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141.
142.
本文研究了4例患白肌病(WMD)绵羔羊体内VE、Se与谷胱甘肽过氧化物酶(GSH-Px)活性的关系。结果表明,4例羔羊血Se含量低达0.015μg/kg,且其含量与GSH-Px活性呈正相关(p<0.001);患羊主要组织器官中Se含量低于对照组(尤在肝脏低于0.05μg/kg);血清VE正常,而组织器官中α-VE很低。饲料中Se低于0.05μg/kg,α-VE更低 相似文献
143.
本文研究了4例患白肌病(WMD)绵羔羊体内VE、Se与谷胱甘肽过氧化物酶(GSH-Px)活性的关系。结果表明,4例羔羊血Se含量低达0.015μg/kg,且其含量与GSH-Px活性呈正相关(p<0.001);患羊主要组织器官中Se含量低于对照组(尤在肝脏低于0.05μg/kg);血清VE正常,而组织器官中α-VE很低。饲料中Se低于0.05μg/kg,α-VE更低 相似文献
144.
Lianhe Zhang Weiming Shi Xiaochang Wang Xinbin Zhou 《Journal of plant nutrition》2013,36(9):1601-1618
The paper deals with the selenium (Se) accumulation of different genotypes of rice (Oryza sativa Japonica) seedlings at early growth stage and its correlation with the Se content in grains in 151 rice varieties. A field trial showed the Se content in brown rice to range from 29 μg/kg to 103 μg/kg. The results from hydroponic culture with representative varieties of high-, moderate- and low-Se content showed that total Se values for the high-Se genotypes were markedly higher than those of the low-Se varieties. This was true of Se content of the whole plant, Se content of shoots, biomass of shoots, and rate of Se accumulation in shoots. There were, however, no significant differences in values for total Se in roots, rate of accumulation in roots, and biomass of roots between high- and low-Se groups. Selenium content in brown rice was positively correlated with the total Se of the whole plant, shoot, and biomass of shoots. We concluded that the total Se transported from roots to shoots was more important than other factors in Se accumulation and content in brown rice. 相似文献
145.
Barbara Hawrylak-Nowak 《Journal of plant nutrition》2013,36(7):1232-1242
The aim of this experiment was to examine the effect of exogenous selenium (Se) on anthocyanin and chlorophyll accumulation, Se content, as well as the growth of maize (Zea mays var. ‘saccharata Kcke’) cv. ‘Zlota Karlowa’ seedlings. Plants were grown hydroponically in Hoagland's nutrient solution at different pH values: 4.5, 6.2, and 7.5. Selenium was added to the solution as either selenate (Na2SeO4) or selenomethionine (C5H11NO2Se) to a final concentration of: 0 (control), 5, 25, 50, and 100 μ M Se. Generally, the presence of Se in the medium caused an increase in the anthocyanin content and a simultaneous decrease of the total chlorophyll concentration depending on the Se form and dosage. Higher concentrations of anthocyanin were detected in the presence of selenomethionine than selenate, notably at pH 4.5. The effect of individual Se forms on maize seedlings, expressed on the basis of the fresh weight, indicate that selenomethionine was more phytotoxic than selenate. Selenium content both in roots and shoots increased linearly with increasing Se concentration in solution culture. However, a much higher Se level was found in the maize organs when plants were supplied with selenomethionine than selenate. Experimental evidence shows that the changes in anthocyanin content can be used as a test parameter reflecting the degree of Se toxicity in maize plants, and may be potential useful for bioindication of Se phytotoxicity in other higher plants. 相似文献
146.
AbstractTo evaluate labile selenium (Se) content in agricultural soils in Japan and to investigate its determining factors, 178 soil samples were collected from the surface layer of paddy or upland fields in Japan and their soluble Se contents were determined. Two grams of soil was extracted with 20 mL of 0.1 mol L?1 sodium sulfate (Na2SO4) solution for 30 min in boiling water, and the released Se was reduced to Se (IV) after organic matter decomposition. The concentration of Se (IV) was then determined by high performance liquid chromatography (HPLC) with a fluorescence detector after treatment with 2,3-diaminonaphthalene (DAN) and extraction with cyclohexane. Soluble Se content ranged from 2.5 to 44.5 μg kg?1 with geometric and arithmetic means of 11.4 and 12.8 μg kg?1, respectively, and corresponded to 3.2% of the total Se on average. The overall data showed log-normal distribution. In terms of soil type, Non-allophanic Andosols and Volcanogenous Regosols had relatively high soluble Se content, and Wet Andosols and Lowland Paddy soils had relatively low soluble Se content. In terms of land use, upland soils had significantly higher soluble Se content than paddy soils (p < 0.01). The soluble Se content had significant positive correlation with total organic carbon (TOC) content of the extract, soil pH and total Se content (p < 0.01). In conclusion, total Se content in combination with soil pH was the main determining factor of the soluble Se content of agricultural soils in Japan. 相似文献
147.
我国天然低硒饲料对畜禽生产、健康与疾病的影响 总被引:1,自引:0,他引:1
应用我国天然缺硒饲料,在实验室条件下进行了猪、鸡和鸭的缺硒模型试验研究。结果表明:饲料缺硒可导致生产中畜禽发生一系列表现在不同部位、不同程度的病理变化和临床症状。用缺硒饲料喂仔猪8周、雏鸡2周后,血液及组织中含硒量与GSH-Px活性显著降到较低值,并趋于稳定,这与动物开始出现缺硒症状的结果一致。鸡试验证明,缺硒日粮中补加100mg/kg维生素E或补加0.05ppm以上的硒,可防止鸡发生渗出性素质病。但仅补维生素E不能防止鸡胰脏的缺硒病变,还需同时补硒。对鸡胰脏中Cu、Zn、Mn等含量的测定结果表明,缺硒使胰脏变性,导致Cu、 Zn、Mn代谢障碍及含量下降(P<0.05)。试验还证明,增加日粮中蛋白质水平可加剧缺硒状况对畜禽的危害程度,说明对饲料条件较好,生长较快的畜禽品种,特别是幼畜、幼禽,应适当提高硒的需要量。 相似文献
148.
不同施硒方式对糜子产量及相关性状的影响 总被引:1,自引:0,他引:1
叶面喷施硒肥可以明显提高糜子籽粒中硒含量,但不同糜子品种富硒能力具有一定差异。60 g/hm2处理的糜子籽粒中硒含量为0.04~0.32 mg/kg,比对照平均增加了13.5倍;120 g/hm2处理的糜子籽粒中硒含量为0.07~0.46 mg/kg,比对照平均增加了19.4倍;180 g/hm2处理的糜子籽粒中硒含量为0.13~0.57 mg/kg,比对照平均增加了21.8倍;叶面喷施硒肥对糜子产量的影响不明显,对相同处理的不同糜子品种的产量有影响;叶面喷施硒肥能使多数糜子品种籽粒的蛋白质含量略有增加。 相似文献
149.
低硒土壤中不同主栽大豆品种积累硒的差异及其原因 总被引:1,自引:1,他引:1
通过大田和盆栽试验研究了低硒土壤中主栽大豆品种积累硒的品种差异并对其机理进行了初步探讨。结果表明 ,无论施硒与不施硒 ,不同大豆品种子粒对硒的积累均存在显著的差异。供试品种中 ,通矮 4 0 5积累土壤硒的能力较强 ,启东绿皮黄豆硒肥的肥效较高。盆栽试验结果表明 ,两品种子粒积累硒的差异是由于植株对土壤有效硒利用率的不同造成的。在硒酸钠依时间和浓度的吸收动态试验中 ,通矮 4 0 5幼苗含硒量均高于启东绿皮黄豆 ,但硒从根部向地上部的运输则无差异。说明通矮 4 0 5植株对土壤溶液中Se6 +较强的吸收能力导致了其对低硒土壤中有效硒有较高的利用率 ,是其子粒积累硒能力较强的根本原因。 相似文献
150.
选用5岁、平均体重为500 kg的西门塔尔阉牛3头,以玉米青贮和精料补充料为基础饲粮,采用3×3拉丁方设计,在饲粮中分别添加硒0.1、0.2和0.3 mg· kg-1和维生素E 30、60和90 U.kg-1,共9组,硒水平(mg·kg-1)/维生素E水平(U·kg-1)分别为0.1/30(1组)、0.2/30(2组)、0.3/30(3组)、0.1/60(4组)、0.2/60(5组)、0.3/60(6组)、0.1/90(7组)、0.2/90(8组)、0.3/90(9组),研究在饲粮中添加不同水平的硒对维生素E表观消化率的影响.结果表明,处理8和9组极显著高于2和4组(P<0.01),显著高于1、3、5和7组(P<0.05);1、3、5、6和7组显著高于2和4组(P<0.05).3、6和7组的GOT活性显著高于其余组(P<0.05).3和6组的GPT活性极显著高于1组(P<0.01),显著高于2、4、5、7、8和9组(P<0.05);2、4、5、7、8和9组显著高于1组(P<0.05).3、6和9组的GSH-Px活性极显著高于1、4和5组(P<0.01),显著高于2、7和8组(P<0.05);2、7和8组显著高于1、4和5组(P<0.05).研究表明,不同硒水平极显著影响牛维生素E消化率. 相似文献