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71.
R O Waelchli H Lutz M Hermann E Eggenberger 《Schweizer Archiv für Tierheilkunde》1992,134(10):471-482
Eighteen healthy foals were studied from birth until 2 months of age. Blood samples were obtained at the following times: presuckle, 30 hours, 1, 3, 5, 7 and 9 weeks of age. Changes in serum P, Mg, Ca, Na, K, Cl, iron, AP, ASAT, ALAT, GGT, GLDH, CK, lipase, urea, creatinine, cholesterol, triglyceride, uric acid, protein and fibrinogen and in plasma total solids were examined and the values compared to reference values of adult horses. There were characteristic age related changes in several parameters. Single measurements should be interpreted cautiously to allow for individual variations. 相似文献
72.
Arthur W. A. M. De Cock Afra Neuvel Günther Bahnweg Johanna C. J. M. De Cock Hermann H. Prell 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(5):277-289
Thirteen strains ofPhytophthora porri from five different hosts were compared with respect to their morphology, cardinal temperatures for growth, pathogenicity to leek and cabbage and restriction fragment patterns of mitochondrial DNA. Morphology of vegetative growth was rather similar in most isolates. Those characters which differed among isolates showed overlapping variability and could not be used to distinguish groups, with the exception of production of oogonia and sporangia and the antheridium type. Considerable differences were found in restriction patterns of mitochondrial DNA, isolates from the same host mostly showing identical patterns. Isolates from differentAllium species showed relatively similar restriction patterns if compared to the other isolates. Isolates fromBrassica oleracea proved to be a homogeneous group, quite different from the others with respect to restriction patterns, production of sporangia, production of oogonia, antheridium type and pathogenicity. One isolate, CBS 366.59, isolated from and pathogenic toA. porrum, deviated in many characters from the other isolates. It showed the restriction patterns ofPhytophthora nicotianae and also the high cardinal temperatures for growth typical for this species. The sporangia, however, were distinctly non-papillate and the majority of antheridia was of the paragynous type. 相似文献
73.
Hermann Restrepo-Diaz Manuel Benlloch Ricardo Fernndez-Escobar 《Scientia Horticulturae》2008,116(4):409-413
Three-month-old mist-rooted ‘Picual’ olive cuttings were transplanted into 2-l plastics pots containing perlite as substrate and fertigated with a complete nutrient solution containing 0.05, 0.1 or 2.5 mM KCl depending on the experiment. In the first experiment, plants were sprayed with RbCl (Rb+ is a K+ analog) at a rate of 4% at 63 days after transplanting (DAT). Foliar Rb+ uptake through leaves increased with K+ concentration in the nutrient solution, indicating that foliar Rb+ uptake was lower when plants were K+ deficient than when they were adequate. On the contrary, it was observed that translocation of Rb+ from leaves to other organs of the plant was higher under K+ deficiency conditions. In the second and third experiments, when differences appeared on shoot length due to K+ nutritional status (0.05 or 2.5 mM KCl) at 63 DAT, a group of plants were subjected to water stress during 7 weeks. On the other hand, another group of plants (control plants) did not receive any water stress treatment during the experiments. After this period of 7 weeks, all plants were sprayed with RbCl at 4%. Leaf K+ concentration diminished in water-stressed plants independently of plants nutritional status. Foliar Rb+ uptake through leaves was restricted by water stress either in plants with low K+ (0.05 mM KCl) or plants with high K+ (2.5 mM KCl). Translocation of Rb+ from leaves was greater under water stress conditions in both K+ nutritional statuses. In conclusion, the results obtained could explain the irregular response in olive trees to foliar K+ sprays, particularly, when they grow in rainfed orchards. 相似文献
74.
75.
Rural people in Africa periodically rely on wild fruits to supplement their diet and to generate cash income. However, scientific
evidence on the economics of using indigenous fruit tree (IFT) products is scarce. The objective of the study was to fill
in some of the gaps for which farm-household surveys were conducted in Zimbabwe during 1999–2000. Gross margins and returns
to labour in collection, use and sale of products of Uapaca kirkiana (Muell. Arg., Wild Loquat), Strychnos sp. (S. cocculoides (Baker) and S. spinosa (Lam.), Monkey Orange) and Parinari curatellifolia (Planch. ex. Benth., Fever Tree) were compared with other farming activities. A random sample of over three hundred households
in the Murehwa Communal and the Takawira Resettlement Areas was interviewed to gather income and expenditure data. Additionally,
income, expenditure and labour allocation of 39 households were closely monitored for one year. Results indicated that the
majority of rural households benefited from consumption and sale of indigenous (IF), although the extent varied among households.
Within the households, children were the main consumers of fruits. Marketing of IF are carried out by women who used the receipts
to purchase household goods. While U. kirkiana fruits were more important in generating cash income than others, fruits of P. curatellifoliawere important for home consumption during periods of food shortages. The gross margins for collection of IFT products were
lower than for livestock and crop production. However, returns to labour from collection and use of IFT products were considerably
greater than from other activities including gardening and livestock rearing. The study indicates that collection of IFT products
is an efficient labour allocation strategy in Zimbabwe.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
76.
Marcus?Schmidt Kerstin?Sommer Wolf-Ulrich?KriebitzschEmail author Hermann?Ellenberg Goddert?von?Oheimb 《European Journal of Forest Research》2004,123(2):167-176
The endozoochorous and epizoochorous dispersal of vascular plant species by roe deer (Capreolus capreolus) and wild boar (Sus scrofa) was investigated in forest areas of Schleswig-Holstein and Lower Saxony, Germany. The primary aim of this study was to learn about which plant species and in what numbers diaspores are dispersed by the two wild ungulate species. In particular, the significance of zoochory for species composition and biodiversity of forests was evaluated. Fresh faecal pellets were collected from April–November 2001 in the forests of the two study areas. In addition, the coats and hooves of shot roe deer and wild boar were brushed out. The number of viable seeds was determined by greenhouse germination (seedling emergence method). The samples were spread in trays over sterilized soil from the study forests and were kept under controlled conditions in the greenhouse for 12 months. A total of 2,473 individuals from 77 vascular plant species were recorded. While roe deer exceeded wild boar concerning seed contents in the faeces, the significance of roe deer for epizoochorous dispersal was relatively low compared with wild boar. An analysis of the habitat preference of the vascular plant species dispersed by the two ungulate species revealed a high proportion of species growing in forests as well as in the open landscape, and also of non-forest species, while woody plants and herbaceous species closely tied to forest habitats were severely underrepresented. We also discuss consequences for forest ecology and nature conservation. 相似文献
77.
This paper describes a method to provide improved probability estimates that exposure to a specific dose of an airborne infectious pathogen will result in animal infection. Individual animals were exposed to a specific dose of airborne pathogen. Following exposure, animals were individually housed and monitored for evidence of infection. The detection of specific antibodies and/or the pathogen in diagnostic specimens was evidence that the exposure dose resulted in infection. If replicated over a range of doses, the results can be used to derive a dose-response curve for a variety of animal species and infectious pathogens. This information is useful in estimating the likelihood of infection associated with exposure to airborne infectious microorganisms. Applications include predicting the risk of transmission associated with exposure to airborne pathogens, modeling the transmission of airborne pathogens, and determining requirements for effective exposure doses for vaccines delivered in aerosols. 相似文献
78.
Clercx C Reichler I Peeters D McEntee K German A Dubois J Schynts E Schaaf-Lafontaine N Willems T Jorissen M Day MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):843-849
This study describes the clinical, immunologic, genetic, and pathologic features of Irish Wolfhounds with rhinitis/bronchopneumonia syndrome. The dogs examined were from Belgium, The Netherlands, UK, Canada, Germany, and Switzerland. Signs included transient to persistent mucoid or mucopurulent rhinorrhea, cough, and respiratory dyspnea. Radiographic, rhinoscopic, and bronchoscopic findings were variable. Analysis of ciliary ultrastructure was performed in 5 affected dogs, but no characteristic primary ciliary defects (primary ciliary dyskinesia) were detected. Serum and bronchoalveolar lavage fluid (BALF) concentrations of IgA, IgG, and IgM were determined in some affected dogs and clinically normal Irish Wolfhounds. Serum IgA concentration was below the reference range in 5 of 8 affected dogs tested, whereas BALF IgA concentration was above the normal range in 2 affected adult dogs. The CD4 to CD8 lymphocyte subset ratio (CD4:CD8) in peripheral blood was tested in 3 affected dogs and was within the normal range. BALF CD4:CD8 was tested in 1 affected dog and was higher than the normal range. Decreased neutrophil phagocytosis was observed in 1 of the 4 dogs tested. Analysis of pedigrees of the Belgian, Canadian, German, and Swiss dogs revealed common ancestry, suggesting a heritable syndrome. 相似文献
79.
Truyen U Isa G Gerbermann H Bogner KH Banzhaf K Köstler M Pauels FJ Czerny CP Wittkowski G 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(5-6):197-202
In Bavaria a BHV-1 eradication program was initiated in 1986 and was changed to a compulsory program in 1998. The eradication success increased progressively from < 50% in 1986 to 87% of the farms in 2002. BHV 1-free farms are controlled by bulk milk serology twice a year along with blood serology in animals that are negative but from herds where positive field virus infected animals are present. All serological tests are performed with an indirect ELISA test, all positive results are confirmed by a gB ELISA. Currently about 100.000 virus infected cattle are in Bavarian herds, approximately 80% of these animals are in heavily infected herds (> 10 infected animals). These herds comprise about 5% of all Bavarian herds. The eradication of the virus in these heavily infected herds is the most diifficult, whereas the prevention of new infections appears controllable. In this review current problems in BHV1 eradication are named and possible improvements are discussed. 相似文献
80.
Weishaupt MA Hogg HP Wiestner T Denoth J Stüssi E Auer JA 《American journal of veterinary research》2002,63(4):520-527
OBJECTIVE: To develop and validate a novel instrumented treadmill capable of determining vertical ground reaction forces of all 4 limbs simultaneously in horses. SAMPLE POPULATION: Data obtained while a horse was walking and trotting on the treadmill. PROCEDURE: 18 piezo-electric force transducers were mounted between the treadmill frame and supporting steel platform to measure the actual forces at the corresponding bearing points. Each of the 18 sensor forces is equal to the sum of the unknown hoof forces weighted with the transfer coefficients of the corresponding force application points. The 4 force traces were calculated, solving at each time point the resulting equation system, using the Gaussian least-squares method. System validation comprised the following tests: determination of the survey accuracy of the positioning system, determination of the natural frequencies of the system, linearity test of the force transfer to the individual sensors, determination of superimposed forces with the treadmill-integrated force measuring system (TiF) in a static configuration, and comparison of vertical ground reaction forces determined simultaneously by use of TiF and force shoes mounted on the forelimbs of a horse. RESULTS: Comparison between static test loads and TiF-calculated forces revealed deviations of < 1.4%. Force traces of TiF-calculated values and those recorded by use of the force shoes were highly correlated (r > or = 0.998). CONCLUSIONS AND CLINICAL RELEVANCE: This instrumented treadmill allows a reliable assessment of load distribution and interlimb coordination in a short period and, therefore, is suitable for use in experimental and clinical investigations. 相似文献