the phylogenetics of anguillicolidae (nematoda: anguillicoloidea), swimbladder parasites of eels.anguillicolidae yamaguti, 1935 is a family of parasitic nematode infecting fresh-water eels of the genus anguilla, comprising five species in the genera anguillicola and anguillicoloides. anguillicoloides crassus is of particular importance, as it has recently spread from its endemic range in the eastern pacific to europe and north america, where it poses a significant threat to new, naïve hosts such as the economic important eel species anguilla anguilla and anguilla rostrata. the anguillicolid ...201222559142
swim bladder nematodes (anguillicoloides crassus) disturb silvering in european eels (anguilla anguilla).the introduced parasite anguillicoloides crassus is thought to play an important role in the decline of freshwater eel (anguilla spp.) populations. these nematodes are known to negatively affect many fitness-related traits in eels. we used experimental infections to study the effect of a. crassus on the relative size or mass of organs, and the expression of functionally relevant genes (total of 12 parameters) that are involved in the silvering process of anguilla anguilla. our results showed tha ...201222404329
ultrastructure of the spermatozoon of bothriocephalus claviceps (cestoda, pseudophyllidea): a parasite of anguilla anguilla (fish, teleostei).the mature bothriocephalus claviceps spermatozoon is filiform and tapered at both extremities. it contains two axonemes of unequal lengths of the 9+"1" pattern of the trepaxonemata. the anterior extremity exhibits an apical cone of an electron-dense material about 6.6 microm long by 0.2 microm wide at its base and a crest-like body making an angle of about 40 degrees with the spermatozoon axis. it is spiralized around the whole extremity of the spermatozoon. the nucleus is a cord of electron-den ...200717235546
the concept of specificity in the procercoid-copepod system: bothriocephalus claviceps (cestoda) a parasite of the eel (anguilla anguilla).this paper describes experimental work on parasite specificity in the copepod-procercoid system of bothriocephalus claviceps. two criteria were used to characterize five potential host species macrocyclops albidus, macrocyclops fuscus, eucyclops serrulatus, acanthocyclops robustus and macrocyclops viridis viridis. the first criterion involves susceptibility of the copepods to infection. the results show random or aggregative distributions and variable susceptibilities according to the species. w ...19873575289
[experimental approach to the role of the paratenic host in the circulation of the parasite bothriocephalus claviceps goeze, 1782 (cestoda, pseudophyllidea)].this article concerns an experimental work monitored in 5 species of fishes in the order to evaluate their value of paratenic hosts, in the cycle of bothriocephalus claviceps, a parasite of the eel, anguilla anguilla. the intestinal localisation and the lack of development of parasites are the two principal characters of this parasitism. the second character is sometimes contradicted. the effective evolution has been observed during 20 days. the more important losses of parasites coincide with t ...19863813425
[evolutive cycle, in a single intermediate host, of bothriocephalus claviceps (goeze, 1782), cestode of anguilla anguilla l]. 200614220586
anguilla anguilla intestinal immune response to natural infection with contracaecum rudolphii a larvae.the european eel, anguilla anguilla, is a major warm-water fish species cultured in north and south europe. seventy-one a. anguilla collected between 2010 and 2015 from the comacchio lagoons were examined. fish were infected and damaged by larvae (l3) of the nematode contracaecum rudolphii a, which were encapsulated within the thickness of the intestinal wall and within the external visceral peritoneum (serosa). conspicuous granulomas, visible at sites of infection, were arranged in a trilayer, ...201626814373
the development of a loop-mediated isothermal amplification assay for rapid and sensitive detection of abalone herpesvirus dna.a loop-mediated isothermal amplification (lamp) assay was developed for the detection of abalone herpesvirus dna. two pairs of primers were designed, based on the sequence of the dna polymerase gene of abalone herpesvirus. the reaction temperature and time were optimized to 63°c and 60min, respectively. lamp amplicons were analyzed by 2% agarose gel electrophoresis or by visual inspection of a colour change emitted by fluorescent dye. the method developed was specific for the detection of abalon ...201424291740
koi herpesvirus encodes and expresses a functional interleukin-10.koi herpesvirus (khv) (species cyprinid herpesvirus 3) orf134 was shown to transcribe a spliced transcript encoding a 179-amino-acid (aa) interleukin-10 (il-10) homolog (khvil-10) in koi fin (kf-1) cells. pairwise sequence alignment indicated that the expressed product shares 25% identity with carp il-10, 22 to 24% identity with mammalian (including primate) il-10s, and 19.1% identity with european eel herpesvirus il-10 (ahvil-10). in phylogenetic analyses, khvil-10 fell in a divergent position ...201222896613
co-infection with pseudomonas anguilliseptica and delftia acidovorans in the european eel, anguilla anguilla (l.): a case history of an illegally trafficked protected species.inspections by customs agents at barcelona airport discovered 420 kg of contraband glass eels prepared for shipment to hong kong. after confiscation of these animals by police, they were transported to holding facilities to be maintained until after a judicial hearing. upon arrival, they were separated into two groups and held under ambient flow-through conditions in fresh water. during their captivity period, several peaks in mortality occurred and multiple bacterial strains were isolated from ...201323297744
cloning and expression analyses of interferon regulatory factor (irf) 3 and 7 genes in european eel, anguilla anguilla with the identification of genes involved in ifn production.interferon regulatory factor (irf) 3 and irf7 have been identified as regulators of type i interferon (ifn) gene expression in mammals. in the present study, the two genes were cloned and characterized in the european eel, anguilla anguilla. the full-length cdna sequence of irf3 and irf7 in the european eel, named as aairf3 and aairf7 consists of 2879 and 2419 bp respectively. multiple alignments showed that the two irfs have a highly conserved dna binding domain (dbd) in the n terminus, with th ...201424565894
ubiquitous distribution of fluorescent protein in muscles of four species and two subspecies of eel (genus anguilla).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 to the 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 fat ...201728360397
effect of the probiotic lactobacillus rhamnosus on the expression of genes involved in european eel spermatogenesis.positive effects of probiotics on fish reproduction have been reported in several species. in the present study, 40 male european eels were weekly treated with recombinant hcg for 9 weeks and with three different concentrations (10(3), 10(5), and 10(6) cfu/ml) of probiotic lactobacillus rhamnosus imc 501 (sinbyotec, italy). the probiotics were daily added to the water from the sixth week of the hcg treatment. males from the treated and control groups were sacrificed after 1, 2, and 3 weeks of pr ...201526271165
aleuria aurantia lectin exhibits antifungal activity against mucor racemosus.aleuria aurantia lectin (aal) is an l-fucose-specific lectin produced in the mycelia and fruit-bodies of the widespread ascomycete fungus aleuria aurantia. it is extensively used in the detection of fucose, but its physiological role remains unknown. to investigate this, we analyzed the interaction between aal and, a zygomycete fungus mucor racemosus, which is assumed to contain fucose in its cell wall. aal specifically bound to the hyphae of m. racemosus, because binding was inhibited by l-fuco ...201222738968
morphometric analysis of the hard parts of pseudodactylogyrus anguillae and pseudodactylogyrus bini (monogenea: dactylogyridae) on the gill apparatus of the european eels ( anguilla anguilla ) from the freshwaters of latvia.we investigated the spatial distribution and measured the hard parts of the attachment apparatuses and reproductive organs of the 2 eel-specific monogenean species pseudodactylogyrus anguillae and pseudodactylogyrus bini. comparative analysis focused on parasite microhabitats within the gill apparatus. additionally, we compared the morphometric characteristics of the monogeneans based on geographical locality and seasonality. the attachment apparatus and reproductive organ characteristics of the ...201626741978
divergence between asian, european and canadian populations of the monogenean pseudodactylogyrus bini indicated by ribosomal dna patterns.the monogenean pseudodactylogyrus bini parasitizes the gills of eels belonging to the genus anguilla. circumstantial evidence suggests that the parasite has been spread accidentally from the pacific area (east asia) to europe by the intercontinental eel trade. this is based on early descriptions of the parasites from asian regions and the lack of records of the parasites in europe before 1977. in addition, the susceptibility of european eels to infections with the parasite is significantly highe ...201020230654
characterization of pamp/prr interactions in european eel (anguilla anguilla) macrophage-like primary cell cultures.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 in ...201323911651
the effect of thawing methods on the quality of eels (anguilla anguilla).physical (colour), chemical (ph, total volatile basic nitrogen (tvb-n), thiobarbituric acid values (tba)) and microbiological (total aerobic mesophylic bacteria, salmonella, coliform, yeast and mould counts) analyses were carried out on thawed european eel (anguilla anguilla). different thawing treatments were used (in a refrigerator, in water, in air at ambient temperature and in a microwave oven). the results obtained were compared statistically with those of fresh fish. ph, tba and a(∗) value ...200826047438
an outbreak of shewanella putrefaciens group in wild eels anguilla anguilla l. favoured by hypoxic aquatic environments.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 ...201627982438
an enriched european eel transcriptome sheds light upon host-pathogen interactions with vibrio vulnificus.infectious diseases are one of the principal bottlenecks for the european eel recovery. the aim of this study was to develop a new molecular tool to be used in host-pathogen interaction experiments in the eel. to this end, we first stimulated adult eels with different pathogen-associated molecular patterns (pamps), extracted rna from the immune-related tissues and sequenced the transcriptome. we obtained more than 2 x 10(6) reads that were assembled and annotated into 45,067 new descriptions wit ...201526207370
early steps in the european eel (anguilla anguilla)-vibrio vulnificus interaction in the gills: role of the rtxa13 toxin.vibrio vulnificus is an aquatic gram-negative bacterium that causes a systemic disease in eels called warm-water vibriosis. natural disease occurs via water born infection; bacteria attach to the gills (the main portal of entry) and spread to the internal organs through the bloodstream, provoking host death by haemorrhagic septicaemia. v. vulnificus produces a toxin called rtxa13 that hypothetically interferes with the eel immune system facilitating bacterial invasion and subsequent death by sep ...201525613341
concentrations of microcystins in tissues of several fish species from freshwater reservoirs and ponds.the aim of this study is to summarise the determination of concentrations of microcystins (mcs) in muscle and liver of freshwater fish species caught in stagnant waters of the czech republic. within the years 2007-2009, 351 muscle samples and 291 liver samples of 16 freshwater fish species derived from four fishponds, and four water reservoirs were analysed. mcs were detected in 53 liver samples. the highest concentrations of microcystins were determined in liver samples of carnivorous fish spec ...201323756815
distribution and relationships of as, cd, pb and hg in freshwater fish from five french fishing areas.the concentrations of arsenic, cadmium, mercury and lead in 149 muscle samples of eight freshwater fish species (european eel, bream, common carp, european catfish, roach, perch, pike and pikeperch) from five different french fishing areas from contaminated and control sites were measured by inductively coupled plasma mass spectrometry after microwave digestion under pressure. no significant correlation was found between the condition factor (cf), based on the length-mass relationship, and as, c ...201323177713
metals in edible fish from vistula river and dead vistula river channel, baltic sea.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 ...201222428891
tgf-beta3 exists in bony fish.a partial nucleotide sequence of transforming growth factor-beta3 (tgf-beta3) has been isolated from the siberian sturgeon (acipenser baeri), rainbow trout (oncorhynchus mykiss) and european eel (anguilla anguilla), confirming a ubiquitous presence in the ray-finned (actinopterygian) bony fish. the bony fish tgf-beta3 is highly conserved, with some 83-84% nucleotide identity (coding region) and 90-95% predicted amino acid identity to known homeotherm tgf-beta3's. far lower homologies are apparen ...199910614492
the presence of eu priority substances mercury, hexachlorobenzene, hexachlorobutadiene and pbdes in wild fish from four english rivers.since 2007 about 200 to 300 fish per year--generally roach (rutilus rutilus) also a few bleak (alburnus alburnus) and eels (anguilla anguilla)--have been collected from a number of english river sites and stored at -80°c to build up a fish tissue archive as a resource for the monitoring of pollutants. some of the fish from the fish tissue archive from the years 2007-2011 were analyzed for substances in current and proposed european legislation regarding environmental quality standards (eqs) in b ...201323747559
angiotensin ii dependent cardiac remodeling in the eel anguilla anguilla involves the nos/no system.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 and localization of molecules which regulate cell growth. to deeper investigate the morpho-functional chronic influences of angii on the eel heart and the molecular mechanisms involved, freshwater eels ( ...201728232085
nuclear and membrane progestin receptors in the european eel: characterization and expression in vivo through spermatogenesis.characterization of all the progestin receptor genes (prs) found in the european eel has been performed. there were five membrane prs (mprs): mprα (alpha), mpral1 (alpha-like1), mpral2 (alpha-like2), mprγ (gamma), mprδ (delta) and two nuclear prs (nprs or pgrs): pgr1 and pgr2. in silico studies showed that the c and e(f) domains of pgr are well conserved among vertebrates whereas the a/b domain is not. phylogeny and synteny analyses suggest that eel duplicated pgr (pgr1 and pgr2) originated from ...201728196764
from eels to the importance of cancer biobanks. 201528031917
protective responses of intestinal mucous cells in a range of fish-helminth systems.histopathological, immunofluorescence and ultrastructural studies were conducted on the intestines of four fish species infected with different taxa of enteric helminths. brown trout (salmo trutta trutta), eel (anguilla anguilla) and tench (tinca tinca) obtained from lake piediluco (central italy) were examined. brown trout and eel were infected with two species of acanthocephalans, and tench was parasitized with a tapeworm species. in addition to the above site, specimens of chub (squalius ceph ...201628026022
bile metabolites of polycyclic aromatic hydrocarbons (pahs) in three species of fish from morocco.polycyclic aromatic hydrocarbons (pah) are environmental contaminants that pose significant risk to health of fish. environmental pollution of fish is a topic of rising attention in morocco. however, only few studies have been carried out so far, describing the potential threat of organic pollution to moroccan aquatic ecosystem. two polycyclic aromatic hydrocarbon (pah) metabolites, 1-hydroxypyrene (1-oh-pyr) and 1-hydroxyphenanthrene (1-oh-phen), were identified and quantified from the bile of ...201627867806
migratory behavior, metabolism, oxidative stress and mercury concentrations in marine and estuarine european glass eels (anguilla anguilla).the relationships between the migratory behavior, methylmercury (mehg) concentrations, oxidative stress response and detoxification processes were investigated in glass eels collected in marine (molliets) and estuarine (urt) waters (adour estuary, south west france) at the end of the fishing season (april). glass eel migratory behavior was investigated in an experimental flume according to their response to dusk. fish responding to the decrease in light intensity by ascending in the water column ...201727864042
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.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 ...201627834886
assessing pre- and post-zygotic barriers between north atlantic eels (anguilla anguilla and a. rostrata).elucidating barriers to gene flow is important for understanding the dynamics of speciation. here we investigate pre- and post-zygotic mechanisms acting between the two hybridizing species of atlantic eels: anguilla anguilla and a. rostrata. temporally varying hybridization was examined by analyzing 85 species-diagnostic single-nucleotide polymorphisms (snps; fst ⩾0.95) in eel larvae sampled in the spawning region in the sargasso sea in 2007 (n=92) and 2014 (n=460). we further investigated wheth ...201727827390
how the european eel (anguilla anguilla) loses its skeletal framework across lifetime.european eels (anguilla anguilla) undertake an impressive 5 000 km long migration from european fresh waters through the north atlantic ocean to the sargasso sea. along with sexual maturation, the eel skeleton undergoes a remarkable morphological transformation during migration, where a hitherto completely obscure bone loss phenomenon occurs. to unravel mechanisms of the maturation-related decay of the skeleton, we performed a multiscale assessment of eels' bones at different life-cycle stages. ...201627798301
evidence for high concentrations and maternal transfer of substituted diphenylamines in european eels analyzed by two-dimensional gas chromatography-time-of-flight mass spectrometry and gas chromatography-fourier transform ion cyclotron resonance mass spectrometry.chemical pollution is hypothesized to be one of the factors driving the strong decline of the critically endangered european eel population. specifically, the impact of contaminants on the quality of spawning eels and subsequent embryo survival and development has been discussed as crucial investigation point. however, so far, only very limited information on potential negative effects of contaminants on the reproduction of eels is available. through the combination of nontargeted ultrahigh-reso ...201627791360
role of potassium and ph on the initiation of sperm motility in the european eel.the role of potassium from the seminal plasma and/or the activation media was examined by selectively removing k(+) from this media, and by testing the use of k(+) channel inhibitors and a k-ionophore. sperm motility was measured using a casa system, intracellular k(+) and ph were measured by flow cytometry, and sperm head area was measured by asma: automated sperm morphometry analyses. sperm motility was notably inhibited by the removal of k(+) from the seminal plasma and by treatment with the ...201727693817
the expression of nuclear and membrane estrogen receptors in the european eel throughout spermatogenesis.estradiol (e2) can bind to nuclear estrogen receptors (esr) or membrane estrogen receptors (gper). while mammals possess two nuclear esrs and one membrane gper, the european eel, like most other teleosts, has three nuclear esrs and two membrane gpers, as the result of a teleost specific genome duplication. in the current study, the expression of the three nuclear esrs (esr1, esr2a and esr2b) and the two membrane gpers (gpera and gperb) in the brain-pituitary-gonad (bpg) axis of the european eel ...201727590411
silvering and swimming effects on aerobic metabolism and reactive oxygen species in the european eel.silvering, the last metamorphosis in the eel life cycle induces morphological and physiological modifications in yellow eels (sedentary stage). it pre-adapts them to cope with the extreme conditions they will encounter during their 6000-km spawning migration. a previous study showed that silver eels are able to cope with reactive oxygen species (ros) over-production linked to an increase in aerobic metabolism during sustained swimming, but the question remains as to whether this mechanism is ass ...201727717909
the chromogranin a-derived sympathomimetic serpinin depresses myocardial performance in teleost and amphibian hearts.chromogranin a (cga) is an acidic protein co-stored with catecholamines, hormones and neuropeptides in the secretory granules of endocrine, neuronal and other cell types (including cardiomyocytes). proteolytic cleavage in the c terminus of cga generates a 2.9kda peptide named serpinin (serp; ala26leu) that can be modified at its n terminus to form a pyroglutamate residue (pglu-serp). in the rat heart, both peptides increase contractility and relaxation through a β-adrenergic-like action mechanis ...201727633326
maximal oxygen consumption increases with temperature in the european eel (anguilla anguilla) through increased heart rate and arteriovenous 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 ...201627766150
evidences of dna and chromosomal damage induced by the mancozeb-based fungicide mancozan(®) in fish (anguilla anguilla l.).the formulation mancozan(®), containing mancozeb as active ingredient, is among the most widely used fungicides. although mancozeb has been detected in surface waters, studies addressing the genotoxic risk to fish arising from the use of this formulation, testing environmentally realistic concentrations, are absent from the literature. hence, this work aimed to investigate the dna and chromosome damaging potential of mancozan(®) (0.29 and 2.9μgl(-1)) in the european eel (anguilla anguilla l.), a ...201627742361
empirical observations of the spawning migration of european eels: the long and dangerous road to the sargasso sea.the spawning migration of the european eel (anguilla anguilla l.) to the sargasso sea is one of the greatest animal migrations. however, the duration and route of the migration remain uncertain. using fishery data from 20 rivers across europe, we show that most eels begin their oceanic migration between august and december. we used electronic tagging techniques to map the oceanic migration from eels released from four regions in europe. of 707 eels tagged, we received 206 data sets. many migrati ...201627713924
accumulation of persistent organic pollutants in consumers of eel from polluted rivers compared to marketable eel.globally, many river sediments are seriously contaminated with persistent organic pollutants (pops) known to accumulate in aquatic food. in the netherlands, toxicological risks of human exposure to dioxins and dioxin-like compounds led to a ban on eel fishing in the rhine-meuse delta. the aim of this study is to investigate differences in serum pop levels in consumers of eel from high-polluted areas and consumers of eel from low-polluted areas or aquaculture. in total 80 dutch men were included, ...201627697634
the european eel nccβ gene encodes a thiazide-resistant na-cl cotransporter.the thiazide-sensitive na-cl cotransporter (ncc) is the major pathway for salt reabsorption in the mammalian distal convoluted tubule. ncc plays a key role in the regulation of blood pressure. its inhibition with thiazides constitutes the primary baseline therapy for arterial hypertension. however, the thiazide-binding site in ncc is unknown. mammals have only one gene encoding for ncc. the eel, however, contains a duplicate gene. nccα is an ortholog of mammalian ncc and is expressed in the kidn ...201627587391
does asymmetric gene flow among matrilines maintain the evolutionary potential of the european eel?using evolutionary theory to predict the dynamics of populations is one of the aims of evolutionary conservation. in endangered species, with geographic range extending over continuous areas, the predictive capacity of evolutionary-based conservation measures greatly depends on the accurate identification of reproductive units. the endangered european eel (anguilla anguilla) is a highly migratory fish species with declining population due to a steep recruitment collapse in the beginning of the 1 ...201627551384
a comparison of techniques for studying oogenesis in the european eel anguilla anguilla.a multi-technique approach was used to study the changes occurring in european eel anguilla anguilla ovaries during hormonally-induced vitellogenesis. aside from classic techniques used to monitor the vitellogenic process, such as ovary histology, fat content analysis, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (sds-page) and vitellogenin enzyme linked immunosorbent assay (elisa), a new technique, fourier-transform infrared (ft-ir) microspectroscopy, was used to analyse a. anguil ...201627500665
functional characterisation of eel dopamine d2 receptors and involvement in the direct inhibition of pituitary various vertebrate species, dopamine (da) exerts an inhibitory action on reproduction. in the european eel, da plays a pivotal role in the inhibitory control of gonadotroph function and the blockade of puberty. in vivo studies have suggested that this effect is mediated by receptors pharmacologically related to the d2 family. in the european eel, two distinct d2 receptor (d2-r) paralogous genes have been identified (d2a-r and d2b-r) and both were shown to be expressed in the pituitary. we inv ...201627453551
phthalate metabolites in the european eel (anguilla anguilla) from mediterranean coastal lagoons.the levels and fate of phthalate metabolites have been poorly evaluated in fish, despite their potential ecotoxicological impacts. the present study aims to characterize the levels of phthalate metabolites in muscle tissue of yellow eels (anguilla anguilla) from two coastal mediterranean lagoons, during three sampling periods. nine phthalate metabolites were detected in >70% of the samples. slightly higher levels of phthalate metabolites were detected in march and june compared to october, sugge ...201627412480
a comparison of metal concentrations in the tissues of yellow american eel (anguilla rostrata) and european eel (anguilla anguilla).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 habit ...201627395077
accumulation of neurotoxic organochlorines and trace elements in brain of female european eel (anguilla anguilla).xenobiotics such as organochlorine compounds (ocs) and metals have been suggested to play a significant role in the collapse of european eel stocks in the last decades. several of these pollutants could affect functioning of the nervous system. still, no information is so far available on levels of potentially neurotoxic pollutants in eel brain. in present study, carried out on female eels caught in belgian rivers and canals, we analyzed brain levels of potentially-neurotoxic trace elements (ag, ...201627376663
methylmercury and total mercury in eels, anguilla anguilla, from lakes in northeastern poland: health risk the aquatic environment, mercury is readily methylated into its most toxic form of methylmercury. in this form, it enters the aquatic food chain and its concentrations increase in subsequent links, which decreases the quality of fish meat and poses risks to consumer health. concentrations of methylmercury (mehg) and total mercury (thg) were determined in the muscle tissues of 64 eel specimens measuring from 59 to 95 cm in length as functions of specimen size and weight. risks posed to consume ...201627357082
identification of the major proteins present in the seminal plasma of european eel, and how hormonal treatment affects their evolution. correlation with sperm quality. 201627343370
fipronil and two of its transformation products in water and european eel from the river elbe.fipronil is an insecticide which, based on its mode of action, is intended to be predominantly toxic towards insects. fipronil bioaccumulates and some of its transformation products were reported to be similar or even more stable in the environment and to show an enhanced toxicity against non-target organisms compared to the parent compound. the current study investigated the occurrence of fipronil and two of its transformation products, fipronil-desulfinyl and fipronil-sulfone, in water as well ...201627289396
interactive effects of dietary composition and hormonal treatment on reproductive development of cultured female european eel, anguilla anguilla.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 approximately 4.5 and 2.6 times higher compared to the other diet, respectively. after the feeding period, each diet group was divided into two and each half received one of two hormonal treatments using s ...201627264530
first production of larvae using cryopreserved sperm: effects of preservation temperature and cryopreservation on european eel sperm fertilization capacity.sperm cryopreservation is a useful tool in captive fish reproduction management, that is to synchronize gamete production, especially in the case of species as the european eel, where the time of female spawning readiness is unpredictable. several protocols to cryopreserve sperm of this species have been described, but until recently fertilization trials were not feasible. this study evaluated the effect of cold storage of diluted sperm prior to fertilizations and tested whether a previously def ...201627189043
development of sperm vitrification protocols for freshwater fish (eurasian perch, perca fluviatilis) and marine fish (european eel, anguilla anguilla).vitrification was successfully applied to the sperm of two fish species, the freshwater eurasian perch (perca fluviatilis) and marine european eel (anguilla anguilla). sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (casa). additional sperm quality parameters ...201727174751
ultrasonographic predictors of response of european eels (anguilla anguilla) to hormonal treatment for induction of ovarian development.objective to examine ultrasonographic predictors of ovarian development in european eels (anguilla anguilla) undergoing hormonal treatment for assisted reproduction. animals 83 female european eels. procedures eels received weekly im injections of salmon pituitary extract (first injection = week 1). ultrasonography of the ovaries was performed twice during hormonal treatment (weeks 7 and 11). eels were identified on the basis of body weight as having an adequate response by weeks 14 to 20 or an ...201627111015
sodium affects the sperm motility in the european eel.the role of seminal plasma sodium and activation media sodium on sperm motility was examined by selectively removing the element from these two media, in european eel sperm. sperm size (sperm head area) was also measured using an asma (automated sperm morphometry analyses) system, in the different conditions. intracellular sodium [na(+)]i was quantitatively analyzed by first time in the spermatozoa from a marine fish species. measurement of [na(+)]i was done before and after motility activation, ...201627085371
evaluating the adaptive potential of the european eel: is the immunogenetic status recovering?the recent increased integration of evolutionary theory into conservation programs has greatly improved our ability to protect endangered species. a common application of such theory links population dynamics and indices of genetic diversity, usually estimated from neutrally evolving markers. however, some studies have suggested that highly polymorphic adaptive genes, such as the immune genes of the major histocompatibility complex (mhc), might be more sensitive to fluctuations in population dyn ...201627077000
an ultrastructural and immunohistochemical analysis of the outer plexiform layer of the retina of the european silver eel (anguilla anguilla l).here we studied the ultrastructural organization of the outer retina of the european silver eel, a highly valued commercial fish species. the retina of the european eel has an organization very similar to most vertebrates. it contains both rod and cone photoreceptors. rods are abundantly present and immunoreactive for rhodopsin. cones are sparsely present and only show immunoreactivity for m-opsin and not for l-, s- or uv-cone opsins. as in all other vertebrate retinas, müller cells span the wid ...201627032102
temperature modulates testis steroidogenesis in european eel.this study evaluates the effects of temperature on hcg-induced spermatogenesis in european eel (anguilla anguilla), subjected to three thermal regimes: t10: 10°c (first 4weeks), 15°c (next 3weeks) and 20°c (last 6weeks); t15: 15°c (first 4weeks) and 20°c (last 9weeks); and t20: constant 20°c for the duration of the experiment. at 10°c, maturation stopped in the a spermatogonial stage (spg1), and no further maturation was observed until the temperature was ≥15°c. with the aim of explaining these ...201627013359
phagocytic cell responses to silica-coated dithiocarbamate-functionalized iron oxide nanoparticles and mercury co-exposures in anguilla anguilla l.immune system responses in fish are considered as suitable and sensitive biomarkers for monitoring aquatic pollution. however, a clear knowledge gap persists in the literture on the immunotoxic potential of engineered nanoparticles toward aquatic organisms such as fish. employing major enzymatic- (glutathione reductase, gr; glutathione peroxidase, gpx; glutathione sulfo-transferase, gst; catalase, cat) and thiol- (non-protein thiols, np-sh; total glutathione, tgsh)-based defense biomarkers, this ...201626976012
are biometric parameters helpful to assess the health risk of consuming organochlorine compounds contaminated silver european eel (anguilla anguilla)?several organochlorine compounds (ocs) were measured in european eels from the tevere river (italy). it followed that some of them are still important chemical contaminants. concentrations of dichlorodiphenyltrichloroethanes (ddts) are hazardous for the consumer health; those of the 6 indicator polychlorinated biphenyls (pcbs) are often close to the current european maximum residue limit and always higher than the former limit. the relationship between oc concentrations, biometric parameters and ...201626953718
rapid recovery following short-term acoustic disturbance in two fish species.noise from human activities is known to impact organisms in a variety of taxa, but most experimental studies on the behavioural effects of noise have focused on examining responses associated with the period of actual exposure. unlike most pollutants, acoustic noise is generally short-lived, usually dissipating quickly after the source is turned off or leaves the area. in a series of experiments, we use established experimental paradigms to examine how fish behaviour and physiology are affected, ...201626909193
to boldly climb: behavioural and cognitive differences in migrating european glass eels.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 expe ...201626909192
first evidence of european eels exiting the mediterranean sea during their spawning migration.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 th ...201626906289
kleptoparasitism and aggressiveness are influenced by standard metabolic rate in eels.kleptoparasitism refers to either interspecific or intraspecific stealing of food already procured by other species or individuals. within a given species, individuals might differ in their propensity to use such a tactic, in a similar manner to which they differ in their general level of aggressiveness. standard metabolic rate is often viewed as a proxy for energy requirements. for this reason, it should directly impact on both kleptoparasitism and aggressiveness when individuals have to share ...201626861178
diet-induced phenotypic plasticity in european eel (anguilla anguilla).two phenotypes are present within the european eel population: broad-heads and narrow-heads. the expression of these phenotypes has been linked to several factors, such as diet and differential growth. the exact factors causing this dimorphism, however, are still unknown. in this study, we performed a feeding experiment on glass eels from the moment they start to feed. eels were either fed a hard diet, which required biting and spinning behavior, or a soft diet, which required suction feeding. w ...201626847560
thyroid endocrine status of wild european eels (anguilla anguilla) in the loire (france). relationships with organic contaminant body 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 ...201626845177
using a novel "integrated biomarker proteomic" index to assess the effects of freshwater pollutants in european eel peripheral blood mononuclear cells.using proteomic data as biomarkers of environmental pollution has the potential to be of a great interest in ecological risk assessment as they constitute early warning indicators of ecologically relevant effects on biological systems. to develop such specific and sensitive biomarkers, the use of a set of proteins is required and the identification of protein expression signatures (pes) may reflect the exposure to specific classes of pollutants. using 2d-dige (differential in gel electrophoresis ...201626785284
species complexes and phylogenetic lineages of hoferellus (myxozoa, cnidaria) including revision of the genus: a problematic case for taxonomy.myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts dna based phylogenies. freshwater species of the genus hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. this study aims to increase our understanding of their molecular diversity and development, aspects about which little is known, and to generate a molecular diagnostic tool to discriminate between different pathoge ...201626754529
brominated, chlorinated and mixed brominated/chlorinated persistent organic pollutants in european eels (anquilla anquilla) from latvian lakes.fifty-eight european eel (anquilla anquilla) specimens collected from five latvian lakes were investigated for six groups of persistent organic pollutants (pops), including polychlorinated, polybrominated and mixed bromo-chloro dibenzo-p-dioxins and dibenzofurans (pcdd/dfs, pbdd/dfs and pxdd/dfs), polychlorinated and mixed bromo-chloro biphenyls (pcbs and pxbs) and polybrominated diphenyl ethers (pbdes). pcdd/dfs and pcbs were found to occur in the range 0.85-15.8 pg total-who2005-teq g(-1) f.w. ...201626730547
freshwater and coastal migration patterns in the silver-stage eel anguilla anguilla.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 s ...201626707686
condition-dependent physiological and behavioural responses to anthropogenic noise.anthropogenic (man-made) noise, a global pollutant of international concern, is known to affect the physiology and behaviour of a range of organisms. however, experimental studies have tended to focus on trait means; intra-population variation in responses are likely, but have rarely been explored. here we use established experimental methods to demonstrate a condition-dependent effect of additional noise. we show that juvenile european eels (anguilla anguilla) in good condition do not respond d ...201626686756
the effects of hypoxic bradycardia and extracellular hco3(-)/co2 on hypoxic performance in the eel heart.during hypoxia, fishes exhibit a characteristic hypoxic bradycardia, the functional significance of which remains debated. here, we investigated the hypothesis that hypoxic bradycardia primarily safeguards cardiac performance. in preparations from the european eel (anguilla anguilla), a decrease in stimulation frequency from 40 to 15 beats min(-1), which replicates hypoxic bradycardia in vivo, vastly improved cardiac performance during hypoxia in vitro. as eels display dramatic shifts in extrace ...201626596533
selection of best-performing reference gene products for investigating transcriptional regulation across silvering in the european eel (anguilla anguilla).the focus of the present study was to set a methodological approach for evaluating molecular mechanisms underlying silvering transformation in the european eel, anguilla anguilla. silvering is a tightly controlled process during which eels undergo significant morphological, physiological and behavioral changes, pre-adapting for the oceanic spawning migration. female eels showing different silver indexes were caught in different seasons in the comacchio lagoon (north adriatic sea, italy). isolate ...201526593703
detecting the exposure to cd and pcbs by means of a non-invasive transcriptomic approach in laboratory and wild contaminated european eels (anguilla anguilla).detecting and separating specific effects of contaminants in a multi-stress field context remain a major challenge in ecotoxicology. in this context, the aim of this study was to assess the usefulness of a non-invasive transcriptomic method, by means of a complementary dna (cdna) microarray comprising 1000 candidate genes, on caudal fin clips. fin gene transcription patterns of european eels (anguilla anguilla) exposed in the laboratory to cadmium (cd) or a polychloro-biphenyl (pcbs) mixture but ...201626566612
rad sequencing reveals within-generation polygenic selection in response to anthropogenic organic and metal contamination in north atlantic eels.measuring the effects of selection on the genome imposed by human-altered environment is currently a major goal in ecological genomics. given the polygenic basis of most phenotypic traits, quantitative genetic theory predicts that selection is expected to cause subtle allelic changes among covarying loci rather than pronounced changes at few loci of large effects. the goal of this study was to test for the occurrence of polygenic selection in both north atlantic eels (european eel, anguilla angu ...201626562221
cutaneous myxidiosis in european eel, anguilla anguilla (linnaeus, 1758): histopathology, histochemistry and laminin immunohistochemistry.histopathology, histochemistry and immunohistochemistry of the integument of european eel, anguilla anguilla (linnaeus, 1758), infected by myxidium sp. are reported. skin samples from affected and unaffected eels were dissected, formalin fixed, paraffin embedded, sectioned and stained with h&e, periodic acid-schiff's staining method, alcian blue 8 gx ph 2.5/periodic acid-schiff's and mccallum-goodpasture's gram stain. moreover, immunohistochemistry was performed using a primary polyclonal lamini ...201626525491
a question of origin: dioxin-like pcbs and their relevance in stock management of european eels.the stock of european eel (anguilla anguilla l.) has reached an all-time low in 2011. spawner quality of mature eels in terms of health status and fitness is considered one of the key elements for successful migration and reproduction. dioxin-like polychlorinated biphenyls (dl-pcbs) are known persistent organic pollutants potentially affecting the reproductive capability and health status of eels throughout their entire lifetime. in this study, muscle tissue samples of 192 european eels of all c ...201626477019
role of calcium on the initiation of sperm motility in the european eel.sperm from european eel males treated with hcgrec was washed in a calcium free extender, and sperm motility was activated both in the presence (seawater, sw) and in the absence of calcium (nacl+edta), and treated with calcium inhibitors or modulators. the sperm motility parameters were evaluated by a computer-assisted sperm analysis (casa) system, and changes in the [ca(2+)]i fluorescence (and in [na(+)]i in some cases) were evaluated by flow cytometry. after sperm motility was activated in a me ...201626459984
comparison of swimming capacity and energetics of migratory european eel (anguilla anguilla) and new zealand short-finned eel (a. australis).the spawning migration of the european eel (anguilla anguilla) can cover more than 6000 km, while that of the new zealand short-finned eel (a. australis) is assumed to be approximately 3000 km. since these species are expected to show adaptive traits to such an important lifetime event, we hypothesized differences in swimming capacity and energetics as a response to this adaptation. in an experimental swimming respirometer set-up, critical swimming speed (ucrit), optimal swimming speed (uopt), m ...201526441675
abundance of specific mrna transcripts impacts hatching success in european eel, anguilla anguilla l.maternal mrna governs early embryonic development in fish and variation in abundance of maternal transcripts may contribute to variation in embryonic survival and hatch success in european eel, anguilla anguilla. previous studies have shown that quantities of the maternal gene products β-tubulin, insulin-like growth factor 2 (igf2), nucleoplasmin (npm2), prohibitin 2 (phb2), phosphatidylinositol glycan biosynthesis class f protein 5 (pigf5), and carnitine o-palmitoyltransferase liver isoform-lik ...201626415730
rescheduling the process of nanoparticle removal used for water mercury remediation can increase the risk to aquatic organism: evidence of innate immune functions modulation in european eel (anguilla anguilla l.).this study aimed to assess the mechanisms of innate immune function responses to silica-coated iron oxide nanoparticle functionalized with dithiocarbamate groups (ionp) exposure alone and its associated mercury (hg) in european eel (anguilla anguilla l.) phagocytes isolated from peritoneum (p-phagocytes), gill (g-phagocytes), head kidney (hk-phagocytes) and spleen (s-phagocytes). the study evaluated viability, phagocytosis, oxidative burst activity (oba) and lipid peroxidation (lpo). four groups ...201526396010
chemical elements in the muscle tissues of european eel (anguilla anguilla) from selected lakes in 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 b ...201526334326
toxic textile dyes accumulate in wild european eel anguilla anguilla.dyes are used to stain inks, paints, textile, paper, leather and household products. they are omnipresent, some are toxic and may threaten our environment, especially aquatic ecosystems. the presence of residues of sixteen dyes (triarylmethanes, xanthenes, phenothiazines and phenoxazines) and their metabolites was analyzed in muscle tissue samples of individual yellow-phased european eels (anguilla anguilla) from 91 locations in belgian rivers, canals and lakes sampled between 2000 and 2009 usin ...201526291760
musculoskeletal anatomy and feeding performance of pre-feeding engyodontic larvae of the european eel (anguilla anguilla).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, 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 p ...201526278932
demonstration of the coexistence of duplicated lh receptors in teleosts, and their origin in ancestral actinopterygians.pituitary gonadotropins, fsh and lh, control gonad activity in vertebrates, via binding to their respective receptors, fshr and lhr, members of gpcr superfamily. until recently, it was accepted that gnathostomes possess a single fshr and a single lhr, encoded by fshr and lhcgr genes. we reinvestigated this question, focusing on vertebrate species of key-phylogenetical positions. genome analyses supported the presence of a single fshr and a single lhcgr in chondrichthyans, and in sarcopterygians ...201526271038
signatures of natural selection between life cycle stages separated by metamorphosis in european eel.species showing complex life cycles provide excellent opportunities to study the genetic associations between life cycle stages, as selective pressures may differ before and after metamorphosis. the european eel presents a complex life cycle with two metamorphoses, a first metamorphosis from larvae into glass eels (juvenile stage) and a second metamorphosis into silver eels (adult stage). we tested the hypothesis that different genes and gene pathways will be under selection at different life st ...201526268725
head shape dimorphism in european glass eels (anguilla anguilla).the life cycle of the european eel (anguilla anguilla) remained a mystery until the 20th century, when schmidt discovered that the sargasso sea was its spawning area. however, many aspects of the eel's life cycle remain poorly understood. among these is the bimodal distribution in head shape, with broad- and narrowheaded phenotypes reported in the yellow eel stage. although this has been linked to dietary preferences of the yellow eels, very little is known about why, how and when this dimorphis ...201526265585
climbing experience in glass eels: a cognitive task or a matter of physical capacities?the european eel is a panmictic species, whose decline has been recorded since the last 30 years. among human-induced environmental factors of decline, the impact of water dams during species migration is questioned. indeed, water impoundments can be a severe obstacle for young eels trying to reach the upstream freshwater zones, even if they are equipped with fish-friendly passes. the passage by such devices could be an important event shaping the outcome of the future life and life history trai ...201526260433
changes in ovarian gene expression profiles and plasma hormone levels in maturing european eel (anguilla anguilla); biomarkers for broodstock selection.complete sexual maturation of european eels (anguilla anguilla) in captivity can only be achieved via injections with gonadotropins. for female eels this procedure takes 4-6months and the response ranges from "unresponsive" to final maturation and ovulation. reproductive success could be significantly increased via early selection of responders based on predictive markers and minimally invasive sampling methods. to get a better understanding of the genetic background of ovarian maturation of the ...201626255685
transcriptomic profiling of male european eel (anguilla anguilla) livers at sexual maturity.the european eel anguilla anguilla has a complex life cycle that includes freshwater, seawater and morphologically distinct stages as well as two extreme long distance migrations. eels do not feed as they migrate across the atlantic to the sargasso sea but nevertheless reach sexual maturity before spawning. it is not yet clear how existing energy stores are used to reach the appropriate developmental state for reproduction. since the liver is involved in energy metabolism, protein biosynthesis a ...201526253995
maternally transferred dioxin-like compounds can affect the reproductive success of european eel.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, b ...201626223357
a physiologically based toxicokinetic (pbtk) model for moderately hydrophobic organic chemicals in the european eel (anguilla anguilla).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 ...201526218567
gonadal transcriptome analysis of wild contaminated female european eels during artificial gonad maturation.since the early 1980s, the population of european eels (anguilla anguilla) has dramatically declined. nowadays, the european eel is listed on the red list of threatened species (iucn red list) and is considered as critically endangered of extinction. pollution is one of the putative causes for the collapse of this species. among their possible effects, contaminants gradually accumulated in eels during their somatic growth phase (yellow eel stage) would be remobilized during their reproductive mi ...201526159298
influence of β-glucan leiber(®)beta-s on selected innate immunity parameters of european eel (anguilla anguilla) in an intensive farming system.nutritional support plays an important role in promoting high cellular and humoral innate immunity activity and in preventing outbreaks of disease. the effects of β-glucan leiber(®)beta-s dietary supplementation on selected nonspecific immune parameters in juvenile european eel (anguilla anguilla) in an intensive culture system were studied. the fish were fed commercial pellets containing either 0 (control group) or 200 mg leiber(®)beta-s kg-1 of feed (glucan-fed group). after four and eight wee ...201526155177
response of seaward-migrating european eel (anguilla anguilla) to manipulated flow fields.anthropogenic structures (e.g. weirs and dams) fragment river networks and restrict the movement of migratory fish. poor understanding of behavioural response to hydrodynamic cues at structures currently limits the development of effective barrier mitigation measures. this study aimed to assess the effect of flow constriction and associated flow patterns on eel behaviour during downstream migration. in a field experiment, we tracked the movements of 40 tagged adult european eels (anguilla anguil ...201526136454
macroparasites and their communities of the european eel anguilla anguilla (linnaeus) in the czech republic.this paper summarises the results of parasitological examinations of the european eel anguilla anguilla (linnaeus) in the czech republic, carried out at the institute of parasitology, czech academy of sciences (previously the czechoslovak academy of sciences) within the period of 50 years (1958-2008). even though this survey is limited to the czech republic, it provides extensive data probably incomparable with any other study anywhere regarding the number of eels examined and parasites found. a ...201526130652
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