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25-羟胆钙化醇与维生素D_3对北京鸭生产性能和骨骼发育的影响 总被引:1,自引:0,他引:1
试验选用2 160羽1日龄北京鸭,按4×3两因素设计随机分成12个处理,每处理6个重复;分别饲喂不同水平的25-羟胆钙化醇(25-OH-D3)(0、35、70、105μg/kg)与维生素D3(2 500、3 000、3 500 IU/kg)的日粮,探讨25-OH-D3在肉鸭日粮中的使用效果。结果表明:不同水平25-OH-D3对北京鸭生产性能没有显著影响;添加105μg/kg较35、70μg/kg显著降低45日龄北京鸭胸肌率(P<0.05);70、105μg/kg 25-OH-D3较35μg/kg显著提高了胫骨磷含量(P<0.05)。添加3 500、3 000 IU/kg维生素D3较2 500 IU/kg显著提高15~35日龄北京鸭日增重(P<0.05);添加3 500 IU/kg维生素D3较3 000、2 500 IU/kg显著提高14、45日龄胫骨钙含量(P<0.05)。25-OH-D3和维生素D3对14日龄胫骨中钙、磷含量和45日龄胫骨磷含量分别存在极显著(P<0.01)和显著(P<0.05)地交互作用。综合本试验可得出,北京鸭日粮中添加3 000 IU/kg维生素D3和70μg/kg 25-OH-D3效果最佳。 相似文献
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Diethylphosphono acetic acid (DPA) was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method (AEM) or 1-ethyl-3-(3-dimethylaminopropyl)-carbodimide method (EDC). The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay (CI-ELISA). A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides. 相似文献
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Gundolf Kohlmaier Luita Kohlmaier Elke Fries Wolfgang Jaeschke 《European Journal of Forest Research》2008,127(2):133-147
With the analytical tool, Frankfurt Harvested Wood Products Model, FPM, the carbon stocks and carbon stock changes of Harvested
Wood Products, HWP, either in USE or in LANDFILLS L-F, have been evaluated, each separately, from the readily available statistical
data base of the FAO, FAOSTAT, on the wood commodities: “Sawnwood and Wood-based Panels, SWP” and the paper commodities, “Paper
and Paperboard, PAP”. The focus was on the newly founded Asia-Pacific Partnership countries for Clean Development and Climate
(in short AP6), including Canada, which wants to join the AP6, in relation to the countries of the European Union EU-25. It
could be shown that the stocks and stock changes of the HWP in USE follow a simple algorithm of the annual consumption or
production and their mean annual growth, for the categories SWP and PAP, provided the mean residence times of the HWP in USE
can be estimated. With the information on the fraction of residues entering the landfills and their estimated residence times
an equivalent simple expression has been derived for stocks and stock changes of the HWP in LANDFILLS L-F. Their values have
been calculated to be approximately 0.5 to 0.7 times smaller than those of the HWP in USE. Still, all stock changes of the
HWP in L-F were positive and thus accumulating carbon. However, when methane outgasing within the HWP in L-F had been considered,
the calculated Greenhouse Gas Balance was zero or negative under the estimated parameters thus to at least partly compensate
the positive storage of carbon in HWP in USE. The percentage of CO2 removed by the HWP in USE in comparison to the annual greenhouse gas emissions varied from 0.3 to 1.7%, with a mean value
of 0.8% for the AP6 countries including Canada, in contrast to 1.0% of the EU-25 countries. Despite of the relative small
magnitude in relation to the total emission of all GHG this contribution should not be neglected in the GHG Budget of a country. 相似文献
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为研究不同剂量25羟基维生素D3[25(OH)VD3]对断奶前犊牛血液水平、抗氧化能力和免疫功能的影响,选取18 头健康状况良好的新生荷斯坦犊牛,随机分成3 组,每组6 头进行为期56 天的饲养试验。分为对照组[不添加25(OH)VD3]、低剂量组[25(OH)VD3添加量6 000 IU/头·天]和高剂量组[25(OH)VD3添加量12 000 IU/头·天]。结果表明,与对照组相比,随着25(OH)VD3添加剂量增加,血浆生长激素、胰岛素样生长因子-1、过氧化氢酶、超氧化物歧化酶、总抗氧化能力以及免疫球蛋白G(IgG)含量显著增加(P<0.05),而丙二醛含量随剂量增加而存在降低趋势(P=0.079)。与对照组和低剂量组相比,高剂量组血浆免疫球蛋白A(IgA)含量有增加趋势(P=0.059)。综上所述,断奶前犊牛饲喂高剂量25(OH)VD3有利于促进体内生长激素和胰岛素样生长因子-1分泌,可提高犊牛抗氧化能力,增强免疫功能。 相似文献
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CDC25A, TSSK3 and P53 expressionsin vitro in cultured sertoli cells after FSH treatment were studied in order to provide some data for further researches of spermatogenesis. Different concentrations of... 相似文献