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91.
Moringa stem meal (MSM) with a high level of crude fibre (CF) might be developed and utilized in herbivorous geese as an unconventional feedstuff. The aim of this study was to investigate the effect of the MSM level in the diet on the growth performance, slaughter performance, breast meat quality and serum biochemical parameters in geese from 22 to 70 days of age. A one-factor completely randomized design was adopted in our study. A total of one thousand eight 21-day-old geese were randomly divided into six groups, with six replicates per group and 28 birds per replicate. The geese were fed diets containing MSM levels of 0, 20, 40, 60, 80 or 100 g/kg during day 22–70. The dietary MSM level had no effect (p > .05) on the final body weight (BW), average daily gain (ADG) or average daily feed intake (ADFI). The feed/gain ratio (F/G) increased linearly (p < .001) as the dietary MSM level increased. No differences (p > .05) were observed in the slaughter performance, meat quality and the relative organ weight (except for thymus) of the geese (p > .05). The relative weight of the thymus in the geese fed diets with supplementation of MSM was higher than that in the non-supplemented MSM control group (p < .05). In addition, 100 g MSM/kg of diet decreased the serum glucose (GLU) level (p < .05) and increased the alanine transaminase (ALT) enzyme activity (p = .03). Dietary MSM levels of no more than 60 g/kg had no effects on the growth performance and slaughter performance, whereas diets with 100 g MSM/kg increased the F/G and serum ALT enzyme activity, as well as decreasing the serum GLU level. Therefore, MSM provided at a reasonable level could be developed as an unconventional feedstuff for geese at the finisher period.  相似文献   
92.
现行国际主权信用评级呈现出明显的顺周期特征而广受诟病。在对评级指标体系优化的基础上,采用90个主权国家2005~2012年经济数据进行面板随机效应和门限效应回归,对主权信用评级决定模型进行估计,运用欧债危机发生前后的数据进行模拟评级,结果表明:优化后的指标体系显示出较好的逆周期特征。  相似文献   
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94.
合理的产业结构会带动经济的快速发展,促进自然资源的合理利用,对于保持生态平衡有非常大的推动作用。文章在我省现有林业产业结构分析的基础上,通过建立林业产业园区,发展林下经济以及大力发展旅游及其相关产业的林业产业结构调整对策。  相似文献   
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96.
Nitrofurans are broad-spectrum antibiotics which have been widely used in food animals to the prevention and treatment of gastrointestinal infections.Due to abuse of drugs by criminals,animals could produce drug-resistant strains,which reduces the role of antibiotics.Meanwhile,excessive drugs residues in food has carcinogenic,teratogenic and mutagenic effects to the human body.In this paper,the damage and the detection methods of the residues of the nitrofurans in food are surveyed.The main detection methods include high performance liquid chromatography,liquid chromatography-mass spectrometry,liquid chromatography tandem mass spectrometry,enzyme-linked immunoassay,colloidal gold immunoassay and fluorescence immunity analysis method.The research status of various detection methods are summarized and the suggestions for further research are put forward.It is expected to provide reference for future research.  相似文献   
97.
A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.  相似文献   
98.
以嘉氏羊蹄甲(Bauhinia galpinii)种子为材料,开展了不同浸种催芽处理对比试验。结果表 明,相比不浸种处理,3 个浸种处理明显提高嘉氏羊蹄甲的种子发芽势和发芽率,平均苗高也明显高于不 浸种组,其中,温水(60 ℃ ) 浸种6 h 组嘉氏羊蹄甲种子发芽率最高,达74.7%,苗高生长最快。  相似文献   
99.
100.
剑麻是一种广泛使用的硬质纤维的主要来源,被广泛的运用到各种行业,需求极大;但其收割现以手工为主,且因剑麻自身带有刺,加大了收割的难度,降低了效率。为解决剑麻的纯手工收割收割困难以及效率低的问题,提出一种多自由度剑麻收割机的机械,并申请了国家发明专利,得到授权。本文将运用UG、Sdams以及Mat Leb对该机械进行改进设计与仿真分析,并试制实物机械进行试验。试验结果表明:该机实现了剑麻收割的半自动化并提高剑麻收割的效率,可满足现行各行各业对剑麻的需求量。  相似文献   
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