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1.
瘤胃中纤维物质降解规律的研究进展   总被引:1,自引:0,他引:1  
为了研究反刍动物瘤胃中饲料纤维物质的降解规律,采用文献资料研究法,分别从饲料纤维物质对反刍动物生产机能的影响、考量指标和影响瘤胃降解的因素三个方面,对饲料中纤维物质在反刍动物生产中的应用及其在瘤胃中降解规律的研究进展做综合论述。  相似文献   

2.
To establish a method for determining five saponins(notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1 and ammonium glycyrrhizinate) in Glycyrrhizae, Notoginseng and Ginseng, the high performance liquid chromatography with diode array detector(HPLC-DAD) method was applied to an Inertsil ODS-SP column(4.6 mm×250 mm, 5 μm) with a mobile phase consisting of acetonitrile-0.05% phosphoric acid in a gradient elution manner. The flow rate was 1.0 mL/min. The column temperature was 30 ℃ and the detection wavelengths were 203 nm and 237 nm, respectively. The linear ranges were 0.700,0—7.000,0 μg for R1(r=1.000,0), 0.751,1— 7.511,4 μg for Rg1(r=1.000,0), 0.677,2—6.771,6 μg for Re(r=1.000,0), 0.733,9—7.339,1 μg for Rb1(r= 1.000,0), and 0.540,0—5.399,8 μg for ammonium glycyrrhizinate(r=0.999,9), respectively. In addition, their average recoveries were 100.28%, 105.83%, 104.09%, 99.36% and 98.54%, respectively. The relative standard deviations(RSDs) of precision, reproducibility and recovery were all less than 1.5%. The results indicate that the method is simple, accurate and reproducible so that it can be used for the simultaneous determination of the five saponins in Chinese patent medicines containing the three kinds of herbs.  相似文献   

3.
INTRODUCTION Livestock is one of the largest sources of meth-ane emission with 80~115 million tons produced peryear, equivalent to 15%~20% of total anthropogenicmethane (IPCC, 2001). The global cattle population isresponsible for 73% of methane emissions of alllivestock, and methane produced during ruminalfermentation represents a loss of 2%~15% of grossenergy intake and may contribute to global warming(Johnson and Johnson, 1995). Many researches hadbeen carried out to find ways to low…  相似文献   

4.
本试验采用尼龙袋技术研究了用早灿稻谷替代玉米的肉牛饲粮中有机物在瘤胃中的降解规律,试验处理为早灿稻谷分别替代肉牛饲粮中0%、50%、75%、100%玉米四个替代水平的饲粮.结果表明:1、四组饲粮有机物动态降解率分别为69.87%、67.08%、63,89%和64.42%;2、随早灿稻谷替代水平的增高,有机物潜在的可消化组分比例不断降低; 3、各组饲粮有机物消失率观察值对动态消化模拟方程(P= a+ b-be-a)的拟合度高( R2=0.973~0.996).  相似文献   

5.
利用辉光放电等离子体技术降解橙黄G偶氮染料废水,借助紫外光谱分析了其降解过程,考察了多种因素对其降解效果的影响.结果表明,提高染料初始浓度和电解质浓度可提高橙黄G的降解率.改变溶液的初始pH值,橙黄G的降解率随溶液的初始pH值升高而增加.橙黄G降解60min后,无催化剂时,降解率达到71.68%;在催化剂Fe^2+和Mn^2+存在时降解率达到92.48%和89.69%,COD去除率为95.85%和63.44%;H2O2存在时,降解率达到78.91%.  相似文献   

6.
选取北京具有代表性的23个公园及生活小区作为采样区,研究各采样区中赤子爱胜蚓体内持久性有机氯农药滴滴涕(DDTs)和六六六(HCHs)的含量和来源.结果表明,赤子爱胜蚓体中的DDTs和HCHs总浓度分别为18.97—11129.75μg·kg^-1和0.65—44.78μg·kg^-1.赤子爱胜蚓体内存在较高浓度DDTs暗示其可能对公园的生态系统和食物链有潜在危害.根据DDTs各异构体含量特征比(p,p'-DDE/p.p'-DDT平均值:5.07;o,p'-DDT/p,p'-DDT 平均值:0.76)可以推断出部分园林环境中很可能有新的污染源存在.  相似文献   

7.
花粉中微量元素的ICP-MS法分析   总被引:3,自引:0,他引:3  
报道了采用微波消解法处理样品,运用电感耦合等离子体质谱法(ICP-MS)测定花粉中微量元素的方法.在优化实验条件下,方法的检出限为0.006 9~20.3μg/g,相对标准偏差为2.70%~9.86%,回收率为89.3%~109.6%.  相似文献   

8.
INTRODUCTION It was recognized that when animals are offereda low-nitrogen, high fibre roughage such as rice straw(RS), one of the critical nutrients is fermentable ni-trogen (N) available to rumen microbes (ARC, 1984). The use of urea/molasses blocks is a convenient way for avoiding excessive intake of urea, and will ensure an almost continuous supply of ammonia-N (Preston, 1986). Urea/molasses block feeding yielded positive results in many parts of the world (Kunju, 1986; Hadjipanay…  相似文献   

9.
建立测定芦荟中两种重要微量元素铁和锌含量的分光光度方法,考察了同一个芦荟样品中共同测定铁和锌的分光光度条件以及其他共存元素对测定的影响,确定了最佳测定条件.在最佳测定条件下,铁和锌的线性范围、回归方程、相对标准偏差、检测限和回收率分别为0.08~1.50μg/mL、0.01~0.50μg/mL;Y=0.019 53+0.179 64 X(r=0.999 94)、Y=0.008 89+0.561 38 X(r=0.997 37);4.37%、2.90%;0.03μg/mL、0.008μg/mL;99.0%~109.0%、98.0%~106.8%.分光光度法简便、快速、应用广泛,能够进行多元素的共同测定.  相似文献   

10.
哺乳动物排卵的过程包括:脑下垂体前叶分泌LH到体循环后,下丘脑脉冲性释放GnRH到垂体门脉系统.而LH峰介导了卵泡成熟、卵泡破裂和排出。哺乳动物根据引起下丘脑分泌GnRH方式的不同分为自发性排卵(人、羊、牛、马和猪等)和诱发性排卵(兔、貂、猫和骆驼等)动物,这其中自发性排卵动物具有一定的发情周期。早期研究发现交配过程能促发羊驼和驼马的排卵.最新研究发现精液中存在一种促排卵因子(OIF),这有助于了解自发性和诱发性排卵动物排卵的机制。OIF能刺激LH分泌、排卵和黄体腺的发育,并且通过体循环而非局部通路发挥作用。OIF是一种能耐热和抗蛋白酶K消化的蛋白质分子(分子团为14kDa),它可能是一种蛋白复合体或者激素原的一部分。OIF发挥作用是和剂量相关的。OIF已被证实存在于骆驼、牛、马、猪和袋熊等动物中。OIF在自发性排卵动物中能介导初情期小鼠促排、能改变母牛卵泡渡的动态变化、能提升LH的释放(体外培养大鼠、小鼠、豚鼠、兔、驼马和牛的脑下垂体细胞)。  相似文献   

11.
本文介绍了各类阳图PS版再生方法。通过对比表明,阳图PS版无损伤快速再生法,工艺简便可靠,成本低,质量好,投资小,效益高。  相似文献   

12.
Two isomers ofnitrochlorobenzene (o- andp-NCB) were treated by a Pd/Fe catalyst in aqueous solutions through catalytic amination and dechlorination. Nitrochlorobenzenes are rapidly converted to form chloroanilines (CAN) first through an amination process, and then rapidly dechlorinated to become aniline (AN) and CI^-, without the involvement of any other intermediate reaction products. The amination and dechlorination reaction are believed to take place predominantly on the surface site of the Pd/Fe catalysts. The dechlorination rate of the reductive degradation of the two isomers of nitrochlorobenzene (o-, and p-NCB) in the presence of Pd/Fe as a catalyst was measured experimentally. In all cases, the reaction rate constants were found to increase with the decrease in the Gibbs free energy (correlation with the activation energy) of NCBs formation; the activation energy of each dechlorination reaction was measured to be 95.83 and 77.05 kJ/mol, respectively for o- and p-NCB. The results demonstrated that p-NCBs were reduced more easily than o-NCBs.  相似文献   

13.
The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fen'aentation of cottonseed meal (CSM). Six groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. capsuligena ZD- 1, C. tropicalis ZD-3, S. cerevisae ZD-5, A. terricola ZD-6, A. oryzae ZD-7, or A. niger ZD-8. One not inoculated group (substrate) was used as a control. Levels of initial and final free gossypol (FG), crude protein (CP), amino acids (AA) and in vitro digestibility were assayed. The experiment was done in triplicate. The experimental results indicated that microbial fermentation could greatly decrease (P〈0.05) FG levels in CSM. The detoxification efficiency differed between the species of microorganisms applied. From the perspective of reducing CSM potential toxicity, C. tropicalis ZD-3 was most successful followed by S. cerevisae ZD-5 and A. niger ZD-8. They could reduce FG levels of CSM to 29.8, 63.07 and 81.50 mg/kg based on DM (dry matter), respectively, and their detoxification rates were 94.57%, 88.51% and 85.16%, respectively. If crude protein, amino acids content and their in vitro digestibility were also taken into account, Aniger ZD-8 may be the best choice. The CP content of CSM substrate fermented by C. tropicalis ZD-3 and A. niger ZD-8 were improved by 10.76% and 22.24%; the TAA (total amino acids) contents were increased by 7.06% and 11.46%, and the EAA (essential amino acids) were raised by 7.77% and 12.64%, respectively. Especially, the levels of methionine, lysine and threonine were improved greatly (P〈0.05). The in vitro CP digestibility of CSM fermented by C. tropicalis ZD-3 and A. niger ZD-8 was improved by 13.42% and 18.22%, the TAA were increased by 17.75% and 22.88%, and the EAA by 16.61% and 21.01%, respectively. In addition, the in vitro digestibility of methionine, lysine and threonine was also improved greatly (P〈0.05).  相似文献   

14.
研究在抗坏血酸-硫氰酸钾-醋酸-醋酸钠-吡啶-明胶的混合底液中,用单扫描示波极谱法连续测定10种中药材中的铅和锌,在该体系内样品中的铅和锌在滴汞电极上产生灵敏的还原波,峰电位分别为-0.456V(vs.SCE)和-1.038V(vs.SCE),铅的线性回归方程、相关系数和线性范围分别为:I=16.15 Cx-73.00,r=0.9996和0.005μg·mL^-1~0.15mg·ml^-1;锌的线性回归方程、相关系数和线性范围分别为:I=5.891Cx+1.641,r=0.9998和0.006μg·mL^-1~0.20mg·mL^-1(Cx:浓度,单位:μg·mL^-1),铅和锌的回收率分别为:95.2%~104.4%和95.2%~104.6%;铅和锌的相对标准偏差分别为:1.82%~4.97%和1.03%~4.60%,方法简单,快速,正确,结果令人满意.  相似文献   

15.
间接血凝试验(IHA)检测肝片形吸虫病的研究   总被引:2,自引:0,他引:2  
以肝片形吸虫成虫虫体制备的纯化抗原为诊断液,采用间接血凝试验(IHA)检测了40只山羊和160头牛血清,并与粪便检查法作平行试验。结果显示肝片形吸虫阳性检出率,IHA法为12.00%,粪便检查法为9.00%。与粪检结果相比,总的血清阳性符合率为62.50%,其中牛为57.14%,山羊为100.00%;总的血清阴性符合率为98.29%,其中牛为97.85%,山羊为100.00%。结论:IHA适合于大规模的血清流行病学调查,可以快速的筛选出大量的阴性样品。  相似文献   

16.
建立高效液相色谱法测定豆奶粉中三种异黄酮含量的测定方法。采用LC-20AT高效液相色谱系统,以甲醇-水(5.5:4.5)为流动相,检测波长为260 nm,流速为0.8 mL.min-1。待测组分与其他组分分离度良好,结果表明染料木苷、大豆黄素、染料木素线性范围分别为11.47~172μg.mL-1(r=0.9998),5.33~80μg.mL-1(r=0.9999),8.26~124μg.mL-1(r=0.9998),平均回收率分别为98.9%,98.7%,99.4%,相对标准偏差分别为0.3%,1.8%,2.0%。该方法准确且重现性好,结果可为不同人群选择豆类食品提供科学依据。  相似文献   

17.

Objective

Bovine endometritis is one of the most common reproductive disorders in cattle. The aim of this study was to investigate the anti-inflammation potential of punicalagin in lipopolysaccharide (LPS)-induced bovine endometrial epithelial cells (bEECs) and to uncover the underlying mechanisms.

Methods

bEECs were stimulated with different concentrations (1, 10, 30, 50, and 100 μg/ml) of LPS for 3, 6, 9, 12, and 18 h. MTT assay was used to assess cell viability and to identify the conditions for inflammatory injury and effective concentrations of punicalagin. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess gene expression of pro-inflammatory cytokines. Western blotting was used to assess levels of inflammation-related proteins.

Results

Treatment of bEECs with 30 μg/ml LPS for 12 h induced cell injury and reduced cell viability. Punicalagin (5, 10, or 20 μg/ml) pretreatment significantly decreased LPS-induced productions of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α (TNF-α) in bEECs. Molecular research showed that punicalagin inhibited the activation of the upstream mediator nuclear factor-κB (NF-κB) by suppressing the production of inhibitor κBα (IκBα) and phosphorylation of p65. Results also indicated that punicalagin can suppress the phosphorylation of mitogen-activated protein kinases (MAPKs) including p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK).

Conclusions

Punicalagin may attenuate LPS-induced inflammatory injury and provide a potential option for the treatment of dairy cows with Escherichia coli endometritis.
  相似文献   

18.
采用溶胶凝胶法合成纳米二氧化钛光催化剂,X衍射及红外表征显示银已进入催化剂晶胞中.以汞灯模拟紫外光,氙灯模拟自然条件下太阳光催化降解酸性红B染料,结果表明1%和2%银掺入提高了纳米二氧化钛的可见光催化效能,使得催化剂的吸光波长范围红移,X衍射表征及催化剂筛选实验表明2%Ag-TiO2为锐钛矿晶型,具有较高催化活性,常温常压500 w氙灯照射下,催化剂用量为1.5 g/L、模拟废水pH=4、光照150 min、模拟废水浓度为50 mg/L时,酸性红B染料模拟废水的脱色率达90%,矿化率达60%.  相似文献   

19.
INTRODUCTION The world population of buffaloes(Bubalus bubalis)has been estimated at over172million head,more than97%(167.6million)of which are in Asia and the Pacific region,mainly in India(97.7million)and Pakistan(25.5million)(FAO,2004).About98%of buffaloes in the region are raised by small farmers owning less than two hectares of land and less than five buffaloes(Mudgal,1992).In general,the water buffalo is regarded as more productive,healthier and more useful than the cow,especiall…  相似文献   

20.
壳聚糖对乳房炎奶牛血清胆固醇、尿酸和肌酐的影响   总被引:4,自引:0,他引:4  
为确定壳聚糖对奶牛乳房炎的治疗效果,选择产奶量、胎次和泌乳期相近,营养中等,乳房炎阴性奶牛6头,阳性30头,组成0(阴性对照组)、1(阳性对照组)和2、3、4、5组(试验组),每组6头.各组基础日粮和饲养管理相同.分别在基础日粮中添加壳聚糖0g、0g、10g、20g、40g和80g/d/头.连续喂养2周,分别与试验的0d、7d、14d采取血样,分离血清,测定血清中胆固醇、尿酸和肌酐的含量.结果:应用壳聚糖7~14d后,2、3、4、5组奶牛血清胆固醇含量均数有随壳聚糖用量的增加而降低的趋势,但差异不显著(P﹥0.05);血清尿酸和肌酐水平显著(P﹤0.05)或极显著(P﹤0.01)地降低.结论:壳聚糖具有加快乳房炎患牛机体对尿酸和肌酐排泄的功能,提高机体对炎症的抵抗力,促进机体的康复过程.  相似文献   

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