Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| debilitation and mortality associated with besnoitiosis in four virginia opossums (didelphis virginiana). | besnoitia spp. are coccidian parasites that infect a variety of wild and domestic mammals as well as some reptiles. although infection with besnoitia is common in virginia opossums (didelphis virginiana), clinical signs or death due to besnoitia is rare. this manuscript describes four virginia opossums that had severe clinical disease and inflammation associated with besnoitiosis. clinical signs included trembling, incoordination, circling, blindness, poor body condition, and sudden death. gross ... | 2012 | 22779243 |
| two pathogens and one disease: detection and identification of flea-borne rickettsiae in areas endemic for murine typhus in california. | results of an environmental assessment conducted in a newly emergent focus of murine typhus in southern california are described. opossums, didelphis virginiana kerr, infested with cat fleas, ctenocephalides felis buché, in the suburban area were abundant. animal and flea specimens were tested for the dna of two flea-borne rickettsiae, rickettsia typhi and rickettsia felis. r. felis was commonly detected in fleas collected throughout this area while r. typhi was found at a much lower prevalence ... | 2012 | 23270180 |
| endogenous lipid pneumonia in opossums from louisiana. | endogenous lipid pneumonia was present in 19 of 27 opossums (didelphis virginiana) trapped in the vicinity of baton rouge, louisiana. the severity of lesions varied from small pleural and subpleural aggregates of foamy macrophages with minimal disruption of pulmonary architecture to large nodular accumulations of foam cells with cholesterol clefts and localized emphysema. the cause of the lipid pneumonia may be related to pulmonary nematode parasite infections, which were evident in 13 of the af ... | 2012 | 3373627 |
| induced renal dysplasia in the young pouch opossum. | using the north american opossum, didelphis virginiana, we have developed a new model for studying the effects of early fetal urinary obstruction on subsequent renal development. we have successfully induced renal dysplasia in the marsupial that has a typically mammalian kidney. | 2011 | 3236178 |
| efferent projections of the basolateral amygdala in the opossum, didelphis virginiana. | the autoradiographic anterograde axonal transport technique was used to study efferent projections of the opossum basolateral amygdala. all nuclei of the basolateral amygdala send topographically organized fibers to the bed nucleus of the stria terminalis (bst) via the stria terminalis (st). injections into rostrolateral portions of the basal nuclei label fibers that surround the commissural bundle of the st, cross the midline by passing along the outer aspect of the anterior commissure, and ter ... | 2011 | 3768738 |
| tick-borne disease agents in various wildlife from mississippi. | because tick-borne diseases are becoming increasingly important throughout the world, monitoring their causative agents in wildlife may serve as a useful indicator of potential human exposure. we assessed the presence of known and putative zoonotic, tick-borne agents in four wildlife species in mississippi. animals were tested for exposure to or infection with ehrlichia chaffeensis, ehrlichia ewingii, borrelia lonestari, rickettsia spp., anaplasma phagocytophilum, and francisella tularensis. who ... | 2011 | 20846016 |
| invasive plant species alters consumer behavior by providing refuge from predation. | understanding the effects of invasive plants on native consumers is important because consumer-mediated indirect effects have the potential to alter the dynamics of coexistence in native communities. invasive plants may promote changes in consumer pressure due to changes in protective cover (i.e., the architectural complexity of the invaded habitat) and in food availability (i.e., subsidies of fruits and seeds). no experimental studies have evaluated the relative interplay of these two effects. ... | 2011 | 21221650 |
| serological response of cats to experimental besnoitia darlingi and besnoitia neotomofelis infections and prevalence of antibodies to these parasites in cats from virginia and pennsylvania. | abstract besnoitia darlingi and besnoitia neotomofelis are cyst-forming tissue apicomplexan parasites that use domestic cats ( felis domesticus ) as definitive hosts and opossums ( didelphis virginiana ) and southern plains woodrats ( neotoma micropus ) as intermediate hosts, respectively. nothing is known about the prevalence of b. darlingi or b. neotomofelis in cats from the united states. besnoitia darlingi infections have been reported in naturally infected opossums from many states in the u ... | 2011 | 21506782 |
| structure of parasite component communities of didelphid marsupials: insights from a comparative study. | abstract the parasite fauna of the gray four eyed opossum and the common opossum in camp du tigre, french guiana is herein characterized. nine species from the gastrointestinal system were recovered from both species, which shared 80% of their parasites. the parasite fauna comprised several monoxenous species (63%) and was dominated by a. raillieti, which exhibited high levels of prevalence and abundance in both communities. only 2 species (moennigia sp. and spirura guianensis) had been recorded ... | 2011 | 21506798 |
| novel hepatozoon in vertebrates from the southern united states. | abstract novel hepatozoon spp. sequences collected from previously unrecognized vertebrate hosts in north america were compared with documented hepatozoon 18s rrna sequences in an effort to examine phylogenetic relationships between the different hepatozoon organisms found cycling in nature. an approximately 500 base pair fragment of 18s rdna common to hepatozoon spp. and some other apicomplexans was amplified and sequenced from the tissues or blood of 16 vertebrate host species from the souther ... | 2011 | 21506825 |
| femoral loading mechanics in the virginia opossum, didelphis virginiana: torsion and mediolateral bending in mammalian locomotion. | studies of limb bone loading in terrestrial mammals have typically found anteroposterior bending to be the primary loading regime, with torsion contributing minimally. however, previous studies have focused on large, cursorial eutherian species in which the limbs are held essentially upright. recent in vivo strain data from the virginia opossum (didelphis virginiana), a marsupial that uses a crouched rather than an upright limb posture, have indicated that its femur experiences appreciable torsi ... | 2011 | 21957109 |
| in vivo strains in the femur of the virginia opossum (didelphis virginiana) during terrestrial locomotion: testing hypotheses of evolutionary shifts in mammalian bone loading and design. | terrestrial locomotion can impose substantial loads on vertebrate limbs. previous studies have shown that limb bones from cursorial species of eutherian mammals experience high bending loads with minimal torsion, whereas the limb bones of non-avian reptiles (and amphibians) exhibit considerable torsion in addition to bending. it has been hypothesized that these differences in loading regime are related to the difference in limb posture between upright mammals and sprawling reptiles, and that the ... | 2011 | 21753057 |
| cone pigments in a north american marsupial, the opossum (didelphis virginiana). | only two of the four cone opsin gene families found in vertebrates are represented in contemporary eutherian and marsupial species. recent genetic studies of two species of south american marsupial detected the presence of representatives from two of the classes of cone opsin genes and the structures of these genes predicted cone pigments with respective peaks in the ultraviolet and long-wavelength portions of the spectrum. the virginia opossum (didelphis virginiana), a profoundly nocturnal anim ... | 2010 | 20224889 |
| ontogeny of the oestrogen receptors esr1 and esr2 during gonadal development in the tammar wallaby, macropus eugenii. | oestrogen has wide ranging effects in development mediated mainly via the two oestrogen receptors, alpha (esr1, also known as eralpha) and beta (esr2, also known as erbeta). oestrogen is the key factor that directs the indifferent gonad to become an ovary in many non-mammalian vertebrates. oestrogen is not required for early ovarian differentiation in mammals but can disrupt normal testicular development in eutherians. surprisingly, exogenous oestrogen can cause sex reversal of an xy gonad in tw ... | 2010 | 20028801 |
| seasonal changes in the physiology of male virginia opossums (didelphis virginiana): signs of the dasyurid semelparity syndrome? | semelparity, which is multiplying once in a lifetime, is a rare reproductive strategy among mammals. several species of the marsupial family dasyuridae experience 100% male mortality following an intense mating period. we investigated seasonal physiological changes that may be associated with early mortality in the male virginia opossum (didelphis virginiana; didelphidae) and compared these changes with those of semelparous, male dasyurids. free-ranging male virginia opossums (n=36) were collect ... | 2010 | 12905127 |
| a genetic analysis of the virginia opossum mating system: evidence of multiple paternity in a highly fragmented landscape. | using molecular techniques, we examined patterns of paternity in virginia opossums occupying a highly fragmented agricultural landscape in northern indiana. during 2008, we collected tissue from 64 females and their pouch young in 34 forest patches distributed over a 1100-km(2) region. using genotypes from 10 microsatellite loci, we determined the minimum number of fathers contributing to each litter using gerud 1.0. genotyped offspring with known mothers were then analyzed using cervus 3.0, inc ... | 2010 | 19995804 |
| dna barcodes effectively identify the morphologically similar common opossum (didelphis marsupialis) and virginia opossum (didelphis virginiana) from areas of sympatry in mexico. | two morphologically similar species of opossum from the genus didelphis-didelphis virginiana and didelphis marsupialis-cooccur sympatrically in mexico. high intraspecific variation complicates their morphological discrimination, under both field and museum conditions. this study aims to evaluate the utility and reliability of using dna barcodes (short standardized genome fragments used for dna-based identification) to distinguish these two species. sequences of the cytochrome c oxidase subunit i ... | 2010 | 21271858 |
| evaluation of a rapid immunochromatographic dipstick test for detection of antibodies to trypanosoma cruzi in dogs experimentally infected with isolates obtained from opossums (didelphis virginiana), armadillos (dasypus novemcinctus), and dogs (canis familiaris) from the united states. | dogs are reservoir hosts for trypanosoma cruzi , the causative agent of american trypanosomiasis. a rapid immunochromatographic dipstick test (ict) is available commercially for canine serological testing. the ict was developed with the use of sera from south american dogs, but it is not routinely used in the united states. we evaluated the utility of the ict in detecting anti-t. cruzi antibodies in dogs from the united states. dogs (n = 64) were experimentally infected with united states' iso ... | 2010 | 21348621 |
| structure and expression of two nuclear receptor genes in marsupials: insights into the evolution of the antisense overlap between the α-thyroid hormone receptor and rev-erbα. | alternative processing of α-thyroid hormone receptor (trα, nr1a1) mrnas gives rise to two functionally antagonistic nuclear receptors: trα1, the α-type receptor, and trα2, a non-hormone binding variant that is found only in mammals. trα2 shares an unusual antisense coding overlap with mrna for rev-erbα (nr1d1), another nuclear receptor protein. in this study we examine the structure and expression of these genes in the gray short-tailed opossum, monodelphis domestica, in comparison with that of ... | 2010 | 21143985 |
| prevalence of antibodies to trypanosoma cruzi, toxoplasma gondii, encephalitozoon cuniculi, sarcocystis neurona, besnoitia darlingi, and neospora caninum in north american opossums, didelphis virginiana, from southern louisiana. | we examined the prevalence of antibodies to zoonotic protozoan parasites ( trypanosoma cruzi, toxoplasma gondii, and encephalitozoon cuniculi) and protozoans of veterinary importance ( neospora caninum, sarcocystis neurona, and besnoitia darlingi) in a population of north american opossums ( didelphis virginiana) from louisiana. samples from 30 opossums were collected as part of a survey for t. cruzi in louisiana. frozen sera from these 30 opossums were examined using an indirect immunofluoresce ... | 2010 | 21158620 |
| seroprevalence of trypanosoma cruzi among eleven potential reservoir species from six states across the southern united states. | trypanosoma cruzi, the causative agent of chagas' disease, is a substantial public health concern in latin america. although rare in humans and domestic animals in the united states, t. cruzi is commonly detected in some wildlife species, most commonly raccoons (procyon lotor) and virginia opossums (didelphis virginiana). to increase our understanding of the reservoir host species range and geographic distribution, 11 species of mammals from six states spanning the known range of t. cruzi (arizo ... | 2010 | 20020815 |
| experimental infection of didelphis marsupialis with vesicular stomatitis new jersey virus. | although vesicular stomatitis has been present for many years in the americas, many aspects of its natural history remain undefined. in this study, we challenged five adult virginia opossums (didelphis marsupialis) with vesicular stomatitis new jersey serotype virus (vsnjv). opossums had no detectable antibodies against vsnjv prior to being inoculated with 10(6.5) median tissue culture infective doses (tcid(50)) of vsnjv by two routes; intraepithelial/subepithelial (ie/se) inoculation and scarif ... | 2010 | 20090034 |
| experimental infection of two south american reservoirs with four distinct strains of trypanosoma cruzi. | trypanosoma cruzi (tc), the causative agent of chagas disease, is a diverse species with 2 primary genotypes, tci and tcii, with tcii further subdivided into 5 subtypes (iia-e). this study evaluated infection dynamics of 4 genetically and geographically diverse t. cruzi strains in 2 south american reservoirs, degus (octodon degus) and grey short-tailed opossums (monodelphis domestica). based on prior suggestions of a genotype-host association, we hypothesized that degus (placental) would more re ... | 2010 | 20128943 |
| molecular characterization of sarcocystis neurona strains from opossums (didelphis virginiana) and intermediate hosts from central california. | sarcocystis neurona is a significant cause of neurological disease in horses and other animals, including the threatened southern sea otter (enhydra lutris nereis). opossums (didelphis virginiana), the only known definitive hosts for s. neurona in north america, are an introduced species in california. s. neurona dna isolated from sporocysts and/or infected tissues of 10 opossums, 6 horses, 1 cat, 23 southern sea otters, and 1 harbor porpoise (phocoena phocoena) with natural infections was analy ... | 2010 | 20226596 |
| intrahepatic growth and maturation of gnathostoma turgidum in the natural definitive opossum host, didelphis virginiana. | gnathostoma turgidum is a gastric nematode parasite of opossums found in the americas. we recently found that g. turgidum juveniles appear in the liver of the opossums where they become mature adults and almost synchronously move to the stomach during certain months of the year, suggesting the importance of the liver for the growth and maturation of this species in the final hosts. in this study we attempted to detect g. turgidum larvae in the liver of opossums, didelphis virginiana that are the ... | 2010 | 20447468 |
| trypanosoma cruzi i genotypes in different geographical regions and transmission cycles based on a microsatellite motif of the intergenic spacer of spliced-leader genes. | the intergenic region of spliced-leader (sl-ir) genes from 105 trypanosoma cruzi i (tc i) infected biological samples, culture isolates and stocks from 11 endemic countries, from argentina to the usa were characterised, allowing identification of 76 genotypes with 54 polymorphic sites from 123 aligned sequences. on the basis of the microsatellite motif proposed by herrera et al. (2007) to define four haplotypes in colombia, we could classify these genotypes into four distinct tc i sl-ir groups, ... | 2010 | 20670628 |
| epizootiologic survey of mycobacterium bovis in wildlife and farm environments in northern michigan. | bovine tuberculosis (bovine tb), caused by mycobacterium bovis, has reemerged in northern michigan, usa, with detections in white-tailed deer (odocoileus virginianus) in 1994 and in cattle in 1998. since then, significant efforts have been directed toward reducing deer densities in the area in the hopes of reducing the bovine tb prevalence rate in deer and eliminating spillover of the disease into cattle. despite the success of the efforts to reduce deer densities, additional cattle herds have b ... | 2010 | 20688630 |
| prevalence and risk factors associated with sarcocystis neurona infections in opossums (didelphis virginiana) from central california. | sarcocystis neurona, a protozoal parasite shed by opossums (didelphis virginiana), has been shown to cause significant morbidity and mortality in horses, sea otters, and other marine mammals. over the course of 3 years (fall 2005-summer 2008), opossums from central california were tested for infection with s. neurona. of 288 opossums sampled, 17 (5.9%) were infected with s. neurona based on the molecular characterization of sporocysts from intestinal scrapings or feces. risk factors evaluated fo ... | 2009 | 19735983 |
| ectoparasites and associated pathogens of free-roaming and captive animals in zoos of south carolina. | a survey of ectoparasites and their associated pathogens was conducted in two south carolina zoos, from 2004 to 2007. dead, wild birds and mammals, as well as captive animals examined during routine veterinary checks constituted the study populations. ectoparasites were tested for species of anaplasma, bartonella, coxiella burnetii, ehrlichia, rickettsia, and trypanosoma. forty-six species of ectoparasites were collected from 133 free-roaming and captive hosts and their associated nesting and be ... | 2009 | 18973443 |
| discovery of an endemic area of gnathostoma turgidum infection among opossums, didelphis virginiana, in mexico. | gnathostomosis, caused by gnathostoma binucleatum, is a serious public health issue in mexico. although 2 other gnathostoma spp., g. turgidum and g. lamothei, have been found in wild animals, their natural life cycle or their relation to human disease remains unclear. while we were conducting an epidemiological survey on gnathostoma spp. in sinaloa state, mexico, we found an endemic area for g. turgidum in common opossums, didelphis virginiana, located in tecualilla, sinaloa. the species identif ... | 2009 | 18989999 |
| evaluation of the chagas stat-pak assay for detection of trypanosoma cruzi antibodies in wildlife reservoirs. | an immunochromatographic assay (chagas stat-pak) was evaluated for the detection of trypanosoma cruzi antibodies in 4 species of wildlife reservoirs. antibodies to t. cruzi were detected in raccoons (procyon lotor) (naturally and experimentally infected) and degus (octodon degu) (experimentally-infected) using the chagas stat-pak. in naturally exposed wild raccoons, the chagas stat-pak had a sensitivity and specificity of 66.7-80.0% and 96.3%, respectively. compared with indirect immunofluoresce ... | 2009 | 19016578 |
| is gnathostoma turgidum an annual parasite of opossums? drastic seasonal changes of infection in didelphis virginiana in mexico. | gnathostoma turgidum is a nematode that parasitizes the stomach of opossums, didelphis virginiana. despite its wide distribution in the americas, its natural life cycle is poorly understood. recently, we found an endemic area for g. turgidum infection in sinaloa, mexico (diaz-camacho et al., 2009). based on sporadic surveys for several years, the prevalence was apparently high in summer and extremely low in winter. to confirm that this is really a seasonal variance, we conducted a longitudinal s ... | 2009 | 19281297 |
| a novel sarcocystis-associated encephalitis and myositis in racing pigeons. | sarcosporidian cysts in the skeletal muscle of domestic pigeons (columba livia f. domestica) have previously been attributed to infection with sarcocystis falcatula, which is shed in the faeces of the opossum (didelphis virginiana). here, we describe fatal spontaneous encephalitis and myositis associated with sarcocystis infections in three flocks of racing pigeons with 47 of 244 animals affected. the clinical course was characterized by depression, mild diarrhoea, torticollis, opisthotonus, par ... | 2009 | 19322710 |
| besnoitia darlingi infection in a virginia opossum (didelphis virginiana). | this is a case report of natural infection with besnoitia darlingi in a virginia opossum (didelphis virginiana) in louisiana. clinical pathologic data included a severe nonregenerative anemia, inflammatory leukogram, increased hepatocellular leakage enzymes, renal azotemia, hyperkalemia, hypoglycemia, hypoalbuminemia, and proteinuria. tissue cysts containing bradyzoites were found in the majority of organs, especially the skin, mucous membranes, kidneys, adrenals, lungs, and heart. images of the ... | 2009 | 19368269 |
| skeletal lesions in a population of virginia opossums (didelphis virginiana) from baldwin county, georgia. | antemortem skeletal lesions were analyzed in 61 virginia opossums (didelphis virginiana) collected as roadkill from baldwin county, georgia, usa. as evidenced by bridging fracture calluses, misalignments, bone-surface depressions, perforations, localized superficial calluses, periosteal proliferations, and bony bridges across intervertebral disk spaces, 64% of the individuals had signs of one or more healed injuries. within the subset of skeletons with bone lesions, 54% had healed rib fractures ... | 2009 | 19395742 |
| seasonal source-sink dynamics at the edge of a species' range. | the roles of dispersal and population dynamics in determining species' range boundaries recently have received theoretical attention but little empirical work. here we provide data on survival, reproduction, and movement for a virginia opossum (didelphis virginiana) population at a local distributional edge in central massachusetts (usa). most juvenile females that apparently exploited anthropogenic resources survived their first winter, whereas those using adjacent natural resources died of sta ... | 2009 | 19569372 |
| genetically different isolates of trypanosoma cruzi elicit different infection dynamics in raccoons (procyon lotor) and virginia opossums (didelphis virginiana). | trypanosoma cruzi is a genetically and biologically diverse species. in the current study we determined t. cruzi infection dynamics in two common north american reservoirs, virginia opossums (didelphis virginiana) and raccoons (procyon lotor). based on previous molecular and culture data from naturally-exposed animals, we hypothesised that raccoons would have a longer patent period than opossums, and raccoons would be competent reservoirs for both genotypes t. cruzi i (tci) and tciia, while opos ... | 2009 | 19607833 |
| human bloodfeeding by the recently introduced mosquito, aedes japonicus japonicus, and public health implications. | knowledge of the host-feeding behavior and extent of interactions with human hosts are important in evaluating the role and vector potential of invasive mosquitoes in transmission of native arboviruses. we collected blood-engorged females of the recently established exotic species aedes japonicus japonicus from sites in new jersey during 2000 to 2007 and identified the sources of vertebrate blood meals by sequencing portions of the cytochrome b gene of mitochondrial dna. over 1/3 (36%, n = 36) o ... | 2009 | 19653507 |
| antibodies to west nile virus in raccoons and other wild peridomestic mammals in iowa. | surveillance for evidence of west nile virus (wnv) infection in small- and medium-sized wild mammals was conducted in iowa, usa, from may 2005 to june 2007. sera were collected from 325 mammals belonging to nine species and tested for antibodies to wnv and other flaviviruses by epitope-blocking enzyme-linked immunosorbent assay (elisa). all sera that had antibodies to flaviviruses by blocking elisa were further examined by plaque reduction neutralization test (prnt). thirteen mammals were seropo ... | 2009 | 19901390 |
| isolation of 21 polymorphic microsatellite markers for the virginia opossum (didelphis virginiana). | twenty-one polymorphic microsatellite markers were developed for the virginia opossum (didelphis virginiana). the number of alleles ranged from two to 13 and observed heterozygosities ranged from 0.464 to 0.964. significant heterozygote deficiencies were observed at three loci and null alleles were detected at five loci. evidence for gametic disequilibrium was observed between three sets of paired loci after a sequential bonferroni correction was applied. these markers will enable us to investig ... | 2009 | 21564875 |
| behavioral and nutritional aspects of the virginian opossum (didelphis virginiana). | virginia opossums are widely distributed throughout the united states, except in the most arid regions, and wild individuals are commonly brought to practitioners for medical attention. opossums' popularity as pets seems to be growing, and it is likely that pet opossums will be more common in veterinary practice. clinicians must be aware of natural opossum behaviors so that thorough physical examination and diagnostic procedures can be performed on injured patients. for animals kept captive long ... | 2009 | 19341950 |
| real-time dynamics of nitric oxide shifts within the esophageal wall. | currently, indirect evidence suggests that the neurotransmitter nitric oxide (no) plays a crucial role in the genesis of aboral propagation of esophageal peristalses during swallowing. however, direct evidence in this regard currently is lacking. this study aimed to assess the feasibility of using no-selective microprobes to detect real-time no changes within the esophageal wall of north american opossums (didelphis virginiana) during normal progressive esophageal peristalsis and induced esophag ... | 2009 | 19263142 |
| neutralization of lethality and proteolytic activities of malayan pit viper (calloselasma rhodostoma) venom with north american virginia opossum (didelphis virginiana) serum. | malayan pit viper (calloselasma rhodostoma) envenomation is a major health problem in south east asia. during envenomation, venom components mainly affect the hemostatic system. the sera from the north american virginia opossums (didelphis virginiana) were able to neutralize the venom of the malayan pit viper. these natural inhibitors could be explored as potential therapeutics against envenomations of a variety of venomous snake species in different geographical habitats. | 2008 | 18617212 |
| modest genetic differentiation among north american populations of sarcocystis neurona may reflect expansion in its geographic range. | sarcocystis neurona is an important cause of neurological disease in horses (equine protozoal myeloencephalitis, epm) and sea otters in the united states. in addition, epm-like disease has been diagnosed in several other land and marine mammals. opossums are its only definitive hosts. little genetic diversity among isolates of s. neurona from different hosts has been reported. here, we used 11 microsatellites to characterize s. neurona dna isolated from natural infections in 22 sea otters (enhyd ... | 2008 | 18243561 |
| relationships between human disturbance and wildlife land use in urban habitat fragments. | habitat remnants in urbanized areas typically conserve biodiversity and serve the recreation and urban open-space needs of human populations. nevertheless, these goals can be in conflict if human activity negatively affects wildlife. hence, when considering habitat remnants as conservation refuges it is crucial to understand how human activities and land uses affect wildlife use of those and adjacent areas. we used tracking data (animal tracks and den or bed sites) on 10 animal species and infor ... | 2008 | 18254856 |
| diversity, seasonality, and context of mammalian roadkills in the southern great plains. | thousands of mammals are killed annually from vehicle collisions, making the issue an important one for conservation biologists and environmental managers. we recorded all readily identifiable kills on or immediately adjacent to roads in the southern great plains from march 2004-march 2007. we also recorded distance traveled, whether a road was paved or divided, the number of lanes, and prevailing habitat. surveys were opportunistic and were conducted by car during conditions of good visibility. ... | 2008 | 18299918 |
| the development of a testosterone stimulation test in the virginia opossum (didelphis virginiana) and its use in evaluating deslorelin contraception. | the aims of the present study were to examine the variability of testosterone secretion in the virginia opossum over a 24 h period and to develop a testosterone stimulation test that would provide an index of the prevailing testosterone biosynthetic capacity of the testes; the latter was used to clinically evaluate the efficacy of a gonadotrophin-releasing hormone agonist contraceptive. sexually-mature captive opossums (n = 12) located in africam safari (mexico) sampled every 12 h over 24 h cons ... | 2008 | 18577353 |
| distribution of mycobacterium avium subspecies paratuberculosis in the lower florida keys. | johne's disease, a fatal and contagious gastrointestinal infection caused by mycobacterium avium subsp. paratuberculosis (map), was first diagnosed in an endangered florida key deer (odocoileus virginianus clavium) in 1996 and later in six additional key deer deaths from 1998 to 2004. we investigated the geographic distribution of map in the lower florida keys from february 2005 through may 2006 via collection of blood and fecal pellets from 51 live-captured deer, collection of 550 fecal samples ... | 2008 | 18689642 |
| detection of lawsonia intracellularis by real-time pcr in the feces of free-living animals from equine farms with documented occurrence of equine proliferative enteropathy. | the objective of this study was to determine whether lawsonia intracellularis was present in the feces of free-living animals collected on two equine premises with documented occurrence of equine proliferative enteropathy (epe). fresh feces from black-tailed jackrabbits (lepus californicus, n=100), striped skunks (mephitis mephitis, n=22), feral cats (felis catus, n=14), brewer's blackbirds (euphagus cyanocephalus, n=10), virginian opossums (didelphis virginiana, n=9), raccoons (procyon lotor, n ... | 2008 | 18957657 |
| evaluation of cruzia americana, turgida turgida, and didelphostrongylus hayesi infection in the virginia opossum (didelphis virginiana) and risk factors along the california coast. | three nematodes, turgida turgida, cruzia americana, and didelphostrongylus hayesi, have been documented to cause morbidity and mortality in the virginia opossum (didelphis virginiana). the present study was designed to determine the frequency of infection of these nematodes in opossums at 2 study sites in california and to determine if there are risk factors associated with shedding of eggs or larvae in the feces. turgida turgida and c. americana adults were found in 84.4% (stomach; n = 45) and ... | 2008 | 18973414 |
| comparison of the muscle mechanics of the forelimb of three climbers. | the climbing behavior, muscle mechanics, and functional properties of selected forelimb muscles were examined to ascertain how three distantly related mammals may be adapted for climbing. to determine if features of the fox squirrel (stalheim-smith: j. morphol. 180:55-68, '84) are general or unique features for a climber, two distantly related climbers, the raccoon (procyon lotor) and the opossum (didelphis virginiana), were studied. muscle mechanics varied: the elbow flexors of the fox squirrel ... | 2008 | 2810372 |
| experimental ureteral obstruction in the fetal opossum. i. renal functional assessment. | the north american opossum didelphis virginiana was used as a model for fetal urinary obstruction. in this animal the fetus develops on a teat in a pouch and, therefore, it is accessible to surgical intervention. unilateral ureteral obstruction was created at a mid trimester developmental equivalent in 8 pups, late ureteral obstruction was created in a similar fashion in 6 pups at a full-term equivalent and unobstruction of 9 pups was accomplished with a ureteroneocystostomy at a full-term equiv ... | 2008 | 2374241 |
| the development of rubrospinal, cerebellorubral, and corticorubral connections in the north american opossum. evidence for asynchronism. | we have employed axonal transport and degeneration techniques to study the development of major rubral connections in the north american opossum. opposums were chosen for study because they are born 12 d after conception and have a protracted postnatal development. our results suggest that: the red nucleus innervates the spinal cord early in development, well before the somatic motor-sensory cortex (cabana and martin, 1984); the red nucleus projects to the spinal cord before it receives substant ... | 2008 | 2442682 |
| genes flanking xist in mouse and human are separated on the x chromosome in american marsupials. | x inactivation, the transcriptional silencing of one of the two x chromosomes in female mammals, achieves dosage compensation of x-linked genes relative to xy males. in eutherian mammals x inactivation is regulated by the x-inactive specific transcript (xist), a cis-acting non-coding rna that triggers silencing of the chromosome from which it is transcribed. marsupial mammals also undergo x inactivation but the mechanism is relatively poorly understood. we set out to analyse the x chromosome in ... | 2007 | 17333537 |
| ultrastructure characteristics of besnoitia darlingitachyzoites brumpt, 1913 (protozoa: sarcocystidae) of the michigan strain mibd1. | tachyzoites of besnoitia darlingi brumpt, 1913 were redescribed based on new materials isolated from virginia opossums (didelphis virginiana, kerr) from michigan, u.s.a. tachyzoites of the mibd1 strain were propagated in bovine turbinate cell culture for more than two years. a comparison with previously described tachyzoites of the b. darlingi op1 strain from mississippi, usa revealed some morphological differences despite the remarkable genetic homogeneity between the two b. darlingi strains. m ... | 2007 | 18383798 |
| the unique paired retinal vascular pattern in marsupials: structural, functional and evolutionary perspectives based on observations in a range of species. | in the few marsupial species studied to date that possess a retinal vasculature, the arterial and venous segments, down to the smallest calibre capillaries, have been shown to occur in pairs. it is a pattern seen in the marsupial central nervous system (cns) but not in other tissues in this group or in any tissues in eutherian mammals. the aim of the present study was to investigate the presence of retinal vessels in a range of non-eutherian mammalian species (marsupials and monotremes) and to d ... | 2007 | 17475712 |
| observations on besnoitiosis in virginia opossum (didelphis virginiana) from michigan, usa. | besnoitia tissue cysts were found in five naturally-infected adult opossums (didelphis virginiana) from michigan. details of the microscopy, histopathology, ultra-structure, and genetic features of the cysts were studied to identify their species-specific traits. the materials were differentiated phenotypically from cysts of other besnoitia spp. by difference in size, pattern of tissue distribution, morphology of pellicle and nucleus, number of micronemes and rhoptries, amount of lipids and amyl ... | 2007 | 17580564 |
| salmonella enterica isolated from wildlife at two ohio rehabilitation centers. | between may and september 2004, fecal samples from various wildlife species admitted to two rehabilitation centers in ohio were cultured for salmonella enterica and escherichia coli o157:h7. eight of 71 (11%) samples, including specimens from three opossums (didelphis virginiana), two gray squirrels (sciurus carolinensis), a woodchuck (marmota monax), a harris hawk (parabuteo unicinctus), and a screech owl (otus asio) tested positive for salmonella serovars braenderup, senftenberg, oranienburg, ... | 2007 | 17939349 |
| serologic evidence of west nile virus exposure in north american mesopredators. | sera from 936 mammalian mesopredators (virginia opossums, gray foxes, striped skunks, hooded skunks, raccoons, a bobcat, and a red fox) were collected during 2003 and 2004 in california, arizona, texas, louisiana, ohio, and wyoming and screened for flavivirus-specific antibodies by an epitope-blocking enzyme-linked immunosorbent assay (blocking elisa). serum samples positive for antibodies against flaviviruses were screened for west nile virus (wnv)-specific antibodies by blocking elisa and sele ... | 2007 | 17255248 |
| the development of selected rubral connections in the north american opossum. | we have employed axonal transport and degeneration techniques to study the development of selected rubral connections in the north american opossum. opossums were chosen for study because they are born in an immature state, 12 days after conception, and have a lengthy postnatal development. the results of our studies suggest that: (1) the red nucleus innervates the spinal cord early in development, but not as early as some areas of the brainstem; (2) rubrospinal development occurs postnatally in ... | 2007 | 3382514 |
| the brainstem origin of monoaminergic projections to the spinal cord of the north american opossum: a study using fluorescent tracers and fluorescence histochemistry. | the retrograde transport of fluorescent markers has been combined with the glyoxylic acid and falck-hillarp techniques to identify the origin of monoamine axons within the spinal cord of the north american opossum. catecholamine axons arise from neurons located within the ventrolateral medulla, dorsal to the superior olivary complex, within the dorsolateral and rostrolateral pons and within the periventricular nuclei of the hypothalamus. such neurons are most numerous within the dorsolateral pon ... | 2007 | 6129037 |
| flea (pulex simulans) infestation in captive giant anteaters (myrmecophaga tridactyla). | a pair of captive adult giant anteaters (myrmecophaga tridactyla) presented heavily infested with a flea species (pulex simulans) commonly found on virginia opossums (didelphis virginiana) and raccoons (procyon lotor) in the central united states. in this case, the flea was demonstrated to have completed its entire life cycle with the anteaters as the host. a single treatment of topical imidacloprid, coupled with removal and replacement of infested bedding, was rapidly effective at controlling t ... | 2006 | 17319150 |
| genetic variation among isolates of sarcocystis neurona, the agent of protozoal myeloencephalitis, as revealed by amplified fragment length polymorphism markers. | sarcocystis neurona causes serious neurological disease in horses and other vertebrates in the americas. based on epidemiological data, this parasite has recently emerged. here, the genetic diversity of sarcocystis neurona was evaluated using the amplified fragment length polymorphism (aflp) method. fifteen s. neurona taxa from different regions collected over the last 10 years were used; six isolates were from clinically diseased horses, eight isolates were from wild-caught opossums (didelphis ... | 2006 | 16714575 |
| endemic infections of parastrongylus (=angiostrongylus) costaricensis in two species of nonhuman primates, raccoons, and an opossum from miami, florida. | parastrongylus (=angiostrongylus) costaricensis was first reported in the united states from cotton rats, sigmodon hispidus, in texas in 1979. here, we report the findings of p. costaricensis in a siamang (hylobates syndactylus) from the miami metrozoo, in 2 ma's night monkeys (aotus nancymaae) from the dumond conservancy located at monkey jungle in miami, in 4 raccoons (procyon lotor) trapped near the metrozoo, and in an opossum (didelphis virginiana) trapped at the metrozoo. these records are ... | 2006 | 16729706 |
| common procedures in hedgehogs, prairie dogs, exotic rodents, and companion marsupials. | nondomesticated species are commonly being kept as companion animals. these include the african pygmy hedgehog (atelerix albi-ventris), the north american black-tailed prairie dog (cynomys lu-dovicianus), and exotic rodents such as the degu (octodon degus)and duprasi or fat-tailed gerbil (pachyuromys duprasi). common companion marsupials include the sugar glider (petaurus breviceps),bennett's or tammar (dama) wallabies (macropus rufogriseus rufo-griseus and macropus eugenii, respectively), the b ... | 2006 | 16759954 |
| prevalence of agglutinating antibodies to toxoplasma gondii in striped skunks (mephitis mephitis), opossums (didelphis virginiana), and raccoons (procyon lotor) from connecticut. | the prevalence of agglutinating antibodies to toxoplasma gondii was examined in striped skunks (mephitis mephitis), opossums (didelphis virginiana), and raccoons (procyon lotor) from 8 cities in connecticut. ten (42%) of the 24 striped skunks, 2 of 7 (29%) opossums, and 12 of 12 (100%) raccoons were positive at dilutions of 1:50 or greater. these results suggest that t. gondii is prevalent in the environment, or prey items, or both, of these omnivores in connecticut. | 2006 | 16884022 |
| imprinting of opossum igf2r in the absence of differential methylation and air. | phylogenetic comparison of extant mammals with divergent imprint status is a powerful method for identifying critical components of imprint regulation at individual loci. the entire genomic region of igf2r in the imprinted marsupials, didelphis virginiana and monodelphis domestica, and the non-imprinted monotreme, ornithorhynchus anatinus, was isolated and sequenced. genetic and epigenetic comparisons of over 160 kb of sequence were then performed in five distinct mammalian species. surprisingly ... | 2006 | 17998818 |
| lack of sarcocystis neurona antibody response in virginia opossums (didelphis virginiana) fed sarcocystis neurona-infected muscle tissue. | serum was collected from laboratory-reared virginia opossums (didelphis virginiana) to determine whether experimentally infected opossums shedding sarcocystis neurona sporocysts develop serum antibodies to s. neurona merozoite antigens. three opossums were fed muscles from nine-banded armadillos (dasypus novemcinctus), and 5 were fed muscles from striped skunks (mephitis mephitis). serum was also collected from 26 automobile-killed opossums to determine whether antibodies to s. neurona were pres ... | 2006 | 16884017 |
| efferent connections of the caudate nucleus in the virginia opossum. | the efferents of the opossum's caudate nucleus were investigated by charting the the fiber degenerations produced by electrolytic lesions in various parts of this nucleus. by the aid of a modified fink-heimer procedure, degenerating fibers were traced from each of the lesions to the small globus pallidus in which they appeared to be distributed in an orderly dorsoventral pattern. fibers from all lesion sites in the caudate nucleus were found to terminate in the entopedunucular nucleus. in the su ... | 2005 | 1262560 |
| studies on the energy metabolism of opossum (didelphis virginiana) erythrocytes--vi. de novo purine nucleotide biosynthesis is limited to the final steps of the pathway in vitro. | 1. high pressure liquid radiochromatography was used to show the incorporation of [14c] formate with z-compounds into atp and gtp in opossum erythrocytes. 2. the use of z-riboside with [14c] formate resulted in more extensive labeling of atp than the z-base/[14c] formate combination as substrates for nucleotide biosynthesis. 3. substantial accumulation of zmp and ztp, but no zdp was detected in the chromatograms. 4. atp was unstable in red cells metabolizing in the presence of z-compounds under ... | 2005 | 2253476 |
| the role of feral mammals on wildlife infectious disease prevalence in two nature reserves within mexico city limits. | wild and feral medium-sized mammals were live trapped at two natural protected areas within the mexico city limits to determine antibody prevalence for the most common infectious diseases (rabies, toxoplasmosis, and canine parvovirus) in dogs and cats. mammals were trapped during the dry (march-april) and rainy seasons (july-august) of 1996 and 1997. a total of 68 individuals were captured, representing 8 species: opossums (didelphis virginiana), ringtails (bassariscus astutus), spotted skunks ( ... | 2005 | 17312768 |
| large mesozoic mammals fed on young dinosaurs. | mesozoic mammals are commonly portrayed as shrew- or rat-sized animals that were mainly insectivorous, probably nocturnal and lived in the shadow of dinosaurs. the largest known mesozoic mammal represented by substantially complete remains is repenomamus robustus, a triconodont mammal from the lower cretaceous of liaoning, china. an adult individual of r. robustus was the size of a virginia opossum. here we report a new species of the genus, represented by a skeleton with most of the skull and p ... | 2005 | 15650737 |
| comparative sequencing provides insights about the structure and conservation of marsupial and monotreme genomes. | sequencing and comparative analyses of genomes from multiple vertebrates are providing insights about the genetic basis for biological diversity. to date, these efforts largely have focused on eutherian mammals, chicken, and fish. in this article, we describe the generation and study of genomic sequences from noneutherian mammals, a group of species occupying unusual phylogenetic positions. a large sequence data set (totaling >5 mb) was generated for the same orthologous region in three marsupia ... | 2005 | 15718282 |
| dexamethasone treatment induces susceptibility of outbred webster mice to experimental infection with besnoitia darlingi isolated from opossums (didelphis virginiana). | the sarcocystidae comprise a diverse, monophyletic apicomplexan parasite family, most of whose members form intracellular cysts in their intermediate hosts. the extent of pathology associated with such cyst formation can range widely. we currently lack experimental animal models for many of these infections. here we explored dexamethasone treatment as a means to render outbred mice susceptible to besnoitia darlingi infection and demonstrated that this approach allows viable parasites to be subse ... | 2005 | 15759157 |
| helminths of the virginia opossum didelphis virginiana (mammalia: didelphidae) in mexico. | the goal of this study was to provide further information about helminth parasites of virginia opossum didelphis virginiana kerr, 1792 from mexico. during routine faunal investigations between 1958 and 2001, 101 opossum were necropsied. nineteen taxa of helminths were collected, representing 13 genera from hosts in 27 localities from mexico. there are 58 new locality records, with 6 species recorded in mexico for the first time: brachylaima virginiana dickerson, 1930; cruzia americana mapleston, ... | 2005 | 15856909 |
| serologic evidence of exposure of wild mammals to flaviviruses in the central and eastern united states. | serosurveys were conducted to obtain flavivirus and west nile virus (wnv) seroprevalence data from mammals. sera from 513 small- and medium-sized mammals collected during late summer and fall 2003 from colorado, louisiana, new york, ohio, and pennsylvania were screened for flavivirus-specific antibodies. sera samples containing antibody to flaviviruses were screened for wnv-specific antibodies by epitope-blocking enzyme-linked immunosorbent assays and confirmed with plaque reduction neutralizati ... | 2005 | 15891139 |
| serologic evidence of west nile virus infection in free-ranging mammals, slidell, louisiana, 2002. | after an outbreak of west nile virus (wnv) infections in slidell, louisiana, in 2002, we detected neutralizing antibodies to wnv in 13 of 120 mammals, representing five of six species sampled. seroprevalence was measured in opossum, didelphis virginiana (75%, n = 8), raccoons, procyon lotor (60%, n = 5), black rats, rattus rattus (6%, n = 36), hispid cotton rats, sigmodon hispidus (4%, n = 24), and eastern gray squirrels, sciurus carolinensis (2%, n = 43). | 2005 | 16187899 |
| isolation of mycobacterium avium subsp paratuberculosis (map) from feral cats on a dairy farm with map-infected cattle. | paratuberculosis is an economically important disease of dairy cattle caused by mycobacterium avium subsp. paratuberculosis (map). the role of nonruminant, nondomestic animals in the epidemiology of paratuberculosis in cattle is unclear. to examine nonruminant, nondomestic animals for the presence of map, 25 feral cats, nine mice (species unknown), eight rabbits (sylvilagus floridanus), six raccoons (procyon lotor), and three opossums (didelphis virginiana) were collected from a mid-western dair ... | 2005 | 16244077 |
| bartonella and rickettsia in fleas and lice from mammals in south carolina, u.s.a. | species in the genera bartonella and rickettsia are vector-borne pathogens of humans and domestic animals. the natural reservoirs and enzootic transmission cycles of these bacteria are poorly known in south carolina. thirteen species of lice and fleas were collected from urban animals and screened for the presence of bartonella and rickettsia by pcr amplification using genus-specific primers. bartonella henselae was present in cat fleas (ctenocephalides felis) from virginia opossums (didelphis v ... | 2005 | 16599169 |
| experimental talipes in the virginia opossum. | 2005 | 5133035 | |
| immunohistochemical localization of gastrin-releasing peptide, neuronal nitric oxide synthase and neurone-specific enolase in the uterus of the north american opossum, didelphis virginiana. | the present study has demonstrated the immunohistochemical localization of gastrin-releasing peptide (grp), neuronal nitric oxide synthase (nnos) and neurone-specific enolase (nse) in the uterus of the north american opossum. although the presence of grp, nnos and nse has been reported recently in the uterus of eutherian species this is the first description of these peptides in a metatherian species. metatherian mammals are of interest because in these species it is the prolonged lactation phas ... | 2005 | 15996123 |
| concurrent presence of sarcocystis neurona sporocysts, besnoitia darlingi tissue cysts, and sarcocystis inghami sarcocysts in naturally infected opossums (didelphis virginiana). | opossums (didelphis virginiana) are exposed to a wide range of coccidia through feeding on a variety of foods, including, but not limited to, carrion, insects, and nestling birds. abundant d. virginiana populations in urban and suburban areas can be important reservoirs of parasitic infection because of their profuse and prolonged excretion of the sporocysts of several species of sarcocystis, their omnivorous diet, and their relatively long life span. this report describes 2 adult female opossum ... | 2004 | 15305752 |
| phylogenetic footprint analysis of igf2 in extant mammals. | genomic imprinting results in monoallelic gene transcription that is directed by cis-acting regulatory elements epigenetically marked in a parent-of-origin-dependent manner. we performed phylogenetic sequence and epigenetic comparisons of igf2 between the nonimprinted platypus (ornithorhynchus anatinus) and imprinted opossum (didelphis virginiana), mouse (mus musculus), and human (homo sapiens) to determine if their divergent imprint status would reflect differences in the conservation of genomi ... | 2004 | 15342558 |
| molecular characterization and evolution of x and y-borne atrx homologues in american marsupials. | in eutherians, the sex-reversing atrx gene on the x has no homologue on the y chromosome. however, testis-specific and ubiquitously expressed x-borne genes have been identified in australian marsupials. we studied nucleotide sequence and chromosomal location of atrx homologues in two american marsupials, the opossums didelphis virginiana and monodelphis domestica. a pcr fragment of m. domestica atrx was used to probe southern blots and to screen male genomic libraries. southern analysis demonstr ... | 2004 | 15702418 |
| prevalence of and risk factors associated with the presence of sarcocystis neurona sporocysts in opossum (didelphis virginiana) from michigan: a retrospective study. | from april 1996 to december 2002 the prevalence of sarcocystis neurona sporocysts in north american opossum (didelphis virginiana) in southern michigan was estimated. sporocysts of s. neurona were found in intestinal scrapings from 31 (15%) of 206 examined opossum. the frequency of infection was higher in adult animals (26/206; 12.6%) and females (19/206; 9.2%) than in juveniles (5/206; 2.4%) and males (12/206; 5.8%). also, prevalence of s. neurona sporocysts in opossums in relation to factors s ... | 2004 | 15482884 |
| viability of sarcocystis neurona sporocysts after long-term storage. | the effect of long-term storage on the viability and infectivity of sarcocystis neurona sporocysts was investigated. s. neurona sporocysts were harvested from the small intestine of virginia opossums from 1996 to 2002 and stored at 4 degrees c. viability of sporocysts was assessed by propidium iodide (pi) exclusion assay, in vitro excystation and development in tissue cultures, and bioassay in gamma-interferon gene knockout (gamma-ifn-ko) mice. the rate of excystation was apparently unaffected b ... | 2004 | 15325051 |
| prevalence of sarcocystis species sporocysts in northern virginia opossums (didelphis virginiana). | a total of 206 virginia opossums ( didelphis virginiana) collected from the mid-michigan region, united states, during a period extending from 1996 to 2002 were sampled for the presence of sarcocystis spp sporocysts. all isolates were phenotypically identified as sarcocystis spp and genotyped to the species level by pcr-based techniques. the overall prevalence of sarcocystis spp in opossums was 18% (37/206). the prevalence of sarcocystis spp differed significantly with age ( p<0.001) and adult o ... | 2004 | 15205944 |
| electrical stimulation of the vagus nerve restores motility in an animal model of achalasia. | esophageal peristalsis generally does not return to normal after surgical treatment of achalasia. direct electrical stimulation of the vagus nerve is known to stimulate antegrade peristalsis in the normal esophagus; however, it is not known whether electrical stimulation will induce return of peristalsis once an achalasia-like disorder has been established. the objective of this study was to perform quantitive and qualitative measurements of motility during electrical stimulation of the vagal ne ... | 2003 | 14592656 |
| sarcocystis inghami n. sp. (sporozoa: sarcocystidae) from the skeletal muscles of the virginia opossum didelphis virginiana in michigan. | this report describes the newly identified sarcocystis inghami n. sp. from the skeletal muscles of opossums (mammalia: didelphidae) that were collected from south central michigan (42 degrees 43'-42 degrees 79'n, 84 degrees 18'-84 degrees 86'w), usa. the new species is distinguished from all species described from north and south american opossums by the distinctive morphology of the villar protrusions on the cyst wall. sarcocysts of s. inghami are microscopic, up to 700 microm long and 110 micr ... | 2003 | 12975625 |
| carpal ontogeny in monodelphis domestica and caluromys philander (marsupialia). | carpal bones have experienced numerous changes during marsupial evolution, even though their diversity and development remain poorly studied. the aim of this work was to document adult form and the pattern of mesenchymal tissue condensation and formation of chondrification and ossification centers in the hand of two marsupials. two fundamental questions were asked: whether the loss of embryonic precursors was associated with the loss of adult elements, or whether there were developmental signs o ... | 2003 | 16351892 |
| purification of sarcocystis neurona sporocysts from opossum (didelphis virginiana) using potassium bromide discontinuous density gradient centrifugation. | this report describes a new, inexpensive procedure for the rapid and efficient purification of sarcocystis neurona sporocysts from opossum small intestine. s. neurona sporocysts were purified using a discontinuous potassium bromide density gradient. the procedure provides a source of sporocyst wall and sporozoites required for reliable biochemical characterization and for immunological studies directed at characterizing antigens responsible for immunological responses by the host. the examined i ... | 2003 | 12756543 |
| host associations and seasonal occurrence of haemaphysalis leporispalustris, ixodes brunneus, i. cookei, i. dentatus, and i. texanus (acari: ixodidae) in southeastern missouri. | hemaphysalis leporispalustris (packard), ixodes brunneus koch, ixodes cookei packard, ixodes dentatus marx, and ixodes texanus banks were collected during a 3-yr study of pathogen-tick-host interactions in southeastern missouri. h. leporispalustris was collected from the eastern cottontail rabbit, northern bobwhite, and carolina wren, and it was active all year. i. brunneus was collected by drag and from passerine birds during december, march, and april. i. cookei was collected from raccoons and ... | 2003 | 12597662 |
| besnoitia oryctofelisi n. sp. (protozoa: apicomplexa) from domestic rabbits. | a species of besnoitia from naturally infected rabbits from argentina was propagated experimentally in mice, gerbils, rabbits, cats, and cell cultures. cats fed tissue cysts from rabbits shed oocysts with a prepatent period of nine to 13 days. sporulated oocysts were infective to gerbils, rabbits, outbred swiss webster and interferon gamma gene knockout mice. bradyzoites were infective orally to gerbils and cats. tachyzoites were successfully cultivated and maintained in vitro in bovine monocyte ... | 2003 | 12879849 |
| experimental aerosol inoculation of mycobacterium bovis in north american opossums (didelphis virginiana). | the goal of this study was to evaluate the susceptibility of north american opossums (didelphis virginiana) to aerosol inoculation of mycobacterium bovis at two dose levels in order to gain information on disease pathogenesis, fecal shedding of the organism, and the potential role that opossums play in the spread of this disease in nature. six opossums received high dose (1 x 10(7) colony forming units (cfu) by aerosol inoculation, six opossums received low dose (1 x 10(3) cfu inoculation, and s ... | 2003 | 12910771 |
| prevalence and tissue distribution of besnoitia darlingi cysts in the virginia opossum (didelphis virginiana) in michigan. | specimens of virginia opossums (didelphis virginiana) in michigan were examined over 1 year to document the presence of besnoitia darlingi cysts. cyst morphology, prevalence, seasonal variation, and tissue sites of isolation were studied. histology and ultrastructural features of the detected cysts and bradyzoites were consistent with b. darlingi. in the opossums, b. darlingi had intracellular tissue cysts. tissue cysts had a mean diameter of 560 microm and were separated from the host tissue by ... | 2003 | 12944045 |
| prevalence of antibodies to neospora caninum, sarcocystis neurona, and toxoplasma gondii in wild horses from central wyoming. | sarcocystis neurona, neospora caninum, n. hughesi, and toxoplasma gondii are 4 related coccidians considered to be associated with encephalomyelitis in horses. the source of infection for n. hughesi is unknown, whereas opossums, dogs, and cats are the definitive hosts for s. neurona, n. caninum, and t. gondii, respectively. seroprevalence of these coccidians in 276 wild horses from central wyoming outside the known range of the opossum (didelphis virginiana) was determined. antibodies to t. gond ... | 2003 | 14533680 |
| a serosurvey of leptospirosis in connecticut peridomestic wildlife. | recently, leptospirosis has gained attention as a re-emerging infection in domestic dogs in the northeastern united states. in order to gain insight into the epizootiology of leptospirosis in this region, 109 small wild mammals (31 raccoons (procyon lotor), 30 skunks (mephitis mephitis), 28 opossums (didelphis virginiana), and 20 gray squirrels (sciurus carolinensis)) collected between february 27 and september 17, 2001 were tested for serologic evidence of exposure to five common leptospira ser ... | 2003 | 14733671 |
| neurologic disease in gamma-interferon gene knockout mice caused by sarcocystis neurona sporocysts collected from opossums fed armadillo muscle. | fifteen gamma-interferon gene knockout mice were each orally inoculated with 5 x 10(3) sarcocystis sporocysts derived from virginia opossums (didelphis virginiana) fed nine-banded armadillo (dasypus novemcinctus) muscle containing sarcocysts. three mice were inoculated with similarly obtained homogenates, but in which no sporocysts were detected. mouse m8 was pregnant when inoculated and gave birth during the trial. fifteen of 15 (100%) mice inoculated with sporocysts developed neurologic signs ... | 2002 | 11751001 |
| sarcocystis neurona reacting antibodies in missouri feral domestic cats (felis domesticus) and their role as an intermediate host. | sarcocystis neurona is the parasite associated with equine protozoal myeloencephalitis (epm). recently, cats (felis domesticus) have been implicated as a potential intermediate host in the life cycle of s. neurona. this study was initiated to determine whether cats have antibodies that react to s. neurona antigens similar to antibodies from horses with epm, and to evaluate the role of cats as intermediate hosts in the parasite's life cycle. nine feral cats were used for analysis. only one had an ... | 2002 | 11826870 |
| seroprevalence of trypanosoma cruzi in raccoons from south carolina and georgia. | trypanosoma cruzi, the causative agent of american trypanosomiasis or chagas' disease, is of both medical and veterinary importance as is evidenced by chronic phase myocarditis in humans and dogs. further, t. cruzi has been reported from over 20 species of wildlife reservoir hosts in the usa, with raccoons (procyon lotor) and opossums (didelphis virginiana) being the most common. whereas previous studies on t. cruzi in raccoons have included only culture and direct examination of blood, the indi ... | 2002 | 11838232 |