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221.
Nora M. BiermannNora Rindler MSc Heinz Hans Florian Buchner 《Journal of Equine Veterinary Science》2014
This study assessed the therapeutic effect of pulsed electromagnetic fields (PEMF) on the backs of Polo ponies by measuring mechanical nociceptive thresholds (MNTs) and induced back movement. Twenty Polo ponies in regular training and competition were assigned to two groups. A double-blind, placebo-controlled, crossover field study with PEMF was performed, consisting of two 10-day therapy periods. At the beginning and end of each therapy period, the MNTs from 25 sites of the horses backs were assessed by pressure algometry (PA), and induced back movement was evaluated by flexion testing. Baseline MNTs were generally low, with means between 6.4 and 10.0 kg/cm2. Significant changes in MNTs occurred nearly equally after both the PEMF and the placebo control treatments (at 5 of 25 or 6 of 25 sites, respectively) and without any regular pattern. Changes were evident, predominantly as decreased MNTs within and between treatment periods. Flexion testing revealed stiffness or avoidance in 19 of 20 horses. Results of the flexion testing showed an increased number of physiologic reactions at the end of both treatment periods compared with baseline values. The effect of PEMF on back pain and range of induced back movement could not be proven in this study. Although pretherapy values indicated the horses might have experienced back pain, all horses were still actively used in sport, and back pain might not have been severe enough to allow a significant effect to be demonstrated. 相似文献
222.
According to the electron microscopic investigations the most evident sign of the phase of the active involution of the mammary gland in cattle is the occurrence of different great vacuoles with a diffuse content in the cytoplasma of the secretory cells till the 30th day after the beginning of the dry period. Secretory cells which go over in the rest phase show a great reduction of the cell organelles and many filaments and secondary lysosomes or residual bodies. One can observe many macrophages and lymphocytes in the partly enlarged intercellular rooms between the secretory cells and the myoepithelial cells. The myoepithelial cells are adapting to the changing forms of alveoli. The phase of the colostrogenesis is characterised by the enlargement of the cell organelles and the reappearance of vacuoles. 相似文献
223.
It was found that different procedures of heat treatment influenced the true digestibility of nitrogen and of the amino acids in cereals. In view of the fact that under practical feeding conditions pelleting is the most widely used procedure studies were made in trials with young pigs fed coarsely ground barley or maize of pellets of these as sole diet. 相似文献
224.
Resendes A Segalés J Balasch M Calsamiglia M Sibila M Ellerbrok H Mateu E Plana-Durán J Mankertz A Domingo M 《Veterinary research》2004,35(1):83-90
The objective of this study was to evaluate the effect of a commercial vaccine adjuvant on the clinical and pathological outcome of PCV2 experimentally infected 8 to 9-week-old conventional pigs. Forty-four pigs were divided into four groups: non-infected control pigs, pigs that received a vaccine adjuvant, pigs inoculated with PCV2, and pigs inoculated with PCV2 together with the vaccine adjuvant. Infection was monitored until 69 days post-inoculation (PI). Some PCV2 inoculated pigs had hyperthermia, but no other clinical signs were recorded. No characteristic PMWS gross or microscopic lesions were observed in any of the pigs. PCV2 DNA was detected in lymphoid tissues by in situ hybridisation in 6 PCV2 inoculated pigs on day 69 PI. All PCV2 inoculated pigs seroconverted between days 21 and 49 PI, shortly after viremia detection. Moreover, viremia was detected between days 7 and 69 PI using PCR. A peak of the virus load was detected by real-time quantitative PCR between days 14 and 21 PI. There were no significant differences in the proportion of PCV2 positive serum and in the viral load between PCV2 and PCV2 + adjuvant inoculated pigs. Although PMWS was not reproduced in neither PCV2 nor PCV2 + adjuvant inoculated pigs, viremia detection and seroconversion indicated that all PCV2 inoculated pigs developed a chronic long-term asymptomatic infection. An increase of PCV2 replication was not observed in pigs inoculated with the adjuvant. These results indicate that the principle of immunostimulation may not be applicable under the experimental conditions used, suggesting that not all adjuvants used in commercial vaccines are capable of triggering mechanisms for PMWS development. 相似文献
225.
Freeman L. McEwen Gwen Ritcey Heinz Braun Richard Frank Brian D. Ripley 《Pest management science》1980,11(6):643-650
Residues were determined at 8-h intervals during the 48 h after application of endosulfan, leptophos, methamidophos, methomyl and mevinphos to head lettuce; of endosulfan, methamidophos and methomyl to cauliflower; and of parathion to onions and carrots. Residues of phosalone and parathion were measured on apple leaves 0, 1, 2, 4, 8 and 16 days after application. In addition, the portion of the residue on apple leaves that could be dislodged was measured, as well as the residues on gloves used to handle the apple foliage. There were large differences in the rates of disappearance of the insecticides, differences that must be known in determining safe re-entry periods for workers. 相似文献
226.
Brigitte Dorn Tomke Musa Heinz Krebs Padruot Men Fried Hans Rudolf Forrer 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(2):217-240
In order to replace copper fungicides in organic potato production, 53 copper-free preparations (CFPs) based on natural compounds,
including plant extracts and microorganisms, and five copper preparations were evaluated for their potential to control Phytophthora infestans, the pathogen that causes late blight of potatoes. In in vitro assays, 30% of the CFPs inhibited indirect germination of
sporangia, 26% mycelial growth and in growth chamber experiments, 21% efficiently reduced foliar blight of tomato plants.
In micro-plot field trials with applications twice a week, the copper preparations were the most effective and reduced foliar
blight by 99%. Of the CFPs tested, Oekofluid P, Mycosin and other sulphuric clays, and C-2000 reduced late blight the most,
from 63% to 37%. In small-plot trials in 2001, 2002 and 2004, 27 CFPs with different formulations and four copper preparations
were examined. In 2004, copper preparations at full and reduced rates and sulphuric clays were applied either weekly or according
to the decision support system Bio-PhytoPRE. With Bio-PhytoPRE, copper preparations reduced foliar blight of potatoes by 23–77%
and increased tuber yield by 2–28%, depending on the copper rate applied and year. With CFPs, maximal efficacy was 17% and
no effect on tuber yield was observed. In vitro and in vivo trials showed that the rainfastness and the persistence of CFPs
was low compared with copper preparations. This indicates that the failure of CFPs under field conditions is probably due
to a lack of stability under prevailing environmental conditions and not to a lack of efficacy. Until stable formulations
for CFPs are developed, an optimised and restricted use of copper fungicides using a decision support system could help to
control late blight in organic potato production and to reduce copper input into the environment. 相似文献
227.
228.
The Australian psyllid Ctenarytaina eucalypti has been accidentally introduced into many parts of the world. In America as well as in Europe it caused severe damage on Eucalyptus cut-foliage plantations. Insecticide treatments have proven to be expensive and not-sustainable. Therefore a biocontrol project was carried out in the Center for Biological Control at Berkely, California. The search for a monophagous parasitoid of the blue gum psyllid in the natural habitat in Australia and New Zealand was successful. After quarantine for elimination of hyperparasitoids the natural enemy Psyllaephagus pilosus has been released in Californian Eucalyptus plantations since 1993. It established itself rapidly, resulting in a decrease of the pest below the economic threshold. Following this impressive effect the parasitoid has also been released in some West European countries. The rapid spread over great territories was similar. The parasitization rates reached 100 percent, providing a sustainable control of the psyllid. In the last years several accidental introductions of C. eucalypti into Germany occurred. The first record in Saxony was in 2000 in the botanical garden of the Dresden University of Technology on Eucalyptus globulus. However, the spontaneous attack of the blue gum psyllid by P. pilosus during the next two years eradicated the infestation. To avoid a possible threat to natural ecosystems, the well-directed future use of exotic biological control agents against unintentionally introduced pests is in urgent need of a legal regulation at the EU or national level in Germany. The FAO and EPPO standards on this topic should be considered as a basis for this. 相似文献
229.
Anna Hover Fabien Buissart Yves Caraglio Christine Heinz François Pailler Merlin Ramel Michel Vennetier Bernard Prévosto Sylvie Sabatier 《Annals of Forest Science》2017,74(2):39
Key message
The chronology of periods of organogenesis and elongation is highlighted in Pinus halepensis.The two first growth units of an annual shoot are preformed inside the bud during the previous year. The following growth units are formed during the spring or summer of the current year.Context
Analysis of annual shoot length growth phenology is crucial to assess the impact of climate change on tree production. Little is known about the basic growth characteristics and the phenology of pines.Aims
The present study disentangles the roles of shoot organogenesis vs elongation in the annual growth cycle of the polycyclic Aleppo pine.Methods
Growth of young Pinus halepensis trees was monitored monthly for 1 year. At each monitoring date, the bud content and meristem dimensions of the main stem shoots apices were analyzed.Results
The two first growth units of an annual shoot are preformed inside the bud during the previous year. The following growth units are formed during the spring or summer of the current year. The gap between a shoot organogenesis and its elongation may vary from 1 month, for the last growth unit, to half a year, for the first growth units.Conclusion
Our results underline the importance of taking seasonal environmental conditions from both the previous and the current year into account, in order to study the plasticity of annual shoot growth and its response to climate change and variability.230.