| trace element levels in harp seal (pagophilus groenlandicus) and hooded seal (cystophora cristata) from the greenland sea. a multivariate approach. | concentrations of the essential trace elements, iron, copper, zinc and selenium and the non-essential elements arsenic, cadmium, total mercury and lead, were measured in the meat, liver and kidney of two species of seals, harp seal (pagophilus groenlandicus) and hooded seal (cystophora cristata) collected in the greenland sea. the spread among the individual seals was considerable. however, multivariate statistics simplified the evaluation of the data. the muscle tissue contained lower levels of ... | 2000 | 10811256 |
| fat transfer and energetics during lactation in the hooded seal: the roles of tissue lipoprotein lipase in milk fat secretion and pup blubber deposition. | hooded seals (cystophora cristata) lactate for 3.6 days during which females simultaneously fast and transfer large amounts of energy to their pups through fat-rich milk. pups grow rapidly, principally due to blubber deposition. lipoprotein lipase (lpl), the primary enzyme responsible for tissue uptake of triglyceride fatty acids, may strongly influence both maternal milk fat secretion and pup blubber deposition. we measured the energetic costs of lactation (using hydrogen isotope dilution, 3h2o ... | 1999 | 10549140 |
| effects of adrenergic and cholinergic drugs on splenic arteries and veins from hooded seals (cystophora cristata). | isolated ring preparations of arteries and veins from hooded seal spleens were subjected in vitro to adrenaline (a), noradrenaline (na), isoprenaline (iso), and acetylcholine (ach), alone or in combination with the blockers phentolamine (phe), propranolol (pro), and atropine (atr). both arteries and veins constricted in response to a (the estimated effective dose required for half-maximal response (ed50) was 3.3 and 0.2 microm, for arteries and veins, respectively) and na (estimated ed50 was 1.5 ... | 1998 | 9773508 |
| volume capacity and contraction control of the seal spleen. | volume changes in the spleens of hooded seals (cystophora cristata) and harp seals (phoca groenlandica) were measured plethysmographically in vitro in response to epinephrine, norepinephrine, isoprenaline, phentolamine, and acetylcholine. dilated spleens contracted forcefully within 1-3 min of alpha-adrenoceptor activation with 1.0-5.0 micrograms epinephrine/kg body mass, whereas stimulation of beta-adrenoceptors and cholinergic receptors had little effect. the mass of dilated hooded seal spleen ... | 1997 | 9173968 |
| energetics during nursing and early postweaning fasting in hooded seal (cystophora cristata) pups from the gulf of st lawrence, canada. | in this study we measured growth and milk intake and calculated energy intake and its allocation into metabolism and stored tissue for hooded seal (cystophora cristata) pups. in addition, we measured mass loss, change in body composition and metabolic rate during the first days of the postweaning fast. the mean body mass of the hooded seal pups (n = 5) at the start of the experiments, when they were new-born, was 24.3 +/- 1.3 kg (sd). they gained an average of 5.9 +/- 1.1. kg.day-1 of which 19% ... | 1997 | 9120069 |
| prenatal and postnatal transfer of fatty acids from mother to pup in the hooded seal. | unlike most mammals, hooded seal (cystophora cristata) pups are born with a substantial layer of adipose tissue. subsequently, during the brief lactation period of only 4 days, fasting mothers mobilize enormous amounts of lipid from blubber and secrete milk (60% fat) at rates of 10 kg.day-1. pups gain 7 kg.day-1 due primarily to the deposition of fat in blubber. we measured blubber content and fatty acid composition of blubber and milk in hooded seal mother-pup pairs at birth and over the 4-day ... | 1995 | 7601954 |
| paternity exclusion by dna fingerprinting, and mate guarding in the hooded seal cystophora cristata. | hooded seal cystophora cristata trios consist of an adult female, her pup, and an attending adult male. using dna fingerprinting, we excluded the possibility that the attending males within hooded seal trios were the fathers of the pups, proving that these hooded seals did not remain paired from one breeding season to the next. behavioural observations of the trios after capture and release revealed that male hooded seals displace one another in attending nursing females. mate guarding appears t ... | 1994 | 8019687 |
| adrenergic vasomotor responses in nasal mucosa of hooded seals. | in seals respiratory heat and water losses are restricted through nasal heat exchange. the heat exchange efficiency is apparently controlled through adjustments in the nasal mucosal blood flow rate and/or pattern. in this study the adrenergic mechanisms involved in regulation of mucosal blood flow were investigated. the nasal mucosal vasculature of 14 newly killed hooded seal (cystophora cristata) pups was perfused by a constant-flow peristaltic pump with 37 degrees c oxygenated modified krebs s ... | 1992 | 1481941 |
| fatty-acyl esters of retinol (vitamin a) in the liver of the harp seal (phoca groenlandica), hooded seal (cystophora cristata), and california sea lion (zalophus californianus). | the fatty-acid composition of retinyl esters in the livers of two species of phocid seal, the harp seal (phoca groenlandica, n = 20) and the hooded seal (cystophora cristata, n = 15), and one species of otariid seal, the california sea lion (zalophus californianus, n = 6), was determined. vitamin a ranged in concentration from 4 to 1024 nmol retinol/g liver for the phocids and from 381 to 979 nmol/g liver for the otariids. in most of the livers, retinyl palmitate was not the principal ester, and ... | 1992 | 1482558 |
| distributional pattern of zinc, cadmium, mercury, and selenium in livers of hooded seal (cystophora cristata). | the liver of hooded seal (cystophora cristata) consists of six lobes of unequal sizes. extensive sampling by means of cutout samples covering the depth horizon 2-30 mm below liver surface indicates that the liver may be considered homogeneous as to concentrations of zinc, cadmium, mercury, and selenium (residuals of overall mean compatible with normality, the all-organ variance negligibly in excess of within-lobe variance). mercury and selenium are present in equimolar concentrations. cutout sam ... | 1990 | 1702660 |
| electrophoretic variation in large mammals. iii. the ringed seal, pusa hispida, the harp seal, pagophilus groenlandicus, and the hooded seal, cystophora cristata. | | 1982 | 7129942 |
| narcotics in hooded seals (cystophora cristata): a preliminary report. | | 1979 | 519554 |
| hypoxia in freely diving hooded seal, cystophora cristata. | | 1976 | 9243 |
| the respiratory properties of the blood of the bladdernose seal (cystophora cristata). | | 1969 | 5809093 |
| [the larynx of the hood seal (cystophora cristata erxleben 1777). a further contribution to the comparative anatomy of the seal larynx]. | | 1963 | 13992179 |
| the 'hood' of the hooded seal, cystophora cristata. | | 1884 | 17751166 |
| radiocaesium (137cs) in marine mammals from svalbard, the barents sea and the north greenland sea. | specific activities of the anthropogenic radionuclide, 137cs, were determined in marine mammals from svalbard and the barents and north greenland seas. muscle samples were collected from 12 polar bears, 15 ringed seals, 10 hooded seals, 7 bearded seals, 14 harp seals, one walrus, one white whale and one blue whale in the period 2000-2003. the mean concentrations (+/-sd) of 137cs were: 0.72+/-0.62 bq/kg wet weight (w.w.) for polar bears; 0.49+/-0.07 bq/kg w.w. for ringed seals; 0.25+/-0.10 bq/kg ... | 2006 | 16154620 |
| brominated flame retardants and organochlorine contaminants in winter flounder, harp and hooded seals, and north atlantic right whales from the northwest atlantic ocean. | various brominated flame retardants (bfrs), including polybrominated diphenyl ethers (pbdes) and current-use, non-pbde bfrs, as well as organochlorine (oc) pesticides and polychlorinated biphenyls (pcbs), were measured in winter flounder, harp and hooded seals, and north atlantic right whales from the eastern united states and canada. the concentrations of pbdes in winter flounder and right whales were similar in magnitude to the levels of pcbs, which was unlike the pattern observed in seals. in ... | 2010 | 20434733 |
| levels of alpha-hch, lindane, and enantiomeric ratios of alpha-hch in marine mammals from the northern hemisphere. | the enantiomeric ratios of alpha-hch were determined by chiral gas chromatography in blubber of marine mammals from regions of the northern hemisphere (north sea, baltic sea, arctic and iceland). cetaceans (harbour porpoises and white-beaked dolphins) showed a preferential accumulation of (+)-alpha-hch. in blubber of harbour seals, grey seals and harp seals (+)-alpha-hch was also more abundant than (-)-alpha-hch. hooded seals formed an exception with a (+/-) enantiomeric ratio of alpha-hch < 1. | 1995 | 8528649 |
| global change effects on the long-term feeding ecology and contaminant exposures of east greenland polar bears. | rapid climate changes are occurring in the arctic, with substantial repercussions for arctic ecosystems. it is challenging to assess ecosystem changes in remote polar environments, but one successful approach has entailed monitoring the diets of upper trophic level consumers. quantitative fatty acid signature analysis (qfasa) and fatty acid carbon isotope (δ(13) c-fa) patterns were used to assess diets of east greenland (eg) polar bears (ursus maritimus) (n = 310) over the past three decades. qf ... | 2013 | 23640921 |
| quantifying the sensitivity of arctic marine mammals to climate-induced habitat change. | we review seven arctic and four subarctic marine mammal species, their habitat requirements, and evidence for biological and demographic responses to climate change. we then describe a pan-arctic quantitative index of species sensitivity to climate change based on population size, geographic range, habitat specificity, diet diversity, migration, site fidelity, sensitivity to changes in sea ice, sensitivity to changes in the trophic web, and maximum population growth potential (r(max)). the index ... | 2008 | 18494365 |
| carbon, nitrogen and sulphur isotopic fractionation in captive juvenile hooded seal (cystophora cristata): application for diet analysis. | intrinsic biogeochemical markers, such as stable isotope ratios of carbon, nitrogen and sulphur are increasingly used to trace the trophic ecology of marine top predators. however, insufficient knowledge of fractionation processes in tissues continues to hamper the use of these markers. | 2017 | 28809062 |
| estimating fiber orientation distribution functions in 3d-polarized light imaging. | research of the human brain connectome requires multiscale approaches derived from independent imaging methods ideally applied to the same object. hence, comprehensible strategies for data integration across modalities and across scales are essential. we have successfully established a concept to bridge the spatial scales from microscopic fiber orientation measurements based on 3d-polarized light imaging (3d-pli) to meso- or macroscopic dimensions. by creating orientation distribution functions ... | 2016 | 27147981 |
| ascending aorta of hooded seals with particular emphasis on its vasa vasorum. | the pressure-volume relationship in the ascending aorta ("windkessel") of the hooded seal was determined and the morphology of its vasa vasorum described in some detail. we found that the ascending aorta has a high compliance and can easily accommodate the entire stroke volume when the peripheral vascular resistance becomes much increased and maintain perfusion pressure during the much extended diastole and thereby reduce cardiac stroke work during diving. we also found that the 3- to 5-mm thick ... | 2016 | 27122367 |
| understanding fiber mixture by simulation in 3d polarized light imaging. | 3d polarized light imaging (3d-pli) is a neuroimaging technique that has opened up new avenues to study the complex architecture of nerve fibers in postmortem brains. the spatial orientations of the fibers are derived from birefringence measurements of unstained histological brain sections that are interpreted by a voxel-based analysis. this, however, implies that a single fiber orientation vector is obtained for each voxel and reflects the net effect of all comprised fibers. the mixture of vari ... | 2015 | 25700950 |
| new data on the cellular composition of the hooded seal blood. | | 2016 | 21221906 |
| slow intrinsic oscillations in thick neocortical slices of hypoxia tolerant deep diving seals. | direct evidence that the mammalian neocortex is an important generator of intrinsic activity comes from isolated neocortical slices that spontaneously generate multiple rhythms including those in the beta, delta and gamma range. these oscillations are also seen in intact animals where they interact with other areas including the hippocampus, thalamus and basal ganglia. here we show that thick isolated neocortical slices from hooded seals intrinsically generate persistent spontaneous activities, ... | 2011 | 21185914 |
| ecological characterisation of the colonic microbiota in arctic and sub-arctic seals. | dominant colonic bacteria in wild hooded (n = 9), harbour (n = 1) and grey (n = 1) seals were identified using 16s rrna gene clone libraries (313 clones), revealing 52.7% bacteroidetes, 41.5% firmicutes, 4.5% proteobacteria and 1.0% fusobacteria. thirty (77%) of the 39 phylotypes identified were novel, showing <97% sequence similarity to their nearest cultivated relatives. mean colonic bacterial cell density, determined by real-time pcr, was high (12.8 log(10) cells/g wet wt) for the hooded seal ... | 2010 | 20523986 |
| development of aerobic and anaerobic metabolism in cardiac and skeletal muscles from harp and hooded seals. | in diving animals, skeletal muscle adaptations to extend underwater time despite selective vasoconstriction include elevated myoglobin (mb) concentrations, high acid buffering ability (beta) and high aerobic and anaerobic enzyme activities. however, because cardiac muscle is perfused during dives, it may rely less heavily on mb, beta and anaerobic pathways to support contractile activity. in addition, because cardiac tissue must sustain contractile activity even before birth, it may be more phys ... | 2010 | 20154189 |
| structural characterization of multibranched oligosaccharides from seal milk by a combination of off-line high-performance liquid chromatography-matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry and sequential exoglycosidase digestion. | a complex mixture of diverse oligosaccharides related to the carbohydrates in glycoconjugates involved in various biological events is found in animal milk/colostrum and has been challenging targets for separation and structural studies. in the current study, we isolated oligosaccharides having high molecular masses (mw approximately 3800) from the milk samples of bearded and hooded seals and analyzed their structures by off-line normal-phase-high-performance liquid chromatography-matrix-assiste ... | 2009 | 19275874 |
| tissue-specific accumulation and lactational transfer of polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants in hooded seals (cistophora cristata) from the gulf of st. lawrence: applications for monitoring. | accumulation and mother-pup transfer of halogenated organic contaminants was studied in hooded seal tissues from eastern canada. blubber polychlorinated biphenyl (pcb) and total pesticide concentrations were relatively high, possibly due to their high trophic level and demersal feeding habits. blood plasma showed the lowest contaminant concentrations compared to blubber and liver, possibly due to a lower affinity of these compounds to lipoproteins in blood plasma. total contaminant body burden c ... | 2006 | 16325312 |
| shrapnell's membrane in a mammal exposed to extreme pressure variations: morphological and radiological observations in the hooded seal. | the function of shrapnell's membrane (pars flaccida; pf) in middle-ear mechanics is still an enigma, though numerous proposals have been put forward, e.g. protection of pars tensa, equalizing of middle-ear pressure, sound transmission, and the site of origin of otitis media. in this study the pf was studied in a mammal (the hooded seal) which exposes itself to extreme pressure differences (from 1 to 100 atmospheres) when diving. formaldehyde-fixed temporal bones obtained from newborn, one-year-o ... | 2003 | 14653915 |
| chemical characterization of the oligosaccharides in milk of high arctic harbour seal (phoca vitulina vitulina). | carbohydrates were extracted from high arctic harbour seal milk, phoca vitulina vitulina (family phocidae). free neutral oligosaccharides were separated by gel filtration and preparative thin layer chromatography, while free sialyl oligosaccharides were separated by gel filtration and then purified by ion exchange chromatography, gel filtration and high performance liquid chromatography. oligosaccharide structures were determined by 1h-nmr spectroscopy. the structures of the neutral oligosacchar ... | 2003 | 12890545 |
| wandering hooded seals. | | 2002 | 11811199 |
| what is your diagnosis? blood from an injured female hooded seal. | | 1997 | 12658579 |
| positional specificity of gastric hydrolysis of long-chain n-3 polyunsaturated fatty acids of seal milk triglycerides. | long-chain n-3 polyunsaturated fatty acids (n-3 pufa) of marine oils are important dietary components for both infants and adults, and are incorporated into milks following maternal dietary intake. however, little is known about the hydrolysis of these pufa from milk triglycerides (tg) by lipases in suckling young. seals, like humans, possess gastric lipase; however, the milk lipids of seals and sea lions are almost devoid of the readily hydrolyzable medium-chain fatty acids, and are characteriz ... | 1992 | 1491605 |
| application of real-time quantitative pcr assays for detecting marine brucella spp. in fish. | brucella ceti and brucella pinnipedialis have been documented as occurring in marine mammals, and b. ceti has been identified in 3 naturally acquired human cases. seroconversion and infection patterns in pacific northwest harbor seals ( phoca vitulina richardii) and north atlantic hooded seals ( cystophora cristata) indicate post-weaning exposure through prey consumption or lungworm infection, suggesting fish and possibly invertebrates play an epizootiologic role in marine brucella transmission ... | 2018 | 28985698 |
| angioarchitecture of collateral arteries of the aortic arch of antillean manatee (trichechus manatus manatus linnaeus, 1758). | the aortic arrangement is an important structure associated with the maintenance of homeostasis. based on this information, this study was conducted to describe the collateral arteries of the aortic arch of antillean manatee and define the standard model for the species. three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of rio grande do norte, brazil, were used. the study was performed in the laboratory of morphophysiology of vertebrates of ... | 2020 | 31441103 |
| seroprevalence for brucella spp. in baltic ringed seals (phoca hispida) and east greenland harp (pagophilus groenlandicus) and hooded (cystophora cristata) seals. | zoonotic infections transmitted from marine mammals to humans in the baltic and european arctic are of unknown significance, despite given considerable potential for transmission due to local hunt. here we present results of an initial screening for brucella spp. in arctic and baltic seal species. baltic ringed seals (pusa hispida, n = 12) sampled in october 2015 and greenland sea harp seals (pagophilus groenlandicus, n = 6) and hooded seals (cystophora cristata, n = 3) sampled in march 2015 wer ... | 2018 | 29571513 |
| links between muscle phenotype and life history: differentiation of myosin heavy chain composition and muscle biochemistry in precocial and altricial pinniped pups. | in marine mammals, muscular development has been identified as a rate-limiting factor in achieving adult dive capacities. this study investigates the rate that myosin heavy chain (mhc) composition matures in a postural and locomotor skeletal muscle for four pinniped species with different lactation lengths: hooded seals, cystophora cristata; harp seals, pagophilus groenlandicus; northern fur seals, callorhinus ursinus, and steller sea lions, eumetopias jubatus. the ontogeny of mhc isoform expres ... | 2019 | 31616978 |
| characterisation of north american brucella isolates from marine mammals. | extension of known ecological niches of brucella has included the description of two novel species from marine mammals. brucella pinnipedialis is associated predominantly with seals, while two major brucella ceti clades, most commonly associated with porpoises or dolphins respectively, have been identified. to date there has been limited characterisation of brucella isolates obtained from marine mammals outside northern european waters, including north american waters. to address this gap, and e ... | 2017 | 28934239 |
| perfluoroalkyl substances (pfass) in white whales (delphinapterus leucas) from svalbard - a comparison of concentrations in plasma sampled 15 years apart. | the objective of the present study was to investigate recent concentrations of perfluoroalkyl substances (pfass) in white whales (delphinapterus leucas) from svalbard and compare them to concentrations found in white whales sampled from that same area 15 years ago. plasma collected from live-captured white whales from two time periods (2013-2014, n = 9, and 1996-2001, n = 11) were analysed for 19 different pfass. the 11 pfass detected included seven c8-c14 perfluoroalkyl carboxylates (pfcas) and ... | 2020 | 32302893 |
| toxoplasma gondii, sarcocystis sp. and neospora caninum-like parasites in seals from northern and eastern canada: potential risk to consumers. | zoonotic parasites of seals that are harvested for food may pose a health risk when seal meat or organ tissues of infected animals are eaten raw or undercooked. in this study, 124 tissue samples from 81 seals, comprising four species, were collected from northern and eastern canada. tissues from 23 ringed seals (pusa hispida), 8 hooded seals (cystophora cristata), 21 harp seals (pagophilus groenlandicus), and 29 grey seals (halichoerus grypus) were tested for parasites of the sarcocystidae famil ... | 2019 | 32095635 |
| accumulation of pbdes in stranded harp (pagophilus groenlandicus) and hooded seals (cystophora cristata) from the northeastern united states. | polybrominated diphenyl ethers (pbdes) are highly lipophilic components of brominated flame retardants that are environmentally persistent and bioaccumulate. pbdes are taken up from the gastrointestinal tract and accumulate mainly in fat depots and liver tissues. seal species inhabiting arctic and sub-arctic regions can have upwards of 30% of their body mass composed of blubber. when those blubber stores are mobilized for energy, stored toxicants are also released into circulation. most studies ... | 2018 | 29706368 |
| the bacterial microbiome in the small intestine of hooded seals (cystophora cristata). | arctic hooded seals (cystophora cristata) are monogastric carnivores that go through extreme fasting and re-feeding in early life. they are born isolated on sea ice; suckle high-fat milk for four days and may then fast for up to one month before they start hunting and feeding on small prey (fish and crustaceans). previous studies of the gut microbiota in pinnipeds have focused on the large intestine, while little data exist on the small intestinal microbiota. in this study, the bacterial microbi ... | 2020 | 33121092 |
| cell culture experiments reveal that high s100b and clusterin levels may convey hypoxia-tolerance to the hooded seal (cystophora cristata) brain. | while the brain of most mammals suffers from irreversible damage after only short periods of low oxygen levels (hypoxia), marine mammals are excellent breath-hold divers that have adapted to hypoxia. in addition to physiological adaptations, such as large oxygen storing capacity and strict oxygen economy during diving, the neurons of the deep-diving hooded seal (cystophora cristata) have an intrinsic tolerance to hypoxia. we aim to understand the molecular basis of this neuronal hypoxia toleranc ... | 2020 | 33002555 |
| effects of a complex contaminant mixture on thyroid hormones in breeding hooded seal mothers and their pups. | there is a general lack of information on the possible effects of perfluoroalkyl substances (pfass) on thyroid hormones (ths) in wildlife species. the effects of pfass, which are known endocrine disruptors, on the th homeostasis in hooded seals (cystophora cristata) have yet to be investigated. previously, correlations were found between plasma thyroid hormone (th) concentrations in hooded seals, and organohalogen contaminants (ohcs) and hydroxyl (oh)-metabolites. because animals are exposed to ... | 2018 | 29729564 |
| hooded seal cystophora cristata foraging areas in the northeast atlantic ocean-investigated using three complementary methods. | identifying environmental characteristics that define the ecological niche of a species is essential to understanding how changes in physical conditions might affect its distribution and other aspects of its ecology. the present study used satellite relay data loggers (srdls) to study habitat use by northeast atlantic hooded seals (n = 20; 9 adult females, 3 adult males, and 8 juveniles). three different methods were used in combination to achieve maximum insight regarding key foraging areas for ... | 2017 | 29211797 |