| 1. |
- Sinding, Mikkel-Holger S., et al.
(författare)
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Arctic-adapted dogs emerged at the Pleistocene-Holocene transition
- 2020
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 368:6498
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Tidskriftsartikel (refereegranskat)abstract
- Although sled dogs are one of the most specialized groups of dogs, their origin and evolution has received much less attention than many other dog groups. We applied a genomic approach to investigate their spatiotemporal emergence by sequencing the genomes of 10 modern Greenland sled dogs, an similar to 9500-year-old Siberian dog associated with archaeological evidence for sled technology, and an similar to 33,000-year-old Siberian wolf. We found noteworthy genetic similarity between the ancient dog and modern sled dogs. We detected gene flow from Pleistocene Siberian wolves, but not modern American wolves, to present-day sled dogs. The results indicate that the major ancestry of modern sled dogs traces back to Siberia, where sled dog-specific haplotypes of genes that potentially relate to Arctic adaptation were established by 9500 years ago.
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| 2. |
- Ameen, Carly, et al.
(författare)
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Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic
- 2019
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 286:1916
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Tidskriftsartikel (refereegranskat)abstract
- Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but whether the Inuit adopted local Palaeo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Palaeo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Palaeo-Inuit dogs, and probably aided the Inuit expansion across the North American Arctic beginning around 1000 BP.
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| 3. |
- de Wit, Cynthia A., et al.
(författare)
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Organohalogen compounds of emerging concern in Baltic Sea biota : Levels, biomagnification potential and comparisons with legacy contaminants
- 2020
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 144
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Tidskriftsartikel (refereegranskat)abstract
- While new chemicals have replaced major toxic legacy contaminants such as polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT), knowledge of their current levels and biomagnification potential in Baltic Sea biota is lacking. Therefore, a suite of chemicals of emerging concern, including organophosphate esters (OPEs), short-chain, medium-chain and long-chain chlorinated paraffins (SCCPs, MCCPs, LCCPs), halogenated flame retardants (HFRs), and per- and polyfluoroalkyl substances (PFAS), were analysed in blue mussel (Mytilus edulis), viviparous eelpout (Zoarces viviparus), Atlantic herring (Clupea harengus), grey seal (Halichoerus grypus), harbor seal (Phoca vitulina), harbor porpoise (Phocoena phocoena), common eider (Somateria mollissima), common guillemot (Uria aalge) and white-tailed eagle (Haliaeetus albicilla) from the Baltic Proper, sampled between 2006 and 2016. Results were benchmarked with existing data for legacy contaminants. The mean concentrations for Sigma OPEs ranged from 57 to 550 ng g(-1) lipid weight (lw), for Sigma CPs from 110 to 640 ng g(-1) lw for Sigma HFRs from 0.42 to 80 ng g(-1) lw, and for Sigma PFAS from 1.1 to 450 ng g(-1) wet weight. Perfluoro-4-ethyl-cyclohexanesulfonate (PFECHS) was detected in most species. Levels of OPEs, CPs and HFRs were generally similar or higher than those of polybrominated diphenyl ethers (PBDEs) and/or hexabromocyclododecane (HBCDD). OPE, CP and HFR concentrations were also similar to PCBs and DDTs in blue mussel, viviparous eelpout and Atlantic herring. In marine mammals and birds, PCB and DDT concentrations remained orders of magnitude higher than those of OPEs, CPs, HFRs and PFAS. Predator-prey ratios for individual OPEs (0.28-3.9) and CPs (0.40-5.0) were similar or somewhat lower than those seen for BDE-47 (5.0-29) and HBCDD (2.4-13). Ratios for individual HFRs (0.010-37) and PFAS (0.15-47) were, however, of the same order of magnitude as seen for p,p'-DDE (4.7-66) and CB-153 (31-190), indicating biomagnification potential for many of the emerging contaminants. Lack of toxicity data, including for complex mixtures, makes it difficult to assess the risks emerging contaminants pose. Their occurence and biomagnification potential should trigger risk management measures, particularly for MCCPs, HFRs and PFAS.
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| 4. |
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| 5. |
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| 6. |
- Gebbink, Wouter A., et al.
(författare)
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Observation of emerging per- and polyfluoroalkyl substances (PFASs) in Greenland marine mammals
- 2016
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 144, s. 2384-2391
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Tidskriftsartikel (refereegranskat)abstract
- The present pilot study examined emerging per- and polyfluoroalkyl substances (PFASs), i.e., a suite of short chain perfluoroalkyl acids (PFAAs), PFAA precursors and replacement chemicals, and legacy PFASs (long chain length PFAAs) in livers from ringed seals, polar bears and, for the first time, killer whales from East Greenland collected in 2012-2013. Among the emerging PFASs, perfluorobutanesulfonic acid (PFBS) and F-53B (a chlorinated polyfluorinated ether sulfonic acid) were detected in Arctic wildlife, albeit at concentrations approximately four orders of magnitude lower compared to perfluorooctanesulfonic acid (PFOS). PFOS was positively correlated with F-53B, but not PFBS in all three species. A total of 17 PFASs were detected in killer whales, including in a mother-fetus pair, demonstrating maternal transfer. Sigma PFAS concentrations in killer whales (269 +/- 90 ng/g) were comparable to concentrations found in ringed seals (138 +/- 7 ng/g), however, an order of magnitude lower compared to concentrations found in polar bear livers (2336 +/- 263 ng/g). Patterns of long chain PFAAs in killer whales differed from the pattern in ringed seals and polar bears. Of the monitored PFAA precursors, only perfluorooctanesulfonamide (FOSA) was detected in all three species, and FOSA/PFOS ratios and isomer patterns indicated that killer whales have a potential lower metabolic capacity to degrade FOSA compared to polar bears and ringed seals.
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| 7. |
- Liu, Shiping, et al.
(författare)
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Population Genomics Reveal Recent Speciation and Rapid Evolutionary Adaptation in Polar Bears
- 2014
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Ingår i: Cell. - : Elsevier BV. - 0092-8674 .- 1097-4172. ; 157:4, s. 785-794
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Tidskriftsartikel (refereegranskat)abstract
- Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyper-lipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479-343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under strong positive selection are associated with cardiomyopathy and vascular disease, implying important reorganization of the cardiovascular system. One of the genes showing the strongest evidence of selection, APOB, encodes the primary lipoprotein component of low-density lipoprotein (LDL); functional mutations in APOB may explain how polar bears are able to cope with life-long elevated LDL levels that are associated with high risk of heart disease in humans.
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| 8. |
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| 9. |
- Mavaddat, Nasim, et al.
(författare)
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Prediction of Breast Cancer Risk Based on Profiling With Common Genetic Variants
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 1460-2105 .- 0027-8874. ; 107:5, s. 036-036
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Tidskriftsartikel (refereegranskat)abstract
- Background: Data for multiple common susceptibility alleles for breast cancer may be combined to identify women at different levels of breast cancer risk. Such stratification could guide preventive and screening strategies. However, empirical evidence for genetic risk stratification is lacking. Methods: We investigated the value of using 77 breast cancer-associated single nucleotide polymorphisms (SNPs) for risk stratification, in a study of 33 673 breast cancer cases and 33 381 control women of European origin. We tested all possible pair-wise multiplicative interactions and constructed a 77-SNP polygenic risk score (PRS) for breast cancer overall and by estrogen receptor (ER) status. Absolute risks of breast cancer by PRS were derived from relative risk estimates and UK incidence and mortality rates. Results: There was no strong evidence for departure from a multiplicative model for any SNP pair. Women in the highest 1% of the PRS had a three-fold increased risk of developing breast cancer compared with women in the middle quintile (odds ratio [OR] = 3.36, 95% confidence interval [CI] = 2.95 to 3.83). The ORs for ER-positive and ER-negative disease were 3.73 (95% CI = 3.24 to 4.30) and 2.80 (95% CI = 2.26 to 3.46), respectively. Lifetime risk of breast cancer for women in the lowest and highest quintiles of the PRS were 5.2% and 16.6% for a woman without family history, and 8.6% and 24.4% for a woman with a first-degree family history of breast cancer. Conclusions: The PRS stratifies breast cancer risk in women both with and without a family history of breast cancer. The observed level of risk discrimination could inform targeted screening and prevention strategies. Further discrimination may be achievable through combining the PRS with lifestyle/environmental factors, although these were not considered in this report.
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| 10. |
- Mittelholzer, Christian, et al.
(författare)
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Molecular characterization of a novel astrovirus associated with disease in mink
- 2003
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Ingår i: Journal of General Virology. - : Microbiology Society. - 0022-1317 .- 1465-2099. ; 84:11, s. 3087-3094
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Tidskriftsartikel (refereegranskat)abstract
- Pre-weaning diarrhoea is a well-known problem in mink farming in Europe, causing morbidity that varies between farms, regions and season. Different causalities for the disease have been proposed, but only most recently has a novel astrovirus been identified as an important risk factor. In this report, the molecular characterization, origin and evolution of this novel astrovirus of mink are discussed. The polyadenylated, positive-stranded RNA genome was sequenced and found to contain 6610 nt, organized into three ORFs and two short UTRs. A ribosomal frameshift sequence links the 5' two ORFs, containing sequence motifs for a serine protease (ORF1a) and an RNA-dependent RNA polymerase (ORF1b). The structural proteins are encoded by ORF2 and, presumably, are expressed as a polyprotein precursor to be cleaved into the mature capsid proteins. These results indicate that mink astrovirus (MiAstV) has all of the features typical of members of the Astroviridae. Phylogenetic analyses revealed that MiAstV is distantly related to established astroviruses, showing less than 67 % similarity at the nucleotide level with its closest relative, ovine astrovirus, and even lower identities at the predicted amino acid level. Nevertheless, sequence analysis of MiAstV isolates from geographically distinct Swedish and Danish farms showed much less diversity. This suggests either the spread in the mink population of a virus that has evolved a long time ago or the recent introduction of an ancient virus into a new host species.
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| 11. |
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| 12. |
- Olsen, Morten Tange, et al.
(författare)
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A simple route to single-nucleotide polymorphisms in a nonmodel species : identification and characterization of SNPs in the Artic ringed seal (Pusa hispida hispida)
- 2011
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Ingår i: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 11, s. 9-19
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Tidskriftsartikel (refereegranskat)abstract
- Although single-nucleotide polymorphisms (SNPs) have become the marker of choice in the field of human genetics, these markers are only slowly emerging in ecological, evolutionary and conservation genetic analyses of nonmodel species. This is partly because of difficulties associated with the discovery and characterization of SNP markers. Herein, we adopted a simple straightforward approach to identifying SNPs, based on screening of a random genomic library. In total, we identified 768 SNPs in the ringed seal, Pusa hispida hispida, in samples from Greenland and Svalbard. Using three seal samples, SNPs were discovered at a rate of one SNP per 402 bp, whereas re-sequencing of 96 seals increased the density to one SNP per 29 bp. Although applicable to any species of interest, the approach is especially well suited for SNP discovery in nonmodel organisms and is easily implemented in any standard genetics laboratory, circumventing the need for prior genomic data and use of next-generation sequencing facilities.
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| 13. |
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| 14. |
- Pertold, Cino, et al.
(författare)
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Prevalence of skull pathologies in European harbor seals (Phoca vitulina) during 1981–2014
- 2018
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Ingår i: Mammal Research. - : Springer Science and Business Media LLC. - 2199-2401 .- 2199-241X. ; 63:1, s. 55-63
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Tidskriftsartikel (refereegranskat)abstract
- Harbor seals (Phoca vitulina) inhabit the seas surrounding Denmark and are an important top predator in the marine food chain. This trophic position exposes them to environmental contaminants with disease epi- demics and hunting being additional threats to this popu- lation. It is therefore important to study how environmen- tal pollution at the current order of magnitude affects the health of the population. Earlier studies have shown that occurrence of periodontitis could be linked to the amount of pollution the seals were subjected to. In order to inves- tigate this further, 380 skulls and 141 mandibles of harbor seals (Phoca vitulina) from the Wadden Sea, the Limfjord, and Kattegat collected during the period 1970–2014 were examined. The skulls were examined for pathological le- sions. The Hounsfield Units (HU) which are correlated to the bone mineral density (BMD) were measured in a sub- sample (n= 34) using CT scans. The macroscopic examination revealed (with the exception of the Swedish part of Kattegat) a significant increase of pathological lesions over the study period of 1981–2014. The exami- nation of HU showed that median HU measured at mul- tiple sites was highest in the healthy skulls compared to the skulls with one or more of the lesions. A discriminant analysis allowed high discriminatory capacity to separate healthy skulls from the skulls with pathologies, simply by the utilization of the HU data. Former studies of BMD in marine mammals have shown that exposure to environ- mental chemicals alter BMD and cause periodontitis. The present study, based on temporal and spatial trends in BMD, confirms the results of previous studies Prevalence of skull pathologies in European harbor seals (Phoca vitulina) during 1981–2014 (PDF Download Available). Available from: https://www.researchgate.net/publication/320586176_Prevalence_of_skull_pathologies_in_European_harbor_seals_Phoca_vitulina_during_1981-2014 [accessed Dec 15 2017].
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| 15. |
- Schmidt, Britta, et al.
(författare)
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Liver histopathology of Baltic grey seals (Halichoerus grypus) over three decades
- 2020
-
Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750.
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Tidskriftsartikel (refereegranskat)abstract
- The liver plays an important role in the metabolism and elimination of endogenic and exogenic lipid-solublecompounds. Multiple studies have shown that polychlorinated biphenyls (PCB) and dichlorodiphenyl trichloroethane(DDT) lead to morphological changes in liver cells. The aim of the present study was therefore toanalyse liver changes over time in Baltic grey seals (Halichoerus grypus) and to correlate these with historical PCBand DDT contaminations. A total of 191 liver samples were collected between 1981 and 2015 in the Gulf ofBothnia and northern Baltic Proper. Six histological features were evaluated, including portal mononuclear cellinfiltration, random mononuclear cell infiltration, lipid granulomas, hepatocellular fat vacuoles, hepatic stellatecells and mild multifocal bile duct hyperplasia accompanied by portal fibrosis. Three of the six lesions showed asignificant correlation with age. Furthermore, a positive correlation between portal mononuclear cell infiltrationand mild multifocal bile duct hyperplasia was found. Additionally, lipid granulomas were significantly correlatedwith hepatic stellate cells. More importantly, hepatic stellate cells and mild multifocal bile duct hyperplasia werecorrelated with adipose tissue (blubber) concentrations of ƩPCB, measured in a subsample (n = 34) of all individuals.No correlation with lesions and ƩDDT concentrations were found. These results show that age is animportant factor for the development of these liver lesions, but PCBs burden may be an influencing factor. This isin agreement with previous studies of marine mammals in the Baltic Sea as well as in the Arctic. We thereforeconclude that not only age of the animals, but also exposure to PCBs should be taken into account when understandingand evaluating the current health status of Baltic grey seals.
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| 16. |
- Schmidt, Britta, et al.
(författare)
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Variation in skull bone mineral density of ringed seals (Phoca hispida) from the Gulf of Bothnia and West Greenland between 1829 and 2019
- 2020
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750.
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Tidskriftsartikel (refereegranskat)abstract
- Bone is remodelled constantly through a balance of bone formation and resorption. This process can be affectedby various factors such as hormones, vitamins, nutrients and environmental factors, which can create an imbalanceresulting in systemic or local bone alteration. The aim of the present study was to analyse the changes in bone mineral density (BMD) over time in skulls of ringed seals (Pusa hispida) from the Baltic and Greenland using museum samples. Overall, 303 skulls (102 Male, 89 Female, 112 unknown) were used for bone investigationsand were divided into three periods according to collection year: before 1958 (n = 167), between 1958 and 1989 (n=40) and after 1994 up to 2019 (n=96). All skulls were examined by dual-energy X-ray absorptiometryto obtain the BMD. Skull BMD of the Baltic seals was positively correlated with the historical polychlorinatedbiphenyls (PCB) contamination having potential effects on the constitution of bones. BMD fluctuated between the three study periods (LM: p-value < 0.001, F-value = 47.5) with the lowest BMD found between 1897 and 1957, in the Gulf of Bothnia, where the highest peak of contaminant concentration was in the second period. BMD levels increased with increasing PCB concentration (LM: p < 0.001). The Greenland population showed significant lower BMD levels in the pollution and post-pollution period than the Baltic population (LM:p < 0.001). It also revealed a higher BMD in males than in females (LM: p=0.03). In conclusion, the variations between 1829 and 2019 in the Baltic Sea and Greenland may to a certain extent reflect normal fluctuations; however, this study revealed several factors affecting BMD, including sex and PCB levels.
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| 17. |
- Silva, William, et al.
(författare)
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Life cycle bioenergetics of the gray seal (Halichoerus grypus) in the Baltic Sea: Population response to environmental stress
- 2020
-
Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 145
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Tidskriftsartikel (refereegranskat)abstract
- Wildlife population dynamics are shaped by multiple natural and anthropogenic factors, including predation, competition, stressful life history events, and external environmental stressors such as diseases and pollution. Marine mammals such as gray seals rely on extensive blubber layers for insulation and energy storage, making this tissue critical for survival and reproduction. This lipid rich blubber layer also accumulates hazardous fat soluble pollutants, such as polychlorinated biphenyls (PCBs), that can directly impact adipose function or be mobilized during periods of negative energy balance or transferred to offspring to exert further impacts on target tissues or vulnerable life stages. To predict how marine mammals will respond to ecological and anthropogenic stressors, it is necessary to use process-based modelling approaches that integrate environmental inputs, full species life history, and stressor impacts with individual dynamics of energy intake, storage, and utilization. The purpose of this study was to develop a full lifecycle dynamic energy budget and individual based model (DEB-IBM) that captured Baltic gray seal physiology and life history, and showcase potential applications of the model to predict population responses to select stressors known to threaten gray seals and other marine mammals around the world. We explore variations of three ecologically important stressors using phenomenological simulations: food limitation, endocrine disrupting chemicals that reduce fertility, and infectious disease. Using our calibrated DEB-IBM for Baltic gray seals, we found that continuous incremental food limitation can be more detrimental to population size than short random events of starvation, and further, that the effect of endocrine disruptors on population growth and structure is delayed due to bioaccumulation, and that communicable diseases significantly decrease population growth even when spillover events are relatively less frequent. One important finding is the delayed effect on population growth rate from some stressors, several years after the exposure period, resulting from a decline in somatic growth, increased age at maturation and decreased fecundity. Such delayed responses are ignored in current models of population viability and can be important in the correct assessment of population extinction risks. The model presented here provides a test bed on which effects of new hazardous substances and different scenarios of future environmental change affecting food availability and/or seal energetic demands can be investigated. Thus, the framework provides a tool for better understanding how diverse environmental stressors affect marine mammal populations and can be used to guide scientifically based management.
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| 18. |
- Sinding, Mikkel-Holger S., et al.
(författare)
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Population genomics of grey wolves and wolf-like canids in North America
- 2018
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 14:11
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Tidskriftsartikel (refereegranskat)abstract
- North America is currently home to a number of grey wolf (Canis lupus) and wolf-like canid populations, including the coyote (Canis latrans) and the taxonomically controversial red, Eastern timber and Great Lakes wolves. We explored their population structure and regional gene flow using a dataset of 40 full genome sequences that represent the extant diversity of North American wolves and wolf-like canid populations. This included 15 new genomes (13 North American grey wolves, 1 red wolf and 1 Eastern timber/Great Lakes wolf), ranging from 0.4 to 15x coverage. In addition to providing full genome support for the previously proposed coyote-wolf admixture origin for the taxonomically controversial red, Eastern timber and Great Lakes wolves, the discriminatory power offered by our dataset suggests all North American grey wolves, including the Mexican form, are monophyletic, and thus share a common ancestor to the exclusion of all other wolves. Furthermore, we identify three distinct populations in the high arctic, one being a previously unidentified "Polar wolf" population endemic to Ellesmere Island and Greenland. Genetic diversity analyses reveal particularly high inbreeding and low heterozygosity in these Polar wolves, consistent with long-term isolation from the other North American wolves.
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| 19. |
- Sonne, Christian, et al.
(författare)
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A review of pathogens in selected Baltic Sea indicator species
- 2020
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750.
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Forskningsöversikt (refereegranskat)abstract
- Here we review the state-of-the-art of pathogens in select marine and terrestrial key species of the Baltic Sea, i.e.ringed seal (Pusa hispida), harbour seal (Phoca vitulina), grey seal (Halichoerus grypus), harbour porpoise(Phocoena phocoena), common eider (Somateria mollissima), pink-footed goose (Anser brachyrhynchus) and whitetailedeagle (Haliaeetus albicilla). This review is the first to merge and present available information and baselinedata for the FP7 BONUS BaltHealth project: Baltic Sea multilevel health impacts on key species of anthropogenichazardous substances. Understanding the spread, prevalence and effects of wildlife pathogens is important for theunderstanding of animal and ecosystem health, ecosystem function and services, as well as human exposure tozoonotic diseases. This review summarises the occurrence of parasites, viruses and bacteria over the past sixdecades, including severe outbreaks of Phocine Distemper Virus (PDV), the seroprevalence of Influenza A andthe recent increase in seal parasites. We show that Baltic high trophic key species are exposed to multiplebacterial, viral and parasitic diseases. Parasites, such as C. semerme and P. truncatum present in the colon andliver Baltic grey seals, respectively, and anisakid nematodes require particular monitoring due to their effects onanimal health. In addition, distribution of existing viral and bacterial pathogens, along with the emergence andspread of new pathogens, need to be monitored in order to assess the health status of key Baltic species. Relevantbacteria are Streptococcus spp., Brucella spp., Erysipelothrix rhusiopathiae, Mycoplasma spp. and Leptospira interrogans;relevant viruses are influenza virus, distemper virus, pox virus and herpes virus. This is of special importanceas some of the occurring pathogens are zoonotic and thus also pose a potential risk for human health.Marine mammal handlers, as well as civilians that by chance encounter marine mammals, need to be aware ofthis risk. It is therefore important to continue the monitoring of diseases affecting key Baltic species in order toassess their relationship to population dynamics and their potential threat to humans. These infectious agents arevaluable indicators of host ecology and can act as bioindicators of distribution, migration, diet and behaviour ofmarine mammals and birds, as well as of climate change and changes in food web dynamics. In addition, infectiousdiseases are linked to pollutant exposure, overexploitation, immune suppression and subsequent inflammatorydisease. Ultimately, these diseases affect the health of the entire ecosystem and, consequently,ecosystem function and services. As global warming is continuously increasing, the impact of global change oninfectious disease patterns is important to monitor in Baltic key species in the future.
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| 20. |
- Spaan, Kyra M., et al.
(författare)
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Fluorine Mass Balance and Suspect Screening in Marine Mammals from the Northern Hemisphere
- 2020
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 54:7, s. 4046-4058
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Tidskriftsartikel (refereegranskat)abstract
- There is increasing evidence that the similar to 20 routinely monitored perfluoroalkyl and polyfluoroalkyl substances (PFASs) account for only a fraction of extractable organofluorine (EOF) occurring in the environment. To assess whether PFAS exposure is being underestimated in marine mammals from the Northern Hemisphere, we performed a fluorine mass balance on liver tissues from 11 different species using a combination of targeted PFAS analysis, EOF and total fluorine determination, and suspect screening. Samples were obtained from the east coast United States (US), west and east coast of Greenland, Iceland, and Sweden from 2000 to 2017. Of the 36 target PFASs, perfluorooctane sulfonate (PFOS) dominated in all but one Icelandic and three US samples, where the 7:3 fluorotelomer carboxylic acid (7:3 FTCA) was prevalent. This is the first report of 7:3 FTCA in polar bears (similar to 1000 ng/g, ww) and cetaceans (<6-190 ng/g, ww). In 18 out of 25 samples, EOF was not significantly greater than fluorine concentrations derived from sum target PFASs. For the remaining 7 samples (mostly from the US east coast), 30-75% of the EOF was unidentified. Suspect screening revealed an additional 37 PFASs (not included in the targeted analysis) bringing the total to 63 detected PFASs from 12 different classes. Overall, these results highlight the importance of a multiplatform approach for accurately characterizing PFAS exposure in marine mammals.
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| 21. |
- Styrishave, Bjarne, et al.
(författare)
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Steroid hormones in multiple tissues of East Greenland polar bears (Ursus maritimus)
- 2017
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Ingår i: Polar Biology. - 0722-4060 .- 1432-2056. ; 40:1, s. 37-49
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Tidskriftsartikel (refereegranskat)abstract
- The polar bear (Ursus maritimus) is threatened by climate changes and also from persistent organic pollutants affecting polar bear endocrinology governing growth and reproduction. To provide further insight into basic polar bear endocrinology, we determined the levels of steroids in multiple tissues and plasma from East Greenland polar bears. Tissue samples from 10 polar bears, 5 males (2 adults, 3 juveniles) and 5 females (all juveniles) were obtained from the Inuit hunt in Scoresby Sound during springtime. Eleven steroids: pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, dihydrotestosterone, estrone, 17 alpha-estradiol and 17 beta-estradiol were determined in brain, adrenal cortex, testis, testicular vein, plasma, and ovary using GC-MS/MS. In brain tissue, the neuroactive progestagen pregnenolone (11.9 +/- 4.4 ng/g ww) and dehydroepiandrosterone (2.26 +/- 0.43 ng/g ww) were found in high concentrations. Very high levels of testosterone and androstenedione were observed in testes (> 100 ng/g ww) and plasma from testicular vein (testosterone: 108 +/- 41 ng/ml; androstenedione: 35.2 +/- 11.1 ng/ml). Additionally, a strong correlation was found between the levels of steroids in testes and testicular vein plasma. Progestagens were found in very high levels in ovaries from juvenile females (> 100 ng/g ww). Finally, our study indicates that polar bears synthesize androstenedione via the a dagger-4 pathway. The present study adds new insight to our knowledge on polar bear endocrinology, which may be used in future studies on polar bear ecology and studies on some of the threats from pollution and climate changes that these animals are facing.
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| 22. |
- Styrishave, Bjarne, et al.
(författare)
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Steroid hormones in multiple tissues of East Greenland polar bears (Ursus maritimus)
- 2017
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Ingår i: Polar Biology. - : Springer Verlag. - 0722-4060 .- 1432-2056. ; 40:1, s. 37-49
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Tidskriftsartikel (refereegranskat)abstract
- The polar bear (Ursus maritimus) is threatened by climate changes and also from persistent organic pollutants affecting polar bear endocrinology governing growth and reproduction. To provide further insight into basic polar bear endocrinology, we determined the levels of steroids in multiple tissues and plasma from East Greenland polar bears. Tissue samples from 10 polar bears, 5 males (2 adults, 3 juveniles) and 5 females (all juveniles) were obtained from the Inuit hunt in Scoresby Sound during springtime. Eleven steroids: pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, dihydrotestosterone, estrone, 17 alpha-estradiol and 17 beta-estradiol were determined in brain, adrenal cortex, testis, testicular vein, plasma, and ovary using GC-MS/MS. In brain tissue, the neuroactive progestagen pregnenolone (11.9 +/- 4.4 ng/g ww) and dehydroepiandrosterone (2.26 +/- 0.43 ng/g ww) were found in high concentrations. Very high levels of testosterone and androstenedione were observed in testes (> 100 ng/g ww) and plasma from testicular vein (testosterone: 108 +/- 41 ng/ml; androstenedione: 35.2 +/- 11.1 ng/ml). Additionally, a strong correlation was found between the levels of steroids in testes and testicular vein plasma. Progestagens were found in very high levels in ovaries from juvenile females (> 100 ng/g ww). Finally, our study indicates that polar bears synthesize androstenedione via the a dagger-4 pathway. The present study adds new insight to our knowledge on polar bear endocrinology, which may be used in future studies on polar bear ecology and studies on some of the threats from pollution and climate changes that these animals are facing.
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| 23. |
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| 24. |
- van Beest, Floris M, et al.
(författare)
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Classifying grey seal behaviour in relation to environmental variability and commercial fishing activity -a multivariate hidden Markov model
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Classifying movement behaviour of marine predators in relation to anthropogenic activity and environmental conditions is important to guide marine conservation. We studied the relationship between grey seal (Halichoerus grypus) behaviour and environmental variability in the southwestern Baltic Sea where seal-fishery conflicts are increasing. We used multiple environmental covariates and proximity to active fishing nets within a multivariate hidden Markov model (HMM) to quantify changes in movement behaviour of grey seals while at sea. Dive depth, dive duration, surface duration, horizontal displacement, and turning angle were used to identify travelling, resting and foraging states. The likelihood of seals foraging increased in deeper, colder, more saline waters, which are sites with increased primary productivity and possibly prey densities. Proximity to active fishing net also had a pronounced effect on state occupancy. The probability of seals foraging was highest <5 km from active fishing nets (51%) and decreased as distance to nets increased. However, seals used sites <5 km from active fishing nets only 3% of their time at sea highlighting an important temporal dimension in seal-fishery interactions. By coupling high-resolution oceanographic, fisheries, and grey seal movement data, our study provides a scientific basis for designing management strategies that satisfy ecological and socioeconomic demands on marine ecosystems.
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| 25. |
- Weisser, Johan J., et al.
(författare)
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A novel method for analysing key corticosteroids in polar bear (Ursus maritimus) hair using liquid chromatography tandem mass spectrometry
- 2016
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Ingår i: Journal of chromatography. B. - 1570-0232 .- 1873-376X. ; 1017, s. 45-51
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the development and evaluation of a methodology for extraction, clean-up and analysis of three key corticosteroids (aldosterone, cortisol and corticosterone) in polar bear hair. Such a methodology can be used to monitor stress biomarkers in polar bears and may provide as a useful tool for long-term and retrospective information. We developed a combined pressurized liquid extraction (PLE)-solid phase extraction (SPE) procedure for corticosteroid extraction and clean-up followed by high pressure liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analysis. This procedure allows for the simultaneous determination of multiple steroids, which is in contrast to previous polar bear studies based on ELISA techniques. Absolute method recoveries were 81%, 75% and 60% for cortisol, corticosterone and aldosterone, respectively. We applied the developed method on a hair sample pooled from four East Greenland polar bears. Herein cortisol and corticosterone were successfully determined in levels of 0.32 +/- 0.02 ng/g hair and 0.13 +/- 0.02 ng/g hair, respectively. Aldosterone was below limit of detection (LOD<0.17 ng/g). The cortisol hair concentration found in these East Greenland polar bears was consistent with cortisol levels previously determined in the Southern Hudson Bay and James Bay in Canada using ELISA kits. (C) 2016 Elsevier B.V. All rights reserved.
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