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排序方式: 共有350条查询结果,搜索用时 859 毫秒
91.
J.A.M. Missotten J. Michiels J. Goris L. Herman M. Heyndrickx S. De Smet N.A. Dierick 《Livestock Science》2007,108(1-3):232-235
In this trial two commercial probiotic products (Bactocell® and Adjulact® Pro) were investigated in vitro for their use as microbial inoculum for the production of fermented liquid feed (FLF) for pigs. Bactocell® was applied at a dose of 9 and 10 log10 CFU/kg and Adjulact® Pro at a level of 9 log10 CFU/kg. The FLF (control and treatments) was prepared with a water to feed ratio of 4:1 and run in batch for 72 h at 30 °C. The microbial population was followed with plate countings and the lactic acid, acetic acid and ethanol concentration was determined at different time points in the FLF. After 24 h, significant differences (P < 0.05) were found between the control and the Adjulact® Pro FLF for pH (4.7 vs 4.3), lactic acid (57.9 vs 91.5 mmol/L), acetic acid (23.1 vs 6.8 mmol/L), ethanol (24.5 vs 1.1 mmol/L), coliforms (7.2 vs 4.3 log10 CFU/mL) and E. coli (6.2 vs 4.4 log10 CFU/mL). Bactocell® addition did not alter the fermentation characteristics compared to the control FLF. After 72 h no significant differences between treatments were noted, except for the yeast count which was higher in the FLF inoculated with Adjulact® Pro. 相似文献
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Early detection of Johne’s disease (JD) caused by Mycobacterium avium subspecies paratuberculosis (MAP) is essential to reduce transmission; consequently, new diagnostic techniques and approaches to detect MAP or markers of early MAP infection are being explored. The objective was to identify biomarkers associated with MAP infection at 6 and 9 months after oral inoculation. Therefore, gene expression analysis was done using whole blood cells obtained from MAP-infected calves. All MAP-inoculated calves had a cell-mediated immune response (IFN-γ) to Johnin PPD specific antigens, and 60% had an antibody response to MAP antigens. Gene expression analysis at 6 months after inoculation revealed downregulation of chemoattractants, namely neutrophil beta-defensin-9 like peptide (BNBD9-Like), S100 calcium binding protein A9 (s100A9) and G protein coupled receptor 77 (GPR77) or C5a anaphylatoxin chemotactic receptor (C5a2). Furthermore, BOLA/MHC-1 intracellular antigen presentation gene was downregulated 9 months after inoculation. In parallel, qPCR experiments to evaluate the robustness of some differentially expressed genes revealed consistent downregulation of BOLA/MHC-I, BNBD9-Like and upregulation of CD46 at 3, 6, 9, 12, and 15 months after inoculation. In conclusion, measuring the expression of these genes has potential for implementation in a diagnostic tool for the early detection of MAP infection.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-014-0096-5) contains supplementary material, which is available to authorized users. 相似文献95.
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This paper has two purposes: To report the findings of a study of ethnic differences in cognition in a rural West Sumatran area; and to demonstrate the importance of ethnicity—in at least some contexts—for tailoring agricultural research to farmers' needs. A cognitive mapping technique, called a Galileo, was used to measure people's views of soil and its relation to people among three Indonesian ethnic groups living in the same area. Findings from participant observation and from collaborative agricultural fieldwork with farmers of all three ethnic groups are used to evaluate and interpret the Galileo results.Carol J. Pierce Colfer is currently Associate Professor at Sultan Qaboos University in the Sultanate of Oman. She is an anthropologist who served first as the farming systems researcher, and later as Team Leader of the Tropsoils-Indonesia project in Sitiung, with the University of Hawaii.Barbara Newton is Professor of Psychology at the University of Hawaii, West Oahu. She has had extensive experience with Galileo research and analysis. 相似文献
97.
Bonfil R Meÿer M Scholl MC Johnson R O'Brien S Oosthuizen H Swanson S Kotze D Paterson M 《Science (New York, N.Y.)》2005,310(5745):100-103
The large-scale spatial dynamics and population structure of marine top predators are poorly known. We present electronic tag and photographic identification data showing a complex suite of behavioral patterns in white sharks. These include coastal return migrations and the fastest known transoceanic return migration among swimming fauna, which provide direct evidence of a link between widely separated populations in South Africa and Australia. Transoceanic return migration involved a return to the original capture location, dives to depths of 980 meters, and the tolerance of water temperatures as low as 3.4 degrees C. These findings contradict previous ideas that female white sharks do not make transoceanic migrations, and they suggest natal homing behavior. 相似文献
98.
The full potential of organ transplantation has not yet been realized because of the hazards associated with the long-term use of immunosuppressive drugs. Modern research into mechanisms of immune tolerance offers the promise of reprogramming the immune system, so as to harness the body's natural tolerance mechanisms in the service of graft acceptance. This would allow the minimization of immunosuppressive treatment and offers the prospect of eventually weaning transplant recipients off their drugs. 相似文献
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Geebelen Wouter Vangronsveld Jaco Adriano Domy C. Carleer Robert Clijsters Herman 《Water, air, and soil pollution》2002,140(1-4):261-277
Lead immobilization was evaluated on soils spiked with increasingconcentrations of Pb (as Pb-acetate) using the following soilamendments: bentonite, zeolite, cyclonic ash, compost, lime,steelshot, and hydroxyapatite. The immobilization efficacy of theamendments was evaluated according to the following criteria:Ca(NO3)2-extractable Pb as an indicator of Pbphytoavailability, morphological and enzymatic parameters of beanplants (Phaseolus vulgaris) as indicator of phytotoxicity, and Pb concentration in edible tissue of lettuce (Lactuca sativa). The lowest reductions in Ca(NO3)2-extractablesoil Pb occurred when bentonite and steelshot were applied. Phytotoxicity from application of steelshot was confounded by toxic amounts of Fe and Mn released from the by-product which killed the lettuce seedlings. Addition of zeolite induced poorplant growth independent of Pb concentration due to its adverseeffect on soil structure. Substantial reductions in Ca(NO3)2-extractable Pb were observed when cyclonic ash, lime, compost and hydroxyapatite were applied. In general,these amendments reduced Pb phytotoxicity concomitant with reduced Pb concentration in lettuce tissue. Cyclonic ash, limeand compost further improved plant growth and reduced oxidativestress at low soil Pb concentrations due to soil pH increase mitigating Al or Mn toxicity. 相似文献