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Background

Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.

Methods

A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgdorferi sensu lato and A. phagocytophilum by the use of the SNAP®4DX ® ELISA test.

Results

Overall, 29.0% of the horses were seropositive for B. burgdorferi sensu lato whereas 22.3% were seropositive for A. phagocytophilum.

Conclusions

Antibodies against B burgdorferi sensu lato and A. phagocytophilum are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.
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Abstract: Despite its importance for wildlife, most forests in the Pacific Northwest contain low volumes of large downed wood compared to fine woody debris (FWD). We used a replicated experiment to compare short-term responses of deer mice (Peromyscus maniculatus) and western red-backed voles (Clethrionomys californicus) among 3 arrangements of FWD: piled, lopped and scattered, and pile burning, a commonly used method of fuel reduction in commercial Douglas fir (Pseudotsuga menziesii) forests in southwest Oregon, USA. We assessed habitat use, density, and survival of mice and voles during 2 consecutive summers (Jun—Aug 1999 and 2000). Both mice and voles used FWD cover disproportionately from its availability, and they differed in their responses to specific FWD arrangements. Mice used piled FWD (proportional use = 37.0%, 90% CI = 33.0–44.0) 43% more than expected (26.0). Number of mice captured (x̄ = 1.9 mice, 90% CI = 1.5–2.5) and index of home range size (x̄ = 4.8 m, 90% CI = 0.7–8.9) at individual FWD piles decreased up to 16% and increased up to 50%, respectively, for each 1-m increase in distance from piles. Voles used all FWD cover classes in proportion to availability, but number of voles captured increased slightly (x̄ = 0.016 voles/m, 90% CI = 0.001–0.031) for each 1-m increase in distance from piles. Piled FWD had no discernable effect on population density and apparent survival of mice, but analyses had low power (0.25, 0.67). Our results suggest that piling FWD would benefit deer mice, whereas lopped and scattered FWD might benefit voles. Thus, a combination of methods to reduce fire risk should be considered to accommodate multiple small mammal species. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):625–632; 2008)  相似文献   
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Although Georgia is known for its wines, industrial production of beer far outstrips industrial wine production for local markets: wine consumption occurs in ritual contexts in which new wine, typically purchased from peasant producers, is preferred; bottled, aged wines are primarily for exports. Beer, therefore, is a key area in which industrial production for indigenous consumers has been elaborated. Such goods are packaged and presented as being both ecologically "pure" and following "traditional" methods, often referencing "ethnographic" materials about traditional life in brand images, even as they proclaim their reliance on Western technologies.  相似文献   
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Carbohydrate and Amino Acid Analyses of Giardia muris Cysts   总被引:1,自引:0,他引:1  
ABSTRACT. Intact Giardia muris cysts were subjected to consecutive chloroform/methanol and 2% sodium dodecyl sulfate (SDS) extractions, and to amyloglucosidase treatment. The SDS-insoluble, amyloglucosidase-fast cyst walls (ACW) were further incubated with chymotrypsin, trypsin, papain, or pronase. Low voltage scanning electron microscopy revealed no discernible change in the ultrastructure of the filamentous layer of the cyst wall following any of these treatments. Affinity for cyst wall-specific monoclonal antibody (Meridian Diagnostics, Cincinnati. OH) was also retained after all treatments. Periodic acid-Schiff staining and gas chromatography/mass spectrometry (GC/MS) of intact and treated cyst hydrolysates showed a significant reduction in the amount of glucose associated with the cyst (72 nmoles/106 intact cysts vs 1.9 nmoles/106 ACW) as a result of amyloglucosidase treatment, indicating that glucose is stored with in Giardia as an SDS-insoluble polymer, Galactosamine was identified by GC/MS as the predominant sugar associated with both the ACW and the proteinase treated ACW (42 nmoles/106 ACW). High performance liquid chromatographic analysis of amino acids from intact and treated cyst hydrolysates revealed a marked reduction, but not elimination, of detectable quantities of identifiable amino acid residues (255 nmoles/106 intact cysts vs 6.8 nmoles/106 proteinase treated ACW). These results suggest that the filamentous layer of the cyst wall is primarily a carbohydrate peptide complex.  相似文献   
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Some of the assumptions underlying estimates of DNA and protein sequence divergence are examined. A solution for the variance of these estimates that allows for different mutation rates and different population sizes in each species and for an arbitrary structure in the initial population is obtained. It is shown that these conditions do not strongly affect estimates of divergence. In general, they cause the variance of divergence to be smaller than a binomial variance. Thus, the binomial variance that is usually assumed for these estimates is safely conservative. It is shown that variability in the mutation rate among sites can have an effect as large as or larger than variability in the mutation rate among bases. Variability in the mutation rate among bases and among sites causes the number of substitutions between two sequences to be underestimated. Protein and DNA sequences from several species are collected to estimate the variability in mutation rates among sites. When many homologous sequences are known, standard methods to estimate this variability can be used. The estimates of this variability show that this factor is important when considering the spectrum of spontaneous mutations and is strongly reflected in the divergence of sequences. Smaller variability is found for the third position of codons than for the first and second codon positions. This may be because of less selective constraints on this position or because the third position has been saturated with mutations for the sequences examined.   相似文献   
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The phylogeny of the Rhinocerotoidea (Mammalia, Perissodactyla)   总被引:3,自引:0,他引:3  
A new phylogeny of the Superfamily Rhinocerotoidea is proposed, based upon an analysis of shared derived characters of the skull, teeth and skeleton. Hyrachyus is considered the primitive sister-taxon of the three rhinocerotoid families (Amynodontidae, Hyracodontidae, Rhinocerotidae), and the amynodonts appear to be the sister-group of hyracodonts and rhinocerotids. The relationships of primitive hyracodonts and rhinocerotids are clarified. Menoceras and Pleuroceras (new Subfamily Menoceratinae) are removed from the Diceratheriinae, since they appear to be more closely related to higher rhinoceroses than they are to Diceratherium. Of the three major monophyletic groups of higher rhinocerotids (aceratherines, teleoceratines and rhinocerotines), the last two groups are more closely related to each other than either is to aceratherines. Toxotherium and Schizotheroides are tentatively removed from the Rhinocerotoidea and placed in the Lophiodontidae.  相似文献   
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