| further observations on rangiferine brucellosis in alaskan carnivores. | antibodies against rangiferine brucellosis, brucella suis type 4, are commonly found in the serum of various domestic and wild alaskian carnivores which feed on caribou, rangifer tarandus granti, arctic alaska. sled dogs from five native villages on the range of the artic caribou herd, but not from two villages on the the range of the porcupine caribou herd, are commonly infected. wolves (canis lupus) and red foxes (vulpes fulva) are less commonly infected. about 90% of the grizzly bears (ursus ... | 1975 | 1113440 |
| human injury inflicted by grizzly bears. | grizzly bear (ursus arctos horribilis) attacks resulting in human injury and known to have occurred in the national parks of north america were examined. fifty-seven attacks in which 61 persons were injured took place in three national parks in the united states and accounted for 79 percent of the known injuries. the remaining 16 injuries occurred in four canadian national parks. the 77 injured persons gives an injury rate of 1 person per 2 million visitors. | 1970 | 5470717 |
| detection and control of rotavirus infections in zoo animals. | fecal specimens from 15 exotic animal species, with and without diarrhea, were examined for the presence of rotavirus, bacterial enteropathogens, and intestinal parasites. a commercial enzyme-linked immunosorbent assay was used to detect antigens of rotavirus. rotavirus was detected in the feces of 20 (57%) of 35 of the animals, which included addax (addax nasomaculatus), nyala (tragelaphus angasi), saiga (saiga tatarica), white-tailed gnu (connochaetus gnou), greater kudu (tragelaphus strepsice ... | 1983 | 6315660 |
| experimental brucella suis type 4 infections in domestic and wild alaskan carnivores. | beagle dogs were readily infected by 1.3 x 10(8) colony forming units (cfu) of brucella suis type 4 administered either on canned dog food, or intraperitoneally. such infections were afebrile and otherwise asymptomatic and without any obvious gross lesions. inoculation of 10(8) cfu b. suis type 4 intraperitoneally into two gravid wolves (canis lupus) resulted in infections in both animals. about 24 days later they gave birth, apparently at full-term, to two (both alive) and six (two alive and fo ... | 1981 | 7241703 |
| immobilization of coastal grizzly bears with etorphine hydrochloride. | seventeen coastal grizzly bears (ursus arctos horribilis) from southwestern british columbia were captured and immobilized a total of 27 times with etorphine hydrochloride (m99). effective dosages administered ranged from 0.011 to 0.132 mg/kg. drug dosages (on a body weight basis) were not significantly related to induction times (r=-.040); however, it appeared that induction could be reduced with an increased dosage. at higher dosage levels respiratory rate was reduced to 2/minute. | 1980 | 7411738 |
| comparative anatomy of the cardiac foramen ovale in cats (felidae), dogs (canidae), bears (ursidae) and hyaenas (hyaenidae). | the structure of the foramen ovale from 16 species representing 4 carnivore families, the felidae, canidae, ursidae and hyaenidae, was studied using the scanning electron microscope. the felidae were represented by 9 domestic cat fetuses (felis catus), 2 snow leopard neonates (uncia uncia), an ocelot neonate (leopardus pardalis), 2 lion neonates (panthera leo), a panther neonate (panthera pardus) and 3 tigers (neofelis tigris), comprising 2 fetuses and a neonate. the canidae were represented by ... | 1995 | 7649822 |
| serological survey of selected canine viral pathogens and zoonoses in grizzly bears (ursus arctos horribilis) and black bears (ursus americanus) from alaska. | between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (ursus arctos horribilis) and 40 black bears (ursus americanus) from alaska, united states of america, and were tested for selected canine viral infections and zoonoses. antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. in black bears, prevalenc ... | 1998 | 9850547 |
| a retrospective study of dental conditions of captive brown bears (ursus arctos spp.) compared with free-ranging alaskan grizzlies (ursus arctos horribilis). | the teeth of 63 skulls of brown bears (ursus arctos spp.) that had lived in the bernese bear pit between 1850 and 1995 were examined and radiographed for occlusion, loss of teeth, calcified dental plaque and calculus, attrition, and caries. dental pathology and periodontal status were evaluated with respect to age and location in the dentition. further techniques such as computed tomography, microhardness testing, histologic sectioning, and scanning electron microscopy were used in selected case ... | 1999 | 10484135 |
| dietary protein content alters energy expenditure and composition of the mass gain in grizzly bears (ursus arctos horribilis). | many fruits contain high levels of available energy but very low levels of protein and other nutrients. the discrepancy between available energy and protein creates a physiological paradox for many animals consuming high-fruit diets, as they will be protein deficient if they eat to meet their minimum energy requirement. we fed young grizzly bears both high-energy pelleted and fruit diets containing from 1.6% to 15.4% protein to examine the role of diet-induced thermogenesis and fat synthesis in ... | 2003 | 12794679 |
| factors associated with fecal glucocorticoids in alaskan brown bears (ursus arctos horribilis). | the aims of this study were to validate a radioimmunoassay (ria) for quantifying glucocorticoid metabolite concentrations in the feces of alaskan brown bears (ursus arctos horribilis) and to investigate whether any of the following factors are associated with those concentrations: the presence of humans or other bears, fishing difficulty, sex-age class, diet, and season. we tested an established corticosterone ria for assay sensitivity, similarity, precision, and sample matrix effects of brown b ... | 2004 | 15095251 |
| comparison of echocardiography-guided and fluoroscopy-guided endomyocardial biopsy techniques. | the accuracy of bioptome placement for endomyocardial biopsy was evaluated using standard fluoroscopic guidance and compared simultaneously with two-dimensional echocardiography in six healthy subadult grizzly bears (ursus arctos horribilis). despite perceived adequate positioning of the bioptome toward the septum when judged using fluoroscopy, only one out of the six placements were actually positioned in the right ventricular apex toward the septum when evaluated using two-dimensional echocard ... | 2005 | 15869156 |
| persistent organic pollutants in british columbia grizzly bears: consequence of divergent diets. | nitrogen and carbon stable isotope signatures in growing hair reveal that while some british columbia grizzly bears (ursus arctos horribilis) rely entirely on terrestrial foods, others switch in late summer to returning pacific salmon (oncorynchus spp.). implications for persistent organic pollutant (pop) concentrations and patterns measured in the two feeding groups of grizzly bears were profound. while the bears consuming a higher proportion of terrestrial vegetation ("interior" grizzlies) exh ... | 2005 | 16201616 |
| assessment of pesticide residues in army cutworm moths (euxoa auxiliaris) from the greater yellowstone ecosystem and their potential consequences to foraging grizzly bears (ursus arctos horribilis). | during summer, a grizzly bear (ursus arctos horribilis) in the greater yellowstone ecosystem (gye) (usa) can excavate and consume millions of army cutworm moths (euxoa auxiliaris) (acms) that aggregate in high elevation talus. grizzly bears in the gye were listed as threatened by the us fish and wildlife service in 1975 and were proposed for delisting in 2005. however, questions remain about key bear foods. for example, acms are agricultural pests and concern exists about whether they contain pe ... | 2006 | 16487567 |
| hibernation-associated changes in persistent organic pollutant (pop) levels and patterns in british columbia grizzly bears (ursus arctos horribilis). | we hypothesized that depleted fat reserves in grizzly bears (ursus arctos horribilis) following annual hibernation would reveal increases in persistent organic pollutant (pop) concentrations compared to those present in the fall. we obtained fat and hair from british columbia grizzly bears in early spring 2004 to compare with those collected in fall 2003, with the two tissue types providing contaminant and dietary information, respectively. by correcting for the individual feeding habits of griz ... | 2007 | 17410772 |
| decreased bone turnover with balanced resorption and formation prevent cortical bone loss during disuse (hibernation) in grizzly bears (ursus arctos horribilis). | disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. however, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. her ... | 2008 | 18037367 |
| titin isoform switching is a major cardiac adaptive response in hibernating grizzly bears. | the hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. here we studied how hibernating grizzly bears (ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. we evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and hibernating period. because both collagen and titin are involved in altering diastolic function, we investigated both in the my ... | 2008 | 18502907 |
| interthalamic hematoma secondary to cerebrovascular atherosclerosis in an aged grizzly bear (ursus arctos horribilis) with primary cardiac schwannoma. | a 38-year-old intact female grizzly bear (ursus arctos horribilis) was evaluated for progressive seizure activity, pale mucous membranes, deficient pupillary light and menace responses, and irregular shallow respiration. because of poor response to treatment, the animal was euthanized. gross examination revealed abundant hemorrhage in both lateral ventricles; a large, encapsulated mass within the rostral interthalamic region; and a well-demarcated, round white mass in the apex of the right ventr ... | 2008 | 19110714 |
| acquired arteriovenous fistula in a grizzly bear (ursus arctos horribilis). | a captive adult male grizzly bear (ursus arctos horribilis) was evaluated due to multifocal wounds of the skin and subcutaneous tissues sustained as a result of trauma from another grizzly bear. on presentation, one lesion that was located in the perineal region seemed to be a deep puncture with purple tissue protruding from it. this perineal wound did not heal in the same manner or rate as did the other wounds. twenty-five days after initial detection, substantial active hemorrhage from the les ... | 2009 | 19368261 |
| persistent or not persistent? polychlorinated biphenyls are readily depurated by grizzly bears (ursus arctos horribilis). | major pharmacokinetic processes influencing polychlorinated biphenyl (pcb) accumulation in mammals include uptake, biotransformation, respiration, and excretion. we characterized some of the factors underlying pcb accumulation/loss by evaluating pcb concentrations and patterns in pre- and posthibernation grizzly bears (ursus arctos horribilis) and their prey. the pcb congeners with vicinal meta- and para-chlorine unsubstituted hydrogen positions consistently showed loss both before and during hi ... | 2009 | 19480534 |
| grizzly bears (ursus arctos horribilis) and black bears (ursus americanus) prevent trabecular bone loss during disuse (hibernation). | disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. in contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (ursus arct ... | 2009 | 19703606 |
| contrafreeloading in grizzly bears: implications for captive foraging enrichment. | although traditional feeding regimens for captive animals were focused on meeting physiological needs to assure good health, more recently emphasis has also been placed on non-nutritive aspects of feeding. the provision of foraging materials to diversify feeding behavior is a common practice in zoos but selective consumption of foraging enrichment items over more balanced "chow" diets could lead to nutrient imbalance. one alternative is to provide balanced diets in a contrafreeloading paradigm. ... | 2010 | 19816856 |
| cardiac function adaptations in hibernating grizzly bears (ursus arctos horribilis). | research on the cardiovascular physiology of hibernating mammals may provide insight into evolutionary adaptations; however, anesthesia used to handle wild animals may affect the cardiovascular parameters of interest. to overcome these potential biases, we investigated the functional cardiac phenotype of the hibernating grizzly bear (ursus arctos horribilis) during the active, transitional and hibernating phases over a 4 year period in conscious rather than anesthetized bears. the bears were cap ... | 2010 | 19940994 |
| bacterial populations and metabolites in the feces of free roaming and captive grizzly bears. | gut physiology, host phylogeny, and diet determine the composition of the intestinal microbiota. grizzly bears (ursus arctos horribilis) belong to the order carnivora, yet feed on an omnivorous diet. the role of intestinal microflora in grizzly bear digestion has not been investigated. microbiota and microbial activity were analysed from the feces of wild and captive grizzly bears. bacterial composition was determined using culture-dependent and culture-independent methods. the feces of wild and ... | 2009 | 20029525 |
| increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (igf-i) expression accompany low heart rate in hibernating grizzly bears. | grizzly bears (ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. we evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (myhc) isoform expression and expression of a set of genes ... | 2011 | 21117961 |
| energy homeostasis regulatory peptides in hibernating grizzly bears. | grizzly bears (ursus arctos horribilis) are inactive for up to 6months during hibernation. they undergo profound seasonal changes in food intake, body mass, and energy expenditure. the circa-annual regulation of metabolism is poorly understood. in this study, we measured plasma ghrelin, leptin, obestatin, and neuropeptide-y (npy) levels, hormones known to be involved in the regulation of energy homeostasis, in ten grizzly bears. blood samples were collected during the active summer period, early ... | 2010 | 21187098 |
| morphological variability and molecular identification of uncinaria spp. (nematoda: ancylostomatidae) from grizzly and black bears: new species or phenotypic plasticity? | the hookworms uncinaria rauschi olsen, 1968 and uncinaria yukonensis ( wolfgang, 1956 ) were formally described from grizzly ( ursus arctos horribilis) and black bears ( ursus americanus ) of north america. we analyzed the intestinal tracts of 4 grizzly and 9 black bears from alberta and british columbia, canada and isolated uncinaria specimens with anatomical traits never previously documented. we applied morphological and molecular techniques to investigate the taxonomy and phylogeny of these ... | 2015 | 25548982 |
| first report of taenia arctos (cestoda: taeniidae) from grizzly (ursus arctos horribilis) and black bears (ursus americanus) in north america. | the cestode taenia arctos was found at necropsy in the small intestine of a grizzly (ursus arctos horribilis) and a black bear (ursus americanus) from kananaskis country in southwestern alberta, canada. the autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial dna cytochrome c oxidase subunit 1 gene confirmed their identity as t. arctos. this is the first report of t. arctos from definitive hosts in no ... | 2014 | 24382413 |
| using laser ablation inductively coupled plasma mass spectrometry (la-icp-ms) to characterize copper, zinc and mercury along grizzly bear hair providing estimate of diet. | we enhanced an existing technique, laser ablation inductively coupled plasma mass spectrometry (la-icp-ms), to function as a non-lethal tool in the temporal characterization of trace element exposure in wild mammals. mercury (hg), copper (cu), cadmium (cd), lead (pb), iron (fe) and zinc (zn) were analyzed along the hair of captive and wild grizzly bears (ursus arctos horribilis). laser parameters were optimized (consecutive 2000 μm line scans along the middle line of the hair at a speed of 50 μm ... | 2015 | 26005744 |
| grizzly bear (ursus arctos horribilis) locomotion: forelimb joint mechanics across speed in the sagittal and frontal planes. | the majority of terrestrial locomotion studies have focused on parasagittal motion and paid less attention to forces or movement in the frontal plane. our previous research has shown that grizzly bears produce higher medial ground reaction forces (lateral pushing from the animal) than would be expected for an upright mammal, suggesting frontal plane movement may be an important aspect of their locomotion. to examine this, we conducted an inverse dynamics analysis in the sagittal and frontal plan ... | 2017 | 28153978 |
| life in the fat lane: seasonal regulation of insulin sensitivity, food intake, and adipose biology in brown bears. | grizzly bears (ursus arctos horribilis) have evolved remarkable metabolic adaptations including enormous fat accumulation during the active season followed by fasting during hibernation. however, these fluctuations in body mass do not cause the same harmful effects associated with obesity in humans. to better understand these seasonal transitions, we performed insulin and glucose tolerance tests in captive grizzly bears, characterized the annual profiles of circulating adipokines, and tested the ... | 2017 | 27987017 |
| expert judgment and uncertainty regarding the protection of imperiled species. | decisions concerning the appropriate listing status of species under the u.s. endangered species act (esa) can be controversial even among conservationists. these decisions may determine whether a species persists in the near term and have long-lasting social and political ramifications. given the esa's mandate that such decisions be based on the best available science, it is important to examine what factors contribute to experts' judgments concerning the listing of species. we examined how a v ... | 2017 | 27624752 |
| removal of lipid from serum increases coherence between brucellosis rapid agglutination test and enzyme-linked immunosorbent assay in bears in alaska, usa. | in cases of chronic brucella spp. infection, results of the rose bengal plate test (rbpt) and indirect enzyme-linked immunosorbent assay (elisa) should be coherent, as reported in controlled conditions in the literature. we compared rbpt and elisa results in 58 alaska grizzly bears ( ursus arctos horribilis), eight kodiak brown bears ( ursus arctos middendorffi), and six alaska peninsula brown bears ( ursus arctos gyas). of the 72 bears tested, 42 (58%) were elisa positive and 53 (73%) were rbpt ... | 2016 | 27458833 |
| ecology of conflict: marine food supply affects human-wildlife interactions on land. | human-wildlife conflicts impose considerable costs to people and wildlife worldwide. most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. we tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (ursus arctos horribilis) conflict, using data from british columbia, canada, between 1960-2014. we found most support for the limited f ... | 2016 | 27185189 |
| positive reinforcement training for blood collection in grizzly bears (ursus arctos horribilis) results in undetectable elevations in serum cortisol levels: a preliminary investigation. | training nonhuman animals in captivity for participation in routine husbandry procedures is believed to produce a lower stress environment compared with undergoing a general anesthetic event for the same procedure. this hypothesis rests largely on anecdotal evidence that the captive subjects appear more relaxed with the trained event. blood markers of physiological stress responses were evaluated in 4 captive grizzly bears (ursus arctos horribilis) who were clicker-trained for blood collection v ... | 2016 | 26847149 |
| medulloblastoma in a grizzly bear (ursus arctos horriblis). | a 3-yr-old female spayed grizzly bear (ursus arctos horribilis) was evaluated for seizure activity along with lethargy, inappetence, dull mentation, and aggressive behavior. magnetic resonance (mr) examination of the brain revealed a contrast-enhanced right cerebellar mass with multifocal smaller nodules located in the left cerebellum, thalamus, hippocampus, and cerebrum with resultant obstructive hydrocephalus. cerebrospinal fluid analysis revealed mild mononuclear pleocytosis, with differentia ... | 2015 | 26352975 |
| grizzly bear (ursus arctos horribilis) locomotion: gaits and ground reaction forces. | locomotion of plantigrade generalists has been relatively little studied compared with more specialised postures even though plantigrady is ancestral among quadrupeds. bears (ursidae) are a representative family for plantigrade carnivorans, they have the majority of the morphological characteristics identified for plantigrade species, and they have the full range of generalist behaviours. this study compared the locomotion of adult grizzly bears (ursus arctos horribilis linnaeus 1758), including ... | 2015 | 26254319 |
| indigenous knowledge and science unite to reveal spatial and temporal dimensions of distributional shift in wildlife of conservation concern. | range shifts among wildlife can occur rapidly and impose cascading ecological, economic, and cultural consequences. however, occurrence data used to define distributional limits derived from scientific approaches are often outdated for wide ranging and elusive species, especially in remote environments. accordingly, our aim was to amalgamate indigenous and western scientific evidence of grizzly bear (ursus arctos horribilis) records and detail a potential range shift on the central coast of brit ... | 2014 | 25054635 |
| confronting uncertainty in wildlife management: performance of grizzly bear management. | scientific management of wildlife requires confronting the complexities of natural and social systems. uncertainty poses a central problem. whereas the importance of considering uncertainty has been widely discussed, studies of the effects of unaddressed uncertainty on real management systems have been rare. we examined the effects of outcome uncertainty and components of biological uncertainty on hunt management performance, illustrated with grizzly bears (ursus arctos horribilis) in british co ... | 2013 | 24223134 |
| validation of a novel cognitive bias task based on difference in quantity of reinforcement for assessing environmental enrichment. | cognitive bias tasks purport to assess affective states via responses to ambiguous stimuli. we hypothesized that a novel cognitive bias task based on positive reinforcement using quantity differences would detect changes in affect in captive grizzly bears (ursus arctos horribilis). we trained bears (n = 8) to respond differently (nose or paw touch) to two stimuli (light or dark gray cue cards), with responses counterbalanced across bears. the two cues signaled a small or large food reward, respe ... | 2014 | 24045850 |
| plant consumption by grizzly bears reduces biomagnification of salmon-derived polychlorinated biphenyls, polybrominated diphenyl ethers, and organochlorine pesticides. | the present study characterizes the uptake and loss of persistent organic pollutants (pops) in grizzly bears (ursus arctos horribilis) by sampling and analyzing their terrestrial and marine foods and fecal material from a remote coastal watershed in british columbia, canada. the authors estimate that grizzly bears consume 341 to 1,120 µg of polychlorinated biphenyls (pcbs) and 3.9 to 33 µg of polybrominated diphenyl ethers daily in the fall when they have access to an abundant supply of returnin ... | 2013 | 23401324 |
| spinal cord compression in two related ursus arctos horribilis. | two 15-yr-old grizzly bear littermates were evaluated within 9 mo of each other with the symptom of acute onset of progressive paraparesis and proprioceptive ataxia. the most significant clinical examination finding was pelvic limb paresis in both bears. magnetic resonance examinations of both bears showed cranial thoracic spinal cord compression. the first bear had left-sided extradural, dorsolateral spinal cord compression at t3-t4. vertebral canal stenosis was also observed at t2-t3. images o ... | 2012 | 23082524 |
| human perspectives and conservation of grizzly bears in banff national park, canada. | some conservation initiatives provoke intense conflict among stakeholders. the need for action, the nature of the conservation measures, and the effects of these measures on human interests may be disputed. tools are needed to depolarize such situations, foster understanding of the perspectives of people involved, and find common ground. we used q methodology to explore stakeholders' perspectives on conservation and management of grizzly bears (ursus arctos horribilis) in banff national park and ... | 2012 | 22594593 |
| disseminated pleomorphic myofibrosarcoma in a grizzly bear (ursus arctos horribilis). | the pathological and diagnostic features of a widely disseminated pleomorphic high-grade myofibroblastic sarcoma are described in a 23-year-old male brown bear (ursus arctos horribilis). firm, solid, white to tan neoplastic nodules, often with cavitated or soft grey-red necrotic centres, were observed throughout most internal organs, subcutaneous tissues and skeletal muscles on gross examination. microscopically, the tumour consisted of pleomorphic spindle cells forming interlacing fascicles wit ... | 2012 | 22297075 |
| constraints on herbivory by grizzly bears. | although well known as carnivores and not capable of digesting plant fiber, grizzly bears (ursus arctos horribilis) consume over 200 species of plants and are entirely vegetarian in some ecosystems. even in ecosystems with abundant meat resources, green vegetation can be an important seasonal food resource. therefore, we examined the morphological, physiological, and environmental constraints that determine the nutritional value of herbaceous vegetation to grizzly bears. short-term, board foragi ... | 2001 | 28547091 |