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1.
Borrelia burgdorferi and Anaplasma phagocytophilum are obligate intracellular parasites that maintain their life cycles in enzoonotic vector‐host cycles with Ixodes scapularis as a vector. In addition to ticks, the hosts are commonly infested with insects from the Hippoboscidae family. This study confirms the presence of B. burgdorferi and A. phagocytophilum in deer keds (Lipoptena cervi) removed from white‐tailed deer using PCR. Detection of these pathogens in deer ked represents a potential novel susceptibility of wildlife and also suggests the risk of transmission of these pathogens to humans and animals alike through the bite of an infected ectoparasite. This study represents the first instance in the U.S. of detection of tick‐borne pathogens in a member of the Hippoboscid family.  相似文献   

2.
Changes in land use patterns and vegetation can trigger ecological change in occupancy and community composition. Among the potential ecological consequences of land use change is altered susceptibility to occupancy by invasive species. We investigated the responses of three introduced mammals (red deer, Cervus elaphus; wild boar, Sus scrofa; and European hare, Lepus europaeus) to replacement of native vegetation by exotic pine plantations in the Patagonian forest‐steppe ecotone using camera‐trap surveys (8633 trap‐days). We used logistic regression models to relate species presence with habitat variables at stand and landscape scales. Red deer and wild boar used pine plantations significantly more frequently than native vegetation. In contrast, occurrence of European hares did not differ between pine plantations and native vegetation, although hares were recorded more frequently in firebreaks than in plantations or native vegetation. Presence of red deer and wild boar was positively associated with cover of pine plantations at the landscape scale, and negatively associated with mid‐storey cover and diversity at the stand scale. European hares preferred sites with low arboreal and mid‐storey cover. Our results suggest that pine plantations promote increased abundances of invasive species whose original distributions are associated with woodlands (red deer and wild boar), and could act as source or pathways for invasive species to new areas.  相似文献   

3.
Himalayan musk deer (Moschus leucogaster; hereafter musk deer) are endangered as a result of poaching and habitat loss. The species is nocturnal, crepuscular, and elusive, making direct observation of habitat use and behavior difficult. However, musk deer establish and repeatedly use the same latrines for defecation. To quantify musk deer habitat correlates, we used observational spatial data based on presence–absence of musk deer latrines, as well as a range of fine spatial‐scale ecological covariates. To determine presence–absence of musk deer, we exhaustively searched randomly selected forest trails using a 20‐m belt transect in different study sites within the Neshyang Valley in the Annapurna Conservation Area. In a subsequent way, study sites were classified as habitat or nonhabitat for musk deer. A total of 252 plots, 20 × 20 m, were systematically established every 100 m along 51 transects (each ~0.5 km long) laid out at different elevations to record a range of ecological habitat variables. We used mixed‐effect models and principal component analysis to characterize relationships between deer presence–absence data and habitat variables. We confirmed musk deer use latrines in forests located at higher elevations (3,200–4,200 m) throughout multiple seasons and years. Himalayan birch (Betula utilis) dominated forest, mixed Himalayan fir (Abies spectabilis), and birch forest were preferred over pure Himalayan fir and blue pine (Pinus wallichiana) forest. Greater crown cover and shrub diversity were associated with the presence of musk deer whereas tree height, diameter, and diversity were weakly correlated. Topographical attributes including aspect, elevation, distance to water source, and slope were also discriminated by musk deer. Over‐ and understory forest management can be used to protect forests likely to have musk deer as predicted by the models to ensure long‐term conservation of this rare deer.  相似文献   

4.
Fucosylated structures participate in a wide range of pathological processes in eukaryotes and prokaryotes. The impact of fucose on microbial pathogenesis, however, has been less appreciated in arthropods of medical relevance. Thus, we used the tick‐borne bacterium Anaplasma phagocytophilum– the agent of human granulocytic anaplasmosis to understand these processes. Here we show that A. phagocytophilum uses α1,3‐fucose to colonize ticks. We demonstrate that A. phagocytophilum modulates the expression of α1,3‐fucosyltransferases and gene silencing significantly reduces colonization of tick cells. Acquisition but not transmission of A. phagocytophilum was affected when α1,3‐fucosyltransferases were silenced during tick feeding. Our results uncover a novel mechanism of pathogen colonization in arthropods. Decoding mechanisms of pathogen invasion in ticks might expedite the development of new strategies to interfere with the life cycle of A. phagocytophilum.  相似文献   

5.
Quantifying the relative influence of multiple mechanisms driving recent range expansion of non‐native species is essential for predicting future changes and for informing adaptation and management plans to protect native species. White‐tailed deer (Odocoileus virginianus) have been expanding their range into the North American boreal forest over the last half of the 20th century. This has already altered predator–prey dynamics in Alberta, Canada, where the distribution likely reaches the northern extent of its continuous range. Although current white‐tailed deer distribution is explained by both climate and human land use, the influence each factor had on the observed range expansion would depend on the spatial and temporal pattern of these changes. Our objective was to quantify the relative importance of land use and climate change as drivers of white‐tailed deer range expansion and to predict decadal changes in white‐tailed deer distribution in northern Alberta for the first half of the 21st century. An existing species distribution model was used to predict past decadal distributions of white‐tailed deer which were validated using independent data. The effects of climate and land use change were isolated by comparing predictions under theoretical “no‐change between decades” scenarios, for each factor, to predictions under observed climate and land use change. Climate changes led to more than 88%, by area, of the increases in probability of white‐tailed deer presence across all decades. The distribution is predicted to extend 100 km further north across the northeastern Alberta boreal forest as climate continues to change over the first half of the 21st century.  相似文献   

6.
The relationship between climate data and tick questing activity is crucial for estimation of the spatial and temporal distribution of the risk of ticks and tick‐borne diseases. This study establishes correlations between selected meteorological variables provided by the Weather Research and Forecasting model (WRF) and the questing activity of Ixodes ricinus nymphs and adults on a regional scale across Lower Silesia, Poland. Application of Generalized Linear Mixed Models (GLMM), built separately for adults and nymphs, showed that solar radiation, air temperature, and saturation deficit appeared to be the meteorological variables of prime importance, whereas the wind speed was less important. However, the effect of meteorological parameters was different for adults and nymphs. The adults are also more influenced by forest cover and the percentage of forest type if compared to nymphs. The WRF model providing meteorological variables separately for each location and day of tick sampling can be useful in studies of questing activity of ticks on a regional scale.  相似文献   

7.
Aim Models relating species distributions to climate or habitat are widely used to predict the effects of global change on biodiversity. Most such approaches assume that climate governs coarse‐scale species ranges, whereas habitat limits fine‐scale distributions. We tested the influence of topoclimate and land cover on butterfly distributions and abundance in a mountain range, where climate may vary as markedly at a fine scale as land cover. Location Sierra de Guadarrama (Spain, southern Europe) Methods We sampled the butterfly fauna of 180 locations (89 in 2004, 91 in 2005) in a 10,800 km2 region, and derived generalized linear models (GLMs) for species occurrence and abundance based on topoclimatic (elevation and insolation) or habitat (land cover, geology and hydrology) variables sampled at 100‐m resolution using GIS. Models for each year were tested against independent data from the alternate year, using the area under the receiver operating characteristic curve (AUC) (distribution) or Spearman's rank correlation coefficient (rs) (abundance). Results In independent model tests, 74% of occurrence models achieved AUCs of > 0.7, and 85% of abundance models were significantly related to observed abundance. Topoclimatic models outperformed models based purely on land cover in 72% of occurrence models and 66% of abundance models. Including both types of variables often explained most variation in model calibration, but did not significantly improve model cross‐validation relative to topoclimatic models. Hierarchical partitioning analysis confirmed the overriding effect of topoclimatic factors on species distributions, with the exception of several species for which the importance of land cover was confirmed. Main conclusions Topoclimatic factors may dominate fine‐resolution species distributions in mountain ranges where climate conditions vary markedly over short distances and large areas of natural habitat remain. Climate change is likely to be a key driver of species distributions in such systems and could have important effects on biodiversity. However, continued habitat protection may be vital to facilitate range shifts in response to climate change.  相似文献   

8.
Loss, fragmentation and decreasing quality of habitats have been proposed as major threats to biodiversity world‐wide, but relatively little is known about biodiversity responses to multiple pressures, particularly at very large spatial scales. We evaluated the relative contributions of four landscape variables (habitat cover, diversity, fragmentation and productivity) in determining different components of avian diversity across Europe. We sampled breeding birds in multiple 1‐km2 landscapes, from high forest cover to intensive agricultural land, in eight countries during 2001?2002. We predicted that the total diversity would peak at intermediate levels of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; forest and open‐habitat specialists would show threshold conditions along gradients of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; resident species would be more strongly impacted by forest cover and fragmentation than migratory species; and generalists and urban species would show weak responses. Measures of total diversity did not peak at intermediate levels of forest cover or fragmentation. Rarefaction‐standardized species richness decreased marginally and linearly with increasing forest cover and increased non‐linearly with productivity, whereas all measures increased linearly with increasing fragmentation and landscape diversity. Forest and open‐habitat specialists responded approximately linearly to forest cover and also weakly to habitat diversity, fragmentation and productivity. Generalists and urban species responded weakly to the landscape variables, but some groups responded non‐linearly to productivity and marginally to habitat diversity. Resident species were not consistently more sensitive than migratory species to any of the landscape variables. These findings are relevant to landscapes with relatively long histories of human land‐use, and they highlight that habitat loss, fragmentation and habitat‐type diversity must all be considered in land‐use planning and landscape modeling of avian communities.  相似文献   

9.
Aim Climate change has the potential to have an impact on the distribution of ticks and tick‐borne diseases. This paper identifies the changes in climate suitability for the tick Rhipicephalus (Boophilus) microplus in the Americas by analysing climate data for the period 1950–99. Location The model was applied to the American continent. Methods A model based on Environmental Niche Modelling was used on a gridded (0.5°) long‐term (1950–99) climate data set. A map of the core range of the species was constructed, and areas where habitat suitability (HS) changes suddenly over short time periods were identified as regions of high sensitivity. Tendency of climate in the continent was evaluated and scenarios constructed for 2025 and 2050. Results Regions of high sensitivity included the southern USA, Mexico and western and central Argentina. Analysis of climate variables in these regions identified water vapour pressure deficit and evaporation as underlying the high sensitivity of habitat suitability in the USA and Mexico, and showed that episodes of high variability are linked to the El Niño Southern Oscillation. Projections of the tendency of HS as observed for the 1950–99 period point to an increase in this value in parts of the southern USA and in central Argentina, a finding that can be attributed to the progressive increase in minimum and yearly averaged temperatures. Conclusions Short‐term changes in climate may drive the system into unstable situations with sudden changes in habitat suitability for the target tick in specific zones of the Americas. Results suggest an increased abiotic (climate) suitability for R. microplus in areas whose habitat is currently unsuitable for this species.  相似文献   

10.
Ongoing climate change and land‐use change have the potential to substantially alter the distribution of large herbivores. This may result in drastic changes in ecosystems by changing plant–herbivore interactions. Here, we developed a model explaining sika deer persistence and colonization between 25 years in terms of neighborhood occupancy and habitat suitability. We used climatic, land‐use, and topographic variables to calculate the habitat suitability and evaluated the contributions of the variables to past range changes of sika deer. We used this model to predict the changes in the range of sika deer over the next 100 years under four scenario groups with the combination of land‐use change and climate change. Our results showed that both climate change and land‐use change had affected the range of sika deer in the past 25 years. Habitat suitability increased in northern or mountainous regions, which account for 71.6% of Japan, in line with a decrease in the snow cover period. Habitat suitability decreased in suburban areas, which account for 28.4% of Japan, corresponding to land‐use changes related to urbanization. In the next 100 years, the decrease in snow cover period and the increase in land abandonment were predicted to accelerate the range expansion of sika deer. Comparison of these two driving factors revealed that climate change will contribute more to range expansion, particularly from the 2070s onward. In scenarios that assumed the influence of both climate change and land‐use change, the total sika deer range increased by between +4.6% and +11.9% from the baseline scenario. Climate change and land‐use change will require additional efforts for future management of sika deer, particularly in the long term.  相似文献   

11.
Aim We examined relationships between breeding bird distribution of 10 forest songbirds in the Great Lakes Basin, large‐scale climate and the distribution of land cover types as estimated by advanced very high resolution radiometer (AVHRR) and multi‐spectral scanner (MSS) land cover classifications. Our objective was to examine the ability of regional climate, AVHRR (1 km resolution) land cover and MSS (200 m resolution) land cover to predict the distribution of breeding forest birds at the scale of the Great Lakes Basin and at the resolution of Breeding Bird Atlas data (5–10 km2). Specifically we addressed the following questions. (1) How well do AVHRR or MSS classifications capture the variation in distribution of bird species? (2) Is one land cover classification more useful than the other for predicting distribution? (3) How do models based on climate compare with models based on land cover? (4) Can the combination of both climate and land cover improve the predictive ability of these models. Location Modelling was conducted over the area of the Great Lakes Basin including parts of Ontario, Canada and parts of Illinois, Indiana, Michigan, New York, Ohio, Pennsylvania Wisconsin, and Minnesota, USA. Methods We conducted single variable logistic regression with the forest classes of AVHRR and MSS land cover using evidence of breeding as the response variable. We conducted multiple logistic regression with stepwise selection to select models from five sets of explanatory variables (AVHRR, MSS, climate, AVHRR + climate, MSS + climate). Results Generally, species were related to both AVHRR and MSS land cover types in the direction expected based on the known local habitat use of the species. Neither land cover classification appeared to produce consistently more intuitive results. Good models were generated using each of the explanatory data sets examined here. And at least one but usually all five variable sets produced acceptable or excellent models for each species. Main conclusions Both climate and large scale land cover were effective predictors of the distribution of the 10 forest bird species examined here. Models generated from these data had good classification accuracy of independent validation data. Good models were produced from all explanatory data sets or combinations suggesting that the distribution of climate, AVHRR land cover, and MSS land cover all captured similar variance in the distribution of the birds. It is difficult to separate the effects of climate and vegetation on the species’ distributions at this scale.  相似文献   

12.
Ehrlichia chaffeensis, transmitted from Amblyomma americanum ticks, causes human monocytic ehrlichiosis. It also infects white-tailed deer, dogs and several other vertebrates. Deer are its reservoir hosts, while humans and dogs are incidental hosts. E. chaffeensis protein expression is influenced by its growth in macrophages and tick cells. We report here infection progression in deer or dogs infected intravenously with macrophage- or tick cell-grown E. chaffeensis or by tick transmission in deer. Deer and dogs developed mild fever and persistent rickettsemia; the infection was detected more frequently in the blood of infected animals with macrophage inoculum compared to tick cell inoculum or tick transmission. Tick cell inoculum and tick transmission caused a drop in tick infection acquisition rates compared to infection rates in ticks fed on deer receiving macrophage inoculum. Independent of deer or dogs, IgG antibody response was higher in animals receiving macrophage inoculum against macrophage-derived Ehrlichia antigens, while it was significantly lower in the same animals against tick cell-derived Ehrlichia antigens. Deer infected with tick cell inoculum and tick transmission caused a higher antibody response to tick cell cultured bacterial antigens compared to the antibody response for macrophage cultured antigens for the same animals. The data demonstrate that the host cell-specific E. chaffeensis protein expression influences rickettsemia in a host and its acquisition by ticks. The data also reveal that tick cell-derived inoculum is similar to tick transmission with reduced rickettsemia, IgG response and tick acquisition of E. chaffeensis.  相似文献   

13.
Equine piroplasmosis (EP), caused by two parasitic organisms, Theileria equi and Babesia caballi, is a tick‐borne disease of recent concern in horses in the U.S.A. Outbreaks of EP have been detected in Florida, Missouri, Kansas and Texas. In 2009, EP transmission in Texas occurred through the adults of two tick species, Amblyomma mixtum [formerly known as Amblyomma cajennense (Fabricius, 1787)] Koch (Ixodida: Ixodidae) and Dermacentor variabilis (Say) (Ixodida: Ixodidae), the American dog tick (ADT). In this study, we developed a continent‐scale map for the distribution of the EP vector species D. variabilis, using a presence‐only modelling approach to assess the habitat preferences of this tick. We used identification records from our tick geodatabase of locations in which the presence of the ADT had been noted. The potential distribution of the ADT in the U.S.A. was estimated from environmental factors using the maximum entropy approach based on localities in which there is a high probability of occurrence according to habitat suitability. Elevation and temperature were found to be biologically significant environmental variables influencing the presence of this tick species. Properly designed and constructed probability surfaces using maximum entropy offer one useful approach to the mapping of distribution ranges of tick species based on suitable habitat in the U.S.A.  相似文献   

14.
Global patters of species distributions and their underlying mechanisms are a major question in ecology, and the need for multi‐scale analyses has been recognized. Previous studies recognized climate, topography, habitat heterogeneity and disturbance as important variables affecting such patterns. Here we report on analyses of species composition – environment relationships among different taxonomic groups in two continents, and the components of such relationships, in the contiguous USA and Australia. We used partial Canonical Correspondence Analysis of occurrence records of mammals and breeding birds from the Global Biodiversity Information Facility, to quantify relationships between species composition and environmental variables in remote geographic regions at multiple spatial scales, with extents ranging from 105 to 107 km2 and sampling grids from 10 to 10,000 km2. We evaluated the concept that two elements contribute to the impact of environmental variables on composition: the strength of species' affinity to an environmental variable, and the amount of variance in the variable. To disentangle these two elements, we analyzed correlations between resulting trends and the amount of variance contained in different environmental variables to isolate the mechanisms behind the observed relationships. We found that climate and land use‐land cover are responsible for most explained variance in species composition, regardless of scale, taxonomic group and geographic region. However, the amount of variance in species composition attributed to land use / land cover (LULC) was closely related to the amount of intrinsic variability in LULC in the USA, but not in Australia, while the effect of climate on species composition was negatively correlated to the variability found in the climatic variables. The low variance in climate, compared to LULC, suggests that species in both taxonomic groups have strong affinity to climate, thus it has a strong effect on species distribution and community composition, while the opposite is true for LULC.  相似文献   

15.
Reactive oxygen species (ROS) that are induced upon pathogen infection plays an important role in host defence. The rickettsial pathogen Anaplasma phagocytophilum, which is primarily transmitted by Ixodes scapularis ticks in the United States, has evolved many strategies to escape ROS and survive in mammalian cells. However, little is known on the role of ROS in A. phagocytophilum infection in ticks. Our results show that A. phagocytophilum and hemin induce activation of l ‐tryptophan pathway in tick cells. Xanthurenic acid (XA), a tryptophan metabolite, supports A. phagocytophilum growth in tick cells through inhibition of tryptophan dioxygenase (TDO) activity leading to reduced l ‐kynurenine levels that subsequently affects build‐up of ROS. However, hemin supports A. phagocytophilum growth in tick cells by inducing TDO activity leading to increased l ‐kynurenine levels and ROS production. Our data reveal that XA and kynurenic acid (KA) chelate hemin. Furthermore, treatment of tick cells with 3‐hydroxyl l ‐kynurenine limits A. phagocytophilum growth in tick cells. RNAi‐mediated knockdown of kynurenine aminotransferase expression results in increased ROS production and reduced A. phagocytophilum burden in tick cells. Collectively, these results suggest that l ‐tryptophan pathway metabolites influence A. phagocytophilum survival by affecting build up of ROS levels in tick cells.  相似文献   

16.
Anaplasma phagocytophilum causes human granulocytic anaplasmosis, one of the most common tick‐borne diseases in North America. This unusual obligate intracellular pathogen selectively persists within polymorphonuclear leucocytes. In this study, using the yeast surrogate model we identified an A. phagocytophilum virulence protein, AptA (A. phagocytophilum toxin A), that activates mammalian Erk1/2 mitogen‐activated protein kinase. This activation is important for A. phagocytophilum survival within human neutrophils. AptA interacts with the intermediate filament protein vimentin, which is essential for A. phagocytophilum‐induced Erk1/2 activation and infection. A. phagocytophilum infection reorganizes vimentin around the bacterial inclusion, thereby contributing to intracellular survival. These observations reveal a major role for the bacterial protein, AptA, and the host protein, vimentin, in the activation of Erk1/2 during A. phagocytophilum infection.  相似文献   

17.
HUW LLOYD 《Ibis》2008,150(4):735-745
Habitat restoration strategies for fragmented high Andean forest landscapes must consider the influence of within‐patch habitat quality on bird abundance. I examined vegetation and bird abundance at three locations within a highly fragmented Polylepis forest landscape in the Cordillera Vilcanota, southern Peru. Across the landscape, there was significant variation in the vegetation structure of Polylepis forest patches of different size categories, especially in terms of tree girth, tree height, tree density, and canopy vegetation structure. Principal Component Analysis extracted five factors of habitat quality, which together accounted for 74.2% of the variability within 15 habitat variables. Polylepis bird species differed in their responses to habitat quality but, overall, variation in Polylepis bird abundance was not fully captured by the range of habitat quality variables. Tall, dense vegetation cover was clearly important for 11 conservation‐important species, a high density of large trees was important for 10 species and primary forest ground cover was important for eight species. Habitat quality exhibited no significant influence on the abundance of only one species –Asthenes urubambensis. The abundance of seven species was associated with lower elevation forest, but only one species was associated with higher elevation forest. Management of habitat quality in large and medium remnant forest patches throughout the Cordillera Vilcanota, particularly in the 3800–4200 m elevation range, will be a cornerstone in ensuring the persistence of the majority of conservation‐important bird species populations.  相似文献   

18.
Aim We aimed to describe the large‐scale patterns in population density of roe deer Caprelous capreolus in Europe and to determine the factors shaping variation in their abundance. Location Europe. Methods We collated data on roe deer population density from 72 localities spanning 25° latitude and 48° longitude and analysed them in relation to a range of environmental factors: vegetation productivity (approximated by the fraction of photosynthetically active radiation) and forest cover as proxies for food supply, winter severity, summer drought and presence or absence of large predators (wolf, Canis lupus, and Eurasian lynx, Lynx lynx), hunter harvest and a competitor (red deer, Cervus elaphus). Results Roe deer abundance increased with the overall productivity of vegetation cover and with lower forest cover (sparser forest cover means that a higher proportion of overall plant productivity is allocated to ground vegetation and thus is available to roe deer). The effect of large predators was relatively weak in highly productive environments and in regions with mild climate, but increased markedly in regions with low vegetation productivity and harsh winters. Other potentially limiting factors (hunting, summer drought and competition with red deer) had no significant impact on roe deer abundance. Main conclusions The analyses revealed the combined effect of bottom‐up and top‐down control on roe deer: on a biogeographical scale, population abundance of roe deer has been shaped by food‐related factors and large predators, with additive effects of the two species of predators. The results have implications for management of roe deer populations in Europe. First, an increase in roe deer abundance can be expected as environmental productivity increases due to climate change. Secondly, recovery plans for large carnivores should take environmental productivity and winter severity into account when predicting their impact on prey.  相似文献   

19.
The greatest common threat to birds in Madagascar has historically been from anthropogenic deforestation. During recent decades, global climate change is now also regarded as a significant threat to biodiversity. This study uses Maximum Entropy species distribution modeling to explore how potential climate change could affect the distribution of 17 threatened forest endemic bird species, using a range of climate variables from the Hadley Center's HadCM3 climate change model, for IPCC scenario B2a, for 2050. We explore the importance of forest cover as a modeling variable and we test the use of pseudo‐presences drawn from extent of occurrence distributions. Inclusion of the forest cover variable improves the models and models derived from real‐presence data with forest layer are better predictors than those from pseudo‐presence data. Using real‐presence data, we analyzed the impacts of climate change on the distribution of nine species. We could not predict the impact of climate change on eight species because of low numbers of occurrences. All nine species were predicted to experience reductions in their total range areas, and their maximum modeled probabilities of occurrence. In general, species range and altitudinal contractions follow the reductive trend of the Maximum presence probability. Only two species (Tyto soumagnei and Newtonia fanovanae) are expected to expand their altitude range. These results indicate that future availability of suitable habitat at different elevations is likely to be critical for species persistence through climate change. Five species (Eutriorchis astur, Neodrepanis hypoxantha, Mesitornis unicolor, Euryceros prevostii, and Oriola bernieri) are probably the most vulnerable to climate change. Four of them (E. astur, M. unicolor, E. prevostii, and O. bernieri) were found vulnerable to the forest fragmentation during previous research. Combination of these two threats in the future could negatively affect these species in a drastic way. Climate change is expected to act differently on each species and it is important to incorporate complex ecological variables into species distribution models.  相似文献   

20.
The tick-transmitted Anaplasma phagocytophilum has been recorded in a range of mammal species and causes granulocytic ehrlichiosis in humans, horses, and companion animals as well as tick-borne fever in ruminants. Although deer and other ruminant species are known to be natural hosts, the distribution among sympatric deer populations is unexplored. Blood from 80 deer of four species were screened using an A. phagocytophilum-specific real-time polymerase chain reaction. Overall, 29% (19–40) of deer tested positive. Fallow deer (Dama dama), the most numerous species, had significantly lower prevalence (21%) than roe (Capreolus capreolus), red (Cervus elaphus), or sika (Cervus nippon) deer (average 50%). It is suggested that patterns of habitat use influence infection levels in different deer species. The role of deer as reservoirs of anaplasmosis remains unknown; however, prevalence in deer could be a useful index of local infection pressure and the risk of disease in domestic animals and humans.  相似文献   

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