Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| metastrongyloid nematode (otostrongylus circumlitus) infection in a stranded california sea lion (zalophus californianus)--a new host-parasite association. | a stranded yearling male california sea lion was admitted to a rehabilitation center june 2003. on presentation, the sea lion was emaciated and had diarrhea and neutrophilia. two weeks later, the animal became anorexic, blood and mucus were observed around the oral cavity, and corneal opacity was noted in the right eye. hematology results at that time included leukocytosis consisting of neutrophilia with a left shift, anemia, and thrombocytopenia. despite supportive care, the sea lion died. on p ... | 2005 | 16244070 |
| aerobic bacterial flora of the nasal cavity in gulf of california sea lion (zalophus californianus) pups. | nasal swab samples from clinically healthy california sea lions pups (zalophus californianus) from six different reproductive rookeries in the gulf of california were collected to determine the type and frequency of the representative aerobic bacterial microflora of their nasal mucosa. a total of 114 samples were examined and 100 bacterial isolates were identified and typified by microbiological and biochemical standard tests. fifty four isolates corresponded to gram positive bacteria (54%) and ... | 2005 | 16266850 |
| pathology of domoic acid toxicity in california sea lions (zalophus californianus). | over 100 free-ranging adult california sea lions (zalophus californianus) and one northern fur seal (callorhinus ursinus), predominantly adult females, were intoxicated by domoic acid (da) during three harmful algal blooms between 1998 and 2000 in central and northern california coastal waters. the vector prey item was northern anchovy (engraulis mordax) and the primary da-producing algal diatom was psuedonitzschia australis. postmortem examination revealed gross and histologic findings that wer ... | 2005 | 15753472 |
| leptospirosis in northern elephant seals (mirounga angustirostris) stranded along the california coast. | leptospirosis was identified in six northern elephant seals (mirounga angustirostris) that were stranded in 1995 along the coast of california (usa). histologic lesions in all seals included tubulointerstitial nephritis with tubular degeneration and necrosis. infection was confirmed through identification of spirochetes using an immunohistochemical stain for leptospira sp. antigens. one affected seal had an elevated titer to leptospira interrogans serovar pomona. four of the six seals developed ... | 2005 | 16107678 |
| molecular phylogenetics and diagnosis of anisakis, pseudoterranova, and contracaecum from northern pacific marine mammals. | individual specimens of anisakis, pseudoterranova, and contracaecum collected from marine mammals inhabiting northern pacific waters were used for comparative diagnostic and molecular phylogenetic analyses. forty-eight new sequences were obtained for this study of 14 anisakis taxa, 8 pseudoterranova taxa, 4 contracaecum taxa, and 4 outgroup species. partial 28s (lsu) and complete internal transcribed spacer (its-1, 5.8s, its-2) ribosomal dna was amplified by the polymerase chain reaction and seq ... | 2005 | 16539026 |
| pcbs and ddt in the serum of juvenile california sea lions: associations with vitamins a and e and thyroid hormones. | top-trophic predators like california sea lions bioaccumulate high levels of persistent fat-soluble pollutants that may provoke physiological impairments such as endocrine or vitamins a and e disruption. we measured circulating levels of polychlorinated biphenyls (pcbs) and dichlorodiphenyltrichloroethane (ddt) in 12 healthy juvenile california sea lions captured on año nuevo island, california, in 2002. we investigated the relationship between the contamination by pcbs and ddt and the circulati ... | 2005 | 15589659 |
| the development of the pulmonary surfactant system in california sea lions. | pulmonary surfactant has previously been shown to change during development, both in composition and function. adult pinnipeds, unlike adult terrestrial mammals, have an altered lung physiology to cope with the high pressures associated with deep diving. here, we investigated how surfactant composition and function develop in california sea lions (zalophus californianus). phosphatidylinositol was the major anionic phospholipid in the newborn, whereas phosphatidylglycerol was increased in the adu ... | 2005 | 15964230 |
| photomicrographic images of some features of uncinaria spp (nematoda: ancylostomatidae) from otariid pinnipeds. | photomicrographs of several morphologic features of hookworms (uncinaria spp) from northern fur seal (callorhinus ursinus) and california sea lion (zalophus californianus) pups are presented. the main purpose is to show and describe some physical characteristics of hookworms from the two hosts; it is not to decide from these attributes whether the uncinaria spp are the same species. the number of species of uncinaria in pinnipeds is uncertain and specimens need to be examined from the various in ... | 2005 | 15719261 |
| localization of aerial pure tones by pinnipeds. | in this study, minimum audible angles (maas) of aerial pure tones were measured in and compared between a northern elephant seal (mirounga angustirostris), a harbor seal (phoca vitulina), and a california sea lion (zalophus californianus). testing was conducted between 0.8 and 16 khz in the elephant seal and 0.8 and 20 khz in the harbor seal and sea lion in a hemi-anechoic chamber using a left/right psychophysical procedure. performance for the same frequencies was also quantified for discrete s ... | 2005 | 16419834 |
| underwater temporary threshold shift in pinnipeds: effects of noise level and duration. | behavioral psychophysical techniques were used to evaluate the residual effects of underwater noise on the hearing sensitivity of three pinnipeds: a california sea lion (zalophus californianus), a harbor seal (phoca vitulina), and a northern elephant seal (mirounga angustirostris). temporary threshold shift (tts), defined as the difference between auditory thresholds obtained before and after noise exposure, was assessed. the subjects were exposed to octave-band noise centered at 2500 hz at two ... | 2005 | 16334695 |
| identifying and quantifying prey consumption using stomach temperature change in pinnipeds. | for many marine predators knowledge of foraging behavior is limited to inferences based on changes in diving or movement patterns at sea. this results in an incomplete and potentially inaccurate view of the foraging ecology of a species. this study examined the use of stomach temperature telemetry to identify and quantify prey consumed in both a phocid (northern elephant seal mirounga angustirostris) and an otariid (california sea lion zalophus californianus) species. in addition, we used opport ... | 2006 | 17079722 |
| isoflurane anaesthesia in four sea lions (otaria byronia and zalophus californianus). | to (1) evaluate a purpose-built chamber for inducing isoflurane anaesthesia in sea lions and (2) assess isoflurane as an anaesthetic for dental surgery in these species. | 2006 | 16916352 |
| killer whales are capable of vocal learning. | the production learning of vocalizations by manipulation of the sound production organs to alter the physical structure of sound has been demonstrated in only a few mammals. in this natural experiment, we document the vocal behaviour of two juvenile killer whales, orcinus orca, separated from their natal pods, which are the only cases of dispersal seen during the three decades of observation of their populations. we find mimicry of california sea lion (zalophus californianus) barks, demonstratin ... | 2006 | 17148275 |
| pathology and preliminary characterization of a parapoxvirus isolated from a california sea lion (zalophus californianus). | cutaneous pox-like lesions are a common complication in the rehabilitation of pinnipeds. however, the exact identity, taxonomy, and host range of pinniped parapoxviruses remain unknown. during a poxvirus outbreak in may 2003 in california sea lions (zalophus californianus) at a marine mammal rehabilitation facility, multiple raised, firm, 1-3-cm skin nodules from the head, neck, and thorax of one sea lion weanling pup that spontaneously died were collected. histologically, the nodules were chara ... | 2006 | 16699145 |
| lesions associated with a novel mycoplasma sp. in california sea lions (zalophus californianus) undergoing rehabilitation. | from july 1999 to november 2001, mycoplasma sp. was cultured from lesions in 16 california sea lions (zalophus californianus) undergoing rehabilitation. the mycoplasma sp. was the likely cause of death of four animals in which it was associated with either pneumonia or polyarthritis. the most common lesion associated with this bacterium was subdermal abscessation, found in 12 animals. other lesions included intramuscular abscesses, septic arthritis, and lymphadenopathy. infection was associated ... | 2006 | 16699147 |
| seroepidemiology of parapoxvirus infections in captive and free-ranging california sea lions zalophus californianus. | cutaneous nodular lesions caused by parapoxvirus infections are commonly observed in stranded pinnipeds following their arrival at rehabilitation facilities. an indirect enzyme-linked immunosorbent assay (elisa) was developed and validated to determine exposure to parapoxviruses in california sea lions zalophus californianus in captivity and in the wild. the diagnostic performance of this assay was evaluated using receiver-operating characteristic analysis. at a selected cut-off value, the calcu ... | 2006 | 16724559 |
| the evolution of a physiological system: the pulmonary surfactant system in diving mammals. | pulmonary surfactant lines the alveolar air-water interface, varying surface tension with lung volume to increase compliance and prevent adhesion of respiratory surfaces. we examined whether the surfactant system of diving mammals exhibits adaptations for more efficient lung function during diving, to complement other respiratory adaptations. here we review adaptations at the molecular, compositional, functional and cellular levels and during development for animals beginning life on land and pr ... | 2006 | 16877052 |
| otarine herpesvirus-1, not papillomavirus, is associated with endemic tumours in california sea lions (zalophus californianus). | the purpose of this study was to determine if otarine herpesvirus-1 (othv-1) is associated with the presence of urogenital carcinomas in california sea lions. polymerase chain reaction (pcr) analysis with primers specific for othv-1 was used to compare the prevalence of othv-1 infection in 15 sea lions affected by urogenital carcinoma with that of age-matched and juvenile tumour-free animals, and animals with tumours of non-urogenital origin. the herpesvirus was more prevalent (100%) and more wi ... | 2006 | 17034810 |
| marine mammal neoplasia: a review. | a review of the published literature indicates that marine mammal neoplasia includes the types and distributions of tumors seen in domestic species. a routine collection of samples from marine mammal species is hampered, and, hence, the literature is principally composed of reports from early whaling expeditions, captive zoo mammals, and epizootics that affect larger numbers of animals from a specific geographic location. the latter instances are most important, because many of these long-lived, ... | 2006 | 17099143 |
| the composition of pulmonary surfactant from diving mammals. | maintaining a functional pulmonary surfactant system at depth is critical for diving mammals to ensure that inspiration is possible upon re-emergence. the lipid and protein composition of lavage extracts from three pinniped species (california sea lion, northern elephant seal and ringed seal) were compared to several terrestrial species. lavage samples were purified using a nabr discontinuous gradient. concentrations of phospholipid classes and molecular species were measured using electrospray ... | 2006 | 16140043 |
| california sea lions (zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern baja california, méxico, than in california, usa. | chlorinated hydrocarbons (chs) were determined in blubber samples of 18 california sea lions (zalophus californianus californianus) that stranded dead along todos santos bay, ensenada, baja california, méxico, january 2000-november 2001. summation operatorddts were the dominant group (geometric mean 3.8 microg/g lipid weight), followed by polychlorinated biphenyls ( summation operatorpcbs, 2.96 microg/g), chlordanes (0.12 microg/g) and hexachlorocyclohexanes (0.06 microg/g). the summation operat ... | 2006 | 16297516 |
| aerobic bacterial flora of the vagina and prepuce of california sea lions (zalophus californianus) and investigation of associations with urogenital carcinoma. | to investigate the association between genital bacterial infection and urogenital carcinoma in california sea lions (zalophus californianus), vaginal and preputial swabs for bacterial isolation were taken from 148 free-ranging and 51 stranded california sea lions including 16 animals with urogenital carcinoma. cytological examination of vaginal or preputial smears showed a majority (65.5%, 57/87) of animals examined had mild or no inflammation. aerobic bacteria were isolated from 116 (78.4%) wil ... | 2006 | 16326045 |
| the surface activity of pulmonary surfactant from diving mammals. | pinnipeds (seals and sea lions) have developed a specialised respiratory system to cope with living in a marine environment. they have a highly reinforced lung that can completely collapse and reinflate during diving without any apparent side effects. these animals may also have a specialised surfactant system to augment the morphological adaptations. the surface activity of surfactant from four species of pinniped (california sea lion, northern elephant seal, northern fur seal and ringed seal) ... | 2006 | 16476655 |
| an analysis of visual oddity concept learning in a california sea lion (zalophus californianus). | we tested a california sea lion for visual oddity learning by presentingproblems composed ofthree two-dimensional black-and-white stimuli, two identical (s-) and one different (s+). in the first experimental stage, a single problem per session was presented until learning criterion was reached. in the second experimental stage, all problems were presented only five times in succession; then a new problem was introduced (six problems/session). in the third experimental stage, each problem was pre ... | 2006 | 16933800 |
| contrasting effects of heterozygosity on survival and hookworm resistance in california sea lion pups. | low genetic heterozygosity is associated with loss of fitness in many natural populations. however, it remains unclear whether the mechanism is related to general (i.e. inbreeding) or local effects, in particular from a subset of loci lying close to genes under balancing selection. here we analyse involving heterozygosity-fitness correlations on neonatal survival of california sea lions and on susceptibility to hookworm (uncinaria spp.) infection, the single most important cause of pup mortality ... | 2006 | 16689912 |
| lateralised swimming behaviour in the california sea lion. | lateralised motor behaviour in the pinnipeds has been subject to little investigation. this study examined the swimming behaviour of seven zoo-housed california sea lions to determine whether they exhibited a directional bias in their motor behaviour. data were collected on the direction of the animals' swimming patterns from the point of entering a pool of water from dry land. each animal was studied for 100 episodes of swimming. all seven of the sea lions showed significant (p<0.001) bias in t ... | 2006 | 16682155 |
| mhc gene configuration variation in geographically disparate populations of california sea lions (zalophus californianus). | major histocompatibility complex (mhc) class ii drb genotypes were examined in two geographically isolated populations of california sea lions (zalophus californianus) (gulf of california and california coastal pacific ocean). genomic dna from 227 california sea lions was examined using eight sequence-specific primer (ssp) pairs flanking the putative peptide-binding site. a total of 40 different zaca-drb genotype configurations were identified among the 227 individuals. using ssp-pcr, significan ... | 2006 | 16448418 |
| evaluation of two different biomarkers for use in the assessment of toxic chemical exposure in california sea lions (zalophus californianus). | 2006 | 16298399 | |
| determination of hbcd, pbdes and meo-bdes in california sea lions (zalophus californianus) stranded between 1993 and 2003. | blubber samples from male california sea lions (zalphophus californianus) stranded between 1993 and 2003 were analyzed for 27 polybrominated diphenyl ether (pbde) congeners, three isomers of hexabromocyclododecane (hbcd) and 14 methoxylated polybrominated diphenyl ether (meo-bde) congeners. total pbdes ranged from 450 ng/g to 4740 ng/g wet mass and total hbcd ranged from < 0.3 ng/g to 12 ng/g wet mass. the concentration of hbcd increased from 0.7 ng/g to12.0 ng/g wet mass in sea lion blubber bet ... | 2006 | 16293266 |
| onset, growth, and recovery of in-air temporary threshold shift in a california sea lion (zalophus californianus). | a california sea lion (zalophus californianus) was tested in a behavioral procedure to assess noise-induced temporary threshold shift (tts) in air. octave band fatiguing noise was varied in both duration (1.5-50 min) and level (94-133 db re 20 mupa) to generate a variety of equal sound exposure level conditions. hearing thresholds were measured at the center frequency of the noise (2500 hz) before, immediately after, and 24 h following exposure. threshold shifts generated from 192 exposures rang ... | 2007 | 18189581 |
| galápagos and californian sea lions are separate species: genetic analysis of the genus zalophus and its implications for conservation management. | accurate formal taxonomic designations are thought to be of critical importance for the conservation of endangered taxa. the galápagos sea lion (gsl), being appreciated as a key element of the galápagos marine ecosystem, has lately been listed as 'vulnerable' by the iucn. to date there is, however, hardly any scientific evidence, whether it constitutes a separate entity from its abundant californian neighbour (csl). in this paper, we delineate the taxonomic relationships within the genus zalophu ... | 2007 | 17868473 |
| hookworm enteritis with bacteremia in california sea lion pups on san miguel island. | large breeding populations of california sea lions (zalophus californianus) are located on san miguel and san nicolas islands in the southern california bight. in 2001, there was a substantial increase in pup mortality in late summer and fall. from june 2002 to january 2003, 208 freshly dead pups were examined on san miguel island, the most western of the channel islands off the coast of southern california. tissues from 186 of these pups were examined histologically. the primary lesions in 133 ... | 2007 | 17495302 |
| relation of dental wear to the concentrations of essential minerals in teeth of the california sea lion zalophus californianus californianus. | tooth wear in marine mammals has been attributed to age, feeding habits, behavior, and contaminants. advanced tooth wear in some california sea lions, including some of very young age (<5 yr), in the gulf of california, suggests that there are variations in chemical composition of tooth parts, wherein the concentrations of certain trace minerals might be anomalous, making them more susceptible to erosion. the concentrations of the essential minerals ca, p, k, na, fe, mg, and zn in the dentition ... | 2007 | 17435255 |
| ancient dna analysis of the japanese sea lion (zalophus californianus japonicus peters, 1866): preliminary results using mitochondrial control-region sequences. | in this study, we successfully extracted ancient dna from skeletal remains of the japanese sea lion-a species that is practically extinct-from archaeological sites and determined a partial sequence of its mitochondrial dna control region. a molecular phylogenetic tree constructed by the neighbor-joining (nj) method showed that the sequences from japanese sea lions clustered together, with a high bootstrap value, and that this cluster was closest to the california sea lion cluster. the distinctly ... | 2007 | 17409720 |
| spatial release from masking of aerial tones in pinnipeds. | in most masking experiments, target signals and sound intended to mask are located in the same position. spatial release from masking (srm) occurs when signals and maskers are spatially separated, resulting in detection improvement relative to when they are spatially co-located. in this study, srm was investigated in a harbor seal, who naturally lacks pinnae, and california sea lion, who possesses reduced pinnae. subjects had to detect aerial tones at 1, 8, and 16 khz in the presence of octave b ... | 2007 | 17348543 |
| transplacental transfer of organochlorines in california sea lions (zalophus californianus). | the transplacental transfer of organochlorines (ocs) in california sea lions (zalophus californianus) was investigated by analyzing blubber samples from 20 female sea lions and their fetuses during the last trimester of pregnancy. a rapid, high-performance liquid chromatographic, photodiode-array method was used to measure blubber concentrations of polychlorinated biphenyls (pcbs), including dioxin-like congeners, as well as ddts and hexachlorobenzene. summed values of pcbs (sigmapcbs), of ddts ... | 2007 | 17269457 |
| total body oxygen stores and physiological diving capacity of california sea lions as a function of sex and age. | a defining physiological capability for air-breathing marine vertebrates is the amount of oxygen that can be stored in tissues and made available during dives. to evaluate the influence of oxygen storage capacity on aerobic diving capacity, we examined the extent to which blood and muscle oxygen stores varied as a function of age, body size and sex in the sexually dimorphic california sea lion, zalophus californianus. we measured total body oxygen stores, including hematocrit, hemoglobin, mchc, ... | 2007 | 17210964 |
| tissue heavy metal concentrations of stranded california sea lions (zalophus californianus) in southern california. | concentrations of nine heavy metals (as, cd, cu, fe, hg, pb, mn, mo and zn) were determined in the hepatic and renal tissues of 80 stranded california sea lions (zalophus californianus). significant age-dependant increases were observed in liver and kidney concentrations of cadmium and mercury, and renal zinc concentrations. hepatic iron concentrations were significantly higher in females than males. animals with suspected domoic acid associated pathological findings had significantly higher con ... | 2007 | 17116350 |
| cyclical changes in seroprevalence of leptospirosis in california sea lions: endemic and epidemic disease in one host species? | leptospirosis is a zoonotic disease infecting a broad range of mammalian hosts, and is re-emerging globally. california sea lions (zalophus californianus) have experienced recurrent outbreaks of leptospirosis since 1970, but it is unknown whether the pathogen persists in the sea lion population or is introduced repeatedly from external reservoirs. | 2007 | 17986335 |
| maternal-fetal transfer of domoic acid in rats at two gestational time points. | prenatal exposure to asymptomatic doses of domoic acid (da) causes learning and memory deficits later in life; therefore, we sought to measure distribution of da in maternal plasma and brain, prenatal brain, and amniotic fluid 1 hr after exposure, a time frame that normally encompasses acute seizure behavior. | 2007 | 18087593 |
| age-prevalence of otarine herpesvirus-1, a tumor-associated virus, and possibility of its sexual transmission in california sea lions. | otarine herpesvirus-1 (othv-1) is a gammaherpesvirus routinely detected in urogenital tumor tissues of adult sea lions dying during rehabilitation, to investigate the epidemiology of this virus and guide the development of a mathematical model of its role in the multifactorial etiology of cancer in california sea lions, polymerase chain reaction (pcr) amplification of an othv-1 specific fragment of the dna polymerase gene was used to look for evidence of othv-1 infection in urogenital and pharyn ... | 2007 | 17208394 |
| sexing pinnipeds with zfx and zfy loci. | we developed and tested a protocol for determining the sex of individual pinnipeds using the sex-chromosome-specific genes zfx and zfy. we screened a total of 368 seals (168 crabeater, lobodon carcinophaga; 159 weddell, leptonychotes weddellii; and 41 ross, ommatophoca rossii) of known or unknown sex and compared the molecular sex to the sex assigned at the time of biopsy sample collection in the ross and amundsen seas, antarctica. we also screened 6 captive northern elephant seals (mirounga ang ... | 2007 | 17548861 |
| urate nephrolithiasis in a northern elephant seal (mirounga angustirostris) and a california sea lion (zalophus californianus). | nephrolithiasis has rarely been reported in marine mammals. during 2004 and 2005, two cases of nephrolithiasis were diagnosed during routine necropsy examination, one in a northern elephant seal (mirounga angustirostris) and one in a california sea lion (zalophus californianus). nephroliths were found throughout both kidneys during necropsy examination, varying in size from 1-10 mm in diameter in the northern elephant seal and from 1-15 mm in diameter in the california sea lion. necropsy and his ... | 2007 | 17469285 |
| contaminants still high in top-level carnivores in the southern california bight: levels of ddt and pcbs in resident and transient pinnipeds. | highly industrialized areas, such as the southern california bight, often have high levels of contaminants in marine sediments, which can cause chronic exposure to organisms long after their use has ceased. tddt and tpcb were analyzed in the blubber of 145 stranded pinnipeds that died at local marine mammal centers between 1994 and 2006. resident species (california sea lion and pacific harbor seal) had significantly higher concentrations of tddt and tpcb than the transient species (northern ele ... | 2008 | 18835609 |
| distribution of tissue enzymes in three species of pinnipeds. | in domestic animal medicine, changes in serum enzyme levels are routinely used as diagnostic tools to detect liver disease. hepatic disease occurs in pinnipeds, but limited data are available on the tissue distribution of serum enzymes in marine mammals. the objectives of this study were to determine the tissue distribution of seven serum enzymes in three pinniped species. enzymes evaluated were alanine aminotransferase (alt), aspartate aminotransferase (ast), sorbitol dehydrogenase (sdh), lacta ... | 2008 | 18432090 |
| intraperitoneal implantation of life-long telemetry transmitters in otariids. | pinnipeds, including many endangered and declining species, are inaccessible and difficult to monitor for extended periods using externally attached telemetry devices that are shed during the annual molt. archival satellite transmitters were implanted intraperitoneally into four rehabilitated california sea lions (zalophus californianus) and 15 wild juvenile steller sea lions (eumetopias jubatus) to determine the viability of this surgical technique for the deployment of long-term telemetry devi ... | 2008 | 19077193 |
| monitoring glucocorticoid response to rehabilitation and research procedures in california and steller sea lions. | we used serum and fecal corticosteroid analysis to study the physiological response to a range of invasive and non-invasive procedures in sea lions. four experimental groups of california sea lions (zalophus californianus; group a: restraint only [n=9], group b: gas anesthesia without surgery [n=10], group c: minimally invasive surgery [n=10], and group d: invasive surgery [n=5]) were monitored for adrenal response. feces were collected opportunistically from 72 hr before 72 hr post procedure fo ... | 2008 | 18172847 |
| estimating sustainable bycatch rates for california sea lion populations in the gulf of california. | commercial and subsistence fisheries pressure is increasing in the gulf of california, mexico. one consequence often associated with high levels of fishing pressure is an increase in bycatch of marine mammals and birds. fisheries bycatch has contributed to declines in several pinniped species and may be affecting the california sea lion (zalophus californianus) population in the gulf of california. we used data on fisheries and sea lion entanglement in gill nets to estimate current fishing press ... | 2008 | 18410402 |
| in vitro susceptibility of sea lion poxvirus to cidofovir. | parapoxviruses of seals and sea lions are commonly encountered pathogens with zoonotic potential. the antiviral activity of the antiviral compounds isatin-beta-thiosemicarbazone, rifampicin, acyclovir, cidofovir and phosphonoacetic acid against a parapoxvirus (slpv-1) isolated from a californian sea lions (zalophus californianus) was evaluated. cidofovir was able to reduce virus-induced cytopathic effect of slpv-1 in confluent monolayers when used in concentrations greater than 2microg/ml. a dec ... | 2008 | 18485494 |
| a noninvasive demographic assessment of sea lions based on stage-specific abundances. | a pressing need exists to develop new approaches for obtaining information on demographic rates without causing further threats to imperiled animal populations. in this paper, we illustrate and apply a data-fitting technique based on quadratic programming that uses stage-specific abundance data to estimate demographic rates and asymptotic population growth rates (lambda). we used data from seven breeding colonies of california sea lions (zalophus californianus) in the gulf of california, mexico. ... | 2008 | 18686587 |
| in utero domoic acid toxicity: a fetal basis to adult disease in the california sea lion (zalophus californianus). | california sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late february through mid-may in association with organochlorine (pcb and ddt) poisoning and infectious disease in the 1970's and domoic acid poisoning in the last decade. the mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month ... | 2008 | 18728728 |
| prevalence and characterization of salmonella spp. among marine animals in the channel islands, california. | salmonella enterica is a zoonotic pathogen that has been isolated from free-ranging marine mammals throughout the world, with animals in the channel islands of california (usa) showing the highest prevalence. the goal of this study was to determine prevalence, antimicrobial sensitivity and genetic similarity using pulsed-field gel electrophoresis (pfge) of salmonella in several non-domestic animal species on san miguel and san nicolas islands. fecal samples were collected from 90 california sea ... | 2008 | 18828559 |
| risk factors for an outbreak of leptospirosis in california sea lions (zalophus californianus) in california, 2004. | leptospirosis has been reported in california sea lions (zalophus californianus) since 1970; however, the source of infection and mode of transmission remain unknown. to elucidate these features, demographic and environmental risk factors for leptospirosis were evaluated. california sea lion stranding records from northern california for 2004 were used to identify cases of leptospirosis (n = 316) and controls (n = 143). demographic characteristics (age class, sex) and environmental factors, repr ... | 2008 | 18957639 |
| novel symptomatology and changing epidemiology of domoic acid toxicosis in california sea lions (zalophus californianus): an increasing risk to marine mammal health. | harmful algal blooms are increasing worldwide, including those of pseudo-nitzschia spp. producing domoic acid off the california coast. this neurotoxin was first shown to cause mortality of marine mammals in 1998. a decade of monitoring california sea lion (zalophus californianus) health since then has indicated that changes in the symptomatology and epidemiology of domoic acid toxicosis in this species are associated with the increase in toxigenic blooms. two separate clinical syndromes now exi ... | 2008 | 18006409 |
| determination of a sedative protocol for use in california sea lions (zalophus californianus) with neurologic abnormalities undergoing electroencephalographic examination. | sedation in sea lions exhibiting abnormal neurologic signs may require modification of established sedatior protocols because of the likely interaction between effects of the sedative and physiologic changes in diseased animals the effects of two sedative combinations, 0.07 mg/kg medetomidine and 0.07 mg/kg medetomidine plus 0.2 mg/kg butorphanol, were compared between california sea lions (zalophus californianus) with signs of neurologic dysfunctior (n=33) and without neurologic signs (n=8). se ... | 2008 | 19110694 |
| a behaviorally explicit demographic model integrating habitat selection and population dynamics in california sea lions. | although there has been a call for the integration of behavioral ecology and conservation biology, there are few tools currently available to achieve this integration. explicitly including information about behavioral strategies in population viability analyses may enhance the ability of conservation biologists to understand and estimate patterns of extinction risk. nevertheless, most behavioral-based pva approaches require detailed individual-based data that are rarely available for imperiled s ... | 2008 | 18680502 |
| trace metal concentrations in the hair of zalophus californianus pups and their relation to feeding habits. | the levels of six trace metals (hg, se, pb, cu, fe, and zn) were measured in the hair of california sea lion pups from eight rookeries in the gulf of california, with the aim of relating these levels with the animals feeding habits, trophic level, and delta(15)n signatures at each locality. trace metal levels were seen to vary significantly between sample sites as were tendencies associated with feeding habits. mercury concentrations showed a clear positive correlation with trophic level (r = 0. ... | 2008 | 18679589 |
| secondary amyloidosis and renal failure in a captive california sea lion (zalophus californianus). | a 16-yr-old, captive-born, female california sea lion (zalophus californianus) was evaluated for intermittent lethargy, partial anorexia, and polydipsia of 2 wk duration. the animal was immobilized for physical examination. it was in thin body condition, with multifocal mucosal ulcerations over the caudal and ventral tongue. blood was collected for hematology, serum chemistry, and leptospirosis serology. serum chemistry revealed severe azotemia, mild hyperglycemia, and severe hyperphosphatemia. ... | 2008 | 18634224 |
| changes in blubber contaminant concentrations in california sea lions (zalophus californianus) associated with weight loss and gain during rehabilitation. | california sea lions have high levels of persistent organic pollutants (pops) in their blubber. animals affected by domoic acid fast and refeed during their rehabilitation. we studied the effect of decreases in total body mass (16 +/- 7% of initial body mass) on blubber pop contaminant concentrations and estimated pop burdens during fasting (12 +/- 5 days) in 19 california sea lions. the effect of refeeding (92 +/- 8% of initial body mass) was also investigated. significant increases in the conc ... | 2008 | 18589985 |
| chronic pancreatitis with secondary diabetes mellitus treated by use of insulin in an adult california sea lion. | a 21-year-old neutered male captive california sea lion developed chronic polyuria; polydipsia; polyphagia; accelerated development of existing cataracts; and frequent episodes of gastrointestinal upset including anorexia, signs of abdominal discomfort, diarrhea, and vomiting. | 2008 | 18518815 |
| neuronal migration defect: a case of subcortical heterotopia in a california sea lion. | a 2 and a half-year-old male california sea lion (zalophus californianus) presented with a history of intermittent generalized seizures. magnetic resonance imaging revealed a large focal mass occupying the right cerebral hemisphere with moderate dilatation of the contralateral lateral ventricle. at necropsy, the right cerebral hemispheric white matter was expanded by numerous irregularly shaped, pale pink nodules up to 10 mm in diameter. the overlying cortex was characterized by increased number ... | 2008 | 18487504 |
| the effects of water temperature on the energetic costs of juvenile and adult california sea lions (zalophus californianus): the importance of skeletal muscle thermogenesis for thermal balance. | as highly mobile marine predators, many pinniped species routinely encounter a wide range of water temperatures during foraging and in association with seasonal, geographical and climatic changes. to determine how such variation in environmental temperature may impact energetic costs in otariids, we determined the thermal neutral zone of adult and juvenile california sea lions (zalophus californianus) by measuring resting metabolic rate using open-flow respirometry. five adult female (body mass ... | 2009 | 19946075 |
| normal morphology and hormone receptor expression in the male california sea lion (zalophus californianus) genital tract. | histomorphology and estrogen alpha (er alpha), and progesterone receptor (pr) expression were evaluated in free-ranging stranded male california sea lions (zalophus californianus). hormone receptor expression was evaluated using an immunohistochemical technique with monoclonal antibodies. estrogen and prs were identified in the efferent ductules, prostate gland, corpus cavernosa, corpus spongiosium, penile urethra, and in the epithelium and stroma of both the penis and prepuce. in some tissues, ... | 2009 | 19768750 |
| the normal genital tract of the female california sea lion (zalophus californianus): cyclic changes in histomorphology and hormone receptor distribution. | changes in reproductive tract histomorphology, and estrogen (eralpha) and progesterone receptor (pr) expression throughout the breeding cycle were evaluated in free-ranging stranded female california sea lions (zalophus californianus). hormone receptor expression in the ovaries, uterus, cervix, and vagina was evaluated using an immunohistochemical technique with monoclonal antibodies. during a large portion of the cycle, ovaries contained both a corpora lutea (cl) and follicles in varying stages ... | 2009 | 19768749 |
| neuroanatomy and volumes of brain structures of a live california sea lion (zalophus californianus) from magnetic resonance images. | the california sea lion (zalophus californianus) has been a focal point for sensory, communication, cognition, and neurological disease studies in marine mammals. however, as a scientific community, we lack a noninvasive approach to investigate the anatomy and size of brain structures in this species and other free-ranging, live marine mammals. in this article, we provide the first anatomically labeled, magnetic resonance imaging-based atlas derived from a live marine mammal, the california sea ... | 2009 | 19768743 |
| hookworm infection, anaemia and genetic variability of the new zealand sea lion. | hookworms are intestinal blood-feeding nematodes that parasitize and cause high levels of mortality in a wide range of mammals, including otariid pinnipeds. recently, an empirical study showed that inbreeding (assessed by individual measures of multi-locus heterozygosity) is associated with hookworm-related mortality of california sea lions. if inbreeding increases susceptibility to hookworms, effects would expectedly be stronger in small, fragmented populations. we tested this assumption in the ... | 2009 | 19605394 |
| tumor morphology and immunohistochemical expression of estrogen receptor, progesterone receptor, p53, and ki67 in urogenital carcinomas of california sea lions (zalophus californianus). | metastatic carcinoma of urogenital origin is a common cause of mortality in free-ranging california sea lions (zalophus californianus). the etiology of this cancer is likely multifactorial, with viral infection, genetic factors, and exposure to environmental organochlorine contaminants possible contributing factors. in this study, expression of estrogen receptor alpha (er alpha), progesterone receptor (pr), p53, and ki67 were evaluated by immunohistochemistry in 12 sea lions with metastatic carc ... | 2009 | 19276047 |
| the role of domoic acid in abortion and premature parturition of california sea lions (zalophus californianus) on san miguel island, california. | domoic acid is a glutaminergic neurotoxin produced by marine algae such as pseudo-nitzschia australis. california sea lions (zalophus californianus) ingest the toxin when foraging on planktivorous fish. adult females comprise 60% of stranded animals admitted for rehabilitation due to acute domoic acid toxicosis and commonly suffer from reproductive failure, including abortions and premature live births. domoic acid has been shown to cross the placenta exposing the fetus to the toxin. to determin ... | 2009 | 19204339 |
| pathological features of amyloidosis in stranded california sea lions (zalophus californianus). | amyloidosis was diagnosed in 26 stranded adult california sea lions between 1983 and 2006 by retrospective case analysis. the kidneys (92.3% of animals), blood vessels (80.7%) and thyroid glands (65.4%) were most commonly affected. macroscopically, affected kidneys were swollen, with pale tan cortices and loss of corticomedullary differentiation. amyloid deposits in the kidney were located in the glomeruli, blood vessels, and peritubular interstitium, most prominently in the outer stripe of the ... | 2009 | 19114281 |
| characterization of a degenerative cardiomyopathy associated with domoic acid toxicity in california sea lions (zalophus californianus). | domoic acid, produced by marine algae, can cause acute and chronic neurologic sequela in california sea lions (zalophus californianus) from acute toxicity or sublethal exposure. eight sea lions, representing acute and chronic cases, both sexes, and all age classes, were selected to demonstrate a concurrent degenerative cardiomyopathy. critical aspects of characterizing the cardiomyopathy by lesion distribution and morphology were the development of a heart dissection and tissue-trimming protocol ... | 2009 | 19112124 |
| pinniped phylogenetic relationships inferred using aflp markers. | amplified fragment length polymorphisms (aflps) are widely used for phylogenetic reconstruction in plants but their use in animal taxa has been limited, and in mammals rare. in addition, their use has been largely limited to shallow relationships amongst species or subspecies. here, we genotype 23 pinniped species for 310 aflp markers and find a strong phylogenetic signal, with individuals coclustering within species, and overall a good agreement between our phylogeny and those constructed using ... | 2009 | 19277054 |
| geographical dissemination of leptospira interrogans serovar pomona during seasonal migration of california sea lions. | leptospirosis is one of the most widespread bacterial zoonoses in the world and affects most mammalian species. although leptospirosis is well documented and characterized in terrestrial species, less information is available regarding the distribution and impact of leptospirosis in marine mammals. additionally, the role of animal migrations on the geographical spread of leptospirosis has not been reported. periodic epizootic outbreaks of acute leptospirosis among california sea lions (zalophus ... | 2009 | 19186009 |
| variable nucleotide tandem-repeat analysis revealing a unique group of leptospira interrogans serovar pomona isolates associated with california sea lions. | leptospira interrogans serovar pomona isolates were compared by variable nucleotide tandem-repeat typing. most cattle isolates grouped together, while isolates from pigs and wildlife were distributed across several groups. significantly, california sea lion isolates formed a unique group, providing evidence that these animals are maintenance hosts of serovar pomona. | 2009 | 19204099 |
| isolation by distance among california sea lion populations in mexico: redefining management stocks. | understanding the spatial structure of a population is critical for effective assessment and management. however, direct observation of spatial dynamics is generally difficult, particularly for marine mammals. california sea lions (zalophus californianus) are polygynous pinnipeds distributed along the pacific coast of north america. the species' range has been subdivided into three management stocks based on differences in mitochondrial dna, but to date no studies have considered nuclear genetic ... | 2009 | 19226320 |
| novel anellovirus discovered from a mortality event of captive california sea lions. | a viral metagenomic study was performed to investigate potential viral pathogens associated with a mortality event of three captive california sea lions (zalophus californianus). this study identified a novel california sea lion anellovirus (zcav), with 35 % amino acid identity in the orf1 region to feline anelloviruses. the double-stranded replicative form of zcav was detected in lung tissue, suggesting that zcav replicates in sea lion lungs. specific pcr revealed the presence of zcav in the lu ... | 2009 | 19264590 |
| organochlorine pesticides and polychlorinated biphenyls in california sea lions (zalophus californianus californianus) from the gulf of california, méxico. | we report concentrations of several classes of organochlorines (ocs) in the blubber of california sea lions (zalophus californianus) from the gulf of california. summed oc levels measured in 34 wild-ranging animals were, in general, lower than those previously reported in sea lions from the eastern pacific. the rank order of ocs was sigmaddts (mean=3400 ng g(-1 ) lipid weight [lw]) > sigmapcbs (1400 ng g(-1 ) lw) > sigmahchs (50 ng g(-1 ) lw) >or= sigmachlors (46 ng g(-1 ) lw). the most abundant ... | 2009 | 18560925 |
| ddt exposure of zebrafish embryos enhances seizure susceptibility: relationship to fetal p,p'-dde burden and domoic acid exposure of california sea lions. | california sea lions have a large body burden of organochlorine pesticides, and over the last decade they have also been subject to domoic acid poisoning. domoic acid poisoning, previously recognized in adult animals, is now viewed as a major cause of prenatal mortality. the appearance of a chronic juvenile domoic acid disease in the sea lions, characterized by behavioral abnormalities and epilepsy, is consistent with early life poisoning and may be potentiated by organochlorine burden. | 2009 | 19165389 |
| association of an unusual marine mammal mortality event with pseudo-nitzschia spp. blooms along the southern california coastline. | during 2002, 2,239 marine mammals stranded in southern california. this unusual marine mammal stranding event was clustered from april to june and consisted primarily of california sea lions (zalophus californianus) and long-beaked common dolphins (delphinus capensis) with severe neurologic signs. intoxication with domoic acid (da), a marine neurotoxin produced during seasonal blooms of pseudo-nitzschia spp., was suspected. definitively linking harmful algal blooms to large-scale marine mammal m ... | 2009 | 19204340 |
| entanglements of marine mammals and seabirds in central california and the north-west coast of the united states 2001-2005. | entanglement records for seabirds and marine mammals were investigated for the period 2001-2005. the entanglement records were extracted from databases maintained by seven organizations operating along the west coast of the united states of america. their programmes included beach monitoring surveys, rescue and rehabilitation and regional pinniped censuses. records of 454 entanglements were documented in live animals and in carcasses for 31 bird species and nine marine mammal species. the most f ... | 2009 | 19344921 |
| fishing gear-related injury in california marine wildlife. | we reviewed medical records from select wildlife rehabilitation facilities in california to determine the prevalence of injury in california brown pelicans (pelecanus occidentalis), gulls (larus spp.), and pinniped species (zalophus californianus, mirounga angustirostris, and phoca vitulina) due to fishing gear entanglement and ingestion from 2001 to 2006. of 9,668 brown pelican, gull, and pinniped cases described during the 6-yr study period (2001-06), 1,090 (11.3%) were fishing gear-related. p ... | 2009 | 19395745 |
| polybrominated diphenyl ethers in pinnipeds stranded along the southern california coast. | little to no information exists for polybrominated diphenyl ethers (pbdes) in marine mammals frequenting the highly urbanized southern california (usa) coast. fourteen pbde congeners were determined by gc-ecni-ms in blubber of pinnipeds stranded locally between 1994 and 2006. total pbde concentrations (sigmapbde) in california sea lion (n = 63) ranged from 0.04 to 33.7 microg/g wet weight (mean: 5.24 microg/g). to our knowledge, these are the highest reported pbde levels in marine mammals to dat ... | 2009 | 19487060 |
| risk factors associated with cataracts and lens luxations in captive pinnipeds in the united states and the bahamas. | to determine risk factors for lens luxation and cataracts in captive pinnipeds in the united states and the bahamas. | 2010 | 20707754 |
| marine mammal blubber reference and control materials for use in the determination of halogenated organic compounds and fatty acids. | the national institute of standards and technology (nist) has a diverse collection of control materials derived from marine mammal blubber, fat, and serum. standard reference material (srm) 1945 organics in whale blubber was recertified for polychlorinated biphenyl (pcb) congeners, organochlorine pesticides, and polybrominated diphenyl ether (pbde) congeners. srm 1945 has also been assigned mass fraction values for compounds not frequently determined in marine samples including toxaphene congene ... | 2010 | 20238106 |
| characterization of trpc2, an essential genetic component of vns chemoreception, provides insights into the evolution of pheromonal olfaction in secondary-adapted marine mammals. | pheromones are chemical cues released and sensed by individuals of the same species, which are of major importance in regulating reproductive and social behaviors of mammals. generally, they are detected by the vomeronasal system (vns). here, we first investigated and compared an essential genetic component of vomeronasal chemoreception, that is, trpc2 gene, of four marine mammals varying the degree of aquatic specialization and related terrestrial species in order to provide insights into the e ... | 2010 | 20142439 |
| immunomodulatory effects upon in vitro exposure of california sea lion and southern sea otter peripheral blood leukocytes to domoic acid. | during red tide bloom events, the marine diatom pseudo-nitzschia produces the toxin domoic acid (da), which has been associated with stranding and mortality events involving california sea lions (zalophus californianus) and southern sea otters (enhydra lutris). in addition to these well-documented da-induced neurotoxic events, there is increasing concern that da may exert chronic effects, such as immunomodulation, which may potentially increase an individual's susceptibility to a number of oppor ... | 2010 | 20688647 |
| psychophysical and electrophysiological aerial audiograms of a steller sea lion (eumetopias jubatus). | a within-subject comparison of auditory steady-state response (assr) and psychophysical measurements of aerial hearing sensitivity was conducted with an individual of the largest otariid species, the steller sea lion. psychophysical methods were used to obtain an unmasked aerial audiogram at 13 frequencies, spanning a range of 0.125-34 khz. the subject had a hearing range (frequencies audible at 60 db(rms) re 20 micropa) of about 0.250-30 khz, and a region of best hearing sensitivity from 5-14.1 ... | 2010 | 20370049 |
| characterization of progressive keratitis in otariids. | to characterize a form of progressive keratitis that occurs commonly in otariids. | 2010 | 20840090 |
| accuracy of argos locations of pinnipeds at-sea estimated using fastloc gps. | argos satellite telemetry is one of the most widely used methods to track the movements of free-ranging marine and terrestrial animals and is fundamental to studies of foraging ecology, migratory behavior and habitat-use. argos location estimates do not include complete error estimations, and for many marine organisms, the most commonly acquired locations (location class 0, a, b, or z) are provided with no declared error estimate. | 2010 | 20090942 |
| pleuritis and suppurative pneumonia associated with a hypermucoviscosity phenotype of klebsiella pneumoniae in california sea lions (zalophus californianus). | the aim of this study is to document the isolation of a hypermucoviscosity (hmv) phenotype of klebsiella pneumoniae from 25 cases of suppurative pneumonia and pleuritis and two cases of abscesses in california sea lions (zalophus californianus) from the central california coast, representing the first report of this zoonotic pathogen from the marine environment and only the second report in non-humans. animals died 2h to 4 days after first being observed sick on beaches. clinical signs varied fr ... | 2010 | 19709820 |
| characterization of phylogenetically diverse astroviruses of marine mammals. | astroviruses are small, non-enveloped, positive-stranded rna viruses. previously studied mammalian astroviruses have been associated with diarrhoeal disease. knowledge of astrovirus diversity is very limited, with only six officially recognized astrovirus species from mammalian hosts and, in addition, one human and some bat astroviruses were recently described. we used consensus pcr techniques for initial identification of five astroviruses of marine mammals: three from california sea lions (zal ... | 2010 | 19759240 |
| characterization of san miguel sea lion virus populations using pyrosequencing-based methods. | san miguel sea lion virus (smsv) is a small rna virus in the genus vesivirus with an unusually broad host range. three populations of smsv were examined by pcr amplification of the capsid precursor and putative helicase genes, followed by pyrosequencing. the populations were nasal swabs from two smsv infected california sea lions (zalophus californianus) from two different years, and a virus isolate from the earlier swab that was passaged in cell culture five times. in the capsid precursor, exte ... | 2010 | 19931646 |
| identification of the expressed mhc class ii dqb gene of the asiatic black bear, ursus thibetanus, in japan. | genetic diversity estimation of the major histocompatibility complex (mhc) gene may be an important tool in the assessment of immune response ability against infectious disease. we were able to identify a near full-length expressed dqb sequence by race-pcr method from the asiatic black bear, ursus thibetanus in japan. this is the first such full length expression in the ursidae. the bear had at least one functional dqb locus. in phylogenetic tree analysis its dqb amino acid sequence formed a mon ... | 2010 | 20558901 |
| cloning and characterization of glutamate receptors in californian sea lions (zalophus californianus). | domoic acid produced by marine algae has been shown to cause acute and chronic neurologic sequelae in californian sea lions following acute or low-dose exposure. histological findings in affected animals included a degenerative cardiomyopathy that was hypothesized to be caused by over-excitation of the glutamate receptors (glurs) speculated to be present in the sea lion heart. thus tissues from five sea lions without lesions associated with domoic acid toxicity and one animal with domoic acid-in ... | 2010 | 20559490 |
| polyomavirus infection in a free-ranging california sea lion (zalophus californianus) with intestinal t-cell lymphoma. | an adult female california sea lion (zalophus californianus) that stranded in central california was found to have a small glossal polypoid mass on gross necropsy. histologically, the mass was consistent with a fibropapilloma, and intranuclear inclusions were found within endothelial cells lining small arterioles within the mass. electron microscopy revealed 40-nm virions within endothelial intranuclear inclusions. rolling circle amplification was used to obtain a partial viral genomic sequence. ... | 2010 | 20622238 |
| standardized protocols for plasma clearance of iohexol are not appropriate for determination of glomerular filtration rates in anesthetized california sea lions (zalophus californianus). | abstract: plasma clearance of iohexol was evaluated in eight anesthetized california sea lions (zalophus californianus), without evidence of renal dysfunction, to determine if the one-compartment model and the sample protocol used in dogs and cats could be applied to this species. nonlinearity between samples in 75% (6/8) of sea lions voided those results. an additional two anesthetized sea lions were sampled at 5, 30, 45, 60, 120, 180, 240, and 360 min post iohexol injection and semi-logarithmi ... | 2010 | 20722269 |
| phylogenetic analysis of marine mammal herpesviruses. | five novel dna-dependent dna polymerase (dpol) herpesviral sequences were generated using nested consensus polymerase chain reaction (pcr) in clinical samples from a harbor seal (phoca vitulina), bottlenose dolphin (tursiops truncatus), orca (orcinus orca), california sea lion (zalophus californianus), and a phocid herpesvirus 2 (phhv-2) isolate from a harbor seal (used as positive control). these novel sequences and other representative herpesvirus sequences were included in bayesian and maximu ... | 2010 | 21055885 |
| novel hemotrophic mycoplasma identified in naturally infected california sea lions (zalophus californianus). | the hemoplasmas are the trivial name for a group of erythrocyte-parasitizing, non-cultivable in vitro bacteria of the genus mycoplasma that have been described in several mammalian hosts worldwide. this study is the first report of hemoplasmas in marine mammals. edta anticoagulated whole blood samples from 137 california sea lions (zalophus californianus) and 20 northern elephant seals (mirounga angustirostris) admitted to the marine mammal center (sausalito, ca; www.marinemammalcenter.org) or l ... | 2010 | 21111543 |
| magnetic resonance imaging quality and volumes of brain structures from live and postmortem imaging of california sea lions with clinical signs of domoic acid toxicosis. | our goal in this study was to compare magnetic resonance images and volumes of brain structures obtained alive versus postmortem of california sea lions zalophus californianus exhibiting clinical signs of domoic acid (da) toxicosis and those exhibiting normal behavior. proton density-(pd) and t2-weighted images of postmortem-intact brains, up to 48 h after death, provided similar quality to images acquired from live sea lions. volumes of gray matter (gm) and white matter (wm) of the cerebral hem ... | 2010 | 21133324 |
| acoustic characteristics of ultrasonic coded transmitters for fishery applications: could marine mammals hear them? | ultrasonic coded transmitters (ucts) producing frequencies of 69-83 khz are used increasingly to track fish and invertebrates in coastal and estuarine waters. to address concerns that they might be audible to marine mammals, acoustic properties of ucts were measured off mission beach, san diego, and at the u.s. navy transdec facility. a regression model fitted to vemco uct data yielded an estimated source level of 147 db re 1 μpa spl @ 1 m and spreading constant of 14.0. based on transdec measur ... | 2010 | 21110617 |
| first evidence for adoption in california sea lions. | demographic parameters such as birth and death rates determine the persistence of populations. understanding the mechanisms that influence these rates is essential to developing effective management strategies. alloparental behavior, or the care of non-filial young, has been documented in many species and has been shown to influence offspring survival. however, the role of alloparental behavior in maintaining population viability has not been previously studied. here, we provide the first eviden ... | 2010 | 21079727 |