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81.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus from Western,Northern, and Central Europe (2000–2014). Part 2: Prognostic assessment 下载免费PDF全文
Gaby van Galen DVM PhD DECEIM Joke Rijckaert DVM Tim Mair BVSc PhD DECEIM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Cornélie Westermann DVM PhD DECEIM Claude Saegerman DVM PhD DECVPH 《Journal of Veterinary Emergency and Critical Care》2017,27(6):697-706
82.
Jiří Skuhrovec Ondřej Douda Roman Pavela Pavel Klouček Matěj Božik Miloslav Zouhar 《American Journal of Potato Research》2017,94(1):64-69
The effect of essential oil (EO) from anise (Pimpinellia anisum) on the mortality of young larvae of Colorado potato beetles has been studied. In our bioassays, P. anisum EO significantly increased the mortality of the second instar larvae of L. decemlineata. Significantly different values of LD50 and LD90 were established for acute (LD50 = 1.76, and LD90 = 8.29) as well as chronic toxicity (LD50 = 0.45, and LD90 = 1.01). Decrease of both values over experimental period was evident, which showed that the larval mortality was slow and cumulative. The composition of EO used for biological experiments was also assessed. The main component detected in EO from P. anisum was anethole (79.87%), followed by anisaldehyde (7.74%), estragole (5.88%) and β-linalool (1.07%). Within five days, residual concentration of EO decreased from 3.87 mg/g of dry weight immediately after foliar applications to 0.9 mg per g of dry weight. The effect of this slow evaporation could be explained by dominant presence of anethole or by the type of formulation and the addition of oil and tween. Results of our study demonstrate that EO from P. anisum has insecticidal properties that may lead to the development of new organic products for the control of Colorado potato beetles. 相似文献
83.
Patterns,risk factors and characteristics of reported and perceived foot-and-mouth disease (FMD) in Uganda 总被引:1,自引:1,他引:0
Ayebazibwe Chrisostom Tjørnehøj Kirsten Mwiine Frank N. Muwanika Vincent B. Ademun Okurut Anna Rose Siegismund Hans R. Alexandersen Soren 《Tropical animal health and production》2010,42(7):1547-1559
Patterns of outbreaks of foot-and-mouth disease (FMD) in Uganda were elucidated from spatial and temporal retrospective data
retrieved from monthly reports from District Veterinary Officers (DVOs) to the central administration for the years spanning
2001–2008. An assessment of perceived FMD occurrence, risk factors and the associated characteristics was made based on semi-structured
questionnaires administered to the DVOs. During this period, a total of 311 FMD outbreaks were reported in 56 (70%) out of
Uganda’s 80 districts. The number of reported FMD outbreaks changed over time and by geographical regions. Occurrence of FMD
was significantly associated with the dry season months (p = 0.0346), the time when animals movements are more frequent. The average number of FMD outbreaks was higher for some sub-counties
adjacent to national parks than for other sub-counties, whilst proximity to international border only seemed to play a role
at the southern border. DVOs believed that the major risk factor for FMD outbreaks was animal movements (odds ratio OR 50.8,
confidence interval CI 17.8–144.6) and that most outbreaks were caused by introduction of sick animals. 相似文献
84.
5头健康雄性去势水牛(2~3岁、体重300~500kg),经粪便检查和Dot-ELISA检测确认无肝片吸虫感染。每头每天口服60个肝片吸虫囊蚴,连续20d,共感染1200个囊蚴,用以研究水牛慢性感染(少量多次感染)肝片吸虫对安替比林代谢动力学的影响。每周定时由颈静脉采血,测定血清酶水平变化。于感染前、感染后急性期及慢性期进行安替比林动力学试验。由颈静脉瘘管收集血样,用尿液收集器收集尿样,用HPLC法分析血浆安替比林动力学参数及尿安替比林清除率。结果表明:水牛慢性实验性感染肝片吸虫呈亚临床状态,AP的血浆及尿代谢物清除率在急性期分别下降了48%和61.91%,慢性期逐步恢复。 相似文献
85.
Nina Hj Christiansen Peter Srensen Rodrigo Labouriau Bent T. Christensen Gitte Holton Rubk 《植物养料与土壤学杂志》2020,183(4):416-428
Background: The fertilizer value of phosphorus (P) in waste products relies heavily on its availability to the subsequent crop. Aim: We studied the link between extractable P in waste products and apparent P recovery (APR, i.e., difference in plant P uptake between P amended and un‐amended soils divided by the amount of P added) using spring barley grown on three sandy soils. Methods: The products included sewage sludge, biomass ash, struvite, compost, meat and bone meal, biochar from sewage sludge, and industrial sludge. Soft rock phosphate and triple‐superphosphate (TSP) were included for comparison. Availability of P was characterized by extraction with water and solutions of sodium bicarbonate, citric acid, oxalic acid, hydrochloric acid, ammonium acetate, ammonium fluoride and anion exchange resin membranes. TSP was used to establish mineral‐fertilizer‐equivalents (MFE). Water and bicarbonate extractions were also applied to products incubated with soil before extraction. Results: The APR ranged 26 to 31% for TSP and 0 to 30% for waste products. APR correlated most strongly with bicarbonate extractable P. The correlation increased when products were incubated with soil before extraction. Conclusions: We conclude that bicarbonate extraction is a good indicator of potential P availability. However, interactions between waste products and soil properties modify P availability. 相似文献
86.
A. K. Bergjord Olsen T. Persson A. de Wit L. Nkurunziza E. Sindhøj H. Eckersten 《Journal of Agronomy and Crop Science》2018,204(1):62-73
Based on soil temperature, snow depth and the grown cultivar's maximum attainable level of frost tolerance (LT50c), the FROSTOL model simulates development of frost tolerance (LT50) and winter damage, thereby enabling risk calculations for winter wheat survival. To explore the accuracy of this model, four winter wheat cultivars were sown in a field experiment in Uppsala, Sweden in 2013 and 2014. The LT50 was determined by tests of frost tolerance in November, and the cultivars’ LT50c was estimated. Further, recorded winter survival from 20 winter wheat field variety trials in Sweden and Norway was collected from two winter seasons with substantial winter damages. FROSTOL simulations were run for selected cultivars at each location. According to percentage of winter damage, the cultivar survival was classified as “survived,” “intermediate” or “killed.” Mean correspondence between recorded and simulated class of winter survival was 75% and 37% for the locations in Sweden and Norway, respectively. Stress factors that were not accounted for in FROSTOL might explain the poorer accuracy at the Norwegian locations. The accuracy was poorest for cultivars with intermediate LT50c levels. When low temperature was the main cause of damage, as at the Swedish locations, the model accuracy was satisfying. 相似文献
87.
Influence of introduced potential biocontrol agents on maize seedling growth and bacterial community structure in the rhizosphere 总被引:1,自引:0,他引:1
Two species of Pseudomonas chromosomally tagged with gfp, which had shown antagonistic activity against the tomato pathogen Ralstonia solanacearum in a previous study, were assessed for their impact in the rhizosphere of maize. Plant growth characteristics, numbers of indigenous heterotrophic bacteria, changes in the bacterial community structure according to the r/K strategy concept, and shifts in MIDI-FAME profiles of culturable bacterial fractions as well as total rhizosphere microbial communities were determined in relation to seed and soil treatment with the exogenous pseudomonads. The maize rhizosphere proved to be a suitable habitat for the introduced P. chlororaphis IDV1 and P. putida RA2, which showed good survival after introduction. However, both inoculants showed a small growth-reducing effect towards maize, which might have been caused by the high densities of inoculants used (i.e. competition for nutrients and action of metabolites produced) and/or changes in microbial community structure (both culturable bacterial fraction and the total microflora). Probably, an altered balance among the indigenous maize rhizosphere populations occurred. Thus, the culturable bacteria, as well as the total microflora in the rhizosphere, changed in response to the introduced pseudomonads, and their development was dependent on the growth stage of the plant. The FAME analyses showed that these microbial communities comprised different populations, and were separated according to, first, the method used (direct versus cultivation-based), second, sampling time, and, finally, inoculation level. 相似文献
88.
Journal of Plant Diseases and Protection - A total of twenty-five isolates of species Phytophthora cactorum, P. citrophthora, Pythium dissotocum complex, Py. aphanidermatum, Globisporangium... 相似文献
89.
Henrik Eckersten Antje Herrmann Alois Kornher Magnus Halling Erik Sindhøj Elisabet Lewan 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):151-165
Abstract In recent decades European silage maize production has extended northwards, into Scandinavia, and the importance of maize in fodder production has increased substantially. For the northward expansion of maize production it is of interest to evaluate both the role of climate change that has occurred already, and scenarios for possible future climate change. The aim of this study was to assess for Swedish climatic conditions, the annual variation in silage maize yield and quality (dry weight and starch contents) of cultivars currently grown in Germany. The MAISPROQ simulation model currently used in German maize production was applied to evaluate the effects of (i) cultivar differences (four cultivars; four sites; 2003–2009), (ii) intra-regional variation among ten sites representing three regions (two cultivars; 2003–2009), and (iii) climatic variability among two historical periods during 1961–2009 and three future periods during 2011–2100 using A2-emission climate scenarios and the Delta-method (two cultivars; four sites). Forage quality assessments strongly influenced the assessments of harvest time and thereby the yield. Changes in simulated yield of the tested cultivars were high for the past climate, but relatively small under future climatic conditions due to earlier harvest caused by improved forage quality. By the end of the 21st century an appropriate fodder quality would be achieved every year in the south of Sweden, whereas in the middle of Sweden (60°N) about 30% of the years would not be successful, even for the earliest cultivar. In the east, increased water stress counteracted the positive effect of a prolonged growing season. It was concluded that adaptation of field experiments to model calibration requirements remains to be done, in order to enable extrapolation of observations from Swedish field trials to a changing future climate. 相似文献
90.
Root biomass dynamics in a semi-natural grassland exposed to elevated atmospheric CO2 for five years
Erik Sindh?j Olof Andrén Thomas K?tterer Mark Marissink Roger Pettersson 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):50-59
The effects of elevated atmospheric CO2 on root dynamics were studied in a semi-natural grassland in central Sweden during five consecutive summer seasons. Open-top chambers were used for ambient and elevated (+350 μmol mol?1) concentrations of CO2, and chamberless rings were used for control. Root dynamics were observed in situ with minirhizotrons during the five summers and root biomass production was measured with root in growth cores during the last two years, from which total root biomass was estimated for each of the five years. The elevated CO2 treatment showed both a greater increase in root numbers during the early summer and a greater decline in root numbers during autumn and winter than the ambient CO2 treatment. Mean root production under elevated CO2 was 50% greater than ambient CO2 during the five years, and the difference increased from +25% in the first year to +80% in the last two years. Conversely, during the same period, the elevated to ambient CO2 difference in shoot biomass decreased from +50% to +5%. This resulted in a dramatic change in root to shoot ratios in elevated CO2 compared with the ambient treatment, which increased from ?15% in 1996 to +70% in 2000. Similar differences were seen between elevated CO2 and the chamberless grown control plants, where root to shoot ratios increased steadily from ?47% in 1996 to +27% in 2000. Less dynamically, the root to shoot ratios of ambient CO2 grown plants compared with the chamberless control plants were consistently ?29%±6% during the experimental period. In conclusion, during the 5 years this grassland was studied, there was a clear shift in plant biomass partitioning from above to below ground for plants exposed to elevated CO2. 相似文献