| new host and locality records of coccidia (apicomplexa: eimeriidae) from rodents in the southwestern and western united states. | one hundred forty-seven murid and heteromyid rodents were collected from various sites in the southwestern and western united states (arizona, colorado, new mexico, texas, and utah) and baja california norte, mexico, and their feces were examined for coccidial parasites. of these, 53 (36%) were infected with at least 1 coccidian; 45 of 53 (85%) of the infected rodents harbored only 1 species of coccidian. infected rodents included: 10 of 22 (45%) neotoma albigula, 3 of 11 (27%) neotoma floridana ... | 1991 | 1779282 |
| lyme disease in california: interrelationship of ixodid ticks (acari), rodents, and borrelia burgdorferi. | the association of immature ixodid ticks, several species of rodents, and the lyme disease spirochete, borrelia burgdorferi johnson, schmid, hyde, steigerwalt & brenner, was studied in two habitats in northern california in spring and summer 1985 and year-round in 1986. a total of 428 rodents were collected from ecotonal chaparral and a woodland-grass-rock outcrop; the former habitat yielded six species, the latter three species. the deer mouse, peromyscus maniculatus (wagner), and the piñon mou ... | 1991 | 1941942 |
| serological survey of prospect hill virus infection in indigenous wild rodents in the usa. | we found serological evidence of infection with prospect hill virus, a hantaan-like virus isolated from meadow voles (microtus pennsylvanicus), in microtine and cricetid rodents trapped in maryland, west virginia, minnesota and california, usa. fluorescent antibodies were detected in sera from m. pennsylvanicus (74/277), m. californicus (39/185), clethrionomys gapperi (5/51), peromyscus maniculatus (4/22) and p. truei (1/11). sera from seropositive p. maniculatus contained neutralizing antibodie ... | 1987 | 2895510 |
| 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 ... | 1989 | 2915403 |
| isolation and initial characterization of a newfound hantavirus from california. | a fatal case of hantavirus pulmonary syndrome (hps) in northern california prompted our attempt to isolate viruses from local rodents. from tissues of two deer mice, peromyscus maniculatus, two hantaviruses (convict creek virus 107 and 74, cc107 and cc74) were established in cell culture. viral antigens, proteins, and rnas of the first and archetypical isolate (cc107) were examined, and portions of the medium (m) and small (s) genome segments of both isolates were sequenced. antigenically, cc107 ... | 1995 | 7856107 |
| complete nucleotide sequences of the m and s segments of two hantavirus isolates from california: evidence for reassortment in nature among viruses related to hantavirus pulmonary syndrome. | we report the complete nucleotide sequence of the m and the s genome segments and a portion of the l segments of two hantavirus isolates from peromyscus maniculatus trapped in eastern california. the isolates, convict creek 107 and 74 (cc107 and cc74) are genetically similar to viruses known to cause hantavirus pulmonary syndrome in new mexico. cc107 and cc74 each have an m segment consisting of 3696 nucleotides with a coding potential of 1140 amino acids in the virus complementary-sense rna (cr ... | 1995 | 7856108 |
| short report: prevalence of hantavirus infection in rodents associated with two fatal human infections in california. | rodents living near two fatal human cases of hantavirus pulmonary syndrome in california were surveyed for evidence of hantavirus infection. seventeen (15%) (14 peromyscus maniculatus and one each of p. truei, eutamias minimus, and microtus californicus) of 114 rodents tested had evidence (enzyme-linked immunosorbent assay or polymerase chain reaction) of hantavirus infection. this suggests that peromyscus mice, and p. maniculatus in particular, may be the reservoir for the virus causing this ne ... | 1995 | 7872450 |
| 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 ... | 1994 | 7933283 |
| 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 ... | 1996 | 8619434 |
| coat color genetics of peromyscus: v. california blonde, a new recessive mutation in the deer mouse. | california blonde is a coat color mutation in the deer mouse (peromyscus maniculatus) discovered among descendants of wild-type animals collected on santa cruz island, california. the phenotype is produced by the presence of brown, rather than black, eumelanin in the pelage and skin. retinal pigmentation is also reduced. the condition is inherited as an autosomal recessive trait. the california blonde gene is nonallelic with the brown (b), blonde (bln), and platinum (plt) mutant genes in this sp ... | 1996 | 8904838 |
| experimental evaluation of rodent exclusion methods to reduce hantavirus transmission to humans in rural housing. | an experimental assessment of methods to reduce rodent infestations in rural housing was conducted in yosemite national park, california, sequoia/kings canyon national parks, california, and shenandoah national park, virginia. during pretreatment surveys, nearly all (63 of 68) selected units had past or ongoing rodent activity inside. active infestations were found in 58.8% of the units. peromyscus spp. represented 91.2% of all animals caught inside housing units. despite little harborage, roden ... | 1997 | 9158040 |
| seroepidemiologic studies of hantavirus infection among wild rodents in california. | a total of 4,626 mammals were serologically tested for antibodies to sin nombre virus. all nonrodent species were antibody negative. among wild rodents, antibody prevalence was 8.5% in murids, 1.4% in heteromyids, and < 0.1% in sciurids. of 1,921 peromyscus maniculatus (deer mice), 226 (11.8%) were antibody positive, including one collected in 1975. the highest antibody prevalence (71.4% of 35) was found among p. maniculatus on santa cruz island, off the southern california coast. prevalence of ... | 1997 | 9204301 |
| population dynamics of the deer mouse (peromyscus maniculatus) and sin nombre virus, california channel islands. | hantavirus pulmonary syndrome, first documented in 1993, is caused by sin nombre virus (snv), which is carried by the peromyscus species. in 1994, high snv antibody prevalence was identified in deer mice from two california channel islands. we sampled two locations on three islands to estimate mouse population density and snv prevalence. population flux and snv prevalence appear to vary independently. | 1997 | 9284383 |
| genetic reassortment among viruses causing hantavirus pulmonary syndrome. | in order to determine the frequency and characteristics of reassortment among viruses causing hantavirus pulmonary syndrome (hps), mixed infections were initiated in tissue culture by using two closely related strains of sin nombre virus, cc107 (from eastern california) and nmr11 (from new mexico), which share the same species of rodent host in nature, the deer mouse (peromyscus maniculatus). potential reassortant virus plaques were screened by multiplex rt-pcr, using primers specific for indivi ... | 1998 | 9501041 |
| ecology and demographics of hantavirus infections in rodent populations in the walker river basin of nevada and california. | to study the ecologic correlates of hantavirus in deer mice (peromyscus maniculatus), we sampled 114 sites in the walker river basin of nevada and california in 1995-1996. blood samples were tested for antibody to hantavirus, and a subset of samples was also tested for virus rna by reverse transcription-polymerase chain reaction. average prevalence of antibody-positive mice was 17%, with heavier males the most likely to be infected. antibody prevalence varied within repeatedly sampled sites from ... | 1998 | 9749642 |
| 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 ( ... | 1999 | 9988327 |
| vector competence of ixodes angustus (acari: ixodidae) for borrelia burgdorferi sensu stricto. | the vector competence of ixodes angustus for borrelia burgdorferi sensu stricto (s.s.) was investigated in the laboratory. the larval progeny of female ticks from washington state were placed on swiss-webster mice that had been inoculated intravenously with 10(8) spirochetes each of a californian isolate of b. burgdorferi. spirochetes were detected in 6 (12%) of 50 nymphs derived from larvae that had fed on these animals. ten nymphs from the same cohort of experimentally infected ticks were plac ... | 2000 | 10823359 |
| remote sensing and geographic information systems: charting sin nombre virus infections in deer mice. | we tested environmental data from remote sensing and geographic information system maps as indicators of sin nombre virus (snv) infections in deer mouse (peromyscus maniculatus) populations in the walker river basin, nevada and california. we determined by serologic testing the presence of snv infections in deer mice from 144 field sites. we used remote sensing and geographic information systems data to characterize the vegetation type and density, elevation, slope, and hydrologic features of ea ... | 2000 | 10827114 |
| 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 ... | 2000 | 11289675 |
| 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 ... | 2001 | 11310900 |
| 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 ... | 2004 | 15311469 |
| genealogical concordance and the specific status of peromyscus sejugis. | peromyscus sejugis, a peripheral isolate of peromyscus maniculatus, is a threatened taxon endemic to 2 small islands in the sea of cortés. although its insularity makes the specific recognition of p. sejugis inherently problematic, resolution of this problem has important conservation implications. to evaluate the specific validity and evolutionary history of p. sejugis, we compared sequence variation (nd3/nd4l/nd4) in mtdna for both island populations of p. sejugis with that for 8 populations o ... | 2006 | 16785280 |
| 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 ... | 2007 | 18260508 |
| 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 ... | 2010 | 20941513 |
| variable infection dynamics in four peromyscus species following experimental inoculation with baylisascaris procyonis. | wild rodents such as peromyscus spp. are intermediate hosts for the zoonotic ascarid baylisascaris procyonis (raccoon roundworm), and previous studies indicate peromyscus leucopus (white-footed mouse) likely serves an important role in parasite ecology. natural infections have been sporadically identified in a few peromyscus spp., but no data are available on differences in susceptibility among the many other species. we compared survival and infection dynamics of b. procyonis in 4 species ( p. ... | 2016 | 27351237 |
| the relationship between cardiopulmonary size and aerobic performance in adult deer mice at high altitude. | deer mice (peromyscus maniculatus sonoriensis) populations in the white mountains of eastern california are found across a substantial range of partial pressures of oxygen (po₂). reduction in po₂ at high altitude can have a negative impact on aerobic performance. we studied plastic changes in organ mass and volume involved in aerobic respiration in response to acclimation to high altitude, and how those changes are matched with aerobic performance measured by vo₂,max. adult deer mice born and ra ... | 2014 | 25147245 |
| 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 ... | 2011 | 21771541 |
| ants as first intermediate hosts of mesocestoides on san miguel island, usa. | this study tested the hypotheses that ants (formicidae) function as a first intermediate host of mesocestoides (cestoda: mesocestoididae) and that deer mice (peromyscus maniculatus) develop metacestode infections after ingesting cysticercoid or procercoid-infected ants. field studies were conducted at an island fox (urocyon littoralis littoralis) breeding facility located on san miguel island, california channel islands national park, usa, where > 40% of captive foxes were infected with adult me ... | 2005 | 15831116 |
| rodent-flea-plague relationships at the higher elevations of san diego county, california. | rodent-flea-plague relationships were examined at sites located at higher elevations of san diego county during 1991-2002. the most frequently sampled rodents were the california ground squirrel, spermophilus beecheyi, and white-footed mice, peromyscus spp. higher seasonal mean dependent variables (prevalences of squirrels and indices of o. montana), higher mean amounts of seasonal rainfall, and lower seasonal mean ambient temperatures were found at sites during 1991--1993 compared with 2000--20 ... | 2004 | 15707283 |
| effects of trichloroethylene and perchloroethylene on wild rodents at edwards air force base, california, usa. | effects of inhalation of volatilized trichloroethylene (tce) or perchloroethylene (pce) were assessed based on the health and population size of wild, burrowing mammals at edwards air force base (ca, usa). organic soil-vapor concentrations were measured at three sites with aquifer contamination of tce or pce of 5.5 to 77 mg/l and at two uncontaminated reference sites. population estimates of kangaroo rats (dipodomys merriami and d. panamintinus) as well as hematology, blood chemistry, and histop ... | 2004 | 15378993 |
| mhc class ii beta sequence diversity in the deer mouse (peromyscus maniculatus): implications for models of balancing selection. | we studied population polymorphism at a major histocompatibility complex (mhc) class ii beta gene in the deer mouse (peromyscus maniculatus). we found that: (i) a single population of p. maniculatus has significantly higher levels of dna and protein sequence diversity than worldwide samples from homologous genes in other taxa, including humans and mice; and (ii) the genealogy of allelic sequences in p. maniculatus deviates significantly from theoretical expectation under a model of symmetric bal ... | 2001 | 11903890 |
| experimental infection with western equine encephalomyelitis virus in wild rodents indigenous to kern county, california. | six species of rodents from kern county, california, were inoculated subcutaneously with western equine encephalomyelitis (wee) virus to determine their susceptibility to infection and their potential as natural hosts. ammospermophilus nelsoni, citellus beecheyi, dipodomys heermanni, dipodomys nitratoides, peromyscus maniculatus, and sciurus griseus were readily infected. infection was usually fatal in dipodomys species, c. beecheyi, and s. griseus, but was clinically inapparent in other species ... | 1974 | 4426699 |
| annual cyclicity of gall stone prevalence in deer mice (peromyscus maniculatus gambelii). | the prevalence of gall stones (100% cholesterol) in a deer mouse (peromyscus maniculatus) population located in siskiyou county, california (usa) was studied on a monthly basis from february 1985 through january 1988. during each year we documented a pronounced annual cyclicity with peak prevalence (31 to 53%) during the winter and low prevalence (2 to 3%) during late summer. gall stone prevalence was not related to sex or age of the animal. the earliest onset of gall stone production and the ma ... | 1989 | 2810546 |
| uptake of environmental contaminants by small mammals in pickleweed habitats at san francisco bay, california. | small mammals were live-trapped in pickleweed (salicornia virginica) habitats near san francisco bay, california in order to measure the uptake of several contaminants and to evaluate the potential effects of these contaminants on the endangered salt marsh harvest mouse (reithrodontomys raviventris). tissues of house mice (mus musculus), deer mice (peromyscus maniculatus), and california voles (microtus californicus) from nine sites were analyzed for chemical contaminants including mercury, sele ... | 1992 | 1586203 |
| effectiveness of rodenticides for managing invasive roof rats and native deer mice in orchards. | roof rats (rattus rattus) and deer mice (peromyscus maniculatus) are occasional pests of nut and tree fruit orchards throughout california and in many other parts of the usa and beyond. in general, the most practical and cost-effective control method for rodents in many agricultural environments is the use of rodenticides (toxic baits), but little or no information exists on the efficacy of current rodenticides in controlling roof rats and deer mice in orchards. therefore, our goals were to deve ... | 2014 | 24443051 |
| cranial morphological variation in peromyscus maniculatus over nearly a century of environmental change in three areas of california. | determining how species respond to prolonged environmental change is critical to understanding both their evolutionary biology and their conservation needs. in general, organisms can respond to changing environmental conditions by moving, by adapting in situ, or by going locally or globally extinct. morphological changes, whether plastic or adaptive, are one way that species may respond in situ to local environmental change. because cranial morphology is influenced by selective pressures arising ... | 2016 | 26511596 |
| 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 ... | 2016 | 27245290 |
| permeability of roads to movement of scrubland lizards and small mammals. | a primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. many small animal species focus their activities to particular microhabitats within their larger habitat. we sought to assess how different types of roads affect the movement of small vertebrates and to explore whether responses to ro ... | 2013 | 23772966 |
| apparent competition with an invasive plant hastens the extinction of an endangered lupine. | invasive plants may compete with native plants by increasing the pressure of native consumers, a mechanism known as "apparent competition." apparent competition can be as strong as or stronger than direct competition, but the role of apparent competition has rarely been examined in biological invasions. we used four years of demographic data and seed-removal experiments to determine if introduced grasses caused elevated levels of seed consumption on native plant species in a coastal dune system ... | 2010 | 20836448 |
| 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 ... | 2015 | 25679785 |
| fecal shedding of zoonotic food-borne pathogens by wild rodents in a major agricultural region of the central california coast. | recent outbreaks of food-borne illness associated with the consumption of produce have increased concern over wildlife reservoirs of food-borne pathogens. wild rodents are ubiquitous, and those living close to agricultural farms may pose a food safety risk should they shed zoonotic microorganisms in their feces near or on agricultural commodities. fecal samples from wild rodents trapped on 13 agricultural farms (9 produce, 3 cow-calf operations, and 1 beef cattle feedlot) in monterey and san ben ... | 2013 | 23934490 |
| 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 ... | 2012 | 22607076 |
| modeling susceptible infective recovered dynamics and plague persistence in california rodent-flea communities. | plague persists as an enzootic in several very different rodent-flea communities around the world. in california, a diversity of rodent-flea communities maintains the disease, and a single-host reservoir seems unlikely. logistic regression of plague presence on climate and topographic variables predicts plague in many localities where it is absent. thus, a dynamic community-based analysis was needed. deterministic susceptible infective recovered (sir) models were adapted for plague and analyzed ... | 2010 | 20158333 |