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Biomarker responses and decreasing contaminant levels in ringed seals (Pusa hispida) from Svalbard, Norway.

https://arctichealth.org/en/permalink/ahliterature85995
Source
J Toxicol Environ Health A. 2008;71(15):1009-18
Publication Type
Article
Date
2008
Author
Wolkers Hans
Krafft Bjørn A
van Bavel Bert
Helgason Lisa B
Lydersen Christian
Kovacs Kit M
Author Affiliation
Norwegian Polar Institute, Tromsø, Norway. Hans.Wolkers@npolar.no
Source
J Toxicol Environ Health A. 2008;71(15):1009-18
Date
2008
Language
English
Publication Type
Article
Keywords
Adipose Tissue - chemistry - metabolism
Animals
Biological Markers - analysis - metabolism
Cytochrome P-450 CYP1A1 - analysis - metabolism
Environmental Monitoring - methods
Gas Chromatography-Mass Spectrometry
Liver - chemistry - metabolism
Male
Microsomes, Liver - chemistry - enzymology
Norway
Phoca - metabolism
Polychlorinated biphenyls - analysis
Water Pollutants, Chemical - analysis - metabolism
Abstract
Blubber was analyzed for a wide range of contaminants from five sub-adult and eight adult male ringed seals sampled in 2004, namely, for polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), toxaphenes, chlordanes, dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenylethers (PBDEs). Contaminant levels were compared to previously sampled animals from the same area, as well as data from literature for other arctic wildlife species from a wide variety of locations. Ringed seals sampled in 2004 showed 50-90% lower levels of legacy contaminants such as PCBs and chlorinated pesticides compared to animals sampled in 1996 of similar age (14 sub-adults and 7 adult males), indicating that the decline of chlorinated contaminants observed during the 1990s in a variety of arctic wildlife species is continuing into the 21st century. The results also indicated that PBDE declined in ringed seals; levels in 2004 were about 70-80% lower than in animals sampled in 1998. This is one of the first observations of reduced exposure to these compounds and might be a first indication that restrictions of production and use of these contaminants have resulted in lower exposures in the Arctic. The PCB pattern shifted toward the less chlorinated (i.e., less persistent) PCBs, especially in adult ringed seals, possibly as a result of reduced overall contaminant exposures and a consequently lower cytochrome P-450 (CYP) induction, which results in a slower metabolism of less persistent PCBs. The overall effect would be relative increases in the lower chlorinated PCBs and a relative decreases in the higher chlorinated PCB. Possibly due to low exposure and consequent low induction levels, ethoxyresorufin O-deethylation (EROD) activity proved to be a poor biomarker for contaminant exposure in ringed seals in the present study. The close negative correlation (r(2) = 70.9%)between EROD activity and percent blubber indicates that CYP might respond to increased bioavailability of the contaminant mixtures when they are mobilized from blubber during periods of reduced food intake.
PubMed ID
18569610 View in PubMed
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Climate change impacts on seals and whales in the North Atlantic Arctic and adjacent shelf seas.

https://arctichealth.org/en/permalink/ahliterature95508
Source
Sci Prog. 2008;91(Pt 2):117-50
Publication Type
Article
Date
2008
Author
Kovacs Kit M
Lydersen Christian
Author Affiliation
Biodiversity Research Group, Norwegian Polar Institute, 9696, Tromsø, Norway. Kit.Kovacs@npolar.no
Source
Sci Prog. 2008;91(Pt 2):117-50
Date
2008
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Atlantic Ocean
Ecosystem
Greenhouse Effect
Ice
Pinnipedia - physiology
Population Dynamics
Whales - physiology
Abstract
In a warmer Arctic, endemic marine mammal species will face extreme levels of habitat change, most notably a dramatic reduction in sea ice. Additionally, the physical environmental changes, including less ice and increased water (and air) temperatures will result in alterations to the forage base of arctic marine mammals, including density and distributional shifts in their prey, as well as potential losses of some of their traditionally favoured fat-rich prey species. In addition they are likely to face increased competition from invasive temperate species, increased predation from species formerly unable to access them in areas of extensive sea ice or simply because the water temperature was restrictive, increased disease risk and perhaps also increased risks from contaminants. Over the coming decades it is also likely that arctic marine mammals will face increased impacts from human traffic and development in previously inaccessible, ice-covered areas. Impacts on ice-associated cetaceans are difficult to predict because the reasons for their affiliation with sea ice are not clearly understood. But, it is certain that ice-breeding seals will have marked, or total, breeding-habitat loss in their traditional breeding areas and will certainly undergo distributional changes and in all probability abundance reductions. If species are fixed in traditional spatial and temporal cycles, and are unable to shift them within decadal time scales, some populations will go extinct. In somewhat longer time frames, species extinctions can also be envisaged.
PubMed ID
18717366 View in PubMed
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Novel terrestrial haul-out behaviour by ringed seals (Pusa hispida) in Svalbard, in association with harbour seals (Phoca vitulina).

https://arctichealth.org/en/permalink/ahliterature297161
Source
Polar Research. 36:1. 7 p.
Publication Type
Article
Date
2017
  1 document  
Author
Lydersen, Christian
Vaquie-Garcia, Jade
Lydersen, Espen
Christensen, Guttorm N.
Kovacs, Kit M.
Source
Polar Research. 36:1. 7 p.
Date
2017
Language
English
Geographic Location
Norway
Publication Type
Article
File Size
1607240
Keywords
Arctic
Ringed seals
Harbour seals
Svalbard
Behavioural plasticity
Climate change
Glacier fronts
Lagoons
Sea ice
Abstract
Ringed seals (Pusa hispida) are the most ice-associated of all Arctic pinnipeds. In the Svalbard area, this species has always given birth, moulted and rested on sea ice. In addition, much of their food has been comprised of ice-associated prey. Recently, ringed seals have been reported to be using terrestrial substrates as a haul-out platform in some fjords on the west coast of Spitsbergen. In many cases the seals involved are harbour seals (Phoca vitulina), which are extending their distribution into new areas within the Svalbard Archipelago and which are being misclassified as ringed seals. However, this study reports that terrestrial haulout by ringed seals is also now taking place on rocks exposed at low tide as well as on the coastline. Recent intrusions of warm Atlantic Water (with associated prey) have extended deep into the fjords of western Spitsbergen, resulting in deteriorated ice conditions for ringed seals and expanded habitat for harbour seals. Over the last decade, ringed seals have become more and more confined in coastal areas to narrow bands in front of tidal glacier fronts where Arctic conditions still prevail. In one lagoon area, ringed seals are hauling out on intertidal mud flats in close association with harbour seals. Land can likely replace sea-ice for many of the ringed seals haul-out needs. However, for the small dry-cold adapted ringed seal pups that are normally born in snow lairs on the sea ice, terrestrial haul-out is unlikely to be a viable solution because of predation and thermoregulatory stress.
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Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.

https://arctichealth.org/en/permalink/ahliterature84091
Source
Vet Parasitol. 2007 Nov 30;150(1-2):6-12
Publication Type
Article
Date
Nov-30-2007
Author
Prestrud Kristin Wear
Asbakk Kjetil
Fuglei Eva
Mørk Torill
Stien Audun
Ropstad Erik
Tryland Morten
Gabrielsen Geir Wing
Lydersen Christian
Kovacs Kit M
Loonen Maarten J J E
Sagerup Kjetil
Oksanen Antti
Author Affiliation
Norwegian School of Veterinary Science (NVH), Section of Arctic Veterinary Medicine, P.O. Box 6204, N-9292 Tromsø, Norway.
Source
Vet Parasitol. 2007 Nov 30;150(1-2):6-12
Date
Nov-30-2007
Language
English
Publication Type
Article
Abstract
Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion of seropositive animals was 43% in arctic foxes, 7% in barnacle geese, and 6% (1 of 17) in walruses. There were no seropositive Svalbard reindeer, sibling voles, glaucous gulls, or kittiwakes. The prevalence in the arctic fox was relatively high compared to previous reports from canid populations. There are no wild felids in Svalbard and domestic cats are prohibited, and the absence of antibodies against T. gondii among the herbivorous Svalbard reindeer and voles indicates that transmission of the parasite by oocysts is not likely to be an important mechanism in the Svalbard ecosystem. Our results suggest that migratory birds, such as the barnacle goose, may be the most important vectors bringing the parasite to Svalbard. In addition to transmission through infected prey and carrion, the age-seroprevalence profile in the fox population suggests that their infection levels are enhanced by vertical transmission.
PubMed ID
17950534 View in PubMed
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Serum chemistry of free-ranging white whales (Delphinapterus leucas) in Svalbard.

https://arctichealth.org/en/permalink/ahliterature81813
Source
Vet Clin Pathol. 2006 Jun;35(2):199-203
Publication Type
Article
Date
Jun-2006
Author
Tryland Morten
Thoresen Stein Istre
Kovacs Kit M
Lydersen Christian
Author Affiliation
Norwegian School of Veterinary Science, Section of Arctic Veterinary Medicine, Tromsø, Norway. morten.tryland@veths.no
Source
Vet Clin Pathol. 2006 Jun;35(2):199-203
Date
Jun-2006
Language
English
Publication Type
Article
Keywords
Animals
Beluga Whale - blood
Blood Chemical Analysis - veterinary
Female
Male
Norway
Abstract
BACKGROUND: Abnormal physiological conditions and diseases can change the concentrations of enzymes, metabolites, and minerals in the body. Serum chemistry information may thus be indicative of a specific disease; interpretation of such information requires knowledge of serum chemistry reference intervals from a seemingly healthy population of the species. OBJECTIVE: The aim of this study was to obtain serum chemistry reference intervals for a population of white whales. METHODS: Blood samples were collected from 21 free-ranging white whales (beluga; Delphinapterus leucas). The whales were live-captured in nets during 1996-2001 in Storfjorden, Van Mijenfjorden, and Van Keulenfjorden (Svalbard, Norway). While the whales were briefly physically restrained, blood was collected from the caudal vein into vacuum tubes without anticoagulant. The blood was left to clot for 4-6 hours before serum was obtained by centrifugation. The serum samples were then kept at -20 degrees C until analysis. Enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase [ALP], creatine kinase, lactate dehydrogenase [LDH], amylase, lipase), metabolites (urea, creatinine, bilirubin, cholesterol, triglycerides, nonesterified fatty acids, glucose), and minerals (calcium, phosphate, magnesium, sodium, potassium, chloride) were analyzed in an Advia 1650 System (Bayer, Tarrytown, NY, USA). Cortisol was analyzed in an Immulite One system (Diagnostic Products Corporation, Los Angeles, CA, USA). The major blood proteins (albumin and globulins) were separated by gel electrophoresis in a Beckman Paragon electrophoresis system (Beckman Coulter, Inc., Fullerton, CA, USA). RESULTS: Serum values for all analytes were reported as median and range, and reference intervals were calculated as 10-90th percentiles. Activities of ALP and LDH and cortisol concentration were higher, and protein and bilirubin concentrations were lower compared with those previously reported for white whales from Canada; remaining results were strikingly similar in these 2 white whale populations. CONCLUSIONS: These data provide valuable serum chemistry reference intervals for future health assessments of white whales in Svalbard and other white whale populations, as well as captive individuals.
PubMed ID
16783713 View in PubMed
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Serum chemistry values for free-ranging ringed seals (Pusa hispida) in Svalbard.

https://arctichealth.org/en/permalink/ahliterature79692
Source
Vet Clin Pathol. 2006 Dec;35(4):405-12
Publication Type
Article
Date
Dec-2006
Author
Tryland Morten
Krafft Bjørn A
Lydersen Christian
Kovacs Kit M
Thoresen Stein Istre
Author Affiliation
Department of Food Safety and Infection Biology, Section of Arctic Veterinary Medicine, Norwegian School of Veterinary Science, Tromsø, Norway. morten.tryland@veths.no
Source
Vet Clin Pathol. 2006 Dec;35(4):405-12
Date
Dec-2006
Language
English
Publication Type
Article
Keywords
Aging
Animals
Animals, Wild - blood
Female
Male
Phoca - blood
Reference Values
Svalbard
Abstract
BACKGROUND: Diseases and abnormal physiologic conditions can alter the concentrations of enzymes, metabolites, minerals, and hormones in the blood of animals. The ringed seal (Pusa hispida) has been selected as a key species for environmental monitoring, but information on disease and health parameters for this species is scarce. OBJECTIVES: The aim of the study reported here was to obtain serum chemistry reference intervals for free-ranging ringed seals in Svalbard, and then to evaluate serum chemistry values in relation to age, body condition, and sex. METHODS: Blood samples were collected after death from ringed seals in Wijdefjorden and Billefjorden, Svalbard (2002-2003; n = 75). Serum was analyzed for 24 selected serum chemistry parameters (enzymes, protein, metabolites, minerals, and cortisol). RESULTS: Compared with younger or older animals, seals between 7 and 16 years of age had larger variations in the activities of alanine transaminase, aspartate transaminase, lactate dehydrogenase, and creatine kinase (CK). Animals classified as having low body condition status had more variation in the serum activity of these enzymes, compared with that in animals with higher condition scores. Serum cortisol concentration was higher in young animals (1-5 years) than in older animals. Serum CK activity was higher in males than in females. CONCLUSION: The data reported here may be useful in monitoring the health of ringed seals and for tracking the impact of environmental changes in the Arctic.
PubMed ID
17123246 View in PubMed
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Serum haptoglobin concentrations in ringed seals (Pusa hispida) from Svalbard, Norway.

https://arctichealth.org/en/permalink/ahliterature81299
Source
J Wildl Dis. 2006 Apr;42(2):442-6
Publication Type
Article
Date
Apr-2006
Author
Krafft Bjørn A
Lydersen Christian
Kovacs Kit M
Author Affiliation
Norwegian Polar Institute, N-9296 Tromsø, Norway.
Source
J Wildl Dis. 2006 Apr;42(2):442-6
Date
Apr-2006
Language
English
Publication Type
Article
Keywords
Age Factors
Animals
Female
Haptoglobins - analysis
Male
Norway
Reference Values
Seals, Earless - blood
Sex Factors
Abstract
Haptoglobin (Hp) levels were measured in blood serum from 185 apparently healthy ringed seals (Pusa hispida) from Svalbard (age range, 1-30 yr) collected during the spring seasons of 2002 through 2004. The Hp concentration was 0.26 +/- 0.02 g/l (mean +/- SE; range, 0.0-1.5 g/l). Maturity status, body condition index (CI), interactions between CI and maturity status, and sex and maturity status all had significant influences on Hp levels. Mature males had significantly higher Hp concentrations compared with mature females (0.30 +/- 0.03 vs. 0.17 +/- 0.01 g/l, F(1,16) = 14.9, P
PubMed ID
16870873 View in PubMed
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7 records – page 1 of 1.