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survey of q-fever agglutinins in birds and small rodents in northern california, 1975-76.serum samples from 15 species of rodents and 33 species of birds were tested for agglutinins against coxiella burnetii by the microagglutination test. of 759 rodents tested, 21 (3%) were seropositive. antibody positive rodents included muskrats, ondatra zebethica, (11%), rattus spp. (10%), beechey ground squirrels, otospermophilus beecheyi, (6%), wood rats, neotoma fuscipes, (5%), and peromyscus spp. (2%). of 583 birds tested, 118 (20%) were seropositive. this included white crowned sparrows, zo ...1979522220
first isolation of borrelia burgdorferi in southern california.the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was isolated from the blood of a dusky-footed wood rat, neotoma fuscipes baird, in the san bernardino mountains of southern california. antigenic, protein, and molecular analyses demonstrated that the isolate varied slightly from most isolates of b. burgdorferi from northern california and was clearly distinct from other species of borrelia that are endemic to the state. this is the first reported iso ...19921625299
wood rats and kangaroo rats: potential reservoirs of the lyme disease spirochete in california.the etiologic agent of lyme disease, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was isolated repeatedly from dusky-footed wood rats, neotoma fuscipes baird, and california kangaroo rats, dipodomys californicus merriam, in northern california. all animals were collected in a region endemic for lyme disease but for which the natural reservoir of b. burgdorferi was unknown. similar attempts to isolate spirochetes from lizards, other species of rodents, jack rabbits, and deer ...19911875357
serologic evidence of yersinia pestis infection in small mammals and bears from a temperate rainforest of north coastal california.from 1983 to 1985, 463 serum samples from 11 species of mammals in redwood national park (rnp) (california, usa) were evaluated for antibodies to yersinia pestis by the passive hemagglutination method. yersinia pestis antibodies occurred in serum samples from 25 (36%) of 69 black bears (ursus americanus), one (50%) of two raccoons (procyon lotor), five (3%) of 170 dusky-footed woodrats (neotoma fuscipes), and one (less than 1%) of 118 deer mice (peromyscus maniculatus). two hundred seventy-three ...19892915403
effects of the microclimate on parasitic nest mites of the dusky footed wood rat, neotoma fuscipes baird. 19685690605
genetic diversity among borrelia burgdorferi isolates from wood rats and kangaroo rats in california.twenty-nine borrelia burgdorferi isolates, obtained from dusky-footed wood rats (neotoma fuscipes) and california kangaroo rats (dipodomys californicus) in california, were analyzed genetically. chromosomal dna was examined by restriction endonuclease analysis (rea) and gene probe restriction fragment length polymorphism. pulsed-field gel electrophoresis was used to analyze the plasmid profiles of the isolates. rea, the method with the greatest discrimination, disclosed 24 distinct restriction p ...19937905880
natural and experimental borrelia burgdorferi infections in woodrats and deer mice from california.sequestration of spirochetes and concurrent histopathologic lesions were evaluated in tissues of borrelia burgdorferi-infected dusky-footed woodrats (neotoma fuscipes) and deer mice (peromyscus maniculatus). rodents were either wild-caught and naturally infected or were experimentally infected by tick bite, by intramuscular (i.m.) injection of cultured spirochetes, or by i.m. injection of tick suspensions. samples of host tissues, including skin, blood, ear, brain, eye, heart, lung, liver, splee ...19947933283
modifications of a cholinesterase method for determination of erythrocyte cholinesterase activity in wild mammals.a method to determine erythrocyte cholinesterase (che) activity was modified for use in wild mammals. erythrocyte che of california voles (microtus californicus) was primarily acetylcholinesterase (ache), which was similar to the brain and unlike plasma which was primarily butyrylcholinesterase (bche). triplicate erythrocyte ache analyses from individual animals of several species of wild rodents revealed a mean coefficient of variation of 8.7% (sd = 4.3%). erythrocyte che activity of several wi ...19948028108
reservoir competence of four chaparral-dwelling rodents for borrelia burgdorferi in california.aspects of the reservoir competence of four rodents for the lyme disease spirochete, borrelia burgdorferi, were evaluated in california. rodents were live-trapped and ear-punch biopsies were cultured during each season. a second set of biopsies was cultured from representative individuals after 2-3 weeks of captivity and the results of culturing biopsies taken on both dates were compared with the results of feeding ixodes pacificus larvae on hosts xenodiagnostically. the prevalence of infections ...19968651378
ixodes (ixodes) jellisoni and i. (i.) neotomae (acari:ixodidae): descriptions of the immature stages from california.nymphal and larval stages of ixodes (ixodes) jellisoni cooley & kohls and i. (i.) neotomae cooley are described for the first time. these 2 tick species occur only in the western united states, predominantly in california. the primary host for i. jellisoni is the california kangaroo rat, dipodomys californicus (merriam); that for i. neotomae is the dusky-footed woodrat, neotoma fuscipes baird. the etiologic agent of lyme disease borrelia burgdorferi johnson, schmidt, hyde, steigerwalt & brenner ...19968667376
evaluation of permethrin-impregnated cotton balls as potential nesting material to control ectoparasites of woodrats in california.the dusky-footed woodrat, neotoma fuscipes baird is a natural reservoir of the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, in california. to investigate the potential of host-targeted insecticide to control the tick vectors of b. burgdorferi, permethrin-impregnated or untreated cotton balls were distributed in metal cylinders as potential nesting material adjacent to 95 woodrat houses in chaparral-covered rangeland. laboratory experiments demonstra ...19968667381
factors affecting the seasonal abundance of ground squirrel and wood rat fleas (siphonaptera) in san diego county, california.abiotic and biotic factors affecting the seasonal abundance of 3 species of sylvatic fleas on their hosts were examined at 7 sites in san diego county, california. indices for oropsylla (diamanus) montana (baker) were usually highest on spermophilus beecheyi nudipes (huey) when < 18.4 degrees c (october-december), whereas those for hoplopsyllus anomalus (baker) were highest when > 18.4 degrees c (july-september). o. montana was affected most by ambient temperature (inversely for the coastal site ...19968840686
ixodid ticks (acari, ixodidae) found in san diego county, california.in san diego county, california, 11 species of ixodid ticks were collected from vegetation and/or from small and large mammals, and/or found parasitizing humans. adults of the pacific coast tick, dermacentor occidentalis, were the most abundant tick collected from vegetation, with peak numbers occurring during march and april. adults of the western black-legged tick, ixodes pacificus, were the second most abundant, with peaks occurring during february and march. eight species of ticks were found ...199910436879
isolation of borrelia burgdorferi from neotoma fuscipes, peromyscus maniculatus, peromyscus boylii, and ixodes pacificus in oregon.the number of lyme disease cases in oregon has increased in recent years despite the fact that the pathogen, borrelia burgdorferi, has never been isolated in the state. rodent and tick surveys were undertaken in 1997 to isolate and characterize strains of b. burgdorferi from oregon and to identify potential reservoirs and vectors of lyme disease. borrelia burgdorferi was isolated from neotoma fuscipes, peromyscus maniculatus, p. boylii, and ixodes pacificus. both n. fuscipes and p. maniculatus w ...199910466976
dusky-footed wood rats (neotoma fuscipes) as reservoirs of granulocytic ehrlichiae (rickettsiales: ehrlichieae) in northern california.dusky-footed wood rats (neotoma fuscipes) and peromyscus sp. mice (p. maniculatus and p. truei) were collected from one site in placer county, one site in santa cruz county, and two sites in sonoma county in northern california. serum or plasma samples from 260 rodents were tested for antibodies to the agent of human granulocytic ehrlichiosis. of these, samples from 25 wood rats (34% of those tested) and 10 (8%) peromyscus sp. mice were found to be seropositive, but only those from one site. pcr ...199910488199
ecology of borrelia burgdorferi in ticks (acari: ixodidae), rodents, and birds in the sierra nevada foothills, placer county, california.this study examined the prevalence of borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner in host-seeking adult and nymphal ixodes pacificus cooley & kohls and estimated the i. pacificus infestation and b. burgdorferi infection of rodent and avian hosts in the western sierra nevada foothills of northern california. additionally, we identified species likely to participate in an enzootic cycle for b. burgdorferi in this yellow pine transition habitat. evidence of infection with b. b ...200011126549
field trial of systemically delivered arthropod development-inhibitor (fluazuron) used to control woodrat fleas (siphonaptera: ceratophyllidae) and ticks (acari: ixodidae).an orally delivered arthropod development-inhibitory (fluazuron) was evaluated for its potential to reduce the number of flea and tick vectors found on the dusky-footed woodrat neotoma fuscipes baird, a reservoir host important in disease enzootiology in northern california. pigmented bait cubes containing fluazuron were distributed monthly to woodrat nests in a chaparral habitat for 1 yr. when compared with control woodrats, the numbers of fleas [primarily orchopeas sexdentatus (baker)] on trea ...200111268695
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
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
description and epidemiology of theileria youngi n. sp. from a northern californian dusky-footed woodrat (neotoma fuscipes) population.an epidemiologic study designed to identify the small mammal reservoir for the zoonotic wa1-type babesial parasite resulted in the discovery of a small, intraerythrocytic piroplasm in smeared blood from dusky-footed woodrats (neotoma fuscipes) in northern california. the woodrat parasites were isolated and compared to other piroplasm parasites based on their morphology, antigenicity, and genetic characteristics. these studies indicated that the woodrat parasites were not the wa1-type babesial ag ...200111318567
persistent infection in neotoma fuscipes (muridae: sigmodontinae) with ehrlichia phagocytophila sensu lato.dusky-footed wood rats (neotoma fuscipes baird) and two species of peromyscus mice (p. maniculatus wagner and p. truei shufeldt) were collected over a 16-month period from three sites in sonoma county, california. blood was collected from 93 wood rats and 177 mice and serum or plasma was tested for seroreactivity with ehrlichia phagocytophila sensu lato (also known as the human granulocytic ehrlichiosis agent). thirty-five (37.6%) wood rats and 15 (8.5%) mice were seropositive. positive neotoma ...200111693866
experimental infection of dusky-footed wood rats (neotoma fuscipes) with ehrlichia phagocytophila sensu lato.dusky-footed wood rats, neotoma fuscipes, have been implicated in the natural maintenance of ehrlichia phagocytophila sensu lato, the agent of human granulocytic ehrlichiosis (hge), in northern california based on high seroprevalence and amplification of e. phagocytophila s.l. dna from wood rat blood. in order to further assess granulocytic ehrlichiosis in wood rats, we examined wild-caught wood rats for infection and then performed experimental intra-peritoneal infections with e. phagocytophila ...200211838215
phylogeographical structure and regional history of the dusky-footed woodrat, neotoma fuscipes.the dusky-footed woodrat, neotoma fuscipes, is a medium-sized rodent that inhabits low elevation woodland habitats along the pacific coast of north america from oregon, throughout california and into baja california. analyses of mitochondrial sequence variation throughout the distribution reveal substantial phylogeographical structure within n. fuscipes. the major mitochondrial lineages are largely concordant with previously identified morphological subdivisions within the taxon. the geographica ...200211856424
flea, rodent, and plague ecology at chuchupate campground, ventura county, california.chuchupate campground in ventura county, california, was closed to the public for 18 years (1982 to 2000) because of uncontrolled vector fleas and persistent plague antibody titers in rodents. the primary purpose of this study was to clarify the plague ecology of chuchupate campground by identifying involved rodents and their vector fleas and by determining many of their ecological parameters: abundance, flea and host preferences and diversities, and flea seasonality. rodents and fleas were iden ...200212125863
hematology and serum biochemistry values of dusky-footed wood rat (neotoma fuscipes).serum chemistry values and complete blood counts were determined for 36 wild dusky-footed wood rats (neotoma fuscipes) from sonoma and western yolo county, california (usa) in summer 1999 and spring 2001. all wood rats had adequate body condition and were hydrated. many hematologic and biochemical values were comparable to those for house rat (rattus rattus). there were differences between wood rats tested immediately after capture (those from yolo county) and after a week of habituation in the ...200212238375
vector competence of ixodes pacificus and i. spinipalpis (acari: ixodidae), and reservoir competence of the dusky-footed woodrat (neotoma fuscipes) and the deer mouse (peromyscus maniculatus), for borrelia bissettii.we investigated the experimental vector competence of ixodes pacificus cooley and kohls and ixodes spinipalpis hadwen and nuttall, and the reservoir competence of the dusky-footed woodrat (neotoma fuscipes baird) and the deer mouse (peromyscus maniculatus [wagner]), for borrelia bissettii postic, marti ras, lane, hendson, and baranton. both rodent species are capable reservoirs for b. bissettii; infection rates for i. pacificus or i. spinipalpis nymphs fed as larvae on infected animals ranged fr ...200312943110
element content in tissues of four rodent species sampled in the geysers geothermal steamfield.liver and kidney tissue samples from four rodent species collected in the geysers geothermal steamfield of northern california were analyzed for content of 28 elements. element concentrations in samples from the developed region of the geysers were compared with samples from undeveloped reference regions to determine the influence of geothermal power development on element content in small mammal tissues. eight elements (b, ca, cu, mg, mn, p, sr, ti) were enriched in samples from the geysers, 12 ...198915092429
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
habitat-related variation in infestation of lizards and rodents with ixodes ticks in dense woodlands in mendocino county, california.during the spring and early summer of 2002, we examined the relative importance of borrelia-refractory lizards (sceloporus occidentalis, elgaria spp.) versus potential borrelia burgdorferi sensu lato (s.l.)-reservoirs (rodents) as hosts for ixodes pacificus immatures in 14 woodland areas (six oak, five mixed oak/douglas fir, and three redwood/tanoak areas) distributed throughout mendocino county, california. lizards were estimated to serve as hosts for 93-98% of all larvae and > or =99.6% of all ...200415347025
the roles of birds, lizards, and rodents as hosts for the western black-legged tick ixodes pacificus.we compared the infestation by ixodid ticks of lizards, rodents, and birds collected simultaneously within areas representing common habitat types in mendocino county, ca. lizards were infested only by ixodes pacificus cooley and kohls, birds by i. pacificus and haemaphysalis leporispalustris (packard), and rodents by i. pacificus, i. spinipalpis hadwen and nuttall, i. woodi bishopp, dermacentor occidentalis marx, and d. variabilis (say). infestation by i. pacificus larvae and nymphs of lizards ...200415709249
sylvatic maintenance of borrelia burgdorferi (spirochaetales) in northern california: untangling the web of transmission.lyme borreliosis is associated with several genospecies of borrelia burgdorferi sensu lato (s.l.) (spirochaetales), but human disease has been associated only with borrelia burgdorferi sensu stricto (s.s.) johnson, schmid, hyde, steigerwalt & brenner in the western united states. restriction fragment length polymorphism (rflp) analysis of rrf-rrl amplicons from 124 tick and mammalian isolates from various habitats yielded 13 rflp patterns. of these patterns, six were patterns previously associat ...200616892634
detoxification rates of wild herbivorous woodrats (neotoma).the detoxification systems of mammalian herbivores are thought to have evolved in response to the ingestion of plant secondary compounds. specialist herbivores consume high quantities of secondary compounds and are predicted to have faster rates of phase 1 detoxification compared to generalist herbivores. we tested this hypothesis by comparing the performances of a specialist (neotoma fuscipes) and generalist (neotoma lepida) herbivore using hypnotic state assays. herbivores foraging in nature w ...200616962347
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
fine-scale phenotypic change across a species transition zone in the genus neotoma: disentangling independent evolution from phylogenetic history.zones of secondary contact between closely related species provide a rare opportunity to examine evidence of evolutionary processes that reinforce species boundaries and/or promote diversification. here, we report on genetic and morphological variation in two sister species of woodrats, neotoma fuscipes and n. macrotis, across a 30-km transition zone in the sierra nevada of california. we assessed whether these lineages readily hybridize, and whether their morphology suggests ecological interact ...200717927780
survey for zoonotic rickettsial pathogens in northern flying squirrels, glaucomys sabrinus, in california.epidemic typhus, caused by rickettsia prowazekii, is maintained in a southern flying squirrel (glaucomys volans) sylvatic cycle in the southeastern united states. the northern flying squirrel (glaucomys sabrinus) has not been previously associated with r. prowazekii transmission. a second rickettsial pathogen, anaplasma phagocytophilum, infects dusky-footed woodrats (neotoma fuscipes) and tree squirrels in northern california. because northern flying squirrels or their ectoparasites have not bee ...200717984264
differential exposure to anaplasma phagocytophilum in rodent species in northern california.anaplasma phagocytophilum is a zoonotic tick-borne rickettsial pathogen that causes granulocytic anaplasmosis (ga) in humans, horses, and dogs. in california, dusky-footed woodrats (neotoma fuscipes) are a putative reservoir host, and ixodes pacificus is a vector for transmission from rodents to humans, dogs, and horses. cases are clustered in coastal and sierra nevada foothill regions, but not necessarily in proximity to infected woodrats. this study was designed to compare exposures and active ...200818047398
serologic evidence of a rickettsia akari-like infection among wild-caught rodents in orange county and humans in los angeles county, california.we detected antibodies reactive with rickettsia akari, the etiologic agent of rickettsialpox in humans and in 83 of 359 (23%) rodents belonging to several species, collected in orange county, ca. reciprocal antibody titers >1:16 to r. akari were detected in native mice and rats (peromyscus maniculatus, p. eremicus, and neotoma fuscipes) and in old world mice and rats (mus musculus, rattus rattus, and r. norvegicus), representing the first time that antibodies reactive with this agent have been d ...200718260508
anaplasma phagocytophilum infection in small mammal hosts of ixodes ticks, western united states.a total of 2,121 small mammals in california were assessed for anaplasma phagocytophilum from 2006 through 2008. odds ratios were >1 for 4 sciurids species and dusky-footed woodrats. high seroprevalence was observed in northern sites. ten tick species were identified. heavily infested rodent species included meadow voles, woodrats, deer mice, and redwood chipmunks.200818598645
possible differential host tropism in anaplasma phagocytophilum strains in the western united states.despite organization into a single species, anaplasma phagocytophilum, of bacteria from diverse hosts, there is evidence that different hosts vary in susceptibility to local strains of this bacterial pathogen. in particular, there is evidence that clinical hosts (humans, horses, and dogs) in the western part of the united states may be infected with strains of bacteria that differ from those in the reported wildlife reservoir, the dusky-footed woodrat. there is a lack of spatial overlap between ...200819120182
reservoir competence of the redwood chipmunk (tamias ochrogenys) for anaplasma phagocytophilum.granulocytic anaplasmosis (ga) is an emerging tick-transmitted disease that persists in rodent- ixodes ricinus-complex tick cycles across the holarctic. although the putative reservoir for anaplasmosis in the western united states is the dusky-footed woodrat (neotoma fuscipes), this rodent was not shown reservoir-competent because of failure of infection from woodrats to other animals via ticks. redwood chipmunks are common in habitats where anaplasma phagocytophilum is common, have high pcr- an ...200919327022
effect of prescribed fire for tick control in california chaparral.prescribed fire was investigated as a method for controlling ixodid and argasid ticks in chaparral habitats in northern california. two experimental and two adjacent control plots within a wildlife preserve were monitored for 1 yr postburn. ticks were collected by flagging vegetation, by co2-baited pitfall trap, and by live-trapping rodents. twice as many rodents were caught at control sites compared with burn sites and no dusky-footed woodrats, neotoma fuscipes baird, were found in the treatmen ...200919769046
transmission cycles of borrelia burgdorferi and b. bissettii in relation to habitat type in northwestern california.this study was undertaken to determine which rodent species serve as primary reservoirs for the lyme disease spirochete borrelia burgdorferi in commonly occurring woodland types in inland areas of northwestern california, and to examine whether chaparral or grassland serve as source habitats for dispersal of b. burgdorferi- or b. bissettii-infected rodents into adjacent woodlands. the western gray squirrel (sciurus griseus) was commonly infected with b. burgdorferi in oak woodlands, whereas exam ...200920514140
the dusky-footed woodrat (neotoma fuscipes) is susceptible to infection by anaplasma phagocytophilum originating from woodrats, horses, and dogs.the dusky-footed woodrat (neotoma fuscipes) is the putative reservoir for anaplasma phagocytophilum in the western united states based on high prevalence of a. phagocytophilum genetic material detected by polymerase chain reaction (pcr), high antibody prevalence, and infestation with the vector tick ixodes pacificus. following inoculation of nine wild-caught woodrats with woodrat-, canine-, or equine-origin a. phagocytophilum, all became pcr-positive and seroconverted. however, when pcr-positive ...201020688687
effects of an invasive forest pathogen on abundance of ticks and their vertebrate hosts in a california lyme disease focus.invasive species, including pathogens, can have important effects on local ecosystems, including indirect consequences on native species. this study focuses on the effects of an invasive plant pathogen on a vertebrate community and ixodes pacificus, the vector of the lyme disease pathogen (borrelia burgdorferi) in california. phytophthora ramorum, the causative agent of sudden oak death, is a non-native pathogen killing trees in california and oregon. we conducted a multi-year study using a grad ...201020941513
a new anoplocephalid cestode, andrya neotomae, from the wood rat neotoma fuscipes. 194621022148
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 ...201121506825
nidicolous ticks of small mammals in anaplasma phagocytophilum-enzootic sites in northern california.ixodes spp. tick-borne zoonotic diseases are present across the holarctic in humans, domestic animals, and wildlife. small mammals are reservoirs for the rickettsial pathogen anaplasma phagocytophilum and tick vectors may include catholic-feeding bridge vectors as well as host-specialist or nidicolous ticks. far western north american communities in which a. phagocytophilum is maintained are complex ecologically, with multiple reservoir host and tick species, multiple strains of the bacterial pa ...201121686062
physiology on a landscape scale: plant-animal interactions.we explore in this paper how animals can be affected by variation in climate, topography, vegetation characteristics, and body size. we utilize new spatially explicit state-of-the-art models that incorporate principles from heat and mass transfer engineering, physiology, morphology, and behavior that have been modified to provide spatially explicit hypotheses using gis. we demonstrate how temporal and spatial changes in microclimate resulting from differences in topography and vegetation cover a ...200221708738
temporal patterns of tick-borne granulocytic anaplasmosis in california.granulocytic anaplasmosis (ga) is a tick-borne emerging infectious disease caused by the bacterium anaplasma phagocytophilum. from fall 2005 to spring 2007, a. phagocytophilum infection prevalence in small mammals and tick abundance were monitored at 4 study sites in coastal california. the abundance of different life stages of questing ixodes pacificus ticks fluctuated seasonally with the number of adults peaking december to february, nymphs peaking may to july, and larvae peaking april to june ...201121771541
avian hosts of ixodes pacificus (acari: ixodidae) and the detection of borrelia burgdorferi in larvae feeding on the oregon junco.larval and nymphal western blacklegged tick, ixodes pacificus cooley & kohls (acari: ixodidae), were collected from birds, rodents, and lizards at quail ridge reserve located in napa county in northwestern california. species from three vertebrate classes were sampled simultaneously from two transects during two consecutive spring seasons. feeding larval and nymphal ticks were removed and preserved for counting, examination and testing for the presence of borrelia burgdorferi johnson, schmid, hy ...201121845945
impacts of an introduced forest pathogen on the risk of lyme disease in california.global changes such as deforestation, climate change, and invasive species have the potential to greatly alter zoonotic disease systems through impacts on biodiversity. this study examined the impact of the invasive pathogen that causes sudden oak death (sod) on the ecology of lyme disease in california. the lyme disease bacterium, borrelia burgdorferi, is maintained in the far western united states by a suite of animal reservoirs including the dusky-footed woodrat (neotoma fuscipes) and deer mo ...201222607076
remarkable diversity of tick or mammalian-associated borreliae in the metropolitan san francisco bay area, california.the diversity of lyme disease (ld) and relapsing fever (rf)-group spirochetes in the metropolitan san francisco bay area in northern california is poorly understood. we tested ixodes pacificus, i. spinipalpis, and small mammals for presence of borreliae in alameda county in the eastern portion of san francisco bay between 2009 and 2012. analyses of 218 borrelia burgdorferi sensu lato (bb sl) culture or dna isolates recovered from host-seeking i. pacificus ticks revealed that the human pathogen b ...201425129859
parasite prevalence and community diversity in sympatric and allopatric populations of two woodrat species (sigmodontinae: neotoma) in central california.patterns of host-parasite association may vary across the landscape in part because of host and parasite diversity, divergence, local ecology, or interactions among these factors. in central coastal california, we quantified parasite prevalence, infection intensity, and diversity in two sister species of woodrats (neotoma fuscipes and neotoma macrotis) where the species co-occur (sympatry) and where each species exists alone (allopatry). in feces from 50 adults we identified seven taxa: the prot ...201525574805
a real-time pcr assay for differentiating pathogenic anaplasma phagocytophilum from an apathogenic, woodrat-adapted genospecies from north america.anaplasma phagocytophilum is a tick-transmitted bacterial pathogen of humans and animals comprising strains that cause clinical disease in people, dogs and horses (the pathogenic a. phagocytophilum "genospecies") and more distantly related strains. a rodent-adapted genospecies named du1, found primarily in woodrats, is unable to infect horses. we developed a real-time pcr (rt-pcr) assay, which targets an 85 base pair region of the ank gene and is specific for the pathogenic genospecies of a. pha ...201526188998
fine-scale genetic structure of woodrat populations (genus: neotoma) and the spatial distribution of their tick-borne pathogens.dusky-footed woodrats are territorial cricetid rodents that individually occupy large stick houses from which they foray to gather food, find mates, and engage in other activities. these rodents are often bitten by ixodes spp. ticks and are reservoirs of some strains of tick-borne bacterial pathogens such as anaplasma phagocytophilum and borrelia burgdorferi. limited dispersal by hosts and vectors could create fine-scale population structure where related hosts and pathogen exposure are co-distr ...201626530982
borrelia bissettiae sp. nov. and borrelia californiensis sp. nov. prevail in diverse enzootic transmission cycles.two borrelia species, borrelia bissettiae sp. nov. and borrelia californiensis sp. nov., were first described by postic and co-workers (postic et al., 2007; postic et al., 1998) based on genetic analyses of several loci. multilocus sequence analysis (mlsa) of eight housekeeping loci confirmed that these two borrelia genospecies are distinct members of the b. burgdorferi s. l. complex (margos et al., 2010). b. bissettiae sp. nov. initially was described in transmission cycles involving neotoma fu ...201626813420
molecular epidemiology of bartonella species isolated from ground squirrels and other rodents in northern california.bartonella spp. are endemic in wild rodents in many parts of the world. a study conducted in two northern california counties (sonoma and yolo) sampling california ground squirrels (otospermophilus beecheyi) and four other rodent species (peromyscus maniculatus, p. boylii, p. truei and neotoma fuscipes) led to the isolation of small gram-negative bacilli which were identified as bartonella spp. based on colony morphology, polymerase chain reaction-restriction fragment length polymorphism (pcr-rf ...201627245290
seasonal changes in the water metabolism of woodrats.dusky-footed woodrats (neotoma fuscipes) and desert woodrats (n. lepida) experience pronounced seasonal variations in the aridity of their habitats. the effects of seasonal aridity upon the water conserving abilities of these species were assessed through measurements of water conserving abilities and kidney structure of animals captured in summer and winter, and through measurements of animals' abilities to acclimate to differing water availabilities in the laboratory.urine concentrating abilit ...197928308890
adaptation to oak and other fibrous, phenolic-rich foliage by a small mammal, neotoma fuscipes.neotoma fuscipes, a small mammalian herbivore with apparently generalized food habits, was laboratory tested to determine its degree of dietary specialization. woodrats from both oak woodland and coastal sage communities preferred quercus agrifolia leaves (containing 40% phenolics and about 16% condensed tannin) over foliage from other dominant species. approximately one-third of the oak phenolics and less than 10% of the oak condensed tannin remained in the feces. their performance on pure oak ...198328310547
differential effects of climate on survival rates drive hybrid zone movement.climate change has been implicated as driving shifts of hybridizing species' range limits [1, 2]. whether and how much hybrid zones move depends on the relative fitness of hybridzing species under changing conditions [3, 4]. however, fitness is rarely linked to both climatic conditions and movement of hybrid zones, such that the relationship between climate change and hybrid zone dynamics remains tenuous [5]. here we report how interactions between climate (seasonal precipitation) and competitor ...201729225026
speciation along a shared evolutionary trajectory.groups of organisms-whether multiple species or populations of a single species-can differ in several non-exclusive ways. for example, groups may have diverged phenotypically, genetically, or in the evolutionary responses available to them. we tested for the latter of these-response divergence-between 2 species of woodrats: neotoma fuscipes and neotoma macrotis. based on random skewers analyses we found that, despite being well differentiated both phenotypically and genetically, n. fuscipes and ...201629491940
spatial clustering of borrelia burgdorferi sensu lato within populations of allen's chipmunks and dusky-footed woodrats in northwestern california.the ecology of lyme borreliosis is complex in northwestern california, with several potential reservoir hosts, tick vectors, and genospecies of borrelia burgdorferi sensu lato. the primary objective of this study was to determine the fine-scale spatial distribution of different genospecies in four rodent species, the california ground squirrel (otospermophilus beecheyi), northern flying squirrel (glaucomys sabrinus), dusky-footed woodrat (neotoma fuscipes), and allen's chipmunk (neotamias senex) ...201829634745
borrelia miyamotoi infections in small mammals, california, usa.surveillance to investigate the wildlife-vector transmission cycle of the human pathogen borrelia miyamotoi in california, usa, revealed infections in dusky-footed woodrats, brush mice, and california mice. phylogenetic analyses suggest a single, well-supported clade of b. miyamotoi is circulating in california.201830457525
borrelia burgdorferi and anaplasma phagocytophilum genospecies in northern california.the sensu lato (s.l.) complexes of borrelia burgdorferi and anaplasma phagocytophilum include pathogenic genospecies each with distinct ecologies in northern california, yet, most work conflates the genospecies of each pathogen into one sensu lato species. detailed understanding of the differences in geographic distributions and ecology among genospecies is lacking. we aimed to evaluate whether two b. burgdorferi and two a. phagocytophilum genospecies in high-risk locations in coastal northern c ...202032155394
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