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1.
Mol Ecol ; 30(13): 3158-3174, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33481325

RESUMO

Environmental DNA (eDNA) metabarcoding can rapidly characterize the composition and diversity of benthic communities, thus it has high potential utility for routine assessments of benthic impacts of marine finfish farming. In this study, 126 sediment grab samples from 42 stations were collected at six salmon farms in British Columbia, Canada. Benthic community changes were assessed by both eDNA metabarcoding of metazoans and macrofaunal polychaete surveys. The latter was done by analysing 11,466 individuals using a combination of morphology-based taxonomy and DNA barcoding. Study objectives were to: (i) compare biotic signals associated with benthic impacts of salmon farming in the two data sources, and (ii) identify potential eDNA indicators to facilitate monitoring in Canada. Alpha diversity parameters were consistently reduced near fish cage edge and negatively correlated with pore-water sulphide concentration, with coefficients ranging from -0.62 to -0.48. Although Polychaeta are a common indicator group, the negative correlation with pore-water sulphide concentration was much stronger for Nematoda OTU richness (correlation coefficient: -0.86) than for Polychaeta (correlation coefficient: -0.38). Presence/absence of Capitella generally agreed well between the two methods despite that they differed in the volume of sediments sampled and the molecular marker used. Multiple approaches were used to identify OTUs related to organic enrichment statuses. We demonstrate that eDNA metabarcoding generates biotic signals that could be leveraged for environmental assessment of benthic impacts of fish farms in multiple ways: both alpha diversity and Nematoda OTU richness could be used to assess the spatial extent of impact, and OTUs related to organic enrichment could be used to develop local biotic indices.


Assuntos
Código de Barras de DNA Taxonômico , Salmão , Animais , Aquicultura , Biodiversidade , Colúmbia Britânica , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Salmão/genética
2.
Dis Aquat Organ ; 125(1): 79-84, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28627495

RESUMO

During the fall of 2015, up to 40% mortality occurred in juvenile Yesso scallops Patinopecten yessoensis at an aquaculture site in Baynes Sound, British Columbia, Canada. Macroscopic lesions were present in 11% of the scallops, and histopathology consisting of multifocal and diffuse haemocyte infiltration was observed in 44% of the specimens examined. Histologically, small Gram-negative intracellular bacteria-like particles were observed within necrotic haemocytes of the lesions, suggesting a bacterial aetiology. DNA was extracted from adductor muscle lesions of diseased scallops, and the 16s rDNA gene as well as the DNA-directed RNA polymerase beta subunit (rpoB) were amplified by PCR. Sequence analyses of the resulting 413 and 925 bp fragments were a 100% match to the reference sequence for Francisella halioticida, originally described as the cause of mortality in abalone from Japan. Isolation and culture of the bacteria was not possible at the time, as no further diseased specimens were available. Results from in situ hybridization assays as well as examination by transmission electron microscopy provide further evidence supporting the hypothesis that F. halioticida was the most probable causative agent of the lesions and mortality.


Assuntos
Francisella/fisiologia , Pectinidae/microbiologia , Animais , Interações Hospedeiro-Patógeno
3.
PeerJ ; 10: e13191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573171

RESUMO

Orchids often have specific pollinators, which should provide reproductive isolation, yet many produce natural hybrids. Platanthera dilatata and P. stricta differ in floral morphology but often co-occur, overlap in flowering, and are reputed parents of P. xestesii. We used motion-triggered video detection units to monitor floral visitors of P. dilatata and P. stricta on Vancouver Island, Canada. Pollinia removal in P. dilatata was observed using histochemical staining, and cross-pollinations were performed to determine compatibility. From 1,152 h, 753 videos were recorded; 655 contained insects and 91 contained arachnids. Bumblebees, butterflies, and moths removed pollinia from P. dilatata. No pollinia removal was observed from P. stricta. Five videos showed insects moving between Platanthera species. Pollinia removal rates were low. Hand-pollinations resulted in capsule development and seed production. This study adds to the known diversity of insects interacting with these orchids, and highlights regional differences in floral visitors.


Assuntos
Borboletas , Orchidaceae , Animais , Flores/anatomia & histologia , Insetos , Polinização
4.
Biodivers Data J ; 10: e76050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437414

RESUMO

Background: Based on records dating from 1859 to 2021, we provide an overview of the marine animal diversity reported for Galiano Island, British Columbia, Canada. More than 650 taxa are represented by 20,000 species occurrence records in this curated dataset, which includes dive records documented through the Pacific Marine Life Surveys, museum voucher specimens, ecological data and crowd-sourced observations from the BC Cetacean Sightings Network and iNaturalist. New information: We describe Galiano Island's marine animal diversity in relation to the Salish Sea's overall biodiversity and quantify the proportional contributions of different types of sampling effort to our current local knowledge. Overviews are provided for each taxonomic group in a format intended to be accessible to amateur naturalists interested in furthering research into the region's marine biodiversity. In summary, we find that the Pacific Marine Life Surveys, a regional community science diving initiative, account for 60% of novel records reported for Galiano Island. Voucher specimens account for 19% and crowd-sourced biodiversity data 18% of novel records, respectively, with the remaining 3% of reports coming from other sources. These findings shed light on the complementarity of different types of sampling effort and demonstrate the potential for community science to contribute to the global biodiversity research community. We present a biodiversity informatics framework that is designed to enable these practices by supporting collaboration among researchers and communities in the collection, curation and dissemination of biodiversity data.

5.
Nature ; 436(7052): 866-70, 2005 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16007076

RESUMO

Assimilation of carbon by plants incurs water costs. In the many parts of the world where water is in short supply, plant transpiration efficiency, the ratio of carbon fixation to water loss, is critical to plant survival, crop yield and vegetation dynamics. When challenged by variations in their environment, plants often seem to coordinate photosynthesis and transpiration, but significant genetic variation in transpiration efficiency has been identified both between and within species. This has allowed plant breeders to develop effective selection programmes for the improved transpiration efficiency of crops, after it was demonstrated that carbon isotopic discrimination, Delta, of plant matter was a reliable and sensitive marker negatively related to variation in transpiration efficiency. However, little is known of the genetic controls of transpiration efficiency. Here we report the isolation of a gene that regulates transpiration efficiency, ERECTA. We show that ERECTA, a putative leucine-rich repeat receptor-like kinase (LRR-RLK) known for its effects on inflorescence development, is a major contributor to a locus for Delta on Arabidopsis chromosome 2. Mechanisms include, but are not limited to, effects on stomatal density, epidermal cell expansion, mesophyll cell proliferation and cell-cell contact.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Transpiração Vegetal/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Carbono/metabolismo , Isótopos de Carbono , Dessecação , Desastres , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Genótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Transpiração Vegetal/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Água/farmacologia
6.
Dis Aquat Organ ; 93(3): 243-50, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21516977

RESUMO

Mikrocytos mackini is a microcell parasite of Pacific oysters only known to occur on the Pacific coast of North America. It is the only described species in the genus, although a genetically divergent Mikrocytos sp. organism has been reported once in both the Atlantic Ocean and China. We developed methods for sequencing the internal transcribed spacer (ITS) of rDNA for the purpose of characterizing extant diversity within M. mackini throughout its known geographic range, and surveying for other evidence of Mikrocytos sp. organisms. Our specific aims were to examine relatedness of M. mackini among sites to make inferences about its recent evolutionary history, and to provide baseline data for future development of a species-specific molecular detection method. We found a total lack of genetic variation within M. mackini across the complete ITS1-5.8S-ITS2 array in over 70 samples collected throughout its range. We hypothesize that this could be a result of a founder effect if the parasite had been introduced into its known range alongside its host, which was imported from Asia beginning around 1914 to about 1961. We detected a single divergent sequence at a short stretch of 18S that was identical to the Mikrocytos sp. detected elsewhere, which adds to the recent and growing body of evidence that Mikrocytos is much more broadly distributed than the limited range of M. mackini suggests. A 1903 bp section of rDNA from Mikrocytos sp. was generated that contained regions of high divergence from M. mackini (in ITS1 and ITS2) that could be exploited for molecular diagnostics.


Assuntos
DNA Espaçador Ribossômico/genética , Ostreidae/parasitologia , Parasitos/genética , Animais , Sequência de Bases , Variação Genética , Interações Hospedeiro-Parasita , Reação em Cadeia da Polimerase
7.
JMIR Public Health Surveill ; 6(3): e19969, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32501806

RESUMO

BACKGROUND: In the absence of vaccines and established treatments, nonpharmaceutical interventions (NPIs) are fundamental tools to control coronavirus disease (COVID-19) transmission. NPIs require public interest to be successful. In the United States, there is a lack of published research on the factors that influence public interest in COVID-19. Using Google Trends, we examined the US level of public interest in COVID-19 and how it correlated to testing and with other countries. OBJECTIVE: The aim of this study was to determine how public interest in COVID-19 in the United States changed over time and the key factors that drove this change, such as testing. US public interest in COVID-19 was compared to that in countries that have been more successful in their containment and mitigation strategies. METHODS: In this retrospective study, Google Trends was used to analyze the volume of internet searches within the United States relating to COVID-19, focusing on dates between December 31, 2019, and March 24, 2020. The volume of internet searches related to COVID-19 was compared to that in other countries. RESULTS: Throughout January and February 2020, there was limited search interest in COVID-19 within the United States. Interest declined for the first 21 days of February. A similar decline was seen in geographical regions that were later found to be experiencing undetected community transmission in February. Between March 9 and March 12, 2020, there was a rapid rise in search interest. This rise in search interest was positively correlated with the rise of positive tests for SARS-CoV-2 (6.3, 95% CI -2.9 to 9.7; P<.001). Within the United States, it took 52 days for search interest to rise substantially after the first positive case; in countries with more successful outbreak control, search interest rose in less than 15 days. CONCLUSIONS: Containment and mitigation strategies require public interest to be successful. The initial level of COVID-19 public interest in the United States was limited and even decreased during a time when containment and mitigation strategies were being established. A lack of public interest in COVID-19 existed in the United States when containment and mitigation policies were in place. Based on our analysis, it is clear that US policy makers need to develop novel methods of communicating COVID-19 public health initiatives.


Assuntos
Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Opinião Pública , Ferramenta de Busca/tendências , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Comparação Transcultural , Humanos , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia
8.
J Parasitol ; 99(2): 183-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23088449

RESUMO

Gyrodactylus leptorhynchi n. sp. (Monogenea) is described from bay pipefish ( Syngnathus leptorhynchus ) (Syngnathidae) in coastal waters of southern California and British Columbia, and from an outbreak of gyrodactylosis at the Cabrillo Marine Aquarium in California. Gyrodactylus leptorhynchi is morphologically similar (stout hamuli, superficial bar with no anterolateral processes, and a small, triangular membrane, similarly shaped marginal hook sickles, and a male copulatory organ [MCO] with numerous small spines) to the other 6 species of Gyrodactylus known from pipefish in north and south regions of the Atlantic Ocean. It resembles most closely Gyrodactylus corleonis Paladini, Cable, Fioravanti, Faria, and Shinn, 2010 , parasitizing Syngnathus typhle L. from the French Mediterranean in having relatively large hamuli (58 µm). However, in G. leptorhynchi, the marginal hook sickle has a reduced heel and a ledged toe, while in G. corleonis, it has a noticeable heel and a toe with no distinct ledge. DNA sequence data of a partial ITS1 (700+ bp), complete 5.8S (157 bp), complete ITS2 (392 bp), and a partial 18S (441 bp) are included in the description; the data are distinct from those available for other species of Gyrodactylus. The molecular data reveal that G. leptorhynchi is a member of a basal lineage of marine species within Gyrodactylus sensu lato that is known to have radiated among coastal syngnathid, anguillid, and gobiid fishes throughout the Atlantic Ocean and some adjacent waters. Occurrence of G. leptorhynchi in the eastern Pacific supports the idea that such lineages may have global distributions. Sixty-three percent (15 of 24) of bay pipefish caught at Inner Cabrillo Beach, California, were infected with 1-3 worms, predominately located on the dorsal fin, but also on the anterior body surfaces. Intensely infected pipefish at the marine aquarium had parasites distributed all over the body surface, including the open edge of the brood pouch and, on 2 occasions, inside the brood pouch. A quarantine protocol, involving the treatment of wild pipefish with serial repeats of topical anthelmintic chemicals (formalin, Trichlorfon, and Praziquantel), that helps to diminish outbreaks of G. leptorhynchi in aquarium exhibits is described.


Assuntos
Doenças dos Peixes/parasitologia , Platelmintos/classificação , Smegmamorpha/parasitologia , Infecções por Trematódeos/veterinária , Administração Tópica , Animais , Anti-Helmínticos/administração & dosagem , Sequência de Bases , Colúmbia Britânica , California , DNA de Helmintos/química , Doenças dos Peixes/tratamento farmacológico , Formaldeído/administração & dosagem , Masculino , Dados de Sequência Molecular , Oceano Pacífico , Platelmintos/anatomia & histologia , Platelmintos/genética , Praziquantel/administração & dosagem , Infecções por Trematódeos/tratamento farmacológico , Infecções por Trematódeos/parasitologia , Triclorfon/administração & dosagem
9.
J Parasitol ; 96(4): 681-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20738197

RESUMO

Gyrocerviceanseris passamaquoddyensis n. gen., n. sp. is described from the gills of silver hake, Merluccius bilinearis , in Passamaquoddy Bay, southwestern New Brunswick, Canada. Diagnostic features include an oval haptor with asymmetrically distributed marginal hooks (3 pairs anterior, 5 pairs posterior) and a prominent muscular flange on the lateral margins, between the anterior and posterior groups of hooks. The hamuli are well developed, with a straight point, a short shaft, and an elongate, blade-like ventral root having a ventrally directed, gooseneck-shaped tip. The ventral bar is rectangular, with a small, hourglass-shaped posterior membrane. There is no dorsal bar. The marginal hook sickle is sharply curved, with a long fine point, an upturned toe, a small heel, and a straight handle. A partial DNA sequence from 18S rDNA was generated and found to be over 11% divergent from its closest matches in GenBank. However, it was less divergent (7.8%) from a previously unpublished sequence of Gyrodactylus emembranatus Malmberg, 1970 , suggesting this species is its closest known relative. Interestingly, both species have almost identical marginal hook sickles and a male copulatory organ (MCO) with small spines in multiple arched rows. Gyrocerviceanseris n. gen. is the sixth genus of viviparous monogeneans to be described from marine and estuarine fishes of the northwestern Atlantic Ocean.


Assuntos
Doenças dos Peixes/parasitologia , Gadiformes/parasitologia , Platelmintos/classificação , Infecções por Trematódeos/veterinária , Animais , DNA de Helmintos/química , Brânquias/parasitologia , Novo Brunswick , Platelmintos/anatomia & histologia , Platelmintos/genética , Água do Mar , Infecções por Trematódeos/parasitologia
10.
Mol Ecol Resour ; 9 Suppl s1: 90-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564969

RESUMO

Using data from published mitochondrial or complete genomes, we developed and tested primers for amplification and sequencing of the barcode region of cytochrome oxidase 1 (COX1) of the fungal genus Fusarium, related genera of the order Hypocreales, and degenerate primers for fungi in the subdivision Pezizomycotina. The primers were successful for amplifying and sequencing COX1 barcodes from 13 genera of Hypocreales (Acremonium, Beauveria, Clonostachys, Emericellopsis, Fusarium, Gliocladium, Hypocrea, Lanatonectria, Lecanicillium, Metarhizium, Monocillium, Neonectria and Stilbella), 22 taxa of Fusarium, and two genera in other orders (Arthrosporium, Monilochaetes). Parologous copies of COX1 occurred in several strains of Fusarium. In some, copies of the same length were detected either by heterozygous bases in otherwise clean sequences or in different replicates of amplification and sequencing events; this may indicate multiple transcribed copies. Other strains included one or two introns. Two intron insertion sites had at least two nonhomologous intron sequences among Fusarium species. Irrespective of whether the multiple copy issue could be resolved by sequencing RNA transcripts, developing a precise COX1-based barcoding system for Fusarium may not be feasible. The overall divergence among homologous COX1 sequences obtained so far is rather low, with many species sharing identical sequences.

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