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1.
J Fish Biol ; 92(5): 1635-1644, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29537067

RESUMO

This study assessed the usefulness of passing euthanized Atlantic salmon Salmo salar smolts through an Archimedean screw turbine to test for external damage, as compared with live, actively swimming smolts. Scale loss was the only observed effect. Severe scale loss was 5·9 times more prevalent in euthanized turbine-passed fish (45%) than the live fish (7·6%). Additionally, distinctive patterns of scale loss, consistent with grinding between the turbine helices and housing trough, were observed in 35% of euthanized turbine-passed smolts. This distinctive pattern of scale loss was not seen in live turbine-passed smolts, nor in control groups (live and euthanized smolts released downstream of the turbine), which suggests that the altered behaviour of dead fish in turbine flows generates biased injury outcomes.


Assuntos
Meio Ambiente , Centrais Elétricas , Salmo salar , Migração Animal , Animais , Natação
2.
J Fish Biol ; 92(6): 1849-1865, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29603222

RESUMO

A total of 230 anadromous Salmo trutta (brown trout) were sampled in five sheltered coastal fjords (or sea lochs) on the Isle of Skye, Scotland, U.K., in 2016 at varying distances from active Atlantic salmon Salmo salar farms. Statistical models were developed to investigate potential correlations between salmon lice Lepeophtheirus salmonis burdens on S. trutta hosts and their proximity to S. salar farm cages. Significant correlations were found between lice burdens and fish fork length and proximity to the nearest S. salar farm. The probability of the presence of L. salmonis on fish hosts increased with fish host size and with distance from the nearest S. salar farm, but total lice burdens were highest in fish sampled near S. salar farms and decreased with distance. The proportion of different life-cycle stages of L. salmonis were also dependent on S. salar farm proximity, with higher juvenile lice numbers recorded at sites near S. salar farm cages. These results highlight the complexity of the relationship between S. trutta and L. salmonis infections on wild fish and emphasize the requirement of further research to quantify these effects to better inform conservation and management strategies, particularly in areas of active S. salar farm facilities.


Assuntos
Aquicultura , Copépodes , Doenças dos Peixes/transmissão , Salmo salar/parasitologia , Truta/parasitologia , Animais , Feminino , Doenças dos Peixes/parasitologia , Masculino , Escócia
3.
J Fish Dis ; 40(9): 1213-1222, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28084623

RESUMO

Infection patterns of the invasive Anguillicola crassus nematode were investigated in a population of the European eel Anguilla anguilla where parasite invasion is very recent, Loch Lomond, Scotland. Intensity levels of the parasite were associated with differences in fish ontogeny and trophic ecology. Although eels foraged on both fish and invertebrates, individuals which were smaller and fed on invertebrates (>70% contribution to diet) were found to contain a greater number of swim bladder parasites compared to larger eel with a predominance of fish (>60% contribution) in their diet. Within affected fish, a significant negative relationship was found between fish length and parasite intensity, with smaller individuals having higher parasite intensity than larger individuals. This study indicates that food intake and infection risk are linked in this recently infected host-parasite system. From a management perspective increasing our understanding of how infection intensity and repeated exposure is linked to resource use in an ecosystem is important for the future management of this endangered species in Europe.


Assuntos
Anguilla , Suscetibilidade a Doenças/veterinária , Dracunculoidea/fisiologia , Comportamento Alimentar , Doenças dos Peixes/epidemiologia , Infecções por Spirurida/veterinária , Sacos Aéreos/parasitologia , Anguilla/crescimento & desenvolvimento , Anguilla/fisiologia , Animais , Tamanho Corporal , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/parasitologia , Doenças dos Peixes/parasitologia , Espécies Introduzidas , Prevalência , Escócia/epidemiologia , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia
4.
J Fish Biol ; 88(4): 1648-54, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26899559

RESUMO

This study examined the abiotic and biotic characteristics of ecosystems that allow expression of a life history called ferox trout, the colloquial name given to brown trout Salmo trutta adopting a piscivorous life history strategy, an apex predator in post-glacial lakes in northern Europe. One hundred and ninety-two lakes in Scotland show evidence of currently, or historically, supporting ferox S. trutta; their presence was predicted in logistic models by larger and deeper lakes with a large catchment that also support populations of Arctic charr Salvelinus alpinus.


Assuntos
Ecossistema , Truta , Animais , Lagos , Escócia
5.
J Fish Biol ; 89(3): 1641-50, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27352823

RESUMO

Mortality rates of wild Atlantic salmon Salmo salar smolts implanted with acoustic transmitters were assessed to determine if mortality was size dependent. The routinely accepted, but widely debated, '2% transmitter mass: body mass' rule in biotelemetry was tested by extending the transmitter burden up to 12·7% of body mass in small [mean fork length (LF ) 138·3 mm, range 115-168 mm] downstream migrating S. salar smolts. Over the short timescale of emigration (range 11·9-44·5 days) through the lower river and estuary, mortality was not related to S. salar size, nor was a relationship found between mortality probability and transmitter mass: body mass or transmitter length: LF ratios. This study provides further evidence that smolt migration studies can deviate from the '2% rule' of thumb, to more appropriate study-specific measures, which enables the use of fishes representative of the body size in natural populations without undue effects.


Assuntos
Tamanho Corporal , Mortalidade , Salmo salar , Telemetria/métodos , Acústica , Migração Animal , Animais , Estuários , Rios , Salmão
6.
J Fish Biol ; 88(2): 676-89, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26707686

RESUMO

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.


Assuntos
Anguilla/fisiologia , Migração Animal , Acústica , Sistemas de Identificação Animal , Animais , Estuários , Feminino , Água Doce , Irlanda , Masculino , Rios , Telemetria , Movimentos da Água
7.
J Fish Biol ; 88(2): 580-94, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26748995

RESUMO

This study revealed between-lake genetic structuring between Coregonus lavaretus collected from the only two native populations of this species in Scotland, U.K. (Lochs Eck and Lomond) evidenced by the existence of private alleles (12 in Lomond and four in Eck) and significant genetic differentiation (FST = 0·056) across 10 microsatellite markers. Juvenile C. lavaretus originating from eggs collected from the two lakes and reared in a common-garden experiment showed clear phenotypic differences in trophic morphology (i.e. head and body shape) between these populations indicating that these characteristics were, at least partly, inherited. Microsatellite analysis of adults collected from different geographic regions within Loch Lomond revealed detectable and statistically significant but relatively weak genetic structuring (FST = 0·001-0·024) and evidence of private alleles related to the basin structure of the lake. Within-lake genetic divergence patterns suggest three possibilities for this observed pattern: (1) differential selection pressures causing divergence into separate gene pools, (2) a collapse of two formerly divergent gene pools and (3) a stable state maintained by balancing selection forces resulting from spatial variation in selection and lake heterogeneity. Small estimates of effective population sizes for the populations in both lakes suggest that the capacity of both populations to adapt to future environmental change may be limited.


Assuntos
Variação Genética , Genética Populacional , Salmonidae/genética , Alelos , Animais , Feminino , Pool Gênico , Genótipo , Lagos , Masculino , Repetições de Microssatélites , Fenótipo , Escócia
8.
J Fish Biol ; 86(6): 1873-80, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26033294

RESUMO

This study examines juvenile Anguilla anguilla (<30 cm) abundance in five study catchments on the Isle of Man. Preliminary results suggest that juvenile abundance is negatively correlated with increasing coastal current speed at river mouth entry (P < 0·05). These findings indicate that at least under some circumstances, tidally driven coastal currents may influence recruitment to freshwater habitats; therefore, it is presumed that high coastal current speed at the entry to river mouths may reduce the likelihood of freshwater entry.


Assuntos
Anguilla , Ecossistema , Movimentos da Água , Animais , Espécies em Perigo de Extinção , Estuários , Água Doce , Rios , Reino Unido
9.
J Fish Biol ; 84(5): 1614-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24773546

RESUMO

Reported here are several deviations (n = 15; 1·96%) from typical morphology in a large sample (n = 767) of European brook lamprey Lampetra planeri from a single population in the Loch Lomond catchment; this includes one specimen bearing a true anal fin. A brief review of petromyzontid teratology is provided.


Assuntos
Lampreias/anormalidades , Animais , Lagos , Escócia , Teratogênese
10.
J Fish Biol ; 85(3): 882-900, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25082262

RESUMO

Diploid and triploid brown trout Salmo trutta were acclimated for 6 weeks on two feeding regimes (floating and sinking). Thereafter, aggression and surface feeding response were compared between pairs of all diploid, all triploid and diploid and triploid S. trutta in an experimental stream. In each pair-wise matching, fish of similar size were placed in allopatry and rank was determined by the total number of aggressive interactions recorded. Dominant individuals initiated more aggression than subordinates, spent more time defending a territory and positioned themselves closer to the surface food source (Gammarus pulex), whereas subordinates occupied the peripheries. In cross ploidy trials, diploid S. trutta were more aggressive than triploid, and dominated their sibling when placed in pair-wise matchings. Surface feeding, however, did not differ statistically between ploidy irrespective of feeding regime. Triploids adopted a sneak feeding strategy while diploids expended more time defending a territory. In addition, we also tested whether triploids exhibit a similar social dominance to diploids when placed in allopatry. Although aggression was lower in triploid pairs than in the diploid and triploid pairs, a dominance hierarchy was also observed between individuals of the same ploidy. Dominant triploid fish were more aggressive and consumed more feed items than subordinate individuals. Subordinate fish displayed a darker colour index than dominant fish suggesting increased stress levels. Dominant triploid fish, however, appeared to be more tolerant of subordinate individuals and did not display the same degree of invasive aggression as seen in the diploid and diploid or diploid and triploid matchings. These novel findings suggest that sterile triploid S. trutta feed similarly but are less aggressive than diploid trout. Future studies should determine the habitat choice of triploid S. trutta after release and the interaction between wild fish and triploids during the breeding season prior to utilization of triploids as an alternative management strategy within freshwater fisheries.


Assuntos
Agressão , Comportamento Alimentar , Truta/fisiologia , Animais , Comportamento Animal , Diploide , Predomínio Social , Territorialidade , Triploidia
11.
Br J Cancer ; 108(1): 139-48, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23321516

RESUMO

BACKGROUND: Prostate cancer cell growth is dependent upon androgen receptor (AR) activation, which is regulated by specific kinases. The aim of the current study is to establish if AR phosphorylation by Cdk1 or ERK1/2 is of prognostic significance. METHODS: Scansite 2.0 was utilised to predict which AR sites are phosphorylated by Cdk1 and ERK1/2. Immunohistochemistry for these sites was then performed on 90 hormone-naive prostate cancer specimens. The interaction between Cdk1/ERK1/2 and AR phosphorylation was investigated in vitro using LNCaP cells. RESULTS: Phosphorylation of AR at serine 515 (pAR(S515)) and PSA at diagnosis were independently associated with decreased time to biochemical relapse. Cdk1 and pCdk1(161), but not ERK1/2, correlated with pAR(S515). High expression of pAR(S515) in patients with a PSA at diagnosis of ≤20 ng ml(-1) was associated with shorter time to biochemical relapse (P=0.019). This translated into a reduction in disease-specific survival (10-year survival, 38.1% vs 100%, P<0.001). In vitro studies demonstrated that treatment with Roscovitine (a Cdk inhibitor) caused a reduction in pCdk1(161) expression, pAR(S515)expression and cellular proliferation. CONCLUSION: In prostate cancer patients with PSA at diagnosis of ≤20 ng ml(-1), phosphorylation of AR at serine 515 by Cdk1 may be an independent prognostic marker.


Assuntos
Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias da Próstata/metabolismo , Purinas/farmacocinética , Receptores Androgênicos/metabolismo , Idoso , Biomarcadores Tumorais/antagonistas & inibidores , Proteína Quinase CDC2/antagonistas & inibidores , Proteína Quinase CDC2/metabolismo , Intervalo Livre de Doença , Humanos , Masculino , Fosforilação , Prognóstico , Antígeno Prostático Específico/metabolismo , Recidiva , Roscovitina , Serina/metabolismo
12.
J Fish Biol ; 83(5): 1221-33, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24580664

RESUMO

This study examined the potential biochemical and mechanical structures that may contribute to egg adhesion in European whitefish Coregonus lavaretus. Experiments showed that eggs from a population of C. lavaretus from Loch Eck remained non-adhesive in a solution chemically similar to ovarian fluid but became adhesive seconds after contact with water. Examination of the ultrastructure of the chorion showed that the morphology changed significantly after contact with water, with nodule-like protuberances attached to connective filaments on the surface present in water-hardened but not non-water hardened eggs. Biochemical analysis showed the presence of Chain A, RNase ZF-3e proteins in the chorion of water-hardened but not non-water hardened eggs. Histochemical staining of the chorion of C. lavaretus eggs showed that the externa, but not the interna, stained positively for the presence of glycoproteins. From these results, it was concluded that C. lavaretus from Loch Eck possess both anatomical and biochemical adhesive mechanisms that have been undocumented in this species so far.


Assuntos
Óvulo/química , Salmonidae , Adesividade , Animais , Córion/ultraestrutura , Proteínas de Peixes/química , Óvulo/fisiologia , Óvulo/ultraestrutura , Ribonucleases/química , Água/química
13.
J Fish Biol ; 82(5): 1708-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23639164

RESUMO

Lamprey-induced scarring of the nationally rare Coregonus lavaretus, a known host of a freshwater-resident population of European river lamprey Lampetra fluviatilis, was found to have declined precipitously since the establishment of several non-native fishes in Loch Lomond. Evidence presented in this study points to the possibility that L. fluviatilis in this lake may have altered its trophic ecology in response to the negative impact that non-native species, in particular ruffe Gymnocephalus cernuus, have had on their favoured host.


Assuntos
Lampreias/fisiologia , Perciformes/parasitologia , Salmonidae/parasitologia , Animais , Espécies Introduzidas , Lagos , Dinâmica Populacional , Escócia
14.
J Fish Biol ; 82(3): 1093-100, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23464566

RESUMO

Interspecific sneak male mating tactics between paired lamprey species are described for the first time. Although alternative mating tactics among petromyzontids have been described previously, including intraspecific sneak males, the presence of sneak male tactics between parasitic and non-parasitic forms suggests that high levels of gene flow between putative lamprey species could remain high, despite large body size discrepancies.


Assuntos
Lampreias/fisiologia , Reprodução , Comportamento Sexual Animal , Animais , Feminino , Fluxo Gênico , Lampreias/genética , Masculino
15.
Psychol Med ; 42(11): 2265-73, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22405443

RESUMO

BACKGROUND: After de-escalation techniques have failed, restraints, seclusion and/or rapid tranquillization may be used for people whose aggression is due to psychosis. Most coercive acts of health care have not been evaluated in trials. METHOD: People admitted to the emergency room of Instituto Philippe Pinel, Rio de Janeiro, Brazil, whose aggression/agitation was thought due to psychosis and for whom staff were unsure if best to restrict using physical restraints or a seclusion room, were randomly allocated to one or the other and followed up to 14 days. The primary outcomes were 'no need to change intervention early - within 1 h' and 'not restricted by 4 h'. RESULTS: A total of 105 people were randomized. Two-thirds of the people secluded were able to be fully managed in this way. Even taking into account the move out of seclusion into restraints, this study provides evidence that embarking on the less restrictive care pathway (seclusion) does not increase overall time in restriction of some sort [not restricted by 4 h: relative risk 1.09, 95% confidence interval 0.75-1.58; mean time to release: restraints 337.6 (s.d.=298.2) min, seclusion room 316.3 (s.d.=264.5) min, p=0.48]. Participants tended to be more satisfied with their care in the seclusion group (17.0% v. 11.1%) but this did not reach conventional levels of statistical significance (p=0.42). CONCLUSIONS: This study should be replicated, but suggests that opting for the least restrictive option in circumstances where there is clinical doubt does not harm or prolong coercion.


Assuntos
Agressão/psicologia , Isolamento de Pacientes/normas , Transtornos Psicóticos/terapia , Restrição Física/normas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/complicações , Resultado do Tratamento
16.
J Fish Biol ; 80(2): 387-407, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22268437

RESUMO

A key for three putative species apparently found in three geographic areas, i.e. Coregonus clupeoides (in Scotland), Coregonus stigmaticus (in England), and Coregonus pennantii (in Wales) given in a recent review was tested quantitatively using 544 individuals from nine populations. The classification success of the key was very low (27%). It was concluded that there is currently no robust evidence for the recognition of the three putative species. Furthermore, the use of phenotypic characters alone to distinguish putative species in postglacial fish species such as those of the genus Coregonus that show homoplasy in many of these traits is questioned. In the absence of further evidence, it was concluded that a single highly variable species best describes the pattern of phenotypic variation in these U.K. populations. On this basis it is argued that taxonomic subdivision of U.K. European coregonids is inappropriate and that Coregonus lavaretus should prevail as the species name applicable to all populations.


Assuntos
Especiação Genética , Fenótipo , Salmonidae/classificação , Animais , Inglaterra , Variação Genética , Salmonidae/genética , Escócia , País de Gales
17.
J Fish Biol ; 76(6): 1491-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20537027

RESUMO

Landmark-based geometric morphometric analysis was used to detect differences in scale shape between ecologically distinct phenotypes of Arctic charr Salvelinus alpinus coexisting in the same lake. Relative warp analysis and standard multivariate analyses of the partial warps, obtained after a Procrustes superimposition, showed that scale landmarks were efficient in discriminating among two closely related alternative phenotypes within each of the two lakes. In Loch Tay, S. alpinus exhibited a bimodal body size-frequency distribution among sexually mature fish, whereas in Loch Awe, S. alpinus are unimodal in body size but segregated into two distinct spawning phenotypes. In both lakes, alternative phenotypes showed significant differences in foraging ecology, habitat use and life history. It is probable that differences in scale shape reflect differences in ecology of these forms.


Assuntos
Fenótipo , Truta/anatomia & histologia , Animais , Tamanho Corporal , Feminino , Água Doce , Masculino , Escócia , Truta/genética
18.
J Fish Biol ; 77(10): 2391-404, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21155790

RESUMO

Differences in stable-isotope values, morphology and ecology in whitefish Coregonus lavaretus were investigated between the three basins of Loch Lomond. The results are discussed with reference to a genetic investigation to elucidate any substructuring or spawning site fidelity. Foraging fidelity between basins of Loch Lomond was indicated by δ¹³C and δ¹5N values of C. lavaretus muscle tissue. There was, however, no evidence of the existence of sympatric morphs in the C. lavaretus population. A previous report of two C. lavaretus'species' in Loch Lomond probably reflects natural variation between individuals within a single mixed population.


Assuntos
Ecossistema , Fenótipo , Salmonidae/fisiologia , Animais , Isótopos de Carbono/metabolismo , Comportamento Alimentar , Feminino , Cabeça/anatomia & histologia , Masculino , Repetições de Microssatélites , Isótopos de Nitrogênio/metabolismo , Salmonidae/anatomia & histologia , Escócia
20.
East Mediterr Health J ; 15(3): 648-52, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19731781

RESUMO

Health research in the Syrian Arab Republic faces many difficulties, including limited funds, infrastructure and means of dissemination. In a search of Medline and Embase databases in March 2006 we extracted data on 386 biomedical papers originating from the Syrian Arab Republic. Embase had the superior coverage. A total of 64% were published in journals from Europe, 22% from North American journals and 12% in periodicals from the Middle East. Output of papers increased by 1.4 articles/year since 1979. The topics of 57% of papers were biomedical, with the remainder being pure science or agricultural/veterinarian issues. Dentistry, public health and surgery were the commonest subjects of the biomedical papers. Funding was largely from government.


Assuntos
Bibliometria , Bases de Dados Bibliográficas/estatística & dados numéricos , MEDLINE/estatística & dados numéricos , Publicações Periódicas como Assunto/estatística & dados numéricos , Editoração/estatística & dados numéricos , Indexação e Redação de Resumos/estatística & dados numéricos , Europa (Continente) , Humanos , Oriente Médio , América do Norte , Pesquisa/organização & administração , Apoio à Pesquisa como Assunto/organização & administração , Síria
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