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排序方式: 共有112条查询结果,搜索用时 31 毫秒
61.
Azim Saiful Rasmussen Jesper Nielsen Jon Gislum René Laursen Morten Stigaard Christensen Svend 《Precision Agriculture》2019,20(6):1199-1210
Precision Agriculture - The global spatial accuracy of ortho-mosaics based on images from consumer-grade unmanned aerial vehicles (UAVs) is relatively low. The use of ground control points (GCPs)... 相似文献
62.
Saevik BK Bergvall K Holm BR Saijonmaa-Koulumies LE Hedhammar A Larsen S Kristensen F 《Veterinary dermatology》2004,15(3):137-145
A randomized, double blind, placebo-controlled multicentre clinical trial of 12 weeks' duration was undertaken in 60 dogs with atopic dermatitis to evaluate the steroid sparing effect of essential fatty acid supplementation. The dogs were randomly assigned to receive either a combination of borage seed oil and fish oil or a placebo, in addition to prednisolone tablets. All dogs received a standardized basal diet. Owners of the dogs recorded pruritus daily using a 10 cm visual analog scale and the dosage of prednisolone was established based on the pruritus score, according to written instructions. The dosage of prednisolone and the use of any concurrent treatment (shampoo and/or ear-cleanser) were recorded by the owner on a daily basis. The investigators graded the skin lesions at days 0, 42 and 84. The use of prednisolone during the test period was lower in the active group, but the difference was not statistically significant (P = 0.32). The test period was sequentially divided into 43-84, 50-84, 57-84, 64-84, 71-84 and 78-84 days. On day 64, the difference between the active group and the placebo group reached statistical significance (P = 0.04) with an increasing difference towards the end of the study. A statistically significant reduction in the pruritus scores and the total clinical scores from day 0 to day 84 was apparent in both groups (P < 0.0001). At the end of the study, both the pruritus score and the total clinical score were lower in the active group. Our findings indicate a steroid sparing effect of essential fatty acid supplementation in canine atopic dermatitis and, furthermore, that there is a time lag before the effect is attained. 相似文献
63.
Net joint kinetics in the limbs of pigs walking on concrete floor in dry and contaminated conditions
In pigs (Sus scrofa), joint disorders are frequent leg problems, and inappropriate pigpen floors and slippery floor conditions may contribute to these problems. Therefore, this study first aimed to quantify the net joint kinetics (net joint moments and net joint reaction forces) in the forelimbs and hindlimbs of healthy pigs walking on solid concrete floors. Second, this study aimed to examine the effect of floor condition on the net joint kinetics. Kinematic (50-Hz video recordings) and kinetic (1-kHz force plate measurements) data were collected from 30 pigs and combined with body segment parameters from a cadaver study. Net joint kinetics was calculated by using a 2-dimensional inverse dynamic solution. Inverse dynamics have, to our knowledge, not been applied in pigs before. Dry, greasy, and wet floor conditions were tested with 10 pigs each. In the forelimbs, peak joint moment was less (P < 0.01) on greasy (0.184 +/- 0.012 Nm/kg, moment of force per kg of BW) than on dry (0.232 +/- 0.012 Nm/kg) or wet (0.230 +/- 0.012 Nm/kg) conditions. Additionally, the minimum forelimb joint moment was more negative (P < 0.05) on greasy (-0.119 +/- 0.009 Nm/kg) than on dry or wet (both -0.091 +/- 0.009 Nm/kg) conditions. The forelimb joint reaction forces and the hindlimb joint kinetics were unaffected by floor condition. The greatest (P < 0.001) joint moments occurred in the shoulder (-0.376 +/- 0.007 Nm/kg), elbow (0.345 +/- 0.009 Nm/kg), hip (0.252 +/- 0.009 Nm/kg), and tarsal (0.329 +/- 0.009 Nm/kg) joints, which may be related to the greater incidence of joint diseases in some of these joints. In conclusion, the forelimb joints of the pigs responded more markedly to floor condition than did their hindlimb joints, probably because the forelimbs carry more weight. In particular, between the dry and greasy floor conditions, the joint loading differed, most likely because the pigs adapted to a potentially slippery surface. 相似文献
64.
Mary B. Nabity Kendal E. Harr Melinda S. Camus Bente Flatland Linda M. Vap 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(1):9-21
The purpose of this document is to provide total allowable error (TEa) recommendations for commonly analyzed hematology measurands for veterinary personnel. These guidelines define relevant terminology and highlight considerations specific to hematology measurands. They also provide reasons and guidelines for using TEa in instrument performance evaluation, including recommendations for when the total observed error exceeds the recommended TEa. Biological variation‐based quality specifications are briefly discussed. The appendix describes the derivation of the hematology TEa recommendations and provides resources for external quality assurance/proficiency testing programs and a worksheet for implementation of the guidelines. 相似文献
65.
O. L. Nielsen J. C. Jensenius P. H. Jrgensen S. B. Laursen 《Veterinary immunology and immunopathology》1999,70(3-4):309-316
Mannan-binding lectin (MBL) is a serum collectin which is believed to be an opsonin of the innate immune defence against various microorganisms. MBL is a minor acute phase reactant in man. We investigated the concentration of serum MBL in chickens infected with infectious bronchitis virus (IBV) and infectious laryngotracheitis virus (ILTV). The concentration of serum MBL increased about twofold (from approximately 6 to 12 μg/ml) due to these viral infections. The concentration peaked 3–7 days after infection with IBV, and 3–5 days after ILTV infection, depending on the ILTV strain used. The increased levels returned to normal values 6–10 days after infection. The results indicated that MBL is a minor acute phase reactant in chickens. 相似文献
66.
Marianne Arnemo Arturas Kavaliauskis Adriana Magalhaes Santos Andresen Marta Bou Gerd Marit Berge Bente Ruyter Tor Gjøen 《Fish physiology and biochemistry》2017,43(4):1065-1080
The shortage of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the international markets has led to increasing substitution of fish oil by plant oils in Atlantic salmon (Salmo salar) feed and thereby reducing the EPA and DHA content in salmon. However, the minimum required levels of these fatty acids in fish diets for securing fish health are unknown. Fish were fed with 0, 1 or 2% EPA or DHA alone or in combination of both over a period, growing from 50 to 400 g. Primary head kidney leucocytes were isolated and stimulated with Toll-like receptor (TLR) ligands to determine if EPA and DHA deficiency can affect expression of important immune genes and eicosanoid production. Several genes related to viral immune response did not vary between groups. However, there was a tendency that the high-level EPA and DHA groups expressed lower levels of IL-1β in non-stimulated leucocytes. These leucocytes were also more responsive to the TLR ligands, inducing higher expression levels of IL-1β and Mx1 after stimulation. The levels of prostaglandin E2 and leukotriene B4 in serum and media from stimulated leucocytes were lower in both low and high EPA and DHA groups. In conclusion, leucocytes from low EPA and DHA groups seemed to be less responsive towards immunostimulants, like TLR ligands, indicating that low levels or absence of dietary EPA and DHA may have immunosuppressive effects. 相似文献
67.
Steffensen SK Pedersen HA Labouriau R Mortensen AG Laursen B de Troiani RM Noellemeyer EJ Janovska D Stavelikova H Taberner A Christophersen C Fomsgaard IS 《Journal of agricultural and food chemistry》2011,59(22):12073-12082
Amaranthus hybridus and Amaranthus mantegazzianus are commonly cultivated and the entire young fresh plants consumed as vegetables in regions of Africa and Asia. A. hybridus and A. mantegazzianus were cultivated at four sites in three climate regions of the world: Santa Rosa, Argentina; Lleida, Spain; and Prague and Olomouc, both in the Czech Republic. The contents of flavonoids (isoquercitrin, rutin, nicotiflorin), hydroxybenzoic acids (protocatechuic acid, 4-hydroxybenzoic acid, vanillic acid), hydroxycinnamic acids (caffeic acid, p-coumaric acid, ferulic acid), hydroxycinnamyl amides (N-trans-feruloyltyramine, N-trans-feruloyl-4-O-methyldopamine), and betaines (glycinebetaine, trigonelline) were determined. The variation in phytochemical content due to species and cultivation site was analyzed utilizing the multivariate statistical methods of principal component analysis (PCA) and graphical model (GM). The Argentinean samples differed from the three other locations due to higher contents of most compounds. The samples from Spain and the Czech Republic differed from each other in the content of the negatively correlated metabolites trigonelline and the flavonoids. The two amaranth species were separated primarily by a higher content of trigonelline and the two hydroxycinnamyl amides in A. mantegazzianus. The GM showed that the quantities of the different analytes within each compound group were intercorrelated except in the case of the betaines. The betaines carried no information on each other that was not given through correlations with other compounds. The hydroxycinnamic acids were a key group of compounds in this analysis as they separated the other groups from each other (i.e., carried information on all of the other groups). This study showed the contents of polyphenols and betaines in the aerial parts of vegetable amaranth to be very dependent on growth conditions, but also revealed that some of the compounds (trigonelline and the two hydroxycinnamyl amides) may be useful as features of a taxonomic classification. 相似文献
68.
Photodegradation has been shown to play a role in plant litter degradation in some ecosystems, and therefore potentially in the global carbon cycle. To introduce photodegradation into models of carbon turnover we need an equation that relates mass loss to incident radiation. Based on experimental data from the literature we developed a linear equation for photodegradation as a function of light exposure. We also scaled up the results to global scale, based on global data on incident radiation and shading by plant cover. The results indicate that photodegradation plays a part in semi-arid environments and potentially some arctic and alpine environment. However, the percentage of global plant production decomposed by photodegradation is estimated to be less than 1% (range 0.5-1.6). Photodegradation is therefore important locally, but probably not very important for the global carbon budget. 相似文献
69.
Consumer attitudes towards castration of piglets and alternatives to surgical castration 总被引:1,自引:0,他引:1
Bente Fredriksen Anne Mette Sibeko Johnsen Ellen Skuterud 《Research in veterinary science》2011,90(2):352-6791
From three in-depth focus group studies and an internet based study concerning consumers attitudes towards surgical castration of piglets and alternatives, it can be concluded that Norwegian consumers are content with the current practice of castration using local anaesthesia. They accept castration as a necessary means to prevent the risk of boar taint in meat and thereby secure meat quality. Even though castration using anaesthesia is not a perfect solution, it is considered sufficient, and the consumers do not ask for alternatives. Most consumers were sceptical of immunocastration. The scepticism was mainly based on the fear of residuals in meat and unknown long-term consequences for the consumers. On the other hand the confidence in Norwegian control authorities is considerable, and will probably contribute to the maintenance of purchase habits even if immunocastration is to be introduced in Norwegian pig production. Castration without anaesthesia was characterized as completely unacceptable. 相似文献
70.
Annelin A Bjelland Frederik L Dolva Ane N?dtvedt Bente K S?vik 《Acta veterinaria Scandinavica》2014,56(1)