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1.
Zoo Biol ; 40(4): 273-279, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33848361

RESUMEN

Vancouver Island marmots (Marmota vancouverensis) have been managed in a captive-breeding program since 1997, as in situ conservation efforts were insufficient in raising the numbers of this critically endangered species. The success of captive-breeding programs centers on sustainable reproduction and survival of individuals once released into the wild. Captive-born Vancouver Island marmots released to the wild have lower survival rates than their wild-born counterparts; this difference may arise from compromised hibernation patterns or behaviors. Hibernation duration, body weight over the hibernation season, and reproductive success of captive Vancouver Island marmots were reviewed to assess the effect of these variables on each other. Data from a total of 1782 hibernations and 456 breeding attempts were compiled from 1997 to 2018. The number of winters spent in captivity, the origin of the marmot (captive-born or wild-born), the facility at which hibernation occurred, and the body weight all had a significant effect on hibernation length (all p < .001). Increased weight was associated with increased hibernation length by 0.4 ± 0.1 day/kg on average (p = .0015). Captive, wild-born marmots hibernated for significantly longer than their captive-born counterparts by about 21 ± 2 days (p < .001). The odds of successful breeding were significantly increased with increasing hibernation length by approximatively 20% for every 10 additional days of hibernation. This study provides information on the intrinsic relationship between body weight, reproduction, and hibernation in captive Vancouver Island marmots.


Asunto(s)
Crianza de Animales Domésticos , Animales de Zoológico , Hibernación/fisiología , Marmota/fisiología , Reproducción/fisiología , Animales , Femenino , Masculino , Estudios Retrospectivos
2.
Emerg Infect Dis ; 25(9): 1723-1726, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31441746

RESUMEN

We compared 2 climate classification systems describing georeferenced environmental Cryptococcus gattii sensu lato isolations occurring during 1989-2016. Each system suggests the fungus was isolated in temperate climates before the 1999 outbreak on Vancouver Island, British Columbia, Canada. However, the Köppen-Geiger system is more precise and should be used to define climates where pathogens are detected.


Asunto(s)
Clima , Criptococosis/epidemiología , Cryptococcus gattii/aislamiento & purificación , Brotes de Enfermedades , Colombia Británica/epidemiología , Criptococosis/microbiología , Cryptococcus gattii/clasificación , Humanos , Islas , Microbiología del Suelo
3.
J Infect Chemother ; 24(7): 573-575, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29352650

RESUMEN

A 71-year-old Japanese man with travel history to the Vancouver Island, Canada was diagnosed the pulmonary and central nervous system infections caused by Cryptococcus gattii genotype VGIIa. This is the first imported case of Cryptococcus gattii genotype VGIIa infection from endemic area of North America to Japan. He was recovery with no residual neurological dysfunction by early resection of brain mass and antifungal therapy. Early surgical resection of cerebellar cryptococcoma may shorten the length of induction therapy with antifungal drugs.


Asunto(s)
Infecciones Fúngicas del Sistema Nervioso Central/microbiología , Criptococosis/microbiología , Cryptococcus gattii/genética , Enfermedades Pulmonares Fúngicas/microbiología , Anciano , Antifúngicos/uso terapéutico , Antígenos Fúngicos/sangre , Antígenos Fúngicos/líquido cefalorraquídeo , Canadá , Infecciones Fúngicas del Sistema Nervioso Central/tratamiento farmacológico , Infecciones Fúngicas del Sistema Nervioso Central/cirugía , Angiografía por Tomografía Computarizada , Criptococosis/tratamiento farmacológico , Cryptococcus gattii/clasificación , Cryptococcus gattii/aislamiento & purificación , Genotipo , Humanos , Japón , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Imagen por Resonancia Magnética , Masculino , Tipificación de Secuencias Multilocus , Radiografía , Análisis de Secuencia de ADN
4.
J Zoo Wildl Med ; 49(2): 484-488, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29900789

RESUMEN

A 2-mo-old Vancouver Island marmot ( Marmota vancouverensis), housed at a quarantined breeding facility, presented for acute obtundation and vestibular ataxia. Physical examination revealed poor growth compared with littermates, poor nutritional condition, and mild dehydration. The animal's condition deteriorated over 24 hr, and it was euthanized following the development of generalized seizures. No gross abnormalities were observed upon postmortem evaluation. Histologic evaluation revealed severe, multifocal, granulomatous and lymphoplasmacytic meningoencephalomyelitis and interstitial nephritis, with intralesional, intracytoplasmic spore-filled, parasitophorous vacuoles and segmental, multi-organ, fibrinoid vasculitis (disseminated encephalitozoonosis). The etiologic agent was evident by hematoxylin and eosin and Gram-chromotrope stains, and confirmed as Encephalitozoon cuniculi by polymerase chain reaction on brain tissue. Sequencing of the internal transcribed spacer region of the rRNA gene showed 100% homology with E. cuniculi strain IV, which is a newly described genotype. This is the first report of encephalitozoonosis in this critically endangered species.


Asunto(s)
Encephalitozoon cuniculi/aislamiento & purificación , Encefalitozoonosis/veterinaria , Marmota , Enfermedades de los Roedores/patología , Animales , Animales de Zoológico , Colombia Británica , Encephalitozoon cuniculi/clasificación , Encefalitozoonosis/parasitología , Encefalitozoonosis/patología , Especies en Peligro de Extinción , Resultado Fatal , Masculino , Enfermedades de los Roedores/parasitología
5.
Emerg Infect Dis ; 21(11): 1989-96, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26484590

RESUMEN

Vancouver Island, Canada, reports the world's highest incidence of Cryptococcus gattii infection among humans and animals. To identify key biophysical factors modulating environmental concentrations, we evaluated monthly concentrations of C. gatti in air, soil, and trees over a 3-year period. The 2 study datasets were repeatedly measured plots and newly sampled plots. We used hierarchical generalized linear and mixed effect models to determine associations. Climate systematically influenced C. gattii concentrations in all environmental media tested; in soil and on trees, concentrations decreased when temperatures were warmer. Wind may be a key process that transferred C. gattii from soil into air and onto trees. C. gattii results for tree and air samples were more likely to be positive during periods of higher solar radiation. These results improve the understanding of the places and periods with the greatest C. gattii colonization. Refined risk projections may help susceptible persons avoid activities that disturb the topsoil during relatively cool summer days.


Asunto(s)
Cryptococcus gattii/clasificación , Microbiología del Aire , Colombia Británica , Criptococosis , Cryptococcus gattii/genética , Cryptococcus gattii/crecimiento & desarrollo , Humanos , Islas , Microbiología del Suelo , Árboles/microbiología
6.
Animals (Basel) ; 14(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38338030

RESUMEN

The Vancouver Island marmot (Marmota vancouverensis) is Canada's most endangered endemic mammal. In 1997, a conservation breeding-for-release program was established to supplement wild marmot populations. Retrospective analyses of captive breeding studbook records since 2000 indicate the age of the sire and the dam significantly impacted the odds of successfully weaning a litter. Dams and sires between 5 and 7 years of age had more than double the odds of reproductive success compared to older animals. Successful reproduction by the dam in the previous year also doubled the odds of successfully weaning a litter in subsequent years. Assessment of adrenal function via fecal glucocorticoid analyses indicated established breeding pairs had decreased stress compared to new pairs (5.74 ± 0.28 ng/g vs. 7.60 ± 0.34 ng/g; p < 0.0001). Pairs that were ultimately successful at weaning pups in a breeding season had decreased stress compared to unsuccessful pairs (6.05 ± 0.34 ng/g vs. 7.22 ± 0.28 ng/g; p = 0.0006). These endocrine results suggest social buffering via familiarity and breeding/pair bond formation may be decreasing stress in established and successful pairs, respectively. The results of this study will be used to assist in the captive breeding management of this species to optimise numbers of animals produced to supplement the wild populations.

7.
Conserv Physiol ; 11(1): coad041, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38026799

RESUMEN

Conservation breeding programs typically involve the management of individuals both in and ex situ, so it is vital to understand how the physiology of managed species changes in these environments to maximize program outcomes. The Vancouver Island marmot (VIM; Marmota vancouverensis) is one species that has been managed in a conservation breeding program to recover the critically low wild population. Previous research has shown there are differences in hair glucocorticoid concentrations for VIMs in different managed groups in the program. Therefore, we used >1000 blood samples collected since the program's inception to assess the neutrophil to lymphocyte (N:L) ratio among captive, pre-release, post-release and wild populations as another metric of stress. In situ VIM populations were found to have a significantly higher N:L ratio than ex situ populations, suggesting that the wild is a more physiologically challenging environment than managed care. Moreover, the effect of age, sex and the month of sampling on the N:L ratio were found to be different for each population. Age had the greatest magnitude of effect in the wild population, and sex was only significant in ex situ populations. This study provided previously unknown insights into the physiology of VIMs and increased post-release monitoring will be useful in the future to fully understand how physiology may be contributing to differences in survival of VIMs in the program.

8.
Harmful Algae ; 129: 102530, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37951625

RESUMEN

Domoic acid, a phycotoxin produced by species of the marine diatom Pseudo-nitzschia, can cause deleterious impacts to marine food webs and human health. Domoic acid and Pseudo-nitzschia spp. were surveyed from 2016 to 2021 in the Pacific waters of Canada to assess their occurrences, concentrations, and relationships with physical and chemical conditions. Domoic acid was common, occurring in measurable concentrations in 73 % of the 454 samples. It occurred in all regions (west coast of Vancouver Island, Salish Sea, Queen Charlotte Sound / Hecate Strait, deep oceanic NE Pacific), in all years and all seasons. Median concentrations were highest along the west coast of Vancouver Island, and lowest in the oceanic waters of the NE Pacific. Winter had the lowest concentrations; no significant differences occurred between spring, summer, and autumn. High domoic acid concentrations equal to or above 100 ng/L were not common, occurring in about 5 % of samples, but in all seasons and all years except 2019. All six Pseudo-nitzschia taxa identified had similar median concentrations, but different frequencies of occurrence. P. cf. australis appeared to be the major contributor to high concentrations of domoic acid. Physico-chemical conditions were described by ten variables: temperature, salinity, density difference between 30 m and the surface (a proxy for vertical stability), chlorophyll a, nitrate, phosphate, silicate, and the ratios nitrate:phosphate, nitrate:silicate, and silicate:phosphate. Statistical analyses, using general linear models, of their relationships with the absence/presence of Pseudo-nitzschia spp. found silicate (negative) to be the most influential variable common in both the west coast of Vancouver Island and Salish Sea regions. Temperature and chlorophyll a were the most influential variables which determined the log10 abundance of Pseudo-nitzschia spp. in both regions. Analyses of the absence/presence of particulate domoic acid per Pseudo-nitzschia cell (excluding P. americana) found chlorophyll a to be the most influential variable common in both regions, whereas no common influential variable determined the log10 concentration of particulate domoic acid per Pseudo-nitzschia cell (excluding P. americana). These results were generally similar to those of other studies from this area, although this study extends these findings to all seasons and all regions of Canada's Pacific waters. The results provide important background information against which major outbreaks and unusual events can be compared. A domoic acid surveillance program during synoptic oceanographic surveys can help to understand where and when it reaches high concentrations at sea and the potential impacts to the marine ecosystem.


Asunto(s)
Diatomeas , Nitratos , Humanos , Canadá , Clorofila A , Ecosistema , Fosfatos , Silicatos
9.
Geobiology ; 19(5): 521-541, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33960615

RESUMEN

Marine oxygen minimum zones play a crucial role in the global oceanic carbon, nitrogen, and sulfur cycles as they harbor microbial communities that are adapted to the water column chemistry and redox zonation, and in turn control the water column chemistry and greenhouse gas release. These micro-organisms have metabolisms that rely on terminal electron acceptors other than O2 and often benefit from syntrophic relationships (metabolic coupling). Here, we study chemo(auto)trophy along the redoxcline in two stratified fjords on Vancouver Island (Canada) using bacterial bacteriohopanepolyols and archaeal ether lipids. We analyze the distribution of these lipid classes in suspended particulate matter (SPM) to trace ammonia oxidation, anaerobic ammonium oxidation (anammox), sulfate reduction/sulfur oxidation, methanogenesis, and methane oxidation, and investigate ecological niches to evaluate potential links between their respective bacterial and archaeal sources. Our results show an unparalleled BHP and ether lipid structural diversity that allows tracing the major redox-driven metabolic processes at the time of sampling: Both fjords are dominated by archaeal ammonia oxidation and anammox; sulfate-reducing bacteria may be present in Deer Bay, but absent from Effingham Inlet; methanogenic Euryarchaeota and archaeal and bacterial methanotrophs are detectable at low abundance. Correlation analysis reveals distinct biomarker clusters that provide constraints on the biogeochemical niches of some orphan BHP and ether lipids such as in situ-produced adenosyl-BHPs or unsaturated archaeols.


Asunto(s)
Ciervos , Microbiota , Animales , Archaea , Bacterias , Estuarios , Lípidos , Oxidación-Reducción , Filogenia
10.
Environ Pollut ; 244: 135-142, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30321708

RESUMEN

Microplastics are a significant issue in the world's oceans. These small plastic particles (<5 mm in size) are becoming globally ubiquitous in the marine environment and are ingested by various fish species. Here we investigate the incidence of microplastics in juvenile Chinook salmon and their nearshore marine environments on the east coast of Vancouver Island, British Columbia. We completed a series of beach seines, plankton tows and sediment cores in nearshore areas of importance to juvenile salmon. Microplastics were extracted from fish, water and sediment samples and concentrations were quantified. Microplastics analysis, consisting predominantly of fibrous plastics, showed juvenile Chinook salmon contained 1.2 ±â€¯1.4 (SD) microplastics per individual while water and sediment samples had 659.9 ±â€¯520.9 microplastics m-3 and 60.2 ±â€¯63.4 microplastics kg-1 dry weight, respectively. We found no differences in microplastic concentrations in juvenile Chinook and water samples among sites but observed significantly higher concentrations in sediment at the Deep Bay site compared to Nanaimo and Cowichan Bay sites. Chinook microplastic concentrations were relatively low compared to literature values and, given the size and type of microplastics we observed, are unlikely to represent an immediate threat to fish in this area. However, microplastics less than 100 µm in size were not included in the study and may represent a greater threat due to their ability to translocate through tissues.


Asunto(s)
Tracto Gastrointestinal/química , Sedimentos Geológicos/análisis , Plásticos/análisis , Salmón , Agua de Mar/análisis , Animales , Colombia Británica , Monitoreo del Ambiente , Contaminantes del Agua/análisis
11.
Conserv Physiol ; 6(1): coy037, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30018762

RESUMEN

Hair cortisol analysis has been used to quantify hormone levels in circulation in several mammal species. Hair remains stable for decades or centuries, allowing researchers to use archived hair samples to investigate hormone levels that span long time periods. However, several studies have found that intra-individual variability, driven by the body region from which a sample is derived, confounds measurements of systemic glucocorticoid hormone concentrations. In addition, the external application of chemical agents to hair can remove or concentrate molecules of interest. These may preclude the use of samples that have been collected opportunistically and/or those that have been housed in museum collections. Using a captive population of Vancouver Island marmots (Marmota vancouverensis), we found a strong effect of body region on the concentration of cortisol within hair, as well as an effect of season. Using a collection of American mink (Neovison vison) pelts, we found that application of the preservative arsenic in the form of a soap does not cause a significant decrease in cortisol. The marmot results suggest that intra-individual variability is not stable through time. The reason for these seasonal effects is not clear and further study is necessary. Researchers using samples from an unknown body region should exercise caution in interpreting their results. The mink results suggest that samples held in museum collections can be used to quantify cortisol, even when arsenic preservation is suspected.

12.
Mar Pollut Bull ; 132: 44-51, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28916350

RESUMEN

The abundance of marine macro-debris was quantified with high spatial resolution by applying an image processing technique to archived shoreline aerial photographs taken over Vancouver Island, Canada. The photographs taken from an airplane at oblique angles were processed by projective transformation for georeferencing, where five reference points were defined by comparing aerial photographs with satellite images of Google Earth. Thereafter, pixels of marine debris were extracted based on their color differences from the background beaches. The debris abundance can be evaluated by the ratio of an area covered by marine debris to that of the beach (percent cover). The horizontal distribution of percent cover of marine debris was successfully computed from 167 aerial photographs and was significantly related to offshore Ekman flows and winds (leeway drift and Stokes drift). Therefore, the estimated percent cover is useful information to determine priority sites for mitigating adverse impacts across broad areas.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminación del Agua/análisis , Playas , Colombia Británica , Islas , Océano Pacífico , Fotograbar , Movimientos del Agua , Viento
13.
Acta Parasitol ; 62(2): 231-254, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28426426

RESUMEN

Pseudopecoelus mccauleyi n. sp. (Opecoelidae: Opecoelinae) is described from the intestine of the bigfin eelpout, Lycodes cortezianus (Gilbert, 1890) (Perciformes: Zoarcidae), collected at 200-800 m depths in the Northeastern Pacific Ocean off Oregon and Vancouver Island, British Columbia. The new species is distinguished by possessing a unique combination of the following diagnostic characters: vitelline fields that extend to the posterior margin of the ventral sucker; a slender, tubular and sinuous seminal vesicle that extends some distance into the hindbody; an unspecialized, protuberant ventral sucker; a genital pore at pharynx level; lobed to deeply multilobed testes; a lobed ovary; and an egg size of 68-80 µm × 30-46 µm. A single specimen of Podocotyle Dujardin, 1845 (Digenea: Plagioporinae) is also described from the intestine of an individual Coryphaenoides sp. (Gadiformes: Macrouridae) collected at 2,800 m depth off Oregon. A listing of parasites from the bigfin eelpout as well as observations of parasite diversity within relevant hosts are offered, new host and locality records are noted, and a brief discussion of Pseudopecoelus von Wicklen, 1946 in the deep sea is presented taking note of the low level of host specificity recorded (i.e. spp. of Pseudopecoelus are now known to parasitize deep-water fish from at least 20 piscine families). A new dichotomous key to the 39 recognized species of Pseudopecoelus is introduced.


Asunto(s)
Enfermedades de los Peces/parasitología , Perciformes/parasitología , Trematodos/anatomía & histología , Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Animales , Enfermedades de los Peces/epidemiología , Océano Pacífico/epidemiología , Especificidad de la Especie , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/parasitología
14.
J Phycol ; 44(3)2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24376283

RESUMEN

Pseudo-nitzschia-specific PCR primers (PnAll F/R) were designed to amplify a polymorphic region of the internal transcribed spacer 1 (ITS1) from at least 11 Pseudo-nitzschia species. The primers were used to generate environmental clone libraries from Puget Sound, Washington, and Vancouver Island, British Columbia, to confirm that the primers were specific for Pseudo-nitzschia and to determine the extent of ITS1 sequence diversity within individual species. All environmental ITS1 sequences generated with PnAll primers displayed the greatest similarity to known Pseudo-nitzschia ITS1 sequences. The length of cloned ITS1 fragments differed among species but was conserved within a species. Intraspecific genotypes exhibited <3% sequence divergence for seven of the 10 species detected in clone libraries. Several ITS1 genotypes unique to the Pacific Northwest were identified in environmental samples, and other genotypes were more broadly distributed. The Pseudo-nitzschia primers were also used to develop an automated ribosomal intergenic spacer analysis (ARISA) to rapidly identify Pseudo-nitzschia species in environmental samples based on species-specific variation in the length of the targeted ITS1 region. The ARISA peaks were then associated with the environmental clone sequences for Pseudo-nitzschia species. Surveying the genetic composition of communities at both the inter- and intraspecific levels will enhance our understanding of Pseudo-nitzschia bloom dynamics.

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