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31.
Kristin Nerlich Frieder Seidl Klaus Mastel Simone Graeff-H?nninger Wilhelm Claupein 《Gesunde Pflanzen》2012,64(3):129-139
The increasing cultivation of energy crops in the last few years may have an impact on changes in the environment, biodiversity and the landscape. Due to a longer rest of soil and reduced application of pesticides, perennial crops such as short rotation coppice (SRC) offer benefits that can have a positive effect on the biodiversity. However, to assess the overall impact of SRC on biodiversity, information on the quality of SRC as a habitat for animals and plants, depending on the woody species over several years and the management is required. In the years 2010 and 2011, the diversity of ground beetles of willow and poplar in SRC were examined using pitfall traps at three sites in southwestern Germany. It was distinguished between species, variety and age of the SRC. At all sites ground beetle diversity was significantly higher in the studied poplar stands than in those of the willows. In addition, significant differences between the varieties could be observed depending on the location and the year of examination. The older stands of the SRC showed in general a higher level of diversity. Due to the different variety preference of ground beetles it is recommended to plant a mixture of varieties. Furthermore, SRC of different ages should be established side by side, as with increasing tree age species of the open area decrease and forest species settle. Overall, SRC offer the potential to increase biodiversity in natural landscapes. 相似文献
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Purpose To describe six cases of conjunctivitis and ulcerative keratitis secondary to plant foreign bodies from weed‐contaminated grass hay which were lodged within the temporal conjunctival fornix in a herd of alpacas. Methods A total of 21 alpacas from the same farm developed blepharospasm and mucopurulent ocular discharge. Six of the 21 were evaluated at the University of Tennessee College of Veterinary Medicine within a 2‐week period. The six animals evaluated received an ophthalmic examination including slit‐lamp biomicroscopy, fluorescein staining, and topical corneal anesthesia for foreign body removal when necessary. Results Six animals had conjunctivitis characterized by hyperemia and mucopurulent discharge. Five animals had superficial ulcerative keratitis with intense corneal neovascularization and edema. In all cases, the keratitis was located at the temporal limbus. Seven plant foreign bodies were observed and were removed following topical corneal anesthesia in five animals. The plant seeds were identified as three common weed species found in orchard grass hay. Complete resolution of all clinical signs was achieved with foreign body removal and medical therapy. Conclusions Fan‐shaped temporal corneal ulcers may signify the presence of conjunctival foreign bodies in alpacas. Plant foreign bodies should be considered in addition to ocular infection when multiple animals of a herd are affected as outbreaks may occur with weed‐contaminated hay. 相似文献
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Characterization of Toxoplasma gondii genotypes in hosts living in remote, isolated regions is important for elucidating the population structure and transmission mode of this parasite. Herein, we report the results of direct genotyping of T. gondii in brain tissue of arctic foxes (Vulpes lagopus) from the remote, virtually cat-free, high arctic islands of Svalbard. DNA extracts from brains of 167 seropositive arctic foxes (including four cases of fatal toxoplasmosis) and 11 seronegative arctic foxes were genotyped at 10 loci (SAG1, SAG2, SAG3, BTUB, GRA6, L358, c22-8, c29-2, PK1, and Apico) using the polymerase chain reaction-restriction fragment length polymorphism method. Of the 167 samples from seropositive foxes (including toxoplasmosis cases), 31 were genotyped at all 10 loci and 24 were genotyped at four to nine loci. To ensure confidence in T. gondii strain genotyping, samples for which less than four loci were genotyped were not considered positive. None of the 11 samples from seronegative foxes was positive for the 10 markers. Of the 55 samples that genotyped positively, 46 were of the Type II strain, 7 were of the Type III strain, and 2 were of atypical T. gondii strains. Five representative samples of the three genotypes were sequenced at loci SAG2, SAG3, GRA6, PK1, and UPRT-1. The DNA sequences confirmed the genotyping results. This study shows that the archetype Type II T. gondii strain, which is most widely distributed in North America and Europe, also predominates in arctic foxes on the Svalbard archipelago. This suggests that the T. gondii at this location originate from continental Europe and that transmission may be mediated by migrating birds. This study highlights the significance of long-distance transport of T. gondii and demonstrates that high-resolution genotyping protocols are useful for direct genetic studies of T. gondii when isolation of live parasites is infeasible. 相似文献
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Riegel CM Stockham SL Patton KM Thomas CL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(3):353-356
Pleural effusion was examined from a 5-year-old, female Brittany Spaniel with a 7-day history of dyspnea, anorexia, and diarrhea. The fluid was yellow, cloudy, and slightly gelatinous, and had a total protein concentration of 2.8 g/dL, a total nucleated cell concentration of 1.1 x 10(3)/muL, and a triglyceride concentration of 177 mg/dL. A cytocentrifuged preparation contained a mixed inflammatory cell population with a predominance of small lymphocytes and abundant mucinous material in the background. The dog died 3 days later and a mass was found within the lumen and wall of the right auricle of the heart at necropsy. Histopathologic sections of the mass contained a population of anaplastic spindle cells diffusely suspended in a pale basophilic matrix, consistent with myxosarcoma. The cells were positive for vimentin and negative for cytokeratin, desmin, and von Willebrand factor VIII-related antigen. A myxoid matrix was confirmed by positive staining with Alcian blue. Myxosarcoma is a rare cardiac tumor in dogs that should be considered, along with mucus-producing carcinomas and bile, as a cause of muculent effusion. 相似文献
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Mark D Bennett Lucy Woolford Philip K Nicholls Kristin S Warren Amanda J O'Hara 《Journal of veterinary diagnostic investigation》2008,20(3):376-379
The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species. Routine histology of liver samples collected at necropsy from 19 of 20 (95%) western barred bandicoots revealed the sporadic to common occurrence of abnormal hepatocyte nuclei characterized by margination of chromatin and concomitant central pallor. Some abnormal hepatocyte nuclei were mildly to markedly enlarged and irregularly shaped. Periodic acid-Schiff reagent stained 131 of 142 (92%) of these abnormal hepatocyte nuclei. Positive staining was completely eliminated by diastase pretreatment. Transmission electron microscopy revealed that abnormal hepatocyte nuclei with marginated chromatin did not contain viral particles. Rather, glycogen beta-particles and alpha-rosettes were identified within some abnormal hepatocyte nuclei. Glycogen intranuclear inclusions were an incidental finding in western barred bandicoot hepatocytes. 相似文献
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Mats Söderström Gustav Sohlenius Lars Rodhe Kristin Piikki 《Precision Agriculture》2016,17(5):588-607
In the initial phase of a national project to map clay, sand and soil organic matter (SOM) content in arable topsoil in Sweden, a study area in south-west Sweden comprising about 100 000 ha of arable land was assessed. Models were created for texture, SOM and two estimated variables for lime requirement determination (target pH and buffering capacity), using a data mining method (multivariate adaptive regression splines). Two existing reference soil datasets were used: a grid dataset and a dataset created for individual farms. The predictor data were of three types: airborne gamma-ray spectrometry data, digital elevation from airborne laser scanning, and legacy data on Quaternary geology. Validations were designed to suit applicability assessments of prediction maps for precision agriculture. The predictor data proved applicable for regional mapping of topsoil texture at 50 × 50 m2 spatial resolution (root mean square error: clay = 6.5 %; sand = 13.2 %). A novel modelling strategy, ‘Farm Interactive’, in which soil analysis data for individual farms were added to the regional data, and given extra weight, improved the map locally. SOM models were less satisfactory. Variable-rate application files for liming created from derived digital soil maps and locally interpolated soil data were compared with ‘ground truth’ maps created by proximal sensors on one test farm. The Farm Interactive methodology generated the best predictions and was deemed suitable for adaptation of regional digital soil maps for precision agricultural purposes. 相似文献