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The features of severe ischemic brain damage after strangulation by the owner of a 1-year-old German shepherd dog are described. The dog was disciplined by the owner during training by holding the dog off the ground by his choke chain collar. At first, the dog behaved normally, but he became increasingly ataxic and started circling to the left and showed reduced consciousness. The neurological examination revealed severe disorientation, left lateral pleurothotonus, and circling. The neurological findings were consistent with a multifocal brain lesion. A magnetic resonance imaging scan was performed and showed changes in the T2- and diffusion-weighted images, consistent with severe cerebral edema resulting from ischemia. Because of the severity of the clinical features, the dog was later euthanized. To the author's knowledge, this is the first report of a severe brain ischemia after strangulation in a dog.  相似文献   
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When conservation tillage is practised in agriculture, plant residues remain on the soil surface for soil protection purposes. These residues should be widely decomposed within the following vegetation period as microbial plant pathogens surviving on plant litter may endanger the currently cultivated crop. Important soil-borne fungal pathogens that preferably infect small grain cereals belong to the genus Fusarium. These pathogens produce the mycotoxin deoxynivalenol (DON), a cytotoxic agent, in infected cereal organs. This toxin frequently occurs in cereal residues like straw. So far it is unclear if DON degradation is affected by members of the soil food web within decomposing processes in the soil system. For this purpose, a microcosm study was conducted under controlled laboratory conditions to investigate the degradation activity of the earthworm species Lumbricus terrestris when exposed to Fusarium-infected wheat straw being contaminated with DON.Highly Fusarium-infected and DON-contaminated straw seemed to be more attractive to L. terrestris because it was incorporated faster into the soil compared with straw infected and contaminated at low levels. This is supported by a greater body weight gain (exposure time 5 weeks) and smaller body weight loss (exposure time 11 weeks) of L. terrestris, respectively, when highly contaminated straw was offered for different time periods.Furthermore, L. terrestris takes part in the efficient degradation of both Fusarium biomass and DON occurring in straw in close interaction with soil microorganisms. Consequently, earthworm activity contributes to the elimination of potentially infectious plant material from the soil surface.  相似文献   
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Disease has become an increasingly important issue for wildlife management over the past two decades. Adequate surveillance is fundamental for disease prevention and control, thus there is an increasing need for diagnostic assays for wildlife management. The objective of this study was to evaluate the performance of a field-portable biosensor adapted for rapid detection of specific antibodies in tortoise plasma that reflect a history of exposure to Mycoplasma agassizii, which is an agent of tortoise upper respiratory tract disease. Banked plasma samples were tested in two blinded trials, and the parameters that define the reliability of a diagnostic test were estimated based on externally validated tortoise plasma controls. The mean sensitivity of the biosensor (ability to identify exposed tortoises in the group of all exposed individuals) was 78%; the mean specificity (unexposed individuals with negative test result, out of all unexposed individuals tested) was 73%; the mean positive predictive value (exposed individuals with positive test, out of all individuals with positive test) was 82%; the mean negative predictive value (unexposed individuals with negative test, out of all individuals with negative test) was 68%. In a 15-min field-portable format, the biosensor was able to discriminate between true seropositive (n=34) and true seronegative (n=23) tortoise plasma with overall accuracy of 84%. The goals established for the tortoise population can help managers decide whether potential diagnostic errors should impact management decision-making, and whether the benefits of the field-portable format of the biosensor assay outweigh any potential disadvantages.  相似文献   
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In order to generate data on the cattle population and farm management in the state of Lower Saxony, Germany, a basic demographic survey was conducted. Afterwards these BSE-free farms as a reference population were compared with the population on BSE farms to identify risk factors for BSE infections. A variety of risk factors for BSE were reviewed, including the import of cattle from the United Kingdom, commercial foodstuff, dairy farming, herd size and cross-contamination with foodstuff for other farm animals. For the basic demographic survey of the reference, a questionnaire was mailed to a representative sample of cattle farms in Lower Saxony where BSE cattle had not occurred before the sample was taken. Distribution of risk factors within this reference population (n=731) and the BSE population (n=49) were compared following the concept of indirect standardisation in stratified populations. The size of farms was used as the stratification variable, with three strata. Under the same rate as in the reference population, the portion of Red Holstein cattle breed was four fold higher than in the BSE population (SER=4.03; p=0.0003). Milk replacer was fed 1.41 times more often on BSE farms (p=0.0478). However, the use of concentrated foodstuff for pigs (SER=0.21) was significantly less frequent in the BSE population than expected (p=0.0001), whereas the husbandry of sheep, goats or game animals seemed to increase the risk of BSE 2.85 times (p=0.0413). There were no significant differences between the two populations concerning the purchase of cattle (p=0.1514) and the use of concentrated feed for calves during the 1990s (p=0.6212). This is an epidemiological indication of increased susceptibility of Red Holstein cattle to BSE. However, this study did not confirm the assumption that the use of commercial foodstuff other than milk replacer or the purchase of cattle increases the risk of BSE infection. It nevertheless remains likely that commercial foodstuffs such as concentrated feed for calves were risk factors in Germany as well.  相似文献   
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Ultrasonographic evaluation of the spine, especially of the spinal cord, has been rarely reported in dogs. The atlanto-occipital junction provides a small acoustic window through which examination of the craniocervical transition can be performed. Normal sonographic findings of this region in 10 normal brachycephalic dogs are presented and compared with sonographic findings from 25 Cavalier King Charles Spaniels with the caudal occipital malformation syndrome. Sonographic findings were compared with magnetic resonance imaging findings to determine the extent of cerebellar herniation and syringohydromyelia. Cerebellar displacement into the foramen magnum was clearly identified sonographically; however, syringohydromyelia was not discernable due to bone overlay.  相似文献   
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