the ability of fish to recover from the DNA damage induced by short-term exposures to the herbicide formulations Roundup(®) (glyphosate-based) and Garlon(®) (triclopyr-based) upon the exposure cessation. European eel (Anguilla anguilla) was exposed to the above commercial formulations for 3 days, and allowed to recover for 1, 7 and 14 days (post-exposure period). The comet assay was used to identify the DNA damage in blood cells during both exposure and post-exposure periods. As an attempt to clarify the DNA damaging mechanisms involved, an extra-step including the incubation of the nucleotides with DNA lesion-specific repair enzyme was added to the standard comet. The genotoxic potential of both herbicides was confirmed, concerning the exposure period. In addition, the involvement of oxidative DNA damage on the action of Roundup(®) (pointed out as pyrimidine bases oxidation) was demonstrated, while for Garlon(®) this damaging mechanism was less evident. Fish exposed to Garlon(®), though presenting some evidence towards a tendency of recovery, did not achieve a complete restoration of DNA integrity. In what concerns to Roundup(®), a recovery was evident when considering non-specific DNA damage on day 14 post-exposure. In addition, this herbicide was able to induce a late oxidative DNA damage (day 14). Blood cells of A. anguilla exposed to

  4. The impact of wildfire on stream fishes in an Atlantic-Mediterranean climate: evidence from an 18-year chronosequence

    Directory of Open Access Journals (Sweden)

    Monaghan K.A.

    2016-01-01

    Full Text Available The predicted increase in wildfires associated with climate change poses a risk to freshwater biodiversity that may be exacerbated by river regulation. We studied the effects of wildfire and river management on the fish assemblages of Atlantic-Mediterranean streams in northern Portugal. Employing a chronosquence survey covering an 18-year gradient of impact-recovery from major fire events (ca. 100% catchment burnt, we assessed the ecological response with respect to time since wildfire, interpreting fish assemblages in the context of species traits and characteristics of the river habitat. Non-burnt sites (N = 18; surveyed 4 years previously were compared to burnt sites (N = 14, two of which were part of the non-burnt set, thus providing a Before-After Impact comparison (BAI; N = 2. Across burnt sites richness and abundance were not related to time since wildfire. BAI revealed a contrast in the response of different species that corresponded to descriptive evidence from the chronosequence of burnt sites. As resource specialists, Salmo trutta were negatively impacted by wildfire; Iberian endemic cyprinids, characterized by generalist traits, demonstrated resistance. Habitat structure was a key determinant of wildfire-impact, increasing with channel slope and the degree of channelization. The low abundance of migratory taxa (S. trutta and Anguilla anguilla at burnt sites suggested the importance of fish mobility to post-fire recovery. These data demonstrate that trait profiles and habitat descriptions provide pragmatic information for the management of rivers in fire-susceptible regions and suggest that the rehabilitation of these upland stream habitats might enhance ecological resistance and resilience to catchment wildfire.

  5. Does fish reproduction and metabolic activity influence metal levels in fish intestinal parasites, acanthocephalans, during fish spawning and post-spawning period?

    Science.gov (United States)

    Filipović Marijić, Vlatka; Vardić Smrzlić, Irena; Raspor, Biserka

    2014-10-01

    Application of fish intestinal parasites, acanthocephalans, as bioindicators in metal exposure assessment usually involves estimation of their metal levels and bioconcentration factors. Metal levels in parasite final host, fishes, are influenced by fish physiology but there is no data for acanthocephalan metal levels. Gastrointestinal Zn, Fe, Mn, Cd, Ag levels in European chub (Squalius cephalus L.) from the Sava River were significantly higher during chub spawning (April/May) compared to the post-spawning period (September). In acanthocephalans (Pomphorhynchus laevis and Acanthocephalus anguillae) significantly higher metal levels during chub spawning were observed only for Zn in P. laevis. Bioconcentration factors were twice as high for Fe, Mn, Ag, Pb in the post-spawning period, probably as a consequence of lower gastrointestinal metal levels in fish rather than metal exposure. Therefore, bioconcentration factors should be interpreted with caution, due to their possible variability in relation to fish physiology. In addition, gastrointestinal Cu, Cd and Pb levels were lower in infected than uninfected chub, indicating that metal variability in fishes might be affected by the presence of acanthocephalans.

  6. Drinking induced by angiotensin II in fishes.

    Science.gov (United States)

    Kobayashi, H; Uemura, H; Takei, Y; Itatsu, N; Ozawa, M; Ichinohe, K

    1983-02-01

    Among 20 species of freshwater fishes examined, Pseudorasbora parva, Rhodeus ocellatus, Cobitis anguillicaudatus, Carassius auratus, Oryzias latipes, Gambusia affinis, and Gyrinocheilus anymonieri were found to drink water like seawater fishes, while 13 remaining species did not drink. For fish species found exclusively in fresh water, angiotensin II (AII) treatment did not induce drinking. In contrast, those freshwater fishes which survive in estuarine brackish water (Leuciscus hakonensis, C. carassius, Parasilurus asotus, G. affinis, Chaenogobius annularis, Tridentiger obscurus, and G. anymonieri responded to AII by drinking. Furthermore, some freshwater fishes which survive either in hypertonic water (C. auratus) or in sea water (Anguilla japonica and O. latipes) also responded to AII by drinking. Of 17 seawater fishes examined, Eptatretus burgeri, Triakis scyllia, and Heterodontus japonicus failed to drink water, and for Trachurus japonicus, Platichthys bicoloratus, and Glossogobius giuris fasciatopunctatus, water intake was minor (similar to freshwater fishes). The 11 remaining seawater fishes drank water. AII did not induce drinking in fishes living exclusively in sea water. However, seawater fishes which survive either in tide pools (Chasmichthys dolichognathus gulosus) or in brackish water (Sillago japonica, Mugil cephalus, G. giuris fasciatopunctatus) responded to AII by drinking. P. bicoloratus, Acanthopagrus schlegeli, and Fugu niphobles were exceptional, in that they survive in brackish water, but did not respond to AII. Although some exceptions exist, it is generally concluded that a drinking response to AII is characteristic of fishes which encounter water more hypertonic than that in which they typically reside. Accordingly, a drinking mechanism induced by AII may be a compensatory emergency reaction to dehydration stress.

  7. Cadmium concentration in three species of freshwater fishes from Keuretoe River, Northern Aceh, Indonesia

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    Muhammad A. Sarong

    2013-09-01

    Full Text Available The objectives of present study was to evaluate cadmium (Cd concentration in some freshwater fishes found in Keuretoe Rivers and to determine the most effective freshwater fishes (Osphronemus goramy, Anguilla marmorata and Hemibagrus nemurus in accumulating of cadmium. A total of three sampling locations were determined using the purposive of random sampling. A total of three individual fishes at every sampling location were collected, the tissues were processed for Atomic Absorption Spectrophotometry (AAS and data were analyzed by Anova followed by Duncan multiple range test. The result revealed that the cadmium concentration ranges between 0.0064 ppm and 0.0260 ppm. Anova test showed that the sampling locations did not significantly affect the cadmium accumulation in fishes, but the fish species gave significantly effect on the cadmium accumulation in their tissue. The Duncan test showed that high cadmium accumulation was found in gourami at Station 2 and in mottled eel at Station 1, the concentrations were significantly different from Cd content in bagrid catfish at all sampling locations. The higher of cadmium pollution was recorded in Station 3 and gourami accumulated higher cadmium than other fishes studied. Keuretoe River is contaminated with cadmium and the fishes should not be consumed.

  8. The eel immune system: present knowledge and the need for research

    DEFF Research Database (Denmark)

    Nielsen, Michael Engelbrecht; Esteve-Gassent, M. D.

    2006-01-01

    The European eel, Anguilla anguilla, is one of the most important warm water fish species cultured in southern Europe and the Mediterranean as well as in northern countries including Germany, the Netherlands and Denmark. The Japanese eel, A. japonica, is an important cultured fish in several...

  9. The eel immune system: present knowledge and the need for research

    DEFF Research Database (Denmark)

    Nielsen, Michael Engelbrecht; Esteve-Gassent, M. D.

    2006-01-01

    The European eel, Anguilla anguilla, is one of the most important warm water fish species cultured in southern Europe and the Mediterranean as well as in northern countries including Germany, the Netherlands and Denmark. The Japanese eel, A. japonica, is an important cultured fish in several...... immune responses. This review summarizes the present knowledge relating to the eel immune system and includes new data....

  10. Nursery use of shallow habitats by epibenthic fishes in Maine nearshore waters

    Science.gov (United States)

    Lazzari, M. A.; Sherman, S.; Kanwit, J. K.

    2003-01-01

    Species richness and abundance of epibenthic fishes were quantified with daytime beam trawl tows in shallow water habitats during April-November 2000 of three mid-coast Maine estuaries: Casco Bay, Muscongus Bay and the Weskeag River. Five shallow (fishes were collected. Species richness per tow was greater in Casco Bay followed by the Weskeag River and Muscongus Bay. Catch per unit effort (CPUE) of fishes was greater in Casco Bay than in the Weskeag River or Muscongus Bay. Species richness and faunal abundances were positively associated with vegetation, particularly Zostera, at all sampling locations. CPUEs of fishes were higher in Zostera primarily due to the abundance of Gasterosteus aculeatus, Apeltes quadracus, Pungitius pungitius, Myoxocephalus aenaeus, and Cylcopterus lumpus. The fish community of mid-coast estuaries was dominated by young-of-the-year (YOY) and juvenile fishes and all of the habitat types function as nursery areas. Twelve species (38%) of commercial and recreational importance were collected in the three estuaries, but the percentage was higher in Casco Bay (44%) and the Weskeag River (46%). These species included Anguilla rostrata, Clupea harengus, Gadus morhua, Microgadus tomcod, Pollachius virens, Urophycis chuss, Urophycis regia, Urophycis tenuis, Osmerus mordax, Macrozoarces americanus, Tautogolabrus adspersus, and Pleuronectes americanus. Four species, G. morhua, M. tomcod, P. virens, and U. tenuis were more common in spring than summer or autumn. P. americanus was most abundant in summer followed by spring and autumn. This study documents the importance of shallow estuarine areas in Maine as nurseries for these species.

  11. ECONOMETRIC MODELLING OD THE INFLUENCE OF LAKE WATER QUALITY CHANGES ON FISHING ECONOMY

    Directory of Open Access Journals (Sweden)

    Marek Antoni Ramczyk

    2017-06-01

    Full Text Available The econometric model can be a precise instrument for the analysis of the impact of the natural environment's degradation on fishing economy. This paper aims at analysing the influence of the water quality changes in lake Charzykowskie on the fishing economy. This dissertation present the results of a research on the lake water pollution's impact on fishing economy. The economic-ecological models have been constructed, explaining the changes of economic effects of the lake fishery in the conditions of an increasing water pollution in the epilimnion on the example of the catch of Rutilus rutilus, Abramis brama, Blicca bjoerkna, Coregonus albula, Coregonus lavaretus, Anguilla anguilla and Esox lucius in Lake Charzykowskie. Performed empirical research looked into the influence of the environmental factors on the size of fish catch. Calculations and analysis show clearly that though the habitat factors do influence the catch size of each studied fish species, they do it with different intensity and in various combinations. Both lake water quality and climate factors changes cause measurable effects on fishing industry of lake Charzykowskie. Among all the examined Rutilus rutilus, Abramis brama and Blicca bjoerkna the highest environmental requirements concerning water quality has Blicca bjoerkna. Whereas Abramis brama has slightly higher environmental requirements than Rutilus rutilus. Empirical calculations showed as well that Coregonus albula and Coregonus lavaretus have considerably higher water cleanness requirements than Rutilus rutilus, Abramis brama and Blicca bjoerkna. While when talking about Rutilus rutilus, Abramis brama and Blicca bjoerkna, most water characteristics still rather stimulated these species' development, when it comes to Coregonus albula and Coregonus lavaretus, in general they suppressed their development. The model has also proved quite high habitat requierements of Anquilla anquilla and correctness of the thesis that

  12. Summer use of the tidal freshwaters of the River Seine by three estuarine fish: Coupling telemetry and GIS spatial analysis

    Science.gov (United States)

    Le Pichon, C.; Coustillas, J.; Zahm, A.; Bunel, M.; Gazeau-Nadin, C.; Rochard, E.

    2017-09-01

    Acoustic telemetry and GIS-based spatial analysis were used to investigate the summer habitat use and movement patterns of three fish species in the tidal freshwaters of the Seine estuary (France). Experimental displacement of tagged individuals of thin-lipped grey mullet (Liza ramada), European eel (Anguilla anguilla), and common bream (Abramis brama) were conducted to test for their spatial fidelity and home range establishment. Most tagged individuals (95%) successfully returned to their previously occupied capture site, showing spatial homing abilities. The studied upstream tidal freshwater segment of the Seine estuary was regularly used by grey mullet as a part of its larger summer home range, while European eel and common bream were resident in this segment. The fidelity of eel to small nocturnal refuges and the regular use of intertidal waterbodies at high tide by grey mullet and bream suggested that they possess a capacity of acquiring spatial memory of habitats in a fluctuating environment. Importantly, the scale of movements travelled by each species was positively related to tidal phase. Grey mullet and bream, both visual feeders, exhibited short-term tidal movements to known habitats, providing food resources and contiguous resting habitat suggesting that they have shown behavioural strategies adaptive to fluctuating environments. Eel, in contrast, was found to have a different strategy strongly related to diel dynamics: it stayed in subtidal habitats rich in refuges that remained available at low tide. The results of this study emphasize the importance of restoring intertidal waterbodies and the relevance of considering the availability of adjacent subtidal habitats providing refuge at low tides.

  13. Progress On Intestinal Oligopeptide Transporter PepT1 of Fishes%鱼类肠道小肽转运载体PepT1的研究进展

    Institute of Scientific and Technical Information of China (English)

    叶万里; 李英文

    2009-01-01

    从生理特性,cDNA序列和蛋白质分子结构,组织分布与表达这三个方面叙述了欧洲鳗鲡(Anguilla anguilla),罗非鱼(Oreochromis mossambicus),rockfish(Sebastes caurinus),银鱼(Chionodraco hamatus),斑马鱼(Danio rerio),亚洲泥鳅(Misgurnus anguillicaudatus),大西洋鳕鱼(Gadus morhua)和欧洲黑鲈(Dicentrarchus labrax)中有关肠道Ⅰ型肽转运载体(PepT1)方面的研究进展情况.

  14. Slow muscle power output of yellow- and silver-phase European eels (Anguilla anguilla L.) : changes in muscle performance prior to migration

    NARCIS (Netherlands)

    Ellerby, D.J.; Spierts, I.L.Y.; Altringham, J.D.

    2001-01-01

    Eels swim in the anguilliform mode in which the majority of the body axis undulates to generate thrust. For this reason, muscle function has been hypothesised to be relatively uniform along the body axis relative to some other teleosts in which the caudal fin is the main site of thrust production. T

  15. Influence of Temperature, Environmental Salinity and Fasting on the Patterns of Fatty Acid Synthesized by Gills and Liver of the European Eel (Anguilla Anguilla)

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Abraham, S.

    1983-01-01

    A rise in temperature on the average from 8 to 28 degrees C resulted in an enhanced relative incorporation of 1-14Cacetate into saturated fatty acids in liver tissue. The same effect was seen in gill tissue, but only after incubation in vitro and when the precursor was injected into the eel. When...... there was a significantly enhanced percentage incorporation into saturated gill fatty acids in fresh water relative to sea water. Fasting led to less relative incorporation of 1-14Cacetate into saturated liver fatty acids in vitro.......-14Cacetate was added to the water in the incubation tank such a "homeoviscous adaption" was not observed in gill tissue. A rise in temperature resulted in less relative incorporation of radioactivity into saturated gill fatty acids. We attribute this difference to a specific labelling of salt transport cells...... in the gills, due to the labelled precursor itself taking part in biological ion transport when it is added to the water. It would appear that palmitoleic acid plays a special role in the function of the salt transport cell. When 1-14Cacetate was added to the water in the incubation tank...

  16. Effects of feed composition on life history developments in feed intake, metabolism, growth and body composition of European eel, Anguilla anguilla

    NARCIS (Netherlands)

    Heinsbroek, L.T.N.; Hooff, P.L.A.; Swinkels, W.; Tanck, M.W.T.; Schrama, J.W.; Verreth, J.A.J.

    2007-01-01

    To examine the effect of feed composition on changes in feed intake and subsequent feed utilization with age, five populations of European eel, with an average initial body weight of 5 g each fed a different diet, were monitored for 302 d. The five feeds differed in their content of crude protein

  17. ÉTUDE EXPÉRIMENTALE DES COMPORTEMENTS DE CIVELLES D’ANGUILLA ANGUILLA L. INFLUENCE DE LA DENSITÉ ET DE LA DISPONIBILITÉ EN ABRIS

    Directory of Open Access Journals (Sweden)

    BARDONNET A.

    2005-10-01

    Full Text Available Les comportements d’émigration et d’utilisation de l’espace développés par des civelles ont été observés dans des bacs et plans d’eau expérimentaux. Dans les bacs accueillant 55 ind./m2 sans possibilité d’émigration, la densité d’abris végétaux a été contrôlée (densités d’abris basse, 2 tiges de végétation artificielle par bac ou haute, 9 tiges par bac et le suivi a duré 2 mois et demi. Dans les plans d’eau ouverts, la densité de civelles introduites a été définie selon plusieurs modalités (1,6 - 6 - 9 et 12 ind./m2 et le suivi a duré 1 mois et demi. En bacs, après une période de 5 à 6 jours, les abris sont fortement recherchés pendant environ 6 semaines, les individus montrant alors une forte grégarité. Cette dernière disparaît ensuite, les abris sont alors moins recherchés et des comportements agressifs font leur apparition. En plans d’eau, les sorties concernent en moyenne 17 % du stock initial (mini = 7 %, maxi = 35 %, interviennent rapidement et sont presque toutes dirigées vers l’amont. Leur intensité ne dépend pas de la densité initiale et apparaît plus importante dans les bassins sans herbier. Les tailles et poids moyens des émigrants sont plus importants que ceux du lot initial. Au terme du suivi, la croissance apparaît forte, hétérogène et associée à une faible survie dans les plans d’eau peu ou moyennement alevinés. Elle apparaît plus faible, homogène et associée à une bonne survie dans les bassins à forte densité initiale. Ces observations sont compatibles avec l’expression d’un comportement grégaire en condition de densité importante, comportement favorisant une croissance homogène, ayant pour conséquence de retarder l’apparition d’actes agressifs. Au contraire, dans des contextes de faible densité, l’expression rapide du potentiel de croissance de quelques individus favoriserait l’apparition d’actes agressifs.

  18. Macroparasite communities in European eels, Anguilla anguilla, from French Mediterranean lagoons, with special reference to the invasive species Anguillicola crassus and Pseudodactylogyrus spp.

    Directory of Open Access Journals (Sweden)

    G. Fazio

    2008-01-01

    Full Text Available European eel parasites, in particular invasive species, are suspected to play a role in the decline in the populations of their host. The aims of this work were to describe the parasitic fauna of eels in French Mediterranean lagoons and to study the epidemiological trends of the invasive helminth species, the nematode Anguillicola crassus and the monogenean Pseudodactylogyrus spp., in regard to spatio-temporal dynamics, host biological characteristics and parasite community. A total of 418 eels was sampled in eight lagoons between March 2003 and June 2005. Our results revealed a total macroparasite richness of 23 species: 1 Monogenea, 13 Digenea, 2 Cestoda, 3 Nematoda, 2 Acantocephala and 2 Crustacea. We found no variation in A. crassus abundance in Salses-Leucate lagoon in the same month across years. However, the nematode abundance was higher in eels caught in summer than in those caught in winter. Pseudodactylogyrus sp. was not found in Salses-Leucate lagoon, except in July 2004. Comparisons between the lagoons on the same date showed that they could be separated into two groups for both species' abundance: Grau-du-Roi, Mauguio, Palavas and Vaccarès lagoons, where abundance was rather high, against Bages-Sigean, Pierre-Blanche, Salses-Leucate and Thau lagoons, where abundance was rather low or nil. We found significant negative relationships between A. crassus abundance and the length and age of eels. We also found a significant positive relationship between A. crassus and Pseudodactylogyrus sp. abundance. Finally, our results showed significant positive relationships between both A. crassus and Pseudodactylogyrus sp. abundance and the abundance of the digeneans Prosorhynchus aculeatus and Lecithochirium gravidum. We discuss the results in regard to the dynamics of invasions, the characteristics of the parasite life cycles and the ecology of eels.

  19. The Effect of Prolonged Fasting on Total Lipid Synthesis and Enzyme Activities in the Liver of the European Eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Abraham, S. A.; Hansen, Heinz Johs. Max; Hansen, F.N.

    1984-01-01

    The extent of fatty acid synthesis from [1-14C]acetate in liver slices was reduced 6-fold when eels were fasted for 1-7 wk and 20-fold when fasted for 39 wk, thereafter hepatic lipogenesis seemed to remain constant for up to 95 wk of fasting. After a 1-3 wk fast some hepatic enzyme activities were...... total lipid synthesis and lipogenic enzyme activity in eel liver was 30.degree. C....... reduced (acetyl-CoA carboxylase decreased 2-fold and fatty acid synthetase declined 5-fold); others remained unchanged (G-6-P dehydrogenase, 6-phosphogluconate dehydrogenase, .alpha.-glycerol phosphate dehydrogenase as well as malic enzyme and ATP-citrate lyase). The optimum temperature for measuring both...

  20. Slow muscle power output of yellow- and silver-phase European eels (Anguilla anguilla L.) : changes in muscle performance prior to migration

    NARCIS (Netherlands)

    Ellerby, D.J.; Spierts, I.L.Y.; Altringham, J.D.

    2001-01-01

    Eels swim in the anguilliform mode in which the majority of the body axis undulates to generate thrust. For this reason, muscle function has been hypothesised to be relatively uniform along the body axis relative to some other teleosts in which the caudal fin is the main site of thrust production. T

  1. L'anguille européenne Anguilla anguilla, un poisson sensible aux stress environnementaux et vulnérable à diverses atteintes pathogènes

    Directory of Open Access Journals (Sweden)

    BRUSLÉ J.

    1994-10-01

    L'ensemble des connaissances démontre largement que ce poisson n'est pas aussi résistant qu'il est généralement admis. Sa sensibilité, sa vulnérabilité vis-à-vis d'un ensemble de facteurs défavorables (dégradation de la qualité des habitats, altérations de la qualité de l'eau, parasitoses et bactérioses ... contribuent à une très importante réduction du stock européen et justifient pleinement son récent statut d'espèce menacée.

  2. Reliability of non-lethal assessment methods of body composition and energetic status exemplified by applications to eel (Anguilla anguilla) and carp (Cyprinus carpio)

    DEFF Research Database (Denmark)

    Klefoth, Thomas; Skov, Christian; Aarestrup, Kim;

    2013-01-01

    ),bioelectric impedance-based assessments of body composition (BIA), and microwave-based “fat” meters(FM). Previous studies have revealed mixed findings as to the reliability of each of these. We compared theperformance of Kn, BIA and FM at different temperatures to predict energetic status of the whole bodiesof live eel...

  3. Données sur la croissance de l'anguille (Anguilla anguilla L. dans le cours moyen du Rhin, région alsacienne

    Directory of Open Access Journals (Sweden)

    MEUNIER F. J.

    1994-10-01

    Full Text Available La capture régulière, pendant cinq années (1990-94, d'anguilles marquées à la tétracycline au stade civelle et déversées dans le Rhin en mars 1989, confirme la forte variabilité individuelle de leur croissance. La croissance moyenne annuelle, sexes confondus, est de 55 mm, avec un accroissement voisin de 100 mm lors de la première année de vie en eau douce. Ces valeurs se situent dans les limites des résultats obtenus pour d'autres rivières, lacs ou lagunes de l'Europe occidentale.

  4. Effects of feed composition on life history developments in feed intake, metabolism, growth and body composition of European eel, Anguilla anguilla

    NARCIS (Netherlands)

    Heinsbroek, L.T.N.; Hooff, P.L.A.; Swinkels, W.; Tanck, M.W.T.; Schrama, J.W.; Verreth, J.A.J.

    2007-01-01

    To examine the effect of feed composition on changes in feed intake and subsequent feed utilization with age, five populations of European eel, with an average initial body weight of 5 g each fed a different diet, were monitored for 302 d. The five feeds differed in their content of crude protein (3

  5. Macroparasite communities in European eels, Anguilla anguilla, from French Mediterranean lagoons, with special reference to the invasive species Anguillicola crassus and Pseudodactylogyrus spp.

    Directory of Open Access Journals (Sweden)

    Fazio G.

    2009-04-01

    Full Text Available European eel parasites, in particular invasive species, are suspected to play a role in the decline in the populations of their host. The aims of this work were to describe the parasitic fauna of eels in French Mediterranean lagoons and to study the epidemiological trends of the invasive helminth species, the nematode Anguillicola crassus and the monogenean Pseudodactylogyrus spp., in regard to spatio-temporal dynamics, host biological characteristics and parasite community. A total of 418 eels was sampled in eight lagoons between March 2003 and June 2005. Our results revealed a total macroparasite richness of 23 species: 1 Monogenea, 13 Digenea, 2 Cestoda, 3 Nematoda, 2 Acantocephala and 2 Crustacea. We found no variation in A. crassus abundance in Salses-Leucate lagoon in the same month across years. However, the nematode abundance was higher in eels caught in summer than in those caught in winter. Pseudodactylogyrus sp. was not found in Salses-Leucate lagoon, except in July 2004. Comparisons between the lagoons on the same date showed that they could be separated into two groups for both species' abundance: Grau-du-Roi, Mauguio, Palavas and Vaccarès lagoons, where abundance was rather high, against Bages-Sigean, Pierre-Blanche, Salses-Leucate and Thau lagoons, where abundance was rather low or nil. We found significant negative relationships between A. crassus abundance and the length and age of eels. We also found a significant positive relationship between A. crassus and Pseudodactylogyrus sp. abundance. Finally, our results showed significant positive relationships between both A. crassus and Pseudodactylogyrus sp. abundance and the abundance of the digeneans Prosorhynchus aculeatus and Lecithochirium gravidum. We discuss the results in regard to the dynamics of invasions, the characteristics of the parasite life cycles and the ecology of eels.

  6. Eimeria that infect fish are diverse and are related to, but distinct from, those that infect terrestrial vertebrates.

    Science.gov (United States)

    Molnár, Kálmán; Ostoros, Györgyi; Dunams-Morel, Detiger; Rosenthal, Benjamin M

    2012-12-01

    The Eimeria are ubiquitous parasites (Phylum: Apicomplexa; family: Coccidia) of the gut epithelium of vertebrates which complete their development in a single host species and whose sporocysts may be recognized by the presence of a Stieda body through which their sporozoites excyst. Their diversity and relationship to other kinds of coccidia have been successfully explored by molecular systematic studies based on the sequencing the 18S ribosomal DNA. To date, most attention has been paid to the diversity and evolutionary relationships of Eimeria spp. parasitizing terrestrial vertebrates, most especially those species infecting domesticated birds and mammals. Regrettably, no Eimeria have yet been considered from the Earth's first vertebrates: the fish. If Eimeria first evolved in fish, then extant piscine parasites should comprise a deeply branching assemblage at the base of well-constructed phylogenetic trees. Here, we sequenced portions of ribosomal DNA from several such isolates (from Eimeria anguillae, Eimeria daviesae, Eimeria percae, Eimeria variabilis, Eimeria rutili and Eimeria nemethi) and compared them to one another as well as to other available sequences from the parasites of fish and terrestrial vertebrates, in order to better understand their diversity and origins. By establishing that such piscine parasites comprise a deeply branching clade at the base of the Eimeriidae, these data substantiate the hypothesis that Eimeria may have originated in fish. Plainly, a great deal of coccidian diversity awaits future discovery and description.

  7. Different ossification patterns of intermuscular bones in fish with different swimming modes.

    Science.gov (United States)

    Yao, Wenjie; Lv, Yaoping; Gong, Xiaoling; Wu, Jiaming; Bao, Baolong

    2015-01-01

    Intermuscular bones are found in the myosepta in teleosts. However, there is very little information on the development and ossification of these intermuscular bones. In this study, we performed an in-depth investigation of the ossification process during development in zebrafish (Danio rerio) and Japanese eel (Anguilla japonica). In Japanese eel, a typical anguilliform swimmer, the intermuscular bones ossified predominantly from the anterior to the posterior. By contrast, in the zebrafish, a sub-carangiform or carangiform swimmer, the intermuscular bones ossified predominantly from the posterior to the anterior regions of the fish. Furthermore, tail amputation affected the ossification of the intermuscular bones. The length of the intermuscular bones in the posterior area became significantly shorter in tail-amputated zebrafish and Japanese eels, and both had less active and lower swimming speeds; this indicates that swimming might induce the ossification of the intermuscular bones. Moreover, when a greater length of tail was amputated in the zebrafish, the intermuscular bones became even shorter. Tail amputation affected the length and ossification of intermuscular bones in the anterior part of the fish, close to the head, differently between the two fish: they became significantly shorter in the zebrafish, but did not in the Japanese eel. This might be because tail amputation did not significantly affect the undulations in the anterior of the Japanese eel, especially near the head. This study shows that the ossification of intermuscular bones might be induced through mechanical force loadings that are produced by swimming.

  8. Different ossification patterns of intermuscular bones in fish with different swimming modes

    Directory of Open Access Journals (Sweden)

    Wenjie Yao

    2015-12-01

    Full Text Available Intermuscular bones are found in the myosepta in teleosts. However, there is very little information on the development and ossification of these intermuscular bones. In this study, we performed an in-depth investigation of the ossification process during development in zebrafish (Danio rerio and Japanese eel (Anguilla japonica. In Japanese eel, a typical anguilliform swimmer, the intermuscular bones ossified predominantly from the anterior to the posterior. By contrast, in the zebrafish, a sub-carangiform or carangiform swimmer, the intermuscular bones ossified predominantly from the posterior to the anterior regions of the fish. Furthermore, tail amputation affected the ossification of the intermuscular bones. The length of the intermuscular bones in the posterior area became significantly shorter in tail-amputated zebrafish and Japanese eels, and both had less active and lower swimming speeds; this indicates that swimming might induce the ossification of the intermuscular bones. Moreover, when a greater length of tail was amputated in the zebrafish, the intermuscular bones became even shorter. Tail amputation affected the length and ossification of intermuscular bones in the anterior part of the fish, close to the head, differently between the two fish: they became significantly shorter in the zebrafish, but did not in the Japanese eel. This might be because tail amputation did not significantly affect the undulations in the anterior of the Japanese eel, especially near the head. This study shows that the ossification of intermuscular bones might be induced through mechanical force loadings that are produced by swimming.

  9. The meningeal sheath of the regenerating spinal cord of the eel, Anguilla.

    Science.gov (United States)

    Dervan, Adrian G; Roberts, Barry L

    2003-09-01

    We describe here the meningeal sheath that encloses the spinal cord, and the sheath that develops when the cord regenerates after a total transection. This description is derived from electron and light microscopy. The sheath of the uninjured cord was found to be a single structure of two parts: an outer, thin melanocyte layer and an inner, thicker layer of 2 to 10 rows of fibroblasts, closely associated with collagen and elastic fibers. Soon after cord transection, the injured axons re-grow and, together with the reforming central canal, create a bridge that links the transected cord within 8 days of injury. This bridge is covered at first by a rudimentary meningeal sheath, formed of fibroblasts and macrophages, that later progressively thickens and becomes more compact. By about day 20, the fibroblasts are arranged as 16 to 20 loose rows that include bundles of collagen, oriented along the rostro-caudal axis of the cord. Even after 144 days, the meninx, although substantially thicker than normal because of the numerous fibroblast rows (20 to 30), still lacks the melanocyte layer. In cases in which the meninx at the transection site was mechanically and pharmacologically (6-hydroxydopamine) disrupted, bridge formation was essentially unchanged, and axonal regrowth continued; some regrowing axons, however, extruded from the denuded cord. Accordingly, our findings indicate that although the meningeal sheath is not essential for cord regeneration to take place, it may well facilitate recovery by providing mechanical guidance and support to the regrowing axons.

  10. Low PCB concentrations observed in American eel (Anguilla rostrata) in six Hudson River tributaries

    Science.gov (United States)

    Limburg, K.E.; Machut, L.S.; Jeffers, P.; Schmidt, R.E.

    2008-01-01

    We analyzed 73 eels, collected in 2004 and 2005 above the head of tide in six Hudson River tributaries, for total PCBs, length, weight, age, and nitrogen stable isotope ratios (??15N). Mean total PCB concentration (wet weight basis) was 0.23 ppm ?? 0.08 (standard error), with a range of 0.008 to 5.4 ppm. A majority of eels (84) had concentrations below 0.25 ppm, and only seven eels (10%) had concentrations exceeding 0.5 ppm. Those eels with higher PCB concentrations were ???12 yr; there was a weak correlation of PCB concentration with ??15N and also with weight. Compared to recent (2003) data from the mainstem of the Hudson River estuary, these results indicate that tributaries are generally much less contaminated with PCBs. We hypothesize that those tributary eels with high PCB concentrations were relatively recent immigrants from the mainstem. Given concern over the possible adverse effects of PCBs on eel reproduction, these tributaries may serve as refugia. Therefore, providing improved access to upland tributaries may be critically important to this species. ?? 2008 Northeastern Naturalist.

  11. The effect of para-nonylphenol on Japanese eel (Anguilla japonica) spermatogenesis in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Miura, C. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); ' Times Arrow and Biosignaling' PRESTO Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan); Takahashi, N. [Iwate Fisheries Technology Center, Fisheries and Resource Management Division, 3-75-3 Oaza-hirata, Kamaishi, Iwate 026-0001 (Japan); Michino, F. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Miura, T. [Laboratory of Fish Reproductive Physiology, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790-8566 (Japan); ' Times Arrow and Biosignaling' PRESTO Japan Science and Technology Agency, Kawaguchi 332-0012 (Japan)

    2005-01-26

    Endocrine disrupters have been recognized to interfere with endocrine systems that regulate reproduction, for example, by mimicking or inhibiting the action of endogenous sex steroid hormones including estradiol-17{beta} (E2). In the present study, we examined the effect of an endocrine disrupter, para-nonylphenol (p-NP) on spermatogenesis, and compared it with the action of E2, using an eel testicular organ culture system. p-NP alone stimulated early spermatogonial renewal in the same manner as E2. Neither induced further progress in spermatogenesis. In the presence of 11-ketotestosterone (11-KT), the major androgen in teleosts, p-NP did not prevent the 11-KT-induced progress in spermatogenesis. However, this treatment enlarged the Sertoli cells. Electron microscopic observation revealed that enlarged Sertoli cells contained well-developed organelles. Moreover, the proportion of germ cells appeared to have decreased as a result of Sertoli cell hypertrophy. These results clearly show that p-NP has an effect on Sertoli cells in the presence of an androgen (11-KT), potentially disturbing 11-KT-induced spermatogenesis.

  12. Umur glas eel (Anguilla spp. yang masuk muara Sungai Progo Yogyakarta

    Directory of Open Access Journals (Sweden)

    Agung Budiharjo

    2017-03-01

    Full Text Available The leptocephalus drift with sea currents and moving from spawning area into coastal area near mouth of Progo River. In thecoastal area, leptocephalus metamorfosed into glass eel, after that glass eel migrated to river. The aims of this research were to estimate glass eels age and predict hatching dates. Glass eels sampled on new moon during Februari 2007-Mei 2009 at mouth of Progo River.Glass eel ages estimated using their otolith micro structure. Hatching dates predicted with back calculation of glass eels age. We collected 1.082 glass eels. The ages of glass eel at recruit ranged from 58 to 190 days, and divided into 5 age groups. Glass eels are migrated to river hatched on a "new moon" from July to January. Glass eels are migrated to river during October-January hatched during July-October. Glass eels are migrated to river during February-Juny hatched during November-January.

  13. Linking landscapes and habitat suitability scores for diadromous fish restoration in the susquehanna river basin

    Science.gov (United States)

    Kocovsky, P.M.; Ross, R.M.; Dropkin, D.S.; Campbell, J.M.

    2008-01-01

    Dams within the Susquehanna River drainage, Pennsylvania, are potential barriers to migration of diadromous fishes, and many are under consideration for removal to facilitate fish passage. To provide useful input for prioritizing dam removal, we examined relations between landscape-scale factors and habitat suitability indices (HSIs) for native diadromous species of the Susquehanna River. We used two different methods (U.S. Fish and Wildlife Service method: Stier and Crance [1985], Ross et al. [1993a, 1993b, 1997], and Pardue [1983]; Pennsylvania State University method: Carline et al. [1994]) to calculate HSIs for several life stages of American shad Alosa sapidissima, alewives Alosa pseudoharengus, and blueback herring Alosa aestivalis and a single HSI for American eels Anguilla rostrata based on habitat variables measured at transects spaced every 5 km on six major Susquehanna River tributaries. Using geographical information systems, we calculated land use and geologic variables upstream from each transect and associated those data with HSIs calculated at each transect. We then performed canonical correlation analysis to determine how HSIs were linked to geologic and land use factors. Canonical correlation analysis identified the proportion of watershed underlain by carbonate rock as a positive correlate of HSIs for all species and life stages except American eels and juvenile blueback herring. We hypothesize that potential mechanisms linking carbonate rock to habitat suitability include increased productivity and buffering capacity. No other consistent patterns of positive or negative correlation between landscape-scale factors and HSIs were evident. This analysis will be useful for prioritizing removal of dams in the Susquehanna River drainage, because it provides a broad perspective on relationships between habitat suitability for diadromous fishes and easily measured landscape factors. This approach can be applied elsewhere to elucidate relationships

  14. Cooling water of power plant creates "hot spots" for tropical fishes and parasites.

    Science.gov (United States)

    Emde, Sebastian; Kochmann, Judith; Kuhn, Thomas; Dörge, Dorian D; Plath, Martin; Miesen, Friedrich W; Klimpel, Sven

    2016-01-01

    Thermally altered water bodies can function as "hot spots" where non-native species are establishing self-sustaining populations beyond their tropical and subtropical native regions. Whereas many tropical fish species have been found in these habitats, the introduction of non-native parasites often remains undetected. Here, n = 77 convict cichlids (Amatitlania nigrofasciata) were sampled by electro-fishing at two sites from a thermally altered stream in Germany and examined for parasite fauna and feeding ecology. Stomach content analysis suggests an opportunistic feeding strategy of A. nigrofasciata: while plant material dominated the diet at the warm water inlet (∼30 °C), relative contributions of insects, plants, and crustaceans were balanced 3 km downstream (∼27 °C). The most abundant non-native parasite species was the tropical nematode Camallanus cotti with P = 11.90 % and P = 80.00 % at the inlet and further downstream, respectively. Additionally, nematode larvae of Anguillicoloides crassus and one specimen of the subtropical species Bothriocephalus acheilognathi were isolated. A. nigrofasciata was also highly infected with the native parasite Acanthocephalus anguillae, which could be linked to high numbers of the parasite's intermediate host Asellus aquaticus. The aim of this study was to highlight the risk and consequences of the release and establishment of ornamental fish species for the introduction and spread of non-indigenous metazoan parasites using the convict cichlid as a model species. Furthermore, the spread of non-native parasites into adjacent fish communities needs to be addressed in the future as first evidence of Camallanus cotti in native fish species was also found.

  15. Contrasting fish assemblages in free-flowing and impounded tributaries to the Upper Delaware River: Implications for conserving biodiversity

    Science.gov (United States)

    Baldigo, Barry P.; Delucia, Mari-Beth; Keller, Walter D.; Schuler, George E.; Apse, Colin D.; Moberg, Tara

    2015-01-01

    The Neversink River and the Beaver Kill in southeastern New York are major tributaries to the Delaware River, the longest undammed river east of the Mississippi. While the Beaver Kill is free flowing for its entire length, the Neversink River is subdivided by the Neversink Reservoir, which likely affects the diversity of local fish assemblages and health of aquatic ecosystems. The reservoir is an important part of the New York City waster-supply system that provides drinking water to more than 9 million people. Fish population and community data from recent quantitative surveys at comparable sites in both basins were assessed to characterize the differences between free-flowing and impounded rivers and the extent of reservoir effects to improve our capacity to define ecosystems responses that two modified flow-release programs (implemented in 2007 and 2011) should produce in the Neversink River. In general, the continuum of changes in fish assemblages which normally occur between headwaters and mouth was relatively uninterrupted in the Beaver Kill, but disrupted by the mid-basin impoundment in the Neversink River. Fish assemblages were also adversely affected at several acidified sites in the upper Neversink River, but not at most sites assessed herein. The reservoir clearly excluded diadromous species from the upper sub-basin, but it also substantially reduced community richness, diversity, and biomass at several mid-basin sites immediately downstream from the impoundment. There results will aid future attempts to determine if fish assemblages respond to more natural, yet highly regulated, flow regimes in the Neversink River. More important, knowledge gained from this study can help optimize use of valuable water resources while promoting species of special concern, such as American eel (Anguilla rostrata) and conserving biodiversity in Catskill Mountain streams.

  16. Broodstock management and hormonal manipulations of fish reproduction.

    Science.gov (United States)

    Mylonas, Constantinos C; Fostier, Alexis; Zanuy, Silvia

    2010-02-01

    Control of reproductive function in captivity is essential for the sustainability of commercial aquaculture production, and in many fishes it can be achieved by manipulating photoperiod, water temperature or spawning substrate. The fish reproductive cycle is separated in the growth (gametogenesis) and maturation phase (oocyte maturation and spermiation), both controlled by the reproductive hormones of the brain, pituitary and gonad. Although the growth phase of reproductive development is concluded in captivity in most fishes-the major exemption being the freshwater eel (Anguilla spp.), oocyte maturation (OM) and ovulation in females, and spermiation in males may require exogenous hormonal therapies. In some fishes, these hormonal manipulations are used only as a management tool to enhance the efficiency of egg production and facilitate hatchery operations, but in others exogenous hormones are the only way to produce fertilized eggs reliably. Hormonal manipulations of reproductive function in cultured fishes have focused on the use of either exogenous luteinizing hormone (LH) preparations that act directly at the level of the gonad, or synthetic agonists of gonadotropin-releasing hormone (GnRHa) that act at the level of the pituitary to induce release of the endogenous LH stores, which, in turn act at the level of the gonad to induce steroidogenesis and the process of OM and spermiation. After hormonal induction of maturation, broodstock should spawn spontaneously in their rearing enclosures, however, the natural breeding behavior followed by spontaneous spawning may be lost in aquaculture conditions. Therefore, for many species it is also necessary to employ artificial gamete collection and fertilization. Finally, a common question in regards to hormonal therapies is their effect on gamete quality, compared to naturally maturing or spawning broodfish. The main factors that may have significant consequences on gamete quality-mainly on eggs-and should be considered

  17. Contribution de l'otolithométrie à l'étude de la dynamique de la migration larvaire de l'anguille européenne (Anguilla anguilla

    Directory of Open Access Journals (Sweden)

    LECOMTE-FINIGER R.

    1994-10-01

    Une étude microstructurale des sagittae de civelles transparentes a permis, non seulement de décrire les étapes antérieures de la vie larvaire marine, mais aussi, d'estimer l'âge absolu des civelles par comptabilisation de l'ensemble des accroissements journaliers. Une telle connaissance permet de déduire la période de ponte des anguilles argentées en Mer des Sargasses.

  18. Influence de la luminosité nocturne et de la turbidité sur le comportement vertical de migration de la civelle d'anguille (Anguilla anguilla L. dans l'estuaire de l'Adour

    Directory of Open Access Journals (Sweden)

    DE CASAMAJOR M. N.

    1999-07-01

    Compte tenu des observations effectuées, le schéma migratoire vertical de l'espèce peut être modélisé de la manière suivante : l'interaction entre la luminosité nocturne et la turbidité influence les déplacements de civelles dans la colonne d'eau en relation avec leur comportement lucifuge. Plus la lumière nocturne qui pénètre dans la colonne d'eau est importante et plus les civelles migrent en profondeur.

  19. A nose-to-nose comparison of the physiological effects of exposure to ionic silver versus silver chloride in the European eel (Anguilla anguilla) and the rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Grosell, M.; Hogstrand, C.; Wood, C.M.;

    2000-01-01

    of Na+ leading to net Na+ loss were the key toxic effect in both species. In the rainbow trout, but not in the European eel, Cl- influx was also impaired during silver exposure. However, even under control conditions, Cl- influx was negligible in the eel. Water Cl- clearly protected against the silver......-induced physiological disturbance in rainbow trout, presumably by changing the speciation of silver from ionic silver to AgCl complexes. However, such a protective effect-was not observed in the European eel. Differences in whole body Na+ turnover rates between the two species (1.1% per day in the European eel versus...

  20. Evaluation of multi-scale climate effects on annual recruitment levels of the Japanese eel, Anguilla japonica, to Taiwan.

    Science.gov (United States)

    Tzeng, Wann-Nian; Tseng, Yu-Heng; Han, Yu-San; Hsu, Chih-Chieh; Chang, Chih-Wei; Di Lorenzo, Emanuele; Hsieh, Chih-Hao

    2012-01-01

    Long-term (1967-2008) glass eel catches were used to investigate climatic effects on the annual recruitment of Japanese eel to Taiwan. Specifically, three prevailing hypotheses that potentially explain the annual recruitment were evaluated. Hypothesis 1: high precipitation shifts the salinity front northward, resulting in favorable spawning locations. Hypothesis 2: a southward shift of the position of the North Equatorial Current (NEC) bifurcation provides a favorable larval transport route. Hypothesis 3: ocean conditions (eddy activities and productivity) along the larval migration route influence larval survival. Results of time series regression and wavelet analyses suggest that Hypothesis 1 is not supported, as the glass eel catches exhibited a negative relationship with precipitation. Hypothesis 2 is plausible. However, the catches are correlated with the NEC bifurcation with a one-year lag. Considering the time needed for larval transport (only four to six months), the one-year lag correlation does not support the direct transport hypothesis. Hypothesis 3 is supported indirectly by the results. Significant correlations were found between catches and climate indices that affect ocean productivity and eddy activities, such as the Quasi Biennial Oscillation (QBO), North Pacific Gyre Oscillation (NPGO), Pacific Decadal Oscillation (PDO), and Western Pacific Oscillation (WPO). Wavelet analysis reveals three periodicities of eel catches: 2.7, 5.4, and 10.3 years. The interannual coherence with QBO and the Niño 3.4 region suggests that the shorter-term climate variability is modulated zonally by equatorial dynamics. The low-frequency coherence with WPO, PDO, and NPGO demonstrates the decadal modulation of meridional teleconnection via ocean-atmosphere interactions. Furthermore, WPO and QBO are linked to solar activities. These results imply that the Japanese eel recruitment may be influenced by multi-timescale climate variability. Our findings call for investigation of extra-tropical ocean dynamics that affect survival of eels during transport, in addition to the existing efforts to study the equatorial system.

  1. Evaluation of multi-scale climate effects on annual recruitment levels of the Japanese eel, Anguilla japonica, to Taiwan.

    Directory of Open Access Journals (Sweden)

    Wann-Nian Tzeng

    Full Text Available Long-term (1967-2008 glass eel catches were used to investigate climatic effects on the annual recruitment of Japanese eel to Taiwan. Specifically, three prevailing hypotheses that potentially explain the annual recruitment were evaluated. Hypothesis 1: high precipitation shifts the salinity front northward, resulting in favorable spawning locations. Hypothesis 2: a southward shift of the position of the North Equatorial Current (NEC bifurcation provides a favorable larval transport route. Hypothesis 3: ocean conditions (eddy activities and productivity along the larval migration route influence larval survival. Results of time series regression and wavelet analyses suggest that Hypothesis 1 is not supported, as the glass eel catches exhibited a negative relationship with precipitation. Hypothesis 2 is plausible. However, the catches are correlated with the NEC bifurcation with a one-year lag. Considering the time needed for larval transport (only four to six months, the one-year lag correlation does not support the direct transport hypothesis. Hypothesis 3 is supported indirectly by the results. Significant correlations were found between catches and climate indices that affect ocean productivity and eddy activities, such as the Quasi Biennial Oscillation (QBO, North Pacific Gyre Oscillation (NPGO, Pacific Decadal Oscillation (PDO, and Western Pacific Oscillation (WPO. Wavelet analysis reveals three periodicities of eel catches: 2.7, 5.4, and 10.3 years. The interannual coherence with QBO and the Niño 3.4 region suggests that the shorter-term climate variability is modulated zonally by equatorial dynamics. The low-frequency coherence with WPO, PDO, and NPGO demonstrates the decadal modulation of meridional teleconnection via ocean-atmosphere interactions. Furthermore, WPO and QBO are linked to solar activities. These results imply that the Japanese eel recruitment may be influenced by multi-timescale climate variability. Our findings call for investigation of extra-tropical ocean dynamics that affect survival of eels during transport, in addition to the existing efforts to study the equatorial system.

  2. Cardio-respiratory Physiology of the European Eel (Agunilla anguilla) in Extreme Environments

    DEFF Research Database (Denmark)

    Methling, Caroline

    , while eels exposed to oscillating CO2 partial pressures (20-60mmHg) had a reduced post-prandial ammonia excretion. This suggests that depending on the specific conditions, hypercapnia may limit the appetite and feed intake as it takes longer time to process a meal, and/or that a smaller amount...... and thus ensure adequate cardiac performance when diving to cooler depths. Furthermore, the individual contribution of three different sarcolemmal Ca2+ channels (L-type, NCX and SOCE) to the generation of force also depended on ambient temperature. Elevations in CO2 partial pressure (hypercapnia...

  3. 2011 NOAA Ortho-rectified Mosaic of Anguilla Harbor, St. Croix, U.S. Virgin Islands (NODC Accession 0086076)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains ortho-rectified mosaic tiles, created as a product from the NOAA Integrated Ocean and Coastal Mapping (IOCM) initiative. The source imagery...

  4. PENGARUH PENGGUNAAN TEPUNG SILASE DAUN MENGKUDU (Morinda citrifolia) DALAM FORMULA PAKAN TERHADAP PERTUMBUHAN IKAN SIDAT (Anguilla bicolor) STADIA ELVER

    OpenAIRE

    Dewi Cholifah; Mivida Febriani; Ekawati, Arning W; Yenny Risjani

    2012-01-01

    Penelitian ini dilakukan untuk mengetahui pengaruh dan dosis terbaik penggunaan tepung silase daun Mengkudu (M. citrifolia) dalam formula pakan terhadap pertumbuhan ikan Sidat (A. bicolor) stadia elver. Penelitian dibagi menjadi dua tahap, tahap pertama formulasi pakan percobaan, dan tahap kedua uji in vivo/uji formula pakan percobaan skala laboratorium pada ikan Sidat. Pelaksanaan penelitian tahap 1 adalah membuat formula pakan iso protein (40% ) dan iso energi (3.600 kkal/kg pakan) dengan m...

  5. Three nuclear and two membrane estrogen receptors in basal teleosts, Anguilla sp.: Identification, evolutionary history and differential expression regulation

    DEFF Research Database (Denmark)

    Lafont, Anne Gaëlle; Rousseau, Karine; Tomkiewicz, Jonna;

    2016-01-01

    teleosts. Phylogeny and synteny analyses suggest that they result from teleost whole genome duplication (3R). In contrast to conserved 3R-duplicated ESR2 and GPER, one of 3R-duplicated ESR1 has been lost shortly after teleost emergence. Quantitative PCRs revealed that the five receptors are all widely...

  6. All in the ears: unlocking the early life history biology and spatial ecology of fishes.

    Science.gov (United States)

    Starrs, Danswell; Ebner, Brendan C; Fulton, Christopher J

    2016-02-01

    Obtaining biological and spatial information of the early life history (ELH) phases of fishes has been problematic, such that larval and juvenile phases are often referred to as the 'black box' of fish population biology and ecology. However, a potent source of life-history data has been mined from the earstones (otoliths) of bony fishes. We systematically reviewed 476 empirical papers published between 2005 and 2012 (inclusive) that used otoliths to examine fish ELH phases, which has been an area of increasing attention over this period. We found that otolith-based research during this period could be split into two broad themes according to whether studies examined: (i) biological objectives related to intrinsic processes such as larval and juvenile age, growth and mortality, and/or (ii) spatial objectives, such as habitat use, dispersal and migration. Surprisingly, just 24 studies (5%) explored a combined biological-spatial objective by simultaneously exploiting biological and spatial information from otoliths, suggesting much more scope for such integrated research objectives to be answered via the use of multiple otolith-based techniques in a single study. Mapping otolith analytical techniques across these two approaches revealed that otolith structural analysis was mainly used to investigate biological processes, while otolith chemical analyses were most often applied to spatial questions. Heavy skew in research effort was apparent across biomes, with most (62%) publications specific to marine species, despite comparable levels of species richness and the importance of freshwater taxa (just 15% of papers). Indeed, around 1% (380 species) of a possible 31400+ extant species were examined in our surveyed papers, with a strong emphasis on temperate marine species of commercial value. Potential model species for otolith-based ELH ecology research are arising, with the eel genus Anguilla (24 studies) and the European anchovy Engraulis encrasicolis (14 studies

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

    Science.gov (United States)

    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

  8. Effects of lead, molybdenum, rubidium, arsenic and organochlorines on spermatogenesis in fish: monitoring at Mekong Delta area and in vitro experiment.

    Science.gov (United States)

    Yamaguchi, Sonoko; Miura, Chiemi; Ito, Aki; Agusa, Tetsuro; Iwata, Hisato; Tanabe, Shinsuke; Tuyen, Bui Cach; Miura, Takeshi

    2007-06-05

    To estimate the influence of water contaminants on fish reproduction in the Mekong Delta area, we sampled cultivated male catfish (Pangasianodon hypophthalmus), investigated testicular development, and measured persistent organic pollutants (POPs) and trace element levels in muscle and liver, respectively. Various testes sizes were observed although sampling took place during a short period. Histological analysis revealed that all developmental stages of germ cells were observed in catfish with large testis, whereas only necrotic spermatogonia but no other germ cells were observed in catfish with small testis. In small testis, furthermore, vacuolization and hypertrophy of Sertoli cells were observed. Measurement of POPs in muscle and trace elements in liver demonstrated that there were negative correlations between GSI and the concentrations of Pb, Mo, Rb and As. To clarify possible direct effects of Pb, Mo, Rb and As on spermatogenesis in fish, we investigated the effects of these trace elements on spermatogenesis using in vitro testicular organ culture of Japanese eel (Anguilla japonica). Treatment with each of the trace elements alone did not affect spermatogenesis. However, treatment with 10(-7)M of Pb, 10(-5) and 10(-4)M of Mo, 10(-5)-10(-3)M of Rb or 10(-5)M of As inhibited the spermatogenesis induced by 11-ketotestosterone (11KT). Furthermore, treatment with 10(-4)M of As in combination with 11KT caused necrosis of testicular fragments. Taken together, these results are consistent with the hypothesis that Pb, Mo, Rb and As can exert inhibitory effects on spermatogenesis in catfish inhabiting the Mekong Delta area.

  9. Effects of lead, molybdenum, rubidium, arsenic and organochlorines on spermatogenesis in fish: Monitoring at Mekong Delta area and in vitro experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Sonoko [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Miura, Chiemi [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Ito, Aki [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan); Agusa, Tetsuro [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Iwata, Hisato [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577 (Japan); Bui Cach Tuyen [Nong Lam University, Thu Duc Distr., Ho Chi Minh City (Viet Nam); Miura, Takeshi [Laboratory of Fish Reproductive Physiology, Ehime University, Matsuyama, Ehime 790-8566 (Japan)]. E-mail: miutake@agr.ehime-u.ac.jp

    2007-06-05

    To estimate the influence of water contaminants on fish reproduction in the Mekong Delta area, we sampled cultivated male catfish (Pangasianodon hypophthalmus), investigated testicular development, and measured persistent organic pollutants (POPs) and trace element levels in muscle and liver, respectively. Various testes sizes were observed although sampling took place during a short period. Histological analysis revealed that all developmental stages of germ cells were observed in catfish with large testis, whereas only necrotic spermatogonia but no other germ cells were observed in catfish with small testis. In small testis, furthermore, vacuolization and hypertrophy of Sertoli cells were observed. Measurement of POPs in muscle and trace elements in liver demonstrated that there were negative correlations between GSI and the concentrations of Pb, Mo, Rb and As. To clarify possible direct effects of Pb, Mo, Rb and As on spermatogenesis in fish, we investigated the effects of these trace elements on spermatogenesis using in vitro testicular organ culture of Japanese eel (Anguilla japonica). Treatment with each of the trace elements alone did not affect spermatogenesis. However, treatment with 10{sup -7} M of Pb, 10{sup -5} and 10{sup -4} M of Mo, 10{sup -5}-10{sup -3} M of Rb or 10{sup -5} M of As inhibited the spermatogenesis induced by 11-ketotestosterone (11KT). Furthermore, treatment with 10{sup -4} M of As in combination with 11KT caused necrosis of testicular fragments. Taken together, these results are consistent with the hypothesis that Pb, Mo, Rb and As can exert inhibitory effects on spermatogenesis in catfish inhabiting the Mekong Delta area.

  10. Phosphorus-nitrogen loading and trend of fish catch as index of lake Mariut eutrophication.

    Science.gov (United States)

    Thomas, G H; el-Karyony, I A; Hassan, A H

    1993-01-01

    Lake Mariut was considered in the past to represent an important source of fish production in Alexandria especially during the periods which were characterized by low catch from its marine fisheries. The growing population in Alexandria and the expanding industries around the lake were accompanied with increased quantities of domestic and industrial wastes discharged annually into the lake proper. These quantities were increased from 192 million cubic meters in 1974 to about 300 million cubic meters in 1992. Consequently, the water quality in this basin was highly deteriorated and changed to become markedly eutrophic. High input of nutrients through sewage and industrial wastes has considerably increased the phosphorus and nitrogen load in the lake proper. Phosphorus and nitrogen loading in this basin were estimated in 1992 to be 60.2 gm/m3 P/y and 79.8 gm/m3 N/y. According to the nutrient concept given by Vollenweider (1974), these two figures have provided an evidence that the lake proper was strongly changed from oligotrophic to polytrophic phase. The trend of its total fish catch as well as the trend of different fish categories catch during the period 1970-1992 also confirms its eutrophication. This is in addition to bad changes that took place with respect to environmental conditions due to the continuous inflow of domestic and industrial wastes from different sources into this part of Mariut lake. Marginal increments of the lake proper total catch were decreased from 20.6% in 1970 to -28.8% in 1992, while the marginal increments of Tilapia sp., Clarias sp, Anguilla sp. and Mugil sp. were decreased from 21.4%, 14.3%, 29.8%, and 28.9% respectively in 1970 to -29.1%, -25.3%, -43.0%, and -36.8% in 1992. Based on these two indices of the lake proper eutrophication, the expected improvement of its environmental conditions will take several years after treating all inland discharges flowing into the lake and/or diverting all relevant outfalls away from this basin.

  11. Complete genome sequence of Vibrio anguillarum phage CHOED successfully used for phage therapy in aquaculture

    DEFF Research Database (Denmark)

    Romero, Jaime; Higuera, Gastón; Gajardo, Felipe

    2014-01-01

    Vibrio anguillarum phage CHOED was isolated from Chilean mussels. It is a virulent phage showing effective inhibition of V. anguillarum. CHOED has potential in phage therapy, because it can protect fish from vibriosis in fish farms. Here, we announce the completely sequenced genome of V. anguilla...

  12. Evaluation of surgical implantation of electronic tags in European eel and effects of different suture materials

    DEFF Research Database (Denmark)

    Thorstad, Eva B.; Økland, Finn; Westerberg, Håkan

    2013-01-01

    Effects of implanting data-storage tags in European eel, Anguilla anguilla, and the suitability of different suture materials (braided permanent silk, permanent monofilament, absorbable and absorbable antibacterial) were examined. The tags consisted of an electronic unit and three floats on a wire....... Antibacterial treatment had no effect on inflammation or healing rates. After 6 months, the tag started to become expelled through the incision in five fish (12%). The internal reaction appeared stronger around the floats, suggesting that the coating material of the floats created a tissue reaction, which...

  13. Fishing

    Institute of Scientific and Technical Information of China (English)

    姜群山

    2002-01-01

    @@ Last Saturday my cousin (表兄) came to my home. We were very happy to see each other. We decided that the next day we went to fish. We got up very early that day. When we left home,the moon could still be seen in the sky.

  14. Development and validation of a real-time PCR assay for the detection of anguillid herpesvirus 1

    NARCIS (Netherlands)

    van Beurden, S J; Voorbergen-Laarman, M A; Roozenburg, I; van Tellingen, J; Haenen, O L M; Engelsma, M Y

    2015-01-01

    Anguillid herpesvirus 1 (AngHV1) causes a haemorrhagic disease with increased mortality in wild and farmed European eel, Anguilla anguilla (L.) and Japanese eel Anguilla japonica, Temminck & Schlegel). Detection of AngHV1 is currently based on virus isolation in cell culture, antibody-based typing a

  15. Development and validation of a real-time PCR assay for the detection of anguillid herpesvirus 1

    NARCIS (Netherlands)

    Beurden, van S.J.; Voorbergen-Laarman, H.A.; Roozenburg-Hengst, R.E.M.; Tellingen, van Jurjen; Haenen, O.L.M.; Engelsma, M.Y.

    2016-01-01

    Anguillid herpesvirus 1 (AngHV1) causes a haemorrhagic disease with increased mortality in wild and farmed European eel, Anguilla anguilla (L.) and Japanese eel Anguilla japonica, Temminck & Schlegel). Detection of AngHV1 is currently based on virus isolation in cell culture, antibody-based typi

  16. Ultrastructural characters of the spermatozoa in Digeneans of the genus Lecithochirium Lühe, 1901 (Digenea, Hemiuridae, parasites of fishes: comparative study of L. microstomum and L. musculus

    Directory of Open Access Journals (Sweden)

    Ndiaye Papa Ibnou

    2014-01-01

    Full Text Available This study provides the first ultrastructural data of spermatozoa in the genus Lecithochirium. The spermatozoa of L. microstomum (from Trichiurus lepturus in Senegal and L. musculus (from Anguilla anguilla in Corsica exhibit the general pattern described in the great majority of the Digenea, namely two axonemes with the 9 + “1” pattern typical of the Trepaxonemata, one mitochondrion, a nucleus, parallel cortical microtubules and external ornamentation of the plasma membrane. Spermatozoa of L. microstomum and L. musculus have some specific features such as the presence of a reduced number of cortical microtubules arranged on only one side of the spermatozoon, the lack of spine-like bodies and expansion of the plasma membrane. The external ornamentation of the plasma membrane entirely covers the anterior extremity of the spermatozoa. The ultrastructure of the posterior extremity of the spermatozoa corresponds to the pattern previously described in the Hemiuridae, characterized by only singlets of the second axoneme. A particularity of these spermatozoa is the organization of the microtubule doublets of the second axoneme around the nucleus in the posterior part of the spermatozoon.

  17. Effect of TBT and PAHs on CYP1A, AhR and Vitellogenin Gene Expression in the Japanese Eel, Anguilla japonica.

    Science.gov (United States)

    Choi, Min Seop; Kwon, Se Ryun; Choi, Seong Hee; Kwon, Hyuk Chu

    2012-12-01

    Gene expressions of cytochrome P4501A (CYP1A), aryl hydrocarbon receptor (AhR) and vitellogenin (Vg) by endocrine disruptors, benzo[α]pyrene (B[a]P) and tributyltin (TBT) were examined in cultured eel hepatocytes which were isolated from eels treated previously with B[a]P (10 mg/kg) or estradiol-17β (20 mg/kg) in vivo, and the relationship between CYP1A, AhR and Vg genes were studied. When the cultured eel hepatocytes were treated with B[a]P (10(-6)-10(-5) M) the gene expressions of CYP1A and AhR were enhanced in a concentration-dependent manner. However, when treated with TBT (10(-9)-10(-5) M) the gene expressions of CYP1A and AhR were suppressed at high concentrations (10(-6)-10(-5) M), while having no effects at low concentrations (10(-9)-10(-7) M). Gene expression of Vg was also suppressed by TBT in a concentration-dependent manner in cultured eel hepatocytes which was previously treated in vivo with estradiol-17β.

  18. Potential interactions between diadromous fishes of U.K. conservation importance and the electromagnetic fields and subsea noise from marine renewable energy developments.

    Science.gov (United States)

    Gill, A B; Bartlett, M; Thomsen, F

    2012-07-01

    The considerable extent of construction and operation of marine renewable energy developments (MRED) within U.K. and adjacent waters will lead, among other things, to the emission of electromagnetic fields (EMF) and subsea sounds into the marine environment. Migratory fishes that respond to natural environmental cues, such as the Earth's geomagnetic field or underwater sounds, move through the same waters that the MRED occupy, thereby raising the question of whether there are any effects of MRED on migratory fishes. Diadromous species, such as the Salmonidae and Anguillidae, which undertake large-scale migrations through coastal and offshore waters, are already significantly affected by other human activities leading to national and international conservation efforts to manage any existing threats and to minimize future concerns, including the potential effect of MRED. Here, the current state of knowledge with regard to the potential for diadromous fishes of U.K. conservation importance to be affected by MRED is reviewed. The information on which to base the review was found to be limited with respect to all aspects of these fishes' migratory behaviour and activity, especially with regards to MRED deployment, making it difficult to establish cause and effect relationships. The main findings, however, were that diadromous species can use the Earth's magnetic field for orientation and direction finding during migrations. Juveniles of anadromous brown trout (sea trout) Salmo trutta and close relatives of S. trutta respond to both the Earth's magnetic field and artificial magnetic fields. Current knowledge suggests that EMFs from subsea cables may interact with migrating Anguilla sp. (and possibly other diadromous fishes) if their movement routes take them over the cables, particularly in shallow water (fishes are likely to encounter EMFs from subsea cables either during the adult movement phases of life or their early life stages during migration within shallow

  19. [The Wormicidal Substances Of Fresh Water Fishes On Clonorchis Sinensis: II. Preliminary Research On The Wormicidal Substances From Mucous Substances Of Various Fresh Water Fishes

    Science.gov (United States)

    Rhee, Jae Ku; Baek, Byeong Kirl; Ahn, Byung Zun; Park, Young Jun

    1980-06-01

    The present work which was investigated in July 1979, was to observe the wormicidal effects of the external mucous substances of 9 species of fresh water fishes (Cyprinus carpio, Parasilurus asotus, Anguilla japonica, Ophicephalus argus, Carassius carassius; golden crusian carp, Misgurnus anguillicaudatus, Zacco platypus, Pseudorasbora parva and Carassius carassius; crusian carp) on cercaria, liberated metacercaria and adult of Clonorchis sinensis. The mucous substances extracted by ether from the above 9 species of fishes were separated into many spots on the silica gel thin layer chromatography, and divided into many fractions in the silica gel column chromatography which used petroleum ether (30%) and chloroform (70%) as a solvent. 1. On the silica gel thin layer chromatography of ether extracts from 9 species of fresh water fishes, each of the Rf. values which had wormicidal effect on the cercaria of C. sinensis were different from others; Rf. value of C. carassius (crusian carp) was 0.937, 0.709 in O. argus, 0.612 in A. japonica, 0.576 in P. asotus, 0.451 in C. carpio, 0.701 in Z. platypus, 0.385 in C. carassius(golden crusian carp) and 0.15 in P. parva. Time for wormicide was different from each other, too. It took 14 min. in a case of C. carassius(crusian carp), 25 min. in Z. platypus, 26 min. in C. carassius(golden crusian carp), 28 min. in C. carpio, 30 min. in P. asotus, 35 min. in O. argus, 40 min. P. parva and 180 min. in A. japonica. But any of the spots of M. anguillicaudatus did not show wormicidal effect on the cercaria within 10 hours. 2. In the silica gel column chromatography of ether extracts from 9 species of fresh water fishes, the fractions which had wormicidal effect on the metacercaria of C. sienesis were different from each other; in a case of C. carassius(crusian carp), the first fraction only had wormicidal effect, the 2nd in P. asotus, the 3rd in O. argus, the 4th in C. carassius(golden crusian carp), the 2nd in C. carpio and the 4th in

  20. Distribution and Habitat Preferences of the Introduced Mummichog Fundulus heteroclitus(Linneaus) in South-western Spain

    Science.gov (United States)

    Gutiérrez-Estrada, J. C.; Prenda, J.; Oliva, F.; Fernández-Delgado, C.

    1998-06-01

    The distribution and apparent habitat preference of the common mummichog ( Fundulus heteroclitus) in south-western Spain were examined during summer-autumn 1996. This introduced species was more or less continuously distributed along the Atlantic coast of Spain, being more abundant in sites near the coastline (usually salinities >25. It was the most frequently captured fish species, occurring at 81 of the 272 sites sampled; their frequency of occurrence was almost twice that of the second ranked species ( Gambusia holbrooki). However, in over 80% of cases, F. heteroclituswas found alone or with only one sympatric fish species, which usually belonged to a group composed of Gobius niger,mugilids, Anguilla anguilla, Blenniussp., Lebias ibera, Pomatoschistussp. and Dicentrarchus labrax. Finally, the origin and dispersal of mummichog in the Iberian peninsula and the potential effects of this species on native fish populations is discussed.

  1. Évaluation de l'âge et de la croissance de l'anguille européenne (Anguilla anguilla L. en milieu continental : méthodologies, validation, application en Méditerranée et comparaisons en Europe

    Directory of Open Access Journals (Sweden)

    PANFILI J.

    1994-10-01

    Ces variabilités interviennent directement sur la croissance des individus. Les croissances individuelles dans les milieux méditerranéens saumâtre et dulçaquicole ont été mesurées et comparées entre elles et avec la littérature. La croissance en milieu saumâtre est nettement plus importante que celle en milieu d'eau douce.

  2. Ovogenèse chez l'Anguille (Anguilla anguilla L. : ultrastructure de l'ovaire à différents stades de développement et implication des lipoprotéines au cours de la vitellogenèse

    Directory of Open Access Journals (Sweden)

    BURZAWA-GERARD E.

    1994-10-01

    Full Text Available Dans les eaux douces, l'anguille est présente à deux stades de développement : le stade jaune où l'animal se nourrit et assure sa croissance et le stade argenté où il jeûne et se prépare à la migration de reproduction. Ce cycle est particulièrement intéressant pour l'étude des régulations hormonales de l'ovogénèse et en particulier celle de la vitellogenèse, étape pendant laquelle l'ovocyte incorpore la vitellogénine pour former le vitellus. Cet article décrit, d'une part, les différents critères de la vitellogenèse disponibles chez l'anguille (caractérisation des lipoprotéines, ultrastructure des ovocytes, teneurs plasmatiques des stéroïdes sexuels et de la vitellogénine, caractérisation des récepteurs hépatiques de l'oestradiol (RE2 et, d'autre part, l'effet de traitements gonadotropes ou stéroïdiens sur ces critères pour dégager la nature des contrôles endocriniens impliqués au cours de la vitellogenèse. Les lipoprotéines présentes dans le plasma de l'anguille jaune ou argentée sont les VLDL (lipoprotéine de très faible densité et les HDL (lipoprotéine de haute densité ; les LDL (lipoprotéine de faible densité ne sont pas trouvées. Des modifications des apolipoprotéines présentes dans les lipoprotéines de haute densité (HDL sont observées au cours de l'argenture. Par des traitements à l'oestradiol, les VLDL augmentent considérablement ; il apparaît aussi une classe nouvelle de lipoprotéines, les VHDL (lipoprotéine de très haute densité ou vitellogénine. L'analyse de l'ultrastructure ovocytaire montre que l'anguille jaune est prévitellogénique en raison de l'absence des structures ovocytaires spécifiques de l'endocytose ; elles sont présentes chez l'anguille argentée qui est donc vitellogénique. In vivo chez l'anguille jaune, après un mois de traitement gonadotrope, une augmentation de l'oestradiol (E2 plasmatique est observée sans apparition de vitellogénine circulante. Toutefois, si les traitements sont prolongés, la vitellogenèse s'amorce. Chez l'anguille argentée, la vitellogenèse est induite dès la deuxième semaine. La testostérone puis l'oestradiol augmente dans le plasma ainsi que la vitellogénine. Ce résultat suggère un rôle des androgènes dans l'induction hépatique de la vitellogenèse. Les études in vitro sur les hépatocytes d'anguille maintenus en culture primaire ont mis en évidence la compétence des oestrogènes et des androgènes à stimuler la synthèse de vitellogénine. Un effet amplificateur de l'hormone de croissance bovine (bGH sur la synthèse de vitellogénine par des doses faibles de E2 a été mis en évidence in vivo et in vitro, suggérant une action directe de la GH sur le foie. Les récepteurs hépatiques de l'oestradiol (RE2 ont été caractérisés ; ils s'apparentent à la famille des récepteurs nucléaires des stéroïdes. Ils sont présents en quantité très faible dans le foie de l'anguille jaune ou argentée. Les premiers résultats obtenus suggèrent que l'action de la GH pourrait être associée à une synthèse de RE2 dans le foie. Des différences dans l'induction de la vitellogenèse par la gonadotropine de carpe sont mises en évidence entre les anguilles jaunes et argentées. Il semble que différentes lipoprotéines participent à l'élaboration du vitellus. L'induction et le contrôle de la vitellogenèse sont plurihormonaux.

  3. Étude des variations de paramètres anatomiques et endocriniens chez l'anguille européenne (Anguilla anguilla femelle, sédentaire et d'avalaison : application à la caractérisation du stade argenté

    Directory of Open Access Journals (Sweden)

    MARCHELIDON J.

    1999-07-01

    En conclusion, l'argenture inclut des transformations multiples, caractéristiques aussi bien de la métamorphose (augmentation de T4 , de l'initiation de la puberté (augmentations du RGS et de GtH, du jeûne (diminution du RTDS et de l'arrêt de croissance (diminution de GH. Certains paramètres anatomiques (IO, RGS, RTDS, et endocriniens (GtH, qui présentent très peu de recoupement dans les valeurs individuelles entre les stades jaune et argenté, sont utilisables comme critères de l'argenture.

  4. Qualitative assessment of the diet of European eel larvae in the Sargasso Sea resolved by DNA barcoding

    DEFF Research Database (Denmark)

    Riemann, L.; Alfredsson, H.; Hansen, Michael Møller

    2010-01-01

    European eels (Anguilla anguilla) undertake spawning migrations of more than 5000 km from continental Europe and North Africa to frontal zones in the Sargasso Sea. Subsequently, the larval offspring are advected by large-scale eastward ocean currents towards continental waters. However, the Sarga......European eels (Anguilla anguilla) undertake spawning migrations of more than 5000 km from continental Europe and North Africa to frontal zones in the Sargasso Sea. Subsequently, the larval offspring are advected by large-scale eastward ocean currents towards continental waters. However...

  5. Analyse de la biodiversité et de la production ichtyques dans trois lacs nord Africains : Merja Zerga (Maroc), Garâat Ichkeul (Tunisie) et lac Edku (Egypte).

    OpenAIRE

    Abdelzaher, H. M. A.; Ramdani, M.; Flower, R.; Kraiem, M. M.; A. A. Fathi

    2003-01-01

    This survey first presents an inventory of fish species in the three studied sites. Altogether 17 fish species were found in Merja Zerga (Morocco), 25 species in Garâat Ichkeul and 16 species in Edku lagoon. Three fish groups live in these brackish lakes : sedentary fish, marine fish and freshwater fish. The second part of the study deals with the production of the different species. This production mainly rests upon Mugilidae and Anguilla in Merja Zerga and Ichkeul, while, in Edku, Tilapia...

  6. Histopathological changes induced by environmental stress in common carp, Japanese coloured carp, European eel, and African catfish.

    Science.gov (United States)

    Szakolczai, J

    1997-01-01

    Histopathological changes caused by stress during catching and transport were examined in four fish species, the common carp (Cyprinus carpio), the Japanese coloured carp (koi, the coloured variant of the Asian carp, Cyprinus carpio haematopterus), the European eel (Anguilla anguilla), and the African catfish (Clarias gariepinus). In all species, the goblet cells of the gills and skin were decreased in number and slight detachment of the epithelium of the secondary gill lamellae was seen. Loss of goblet cells and detachment of the columnar epithelial cells were found in the intestinal mucosa of common carp and coloured carp. It is supposed that these lesions may affect ion transport and respiration in the gills and disturb normal intestinal function, thus serving as a starting point for different diseases.

  7. Use of speleologic data to evaluate Holocene uplifting and tilting: an example from the Frasassi anticline (northeastern Apennines, Italy)

    NARCIS (Netherlands)

    Mariani, S.; Mainiero, M.; Barchi, M.; van der Borg, K.; Vonhof, H.B.; Montanari, A.

    2007-01-01

    Deep inside the Frasassi cave complex in the foreland fold and thrust belt of the northeastern Apennines (central Italy), the remains of hundreds of eels (Anguilla anguilla) are found scattered on the shores of phreatic lakes up to 5 m above the water table. These sub-fossil eels, and the speleothem

  8. Impact of eel viruses on recruitment of European eel

    NARCIS (Netherlands)

    Haenen, O.L.M.; Ginneken, van V.J.T.; Engelsma, M.Y.; Thillart, G.E.E.J.M.

    2009-01-01

    Eels have an uncommon catadromic life cycle with exceptional migratory patterns to their spawning grounds several thousand kilometres away: the European eel (Anguilla anguilla) travels over 5,500 km to the Sargasso Sea (Schmidt 1923; McCleave and Kleckner 1987; Tesch 1982; Tesch and Wegner 1990); th

  9. Impact of eel viruses on recruitment of European eel

    NARCIS (Netherlands)

    Haenen, O.L.M.; Ginneken, van V.J.T.; Engelsma, M.Y.; Thillart, G.E.E.J.M.

    2009-01-01

    Eels have an uncommon catadromic life cycle with exceptional migratory patterns to their spawning grounds several thousand kilometres away: the European eel (Anguilla anguilla) travels over 5,500 km to the Sargasso Sea (Schmidt 1923; McCleave and Kleckner 1987; Tesch 1982; Tesch and Wegner 1990);

  10. NOAA Integrated Ocean and Coastal Mapping (IOCM) orthorectified mosaic image tiles for Christiansted, St. Johns and Anguilla Harbor, St. Croix, U.S. Virgin Islands, 2011 (NODC Accession 0086076)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains ortho-rectified mosaic tiles, created as a product from the NOAA Integrated Ocean and Coastal Mapping (IOCM) initiative. The images were...

  11. INDUCED GONADAL MATURATION BY SINGLE IMPLANTATION OF ANDROSTENEDIONE IN MALE Anguilla japonic%埋植雄烯二酮一次诱导雄性日本鳗鲡性腺发育成熟的研究

    Institute of Scientific and Technical Information of China (English)

    邓岳松; 林浩然

    2000-01-01

    埋植雄烯二酮包膜型药条一次后70d,塘养雄鳗成熟率达73.3%.鳗鲡精液质量随埋植天数的增加逐步提高;脑垂体促性腺激素(GtH)含量在埋植后有明显升高;血清GtH含量在埋植后15d起,一直稳定在2ng/ml左右,与对照组(约0.9ng/ml)相比有显著提高.

  12. Fish Allergy

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Fish Allergy KidsHealth > For Parents > Fish Allergy Print A ... From Home en español Alergia al pescado About Fish Allergy A fish allergy is not exactly the ...

  13. To boldly climb: behavioural and cognitive differences in migrating European glass eels.

    Science.gov (United States)

    Podgorniak, T; Blanchet, S; De Oliveira, E; Daverat, F; Pierron, F

    2016-01-01

    European eel (Anguilla anguilla) is a catadromous fish species that received substantial attention as its population has markedly declined in the last three decades. The possible causes of this decline include habitat fragmentation factors such as dams and weirs. In some cases, these obstacles are equipped with fish friendly passage devices that may select young eels according to their climbing behaviour. We tested how individual climbing tendency was related to the event of fishway passage experienced in the field and classified fish climbing profiles as climbing 'leaders', 'followers', 'finishers' and 'no climbers'. Moreover, we analysed the brain transcription level of genes related to neurogenesis and synaptic plasticity and compared it to climbing profiles. We found that fish from the upstream segments of an impounded river had a higher climbing propensity. Their behaviour was also more repeatable throughout the whole test than the obstacle-naive fish from the downstream segment. Moreover, we found that boldly climbing 'leaders' had lower levels of transcription of synapse-related genes than the climbing 'followers'. These differences could be related to coping styles of fish, where proactive 'leaders' express a routine and risky behaviour, whereas reactive fish need an environmental assessment before exploratory behaviour. Our study showed that differences in climbing propensity exist in glass eels separated by water obstacles. Moreover, eels could adopt climbing different strategies according to the way they deal with environmental stress and to the cognitive abilities they possess.

  14. Fish Hearing.

    Science.gov (United States)

    Blaxter, J. H. S.

    1980-01-01

    Provides related information about hearing in fish, including the sensory stimulus of sound in the underwater environment, mechanoreceptors in fish, pressure perception and the swimbladder, specializations in sound conduction peculiar to certain fish families. Includes numerous figures. (CS)

  15. Fish Allergy

    Science.gov (United States)

    ... in a clear and consistent manner, so that consumers with food allergies and their caregivers can be informed as ... the menu, cross-contact with fish is possible. Ethnic ... fish. Avoid foods like fish sticks and anchovies. Some individuals with ...

  16. First detection of Mnemiopsis leidyi (Ctenophora, Bolinopsidae in Sardinia (S’Ena Arrubia Lagoon, Western Mediterranean: a threat for local fishery and species recruitment

    Directory of Open Access Journals (Sweden)

    R. DICIOTTI

    2016-07-01

    Full Text Available The invasive comb jelly Mnemiopsis leidyi is a lobate ctenophore native of coastal and estuarine waters of the temperate western Atlantic Ocean. In the last decades this species has expanded its range of distribution, colonizing marine and transitional environments in Europe. In October 2015, during a survey fishing the European eel Anguilla anguilla in Sardinia (western Mediterranean, a massive bloom of this specie was observed in the eutrophic S’Ena Arrubia Lagoon for the first time. In November 2015, sampling was conducted at three stations in the lagoon and in a fyke net, in order to estimate the abundance of M. leidyi and to determine its impact on the fishing activity. The results showed an abundance of 2.83 ctenophores m-3. Specimens were all adults, measuring 18 - 62 mm total length. The abundant number of ctenophores (6837 individuals per fyke net damaged fishing operations, reducing catches and affecting the performance of fishing gears. Since there is no effective mechanical, chemical or biological method to counter M. leidyi, the short term economic damage may be approached by new management measures of fisheries. In addition, other actions against the recurring of M. leidyi invasion, can include management strategies, in particular those finalized to reduce the high trophic state of the lagoon.

  17. Fish allergy and fish allergens

    DEFF Research Database (Denmark)

    Kuehn, A; Hilger, Christiane; Ollert, Markus

    2016-01-01

    but patients with this phenotype constitute an important sub-group among fish-allergic individuals. 2. Newly identified fish allergens, enolases, aldolases, and fish gelatin, are of high relevance as the majority of the fish-allergic individuals seem to develop specific IgE against these proteins. The present...

  18. Surface Geology of the Caribbean Region (geo6bg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset includes polygons that describe the geologic age of surface outcrops of bedrock of the Caribbean region (Anguilla, Antigua and Barbuda, Aruba, Bahamas,...

  19. Faults of the Caribbean Region (flt6bg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset describes faults and structural features of the Caribbean region (Anguilla, Antigua and Barbuda, Aruba, Bahamas, Barbados, Belize, British Virgin...

  20. Farming different species in RAS in Nordic countries: Current status and future perspectives

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Lund, Ivar; Thorarinsdottir, Ragnheidur

    2013-01-01

    (Oncorhynchus mykiss), European eel (Anguilla anguilla), pike perch (Stizostedion lucioperca), Arctic char (Salvelinus alpinus), sturgeon (order Acipenseriformes), Nile tilapia (Oreochromis niloticus), and European lobster (Homarus gammarus). High capital costs are one of the biggest challenges to sustainable...... RAS calling for large scale intensive productions to reduce investment -and operation costs. Consistent with this, production of Atlantic salmon smolts in indoor RAS and rainbow trout in outdoor Model-Trout-Farms (MTFs) have been the commercially most successful productions so far. Aside from end...

  1. Antarctic Fishes.

    Science.gov (United States)

    Eastman, Joseph T.; DeVries, Arthur L.

    1986-01-01

    Explains the adaptations to Antarctic waters that Notothenioidei, a group of advanced bony fishes, have exhibited. Discusses the fishes' mechanisms of production of antifreeze properties and their capacities for neutral buoyancy in water. (ML)

  2. Identification and localization of the structural proteins of anguillid herpesvirus 1

    Directory of Open Access Journals (Sweden)

    van Beurden Steven J

    2011-10-01

    Full Text Available Abstract Many of the known fish herpesviruses have important aquaculture species as their natural host, and may cause serious disease and mortality. Anguillid herpesvirus 1 (AngHV-1 causes a hemorrhagic disease in European eel, Anguilla anguilla. Despite their importance, fundamental molecular knowledge on fish herpesviruses is still limited. In this study we describe the identification and localization of the structural proteins of AngHV-1. Purified virions were fractionated into a capsid-tegument and an envelope fraction, and premature capsids were isolated from infected cells. Proteins were extracted by different methods and identified by mass spectrometry. A total of 40 structural proteins were identified, of which 7 could be assigned to the capsid, 11 to the envelope, and 22 to the tegument. The identification and localization of these proteins allowed functional predictions. Our findings include the identification of the putative capsid triplex protein 1, the predominant tegument protein, and the major antigenic envelope proteins. Eighteen of the 40 AngHV-1 structural proteins had sequence homologues in related Cyprinid herpesvirus 3 (CyHV-3. Conservation of fish herpesvirus structural genes seemed to be high for the capsid proteins, limited for the tegument proteins, and low for the envelope proteins. The identification and localization of the structural proteins of AngHV-1 in this study adds to the fundamental knowledge of members of the Alloherpesviridae family, especially of the Cyprinivirus genus.

  3. Fish Dishes.

    Science.gov (United States)

    Derby, Marie

    2003-01-01

    Describes an art project that was inspired by Greek pottery, specifically dishes shaped as fish. Explains that fourth-grade students drew a fish shape that was later used to create their clay version of the fish. Discusses how the students examined the pottery to make decisions about color and design. (CMK)

  4. Experimental infection and detection of Aphanomyces invadans in European catfish, rainbow trout and European eel.

    Science.gov (United States)

    Oidtmann, Birgit; Steinbauer, Peter; Geiger, Sheila; Hoffmann, Rudolf W

    2008-12-22

    European catfish Silurus glanis, European eel Anguilla anguilla and rainbow trout Oncorhynchus mykiss were challenged by intramuscular injection of zoospores of Aphanomyces invadans, the oomycete associated with epizootic ulcerative syndrome (EUS). The tropical three-spot gourami Trichogaster trichopterus is known to be highly susceptible and was used as a positive control. European catfish were highly susceptible and rainbow trout had moderate to low susceptibility, whereas eels appeared largely unaffected. Inflammatory host response in European catfish deviated from the effects seen in most other susceptible fish species and was characterised by a more loosely arranged accumulation of macrophages, small numbers of lymphocytes and multinucleated giant cells without occurrence of EUS-characteristic mycotic granulomas. Semi-nested and single round PCR assays were developed for this study to detect A. invadans DNA in clinical samples of experimentally infected fish. The detection limit of the assays equals 1 genomic unit. Specificity was examined by testing the DNA of various oomycetes, other relevant pathogens and commensals as well as host DNA. The single round assay used was fully specific, whereas cross-reaction with the closely related Aphanomyces frigidophilus was observed using the semi-nested assay. Analysis of samples by PCR allowed detection prior to detectable histopathological lesions. Two other published PCR protocols were compared to the PCR protocols presented here.

  5. Direct calorimetry of free-moving eels with manipulated thyroid status

    Science.gov (United States)

    van Ginneken, Vincent; Ballieux, Bart; Antonissen, Erik; van der Linden, Rob; Gluvers, Ab; van den Thillart, Guido

    2007-02-01

    In birds and mammals, the thyroid gland secretes the iodothyronine hormones of which tetraiodothyronine (T4) is less active than triiodothyronine (T3). The action of T3 and T4 is calorigenic and is involved in the control of metabolic rate. Across all vertebrates, thyroid hormones also play a major role in differentiation, development and growth. Although the fish thyroidal system has been researched extensively, its role in thermogenesis is unclear. In this study, we measured overall heat production to an accuracy of 0.1 mW by direct calorimetry in a free-moving European eel ( Anguilla anguilla L.) with different thyroid status. Hyperthyroidism was induced by injection of T3 and T4, and hypothyroidism was induced with phenylthiourea. The results show for the first time at the organismal level, using direct calorimetry, that neither overall heat production nor overall oxygen consumption in eels is affected by hyperthyroidism. Therefore, we conclude that the thermogenic metabolism-stimulating effect of thyroid hormones (TH) is not present with a cold-blooded fish species like the European eel. This supports the concept that TH does not stimulate thermogenesis in poikilothermic species.

  6. Fish health and fish quality

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian

    Aquaculture is an expanding worldwide industry producing an increasing amount of fish every year. The quality of the fish meat is dependent upon many biological and non-biological factors. Infectious diseases are known to cause bleedings and damage of the muscle tissue that may lead to scarring...... are poorly described in fish. The present work in this thesis focused on: 1) examination of potential changes in the quality regarding texture of the muscle tissue in rainbow trout (Oncorhynchus mykiss) after previous infection with the bacterial pathogens Yersinia ruckeri and Vibrio anguillarum; 2...... of these studies showed that previous infections by Yersinia ruckeri and Vibrio anguillarum gave rise to subsequent changes regarding textural quality parameters in fresh fish meat, while no differences were seen for cold-smoked meat from the same fish. The texture in previous infected fish was less flaky and less...

  7. Fish parasites

    DEFF Research Database (Denmark)

    This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

  8. One Fish, Two Fish, Redfish, You Fish!

    Science.gov (United States)

    White, Katherine; Timmons, Maryellen; Medders, Paul

    2011-01-01

    The recreational fishing activity presented in this article provides a hands-on, problem-based experience for students; it unites biology, math, economics, environmental policy, and population dynamics concepts. In addition, the activity allows students to shape environmental policy in a realistic setting and evaluate their peers' work. By…

  9. Fighting fish

    Science.gov (United States)

    Duchi, E.; Guerrini, V.; Rinaldi, S.; Schaeffer, G.

    2017-01-01

    We introduce new combinatorial structures, called fighting fish, that generalize directed convex polyominoes by allowing them to branch out of the plane into independent substructures. On the one hand the combinatorial structure of fighting fish appears to be particularly rich: we show that their generating function with respect to the perimeter and number of tails is algebraic, and we conjecture a mysterious multivariate equidistribution property with the left ternary trees introduced by Del Lungo et al On the other hand, fighting fish provide a simple and natural model of random branching surfaces which displays original features: in particular, we show that the average area of a uniform random fighting fish with perimeter 2n is of order n 5/4: to the best of our knowledge this behaviour is non-standard and suggests that we have identified a new universality class of random structures. Dedicated to Tony Guttmann on the occasion of his 70th birthday.

  10. Maternally transferred dioxin-like compounds can affect the reproductive success of European eel.

    Science.gov (United States)

    Foekema, Edwin M; Kotterman, Michiel; de Vries, Pepijn; Murk, Albertinka J

    2016-01-01

    Reported concentrations of dioxin-like compounds accumulated in the European eel (Anguilla anguilla) were used to perform a risk assessment for eel larval survival, taking into account a modeled amplification of tissue concentrations with a factor of 1.33 during spawning migration. The calculated concentrations of dioxin-like compounds finally deposited in the eggs were compared with the internal effect concentrations for survival of early life stages of the European eel; these concentrations, by lack of experimental data, were estimated from a sensitivity distribution based on literature data by assuming that eel larvae are among the 10% most sensitive teleost fish species. Given concentrations of dioxin-like contaminants and assuming a relatively high sensitivity, it can be expected that larvae from eggs produced by eel from highly contaminated locations in Europe will experience increased mortality as a result of maternally transferred dioxin-like contaminants. As historical persistent organic pollutant concentrations in eel tissue were higher, this impact must have been stronger in the past. Potential effects of other compounds or effects on the migration, condition, and fertility of the parental animals were not taken into account. It is important to further study the overall impact of contaminants on the reproductive success of the European eel as this may have been underestimated until now.

  11. The acanthocephalan Paratenuisentis ambiguus as a sensitive indicator of the precious metals Pt and Rh from automobile catalytic converters

    Energy Technology Data Exchange (ETDEWEB)

    Sures, B.; Zimmermann, S.; Sonntag, C.; Stueben, D.; Taraschewski, H

    2003-04-01

    The eel parasite, Paratenuisentis ambiguus, takes up and accumulates catalytic metals. - Recent studies revealed that intestinal acanthocephalans of fish can accumulate heavy metals to concentrations orders of magnitude higher than those in the host tissues or the aquatic environment. This significant heavy metal accumulation by acanthocephalans, even surpassing that of established free living accumulation bioindicators, encouraged us to study the bioavailability of the platinum-group-metals (PGM) Pt and Rh for parasites. These precious metals are used in catalytic converters of cars for exhaust gas purification in Europe since the early 1980s. In addition to the beneficial effect in reducing the emission of CH{sub x}, CO and NO{sub x} of cars there is an increasing emission of these metals. However, it still remains unclear if these elements become accumulated in the biosphere and whether they affect the health of organisms. The present study reveals that in European eels (Anguilla anguilla) naturally infected with the eoacanthocephalan parasite Paratenuisentis ambiguus and experimentally exposed to ground catalytic converter material, the parasites take up and accumulate the catalytic active metals Pt and Rh whereas in the examined host tissues we found no metal uptake. Compared with the PGM concentrations in the water the worms contained 1600 times higher Rh and 50 times higher Pt concentrations. Thus, the parasites can be used as sentinel organisms reflecting even very low levels of precious metals.

  12. Primitive duplicate Hox clusters in the European eel's genome.

    Directory of Open Access Journals (Sweden)

    Christiaan V Henkel

    Full Text Available The enigmatic life cycle and elongated body of the European eel (Anguilla anguilla L., 1758 have long motivated scientific enquiry. Recently, eel research has gained in urgency, as the population has dwindled to the point of critical endangerment. We have assembled a draft genome in order to facilitate advances in all provinces of eel biology. Here, we use the genome to investigate the eel's complement of the Hox developmental transcription factors. We show that unlike any other teleost fish, the eel retains fully populated, duplicate Hox clusters, which originated at the teleost-specific genome duplication. Using mRNA-sequencing and in situ hybridizations, we demonstrate that all copies are expressed in early embryos. Theories of vertebrate evolution predict that the retention of functional, duplicate Hox genes can give rise to additional developmental complexity, which is not immediately apparent in the adult. However, the key morphological innovation elsewhere in the eel's life history coincides with the evolutionary origin of its Hox repertoire.

  13. Panmixia in the European eel: a matter of time…

    Science.gov (United States)

    Dannewitz, Johan; Maes, Gregory E; Johansson, Leif; Wickström, Håkan; Volckaert, Filip A.M; Järvi, Torbjörn

    2005-01-01

    The European eel (Anguilla anguilla L.) has been a prime example of the panmixia paradigm because of its extraordinary adaptation to the North Atlantic gyral system, semelparous spawning in the Sargasso Sea and long trans-oceanic migration. Recently, this view was challenged by the suggestion of a genetic structure characterized by an isolation-by-distance (IBD) pattern. This is only likely if spawning subpopulations are spatially and/or temporally separated, followed by non-random larval dispersal. A limitation of previous genetic work on eels is the lack of replication over time to test for temporal stability of genetic structure. Here, we hypothesize that temporal genetic variation plays a significant role in explaining the spatial structure reported earlier for this species. We tested this by increasing the texture of geographical sampling and by including temporal replicates. Overall genetic differentiation among samples was low, highly significant and comparable with earlier studies (FST=0.0014; p<0.01). On the other hand, and in sharp contrast with current understandings, hierarchical analyses revealed no significant inter-location genetic heterogeneity and hence no IBD. Instead, genetic variation among temporal samples within sites clearly exceeded the geographical component. Our results provide support for the panmixia hypothesis and emphasize the importance of temporal replication when assessing population structure of marine fish species. PMID:16024374

  14. Virginia ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackishwater fish species in Virginia. Vector polygons in this data...

  15. Hawaii ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, marine, estuarine, and native stream fish species in coastal Hawaii. Vector polygons in this data...

  16. Alabama ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and freshwater fish species in Alabama. Vector polygons in this data set represent...

  17. Louisiana ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for freshwater (inland) fish species in coastal Louisiana. Vector polygons represent water-bodies and other...

  18. Natural, social, economical and political influences on fisheries: a review of the transitional area of the Polish waters of the Vistula Lagoon.

    Science.gov (United States)

    Psuty, Iwona

    2010-01-01

    A 60 year (1948-2007) dataset gathered by Polish researchers working on the Vistula Lagoon fish assemblages and fisheries has shown this stressed transitional environment to be always been dominated by a few highly abundant fish species. During this period, the surrounding countries Poland and Russia (Kaliningrad) were transformed from centrally-planned economies with fixed prices to free market systems. The organization of the fishery evolved from one in which the majority of the fishing effort was expended by cooperatives, to one which was characterized by individual economic activity. The fishing gear deployed also evolved from cotton to monofilament, as well as from large sailing vessels with small-sized pair trawls to fyke nets targeting eel (Anguilla anguilla) and pound nets targeting herring (Clupea harengus). Small-sized gillnets targeting perch (Perca fluviatilis) grew in popularity as eel and pikeperch (Sander lucioperca) catches decreased. Cooperation between Polish and Russian fishery managers began in 1952 with the aim of implementing joint agreements to establish protection guidelines. The substantial nutrient loads into the lagoon in 1970 and 1980 put very large pressure on the environment, and contributed to the loss of macrophytes as well as the development of non-commercial fish populations. One of the consequences of these changes was the rapid growth of a black cormorant (Phalacrocorax carbo) breeding colony. These multi-faceted changes are considered to be the factors that have influenced the exploitation of fish assemblages in the Polish part of the Vistula Lagoon. The most evident change in the fish assemblage structure during the study period was the permanent decrease in the basin's top predators--pike (Esox lucius) and pikeperch. Eel stocking was initiated in 1970 following a crucial decline in yield from natural recruitment, and stocking was successful in increasing eel abundance.

  19. Fishing Access Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish & Wildlife Department maintains developed fishing access areas. These sites provide public access to waters in Vermont for shore fishing...

  20. Do bacteria, not fish, produce 'fish kairomone'?

    NARCIS (Netherlands)

    Ringelberg, J.; Van Gool, E.

    1998-01-01

    Fish-associated chemicals enhance phototactic downward swimming in Daphnia. If perch were treated with the antibiotic ampicillin, this enhancement was significantly decreased. Therefore, not fish, but bacteria associated with fish, seem to produce this kairomone. [KEYWORDS: Diel vertical migration;

  1. The Fishing Cat

    Institute of Scientific and Technical Information of China (English)

    孙雅飞; 乐伟国

    2008-01-01

    @@ 一、故事内容 A cat goes fishing every day. He wants to eat fish, but he can't catch any fish. One day, he goes to the river as usual. Suddenly, a fish comes out. He catches the fish and putsthe fish in the basket. He's very happy, but he forgest to put the lid on the basket.

  2. Fish gelatin.

    Science.gov (United States)

    Boran, Gokhan; Regenstein, Joe M

    2010-01-01

    Gelatin is a multifunctional ingredient used in foods, pharmaceuticals, cosmetics, and photographic films as a gelling agent, stabilizer, thickener, emulsifier, and film former. As a thermoreversible hydrocolloid with a narrower gap between its melting and gelling temperatures, both of which are below human body temperature, gelatin provides unique advantages over carbohydrate-based gelling agents. Gelatin is mostly produced from pig skin, and cattle hides and bones. Some alternative raw materials have recently gained attention from both researchers and the industry not just because they overcome religious concerns shared by Jews and Muslims but also because they provide, in some cases, technological advantages over mammalian gelatins. Fish skins from a number of fish species are among the other sources that have been comprehensively studied as sources for gelatin production. Fish skins have a significant potential for the production of high-quality gelatin with different melting and gelling temperatures over a much wider range than mammalian gelatins, yet still have a sufficiently high gel strength and viscosity. Gelatin quality is industrially determined by gel strength, viscosity, melting or gelling temperatures, the water content, and microbiological safety. For gelatin manufacturers, yield from a particular raw material is also important. Recent experimental studies have shown that these quality parameters vary greatly depending on the biochemical characteristics of the raw materials, the manufacturing processes applied, and the experimental settings used for quality control tests. In this review, the gelatin quality achieved from different fish species is reviewed along with the experimental procedures used to determine gelatin quality. In addition, the chemical structure of collagen and gelatin, the collagen-gelatin conversion, the gelation process, and the gelatin market are discussed.

  3. Fish hemoglobins

    Directory of Open Access Journals (Sweden)

    P.C. de Souza

    2007-06-01

    Full Text Available Vertebrate hemoglobin, contained in erythrocytes, is a globular protein with a quaternary structure composed of 4 globin chains (2 alpha and 2 beta and a prosthetic group named heme bound to each one. Having myoglobin as an ancestor, hemoglobin acquired the capacity to respond to chemical stimuli that modulate its function according to tissue requirements for oxygen. Fish are generally submitted to spatial and temporal O2 variations and have developed anatomical, physiological and biochemical strategies to adapt to the changing environmental gas availability. Structurally, most fish hemoglobins are tetrameric; however, those from some species such as lamprey and hagfish dissociate, being monomeric when oxygenated and oligomeric when deoxygenated. Fish blood frequently possesses several hemoglobins; the primary origin of this finding lies in the polymorphism that occurs in the globin loci, an aspect that may occasionally confer advantages to its carriers or even be a harmless evolutionary remnant. On the other hand, the functional properties exhibit different behaviors, ranging from a total absence of responses to allosteric regulation to drastic ones, such as the Root effect.

  4. Fish Tales

    Energy Technology Data Exchange (ETDEWEB)

    McLerran, L.

    2010-07-06

    This talk is about fishing and the friendships that have resulted in its pursuit. It is also about theoretical physics, and the relationship of imagination and fantasy to the establishment of ideas about nature. Fishermen, like theoretical physicists, are well known for their inventive imaginations. Perhaps neither are as clever as sailors, who conceived of the mermaid. If one doubts the power of this fantasy, one should remember the ghosts of the many sailors who drowned pursuing these young nymphs. An extraordinary painting by J. Waterhouse is shown as Fig. 1. The enchantment of a mermaid must reflect an extraordinary excess of imagination on the part of the sailor, perhaps together with an impractical turn of mind. A consummated relationship with a mermaid is after all, by its very nature a fantasy incapable of realization. To a theoretical physicist, she is symbolic of many ideas we develop. There are many truths known to fisherman in which one might also find parallels to the goals of scientists: (1) A fish is the only animal that keeps growing after its death; (2) Nothing makes a fish bigger than almost being caught; (3) ''...of all the liars among mankind, the fisherman is the most trustworthy.'' (William Sherwood Fox, in Silken Lines and Silver Hooks); and (4) Men and fish are alike. They both get into trouble when they open their mouths. These quotes may be interpreted as reflecting skepticism regarding the honesty of fisherman, and probably do not reflect adequate admiration for a creative imagination. Is it fair to criticize a person for believing a falsehood that he or she sincerely believes to be true? The fisherman simultaneously invents the lie, and believes in it himself. The parallel with theoretical physics is perhaps only approximate, although we physicists may invent stories that we come to believe, on some rare occasions our ideas actually correspond to a more or less true descriptions of nature. These minor philosophical

  5. Fish Immunoglobulins

    Science.gov (United States)

    Mashoof, Sara; Criscitiello, Michael F.

    2016-01-01

    The B cell receptor and secreted antibody are at the nexus of humoral adaptive immunity. In this review, we summarize what is known of the immunoglobulin genes of jawed cartilaginous and bony fishes. We focus on what has been learned from genomic or cDNA sequence data, but where appropriate draw upon protein, immunization, affinity and structural studies. Work from major aquatic model organisms and less studied comparative species are both included to define what is the rule for an immunoglobulin isotype or taxonomic group and what exemplifies an exception. PMID:27879632

  6. Fishing activities

    Science.gov (United States)

    Oberle, Ferdinand; Puig, Pere; Martin, Jacobo; Micallef, Aaron; Krastel, Sebastian; Savini, Alessandra

    2018-01-01

    Unlike the major anthropogenic changes that terrestrial and coastal habitats underwent during the last centuries such as deforestation, river engineering, agricultural practices or urbanism, those occurring underwater are veiled from our eyes and have continued nearly unnoticed. Only recent advances in remote sensing and deep marine sampling technologies have revealed the extent and magnitude of the anthropogenic impacts to the seafloor. In particular, bottom trawling, a fishing technique consisting of dragging a net and fishing gear over the seafloor to capture bottom-dwelling living resources has gained attention among the scientific community, policy makers and the general public due to its destructive effects on the seabed. Trawling gear produces acute impacts on biota and the physical substratum of the seafloor by disrupting the sediment column structure, overturning boulders, resuspending sediments and imprinting deep scars on muddy bottoms. Also, the repetitive passage of trawling gear over the same areas creates long-lasting, cumulative impacts that modify the cohesiveness and texture of sediments. It can be asserted nowadays that due to its recurrence, mobility and wide geographical extent, industrial trawling has become a major force driving seafloor change and affecting not only its physical integrity on short spatial scales but also imprinting measurable modifications to the geomorphology of entire continental margins.

  7. Deep Fish.

    Science.gov (United States)

    Ishaq, Omer; Sadanandan, Sajith Kecheril; Wählby, Carolina

    2017-01-01

    Zebrafish ( Danio rerio) is an important vertebrate model organism in biomedical research, especially suitable for morphological screening due to its transparent body during early development. Deep learning has emerged as a dominant paradigm for data analysis and found a number of applications in computer vision and image analysis. Here we demonstrate the potential of a deep learning approach for accurate high-throughput classification of whole-body zebrafish deformations in multifish microwell plates. Deep learning uses the raw image data as an input, without the need of expert knowledge for feature design or optimization of the segmentation parameters. We trained the deep learning classifier on as few as 84 images (before data augmentation) and achieved a classification accuracy of 92.8% on an unseen test data set that is comparable to the previous state of the art (95%) based on user-specified segmentation and deformation metrics. Ablation studies by digitally removing whole fish or parts of the fish from the images revealed that the classifier learned discriminative features from the image foreground, and we observed that the deformations of the head region, rather than the visually apparent bent tail, were more important for good classification performance.

  8. Fishing amplifies forage fish population collapses.

    Science.gov (United States)

    Essington, Timothy E; Moriarty, Pamela E; Froehlich, Halley E; Hodgson, Emma E; Koehn, Laura E; Oken, Kiva L; Siple, Margaret C; Stawitz, Christine C

    2015-05-26

    Forage fish support the largest fisheries in the world but also play key roles in marine food webs by transferring energy from plankton to upper trophic-level predators, such as large fish, seabirds, and marine mammals. Fishing can, thereby, have far reaching consequences on marine food webs unless safeguards are in place to avoid depleting forage fish to dangerously low levels, where dependent predators are most vulnerable. However, disentangling the contributions of fishing vs. natural processes on population dynamics has been difficult because of the sensitivity of these stocks to environmental conditions. Here, we overcome this difficulty by collating population time series for forage fish populations that account for nearly two-thirds of global catch of forage fish to identify the fingerprint of fisheries on their population dynamics. Forage fish population collapses shared a set of common and unique characteristics: high fishing pressure for several years before collapse, a sharp drop in natural population productivity, and a lagged response to reduce fishing pressure. Lagged response to natural productivity declines can sharply amplify the magnitude of naturally occurring population fluctuations. Finally, we show that the magnitude and frequency of collapses are greater than expected from natural productivity characteristics and therefore, likely attributed to fishing. The durations of collapses, however, were not different from those expected based on natural productivity shifts. A risk-based management scheme that reduces fishing when populations become scarce would protect forage fish and their predators from collapse with little effect on long-term average catches.

  9. Sport Fishing Regulations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The regulations for sport fishing on St. Vincent National Wildlife Refuge are outlined in this document. Fishing is only permitted from sunrise to sunset, and only...

  10. Fish Springs pond snail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Communication scenario between the branch of Listing and Recovery, Fish and Wildlife Enhancement, and Fish Springs National Wildlife Refuge (NWR), in regards to the...

  11. Fish tapeworm infection

    Science.gov (United States)

    Fish tapeworm infection is an intestinal infection with the tapeworm parasite found in fish. ... The fish tapeworm ( Diphyllobothrium latum ) is the largest parasite that infects humans. Humans become infected when they eat raw ...

  12. Got a Sick Fish?

    Science.gov (United States)

    ... Welfare Veterinary Careers Public Health Got a sick fish? Fish with disease can show a variety of signs. If you notice your pet fish having any unusual disease signs, contact your veterinarian ...

  13. 日本鳗鲡雌鳗卵巢发育期间肌肉脂肪酸的组成及消耗%COMPOSITION AND METABOLIZING OF LIPIDS AND FATTY ACIDS IN MUSCLE OF FEMALE ANGUILLA JAPONICA DURING THE PERIOD OF ARTIFICIAL INDUCING OVARIAN MATURATION

    Institute of Scientific and Technical Information of China (English)

    柳凌; 李荣; 张洁明; 郭峰; 张涛

    2009-01-01

    研究采用3种不同的处理方式(I&GD、I&nGD和A&nGD)对雌鳗处理后,进行了生物学相关参数、肌肉脂肪酸组成和含量变化测定分析.研究结果表明,日本鳗鲡在性腺发育期间,体重一直呈一个下降的趋势,直到产卵前,才显著高于野生海鳗.该现象被称为水合反应.实验结束时,3个实验组的脂肪总量均有不同程度的下降,其中,I&GD组下降最多,占总脂肪的66.55%;其次是A&nGD组,占总脂肪的43.76%;下降最少的是I&nGD组,占总脂肪的34.68%.研究对日本鳗鲡的肌肉共测出了17种脂肪酸,SFA 7种、MUFA 2种、PUFA 8种.其中,MUFA虽然只有2种,但在脂肪酸总量中占的百分比却较高达38.02%,而且它们的消耗与性腺发育和基础代谢有关,与雌鳗的游泳耗能无关.在8种PUFA中,AA的变化很特殊.实验期间,它在日本鳗鲡肌肉内是一个积累和消耗的动态过程.而且,积累程度与雌鳗的游动有关,游动越多,积累越多.EPA虽然能被检出,但量很低,而且各组间的变化无明显规律.DHA在日本鳗鲡肌肉中的含量达到123.91 mg/g干肌肉,占总脂肪的32.52%.卵巢发育所消耗的量也很多,I&GD组在卵巢发育结束后,下降到10.59 mg/g十肌肉.相关性分析发现.虽然总脂肪酸、PUFA、DHA和EPA与GSI间均存在一定程度的负相关性,但关系最密切的是DHA,其r=-0.952(P<0.01,n=5),关系最小的是EPA,其r=-0.882(P<0.05,n=5).因此分析认为DHA是日本鳗鲡性腺发育所需的最主要的一种脂肪酸.对能量分布进行综合分析后认为,日本鳗鲡在人工诱导性腺发育期间,基础代谢所需的脂肪量(L_(BM))占总脂肪量的34.68%,性腺发育所需脂肪量(L_(GD))占总脂肪量的32.49%,运动耗能所需脂肪量(L_M)占总脂肪量的9.79%.因此认为,日本鳗鲡在不摄食的情况下,肌肉中的脂肪不仅能提供性腺发育所需的营养物质,而且还能满足洄游2000海里到达产卵场所需的能量.%This experiment adopted three methods (I&GD,I&nGD and A&nGD) to treat the females of Japanese eel. After being treated, the biological data of female, which related with their gonadal development, were investigated and the changes of fatty acids in their muscle were measured by gas liquid chromatography. The purpose of this study is try to discuss the lipid consumptions for gonadal development, basal metabolization and migration fuel during spawning migration, as well as the relationship between gonadal development and fatty acids consumption in the period of artificial inducing gonadal maturation, in order to provide referenced foundation for future studies on artificial propagation in Japanese eel. The results indicated that the body weight of females came through a course of gradual downward trend before the 10 injection and rapid rise at the beginning of spawning, which was called hydration, as well as the lipids of muscle tissue were necessary not only for gonadal development, but also for basal metabolization and migration energies in Japanese eels during the spawning migration. In this study, 17 fatty acids were detected in muscle tissues of females, including 7 SFA, 2 MUFA and 8 PUFA. Among them, there were only two kinds of MUFA, but their total levels were higher and reached at 38.02 percent of total lipids. Their consumptions were related with gonadal development and basal metabolization, unrelated to the energy for swimming. Among 8 PUFA, the changes of AA in three treated groups were very special. It was a dynamic course of accumulation and consumption in muscle tissue of Japanese eel during the period of experiment and the accumulation was related with the swimming of females. The more the females swam, the more AA was accumulated in muscle tissues. DHA levels of muscle tissues in Japanese eels were the highest, its change was remarkably different between treated groups and its level in control reached up to (123.91+7.29) mg/g DMW, accounting for 32.52 percent of total lipids. However, its level in I&GD group dropped at (10.59+0.85) mg/g DMW at the end of experiment. Relativity analyses indicated that the relativities between GSI and the levels of total lipids, PUFA, DHA and EPA were all showed in some extent negative relativities, but the closest factor was DHA, r = -0.952(P<0.01 ,n =5) , the most distant one was EPA, r =-0.882 (P<0.05,n=5). Therefore, it was indicated that DHA was the most important fatty acid during the period of gonadal development in Japanese eel. Analyzing for energy distribution considered that the lipid consumption for basal metabolization (L_(BM)) accounted for 34.68% of total lipids, gonadal development (L_(GD)) accounted for 32.94% and swimming energy (L_(SE)) accounted for 9.79%. After finished spawning, the muscle of females was also reserved 23.04% of total lipids. Therefore, it can be undoubted that Japanese eels not only can provide enough energy to finish the spawning migration so far as over 2000 sea miles but also make the gonadal normal development without intake any food.

  14. A STUDY ON JAPANESE EEL ANGUILLA JAPONICA LOW-CARBON AQUACULTURE TECHNIQUE OF BIOFILM IN-SITU BIOREMEDIATION IN EARTHERN POND%日本鳗鲡(Anguillajaponica)土池生物膜原位修复低碳养殖技术的研究

    Institute of Scientific and Technical Information of China (English)

    江兴龙

    2012-01-01

    采用水体中设置生物膜净水栅对比实验的方法,在12口土池开展生物膜原位修复技术对土池淡水养殖日本鳗鲡的节水减排、养殖效益及机理的研究。结果表明,在172d的养殖期间,处理组比对照组节水减排78%(P〈0.01);处理组的氨氮、NO2-N、CODM。溶解性正磷酸盐和浊度分别低于对照组31.7%、49.7%、29.6%、24.2%和26.2%(P〈0.01);藻类密度的变化幅度及蓝藻相对密度分别低于对照组58.8%、52.6%(P〈0.01);净产量、起捕尾重和生长速度分别高出对照组38%、22.7%和27.1%(P〈0.011;饲料系数低于对照组14.2%(P〈0.01);处理组每公顷池塘增加养殖利润约77.25万元。池塘生物膜原位修复低碳养殖技术具有成本低、节水减排、增产增收、操作简便-9易推广等优点,具有广阔的应用前景。%To study the effect of saving water and reducing pollution, culture benefit and mechanism of the technique of biofilm in-situ bioremediation of earthern pond ecosystem for eel intensive culture, the trial was implemented, which included the treatment with biofilm purifying water bar, set in earthern ponds for biofilm developed, and the control without the bar, and used 12 freshwater earthern ponds with Japanese eel (Anguillajaponica) intensively cultivating. The results showed, during the 172 days eel cultivation trial, the treatment saved 78% water exchanged than the control significantly (P〈0.01); the concentrations of TAN, NO2-N, CODMn, soluble reactive phosphate and turbidity in the treatment were sig- nificantly decreased at 31.7%, 49.7%, 29.6%, 24.2% and 26.2% than the control respectively (P〈0.01); the variety range of algae density and blue algae relative density in the treatment were significantly decreased at 58.8% and 52.6% than the control respectively (P〈0.01); the treatment increased net yield, eel harvest size and growth rate at 38%, 22.7% and 27.1% respectively (P〈0.01), and decreased feed conversion rate at 14.2% (P〈0.01) than the control; the treatment increased profit about 772.5 thousand yuan per hectare than the control. In conclusion, pond low-carbon aquaculture technique of biofilm in-situ bioremediation had advantages, such as low cost, saving water and reducing pollution, increasing yield and profit, convenient operation and easy for extension. Therefore, the technique would have a great extension prospect.

  15. Random amplified polymorphic DNA analysis of eel genome

    Institute of Scientific and Technical Information of China (English)

    QIUJIAJING; YIPINGLI

    1999-01-01

    Eel family is a huge one, in which many kinds of eels especially some migratory eels, bear strong resemblance to each other, and are therefore difficult to be identified. In this study 29 random primers were used to make RAPD analysis for Japaneses eel (Anguilla japonica), European eel (Anguilla anguilla) and Pike eel (Muraenesox cinereus).And totally 299 fragments were counted.Shared or specific fragments were counted and genetic similarity or genetic distance were calculated.The genetic similarity between Japanese eel and Pike eel is 0.68 and the genetic distance between them is 0.32;those between European eel and Pike eel are 0.72 and 0.28 respectively,and between Japanese eel and European eel are 0.74 and 0.25 respectively.The method has been shown to be suitable to molecular identification of eels.It provides an alternative approach to determine the relationship between species.

  16. Assessing patterns of hybridization between North Atlantic eels using diagnostic single-nucleotide polymorphisms

    DEFF Research Database (Denmark)

    Pujolar, José Martin; Jacobsen, M.W.; Als, Thomas Damm

    2014-01-01

    The two North Atlantic eel species, the European eel (Anguilla anguilla) and the American eel (Anguilla rostrata), spawn in partial sympatry in the Sargasso Sea, providing ample opportunity to interbreed. In this study, we used a RAD (Restriction site Associated DNA) sequencing approach to identify...... eel) collected in the Sargasso Sea. Our SNP survey showed that the majority of Icelandic eels are pure European eels but there is also an important contribution of individuals of admixed ancestry (10.7%). Although most of the hybrids were identified as F1 hybrids from European eel female × American......, no hybrids were observed in the Faroe Islands, the closest bodies of land to Iceland. It is possible that hybrids show an intermediate migratory behaviour between the two parental species that ultimately brings hybrid larvae to the shores of Iceland, situated roughly halfway between the Sargasso Sea...

  17. Fish mycobacteriosis (Tuberculosis)

    Science.gov (United States)

    Parisot, T.J.; Wood, J.W.

    1959-01-01

    The etiologic agent for the bacterial disease, "fish tuberculosis" (more correctly "mycobacteriosis"), was first observed in carp in 189& from a pond in France. Subsequently similar agents have been isolated from or observed in fish in fresh water, salt water, and brackish water, in fish in aquaria, hatcheries, and natural habitat~ (wild populations of fish). The disease has been recognized as an important infection among hatchery reared salmonid fishes on the West Coast of the United States, and in aquarium fishes such as the neon tetra, the Siamese fighting fish, and in salt water fish held in zoological displays.

  18. Mercury bioaccumulation along food webs in temperate aquatic ecosystems colonized by aquatic macrophytes in south western France.

    Science.gov (United States)

    Gentès, Sophie; Maury-Brachet, Régine; Guyoneaud, Rémy; Monperrus, Mathilde; André, Jean-Marc; Davail, Stéphane; Legeay, Alexia

    2013-05-01

    Mercury (Hg) is considered as an important pollutant for aquatic systems as its organic form, methylmercury (MeHg), is easily bioaccumulated and bioamplified along food webs. In various ecosystems, aquatic periphyton associated with macrophyte was identified as an important place for Hg storage and methylation by microorganisms. Our study concerns temperate aquatic ecosystems (South Western France) colonized by invasive macrophytes and characterized by high mercury methylation potentials. This work establishes original data concerning Hg bioaccumulation in organisms (plants, crustaceans, molluscs and fish) from five contrasting ecosystems. For low trophic level species, total Hg (THg) concentrations were low (from 27±2ngTHgg(-1)dw in asiatic clam Corbicula fluminea to 418±114ngTHgg(-1)dw in crayfish Procambarus clarkii). THg concentrations in some carnivorous fish (high trophic level) were close to or exceeded the International Marketing Level (IML) with values ranging from 1049±220ngTHgg(-1)dw in pike perch muscle (Sander lucioperca) to 3910±1307ngTHgg(-1)dw in eel muscle (Anguilla Anguilla). Trophic levels for the individuals were also evaluated through stable isotope analysis, and linked to Hg concentrations of organisms. A significant Hg biomagnification (r(2)= 0.9) was observed in the Aureilhan lake, despite the absence of top predator fish. For this site, Ludwigia sp. periphyton, as an entry point of Hg into food webs, is a serious hypothesis which remains to be confirmed. This study provides a first investigation of Hg transfer in the ecosystems of south western France and allows the assessment of the risk associated with the presence of Hg in aquatic food webs.

  19. No Fishing Now,More Fish Later

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Fishing ban for ecological purposes starts on the Pearl River Since April1,a two-month ban on fishing has been imposed on the Pearl River valley in south China.It is the first fishing ban in this area with the purpose of preserving biodiversity in China’s third longest

  20. Microbiological spoilage of fish and fish products

    DEFF Research Database (Denmark)

    Gram, Lone; Huss, Hans Henrik

    1996-01-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative...

  1. Plastic fish

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness.   Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...

  2. Hypotonicity induced K+ and anion conductive pathways activation in eel intestinal epithelium

    DEFF Research Database (Denmark)

    Lionetto, M G; Giordano, M E; De Nuccio, F

    2005-01-01

    , the activation of 'emergency' systems of rapid cell volume regulation is fundamental in their physiology. The aim of the present work was to study the physiological response to hypotonic stress in a salt-transporting epithelium, the intestine of the euryhaline teleost Anguilla anguilla. Eel intestinal epithelium......(te)) and the short circuit current (I(sc)). This electrophysiological response correlated with a regulatory volume decrease (RVD) response, recorded by morphometrical measurement of the epithelium height. Changes in the transepithelial resistance were also observed following the hypotonicity exposure...

  3. Salida de campo a La Tour du Valat y La Capeliére (La Camarga, Francia) el 21 de mayo de 1954

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a La Tour du Valat y La Capeliére (La Camarga, Francia) el 21 de mayo de 1954, de la que se anotaron observaciones sobre ranas, los siguientes peces: Anguilla anguilla (Anguila), "Carp. sol", Cyprinus carpio (Carpa) y Gambusia holbrooki (Gambusia), el reptil Natrix natrix (Culebra de collar, llamada Tropidonotus natrix por el autor), los siguientes mamíferos: Mus spicilegus (Ratón), Mustela nivalis (Comadreja) y Rattus norvegicus (Rata parda, llamada E.norvegicus por el autor)...

  4. Loss of European silver eel passing a hydropower station

    DEFF Research Database (Denmark)

    Pedersen, Michael Ingemann; Jepsen, Niels; Aarestrup, Kim

    2012-01-01

    The aim of this study was to assess escapement success of silver eels, Anguilla anguilla (L.), in a lowland river while passing a reservoir and a hydropower station. It was hypothesized that passage success would be lowest at the hydropower station and that survival and migration speed would...... that within the study period, only 23% of the tagged eels reached the tidal limit, mainly due to difficulties in passing the hydropower dam. With such high loss-rates, the escapement goals set in the management plan cannot be achieved...

  5. Oceanic migration behaviour of tropical Pacific eels from Vanuatu

    DEFF Research Database (Denmark)

    Schabetsberger, R; Økland, F; Aarestrup, K

    2013-01-01

    Information on oceanic migrations and spawning areas of tropical Pacific freshwater eels (genus Anguilla) is very limited. Lake Letas and its single outflowing river, Mbe Solomul on Gaua Island, Vanuatu, were surveyed for large migrating individuals. Twenty-four Anguilla marmorata (87 to 142 cm......), 39 A. megastoma (50 to 131 cm), and 3 A. obscura (119 to 126 cm) were caught. Seven individuals were tagged with pop-up satellite transmitters and released offshore. One A. marmorata migrated 843 km towards the South Equatorial Current. The tag surfaced only 330 km from the point where the smallest...

  6. [An investigation of parasites of tench (Tinca tinca L., 1758) in Beyşehir Lake].

    Science.gov (United States)

    Ozan, Selda Tekin; Kir, Ismail; Ayvaz, Yusuf; Barlas, Murat

    2006-01-01

    The aim of this study that was carried out from March 15, 2003 to February15, 2005 was to determine the parasites of tench (Tinca tinca L., 1758) inhabiting the Beyşehir Lake. During the study, a total of 334 tenches (T. tinca ) were caught in different regions of Beyşehir Lake monthly and investigated parasitologically. Endoparasites in tenches were found to be plerocercoids of Ligula intestinalis, Caryophyllaeus laticeps, Bothriocephalus acheilognathi and Proteocephalus torulosus from Cestoda, Asymphylodora tincae from Digenea and Acanthocephalus anguillae from Acanthocephala. Of these parasites, Acanthocephalus anguillae has been recorded for the first time in the tenchs of Turkey.

  7. Three Kinds of Fish

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2012-01-01

    There are three kinds of fish. Fish you were given, fish you bought and fish you lease. This might sound a bit odd, but it is nevertheless the basis for the activities of Danish commercial fishers since the introduction of transferable fishing concessions (TFCs) in 2007. In the current 2012 reform...... of market based systems are wild speculation, concentration and monopolization of fishing access and subsequent leasing with fishing communities and new entrants very likely being worse off (see for example the chapter “From fishing rights to financial derivatives” is this volume or Olson 2011; Sumaila 2010...... will examine five Danish fishing operations and discuss how they have reacted in different ways to the newly introduced system of transferable fishing concessions. By introducing TFCs as a solution to fleet overcapacity, the EU Commission will also be introducing a system where buying, selling and leasing...

  8. ESTIMATING THE STOCK OF GLASS EELS IN AN ESTUARY BY MARK-RECAPTURE EXPERIMENTS USING VITAL DYES

    Directory of Open Access Journals (Sweden)

    BRIAND C.

    2005-10-01

    Full Text Available Glass eels (Anguilla anguilla arriving after the fishing season in the Vilaine estuary (France were caught by boat and at a trapping ladder located at a blocking dam upstream in the estuary. They were marked with Bismarck brown, rhodamine B or neutral red, and released into the estuary. The effect of marking on behaviour, mortality and recapture differed according to the dye and concentration used. The glass eels also differed in response to marking according to their origin. Estuarine glass eels were clearly desynchronized in their selective tidal stream transport and left the release area after a few tidal cycles. Trapped glass eels were less sensitive to marking. They remained in the release area and were recaptured in larger number both in the trapping ladder and in the estuary. These results supported a model of two behavioral fractions in the estuary: flow-carried migrants and active glass eels with stronger rheotactic behaviour. The proportion of active glass eels in the estuary shifted from none for the two weeks after the fishery closure, to 10% value of the total stock. At the trapping ladder, the migration ended in June each year, while a large stock was still present in the estuary. These observations favour the interpretation of a short duration of the active phase at this site followed by the transition towards a more benthic behavior. The daily efficiency of the trapping ladder was calculated as 4% of the active stock from both stock estimations and average recapture rate. This value was consistent with the low annual efficiency of the trapping ladder, calculated as 30% of the estuarine stock of glass eels that arrived after the fishing season.

  9. Umatilla - Rough Fish Eradication

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In order to enhance environmental conditions in the McCormack Slough on Umatilla NWR, the population of rough fish, including common carp (Cyprinus carpio) and...

  10. Textbook of fish health

    National Research Council Canada - National Science Library

    Post, George

    1987-01-01

    Written to fill the great need for a fish disease textbook for college students, this new edition contains the latest information and important discoveries related to those fish diseases that affect man economically...

  11. Scorpion fish sting

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002849.htm Scorpion fish sting To use the sharing features on this page, please enable JavaScript. Scorpion fish are members of the family Scorpaenidae, which ...

  12. Pittsburgh Fish Fry Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Lenten Fish Fry records for the Greater Pittsburgh region. Data is collected before and during the Lenten fish fry season each year by Code for Pittsburgh. Data is...

  13. 49 CFR 173.218 - Fish meal or fish scrap.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Fish meal or fish scrap. 173.218 Section 173.218... Fish meal or fish scrap. (a) Except as provided in Column (7) of the HMT in § 172.101 of this subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized...

  14. Medusivorous fishes, a review

    NARCIS (Netherlands)

    Ates, R.M.L.

    1988-01-01

    A preliminary review is presented of fish species having consumed pelagic Cnidaria (Scyphozoa and Hydrozoa) as well as Ctenophora. Quantitative data are scarce. Knowledge of morphological and physiological adaptations of fishes foraging on gelatinous plankton is almost non-existent. Many fish specie

  15. Medusivorous fishes, a review

    OpenAIRE

    Ates, R.M.L.

    1988-01-01

    A preliminary review is presented of fish species having consumed pelagic Cnidaria (Scyphozoa and Hydrozoa) as well as Ctenophora. Quantitative data are scarce. Knowledge of morphological and physiological adaptations of fishes foraging on gelatinous plankton is almost non-existent. Many fish species consume medusae and some reasons to suspect that there are even more that do so, are discussed.

  16. Medusivorous fishes, a review

    NARCIS (Netherlands)

    Ates, R.M.L.

    1988-01-01

    A preliminary review is presented of fish species having consumed pelagic Cnidaria (Scyphozoa and Hydrozoa) as well as Ctenophora. Quantitative data are scarce. Knowledge of morphological and physiological adaptations of fishes foraging on gelatinous plankton is almost non-existent. Many fish

  17. Fish allergy: in review.

    Science.gov (United States)

    Sharp, Michael F; Lopata, Andreas L

    2014-06-01

    Globally, the rising consumption of fish and its derivatives, due to its nutritional value and divergence of international cuisines, has led to an increase in reports of adverse reactions to fish. Reactions to fish are not only mediated by the immune system causing allergies, but are often caused by various toxins and parasites including ciguatera and Anisakis. Allergic reactions to fish can be serious and life threatening and children usually do not outgrow this type of food allergy. The route of exposure is not only restricted to ingestion but include manual handling and inhalation of cooking vapors in the domestic and occupational environment. Prevalence rates of self-reported fish allergy range from 0.2 to 2.29 % in the general population, but can reach up to 8 % among fish processing workers. Fish allergy seems to vary with geographical eating habits, type of fish processing, and fish species exposure. The major fish allergen characterized is parvalbumin in addition to several less well-known allergens. This contemporary review discusses interesting and new findings in the area of fish allergy including demographics, novel allergens identified, immunological mechanisms of sensitization, and innovative approaches in diagnosing and managing this life-long disease.

  18. Do Fish Resist?

    Directory of Open Access Journals (Sweden)

    Dinesh Joseph Wadiwel

    2016-03-01

    Full Text Available There have been a number of scientific studies on the question of whether fish feel pain. Some have suggested that some fish indeed do feel pain and that this has significant welfare implications (2003. Others have argued that fish do not have the brain development necessary to feel pain. In terms of number of animals killed, the slaughter of sea animals for human consumption significantly exceeds that of any land animals that we use for food, and sea animal slaughter practices frequently lack any basic welfare protections. If fish can be shown to feel pain—or more importantly, if humans can agree that fish feel pain—then this would place a significant question mark over many contemporary fishing practices.  This article substitutes the question 'Do Fish Feel Pain?' with an alternative: 'Do Fish Resist?' It explores the conceptual problems of understanding fish resistance, and the politics of epistemology that surrounds and seeks to develop a conceptual framework for understanding fish resistance to human capture by exploring the development of fishing technologies - the hook, the net and contemporary aquaculture.

  19. Fish under exercise.

    Science.gov (United States)

    Palstra, Arjan P; Planas, Josep V

    2011-06-01

    Improved knowledge on the swimming physiology of fish and its application to fisheries science and aquaculture (i.e., farming a fitter fish) is currently needed in the face of global environmental changes, high fishing pressures, increased aquaculture production as well as increased concern on fish well-being. Here, we review existing data on teleost fish that indicate that sustained exercise at optimal speeds enhances muscle growth and has consequences for flesh quality. Potential added benefits of sustained exercise may be delay of ovarian development and stimulation of immune status. Exercise could represent a natural, noninvasive, and economical approach to improve growth, flesh quality as well as welfare of aquacultured fish: a FitFish for a healthy consumer. All these issues are important for setting directions for policy decisions and future studies in this area. For this purpose, the FitFish workshop on the Swimming Physiology of Fish ( http://www.ub.edu/fitfish2010 ) was organized to bring together a multidisciplinary group of scientists using exercise models, industrial partners, and policy makers. Sixteen international experts from Europe, North America, and Japan were invited to present their work and view on migration of fishes in their natural environment, beneficial effects of exercise, and applications for sustainable aquaculture. Eighty-eight participants from 19 different countries contributed through a poster session and round table discussion. Eight papers from invited speakers at the workshop have been contributed to this special issue on The Swimming Physiology of Fish.

  20. Zoonoses associated with fish.

    Science.gov (United States)

    Boylan, Shane

    2011-09-01

    The taxonomic group that composes the fishes is the most diverse group of vertebrates worldwide. The challenges of unique physiologies, a foreign environment, and many unknowns attract a passionate group of biologists and veterinarians. Economically, fishes have become vital as food, bait, and companion animals. Fishermen and fish handlers (processing plants) represent the historical human population exposed to fish zoonoses, but growth in aquaculture and aquarium hobbyists have led to an increase in published fish-borne zoonotic cases starting in the late 1950s that bloomed in the 1980s. Human physicians, particularly dermatologists and infectious disease specialists, are now more aware of fish-borne zoonoses, but they can be assisted with diagnosis when informed patients give more detailed histories with fish/water exposure.

  1. A global viability assessment of the European eel.

    Science.gov (United States)

    Bevacqua, Daniele; Melià, Paco; Gatto, Marino; De Leo, Giulio A

    2015-09-01

    The global European eel (Anguilla anguilla) stock is critically endangered according to the IUCN, and the European Commission has urged the development of conservation plans aimed to ensure its viability. However, the complex life cycle of this panmictic species, which reproduces in the open ocean but spends most of its prereproductive life in continental waters (thus embracing a huge geographic range and a variety of habitat types), makes it difficult to assess the long-term effectiveness of conservation measures. The interplay between local and global stressors raises intriguing cross-scale conservation challenges that require a comprehensive modelling approach to be addressed. We developed a full life cycle model of the global European eel stock, encompassing both the oceanic and the continental phases of eel's life, and explicitly allowing for spatial heterogeneity in vital rates, availability of suitable habitat and settlement potential via a metapopulation approach. We calibrated the model against a long-term time series of global European eel catches and used it to hindcast the dynamics of the stock in the past and project it over the 21st century under different management scenarios. Although our analysis relies on a number of inevitable simplifying assumptions and on data that may not embrace the whole range of variation in population dynamics at the small spatiotemporal scale, our hindcast is consistent with the general pattern of decline of the stock over recent decades. The results of our projections suggest that (i) habitat loss played a major role in the European eel decline; (ii) the viability of the global stock is at risk if appropriate protection measures are not implemented; (iii) the recovery of spawner escapement requires that fishing mortality is significantly reduced; and (iv) the recovery of recruitment might not be feasible if reproductive output is not enhanced. © 2015 John Wiley & Sons Ltd.

  2. Application of an immunoperoxidase staining method for detection of 7,8-dihydro-8-oxodeoxyguanosine as a biomarker of chemical-induced oxidative stress in marine organisms

    Energy Technology Data Exchange (ETDEWEB)

    Machella, Nicola; Regoli, Francesco; Cambria, Antonio; Santella, Regina M

    2004-03-30

    7,8-Dihydro-8-oxodeoxyguanosine (8-oxo-dG) is a typical modification of DNA caused by oxygen free radicals and can be an useful biomarker for pollutants inducing oxidative stress. An immunoperoxidase method using monoclonal antibody 1F7 toward 8-oxo-dG was applied to tissues and smeared cells of marine organisms for detection and quantification of oxidative DNA damage in such models. The assay, previously employed on human cells, was assessed for the first time on Mediterranean mussels (Mytilus galloprovincialis) and European eels (Anguilla anguilla), exposed to model pro-oxidant chemicals, namely benzo[a]pyrene (B[a]P) and copper. Quantification of 8-oxo-dG was microscopically carried out and expressed as relative nuclear staining intensity. Higher levels of oxidative DNA damage were detected in the digestive glands of treated mussels compared to controls, while the effect was less pronounced in haemocytes, characterized by more elevated basal levels of 8-oxo-dG. The assay was suitable for detection of 8-oxo-dG also in fish liver sections indicating consistent damage after B[a]P exposure. The main advantage of the immunohistochemical approach is the elimination of DNA extraction which considerably reduces the processing of biological samples. In addition, the assay requires small amounts of frozen tissues or fixed cells for detection of 8-oxo-dG and is potentially able to discriminate variable susceptibility to oxidative stress in different cell types. Although further investigations are required for the improvement and the validation of the assay in field conditions, laboratory exposures provided useful indications on the consistency of the approach and the efficacy of antibody 1F7 in marine organisms for a rapid assessment of pollutant-induced oxidative DNA damage.

  3. Southeast Alaska ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for estuarine, benthic, and pelagic fish in Southeast Alaska. Vector polygons in this data set represent locations of...

  4. Columbia River ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Columbia River. Vector polygons in this...

  5. North Slope, Alaska ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species for the North Slope of Alaska. Vector...

  6. American Samoa ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, pelagic, benthic, and estuarine fish species in American Samoa. Vector polygons in this data set...

  7. Fish elevator and method of elevating fish

    Science.gov (United States)

    Truebe, Jonathan; Drooker, Michael S.

    1984-01-01

    A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

  8. Curriculum Development for Learning To Live Together: The Caribbean Sub-Region. The Final Report of the Sub-Regional Seminar (Havana, Cuba, May 15-18, 2001).

    Science.gov (United States)

    Byron, Isabel, Ed.; Rozemeijer, Saskia, Ed.

    A sub-regional seminar based on the theme, "Curriculum Development for Learning to Live Together" (Havana, Cuba, May 15-18, 2001), brought together 20 member states of the United Nations Educational, Scientific, and Cultural Organization's Caribbean Network of Educational Innovation for Development: Antigua and Barbuda, Anguilla, Aruba,…

  9. 19 CFR 4.94 - Yacht privileges and obligations.

    Science.gov (United States)

    2010-04-01

    ... Sweden Switzerland Turkey United Kingdom and the Dependencies: the Anguilla Islands, the Isle of Man, the... shall set forth the owner's name and address and identify the vessel by flag, rig, name, and such other... period of ____ from ____(Date) the ____(Flag) ____ (Rig) yacht ____(Name) belonging to ________ of...

  10. Decapod crustaceans from the Neogene of the Caribbean: diversity, distribution and prospectus

    NARCIS (Netherlands)

    Collins, J.S.H.; Portell, R.W.; Donovan, S.K.

    2009-01-01

    The Neogene decapod crustaceans are reviewed from Aruba, Bonaire and Curaçao, Anguilla, Barbados, Carriacou, Costa Rica, Cuba, Florida, Hispaniola (Haiti and Dominican Republic), Jamaica, Mexico, Panama, Puerto Rico, St. Kitts, Tintamare Island, Trinidad and Venezuela. The most widely distributed ta

  11. Development of a polymerase chain reaction for the detection of Anguillid herpesvirus DNA in eels based on the herpesvirus DNA polymerase gene

    NARCIS (Netherlands)

    Rijsewijk, F.A.M.; Pritz-Verschuren, S.B.E.; Kerkhoff, S.; Botter, A.; Willemsen, M.; Nieuwstadt, A.; Haenen, O.L.M.

    2005-01-01

    Anguillid herpesvirus (AnHV, also known as Herpesvirus anguillae or HVA) is found in both Japanese and European eels. Based on restriction enzyme analysis a small number of differences were found between AnHV isolated from Japanese eels and from European eels. The total genome size of both is about

  12. Decapod crustaceans from the Neogene of the Caribbean: diversity, distribution and prospectus

    NARCIS (Netherlands)

    Collins, J.S.H.; Portell, R.W.; Donovan, S.K.

    2009-01-01

    The Neogene decapod crustaceans are reviewed from Aruba, Bonaire and Curaçao, Anguilla, Barbados, Carriacou, Costa Rica, Cuba, Florida, Hispaniola (Haiti and Dominican Republic), Jamaica, Mexico, Panama, Puerto Rico, St. Kitts, Tintamare Island, Trinidad and Venezuela. The most widely distributed

  13. 47 CFR 52.5 - Definitions.

    Science.gov (United States)

    2010-10-01

    ... assign of a member described in paragraph (a)(2)(i) of this section. (b) North American Numbering Council (NANC). The “North American Numbering Council” is an advisory committee created under the Federal... telecommunications networks located in American Samoa, Anguilla, Antigua, Bahamas, Barbados, Bermuda, British...

  14. Mosquito Information Management Project (MIMP): Application of a Computerized Genral Purpose Information Management System (Selgem) to Medically Important Arthropods (Diptera: Culicidae).

    Science.gov (United States)

    1983-08-01

    ominican Republic, Haiti, Jamaica, Puerto Rico, and Virgin Islands. 6. Lesser Antilles-includes Anguilla, Antigua , Barbados, Barbuda, Dominica, Grenada...USAF, OEHL/ECQ, Brooks AFB, TX; 8) Nucleo de Medicina Tropical e Nutricao, Universidad de Brazilia, Brazil; 9) USAMRU-Kenya; 10) London School of

  15. Do Fish Sleep?

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Most fish can’t shut their eyes, so it’s easy to think they don’t sleep. But that’s like assuming humans don’t sleep because we can’t shut our ears to drown out sound. In fact, many species of fish take time out during the day or (more often) at night to enter a sleeplike stage. Some of these fish float in place, others lie on the bottom。

  16. Fish and wildlife surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the monitoring of radioactive contaminants in fish and wildlife species that inhabit the Colombia River and Hanford Site. Wildlife have access to areas of the Site containing radioactive contamination, and fish can be exposed to contamination in spring water entering the river along the shoreline. Therefore, samples are collected at various locations annually, generally during the hunting or fishing season, for selected species.

  17. Persistent chlorinated hydrocarbons (PHC) - end products and intermediate products of technical synthesis processes in surface water of the Rhine region. Vol. 5: Site profiles of persistent chlorinated hydrocarbons - source-oriented monitoring in aquatic media; Persistente chlorierte Kohlenwasserstoffe (PCKW) - End- und Zwischenprodukte technischer Synthesen in Gewaessern der Rheinregion. Band 5 der Reihe: Standortprofile persistenter chlorierter Kohlenwasserstoffe - ursachenorientiertes Monitoring in aquatischen Medien

    Energy Technology Data Exchange (ETDEWEB)

    Heinisch, E.; Kettrup, A.; Bergheim, W.; Wenzel, S.

    2003-07-01

    By evaluating the primary data from 20 regional institutions in the period 1984-2002 about persistent chlorinated hydrocarbons (PCHC) in fishes (eels, Anguilla anguilla; breams, Abramis brama; barbs, Barbus barbus and reaches, Rutilus rutilus), sediment and suspended matter it was tried to mark the burdens and substance profiles for sampling sites on the river Rhine and rivers in BW, Hess, RP and NRW. The compounds investigated were the isomere di-, tri- and tetrachlorobenzenes, penta- and hexachlorobenzene, octachlorostyrene (OCS), hexachlorobutadiene (HCBD) as well as the 6 DIN (IUPAC, Ballschmiter) congeners of the PCB, substances which were - as to the REACH - described as PBT, partly as vPvB substances and regarded as ''priority harmful substances'' (PCBz; HCB, HCBD), respectively. The statistically elaborated single data were summarized in distance profiles and time series, aiming at marking local and regional immissions as well as hints to their origin and current importance. The background of these efforts is the lack of specialized publications about technical synthesis or compulsory yield of the compounds concerning kind, amount and period. Especially tetrachlorobenzene (mainly 1,2,4,5-TeCBz) and HCBD could be defined as indicator substances for past and recent technical synthesis of chloroorganic compounds. The higher chlorinated PCB congeners no. 138, 153 and 180 (HPCB) proved very persistent. The sites of chemical industry in the vicinity of the sampling points Rheinfelden, Grenzach, Lampertheimer Altrhein, Biebesheimer Rhein, Muendung Schwarzbach, Bischofsheim and Griesheim (Main), Hitdorf, Duisburg-Homberg und Huels (Lippe) could be made transparent by maxima and special substance patterns. (orig.) [German] Durch Auswertung von Primaerdaten ueber persistente chlorierte Kohlenwasserstoffe (PCKW) in Fischen (Aale, Anguilla anguilla; Brachsen, Abramis brama; Barben, Barbus barbus und Rotaugen, Rutilus rutilus), Sediment und

  18. Combating Illegal Fishing

    Directory of Open Access Journals (Sweden)

    Sorin Stanciu

    2010-10-01

    Full Text Available Illegal, unreported and unregulated (IUU fishing is a worldwide phenomenon. Its extent and its environmental,economic and social consequences are such that it has become a priority issue at international level. IUU fishingcontributes to the depletion of fish stocks and jeopardises protection and recovery measures put in place to ensure theviability of resources. It represents unfair competition for those who exploit fish resources legally. The Commissionhave been involved in the fight against IUU fishing for over a decade and in 2002 the Commission adopted an ActionPlan against IUU fishing inspired by the FAOs International Plan of Action to prevent, deter and eliminate IUUfishing of 2001. However, despite regional and international efforts to stop IUU fishing the phenomenon is still agrowing problem and as a result, the European Community intensified its action towards IUU fishing by launching aconsultation process in 2007. A Proposal to prevent, deter and eliminate IUU fishing was adopted in October 2007and a Regulation to prevent, deter and eliminate illegal, unreported and unregulated (IUU fishing was adopted on 29September 2008, after a unanimous political agreement.

  19. Anglers' fishing problem

    CERN Document Server

    Karpowicz, Anna

    2011-01-01

    The considered model will be formulated as related to "the fishing problem" even if the other applications of it are much more obvious. The angler goes fishing. He uses various techniques and he has at most two fishing rods. He buys a fishing ticket for a fixed time. The fishes are caught with the use of different methods according to the renewal processes. The fishes' value and the inter arrival times are given by the sequences of independent, identically distributed (i.i.d.) random variables with the known distribution functions. It forms the marked renewal--reward process. The angler's measure of satisfaction is given by the difference between the utility function, depending on the value of the fishes caught, and the cost function connected with the time of fishing. In this way, the angler's relative opinion about the methods of fishing is modelled. The angler's aim is to have as much satisfaction as possible and additionally he has to leave the lake before a fixed moment. Therefore his goal is to find two...

  20. Of Fish and Micrornas

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    Fish is an important small vertebrate multidisciplinary model for investigating various aspects of reproduction, development, disease (immunology, toxicology, carcinogenesis), and aging. It is also an important model for comparative and evolutionary studies because it represents the lower...... to the mechanisms of control of gene expression, impacting a broad range of biological processes. Thus far, >25, 000 miRNA sequences have been identified in 193 species, including fish. In fish, the interest on miRNAs started with the analysis of their expression and function during embryonic development. In our...... selection markers to identify disease-resistant fish....

  1. Intelligent Fish Freshness Assessment

    Directory of Open Access Journals (Sweden)

    Hamid Gholam Hosseini

    2008-01-01

    Full Text Available Fish species identification and automated fish freshness assessment play important roles in fishery industry applications. This paper describes a method based on support vector machines (SVMs to improve the performance of fish identification systems. The result is used for the assessment of fish freshness using artificial neural network (ANN. Identification of the fish species involves processing of the images of fish. The most efficient features were extracted and combined with the down-sampled version of the images to create a 1D input vector. Max-Win algorithm applied to the SVM-based classifiers has enhanced the reliability of sorting to 96.46%. The realisation of Cyranose 320 Electronic nose (E-nose, in order to evaluate the fish freshness in real-time, is experimented. Intelligent processing of the sensor patterns involves the use of a dedicated ANN for each species under study. The best estimation of freshness was provided by the most sensitive sensors. Data was collected from four selected species of fishes over a period of ten days. It was concluded that the performance can be increased using individual trained ANN for each specie. The proposed system has been successful in identifying the number of days after catching the fish with an accuracy of up to 91%.

  2. Essential Fish Habitat (EFH) Areas Protected From Fishing

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Designated Essential Fish Habitat (EFH) areas where fishing or the use of fishing gears has been restricted or modified in order to minimize the adverse effects of...

  3. Fish silage as feed ingredient for fish and livestock

    NARCIS (Netherlands)

    Rurangwa, E.; Vuuren, van A.M.; Poelman, M.

    2014-01-01

    The present report analyses through a literature review the potential of fish silage to valorise fish processing by-products into economically relevant protein sources for fish and livestock feed production in East Africa.

  4. Fish Springs NWR mammal, fish, amphibian, and reptile list

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The following is a species list for mammals, fishes, amphibians, and reptiles found on or adjacent to Fish Springs National Wildlife Refuge, as of October, 1996.

  5. Alaskan sport fishing waters

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — As a guide to newcomers and visitors, fishery biologists have compiled a list of some of the well-known fishing waters in Alaska. The list is merely a starting point...

  6. Ammonia toxicity in fish.

    Science.gov (United States)

    Randall, D J; Tsui, T K N

    2002-01-01

    Ammonia is present in the aquatic environment due to agricultural run-off and decomposition of biological waste. Ammonia is toxic to all vertebrates causing convulsions, coma and death, probably because elevated NH4+ displaces K+ and depolarizes neurons, causing activation of NMDA type glutamate receptor, which leads to an influx of excessive Ca2+ and subsequent cell death in the central nervous system. Present ammonia criteria for aquatic systems are based on toxicity tests carried out on, starved, resting, non-stressed fish. This is doubly inappropriate. During exhaustive exercise and stress, fish increase ammonia production and are more sensitive to external ammonia. Present criteria do not protect swimming fish. Fish have strategies to protect them from the ammonia pulse following feeding, and this also protects them from increases in external ammonia, as a result starved fish are more sensitive to external ammonia than fed fish. There are a number of fish species that can tolerate high environmental ammonia. Glutamine formation is an important ammonia detoxification strategy in the brain of fish, especially after feeding. Detoxification of ammonia to urea has also been observed in elasmobranches and some teleosts. Reduction in the rate of proteolysis and the rate of amino acid catabolism, which results in a decrease in ammonia production, may be another strategy to reduce ammonia toxicity. The weather loach volatilizes NH3, and the mudskipper, P. schlosseri, utilizes yet another unique strategy, it actively pumps NH4+ out of the body.

  7. PARASITES OF FISH

    Science.gov (United States)

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  8. Hawaiian Fish Distributors Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is proprietary sales data from one Kona-based fish dealer for about one year back in the late 1980s. Fishing was generally around Kona. This is Dealer Data and...

  9. Virus diseases of fish

    Science.gov (United States)

    Watson, Stanley W.

    1954-01-01

    Viruses are probably the cause of a wide spectrum of fish diseases. Although relatively few virus diseases of fish are known today, some of the diseases of unknown etiology, as well as some diseases presently accepted as due to bacteria, protozoa, fungi or nutritional deficiencies, possibly will be recognized eventually as virus diseases.

  10. Enzymes in Fermented Fish.

    Science.gov (United States)

    Giyatmi; Irianto, H E

    Fermented fish products are very popular particularly in Southeast Asian countries. These products have unique characteristics, especially in terms of aroma, flavor, and texture developing during fermentation process. Proteolytic enzymes have a main role in hydrolyzing protein into simpler compounds. Fermentation process of fish relies both on naturally occurring enzymes (in the muscle or the intestinal tract) as well as bacteria. Fermented fish products processed using the whole fish show a different characteristic compared to those prepared from headed and gutted fish. Endogenous enzymes like trypsin, chymotrypsin, elastase, and aminopeptidase are the most involved in the fermentation process. Muscle tissue enzymes like cathepsins, peptidases, transaminases, amidases, amino acid decarboxylases, glutamic dehydrogenases, and related enzymes may also play a role in fish fermentation. Due to the decreased bacterial number during fermentation, contribution of microbial enzymes to proteolysis may be expected prior to salting of fish. Commercial enzymes are supplemented during processing for specific purposes, such as quality improvement and process acceleration. In the case of fish sauce, efforts to accelerate fermentation process and to improve product quality have been studied by addition of enzymes such as papain, bromelain, trypsin, pepsin, and chymotrypsin. © 2017 Elsevier Inc. All rights reserved.

  11. Folkbiology of Freshwater Fish

    Science.gov (United States)

    Medin, Douglas L.; Ross, Norbert O.; Atran, Scott; Cox, Douglas; Coley, John; Proffitt, Julia B.; Blok, Sergey

    2006-01-01

    Cross-cultural comparisons of categorization often confound cultural factors with expertise. This paper reports four experiments on the conceptual behavior of Native American and majority-culture fish experts. The two groups live in the same general area and engage in essentially the same set of fishing-related behaviors. Nonetheless, cultural…

  12. Biannual Fish Survey, Spring 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The biannual fish survey was initiated in 1989 to monitor population trends of federally endangered fish species at Ash Meadows National Wildlife Refuge. Item 421 of...

  13. Innovation in utilization of fish tanks for fish culture among fish ...

    African Journals Online (AJOL)

    ... of fish tanks for fish culture among fish farmers in Obio/Akpor Local Government, Rivers State, Nigeria. ... Open Access DOWNLOAD FULL TEXT ... Data for this study was obtained through the administration of questionnaire and scheduled ...

  14. Olfactory toxicity in fishes.

    Science.gov (United States)

    Tierney, Keith B; Baldwin, David H; Hara, Toshiaki J; Ross, Peter S; Scholz, Nathaniel L; Kennedy, Christopher J

    2010-01-21

    Olfaction conveys critical environmental information to fishes, enabling activities such as mating, locating food, discriminating kin, avoiding predators and homing. All of these behaviors can be impaired or lost as a result of exposure to toxic contaminants in surface waters. Historically, teleost olfaction studies have focused on behavioral responses to anthropogenic contaminants (e.g., avoidance). More recently, there has been a shift towards understanding the underlying mechanisms and functional significance of contaminant-mediated changes in fish olfaction. This includes a consideration of how contaminants affect the olfactory nervous system and, by extension, the downstream physiological and behavioral processes that together comprise a normal response to naturally occurring stimuli (e.g., reproductive priming or releasing pheromones). Numerous studies spanning several species have shown that ecologically relevant exposures to common pollutants such as metals and pesticides can interfere with fish olfaction and disrupt life history processes that determine individual survival and reproductive success. This represents one of the pathways by which toxic chemicals in aquatic habitats may increasingly contribute to the decline and at-risk status of many commercially and ecologically important fish stocks. Despite our emerging understanding of the threats that pollution poses for chemical communication in aquatic communities, many research challenges remain. These include: (1) the determination of specific mechanisms of toxicity in the fish olfactory sensory epithelium; (2) an understanding of the impacts of complex chemical mixtures; (3) the capacity to assess olfactory toxicity in fish in situ; (4) the impacts of toxins on olfactory-mediated behaviors that are still poorly understood for many fish species; and (5) the connections between sublethal effects on individual fish and the long-term viability of wild populations. This review summarizes and integrates

  15. Why do fish school?

    Institute of Scientific and Technical Information of China (English)

    Matz LARSSON

    2012-01-01

    Synchronized movements (schooling) emit complex and overlapping sound and pressure curves that might confuse the inner ear and lateral line organ (LLO) of a predator.Moreover,prey-fish moving close to each other may blur the electro-sensory perception of predators.The aim of this review is to explore mechanisms associated with synchronous swimming that may have contributed to increased adaptation and as a consequence may have influenced the evolution of schooling.The evolutionary development of the inner ear and the LLO increased the capacity to detect potential prey,possibly leading to an increased potential for cannibalism in the shoal,but also helped small fish to avoid joining larger fish,resulting in size homogeneity and,accordingly,an increased capacity for moving in synchrony.Water-movements and incidental sound produced as by-product of locomotion (ISOL) may provide fish with potentially useful information during swimming,such as neighbour body-size,speed,and location.When many fish move close to one another ISOL will be energetic and complex.Quiet intervals will be few.Fish moving in synchrony will have the capacity to discontinue movements simultaneously,providing relatively quiet intervals to allow the reception of potentially critical environmental signals.Besides,synchronized movements may facilitate auditory grouping of ISOL.Turning preference bias,well-functioning sense organs,good health,and skillful motor performance might be important to achieving an appropriate distance to school neighbors und aid the individual fish in reducing time spent in the comparatively less safe school periphery.Turning preferences in ancestral fish shoals might have helped fish to maintain groups and stay in formarion,reinforcing aforementioned predator confusion mechanisms,which possibly played a role in the lateralization of the vertebrate brain [Current Zoology 58 (1):116-128,2012].

  16. West Lake Fish

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    Sweet & Sour Fish is widely recognized as the best fish recipe found in the city of Hangzhou. The delectable tender sweet & sour dish would please the palate of even the most demanding gourmet. The unique preparation method follows: Method: Place a one kilogram grass carp in clear water for three days to eliminate any offensive odor, and allowing adequate time for defecation. Gut and clean the carp thoroughly. Slice open the belly, Make five equally spaced one centimeter deep incisions on one side of the fish, and another slanting cut through the thick meat on the opposite side. Be certain to ensure the

  17. An updated checklist of poisonous ifshes of Turkish Aegean Sea

    Institute of Scientific and Technical Information of China (English)

    Bahar Bayhan; Murat Kaya

    2015-01-01

    The current status of marine poisonous fish species ranging in the Aegean Sea coastline in Turkey were introduced. Turkey is a peninsula surrounded by seas with different ecological features on three sides. The total length of shoreline is 8 333 km including the islands. The total number of fish species in Turkish seas is 512, of which 449 live in the Aegean Sea followed by the Mediterranean Sea (441 species), the Marmara Sea (257 species) and the Black Sea (154species). On the Aegean Sea coasts, the richest sea regarding fish diversity, the number of poisonous fish species is also high. This mini-review revealed 51 poisonous fish species belonging to 14 families in the Turkish Aegean Sea. On the Aegean Sea coasts poisonous fish species can be categorized into three groups: (i) Fish that contain venomous spines on the tail or on the operculum (ii) Fish that carry poisonous bite and (iii) Fish having poisonous flesh or liver. Poisoning fish that contain venomous spines on the tail or on the operculum mostly are dangerous because of their poisonous thorns whereas the passive poisonous fish species poison when they are eaten. These toxins can cause morbidity and rarely, mortality in humans. Apart from these, swallowing the blood of species such as European eelAnguilla anguillaand European congerConger congermight also cause poisoning. Besides, as there has been an invasion of puffer fish especially on the Turkish Mediterranean and Aegean coasts in recent years, there is a danger in question. Thus, it is very important to particularly draw attention to these fish on the Turkish coasts.

  18. Vaccination in Fish

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar

    significant losses in aquacultural enterprises but vaccination methods implemented since the 1990s have demonstrated their role as one of the most efficient disease control strategies. These have been particularly successful with regard to bacterial diseases in Norwegian salmon farming where multivalent...... vaccines have reduced the need for usage of antibiotics with more than 99 % since the 1980s. Fish can be vaccinated by three different administration routes: injection, immersion and oral vaccination. Injection vaccination (intraperitoneal injection of vaccine) is the most time consuming and labor...... intensive method, which however, provides the best protection of the fish. Immersion vaccination is used for immunization of a high number of small fish is cost-efficient and fast (30 sec immersion into vaccine). Oral vaccination (vaccine in feed) is the least efficient. As in higher vertebrates fish...

  19. West Coast Fishing Ethnography

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Created as part of a 2012 BOEM study on OCS renewable energy space-use conflicts, this data contains the commercial and recreational fishing locations off the...

  20. Dehydrofreezing of Fish I

    Science.gov (United States)

    Kozima, Tsuneo

    Recently, new method of removing water from perishable food were developed using dehydration sheet with material having high osmotic pressure and absorbent polymer. Dehydration sheet consist of mixture of sugar dehydrolysate and absorbent polymer covered with sem-permeable membrane, and can remove water in liquid state by contact with perishable food. Dehydration rate of fish using with dehydration sheet varied depending on species, their shape, and ambient temperature etc. Fish were dehydrated with dehydration sheet at low temperature as 0 - 5 C and frozen in cold storage room. Dehydrofrozen fish were kept it's high quality and freshness after thawing, ATPase activity of fish muscle was kept at high level after dehydrofreezing in the case of cod and alaska pollack, and flesh color of farming salmon was kept after thawing.

  1. Meat, Poultry and Fish

    Science.gov (United States)

    ... mackerel, lake trout, herring, sardines, albacore tuna and salmon. Some types of fish may contain high levels ... cholesterol. However, liver is rich in iron and vitamins. A small serving (3 ounces) is OK about ...

  2. Fishing Community Profiles

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To enable fisheries managers to comply with National Standard 8 (NS8), NMFS social scientists around the nation are preparing fishing community profiles that present...

  3. Ciguatera Fish Poisoning

    Science.gov (United States)

    ... debilitating (Miller, 1991). To date there is no antidote or effectivc treatment, so supportive care and medications ... Diagnosis, Management and Treatment, Chemical Structure, and Molecular Mechanism of Action. Additional Resources Ciguatera Fish Poisoning: Treatment, ...

  4. Combating Illegal Fishing

    National Research Council Canada - National Science Library

    Sorin Stanciu; Andrea Feher

    2010-01-01

    Illegal, unreported and unregulated (IUU) fishing is a worldwide phenomenon. Its extent and its environmental,economic and social consequences are such that it has become a priority issue at international level...

  5. SIS - Fish Assessment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Fish Assessment data set within the Species Information System (SIS) constraints information related to fishery stock assessments, including assessment meta-data...

  6. Fish germ cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fish, like many other animals, have two major cell lineages, namely the germline and soma. The germ-soma separation is one of the earliest events of embryonic development. Germ cells can be specifically labeled and isolated for culture and transplan-tation, providing tools for reproduction of endangered species in close relatives, such as surrogate production of trout in salmon. Haploid cell cultures, such as medaka haploid embryonic stem cells have recently been obtained, which are capable of mimicking sperm to produce fertile offspring, upon nuclear being directly transferred into normal eggs. Such fish originated from a mosaic oocyte that had a haploid meiotic nucleus and a transplanted haploid mitotic cell culture nucleus. The first semi-cloned fish is Holly. Here we review the current status and future directions of understanding and manipulating fish germ cells in basic research and reproductive technology.

  7. The Optimal Fishing Pattern

    NARCIS (Netherlands)

    Kolding, J.; Law, R.; Plank, M.; Zwieten, van P.A.M.

    2016-01-01

    Conventional fisheries management encourages highly selective fishing patterns for various purposes, such as increase relative yield, reduce unwanted bycatch, protect various species or sizes and rebuild ecosystems. Recent empirical and theoretical studies, however, show increasing evidence that

  8. Larval fish nutrition

    National Research Council Canada - National Science Library

    Holt, J

    2011-01-01

    ... introduction to fish micronutrient history 4.2 Micronutrients in larval feeds 4.3 Requirements versus recommendations 4.4 Vitamins 4.5 Minerals 34.6 Future challenges Section 2: Nutritional Physi...

  9. Pedigree Go Fish

    National Research Council Canada - National Science Library

    Michael V. Osier

    2017-01-01

    A card game based upon the classic game Go Fish is presented for active practicing of segregation analysis, the determination of the most likely method of transmission based upon pedigree information...

  10. Senescence in fishes

    Energy Technology Data Exchange (ETDEWEB)

    Woodhead, A.D.

    1979-01-01

    A long-standing theory, that there is a fundamental difference in aging between fishes and higher vertebrates, is still alive in the minds of many. In 1932, Bidder proposed that aging was causatively related to the cessation of growth at sexual maturity. Fish, which continue to grow throughout their lives, would not age, and therefore were potentially immortal. His ideas were clearly disproven by Comfort, who established that the survival curves of a laboratory population of guppies, Poecilia reticulata, were very similar to those of a small mammal population under laboratory conditions. Recent data from field and laboratory studies, including histological evidence, amply confirm the occurrence of senescence in fishes. Natural death in fish has been associated with reproduction. There is good evidence for a number of species which shows that, with increasing size, the gonad forms a greater proportion of total body weight. In older, larger fish, extensive energy depletion for reproduction is suggested as an important factor in mortality. Reproductive modifications in older fish are also noted.

  11. Fish cardiovascular physiology and disease.

    Science.gov (United States)

    Sherrill, Johanna; Weber, E Scott; Marty, Gary D; Hernandez-Divers, Stephen

    2009-01-01

    Fish patients with cardiovascular disorders present a challenge in terms of diagnostic evaluation and therapeutic options. Veterinarians can approach these cases in fish using methods similar to those employed for other companion animals. Clinicians who evaluate and treat fish in private, aquarium, zoologic, or aquaculture settings need to rely on sound clinical judgment after thorough historical and physical evaluation. Pharmacokinetic data and treatments specific to cardiovascular disease in fish are limited; thus, drug types and dosages used in fish are largely empiric. Fish cardiovascular anatomy, physiology, diagnostic evaluation, monitoring, common diseases, cardiac pathologic conditions, formulary options, and comprehensive references are presented with the goal of providing fish veterinarians with clinically relevant tools.

  12. Epigenomics in marine fishes.

    Science.gov (United States)

    Metzger, David C H; Schulte, Patricia M

    2016-12-01

    Epigenetic mechanisms are an underappreciated and often ignored component of an organism's response to environmental change and may underlie many types of phenotypic plasticity. Recent technological advances in methods for detecting epigenetic marks at a whole-genome scale have launched new opportunities for studying epigenomics in ecologically relevant non-model systems. The study of ecological epigenomics holds great promise to better understand the linkages between genotype, phenotype, and the environment and to explore mechanisms of phenotypic plasticity. The many attributes of marine fish species, including their high diversity, variable life histories, high fecundity, impressive plasticity, and economic value provide unique opportunities for studying epigenetic mechanisms in an environmental context. To provide a primer on epigenomic research for fish biologists, we start by describing fundamental aspects of epigenetics, focusing on the most widely studied and most well understood of the epigenetic marks: DNA methylation. We then describe the techniques that have been used to investigate DNA methylation in marine fishes to date and highlight some new techniques that hold great promise for future studies. Epigenomic research in marine fishes is in its early stages, so we first briefly discuss what has been learned about the establishment, maintenance, and function of DNA methylation in fishes from studies in zebrafish and then summarize the studies demonstrating the pervasive effects of the environment on the epigenomes of marine fishes. We conclude by highlighting the potential for ongoing research on the epigenomics of marine fishes to reveal critical aspects of the interaction between organisms and their environments. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Immunity to Fish Rhabdoviruses

    Directory of Open Access Journals (Sweden)

    Maureen K. Purcell

    2012-01-01

    Full Text Available Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M protein to mediate host-cell shutoff and the non‑virion (NV protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  14. Freshwater and fish

    Energy Technology Data Exchange (ETDEWEB)

    Saxen, R. [Finnish Centre for Radiation and Nuclear Safety (Finland)

    1997-10-01

    Severe radioactive contamination of the freshwater environment could have serious consequences for both drinking water and fish. Most of the Nordic countries have an abundance of freshwater lakes and rivers. Finland alone has about 56,000 lakes, each with a surface area of 1 hectare or more. Nearly 10% of Finland`s surface is covered with lakes and rivers. In Sweden, about 9% of the surface area is freshwater, in Norway about 5%, and in Denmark only about 2%. Freshwater plays a minor role in Iceland, but even there numerous rivers discharge from the volcanic soils to the Ocean. Cs-137 and {sup 90}Sr are likely to be the most important radionuclides with respect to long term radioactive contamination of freshwater. If radioactive deposition occurs in the absence of snow and ice radionuclides will contaminate the surface water directly and may rapidly enter the aquatic food chain. Fish which eat contaminated plankton become contaminated almost immediately. Deposition during summer increases the transfer for radionuclides to fish since fish metabolism is faster during the warm season. During the cold period, fish metabolism is slow and thus uptake and excretion of radiocaesium are also slow. (EG). 18 refs.

  15. Immunity to fish rhabdoviruses

    Science.gov (United States)

    Purcell, Maureen K.; Laing, Kerry J.; Winton, James R.

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non-virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  16. Can Fish Catch On in Your Class?

    Science.gov (United States)

    Butzow, John W.; Kane, Philip N.

    1983-01-01

    Presented are several classroom activities using fish. These include gyotaku (Japanese fish printing), use of a dichotomous key to classify fish, "invent-a-fish" activities, and others. Includes discussion of fish facts and copies of fish key and invent-a-fish cards. (JN)

  17. [Ciguatera fish poisoning].

    Science.gov (United States)

    Oehler, Erwan; Bouchut, Jérémie

    2014-09-01

    Ciguatera, an ichtyosarcotoxism linked to the consumption of usually healthy coral fish is a common poisoning in the Pacific, Caribbean and Indian Ocean where it is endemic. However, increased tourism and commercial transportation of tropical fish for consumption make it an unexceptional intoxication in countries away from its endemic area. Environmental stresses such as climate changes also contribute to the expansion of its geographical area. The non-specific clinical symptomatology is characterized by the occurrence of gastrointestinal, cardiovascular, nervous and general signs few hours after eating a ciguatoxic fish. The diagnosis is clinical and relatively easy in endemic areas but much less for physicians who are rarely confronted with, which is a source of prolonged diagnostic delays and a significant increase in spending. Treatment of ciguatera is symptomatic but new treatments, still experimental, give a real hope for the future.

  18. Dynamite fishing in Tanzania.

    Science.gov (United States)

    Slade, Lorna M; Kalangahe, Baraka

    2015-12-30

    Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private-public partnerships for patrol and protection.

  19. Jurassic fishes of Gondwana

    Directory of Open Access Journals (Sweden)

    Adriana López-Arbarello

    2008-12-01

    Full Text Available The Jurassic is an important period for understanding the origin of modern fish faunas, since it saw the first radiation - and in some cases the origin - of most modern groups. In chondrichthyans, neoselachian sharks and rays diversified during this time. In actinopterygians, the neopterygians, and among them the teleosts, experienced an important radiation, which led to the appearance of several of the modern teleosts groups. In the sarcopterygians, dipnoans and actinistians approached their current forms. However, the Jurassic fossil record of fishes is strongly biased towards the Northern Hemisphere. The only notable Early Jurassic fish fauna from Gondwana is that of the Kota Formation of India. For the Middle Jurassic, the most important Gondwanan fish faunas are those of the Aalenian-Bathonian Stanleyville Beds of the Democratic Republic of Congo, in which a distinct freshwater and a marine fauna are found. In the Late Jurassic, the Gondwanan record is slightly better, with important marine faunas being known from the Oxfordian Quebrada del Profeta in Chile and the Tithonian Vaca Muerta Formation of Argentina. Freshwater faunas have been described from the Tithonian Talbragar Beds of eastern Australia and the Tithonian Cañadón Calcáreo Formation of Argentina. The taxonomic composition of the known marine actinopterygian faunas of Gondwana is in general agreement with faunas of the Northern Hemisphere. However, the Jurassic fish record from Gondwana is highly incomplete both stratigraphically and geographically, and most faunas are in need of revision, further hampering an interpretation of Jurassic fish evolution in the Southern Hemisphere.

  20. Fish remains and humankind

    Directory of Open Access Journals (Sweden)

    Andrew K G Jones

    1997-08-01

    Full Text Available The four papers in this issue represent a trawl of the reports presented to the Fourth meeting of the International Council for Archaeozoology (ICAZ Fish Remains Working Group, which met at the University of York in 1987. The conference discussed material from many parts of the world - from Australasia to the north-west coast of America - and many eras, ranging in date from the early Pleistocene to the 1980s. It demonstrated both the variety of work being carried out and the growing interest in ancient fish remains. Internet Archaeology plans to publish other batches of papers from this conference. These reports will demonstrate the effort being made to distinguish between assemblages of fish remains which have been deposited by people and those which occur in ancient deposits as a result of the action of other agents. To investigate this area, experiments with modern material and observations of naturally occurring fish bone assemblages are supplemented with detailed analysis of ancient and modern fish remains. The papers published here illustrate the breadth of research into osteology, biogeography, documentary research, and the practicalities of recovering fish remains. Read, digest and enjoy them! Using the Internet for publishing research papers is not only ecologically sound (saving paper, etc. it disseminates scholarship to anyone anywhere on the planet with access to what is gradually becoming necessary technology in the late 20th century. Hopefully, future groups of papers will include video and audio material recorded at the conference, and so enable those who could not attend to gain further insights into the meeting and the scholarship underpinning this area of research.

  1. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  2. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  3. Fish Hatchery Management in Nigeria

    Directory of Open Access Journals (Sweden)

    J.A. Akankali

    2011-04-01

    Full Text Available Fish hatchery management is efficient tool in intensive fish culture. The vital requirements of fish hatchery, hatchery construction, concrete tank construction, nursery, rearing and production ponds, fish seed hatchery, hormone in fish spawning, hypophysation, compounds used for induced breeding, hormone administration, spawning and rearing, steps in artificial propagation, hatchery management, nursery management are basic elements in effective hatchery management. The article reviews these vital elements to re-awaken fish farmers, Fisheries students private and public sectors in the formulation of fisheries policies.

  4. Simultaneous RNA-DNA FISH.

    Science.gov (United States)

    Lai, Lan-Tian; Meng, Zhenyu; Shao, Fangwei; Zhang, Li-Feng

    2016-01-01

    A highly useful tool for studying lncRNAs is simultaneous RNA-DNA FISH, which reveals the localization and quantitative information of RNA and DNA in cellular contexts. However, a simple combination of RNA FISH and DNA FISH often generates disappointing results because the fragile RNA signals are often damaged by the harsh conditions used in DNA FISH for denaturing the DNA. Here, we describe a robust and simple RNA-DNA FISH protocol, in which amino-labeled nucleic acid probes are used for RNA FISH. The method is suitable to detect single-RNA molecules simultaneously with DNA.

  5. FishFrame

    DEFF Research Database (Denmark)

    Degel, Henrik; Jansen, Teunis

    2006-01-01

    . Development and test of software modules can be done once and reused by all. The biggest challenge in this is not technical – it is in organisation, coordination and trust. This challenge has been addressed by FishFrame - a web-based datawarehouse application. The “bottom-up” approach with maximum involvement...... value to users and in the end improves the way we work with our data. FishFrame version 4.2 is presented and the lessons learned from the process are discussed....

  6. Fish in Ecotoxicological Studies

    Directory of Open Access Journals (Sweden)

    Vesela Yancheva

    2015-06-01

    Full Text Available Water contamination (heavy metals, pesticides, POPs, etc. is a serious environmental issue which has been raising lots of attention in the last decades because it can destroy aquatic ecosystems and hence, reduce biodiversity. In the field of ecotoxicology it is of main interest to investigate what the effects of organic and inorganic toxicants on different biological organization (cell, tissue, organism, population are. Thus, many authors use different test organisms and particularly, fish. In the current study we aimed to present collected data from the last years which describe why fish is an appropriate species in terms of ecotoxicological research.

  7. Fish and Bird

    Institute of Scientific and Technical Information of China (English)

    毛秀波

    2010-01-01

    人物:B——Bird L——Little Fish M——Mother Fish N——Narracor(旁白)道具:角色头饰 N:一条生活在河里的Little Fish对天空充满了好奇,一心想飞到天空去看看。此时,Little Fish正依偎在Mother Fish身边,好奇地望着天空。

  8. Fish Hold Effluent and Fish Hold Cleaning Wastewater Discharge

    Science.gov (United States)

    2011-11-01

    summarized in Table 1). EPA estimated that mid-size fishing vessels, such as gill netters , and purse seiners found in Alaska, and shrimp boats in the Gulf...size fishing boats such as gill netters , fish holds are typically cleaned using a garden hose at a flow rate of approximately 10 to 12 gpm (USEPA...Small: salmon trollers and longliners 1,500 Daily when fishing 500 - 600 150 - 200 Mid-size: gill netters , purse seiners and shrimp boats

  9. Fish and fish oil in health promotion and disease prevention

    Science.gov (United States)

    Fish is an important dietary component due to its contribution of valuable nutrients. In addition to the high quality protein and micronutrients provided, fish is the primary source of long-chain omega-3 fatty acids which are found in oils of ‘fatty’ cold water fish. Biomedical evidence supports th...

  10. Fish Commoditization: Sustainability Strategies to Protect Living Fish

    Science.gov (United States)

    Lam, Mimi E.; Pitcher, Tony J.

    2012-01-01

    The impacts of early fishing on aquatic ecosystems were minimal, as primitive technologies were used to harvest fish primarily for food. As fishing technology grew more sophisticated and human populations dispersed and expanded, local economies transitioned from subsistence to barter and trade. Expanded trade networks and mercantilization led to…

  11. Significant Effects of Fishing Gear Selectivity on Fish Life History

    Institute of Scientific and Technical Information of China (English)

    LIANG Zhenlin; SUN Peng; YAN Wei; HUANG Liuyi; TANG Yanli

    2014-01-01

    Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller size-at-age, an earlier age-at-maturation and among others. Currently, the causes of these life history traits changes still require systematic analyses and empirical studies. The explanations that have been cited are merely expressed in terms of fish phenotypic adaptation. It has been claimed that the original traits of fish can be recovered once the intensity of exploitation of the fish is controlled. Sustained environmental and fishing pressure will change the life history traits of most fish species, so the fish individual’s traits are still in small size-at-age and at earlier age-at-maturation in exploited fish populations. In this paper, we expressed our view of points that fishing gear has imposed selectiv-ity on fish populations and individuals as various other environmental factors have done and such changes are unrecoverable. Ac-cording to the existing tend of exploited fish individual’s life history traits, we suggested further researches in this field and provided better methods of fishery management and thereby fishery resources protection than those available early.

  12. Fish Springs weather CY 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Weather data for calendar year 2011 at Fish Springs National Wildlife Refuge. Data is provided for each month and includes maximum temperature, minimum temperature,...

  13. Fish Springs weather CY 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Weather data for calendar year 2010 at Fish Springs National Wildlife Refuge. Data is provided for each month and includes maximum temperature, minimum temperature,...

  14. Anadromous fish inventory: Summary volume

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Summary volume, with discussion, on anadromous fish inventories, species lists, histories of fisheries, habitat, key spawning and rearing areas, runs/escapements,...

  15. KLA - Live Hauling of Fish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In certain markets, live fish can be sold for substantially higher prices than fresh dressed fish. A significant live-haul industry has developed in the U.S. and...

  16. LCA of Danish fish products

    DEFF Research Database (Denmark)

    Thrane, Mikkel

    2006-01-01

    The article presents the main results from a PhD dissertation about environmental impacts from Danish fish products.......The article presents the main results from a PhD dissertation about environmental impacts from Danish fish products....

  17. Report on Fish Springs - 1958

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document discusses field survey results from several trips to Fish Springs National Wildlife Refuge during the summer of 1958. The following information is...

  18. Fish Culture Economics and Extension

    Directory of Open Access Journals (Sweden)

    E.N. Ogamba

    2012-12-01

    Full Text Available Fish culture economics and extension was reviewed to enable fish culturist plan effectively before involved in fish culture and practices. The cost and benefits of fish culture need be known before participation in the business. There is need for cross-link between research and the fishing community. Prior to introduction of any new innovation in fisheries extension and evaluation of such programmers, the agency responsible for such exercise should have full knowledge of the existing farming practice/techniques and the reasons behind them. In assessing or evaluating the impact of any new techniques or programmers, consideration should be given to such factors as natural conditions, local infrastructures, socio cultural setting, farmers’ production aims and labor economics. The study reviews the types of feasibility study, a typical feasibility study and report on a fish farm project and detail analysis of culture extension to enable fish culturist plan effectively before involved in fish culture and practices.

  19. Temperature - Live Hauling of Fish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In certain markets, live fish can be sold for substantially higher prices than fresh dressed fish. A significant live-haul industry has developed in the U.S. and...

  20. The fish egg microbiome

    NARCIS (Netherlands)

    Liu, Y.

    2016-01-01

    Y. Liu Prof. dr. F. Govers (promotor); Prof. dr. J.M. Raaijmakers (promotor); Dr. I. de Bruijn (co-promotor); Wageningen University, 13 June 2016, 170 pp. The fish egg microbiome: diversity and activity against the oomycete pathogen Saprolegnia Emerging oomycete pat

  1. Fish in Mutton

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    Ingredients:500 grams mutton and 750 grams live fish Condiments:Salt for taste, ginger, scallion, soup, water chestnut powder, gourmet powder Method: 1.Quick-boil the clean mutton. then put scallion, ginger, salt, gourmet powder and pepper powder into it and cook until

  2. The fish egg microbiome

    NARCIS (Netherlands)

    Liu, Y.

    2016-01-01

    Y. Liu Prof. dr. F. Govers (promotor); Prof. dr. J.M. Raaijmakers (promotor); Dr. I. de Bruijn (co-promotor); Wageningen University, 13 June 2016, 170 pp. The fish egg microbiome: diversity and activity against the oomycete pathogen Saprolegnia Emerging oomycete

  3. Yet Another Fish Tale?

    Science.gov (United States)

    Lalasz, Robert

    2008-01-01

    Last month the "Rocky Mountain News" reported that a survey by an emeritus professor at University of Colorado Boulder found that only 23 of 825 faculty members on the campus were registered Republicans. But on his "New York Times" blog, Stanley Fish brushed off the survey's significance from a familiarly Fishian stance. A faculty's political…

  4. Access and Fishing Activities

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2015-01-01

    a detailed ethnographic description of five different fishing operations and then compare them on a number of different fronts. This will direct us to some general differences in their modes of operation in relation to the vessel quota share (VQS) system and lead us to the next chapter, where the principal...... implications of the VQS for different modes of production will be discussed....

  5. Access and Fishing Activities

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2015-01-01

    In this chapter, I look at the implications of transferable quotas on the organization of production; that is, how fishing activities are structured around access to the individual and transferable quotas and how, in turn, the quotas structure the production. Therefore, this chapter will give...

  6. ChillFish

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    2016-01-01

    Breathing exercises can help children with ADHD control their stress level, but it can be hard for a child to sustain attention throughout such an exercise. In this paper, we present ChillFish, a breath-controlled biofeedback game designed in collaboration with ADHD professionals to investigate...

  7. FishTraits Database

    Science.gov (United States)

    Angermeier, Paul L.; Frimpong, Emmanuel A.

    2009-01-01

    The need for integrated and widely accessible sources of species traits data to facilitate studies of ecology, conservation, and management has motivated development of traits databases for various taxa. In spite of the increasing number of traits-based analyses of freshwater fishes in the United States, no consolidated database of traits of this group exists publicly, and much useful information on these species is documented only in obscure sources. The largely inaccessible and unconsolidated traits information makes large-scale analysis involving many fishes and/or traits particularly challenging. FishTraits is a database of >100 traits for 809 (731 native and 78 exotic) fish species found in freshwaters of the conterminous United States, including 37 native families and 145 native genera. The database contains information on four major categories of traits: (1) trophic ecology, (2) body size and reproductive ecology (life history), (3) habitat associations, and (4) salinity and temperature tolerances. Information on geographic distribution and conservation status is also included. Together, we refer to the traits, distribution, and conservation status information as attributes. Descriptions of attributes are available here. Many sources were consulted to compile attributes, including state and regional species accounts and other databases.

  8. Lemongrass-Fried Fish

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Ingredients: 500 grams grass carp, several stalks of lemongrass, 5 leaves of lettuce. Condiments: 10 grams sweet sauce (made from fermented flour, scallion powder and ginger root powder); yolk of one egg, cooking wine, salt, pepper and MSG (optional). Method: 1. Cut the fish into pieces. Mash

  9. Hydrodynamics of fossil fishes.

    Science.gov (United States)

    Fletcher, Thomas; Altringham, John; Peakall, Jeffrey; Wignall, Paul; Dorrell, Robert

    2014-08-07

    From their earliest origins, fishes have developed a suite of adaptations for locomotion in water, which determine performance and ultimately fitness. Even without data from behaviour, soft tissue and extant relatives, it is possible to infer a wealth of palaeobiological and palaeoecological information. As in extant species, aspects of gross morphology such as streamlining, fin position and tail type are optimized even in the earliest fishes, indicating similar life strategies have been present throughout their evolutionary history. As hydrodynamical studies become more sophisticated, increasingly complex fluid movement can be modelled, including vortex formation and boundary layer control. Drag-reducing riblets ornamenting the scales of fast-moving sharks have been subjected to particularly intense research, but this has not been extended to extinct forms. Riblets are a convergent adaptation seen in many Palaeozoic fishes, and probably served a similar hydrodynamic purpose. Conversely, structures which appear to increase skin friction may act as turbulisors, reducing overall drag while serving a protective function. Here, we examine the diverse adaptions that contribute to drag reduction in modern fishes and review the few attempts to elucidate the hydrodynamics of extinct forms.

  10. Fish Facts. Lesson Plan.

    Science.gov (United States)

    Chan, Mike

    This lesson plan is designed for a 50-minute class to teach extension home economists and homemakers about buying, storing, and using fish. The lesson plan contains references, a list of equipment needed, objectives, and the presentation. The presentation consists of an outline of instruction coordinated with methods of instruction and aids and…

  11. How to Represent a Fish?

    Directory of Open Access Journals (Sweden)

    Elspeth Probyn

    2017-05-01

    Full Text Available This article canvasses a broad range of fish representations across several disciplines. It asks what cultural studies can learn from scientific representation of fish, and argues that in turn cultural studies can be a nuanced understanding of the work of images. The objective of the article is to open debate about fish and their sustainability beyond discrete disciplines and/or ideologies. This, it is argued, is crucial if we are to go beyond a simplified cultural politics of fish.

  12. Fish passage report : Baca National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This fish passage report was prepared for the Colorado Fish and Wildlife Conservation Office to inform them of possible fish passage issues on streams that provide...

  13. BIOTECHNOLOGY OF THE FISH AQUACULTURE

    Directory of Open Access Journals (Sweden)

    L. P. Buchatsky

    2013-12-01

    Full Text Available The latest progress in biotechnology on fish aquaculture and different modern methods of investigations for increasing of fish productivity in aquaculture are analyzed. Except for the applied aspect, the use of modern biotechnological methods of investigations opens new possibilities for fundamental researches of sex-determining mechanisms, polyploidy, distant hybridization, and developmental biology of bony fishes. Review contains examples of utilizing modern biotechnology methods to obtain transgenic fishes with accelerated growth and for designing surrogate fishes. Methods for receiving unisexual shoals of salmon and sturgeon female fishes with the view of obtaining a large quantity of caviar, as well as receiving sterile (triploid fishes are analyzed. Great attention is given to androgenesis, particularly to disperm one, in connection with the problem of conserving rare and vanishing fish species using only sperm genetic material. Examples how distant hybrids may be obtained with the use of disperm androgenesis and alkylated DNA are given. Methods of obtaining fish primordium germ cells, recent developments in cultivation of fish stem cells and their use in biotechnology, as well as ones of transplantation of oogonium and spermatogonium to obtain surrogate fishes. The examples of successful experiments on spermatogonial xenotransplantation and characteristic of antifreezing fish proteins and also the prospect of their practical usage are given.

  14. Plastic in North Sea Fish

    NARCIS (Netherlands)

    Foekema, E.M.; Gruijter, de C.; Mergia, M.T.; Franeker, van J.A.; Murk, A.J.; Koelmans, A.A.

    2013-01-01

    To quantify the occurrence of ingested plastic in fish species caught at different geographical positions in the North Sea, and to test whether the fish condition is affected by ingestion of plastics, 1203 individual fish of seven common North Sea species were investigated: herring, gray gurnard, wh

  15. Fish freshness rapid detection based on fish-eye image

    Science.gov (United States)

    Wang, Feng; Zang, Yue; Wo, Qiqi; Zou, Chen; Wang, Nan; Wang, Xiaobo; Li, Dadong

    Study a new method for detecting fish freshness. During the experiment, we choose freshest fish-eyes images via digital camera to add computing the synthesis of the latest fish-eye image .Next figure out every image's signal strength. Finally, we analysis relation between the change of the image's energy and the value (pH, electrical conductivity, TVBN) by Modeling of Partial Least Squares Regression. The result shows that we can detect freshness of fish quickly, conveniently, simply and accurately through the fish-eye image energy change.

  16. KARAKTERISTIK SUMBERDAYA IKAN DAN STRATEGI PENGELOLAAN PERIKANAN PERAIRAN SUNGAI YANG BERMUARA KE PANTAI BARAT SUMATERA

    Directory of Open Access Journals (Sweden)

    Husnah Husnah

    2012-11-01

    Manna dan Suoh di Sungai Semangka. Alternatif pengelolaan lainnya adalah peningkatan produksi ikan Semah melalui restocking induk ataupun benih. Fisheries management practices such as allocation of fish resources utilization and permitted total fish catch in marine and inland waters relate to the characteristic of fish resources. Geomorphplogical condition as well as fish resources and fisheries of rivers flow through to the western Sumatra estuary such as Manna River and Semangka River are different from the rivers flow through to eastern Sumatra estuary. Information on characteristic and management of fish resources in these rivers is limited while there is indication declining fish catch in these rivers. This paper discribed characteristic and management of Manna and Semangka rivers based on a study conducted in 2011. Rivers flow through to the western part of Sumatra estuary are characterized by constrained shape rivers, low habitat and fish diversity, low fish yield, subsistence fisheries and with two important economical fish such as carps (Tor sp and eels (Anguilla sp. In addition to forest clearance at the upper stream, population of these fish were mostly threaten by illegal fishing such us application of electro fishing and poison. Desimination of about prohibition operation of unfriendly fishing gears has been conducted by the local government, however it does not followed by implementing the law enforcement. The fisheries management of Manna and Semangka rivers should be based on the integration and responsible principle and should be focused on the habitat and population of the two economical fish. The alternative fisheries management strategies are in situ conservation such as establishment of fisheries reserves situated at the river pools specially the site area with abundant fish fries and fish brooders such as in Air Tenam Manna River and Suoh in Semangka River. Enhancing of fish stock through restocking fish at fry and brooder size is other management

  17. Fishery and Aquaculture Relationship in the Mediterranean: Present and Future

    Directory of Open Access Journals (Sweden)

    G. RELINI

    2012-12-01

    Full Text Available Although the Mediterranean represents only 0.8% of the world seas, it is the site of a very long-established fishing activity, characterized mainly by multispecific catch and by artisanal or coastal activity, resulting from a mosaic of very diversified structures and gears, along more than 45,000 km of coastline. Two main biological features of this sea are the occurrence of a large richness of species (it represents 5.5% - 7% of world marine fauna and 16.6% of macrophyta, which stands in contrast with its ‘trophic poverty’ and the absence of large monospecific fishery, except for some small and large pelagic fish. Another biological characteristic of Mare Nostrumis the high invasion of exotic species, some exploited by fishery and aquaculture, some others quite dangerous. For the entire Mediterranean and Black Sea, the production (catch + aquaculture had been steadily increasing over the period 1972-1988 from 1,140,000 t to 2,080,000 t . The period 1988-1991 has shown a drastic drop in catches (in 1991: 1,400,000 t. From 1990 to 1995 the total catch increased to 1,701,379 t then decreased and in 2000 reached 1,485,046 t . In 2000 Turkey had the first place with 496,174 t, 26.9% of the total value (1,846,026 t, including fishing and aquaculture, followed by Italy with 25%, Greece 9%, Spain 7.6% and Algeria 5.4%. As in many parts of the world, aquaculture production in the Mediterranean is rapidly expanding. In 1970 the total aquaculture production was about 18,297 t of which 74.3% produced in Italy. In 2000 a value of 358,614 t was reached, about 1/4 of the total fishery catch, while the world aquaculture production corresponds to half of the world total catch. Italy is still the main producer with 46.7% , followed by Greece with 21.5%, Turkey 9.9% and France 6.7%. A sharp drop in the production of the European eel ( Anguilla anguilla and of the European flat oyster ( Ostrea edulis is recorded. Positive and negative interactions between

  18. Fishery and Aquaculture Relationship in the Mediterranean: Present and Future

    Directory of Open Access Journals (Sweden)

    G. RELINI

    2003-12-01

    Full Text Available Although the Mediterranean represents only 0.8% of the world seas, it is the site of a very long-established fishing activity, characterized mainly by multispecific catch and by artisanal or coastal activity, resulting from a mosaic of very diversified structures and gears, along more than 45,000 km of coastline. Two main biological features of this sea are the occurrence of a large richness of species (it represents 5.5% - 7% of world marine fauna and 16.6% of macrophyta, which stands in contrast with its ‘trophic poverty’ and the absence of large monospecific fishery, except for some small and large pelagic fish. Another biological characteristic of Mare Nostrumis the high invasion of exotic species, some exploited by fishery and aquaculture, some others quite dangerous. For the entire Mediterranean and Black Sea, the production (catch + aquaculture had been steadily increasing over the period 1972-1988 from 1,140,000 t to 2,080,000 t . The period 1988-1991 has shown a drastic drop in catches (in 1991: 1,400,000 t. From 1990 to 1995 the total catch increased to 1,701,379 t then decreased and in 2000 reached 1,485,046 t . In 2000 Turkey had the first place with 496,174 t, 26.9% of the total value (1,846,026 t, including fishing and aquaculture, followed by Italy with 25%, Greece 9%, Spain 7.6% and Algeria 5.4%. As in many parts of the world, aquaculture production in the Mediterranean is rapidly expanding. In 1970 the total aquaculture production was about 18,297 t of which 74.3% produced in Italy. In 2000 a value of 358,614 t was reached, about 1/4 of the total fishery catch, while the world aquaculture production corresponds to half of the world total catch. Italy is still the main producer with 46.7% , followed by Greece with 21.5%, Turkey 9.9% and France 6.7%. A sharp drop in the production of the European eel ( Anguilla anguilla and of the European flat oyster ( Ostrea edulis is recorded. Positive and negative interactions between

  19. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  20. Metazoan Parasites of Antarctic Fishes.

    Science.gov (United States)

    Oğuz, Mehmet Cemal; Tepe, Yahya; Belk, Mark C; Heckmann, Richard A; Aslan, Burçak; Gürgen, Meryem; Bray, Rodney A; Akgül, Ülker

    2015-06-01

    To date, there have been nearly 100 papers published on metazoan parasites of Antarctic fishes, but there has not yet been any compilation of a species list of fish parasites for this large geographic area. Herein, we provide a list of all documented occurrences of monogenean, cestode, digenean, acanthocephalan, nematode, and hirudinean parasites of Antarctic fishes. The list includes nearly 250 parasite species found in 142 species of host fishes. It is likely that there are more species of fish parasites, which are yet to be documented from Antarctic waters.

  1. Diet of non-native northern snakehead (Channa argus) compared to three co-occurring predators in the lower Potomac River, USA

    Science.gov (United States)

    Ryan K. Saylor,; Nicolas W.R. Laointe,; Angermeier, Paul

    2012-01-01

    Introductions of large, non-native, carnivorous fishes continue to occur worldwide and represent a substantial management concern to global biodiversity. One of the most recent non-native fishes to successfully establish in North America is the northern snakehead (Channa argus), found in the lower Potomac River catchment. Dispersal of the northern snakehead throughout this system has been well documented since its original discovery in May 2004; however, little is known about the foraging habits of this species and its interactions with co-occurring predators. Here, we quantify northern snakehead diet in comparison with the diets of naturalised largemouth bass (Micropterus salmoides), and native American eel (Anguilla rostrata) and yellow perch (Perca flavescens) collected from tidal freshwaters bordering Virginia and Maryland near Fort Belvoir, Virginia. Over 97% of northern snakehead gut contents were fishes, with fundulid and centrarchid species consumed most frequently. Dietary overlap was biologically significant only between northern snakehead and largemouth bass. Aquatic invertebrates were >10 times more common in native predator diets, reducing dietary overlap with northern snakehead. Ontogenic shifts in adult northern snakehead diet were also detected, which may be explained by optimal foraging rather than true prey specificity. Northern snakehead may be occupying a novel niche based on a piscivorous diet, therefore limiting competition with resident predators in the lower Potomac River. Further research into interactions between largemouth bass and northern snakehead is needed to inform management decisions and understand the ecological impacts of this non-native species.

  2. Consumers’ attitude towards fish meat

    Directory of Open Access Journals (Sweden)

    Francesca Conte

    2014-09-01

    Full Text Available The overall aim of this paper is to show the factors that may affect consumers’ attitude towards farmed fish products. Consumers ask new products on the basis of different quality attributes: stability, safety, composition, better health effects, environment protection, etc. Different and controversial opinions on farmed and wild fish are also explored by literature review. The authors pay attention also to fish welfare as an emerging issue and effective information about fish products as a factor exerting a positive influence on consumers’ decision of purchase. Some relevant legislative notes on the paper’s topics are also cited. The qualitative aspects of aquaculture fish and the consumers’ demand and choice need further studies, according to some factors, such as the changing consumers’ attitudes towards fish products, the different fish quality perception and the development in the aquaculture systems.

  3. Speciation in fishes.

    Science.gov (United States)

    Bernardi, Giacomo

    2013-11-01

    The field of speciation has seen much renewed interest in the past few years, with theoretical and empirical advances that have moved it from a descriptive field to a predictive and testable one. The goal of this review is to provide a general background on research on speciation as it pertains to fishes. Three major components to the question are first discussed: the spatial, ecological and sexual factors that influence speciation mechanisms. We then move to the latest developments in the field of speciation genomics. Affordable and rapidly available, massively parallel sequencing data allow speciation studies to converge into a single comprehensive line of investigation, where the focus has shifted to the search for speciation genes and genomic islands of speciation. We argue that fish present a very diverse array of scenarios, making them an ideal model to study speciation processes.

  4. Herpesviruses that Infect Fish

    Directory of Open Access Journals (Sweden)

    Moshe Kotler

    2011-11-01

    Full Text Available Herpesviruses are host specific pathogens that are widespread among vertebrates. Genome sequence data demonstrate that most herpesviruses of fish and amphibians are grouped together (family Alloherpesviridae and are distantly related to herpesviruses of reptiles, birds and mammals (family Herpesviridae. Yet, many of the biological processes of members of the order Herpesvirales are similar. Among the conserved characteristics are the virion structure, replication process, the ability to establish long term latency and the manipulation of the host immune response. Many of the similar processes may be due to convergent evolution. This overview of identified herpesviruses of fish discusses the diseases that alloherpesviruses cause, the biology of these viruses and the host-pathogen interactions. Much of our knowledge on the biology of Alloherpesvirdae is derived from research with two species: Ictalurid herpesvirus 1 (channel catfish virus and Cyprinid herpesvirus 3 (koi herpesvirus.

  5. Of Fish and Micrornas

    OpenAIRE

    2013-01-01

    Fish is an important small vertebrate multidisciplinary model for investigating various aspects of reproduction, development, disease (immunology, toxicology, carcinogenesis), and aging. It is also an important model for comparative and evolutionary studies because it represents the lower vertebrates and serves as an essential link to early vertebrate evolution. Microribonucleic acids (miRNAs) are 18-22 nucleotide-long endogenous RNAs that bind to specific mRNAs, usually at the 3’-untranslate...

  6. In Place of Fishing

    DEFF Research Database (Denmark)

    Ounanian, Kristen

    Communities historically reliant on fisheries have faced changing circumstances in terms of their livelihoods, identities, demographics, and viabilities. I examine various manifestations of fisheries dependence and the process of transition as related to six cases of fishing communities undergoing...... social, economic, and cultural change. The empirical material for this dissertation comes from interviews in Northern Jutland, Denmark and New England, United States. My purpose in this research was to develop a qualitative baseline of what is happening in different coastal communities to identify...

  7. The interleukins of fish.

    Science.gov (United States)

    Secombes, C J; Wang, T; Bird, S

    2011-12-01

    Interleukins are a subgroup of cytokines, molecules involved in the intercellular regulation of the immune system. The term interleukin was first coined in 1979 to refer to molecules that signal between different leucocyte types, although not exclusively restricted to leucocyte communication. Whilst it is now known that interleukins are produced by a wide variety of cell types, nevertheless many are synthesised by CD4(+) T helper cells, macrophages/monocytes and endothelial cells. The nomenclature is relatively straightforward, with interleukin 1 the first discovered and interleukin 2 the second, etc. However, whilst 35 interleukins are currently described in mammals, several are in fact terms referring to subfamilies of more molecules, as with the IL-1 family where 11 members (IL-1F1-IL-1F11) are present, and the IL-17 family where 6 members (IL-17A-IL-17F) are present. So the total is much higher and splice variants and allelic variation increase this diversity further. This review will focus on what is known about interleukins in fish, and will refer to the major subfamilies rather than try to work through 35 descriptions in a row. It is clear that many direct homologues of molecules known in mammals are present in fish, but that not all are present and some novel interleukins exist that may have arisen from fish specific gene duplication events. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Fish Synucleins: An Update

    Directory of Open Access Journals (Sweden)

    Mattia Toni

    2015-10-01

    Full Text Available Synucleins (syns are a family of proteins involved in several human neurodegenerative diseases and tumors. Since the first syn discovery in the brain of the electric ray Torpedo californica, members of the same family have been identified in all vertebrates and comparative studies have indicated that syn proteins are evolutionary conserved. No counterparts of syns were found in invertebrates suggesting that they are vertebrate-specific proteins. Molecular studies showed that the number of syn members varies among vertebrates. Three genes encode for α-, β- and γ-syn in mammals and birds. However, a variable number of syn genes and encoded proteins is expressed or predicted in fish depending on the species. Among biologically verified sequences, four syn genes were identified in fugu, encoding for α, β and two γ (γ1 and γ2 isoforms, whereas only three genes are expressed in zebrafish, which lacks α-syn gene. The list of “non verified” sequences is much longer and is often found in sequence databases. In this review we provide an overview of published papers and known syn sequences in agnathans and fish that are likely to impact future studies in this field. Indeed, fish models may play a key role in elucidating some of the molecular mechanisms involved in physiological and pathological functions of syn proteins.

  9. Fishing degrades size structure of coral reef fish communities.

    Science.gov (United States)

    Robinson, James P W; Williams, Ivor D; Edwards, Andrew M; McPherson, Jana; Yeager, Lauren; Vigliola, Laurent; Brainard, Russell E; Baum, Julia K

    2017-03-01

    Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra and biomass of coral reef fish communities at 38 US-affiliated Pacific islands that ranged in human presence from near pristine to human population centers. Size spectra 'steepened' steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. Reef fish biomass was substantially lower on inhabited islands than uninhabited ones, even at inhabited islands with the lowest levels of human presence. We found that on populated islands size spectra exponents decreased (analogous to size spectra steepening) linearly with declining biomass, whereas on uninhabited islands there was no relationship. Size spectra were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to oceanographic conditions, being influenced by both oceanic productivity and sea surface temperature. Our results suggest that community size structure may be a more robust indicator than fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems. © 2016

  10. [Biological value of protein from raw fish and canned fish].

    Science.gov (United States)

    Ganoviak, Z M; Lipka, E M

    1983-01-01

    The authors evaluated the nutritive value of protein from 4 kinds of raw fish (herring, cod, mackerel, sprat) and its preserves. Experiments were made on rats fed the diets containing fish protein (8-10% of the total diet). Experiments included the determination of apparent and genuine digestibility, net protein utilization, and net dietary protein caloric value. Evidence was obtained that protein from fish and its preserves is characterized by high digestibility coefficient as compared with casein and egg powder. The highest net protein utilization was noted in animal groups fed the diet containing protein from raw fish. Protein assimilability from fish preserves was on the average 15% lower than that from raw fish.

  11. Kakskümmend kaks kala eesti rahvausundis. I

    Directory of Open Access Journals (Sweden)

    Mall Hiiemäe

    1999-01-01

    Full Text Available The present article is a sequel to the series of articles about the birds and insects in the Estonian fauna (See Hiiemäe 1996, 1997, 1998. In folk tradition the utilitarian attitude towards the fish was much more prevalent than towards the birds or insects. Until today, fishing has been an important source of living for the population in coastal regions, and for centuries the Estonians have shared their fishing waters with the neighbouring peoples: the Latvians, the Livonians, the Swedes, the Finnish and the Russians. Teutonic supremacy established its fishing rights both on the coasts and inland waters already in the 13th century.As to the subject of fish, Estonian folklore is rich in fishing magic. The disappearance of fish in a certain fishing area was often explained by the conflict between the locals and foreigners, or the leaving or taking the fish by some supernatural means (cf. the Estonian proverb: Envy draws the fish from sea.The bulk of folk tradition introduces generalisations based on long-term observation of nature and experience, also different prophesies and methods of magic to secure fishing luck. A part of the information centres on the aetiology of the fish, focusing on fabulates of uncertain genre about fish with distinctive outward characteristics, unique figure and behaviour. A separately standing group is formed of narratives which originate in the hunter-gatherer culture and have gone through changes influenced by land-tilling culture and Christianity, which regards fish as (somewhat demonised spiritual creatures of the sea world.European perch (Perca fluviatilis is distinguished by its habitat, spawning time and colour. The bright colour of its fins predicts the coming of cold winter. The fall in the number of perch has also been associated with the threat of Latvian fishermen to «take away» the perch if the fishermen were forced to pay for the fishing permits.Eel (Anguilla anguilla is believed to have developed from

  12. Fish Ontology framework for taxonomy-based fish recognition

    Science.gov (United States)

    Ali, Najib M.; Khan, Haris A.; Then, Amy Y-Hui; Ving Ching, Chong; Gaur, Manas

    2017-01-01

    Life science ontologies play an important role in Semantic Web. Given the diversity in fish species and the associated wealth of information, it is imperative to develop an ontology capable of linking and integrating this information in an automated fashion. As such, we introduce the Fish Ontology (FO), an automated classification architecture of existing fish taxa which provides taxonomic information on unknown fish based on metadata restrictions. It is designed to support knowledge discovery, provide semantic annotation of fish and fisheries resources, data integration, and information retrieval. Automated classification for unknown specimens is a unique feature that currently does not appear to exist in other known ontologies. Examples of automated classification for major groups of fish are demonstrated, showing the inferred information by introducing several restrictions at the species or specimen level. The current version of FO has 1,830 classes, includes widely used fisheries terminology, and models major aspects of fish taxonomy, grouping, and character. With more than 30,000 known fish species globally, the FO will be an indispensable tool for fish scientists and other interested users. PMID:28929028

  13. Archaeological Fish Bones Online: a digital archive of Sydney fishes

    Directory of Open Access Journals (Sweden)

    Sarah Colley

    2010-12-01

    Full Text Available The article presents the Archaeological Fish Bone Images sustainable digital archive and XTF-based image search and presentation tools developed with University of Sydney Library. The archive contains over 500 images of modern and archaeological fish remains and was developed as part of an archaeological research project into colonial and traditional Aboriginal fishing practices in Sydney, New South Wales, Australia from c.3000 years ago to the late 19th century. Links are provided to research information about fish ecology and fishing, the cultural and historical significance of fish taxa and details of taxonomic and anatomical nomenclature. Archaeological fish-bone images at the University of Sydney The article explains how and why the archive was developed, and identifies and discusses the research implications of significant gaps in current fish reference collections. Archive content is useful to researchers who need to identify and interpret fish remains of the same or similar biological taxa from Sydney or elsewhere. The design of the archive and online tools is relevant to other applications that use digital images to aid identification and interpretation of archaeological and other collections.

  14. SWALLOWED FISH BONES IN MALI

    Directory of Open Access Journals (Sweden)

    Sacko HB

    2015-07-01

    Full Text Available Objective: To study the different aspects, clinical, diagnostic and therapeutic of 114 cases of fish bones in the upper digestive tract . Methods: One hundred fourteen patients with fish bones suspected in the upper digestive tract were admitted in our department between February 2010 and October 2012. Results: There was a predominance of the male: 66 men (58%. The average age of the patients was 26 years with extremes 3 to 62 years old. The tongue base and vallecula are constituted the principals locations 66.66%. In the majority of the cases the fish bones were removed by direct pharyngoscopy in 43.86 %. We have not notified any serious complications. Conclusion: Therefore this study shows the foreign fish bones are frequently just as well in children as adult. The fish bones are particularly lodged in tongue base. The classical methods of extraction are permit to remove the all foreign fish bones.

  15. 75 FR 6058 - Federal Sport Fish Restoration; California Department of Fish and Game Fish Hatchery and Stocking...

    Science.gov (United States)

    2010-02-05

    ... Fish and Wildlife Service Federal Sport Fish Restoration; California Department of Fish and Game Fish.... Under the Sport Fish Restoration Act (SFRA), FWS proposes to fund actions associated with the operation...: Under the SFRA (Pub. L. 106-408), FWS has authority to grant Federal funds from the Sport...

  16. FishFrame

    DEFF Research Database (Denmark)

    Degel, Henrik; Jansen, Teunis

    2006-01-01

    for fixed reoccurring tasks like assessment working groups, data are often late and the quality can be unsatisfactory. The current situation of this “semi-manual distributed datawarehouse” can be improved technically. Methods for quality control, raising and calculation can be discussed and unified....... Development and test of software modules can be done once and reused by all. The biggest challenge in this is not technical – it is in organisation, coordination and trust. This challenge has been addressed by FishFrame - a web-based datawarehouse application. The “bottom-up” approach with maximum involvement...

  17. Gonadal development in fish.

    Science.gov (United States)

    Nishimura, Toshiya; Tanaka, Minoru

    2014-01-01

    Vertebrate reproduction depends on the function of 2 distinct gametes, sperm and eggs, which develop in 2 different organs, the testis and the ovary. Testes and ovaries are composed of germ cells, supporting cells and interstitial cells. In this review, we describe the origin and the fate of these cell lineages and how they interact with each other to form sexually dimorphic reproductive organs in medaka. We delineate how the temporally different association and establishment of these lineages contribute to a variety of seemingly different sex differentiation processes among teleost fish. Thus, teleosts represent an intriguing group in which to study the fundamental processes of gonadal development through comparing conserved and unique mechanisms.

  18. Fish intelligence, sentience and ethics.

    Science.gov (United States)

    Brown, Culum

    2015-01-01

    Fish are one of the most highly utilised vertebrate taxa by humans; they are harvested from wild stocks as part of global fishing industries, grown under intensive aquaculture conditions, are the most common pet and are widely used for scientific research. But fish are seldom afforded the same level of compassion or welfare as warm-blooded vertebrates. Part of the problem is the large gap between people's perception of fish intelligence and the scientific reality. This is an important issue because public perception guides government policy. The perception of an animal's intelligence often drives our decision whether or not to include them in our moral circle. From a welfare perspective, most researchers would suggest that if an animal is sentient, then it can most likely suffer and should therefore be offered some form of formal protection. There has been a debate about fish welfare for decades which centres on the question of whether they are sentient or conscious. The implications for affording the same level of protection to fish as other vertebrates are great, not least because of fishing-related industries. Here, I review the current state of knowledge of fish cognition starting with their sensory perception and moving on to cognition. The review reveals that fish perception and cognitive abilities often match or exceed other vertebrates. A review of the evidence for pain perception strongly suggests that fish experience pain in a manner similar to the rest of the vertebrates. Although scientists cannot provide a definitive answer on the level of consciousness for any non-human vertebrate, the extensive evidence of fish behavioural and cognitive sophistication and pain perception suggests that best practice would be to lend fish the same level of protection as any other vertebrate.

  19. BIOTECHNOLOGY OF THE FISH AQUACULTURE

    OpenAIRE

    L. P. Buchatsky

    2013-01-01

    The latest progress in biotechnology on fish aquaculture and different modern methods of investigations for increasing of fish productivity in aquaculture are analyzed. Except for the applied aspect, the use of modern biotechnological methods of investigations opens new possibilities for fundamental researches of sex-determining mechanisms, polyploidy, distant hybridization, and developmental biology of bony fishes. Review contains examples of utilizing modern biotechnology methods to obtain ...

  20. Tendency in fishing development and fish consumption in Serbia

    Directory of Open Access Journals (Sweden)

    Tešić Milan

    2013-01-01

    Full Text Available Production and catch of fish in Serbia increases from year to year, while in the world it reached its peak at the beginning of this century. Serbia has all the favorable natural and economic conditions for further development of fishing. Out of total production, that is, annual fish catch in Serbia, the greatest part is sold by organized purchase, lower part is exported, and the reminder goes to the market through retail. It is well known that food consumption, therefore fish consumption, depends on several factors such as the production level, retail price, consumers purchasing power and their eating habits. Therefore, when analyzing the tendency of production and consumption of fish in Serbia, it is important to investigate the influence of production, price and purchasing power of consumers on it. In order to investigate the set objective, there were used corresponding quantitative data obtained by Statistical Office of the Republic of Serbia. On the basis of the original data, there were determined certain parameters, which were used as variables for calculation of correlational-regressive and maginal analysis for determining the elasticity of demand and consummation of fish per capita in Serbia. Production and catch of fish in Serbia tended to increase during the observed period, with annual growth rate of 17.4%. Beside the fact that annual growth rate is 4.8%, fish consumption per capita in Serbia is still quite small (X=4.89kg, what is a consequence of population habit to consume predominantly meat. In our study we have found out that fish consumption in Serbia mostly depend on fish production per capita (rxy=0.6364, as well as on groos (rxy=0.6045 and net (rxy=0.5969 earnings. Also, it is determined that consumption elasticity has the highest growth in regard to fish production per capita. [Projekat Ministarstva nauke Republike Srbije, br. TR 31011

  1. 50 CFR 300.129 - Fishing year.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Fishing year. 300.129 Section 300.129 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS Vessels of the United States Fishing in Colombian Treaty Waters § 300.129 Fishing year. The fishing year...

  2. Sautéed Fish Slices

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Ingredients: A fresh fish, cooking oil, scallion, ginger, egg white, salt, MSG, cooking wine, cornstarch. Directions: 1. Clean and scale the fish and take out the internal organs. 2. Fillet the fish. Slice the fish into thin pieces. Coat the fish

  3. Fish Karyome: A karyological information network database of Indian Fishes.

    Science.gov (United States)

    Nagpure, Naresh Sahebrao; Pathak, Ajey Kumar; Pati, Rameshwar; Singh, Shri Prakash; Singh, Mahender; Sarkar, Uttam Kumar; Kushwaha, Basdeo; Kumar, Ravindra

    2012-01-01

    'Fish Karyome', a database on karyological information of Indian fishes have been developed that serves as central source for karyotype data about Indian fishes compiled from the published literature. Fish Karyome has been intended to serve as a liaison tool for the researchers and contains karyological information about 171 out of 2438 finfish species reported in India and is publically available via World Wide Web. The database provides information on chromosome number, morphology, sex chromosomes, karyotype formula and cytogenetic markers etc. Additionally, it also provides the phenotypic information that includes species name, its classification, and locality of sample collection, common name, local name, sex, geographical distribution, and IUCN Red list status. Besides, fish and karyotype images, references for 171 finfish species have been included in the database. Fish Karyome has been developed using SQL Server 2008, a relational database management system, Microsoft's ASP.NET-2008 and Macromedia's FLASH Technology under Windows 7 operating environment. The system also enables users to input new information and images into the database, search and view the information and images of interest using various search options. Fish Karyome has wide range of applications in species characterization and identification, sex determination, chromosomal mapping, karyo-evolution and systematics of fishes.

  4. Fish oil quality of by-product (fish skin from swangi fish

    Directory of Open Access Journals (Sweden)

    La Ode Huli

    2015-01-01

    Full Text Available The skin of swangi fish is a potential fish skin to be produced for fish oil. The objectives of this research were aimed to determine the yield and the best quality of fish oil and also to compare fatty acid profile of the fish according to different extraction methods. Fish oil extractions were used by wet rendering method with extraction temperatures of 60, 70, 80, 90, 100°C for 20, 30, and 40 minutes. Fish oil quality was determined by the chemical oil characteristics i.e. PV, FFA, AV, anisidin, and TOTOX. Fatty acid profile was analyzed using gas chromatography (Shimadzu. The results of the study showed that the highest fish oil yield in each treatment was obtained extraction temperature of 60°C for 30 minutes with percentage of 0.33, (70°C for 30 minutes 0.46, (80°C for 30 minutes 1.23, (90°C for 20 minutes 1.14 and (100°C for 20 minutes 0.84. These values were lower compare to Bligh & Dyer and Soxhlet methods. Then, the best fish oil quality was resulted on temperature extraction of 60°C for 30 minutes with PV, FFA, anisidin, AV, and TOTOX were 9.17 meq/kg, 6.92%, 13,77 mg KOH/g, 0.86 meq/kg and 19.19 meq/kg, respectively. FUFA fatty acid compositions of swangi skin fish oil especially EPA and DHA in wet rendering method were gained 0.73% and 2.53%, respectively. These results were lower than Bligh & Dyer method which was consisted of 3.66% (EPA, and 13.29% (DHA and also Soxhlet extraction method with value of EPA was 2.78% and DHA was 9.62%.Keywords: EPA, extraction temperature, DHA, fish oil quality, fish skin

  5. Fishes and humankind III. Editorial.

    Directory of Open Access Journals (Sweden)

    Andrew K. G. Jones

    1999-12-01

    Full Text Available The publication of this group of three papers form part of the 1987 meeting of the International Council for Archaeozoologists Fish Remains Working Group which took place at the University of York, U. K. The papers illustrate an increased awareness of the significance of ichthyological research to archaeology and cover three areas of research: taphonomy; fishing artefacts; and fish remains recovered from an excavation. Jones sheds some light on the relative robustness of the bewildering array of elements in a fish skeleton by recording damage to a skeleton when it is trampled. His paper suggests an index of robustness which might be used to assess the degree of fragmentation in archaeological assemblages. Kemp reports on the excavation of a small medieval building located adjacent to medieval fish ponds created by Cistercian monks in North Yorkshire, England. In addition to the structural evidence, an impressive assemblage of weights, presumably net weights, found on or near the site is published. Perhaps most significant is a large lead weight which may have been used to weight catches of fish from the ponds. Fish remains recovered from two excavations at the quayside at Newcastle-upon-Tyne, England are discussed by Nicholson. Around 6000 identified bones form the basis for the study, the majority of which were identified as Gadid (cod family or herring. While the main food fishes typify fish bone assemblages from most post-Roman urban archaeological sites, the identification of small fishes such as sandeels, smelt, gobies and buttefish may indicate the utilisation of fish not nowadays considered as food at all. Given the diversity of species (30 individual species identified it is suggested that the remains from the main bone-producing organic horizons, dated to the late twelfth to thirteenth centuries, may include discard from a nearby fishmarket.

  6. Fish ladders: safe fish passage or hotspot for predation?

    Directory of Open Access Journals (Sweden)

    Angelo Antonio Agostinho

    Full Text Available Fish ladders are a strategy for conserving biodiversity, as they can provide connectivity between fragmented habitats and reduce predation on shoals that accumulate immediately below dams. Although the impact of predation downstream of reservoirs has been investigated, especially in juvenile salmonids during their downstream movements, nothing is known about predation on Neotropical fish in the attraction and containment areas commonly found in translocation facilities. This study analysed predation in a fish passage system at the Lajeado Dam on the Tocantins River in Brazil. The abundance, distribution, and the permanence (time spent of large predatory fish along the ladder, the injuries imposed by piranhas during passage and the presence of other vertebrate predators were investigated. From December 2002 to October 2003, sampling was conducted in four regions (downstream, along the ladder, in the forebay, and upstream of the reservoir using gillnets, cast nets and counts or visual observations. The captured fish were tagged with thread and beads, and any mutilations were registered. Fish, birds and dolphins were the main predator groups observed, with a predominance of the first two groups. The entrance to the ladder, in the downstream region, was the area with the highest number of large predators and was the only region with relevant non-fish vertebrates. The main predatory fish species were Rhaphiodon vulpinus, Hydrolycus armatus, and Serrasalmus rhombeus. Tagged individuals were detected predating along the ladder for up to 90 days. Mutilations caused by Serrasalmus attacks were noted in 36% of species and 4% of individuals at the top of the ladder. Our results suggested that the high density of fish in the restricted ladder environment, which is associated with injuries suffered along the ladder course and the presence of multiple predator groups with different predation strategies, transformed the fish corridor into a hotspot for

  7. Ovarian steroidogenesis and the role of sex steroid hormones on ovarian growth and maturation of the Japanese eel.

    Science.gov (United States)

    Kazeto, Yukinori; Tosaka, Ryota; Matsubara, Hajime; Ijiri, Shigeho; Adachi, Shinji

    2011-11-01

    Three sex steroid hormones, estradiol-17β (E2), 11-ketotestosterone (11-KT), and 17α,20β-dihydroxy-4-pregnen-3-one (DHP), are well established as primary estrogen, androgen, and progestin, respectively, in teleost fish. Japanese eel, Anguilla japonica, would be a suitable candidate to study ovarian steroid physiology of fish because the ovarian growth and steroidogenesis is dormant under laboratory condition but can be induced by administration of exogenous gonadotropic reagents. In this review, we summarized our work on the function and production of sex steroid hormones in the ovary of the Japanese eel during ovarian growth and oocyte maturation artificially induced by treatment with extract of salmon pituitary. In vitro and in vivo assays suggest that 11-KT and E2 play primary roles in previtellogenic and vitellogenic growth of oocytes, respectively, whereas DHP is essential for induction of final oocyte maturation. We also reviewed the correlation between ovarian steroidogenesis to produce these sex steroid hormones, serum titers and gene expression.

  8. Speciation and host-parasite relationships in the parasite genus Gyrodactylus (Monogenea, Platyhelminthes) infecting gobies of the genus Pomatoschistus (Gobiidae, Teleostei).

    Science.gov (United States)

    Huyse, Tine; Audenaert, Vanessa; Volckaert, Filip A M

    2003-12-01

    Using species-level phylogenies, the speciation mode of Gyrodactylus species infecting a single host genus was evaluated. Eighteen Gyrodactylus species were collected from gobies of the genus Pomatoschistus and sympatric fish species across the distribution range of the hosts. The V4 region of the ssrRNA and the internal transcribed spacers encompassing the 5.8S rRNA gene were sequenced; by including published sequences a total of 30 species representing all subgenera were used in the data analyses. The molecular phylogeny did not support the morphological groupings into subgenera as based on the excretory system, suggesting that the genus needs systematic revisions. Paraphyly of the total Gyrodactylus fauna of the gobies indicates that at least two independent colonisation events were involved, giving rise to two separate groups, belonging to the subgenus Mesonephrotus and Paranephrotus, respectively. The most recent association probably originated from a host switching event from Gyrodactylus arcuatus, which parasitises three-spined stickleback, onto Pomatoschistus gobies. These species are highly host-specific and form a monophyletic group, two possible "signatures" of co-speciation. Host specificity was lower in the second group. The colonising capacity of these species is illustrated by a host jump from gobiids to another fish order (Anguilliformes), supporting the hypothesis of a European origin of Gyrodactylus anguillae and its intercontinental introduction by the eel trade. Thus, allopatric speciation seems to be the dominant mode of speciation in this host-parasite system, with a possible case of sympatric speciation.

  9. 76 FR 20707 - Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas County, WA

    Science.gov (United States)

    2011-04-13

    ... Bureau of Reclamation Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project; Kittitas... Environmental Impact Statement (FEIS) for the Cle Elum Dam Fish Passage Facilities and Fish Reintroduction... FEIS on the proposed Cle Elum Dam Fish Passage Facilities and Fish Reintroduction Project....

  10. Assessment demersal fish stocks Mauritania

    NARCIS (Netherlands)

    Corten, A.A.H.M.; Goudswaard, P.C.; Heessen, H.J.L.

    2006-01-01

    The RIVO project "Assessment of demersal fish stocks in Mauritania" was commissioned by the Ministry of Foreign Affairs of The Netherlands to produce information on the state of the demersal fish stocks (species that live near the bottom) in Mauritania, in particular octopus and shrimps. These stock

  11. Multisensor for fish quality determination

    DEFF Research Database (Denmark)

    Olafsdottir, G.; Nesvadba, P.; Di Natale, C.

    2004-01-01

    The European fish industry is still reluctant to implement methods other than sensory to monitor freshness and quality of fish products, although general concensus exists about the importance of various quality attributes and the need for methods to monitor quality. The objective of the project F...

  12. Sexual signals in electric fishes

    OpenAIRE

    Kramer, Bernd

    1990-01-01

    Electroreceptive bony fishes of Africa (the Mormyriformes) and South America (the Gymnotiformes) detect and communicate with conspecifics by their continuously discharging electric organs. Laboratory studies of members of each group are beginning to reveal the mechanisms of communicating with and finding mates, offering much scope for future studies of the behavioral ecology of electric fishes.

  13. Assessment demersal fish stocks Mauritania

    NARCIS (Netherlands)

    Corten, A.A.H.M.; Goudswaard, P.C.; Heessen, H.J.L.

    2006-01-01

    The RIVO project "Assessment of demersal fish stocks in Mauritania" was commissioned by the Ministry of Foreign Affairs of The Netherlands to produce information on the state of the demersal fish stocks (species that live near the bottom) in Mauritania, in particular octopus and shrimps. These stock

  14. Fish and Wildlife Mitigation Plan

    Science.gov (United States)

    1979-07-01

    NORTHERN CALIFORNIA COUNCIL OF FLY FISHING CLUBS Bob Baiocchi Vice President Conservation Chairman 1859 Salida Way Paradise, CA 95969 (916...PROJECT CALIFORNIA FIRST PHASE SPECIAL REPORT FISH AND WILDLIFE MITIGATION PLAN DEPARTMENT OF THE ARMY SACRAMENTO DISTRICT...CORPS OF ENGINEERS SACRAMENTO, CALIFORNIA 20081029163 DEFENSE TECHNICAL INFORMATION CENTER lufontuiioitfoir tktr Defense- CMtutucnity DTIC

  15. Ciguatera fish poisoning: a review

    NARCIS (Netherlands)

    Fouw JC de; Egmond HP van; Speijers GJA; CSR

    2001-01-01

    This review on ciguatera fish poisoning contains information on the ciguatera intoxication syndrome and the provoking ciguatoxins (CTXs) and gambiertoxin-4b (GTX-4B), of which CTX-1 is a major component at the end of food chain (the carnivore fish). Data on chemical structures and detection methods

  16. Biodiversity of arctic marine fishes

    DEFF Research Database (Denmark)

    Mecklenburg, Catherine W.; Møller, Peter Rask; Steinke, Dirk

    2011-01-01

    Taxonomic and distributional information on each fish species found in arctic marine waters is reviewed, and a list of families and species with commentary on distributional records is presented. The list incorporates results from examination of museum collections of arctic marine fishes dating b...

  17. Fish In Mutton Equals Delicious

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    CHINESE characters are pictographs. The character "delicious" consists of "fish" and "sheep." In fact, there are few recipes that uses fish and mutton as main ingredients, Yet, there is one dish called "fisn in mutton" whose taste is good enough to make people understand the connotation of

  18. Commercial Passenger Fishing Vessel Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the logbook data from U.S.A. Commercial Passenger Fishing Vessels (CPFV) fishing in the U.S.A. EEZ and in waters off of Baja California, from...

  19. Fish Springs pond snail : Refuge communication scenario

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Communication scenario between the branch of Listing and Recovery, Fish and Wildlife Enhancement, and Fish Springs National Wildlife Refuge (NWR), in regards to the...

  20. Fish Management Plan : Muscatatuck National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is the Fish Management Plan for Muscatatuck NWR. The Plan provides an introduction to the Refuge, a description of the area, a description of the fish resource...

  1. Neosho National Fish Hatchery contaminants survey results

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Fish were collected from Neosho National Fish Hatchery (NNFH) to determine if metal or organic contaminants were elevated in the biota located on the hatchery. Whole...

  2. Chautauqua National Wildlife Refuge : Sport Fishing Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Chautauqua National Wildlife Refuge Sport Fishing Plans covers the assesment and managment strategies for sport fishing in the Refuge. Focus is on bass, crappie,...

  3. US Fish and Wildlife Service Regional Boundaries

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Boundaries of the management Regions of the U.S. Fish and Wildlife Service. The U.S. Fish and Wildlife Service is organized into 8 geographic Regions.

  4. Do Fish Enhance Tank Mixing?

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Laursen, Jesper; Craig, Steven R.

    2005-01-01

    The design of fish rearing tanks represents a critical stage in the development of optimal aquaculture systems, especially in the context of recirculating systems. Poor hydrodynamics can compromise water quality, waste management and the physiology and behaviour of fish, and thence, production...... potential and operational profitability. The hydrodynamic performance of tanks, therefore, represents an important parameter during the tank design process. Because there are significant complexities in combining the rigid principles of hydrodynamics with the stochastic behaviour of fish, however, most data...... upon tank hydrokinetics has been derived using tanks void of fish. Clearly, the presence of randomly moving objects, such as fish, in a water column will influence not only tank volumes by displacing water, but due to their activity, water dynamics and associated in-tank processes. In order...

  5. Sex Determination Mechanisms in Fish

    Institute of Scientific and Technical Information of China (English)

    ZHANG Quanqi; SUN Xiaohua; QI Jie; WANG Zhigang; WANG Xinglian; WANG Xubo; ZHAI Teng

    2009-01-01

    In fish, sex determination (SD) system shows high variation. The SD mechanisms include environmental and genetic regulation. The research on SD system and related genes in intensively studied fish species was reviewed. Although some genes have been described as sex-related, only DMRTlbY can be considered as a master sex determination gene and none of them has been util-ized in aquaculture. The variation of fish SD system, the importance of sex-related genes in evolution research and the relations be-tween environmental factors and sex-related genes were also discussed. The fish sex determination mechanism remains largely un-known. Further research needs to be done considering the significance of fish SD studies in basic and applied aspects.

  6. Reproduction of European eel jeopardised by high levels of dioxins and dioxin-like PCBs?

    Science.gov (United States)

    Geeraerts, C; Focant, J-F; Eppe, G; De Pauw, E; Belpaire, C

    2011-09-01

    Dioxins, furans and dioxin-like polychlorinated biphenyls (PCBs) were analysed in muscle tissue from yellow phased European eel (Anguilla anguilla) from 38 sites in Belgium. Dioxin concentrations in eel vary considerably between sampling locations, indicating that yellow eel is a good indicator of local pollution levels. Measured levels of dioxin-like PCBs are much higher than those of the dioxins and furans. In the majority of the sites, eel has levels considered to be detrimental for their reproduction. Field levels of dioxin and dioxin-like PCBs are therefore suggested as an additional causal factor contributing to the decline of the European eel. 42% of the sampling sites show especially dioxin-like PCB levels exceeding the European consumption level (with a factor 3 on average). Human consumption of eel, especially in these highly contaminated sites, seems unjustified. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Length-weight and length-length relationships of seven loach species (Teleostei: Cypriniformes from five localities in northern Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Ashwini Keskar

    2015-12-01

    Full Text Available Length-weight (LWR and length-length (LLR relationships of seven loach species (Teleostei: Cypriniformes: Botia striata, Lepidocephalichthys thermalis, Paracanthocobitis mooreh, Indoreonectes evezardi, Nemacheilus anguilla, Nemachilichthys rueppelli and Schistura denisoni were studied from five localities within the Krishna River system of the Indian Western Ghats: Lonawala (Indrayani River, Paud (Mula River, Warje (Mutha River, Bhor (Nira River and Patan (Koyna River.  With the exception of L. thermalis all species are endemic to peninsular India, and to our knowledge this is the first presentation of LWR and LLR data for them.  New maximum lengths are also reported for I. evezardi, N. anguilla, N. rueppelli and S. denisoni. 

  8. First evidence of European eels exiting the Mediterranean Sea during their spawning migration

    DEFF Research Database (Denmark)

    Amilhat, Elsa; Aarestrup, Kim; Faliex, Elisabeth

    2016-01-01

    The migration route and the spawning site of the European eel Anguilla anguilla are still uncertain. It has been suggested that the Mediterranean eel stock does not contribute to spawning because there is no evidence of eels leaving the Mediterranean Sea. To test this hypothesis, we equipped eight...... female silver eels from the south of France with pop-up satellite tags during escapement from coastal waters. Once in deeper water, the eels quickly established diel vertical migration (DVM) between the upper and lower mesopelagic zone. Five tagged eels were taken by predators within the Mediterranean...... to show that eels from Mediterranean can cross the Strait of Gibraltar and continue their migration into the Atlantic Ocean. This finding suggests that Mediterranean countries, as for other EU states, have an important role to play in contributing to conservation efforts for the recovery of the European...

  9. GILL-ROT DISEASE OF EUROPEAN EEL INFECTED BY PSEUDOMONAS SP.%Pseudomonas sp. 引起欧洲鳗鲡烂鳃病的初步研究

    Institute of Scientific and Technical Information of China (English)

    樊海平; 曾占壮; 余培建; 李志青

    2001-01-01

    @@欧洲鳗鲡[Anguilla anguilla(L.)] 养殖过程中,细菌性疾病危害严重,其中烂鳃病周年发生且发病率高。欧洲鳗烂鳃病常与寄生虫病、真菌病并发,因而给治疗带来了困难。鳗鲡烂鳃病病原主要有柱状屈桡杆菌、噬纤维菌等[1—3]。本文报告由Pseudomonas sp. 引起的欧洲鳗鲡烂鳃病。

  10. Airborne laser fish finder

    Science.gov (United States)

    Zhu, Xiao; Li, Zaiguang; Huang, Houzheng

    1998-05-01

    An experimental airborne laser fish finder has been developed and field trial has been conducted. The Q-switched and frequency-doubled Nd:YAG laser output is of 100 HZ pulse repetition rate, 2 MW peak power, 8 ns pulse width. The green light receiving telescope is transmissive with 1400 mm focal length and 200 mm aperture. The varying-gain control of PMT and logarithmic amplifier are used to compress the 105 dynamic range of received signals. The main features of data real-time processing subsystem are of 200 Ms/s sampling rate, 8 bit resolution, adjacent average treatment of return waveforms with high noise, and pseudo-color display of water depth.

  11. Adult Neurogenesis in Fish.

    Science.gov (United States)

    Ganz, Julia; Brand, Michael

    2016-07-01

    Teleost fish have a remarkable neurogenic and regenerative capacity in the adult throughout the rostrocaudal axis of the brain. The distribution of proliferation zones shows a remarkable conservation, even in distantly related teleost species, suggesting a common teleost ground plan of proliferation zones. There are different progenitor populations in the neurogenic niches-progenitors positive for radial glial markers (dorsal telencephalon, hypothalamus) and progenitors with neuroepithelial-like characteristics (ventral telencephalon, optic tectum, cerebellum). Definition of these progenitors has allowed studying their role in normal growth of the adult brain, but also when challenged following a lesion. From these studies, important roles have emerged for intrinsic mechanisms and extrinsic signals controlling the activation of adult neurogenesis that enable regeneration of the adult brain to occur, opening up new perspectives on rekindling regeneration also in the context of the mammalian brain.

  12. Active Fish Tracking Sonar (AFTS) for Assessing Fish Behavior

    Energy Technology Data Exchange (ETDEWEB)

    Hedgepeth, J (Tenera Environmental, LLC); Johnson, Gary E.(BATTELLE (PACIFIC NW LAB)); Skalski, John R.; Burczynski, J (BioSonics Inc.)

    2002-11-01

    Active fish tracking sonars (AFTS) were used in 2001 to study fish movement in response to intake occlusion plates at The Dalles Dam on the Columbia River. AFTS provides three-dimensional fish tracks by aligning the axis of a split-beam transducer with a fish target. High-speed stepper motors move the transducer so that a tracked target remains on-axis. Occlusion plates with lateral extensions covered the top half of the turbine intakes to produce a fish friendly near-dam environment. Two AFTS were positioned at the center of Main Unit 1, one each for monitoring installed and removed plate conditions. A regression analysis showed that occlusion plates had pronounced effects on fish movement along the dam. The plates appeared to inhibit movement toward the spillway, movement toward the dam (especially in front of the turbine intake), and movement downward toward the turbines. Fish fate (as opposed to movement directions from regression slopes) into particular areas was determined using Markov-chain analysis. The sluiceway (a safer passage route above the turbine intake) zone of influence was larger with the occlusion plates installed, contrary to the regression results. In addition, the probability of passage out the near turbine and bottom sides of the sample volume was about 50% lower with occlusion plates installed.

  13. Fisheries and aquatic resources--fish health

    Science.gov (United States)

    Panek, Frank

    2008-01-01

    Fish health research at Leetown had its origin in the 1930’s when the Leetown Fish Hatchery and Experiment Station was constructed. In 1978, the National Fish Health Research Laboratory, now a component of the Leetown Science Center, was established to solve emerging and known disease problems affecting fish and other aquatic organisms critical to species restoration programs. Center scientists develop methods for the isolation, detection, and identification of fish pathogens and for prevention and control of fish diseases.

  14. Fish and Soup of Hubei Cuisine

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    I was very impressed by the delicious freshwater fish dish from the well-known Changjiang River and Dongting Lake, the first time I travelled to Hubei Province. Hubei is famous for its freshwater fish dishes since it has so many lakes. The steamed Wuchang fish is one. Wuchang fish is pure, tender and fat and is considered a first-class freshwater fish. Waiters in local restaurants usually bring the fresh Wuchang fish to the

  15. Tropical fishes dominate temperate reef fish communities within western Japan.

    Science.gov (United States)

    Nakamura, Yohei; Feary, David A; Kanda, Masaru; Yamaoka, Kosaku

    2013-01-01

    Climate change is resulting in rapid poleward shifts in the geographical distribution of tropical and subtropical fish species. We can expect that such range shifts are likely to be limited by species-specific resource requirements, with temperate rocky reefs potentially lacking a range of settlement substrates or specific dietary components important in structuring the settlement and success of tropical and subtropical fish species. We examined the importance of resource use in structuring the distribution patterns of range shifting tropical and subtropical fishes, comparing this with resident temperate fish species within western Japan (Tosa Bay); the abundance, diversity, size class, functional structure and latitudinal range of reef fishes utilizing both coral reef and adjacent rocky reef habitat were quantified over a 2 year period (2008-2010). This region has undergone rapid poleward expansion of reef-building corals in response to increasing coastal water temperatures, and forms one of the global hotspots for rapid coastal changes. Despite the temperate latitude surveyed (33°N, 133°E) the fish assemblage was both numerically, and in terms of richness, dominated by tropical fishes. Such tropical faunal dominance was apparent within both coral, and rocky reef habitats. The size structure of the assemblage suggested that a relatively large number of tropical species are overwintering within both coral and rocky habitats, with a subset of these species being potentially reproductively active. The relatively high abundance and richness of tropical species with obligate associations with live coral resources (i.e., obligate corallivores) shows that this region holds the most well developed temperate-located tropical fish fauna globally. We argue that future tropicalisation of the fish fauna in western Japan, associated with increasing coral habitat development and reported increasing shifts in coastal water temperatures, may have considerable positive economic

  16. Tropical fishes dominate temperate reef fish communities within western Japan.

    Directory of Open Access Journals (Sweden)

    Yohei Nakamura

    Full Text Available Climate change is resulting in rapid poleward shifts in the geographical distribution of tropical and subtropical fish species. We can expect that such range shifts are likely to be limited by species-specific resource requirements, with temperate rocky reefs potentially lacking a range of settlement substrates or specific dietary components important in structuring the settlement and success of tropical and subtropical fish species. We examined the importance of resource use in structuring the distribution patterns of range shifting tropical and subtropical fishes, comparing this with resident temperate fish species within western Japan (Tosa Bay; the abundance, diversity, size class, functional structure and latitudinal range of reef fishes utilizing both coral reef and adjacent rocky reef habitat were quantified over a 2 year period (2008-2010. This region has undergone rapid poleward expansion of reef-building corals in response to increasing coastal water temperatures, and forms one of the global hotspots for rapid coastal changes. Despite the temperate latitude surveyed (33°N, 133°E the fish assemblage was both numerically, and in terms of richness, dominated by tropical fishes. Such tropical faunal dominance was apparent within both coral, and rocky reef habitats. The size structure of the assemblage suggested that a relatively large number of tropical species are overwintering within both coral and rocky habitats, with a subset of these species being potentially reproductively active. The relatively high abundance and richness of tropical species with obligate associations with live coral resources (i.e., obligate corallivores shows that this region holds the most well developed temperate-located tropical fish fauna globally. We argue that future tropicalisation of the fish fauna in western Japan, associated with increasing coral habitat development and reported increasing shifts in coastal water temperatures, may have considerable

  17. The Fresh-water Fishes of Singapore

    NARCIS (Netherlands)

    Alfred, E.R.

    1966-01-01

    CONTENTS Page Introduction 5 Materials................... 6 The environment................. 7 Ichthyological literature of Singapore........... 9 Aquarium fishes................. io Pond culture fishes................ n Introduced species................. 12 Acknowledgements................ 13 Syst

  18. Ecology of North Sea fish

    Science.gov (United States)

    Daan, N.; Bromley, P. J.; Hislop, J. R. G.; Nielsen, N. A.

    Fishes of the North Sea include over 200 species exhibiting widely differing ecological characteristics. There is a wealth of literature and, in this paper, we have restricted ourselves to providing generalized data on the more abundant species, with a view of highlighting those aspects which link the total fish community to the biotic and abiotic environment. There is necessarily a bias towards commercial species, because most of the pertinent information is related specifically to fish which are heavily fished. However, since there are few abundant species which are not exploited, the ecological links of the total fish community to other components of the system are well represented by the selection. Moreover, exploitation of the fish community may have indirectly affected the ecological relationships in the entire system. It follows that an understandinf of the impact of fisheries on the fish community is likely to play a key role in helping us to understand how the North Sea ecosystem functions. The paper highlights various ecological aspects of the fish fauna including population dynamics, spawning in time and space, distribution, variations in year class strength, feeding, density-dependent growth and changes in species composition. Despite long time series of quantitative biological information for individual species and the obvious impact of fisheries on longevity and productivity of the fish community, the general conclusion is that it remains very difficult to separate effects of fisheries and of the environment on reproductive success, in which the variation is the most important destabilizing factor in the regulation of exploited fish populations. Another conclusion is that the spatial heterogeneity of the fish community in the North Sea is a factor of considerable concern in trying to link fish production to other components. It would seem likely that, to improve our understanding of the ecological linkages in the entire system, the spatial differences

  19. Zinc is an essential trace element for spermatogenesis

    OpenAIRE

    Yamaguchi, Sonoko; Miura, Chiemi; Kikuchi, Kazuya; Fritzie T Celino; Agusa, Tetsuro; Tanabe, Shinsuke; Miura, Takeshi

    2009-01-01

    Zinc (Zn) plays important roles in various biological activities but there is little available information regarding its functions in spermatogenesis. In our current study, we further examined the role of Zn during spermatogenesis in the Japanese eel (Anguilla japonica). Human CG (hCG) was injected into the animals to induce spermatogenesis, after which the concentration of Zn in the testis increased in tandem with the progression of spermatogenesis. Staining of testicular cells with a Zn-spe...

  20. The Caribbean -- Implications for the US Army.

    Science.gov (United States)

    1982-04-16

    Greater Antilles while those smaller, north-south islands are called the Lesser Antilles. Of the Lesser Antilles, those from Anguilla to Guadeloupe are...Land that is not used for housing or agriculture would be called lush forestation-jungle to some. The Caribbean Sea is deep-the average depth runs...South America) and eventually agricultural opportuni- ties.3 The French, English, Portugese and Dutch saw the military and economic potential in