Base de dados : MEDLINE
Pesquisa : B01.050.150.900.649.313.750.600.700 [Categoria DeCS]
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  1 / 2162 MEDLINE  
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[PMID]:29320573
[Au] Autor:Beltran RS; Ruscher-Hill B; Kirkham AL; Burns JM
[Ad] Endereço:Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America.
[Ti] Título:An evaluation of three-dimensional photogrammetric and morphometric techniques for estimating volume and mass in Weddell seals Leptonychotes weddellii.
[So] Source:PLoS One;13(1):e0189865, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Body mass dynamics of animals can indicate critical associations between extrinsic factors and population vital rates. Photogrammetry can be used to estimate mass of individuals in species whose life histories make it logistically difficult to obtain direct body mass measurements. Such studies typically use equations to relate volume estimates from photogrammetry to mass; however, most fail to identify the sources of error between the estimated and actual mass. Our objective was to identify the sources of error that prevent photogrammetric mass estimation from directly predicting actual mass, and develop a methodology to correct this issue. To do this, we obtained mass, body measurements, and scaled photos for 56 sedated Weddell seals (Leptonychotes weddellii). After creating a three-dimensional silhouette in the image processing program PhotoModeler Pro, we used horizontal scale bars to define the ground plane, then removed the below-ground portion of the animal's estimated silhouette. We then re-calculated body volume and applied an expected density to estimate animal mass. We compared the body mass estimates derived from this silhouette slice method with estimates derived from two other published methodologies: body mass calculated using photogrammetry coupled with a species-specific correction factor, and estimates using elliptical cones and measured tissue densities. The estimated mass values (mean ± standard deviation 345±71 kg for correction equation, 346±75 kg for silhouette slice, 343±76 kg for cones) were not statistically distinguishable from each other or from actual mass (346±73 kg) (ANOVA with Tukey HSD post-hoc, p>0.05 for all pairwise comparisons). We conclude that volume overestimates from photogrammetry are likely due to the inability of photo modeling software to properly render the ventral surface of the animal where it contacts the ground. Due to logistical differences between the "correction equation", "silhouette slicing", and "cones" approaches, researchers may find one technique more useful for certain study programs. In combination or exclusively, these three-dimensional mass estimation techniques have great utility in field studies with repeated measures sampling designs or where logistic constraints preclude weighing animals.
[Mh] Termos MeSH primário: Biometria/métodos
Fotogrametria/métodos
Focas Verdadeiras/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Tamanho Corporal
Peso Corporal
Feminino
Imagem Tridimensional
Gravidade Específica
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180111
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189865


  2 / 2162 MEDLINE  
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[PMID]:29251588
[Au] Autor:Zhou MY; Zhang YJ; Zhang XY; Yang XD; He HL; Ning D; Du Z
[Ad] Endereço:1​Shandong Provincial Key Laboratory of Fine Chemicals, School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, PR China.
[Ti] Título:Flavobacterium phocarum sp. nov., isolated from soils of a seal habitat in Antarctica.
[So] Source:Int J Syst Evol Microbiol;68(2):536-541, 2018 Feb.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A Gram-stain-negative, yellow-pigmented, non-flagellated, gliding, rod-shaped, oxidase-negative and catalase-positive bacterium, designated SE14 , was isolated from soil on King George Island, South Shetland Islands, Antarctica. Strain SE14 grew at 4-25 °C (optimum, 20 °C), at pH 6.0-9.0 (optimum, pH 7.0-7.5) and with 0-3.0 % NaCl (optimum, 1.0-1.5 %), and could not produce flexirubin-type pigments. 16S rRNA gene sequence analysis showed the the isolate belonged to the genus Flavobacterium. Strain SE14 had the highest 16S rRNA gene sequence similarity to Flavobacterium antarcticum, F. tegetincola and F. degerlachei with 95.8, 95.5 and 95.2 %, respectively. The strain SE14 consisted of a clade with Flavobacteriumnoncentrifugens (16S rRNA gene sequence similarity 94.9 %) and F. qiangtangense (16S rRNA gene sequence similarity 94.2 %) and simultaneously formed a distinct phyletic lineage in the neighbour-joining phylogenetic tree. Polar lipids of the strain included phosphatidylethanolamine and four unidentified aminolipids. Strain SE14 contained anteiso-C15 : 0, iso-C15 : 0 and a mixture of iso-C15 : 0 2-OH and/or C16 : 1ω7c as the main fatty acids, and the only respiratory quinone was menaquinone-6. The genomic DNA G+C content was 42.3 mol%. The polyphasic taxonomic study revealed that strain SE14 belongs to a novel species within the genus Flavobacterium , and the name Flavobacterium phocarum sp. nov. is proposed. The type strain is SE14 (=CCTCC AB 2017225 =KCTC 52612 ).
[Mh] Termos MeSH primário: Flavobacterium/classificação
Filogenia
Focas Verdadeiras
Microbiologia do Solo
[Mh] Termos MeSH secundário: Animais
Regiões Antárticas
Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
Ácidos Graxos/química
Flavobacterium/genética
Flavobacterium/isolamento & purificação
Fosfatidiletanolaminas/química
Pigmentação
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
Vitamina K 2/análogos & derivados
Vitamina K 2/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Phosphatidylethanolamines); 0 (RNA, Ribosomal, 16S); 11032-49-8 (Vitamin K 2); 39382-08-6 (phosphatidylethanolamine); 71ANL51TLA (menaquinone 6)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002535


  3 / 2162 MEDLINE  
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[PMID]:29211797
[Au] Autor:Vacquie-Garcia J; Lydersen C; Biuw M; Haug T; Fedak MA; Kovacs KM
[Ad] Endereço:Norwegian Polar Institute, Fram Centre, Tromsø, Norway.
[Ti] Título:Hooded seal Cystophora cristata foraging areas in the Northeast Atlantic Ocean-Investigated using three complementary methods.
[So] Source:PLoS One;12(12):e0187889, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Identifying environmental characteristics that define the ecological niche of a species is essential to understanding how changes in physical conditions might affect its distribution and other aspects of its ecology. The present study used satellite relay data loggers (SRDLs) to study habitat use by Northeast Atlantic hooded seals (N = 20; 9 adult females, 3 adult males, and 8 juveniles). Three different methods were used in combination to achieve maximum insight regarding key foraging areas for hooded seals in this region, which have decline by 85% in recent decades: 1) first passage time (FPT); 2) vertical transit rate and; 3) change in dive drift rate. Generalized additive mixed models (GAMM) were applied to each method to determine whether specific habitat characteristics were associated with foraging. Separate models were run for the post-molting and the post-breeding seasons; sex and age classes were included in the GAMMs. All three methods highlighted a few common geographic areas as being important foraging zones; however, there were also some different areas identified by the different methods, which highlights the importance of using multiple indexes when analyzing tracking and diving data to study foraging behavior. Foraging occurred most commonly in relatively shallow areas with high Sea Surface Temperatures (SST), corresponding to continental shelf areas with Atlantic Water masses. All age and sex classes overlapped spatially to some extent, but the different age and sex groups showed differences in the bathymetry of their foraging areas as well as in their vertical use of the water column. When foraging, pups dove in the upper part of the water column in relatively deep areas. Adult females foraged relatively shallowly in deep water areas too, though in shallower areas than pups. Adult males foraged close to the bottom in shallower areas.
[Mh] Termos MeSH primário: Comportamento Alimentar
Focas Verdadeiras/fisiologia
[Mh] Termos MeSH secundário: Animais
Oceano Atlântico
Mergulho
Ecossistema
Feminino
Masculino
Movimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171229
[Lr] Data última revisão:
171229
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171207
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0187889


  4 / 2162 MEDLINE  
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[PMID]:28743556
[Au] Autor:Martinez B; Scheibner M; Soñanez-Organis JG; Jaques JT; Crocker DE; Ortiz RM
[Ad] Endereço:Department of Molecular and Cellular Biology, University of California Merced, 5200 North Lake Road, Merced, CA 95343, USA. Electronic address: bmartinez26@ucmerced.edu.
[Ti] Título:Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.
[So] Source:Gen Comp Endocrinol;252:36-47, 2017 Oct 01.
[Is] ISSN:1095-6840
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals.
[Mh] Termos MeSH primário: Jejum/metabolismo
Focas Verdadeiras/metabolismo
Transdução de Sinais
Hormônios Tireóideos/metabolismo
[Mh] Termos MeSH secundário: Animais
Jejum/sangue
Iodeto Peroxidase/metabolismo
Modelos Biológicos
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Receptores dos Hormônios Tireóideos/metabolismo
Focas Verdadeiras/sangue
Hormônios Tireóideos/sangue
Hormônios Tireóideos/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Messenger); 0 (Receptors, Thyroid Hormone); 0 (Thyroid Hormones); EC 1.11.1.8 (Iodide Peroxidase)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171222
[Lr] Data última revisão:
171222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE


  5 / 2162 MEDLINE  
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[PMID]:28934239
[Au] Autor:Whatmore AM; Dawson C; Muchowski J; Perrett LL; Stubberfield E; Koylass M; Foster G; Davison NJ; Quance C; Sidor IF; Field CL; St Leger J
[Ad] Endereço:FAO/WHO Collaborating Centre for Brucellosis, OIE Brucellosis Reference Laboratory, Animal and Plant Health Agency, Addlestone, Surrey, United Kingdom.
[Ti] Título:Characterisation of North American Brucella isolates from marine mammals.
[So] Source:PLoS One;12(9):e0184758, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Extension of known ecological niches of Brucella has included the description of two novel species from marine mammals. Brucella pinnipedialis is associated predominantly with seals, while two major Brucella ceti clades, most commonly associated with porpoises or dolphins respectively, have been identified. To date there has been limited characterisation of Brucella isolates obtained from marine mammals outside Northern European waters, including North American waters. To address this gap, and extend knowledge of the global population structure and host associations of these Brucella species, 61 isolates from marine mammals inhabiting North American waters were subject to molecular and phenotypic characterisation enabling comparison with existing European isolates. The majority of isolates represent genotypes previously described in Europe although novel genotypes were identified in both B. ceti clades. Harp seals were found to carry B. pinnipedialis genotypes previously confined to hooded seals among a diverse repertoire of sequence types (STs) associated with this species. For the first time Brucella isolates were characterised from beluga whales and found to represent a number of distinct B. pinnipedialis genotypes. In addition the known host range of ST27 was extended with the identification of this ST from California sea lion samples. Finally the performance of the frequently used diagnostic tool Bruce-ladder, in differentiating B. ceti and B. pinnipedialis, was critically assessed based on improved knowledge of the global population structure of Brucella associated with marine mammals.
[Mh] Termos MeSH primário: Beluga/microbiologia
Brucella/genética
Brucella/isolamento & purificação
Leões-Marinhos/microbiologia
Focas Verdadeiras/microbiologia
[Mh] Termos MeSH secundário: Animais
Genótipo
Tipagem Molecular
América do Norte
Oceanos e Mares
Fenótipo
Filogenia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184758


  6 / 2162 MEDLINE  
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[PMID]:28902905
[Au] Autor:Malpress V; Bestley S; Corney S; Welsford D; Labrousse S; Sumner M; Hindell M
[Ad] Endereço:Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia.
[Ti] Título:Bio-physical characterisation of polynyas as a key foraging habitat for juvenile male southern elephant seals (Mirounga leonina) in Prydz Bay, East Antarctica.
[So] Source:PLoS One;12(9):e0184536, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Antarctic coastal polynyas are persistent open water areas in the sea ice zone, and regions of high biological productivity thought to be important foraging habitat for marine predators. This study quantified southern elephant seal (Mirounga leonina) habitat use within and around the polynyas of the Prydz Bay region (63°E- 88°E) in East Antarctica, and examined the bio-physical characteristics structuring polynyas as foraging habitat. Output from a climatological regional ocean model was used to provide context for in situ temperature-salinity vertical profiles collected by tagged elephant seals and to characterise the physical properties structuring polynyas. Biological properties were explored using remotely-sensed surface chlorophyll (Chl-a) and, qualitatively, historical fish assemblage data. Spatially gridded residence time of seals was examined in relation to habitat characteristics using generalized additive mixed models. The results showed clear polynya usage during early autumn and increasingly concentrated usage during early winter. Bathymetry, Chl-a, surface net heat flux (representing polynya location), and bottom temperature were identified as significant bio-physical predictors of the spatio-temporal habitat usage. The findings from this study confirm that the most important marine habitats for juvenile male southern elephant seals within Prydz Bay region are polynyas. A hypothesis exists regarding the seasonal evolution of primary productivity, coupling from surface to subsurface productivity and supporting elevated rates of secondary production in the upper water column during summer-autumn. An advancement to this hypothesis is proposed here, whereby this bio-physical coupling is likely to extend throughout the water column as it becomes fully convected during autumn-winter, to also promote pelagic-benthic linkages important for benthic foraging within polynyas.
[Mh] Termos MeSH primário: Ecossistema
Comportamento Alimentar
Camada de Gelo
Focas Verdadeiras/fisiologia
[Mh] Termos MeSH secundário: Animais
Regiões Antárticas
Masculino
Estações do Ano
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170914
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184536


  7 / 2162 MEDLINE  
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[PMID]:28821186
[Au] Autor:Abadía-Cardoso A; Freimer NB; Deiner K; Garza JC
[Ad] Endereço:Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Carretera Tijuana-Ensenada Km 103, Pedregal Playitas, 22860 Ensenada, BC, Mexico; University of California, Santa Cruz, 110 McAllister Way, Santa Cruz, CA 95060; Southwest Fisheries Science Center, National Marine Fisheries Servi
[Ti] Título:Molecular Population Genetics of the Northern Elephant Seal Mirounga angustirostris.
[So] Source:J Hered;108(6):618-627, 2017 Sep 01.
[Is] ISSN:1465-7333
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The northern elephant seal, Mirounga angustirostris, was heavily hunted and declared extinct in the 19th century. However, a colony remained on remote Guadalupe Island, Mexico and the species has since repopulated most of its historical distribution. Here, we present a comprehensive evaluation of genetic variation in the species. First, we assess the effect of the demographic bottleneck on microsatellite variability and compare it with that found in other pinnipeds, demonstrating levels of variation similar to that in species that continue to be threatened with extinction. Next, we use sequence data from these markers to demonstrate that some of the limited polymorphism predates the bottleneck. However, most contemporary variation appears to have arisen recently and persisted due to exponential growth. We also describe how we use the range in allele size of microsatellites to estimate ancestral effective population size before the bottleneck, demonstrating a large reduction in effective size. We then employ a classical method for bacteria to estimate the microsatellite mutation rate in the species, deriving an estimate that is extremely similar to that estimated for a similar set of loci in humans, indicating consistency of microsatellite mutation rates in mammals. Finally, we find slight significant structure between some geographically separated colonies, although its biological significance is unclear. This work demonstrates that genetic analysis can be useful for evaluating the population biology of the northern elephant seal, in spite of the bottleneck that removed most genetic variation from the species.
[Mh] Termos MeSH primário: Variação Genética
Genética Populacional
Focas Verdadeiras/genética
[Mh] Termos MeSH secundário: Alelos
Animais
Sequência de Bases
California
Frequência do Gene
México
Repetições de Microssatélites
Taxa de Mutação
Densidade Demográfica
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170914
[Lr] Data última revisão:
170914
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170820
[St] Status:MEDLINE
[do] DOI:10.1093/jhered/esx053


  8 / 2162 MEDLINE  
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[PMID]:28796843
[Au] Autor:Trukhanova IS; Grachev AI; Somov AG; Burkanov VN; Laidre KL; Boveng PL
[Ad] Endereço:Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, Washington, United States of America.
[Ti] Título:The commercial harvest of ice-associated seals in the Sea of Okhotsk, 1972-1994.
[So] Source:PLoS One;12(8):e0182725, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Sealing log books from 75 out of 79 commercial harvest cruises carried out between 1972 and 1994 in the Sea of Okhotsk, Russia, were analyzed to describe spatial and temporal allocation of ice-associated seal harvest effort, species composition of catches, total harvest rates, and related parameters for species including ringed (Pusa hispida), ribbon (Histriophoca fasciata), bearded (Erignathus barbatus) and spotted (Phoca largha) seal. Variations in catch per unit effort were explored in relation to year, sea ice conditions, day of the year, and geographic location. In most years, the harvest was predominantly represented by ringed seals (mean = 0.43, range 0.25-0.67), followed by ribbon (mean = 0.31, range 0.15-0.43), spotted (mean = 0.19, range 0.11-0.35) and bearded seals (mean = 0.07, range 0.03-0.14). The struck-and-lost percentages were as high as 30-35% for ringed, bearded and spotted seals and 15-20% for ribbon seals. Catch per unit effort (number of seals/skiff*day) for ringed, ribbon, and spotted seals had a similar seasonal pattern with a distinct spike in catches for spotted seals in the first week of May, for ribbon seals in the last week of May, and for ringed seals in the second week of June. Catches of bearded seals showed a less pronounced temporal structure with a gradual increase toward the end of the harvest season in the majority of years. Spatial distribution of harvest effort followed closely with seal distribution obtained from aerial surveys. These data could be used as a source of information on seal herd location throughout the breeding and molting seasons and for more complex demographic or life-table models. We did not find any evidence of the decline of catch per unit effort over the study period. Timely introduction of state regulations and efficient harvest management apparently prevented severe depletion of ice-associated seal populations in the Sea of Okhotsk during the periods of their intense exploitation.
[Mh] Termos MeSH primário: Otárias
Focas Verdadeiras
[Mh] Termos MeSH secundário: Distribuição Animal
Animais
Gelo
População
Federação Russa
Estações do Ano
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ice)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182725


  9 / 2162 MEDLINE  
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[PMID]:28796829
[Au] Autor:Zappes IA; Fabiani A; Sbordoni V; Rakaj A; Palozzi R; Allegrucci G
[Ad] Endereço:Department of Biology, University of Rome Tor Vergata, Rome, Lazio, Italy.
[Ti] Título:New data on Weddell seal (Leptonychotes weddellii) colonies: A genetic analysis of a top predator from the Ross Sea, Antarctica.
[So] Source:PLoS One;12(8):e0182922, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this paper, we studied the genetic variability in Weddell seal from colonies in Terra Nova Bay and Wood Bay, both sites located in the Ross Sea area, Antarctica. Two mitochondrial genes and one nuclear gene, with different mutation rates, were sequenced to investigate the haplotype diversity of the colonies and to test for a possible recent expansion. Fifteen microsatellites were used to analyze their genetic structure. Sequenced genes and microsatellites were also used to estimate the effective population size of the studied colonies and the Ross Sea seal population. The Ross Sea has a high density population of Weddel seals, with an estimated effective number of 50,000 females, and 1,341 individuals for the sampling area, possibly due to its high primary production. The colonies showed high diversity (Hd > 0.90) and many exclusive haplotypes (> 75%), likely a consequence of the surprisingly high site fidelity of Weddell seals, despite the proximity of the colonies. Nevertheless, there was low microsatellite differentiation between colonies, suggesting that they are part of a single larger population. Their expansion seemed to have started during the last glacial cycle (around 58,000 years ago), indicating that the Ross Sea seal populations have been present in the area for long time, probably due to the lack of hunting by humans and terrestrial predation. As a top predator, the role of Weddell seals in the Ross Sea ecology is crucial, and its demographic dynamics should be monitored to follow the future changes of such an important ecosystem.
[Mh] Termos MeSH primário: Focas Verdadeiras/genética
[Mh] Termos MeSH secundário: Animais
Regiões Antárticas
DNA Mitocondrial/genética
Ecossistema
Feminino
Variação Genética
Haplótipos
Masculino
Repetições de Microssatélites
Densidade Demográfica
Comportamento Predatório
Focas Verdadeiras/fisiologia
Cromossomo Y/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Mitochondrial)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182922


  10 / 2162 MEDLINE  
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[PMID]:28732330
[Au] Autor:Corsolini S; Ademollo N; Martellini T; Randazzo D; Vacchi M; Cincinelli A
[Ad] Endereço:University of Siena, Department of Physics, Earth and Environmental Sciences, Via Mattioli, 4, 53100 Siena, Italy. Electronic address: simonetta.corsolini@unisi.it.
[Ti] Título:Legacy persistent organic pollutants including PBDEs in the trophic web of the Ross Sea (Antarctica).
[So] Source:Chemosphere;185:699-708, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The ecological features of the Ross Sea trophic web are peculiar and different from other polar food webs, with respect to the use of habitat and species interactions; due to its ecosystem integrity, it is the world's largest Marine Protected Area, established in 2016. Polar organisms are reported to bioaccumulate lipophilic contaminant, viz persistent organic pollutants (POPs). Legacy POPs and flame retardants (polybrominated diphenyl ethers, PBDEs) were studied in key species of the Ross Sea (Euphausia superba, Pleuragramma antarctica) and their predators (Dissostichus mawsoni, Pygoscelis adeliae, Aptenodytes forsteri, Catharacta maccormicki, Leptonychotes weddellii). Gaschromatography revealed the presence of PCBs, HCB, DDTs, PBDEs in most of the samples; HCHs, dieldrin, Eldrin, non-ortho PCBs, PCDDs, PCDFs were detected only in some species. The average ∑PBDEs was 0.19-1.35 pg/g wet wt in the key-species and one-two order of magnitude higher in the predators. Penguins and skuas from an area where a long-term field camp is located showed higher BDE concentrations. The ΣDDTs was higher in the Antarctic toothfish (20 ± 6.73 ng/g wet wt) and in the South Polar skua (5.911 ± 3.425 ng/g wet wt). The TEQs were evaluated and the highest concentration was found in the Weddell seal, due to PCB169, 1,2,3,4,7,8-HxCDF, and 2,3,4,6,7,8-HxCDF. There was no significant relationship between the trophic level and the POP concentrations. Although low concentrations, organisms of the Ross Sea trophic web should be further studied: lack of information on some ecotoxicological features and human impacts including global change may distress the ecosystem with unpredictable effects.
[Mh] Termos MeSH primário: Monitoramento Ambiental
Cadeia Alimentar
Éteres Difenil Halogenados/análise
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Animais
Regiões Antárticas
Charadriiformes
Peixes
Retardadores de Chama/análise
Éteres Difenil Halogenados/metabolismo
Bifenilos Policlorados/análise
Bifenilos Policlorados/metabolismo
Focas Verdadeiras
Spheniscidae
Poluentes Químicos da Água/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Flame Retardants); 0 (Halogenated Diphenyl Ethers); 0 (Water Pollutants, Chemical); DFC2HB4I0K (Polychlorinated Biphenyls); T2P1WH546D (3,4,5,3',4',5'-hexachlorobiphenyl)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170722
[St] Status:MEDLINE



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