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1.
N. Ruff P. Lavens J.-Z. Huo P. Sorgeloos H.J. Nelis A. De Leenheer 《Aquaculture International》2001,9(2):115-126
The nutritional effect of vitamin E in dietsfor Litopenaeus vannamei postlarve (PL19)was investigated. Four formulated diets withdifferent combinations of α-tocopherylacetate (α-TA), ascorbic acid (AA) andhighly unsaturated fatty acids (HUFA) weretested, using four replicates. No significant differences in survival wereobserved among treatments after 34 days offeeding. However, shrimp fed with a dietcontaining 2% fish oil (low n-3 HUFA content),200 mg.kg?1 α-TA and100 mg.kg?1 AA (diet H/E/C) showedsignificantly better growth than those fed adiet supplemented with 5% fish oil (high n-3HUFA content), 200 mg.kg?1 α-TA and100 mg.kg?1 AA (diet H+/E/C). Shrimp fedwith a diet containing 5% fish oil,900 mg.kg?1 α-TA and100 mg.kg?1 AA (diet H+/E+/C) showed a significantly higher tissue level of n-6 PUFAthan postlarvae fed diet H+/E/C. No definiteconclusion could be drawn about a possibleinteraction between α-TA and AA, since acomparison of the diet containing 5% fish oil,200 mg.kg?1 α-TA and700 mg.kg?1 AA (H+/E+/C+) and the dietH+/E/C did not show any significant differencesin any of the measured parameters. Theantioxidative status of the shrimp tissue(measured by means of the thiobarbituric acid(TBA) assay and expressed as nM malonaldehyde(MA) per gramme dry weight) was equal for alltreatments. Nevertheless, there was a slightlylower MA value with the diet H+/E/C+,indicating that AA may be an effectiveantioxidant in the aqueous phase and at thewater/lipid interface of the tissue. The tissuelevels of α-T and AA were highlydependent on the amounts in diets and nocorrelation between α-T and AAincorporation could be observed. 相似文献
2.
P. Schlotzhauer P. A. Nelis S. Bollmus A. Gellerich H. Militz W. Seim 《Wood material science & engineering》2017,12(3):149-157
The total hardwood timber stock of German forests is fast growing. The lack of knowledge concerning test standards, product standards and sorting criteria makes it difficult to expand the processing and marketing of hardwoods into the field of construction usage. Strength and stiffness data derived from small, defect-free specimens do mostly exist, but in order to be able to insert hardwoods into building applications, data derived from real size specimens is needed. Subsequently, the results of these two different specimen categories need to be correlated and the so-called size effect needs to be quantified and qualified. This paper aims to analyze the size effect of defect-free compression, bending and tensile specimens for the six European hardwood species maple (Acer spp.), birch (Betula pendula), beech (Fagus sylvatica), ash (Fraxinus excelsior), oak (Quercus spp.) and lime (Tilia spp.). They are tested exclusively parallel to grain. Regarding the compression strength for maple, birch and ash, the specimen dimensions did not influence the compression strength value. For beech, oak and lime, it was observed that compression strength increased as the specimen volume was increased. The bending strength of all species decreased as the specimen dimensions increased. Concerning the tensile strength, a clear statement on whether dimensions influence the tensile strength value is not possible. Further research with adjusted specimen sizes, specimen shapes and machine set-ups is needed. Regarding the compression and bending MOE, in most cases, the dimensions did not influence the MOE values. In tensile testing, MOE values differed significantly for the different specimen sizes. Whether these differences were due to slightly different test set-ups in the different sizes or a true size effect could not be answered conclusively. 相似文献
3.
Pharmacokinetics of florfenicol after treatment of pigs with single oral or intramuscular doses or with medicated feed for three days 总被引：4，自引：0，他引：4
Voorspoels J D'Haese E De Craene BA Vervaet C De Riemaecker D Deprez P Nelis H Remon JP 《The Veterinary record》1999,145(14):397-399
The pharmacokinetics of florfenicol, a structural analogue of thiamphenicol, were studied in six pigs after single oral and intramuscular doses of 15 mg/kg bodyweight, and after feeding them with medicated feed containing 250 mg/kg for three days, a concentration which provided approximately the same dose rate of the drug. The oral doses contained a specially prepared pelleted formulation of the drug. The bioavailability of the drug was similar for the oral and intramuscular doses. Florfenicol was absorbed rapidly from the feed and its concentration in plasma remained between 2 and 6 microg/ml - above the minimum inhibitory concentration values for common pig pathogens - during the three days. 相似文献
4.
N. Ruff P. Lavens J.-Z. Huo P. Sorgeloos H.J. Nelis A. De Leenheer 《Aquaculture International》2002,9(2):115-126
The nutritional effect of vitamin E in dietsfor Litopenaeus vannamei postlarve (PL19)was investigated. Four formulated diets withdifferent combinations of -tocopherylacetate (-TA), ascorbic acid (AA) andhighly unsaturated fatty acids (HUFA) weretested, using four replicates.No significant differences in survival wereobserved among treatments after 34 days offeeding. However, shrimp fed with a dietcontaining 2% fish oil (low n-3 HUFA content),200 mg.kg–1 -TA and100 mg.kg–1 AA (diet H/E/C) showedsignificantly better growth than those fed adiet supplemented with 5% fish oil (high n-3HUFA content), 200 mg.kg–1 -TA and100 mg.kg–1 AA (diet H+/E/C). Shrimp fedwith a diet containing 5% fish oil,900 mg.kg–1 -TA and100 mg.kg–1 AA (diet H+/E+/C) showed a significantly higher tissue level of n-6 PUFAthan postlarvae fed diet H+/E/C. No definiteconclusion could be drawn about a possibleinteraction between -TA and AA, since acomparison of the diet containing 5% fish oil,200 mg.kg–1 -TA and700 mg.kg–1 AA (H+/E+/C+) and the dietH+/E/C did not show any significant differencesin any of the measured parameters. Theantioxidative status of the shrimp tissue(measured by means of the thiobarbituric acid(TBA) assay and expressed as nM malonaldehyde(MA) per gramme dry weight) was equal for alltreatments. Nevertheless, there was a slightlylower MA value with the diet H+/E/C+,indicating that AA may be an effectiveantioxidant in the aqueous phase and at thewater/lipid interface of the tissue. The tissuelevels of -T and AA were highlydependent on the amounts in diets and nocorrelation between -T and AAincorporation could be observed. 相似文献
5.
Two series of feeding experiments were conducted to study the feasibility of using decapsulated Artemia cysts for direct feeding to ornamental fish. The first series evaluated the dietary values of the dried and the brine decapsulated Artemia cysts against two conventional live feeds, Artemia nauplii and Moina for adults and fry of the guppy, Poecilia reticulata Peters. In the second series, brine cysts were used for feeding to fry of four other important ornamental fish species, viz. platy, Xiphophorus maculatus (Günther), swordtail, X. helleri (Heckel), molly, P. sphenops Cuvier & Valenciennes and black neon tetra, Hyphessobrycon herbertaxelrodi Géry, and the results were compared with those fed Moina. Evaluation of the performance of the fish fed the various diets was based on stress resistance, growth and survival of the fish. Our findings indicated that decapsulated cysts could be used as a substitute for Artemia nauplii or Moina in freshwater ornamental fish culture. Apart from being a hygienic off‐the‐shelf feed, the direct use of the cysts also signifies a new area of application for low‐hatch cysts in the ornamental fish industry, with concomitant saving in feed costs. 相似文献
6.
Lavens Merchie Ramos A. Leon-Hing Kujan A. Van Hauwaert Pedrazzoli Nelis & A. De Leenheer 《Aquaculture Nutrition》1999,5(3):205-209
A culture trial was performed using five levels of ascorbic acid 2-monophosphate (AmP at 0, 10, 100, 1000 and 2000 mg kg−1 diet, expressed as active ascorbic acid, AA) in a semipurified diet for early postlarval Penaeus vannamei. The experiment started 10 days after metamorphosis of the mysid larvae into postlarvae (=PL10). Each treatment was run in four replicates. P. vannamei postlarvae showed significantly better growth according to dietary AA level after 25 days of feeding, i.e. at PL36 stage. Whereas the dry weight of PL36 in the control treatment (0 mg AA kg−1 diet) was only 2 mg, supplementation of 1000 mg AA kg−1 increased the shrimp dry weight up to 18 mg. However, the growth in the other treatments was not significantly different from the control. Fitting a broken-line regression to the biomass yield demonstrated an optimal dietary level of 130 mg AA kg−1 diet. There were no differences observed among the treatments in stress resistance of postlarval P. vannamei to a salinity shock. 相似文献
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8.
The twitch procedure in horses attenuates the increase in the heart rate evoked by pain-inducing stimuli and the reaction of the animals to such stimuli. Endorphin systems are probably involved in the effectiveness of the twitch, since its action is blocked by naloxone and its application increases plasma concentrations of immunoreactive beta-endorphin. The mode of action of the twitch cannot be explained by the generally accepted theory of divertive pain and may resemble that of classical acupuncture. 相似文献
9.
Vansnick E Vercammen F Bauwens L D'Haese E Nelis H Geysen D 《Veterinary journal (London, England : 1997)》2005,170(2):249-256
Paratuberculosis is a chronic intestinal disease of ruminants caused by Mycobacterium avium subspecies paratuberculosis (Map). Very little is known about the status of paratuberculosis in European zoos. In this study, the presence of Map in the animal collection of the Royal Zoological Society of Antwerp (RZSA) was investigated. Faecal and post mortem samples from 48 ruminants were used to set up cultures. DNA from faeces, tissue and positive cultures were tested by IS900 polymerase chain reaction (PCR). Additionally, 448 serum samples were tested with an ELISA kit. All culture samples were negative whereas PCR gave three positives on biopsy samples and one positive on faecal samples. With the ELISA, 21 sera could be classified as positive. There is evidence that Map is present in the RZSA but no high level faecal shedders could be detected. Further investigations are required in other European Zoos in order to complete the picture of Map infections. 相似文献
10.
Commercial enzymatic membrane filtration (MF) tests for total coliforms (TC) and Escherichia coli in drinking water, based on β-galactosidase (TC) or β-glucuronidase (E. coli) detection take 18–24 h to complete. They either use chromogenic substrates (e.g., X-gal, X-gluc) or fluorogenic ones, particularly 4-methylumbelliferyl-glycosides. The latter afford improved detectability and, under particular conditions reduce the detection time to approximately 8 h. As part of our efforts to further enhance the speed of enzymatic MF tests, we examined two more advanced, two-step approaches. The first one involves microcolony formation in a short growth phase, followed by a separate enzyme assay using 4-trifluoromethylumbelliferyl-glycosides plus a membrane permeabilizer, and reading under a UV-lamp. For E. coli this type of test takes 5.5 h but field studies revealed a high false-negative rate. Switching from visual microcolony detection to instrumental single cell detection with the aid of a laser scanner (ChemScan) resulted in tests for E. coli and TC of 3.5 h. Both procedures involve enzyme induction (3 h) in the target cells, followed by cell labelling (30 min) using fluorescein-di-β-D-glycosides and laser scanning (3 min) of the membrane filter. Application of the ChemScan E. coli test to naturally contaminated well and surface, as well as uncontaminated well and tap (n=149) water samples has indicated >90 % agreement, and equivalence with reference methods. The false-negative rate was 3.0–6.0% versus Chromocult Coliform and m FC agar, respectively. In 10 out of 149 samples, low numbers (1–3) of the target organisms were detected by laser scanning and not by conventional plate methods. These one-working day tests for TC and E. coli would be particularly useful for emergency monitoring of drinking water. 相似文献