hantavirus (bunyaviridae) infections in rodents from orange and san diego counties, california.during a screening program to determine the extent of hantavirus activity in orange and san diego counties, california, serum samples from 2,365 rodents representing nine genera and 15 species were tested for hantavirus antibodies. a reverse transcription-polymerase chain reaction on selected seropositive rodents was used to identify the specific hantavirus. rodents positive for sin nombre virus (snv) antibodies by western blot included 86 (9.1%) of 948 deer mice (peromyscus maniculatus), four ( ...19999988327
do unusual site-specific population dynamics of rodent reservoirs provide clues to the natural history of hantaviruses?between january 1995 and november 1997, longitudinal mark-recapture studies of rodent hosts of hantaviruses in a disturbed microhabitat within a shortgrass prairie ecosystem in southeastern colorado (usa) were conducted. the site was distinguished by edaphic and floristic characteristics unique to this area and associated with historical land use patterns, as well as the year-around availability of water from a functioning windmill. populations of two common rodent species that are hosts for han ...200111310878
pneumocystosis in wild small mammals from california.cyst forms of the opportunistic fungal parasite pneumocystis carinii were found in the lungs of 34% of the desert shrew, notiosorex crawfordi (n = 59), 13% of the ornate shrew, sorex ornatus (n = 55), 6% of the dusky-footed wood rat, neotoma fuscipes (n = 16), 2.5% of the california meadow vole, microtus californicus (n = 40), and 50% of the california pocket mouse, chaetodipus californicus (n = 2) caught from southern california between february 1998 and february 2000. cysts were not found in a ...200111310900
ectoparasite diversity and exposure to vector-borne disease agents in wild rodents in central coastal california.a survey of wild rodents was performed in the morro bay area of central coastal california to determine serological and polymerase chain reaction (pcr) prevalence of anaplasma phagocytophilum dumler, barbet, bekker, dasch, palmer, ray, rikihisa, and rurangirwa, borrelia burgdorferi johnson, schmidt, hyde, steigerwalt, and brenner, francisella tularensis mccoy, and yersinia pestis yersin; to describe the ectoparasitic fauna on important vector-borne disease hosts; and to determine whether pathoge ...200717427705
supernumerary chromosomes of the harvest mouse, reithrodontomys megalotis. 19695820706
hydrocephalus in the western harvest mouse. 19676055323
detection and characterization of borrelia bissettii in rodents from the central california coast.this is the first report of borrelia burgdorferi sensu lato in rodents from san luis obispo county, with most isolates obtained from a previously unreported host, neotoma lepida thomas. b. burgdorferi sensu lato was identified in seven rodent species, including the california vole, microtus californicus peale; dusky-footed woodrat, neotoma fuscipes baird; desert woodrat, neotoma lepida thomas; brush mouse, peromyscus boylii baird; california mouse, peromyscus californicus gambel; deer mouse, per ...200415311469
role of small mammals in the ecology of borrelia burgdorferi in a peri-urban park in north coastal california.the role of small mammals other than woodrats in the enzootiology of the lyme disease spirochete, borrelia burgorferi, was assessed in the peri-urban park. mammals were collected monthly from september through to april. following tick removal, the animals were tested for b. burgdorferi by culture of ear-punch biopsies. larvae and nymphs that were intermediate in morphology between ixodes spinipalpis and ixodes neotomae occurred on several species of rodents (peromyscus truei, peromyscus californ ...19979291589
an ixodes minor and borrelia carolinensis enzootic cycle involving a critically endangered mojave desert rodent.microtus californicus scirpensis is an endangered, isolated subspecies of california vole. it requires water pools and riparian bulrush (schoenoplectus americanus) and occupies some of the rarest habitat of any north american mammal. the minimally vegetated, extremely arid desert surrounding the pools is essentially uninhabitable for ixodes species ticks. we describe an enzootic cycle of borrelia carolinensis in ixodes minor ticks at a site 3500 km distant from the region in which i. minor is kn ...201425035799
effect of an invasive plant and moonlight on rodent foraging behavior in a coastal dune ecosystem.understanding how invasive plants may alter predator avoidance behaviors is important for granivorous rodents because their foraging can trigger ripple effects in trophic webs. previous research has shown that european beach grass ammophila arenaria, an invasive species in coastal california, affects the predation of other seeds by the rodents microtus californicus, peromyscus maniculatus, and reithrodontomys megalotis. this may be due to lower perceived predation risk by rodents foraging in clo ...201525679785
detection and ecology of leptospirosis in iowa gain additional information on the extent of leptospirosis in wildlife following a human outbreak in iowa, wild mammals and lower forms of life were collected. isolation, darkfield microscopic, serologic and pathologic procedures were used to identify past or present evidence of leptospiral infection. leptospires were isolated from 7 of 75 (9%) mammals. serotype grippotyphosa was isolated from three raccoons (procyon lotor) and one western harvest mouse (reithrodontomys megalotis). serotype b ...197016512128
population dynamics of a diverse rodent assemblage in mixed grass-shrub habitat, southeastern colorado, 1995-2000.we followed seasonal and year-to-year population dynamics for a diverse rodent assemblage in a short-grass prairie ecosystem in southeastern colorado (usa) for 6 yr. we captured 2,798 individual rodents (range, one to 812 individuals per species) belonging to 19 species. the two most common species, deer mice (peromyscus maniculatus) and western harvest mice (reithrodontomys megalotis), generally had population peaks in winter and nadirs in summer; several other murid species demonstrated autumn ...200515827207
epizootiology of sin nombre and el moro canyon hantaviruses, southeastern colorado, 1995-2000.sin nombre virus (snv) is an etiologic agent of hantavirus pulmonary syndrome. to better understand the natural history of this virus we studied population dynamics and temporal pattern of infection of its rodent hosts in southeastern colorado (usa) from 1995 to 2000. we present evidence for the presence of two hantaviruses, snv in deer mice (peromyscus maniculatus) and el moro canyon virus in western harvest mice (reithrodontomys megalotis), at our study sites. sin nombre virus appeared only sp ...200515827206
surveillance for borrelia burgdorferi in ixodes ticks and small rodents in british determine the prevalence of borrelia burgdorferi in british columbian ticks, fieldwork was conducted over a 2-year period. in all, 893 ticks (ixodes pacificus, i. angustus, i. soricis, ixodes spp., and dermacentor andersoni) of different life stages were retrieved from 483 small rodents (peromyscus maniculatus, perognathus parvus, and reithrodontomys megalotis). b. burgdorferi dna was detected in 5 out of 359 tick pools, and 41 out of 483 mice were serologically confirmed to have antibodies a ...201526502354
genetic identification and characterization of limestone canyon virus, a unique peromyscus-borne hantavirus.hantaviruses, family bunyaviridae, are rodent-borne rna viruses that can cause hantavirus pulmonary syndrome (hps) in various regions of the americas. a coevolutionary relationship exists between hantaviruses and their specific rodent reservoir hosts; the phylogeny of the viruses generally matches that of the rodents. there are several peromyscus-borne hantaviruses, including sin nombre virus, the most common cause of hps in north america. this report describes the genetic detection and characte ...200111485402
arenavirus antibody in rodents indigenous to coastal southern california.the purpose of this study was to extend our knowledge on the geographic and natural rodent host ranges of new world arenaviruses in california. sera from 1,094 sigmodontine and 112 murine rodents were tested for antibody against whitewater arroyo and amapari viruses. antibody was found in 55 (4.6%) of the 1,206 rodents: 4 from northwestern san diego county, 3 from los angeles county, and 48 from orange county. the antibody-positive rodents included 8 (7.8%) of 103 neotoma fuscipes, 1 (0.6%) of 1 ...200011289675
small mammals collected from a site with elevated selenium concentrations and three reference sites.small mammals were trapped in july, august, and september 1999 at kesterson reservoir (merced county, ca), a site with elevated concentrations of selenium (se), and at three nearby reference sites. deer mice (peromyscus maniculatus) were the most frequently trapped species at all of the sites, and western harvest mice (reithrodontomys megalotis) and house mice (mus musculus) were also trapped frequently. about half the animals collected from the reference sites were in reproductive condition, co ...200919373506
a survey of hantavirus antibody in small-mammal populations in selected united states national parks.hantavirus activity in 39 national parks in the eastern and central united states was surveyed by testing 1,815 small mammals of 38 species for antibody reactive to sin nombre virus. antibody-positive rodents were found throughout the area sampled, and in most biotic communities. antibody was detected in 7% of 647 deer mice (peromyscus maniculatus), 2% of 590 white-footed mice (p. leucopus), 17% of 12 rice rats (oryzomys palustris), 3% of 31 cotton rats (sigmodon hispidus), and 33% of 18 western ...19989574803
cross-transmission studies with eimeria arizonensis, e. arizonensis-like oocysts and eimeria langebarteli: host specificity at the genus and species level within the muridae.cross-transmission experiments were done using sporulated oocysts of eimeria arizonensis from peromyscus truei and peromyscus maniculatus, and oocysts of 2 putative species that resemble e. arizonensis, i.e., eimeria albigulae from neotoma albigula, and eimeria onychomysis from onychomys leucogaster. oocysts of each species were inoculated into representatives of p. maniculatus and the latter 2 rodent species. other experiments were conducted wherein oocysts of eimeria langebarteli from peromysc ...199910577723
ectoparasites of microtus californicus and possible emergence of an exotic ixodes species tick in california.california voles (microtus californicus peale) harbor fleas and ticks, may be infected with vector-borne pathogens, and could themselves suffer from disease and serve as a source of infection for people and other animals. here we summarize publications, museum archives, and recent records of ticks and fleas from california voles. there have been 18 flea species reported on california voles with geographic locations reported for 13. during recent statewide surveys, we found six flea species, with ...201526336217
small mammal survival and trapability in mark-recapture monitoring programs for hantavirus.following the 1993 hantavirus pulmonary syndrome (hps) epidemic in the south-western united states, mammalogists and epidemiologists instituted long-term studies to monitor population density and prevalence of infection in rodents which constitute the reservoir for sin nombre virus (snv). in this study, field techniques used in sampling small mammals for snv infection were evaluated to determine if trapping and handling protocols were having significant effects on future trapability or mortality ...19989476220
cocirculation of multiple hantaviruses in texas, with characterization of the small (s) genome of a previously undescribed virus of cotton rats (sigmodon hispidus).an environmental and laboratory investigation was conducted after a fatal childhood case of hantavirus pulmonary syndrome occurred in deaf smith county, texas in may 1995. a trapping campaign was conducted to identify possible rodent carriers. six species of murid and heteromyid rodents were collected, and at least one hantavirus-seropositive specimen was found in each of the five murid species. tissues from a selection of 11 seropositive specimens were examined by the polymerase chain reaction ...19969025697
nature of b chromosomes in the harvest mouse reithrodontomys megalotis by fluorescence in situ hybridization (fish).using fluorescence in situ hybridization, we examined the characteristics of two types of b chromosomes in harvest mice of the genus reithrodontomys. b chromosomes were interrogated with rdna, telomeric repeat, line element and centromeric heterochromatin probes. the two types of b chromosomes share the following features: (a) telomeres present on the ends of both arms; (b) hybridization to line probes; (c) absence of hybridization to the ribosomal gene probes; (d) c-band-positive centromeric re ...19979421265
the role of succulent halophytes in the water balance of salt marsh rodents.the role of succulent halophytes in the water balance and ecology of salt marsh rodents is dependent upon an evaluation of the composition of the available sources and the physiological properties of their potential consumers. studies of the osmotic properties of succulent halophytes from southern california coastal salt marshes are presented, together with experiments regarding the utilization of common pickleweed (salicornia virginica l.) by indigenous populations of cricetid rodents (harvest ...197028309833
prevalence and geographic genetic variation of hantaviruses of new world harvest mice (reithrodontomys): identification of a divergent genotype from a costa rican reithrodontomys mexicanus.we recently described a novel hantavirus (hmv-1) of the western harvest mouse reithrodontomys megalotis. screening of 181 additional specimens of reithrodontomys from the united states and mexico, including samples of r. mexicanus, r. sumichrasti, and r. gracilis of costa rica, for antibodies to hantavirus nucleocapsid protein revealed a widespread enzootic of hantavirus infection. genetic analyses of 7 s genomes of reithrodontomys-associated hantaviruses demonstrated that the enzootic of hmv-1 ...19957886948
occurrence of hantavirus within the rodent population of northeastern california and nevada.these studies were initiated to determine the prevalence and hosts of hantaviruses within the rodent population of nevada and northeastern california. a total of 1,867 rodents were collected, sexed, weighed, identified, and tested by enzyme-linked immunosorbent assay for the presence of antibody against hantavirus nucleocapsid. the primary hosts for hantaviruses in this region were found within the family muridae (peromyscus maniculatus. reithrodontomys megalotis. and microtus montanus). studies ...19968619434
coexistence of several novel hantaviruses in rodents indigenous to north america.three genetically distinct members of the hantavirus genus have been detected in nevada rodents by rt-pcr and nucleotide sequence analysis. these include sin nombre (sn), el moro canyon (elmc), and prospect hill (ph)-like viruses which are primarily associated with peromyscus maniculatus (deer mouse), reithrodontomys megalotis (western harvest mouse), and microtus spp. (voles), respectively. although this region of the united states is ecologically diverse, rodents infected with different hantav ...19957483255
tick paralysis in a western harvest engorging female ixodes pacificus was observed on a western harvest mouse (reithrodontomys megalotis) in humboldt county, california. the mouse demonstrated a flaccid paraplegia, but it appeared to recover fully after the tick was removed.19807431519
genetic diversity of hantaviruses in mexico: identification of three novel hantaviruses from neotominae rodents.a variety of hantaviruses are harbored by rodents in north and south america, some of which can cause hantavirus pulmonary syndrome. to obtain greater evolutionary insight into hantaviruses in the americas, a total of 211 rodents were captured in the mexican states of guerrero and morelos in 2006. anti-hantavirus antibodies were detected in 27 of 211 serum samples (12.8%) by elisa. the distribution of seropositive rodents was: 17 peromyscus beatae, 1 megadontomys thomasi, 1 neotoma picta, 6 reit ...201122138671
ticks (acari: ixodidae) collected from small and medium-sized kansas species of hard-bodied ticks were collected from 20 species of small and medium-sized mammals in kansas; amblyomma americanum l., dermacentor variabilis (say), haemaphysalis leporispalustris (packard), ixodes cookei packard, i. kingi bishopp, i. sculptus neumann, and i. texanus banks. dermacentor variabilis was found statewide, a. americanum only in the eastern one-third of the state, and the ixodes spp. and h. leporispalustris were widely scattered. the most common tick found was d. varia ...19948057327
ribosomal dna variation within and between species of rodents, with emphasis on the genus onychomys.patterns of restriction-endonuclease site and length variation at the nuclear rdna locus (18s + 28s rrna gene complex) were examined in rodents. of the 164 restriction sites mapped for seven species, 22 were conserved (mapping to the 18s, 28s, and 5.8s genes and its1) in all three onychomys species as well as in mus musculus and in three closely related peromyscine rodents, peromyscus boylii, p. eremicus, and reithrodontomys megalotis. the nontranscribed spacer (nts) region revealed most of the ...19912002766
genetic identification of a novel hantavirus of the harvest mouse reithrodontomys megalotis.we have cloned the s genomic segment of a novel hantavirus of the harvest mouse reithrodontomys megalotis. the virus is phylogenetically distinct from other hantaviruses. the new hantavirus was identified in harvest mice separated by approximately 1,000 km. a wood rat (neotoma mexicana) was found to be infected with the harvest mouse hantavirus.19948084007
nucleotide sequence analysis of the m genomic segment of el moro canyon hantavirus: antigenic distinction from four corners hantavirus.el moro canyon hantavirus (elmc, previously known as hmv-1) is associated with the western harvest mouse reithrodontomys megalotis. the interpretation that elmc is a novel hantavirus was based upon comparisons of the nucleotide sequence of the s genomic segment with those of other hantaviruses. we now show that the elmc m genome, like the s genome, is genetically similar to but distinct from that of four corners hantavirus (fc). the elmc m genome is 3801 nt in length and encodes a glycoprotein p ...19957544047
urinary proteins in four rodent species.1. mean urinary protein concentration levels are significantly higher in male peromyscus leucopus than females (98.4 and 72.4 mg/dl). 2. only females showed a significant correlation between weight and urinary protein concentration (r = 0.75 vs r = 0.03). 3. in intraspecific sexual electrophoretic comparisons of p. leucopus and p. maniculatus non-denatured urinary protein, four and two common bands were identified, respectively. males of both species showed an extra protein band. 4. four common ...19921499268
homing in the western harvest mouse, reithrodontomys megalotis. 19665905561
ecology of hantaviruses in mexico: genetic identification of rodent host species and spillover our recent epidemiological survey conducted in mexico for hantavirus infection, we identified three distinct viruses circulating in mexican wild rodents, namely montano virus (mtnv), huitzilac virus (huiv), and carrizal virus (carv). to gain a detailed understanding of hantavirus epidemiology and its associated hosts, 410 rodents were captured at eight collecting points in morelos and guerrero, mexico, and examined for hantavirus seroprevalence, the presence of viral rna, and rodent host spec ...201222750131
cross-transmission studies with eimeria arizonensis-like oocysts (apicomplexa) in new world rodents of the genera baiomys, neotoma, onychomys, peromyscus, and reithrodontomys (muridae).cross-transmission experiments were performed using oocysts of an eimeria arizonensis-like coccidian from peromyscus leucopus and peromyscus truei, an e. arizonensis-like coccidian from reithrodontomys fulvescens, eimeria baiomysis and eimeria taylori from baiomys taylori, eimeria albigulae from neotoma albigula, and eimeria onychomysis from onychomys spp., between representatives of the above host genera. the e. arizonensis-like coccidian from r. fulvescens infected reithrodontomys megalotis, r ...19921597781
eimerians in harvest mice, reithrodontomys spp., from mexico, california and new mexico, and phenotypic plasticity in oocysts of eimeria arizonensis.between may 1979 and august 1991, 48.7% (57/117) of the harvest mice (reithrodontomys spp.) examined from 10 localities in mexico, california and new mexico had coccidian oocysts in their feces. a total of 46.7% (49/105) of the reithrodontomys megalotis examined were positive for coccidian oocysts; this included samples from five states in mexico (47.1%, 8/17), three counties in california (66.7%, 4/6) and two counties in new mexico (45.1%, 37/82); 66.7% (8/12) of the reithrodontomys montanus fr ...19921522549
introduced rats and an endemic roundworm: does rattus rattus contribute to baylisascaris procyonis transmission in california?the introduced black rat, rattus rattus, occurs throughout the native range of the raccoon roundworm, baylisascaris procyonis, and might incorporate into its life cycle if rats consume parasite eggs, acquire viable infections, and are eaten by raccoons. although rats forage at raccoon latrines, their role in b. procyonis transmission remains unknown. here i tested the potential for rats to amplify b. procyonis transmission in california by surveying wild rodents for b. procyonis and conducting s ...201728732456
impact of sylvatic plague vaccine on non-target small rodents in grassland ecosystems.oral vaccination is an emerging management strategy to reduce the prevalence of high impact infectious diseases within wild animal populations. plague is a flea-borne zoonosis of rodents that often decimates prairie dog (cynomys spp.) colonies in the western usa. recently, an oral sylvatic plague vaccine (spv) was developed to protect prairie dogs from plague and aid recovery of the endangered black-footed ferret (mustela nigripes). although oral vaccination programs are targeted toward specific ...201829744628
a tale of two valleys: disparity in sin nombre virus antibody reactivity between neighboring mojave desert communities.hantaviruses are a group of globally distributed rodent-associated viruses, some of which are responsible for human morbidity and mortality. sin nombre orthohantavirus, a particularly virulent species of hantavirus associated with peromyscus spp. mice, is actively monitored by the department of public health in california (cdph). recently, cdph documented high (40%) seroprevalence in a potentially novel reservoir species, the cactus mouse (peromyscus eremicus) in death valley national park.201930932773
demography of the salt marsh harvest mouse (reithrodontomys raviventris halicoetes) and associated rodents in tidal and managed wetlands.suisun marsh (solano county, california) is the largest contiguous marsh remaining on the west coast of the united states, and makes up approximately 10% of the wetlands remaining in the san francisco estuary. suisun marsh has been safeguarded from development through the operation of over 100 privately owned waterfowl hunting clubs, which manage for diked waterfowl habitat. however, this management-and the subsequent loss of tidal influence-has been considered harmful for some species, includin ...202032099266
small mammal community ecology : changes in species diversity in response to manipulated productivity.the abundance of food in natural 1-ha plot of shortgrass prairie was artificially manipulated by adding alfalfa pellets and whole oats on a regular schedule. the small mammal species naturally inhabiting the manipulated food plot did not respond in either their density or weight to the supplemented food. however, a new specialized seed-eating species, dipodomys ordii, invaded the food plot and persisted in relatively high density. as a result of this colonization, species diversity was significa ...197828309543
isotopic niche variation from the holocene to today reveals minimal partitioning and individualistic dynamics among four sympatric desert mice.species interact with each other and their environment over a range of temporal scales, yet our understanding of resource partitioning and the mechanisms of species coexistence is largely restricted to modern time-scales of years to decades. furthermore, the relative magnitudes of inter- vs. intraspecific variation in resource use are rarely considered, despite the potential for the latter to influence a species' ability to cope with changing environmental conditions. modern desert rodent commun ...201829048750
demography of the western harvest mouse, reithrodontomys megalotis, in eastern kansas.reithrodontomys megalotis was live-trapped on three open field grids in eastern kansas from august 1979 to august 1982. one grid was a control on which normal demography was monitored, and two were experimental grids where periodic removal of residents allowed the investigation of the demographic and fitness consequences of emigration. popullations on the control grid showed an annual cycle in numbers, reaching peaks in density during the winter of each year, falling to low densities during the ...198828312689
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