单宁和氧化锌组合对断奶仔猪粪便菌群、血清抗氧化及肝脏功能指标的影响

本试验旨在研究单宁和氧化锌不同水平组合对断奶仔猪粪便菌群及血清免疫、抗氧化和肝脏功能相关血液生化指标的影响。选用体重相近,25日龄杜×长×大断奶仔猪270头,随机分成9组,每组3个重复,每个重复10头猪。对照组饲喂基础日粮加高锌（3 000 mg/kg氧化锌）的日粮,试验1~8组（T1~T8）分别饲喂基础日粮添加以下氧化锌与单宁组合的日粮：（2 000+0）、（2 000+1 000）、（1 000+0）、（1 000+1 000）、（1 000+1 500）、（1 000+2 000）、（0+1 500）、（0+2 000） mg/kg。试验期30 d。分别于试验的第14与28天采集仔猪新鲜粪样,测定粪便中各细菌的数量。试验结束采集血样,测定血清免疫、抗氧化及肝脏功能相关指标。结果显示,试验第14天,各组断奶仔猪粪便大肠杆菌、乳酸菌和双歧杆菌数量均无显著差异（P>0.05）。试验第28天,T1、T6组断奶仔猪粪便乳酸菌数量极显著高于对照组（P<0.01）,而双歧杆菌数量则显著高于对照组（P<0.05）,但各组大肠杆菌数量均无显著差异（P>0.05）。各组断奶仔猪血清中IgG和IgA含量、MDA含量及GSH-Px活力均无显著差异（P>0.05）。但T5、T6、T7、T8组断奶仔猪血清GSH含量极显著高于对照组（P<0.01）。除了T2和T5组,其余各组猪血清谷草转氨酶活性均显著或极显著低于高锌对照组（P<0.05;P<0.01）。本试验结果表明,与单一使用高剂量氧化锌相比,单宁与氧化锌适量水平组合有利于乳酸菌及双歧杆菌的增殖、提高断奶仔猪抗氧化能力并对肝脏产生保护作用。     

水稻锌营养高效基因型的生理特性

采用HEDTA螯合缓冲营养液培养法,研究了水稻锌营养高效基因型IR34、IR36、IR8192和锌敏感基因型IR26、测64 7、碧玉早糯在不同锌离子活度（pZn2+>11.5,11.3, 11.0, 10.6, 10.3, 9.7）下的生理特性。结果表明,锌离子活度在对不同水稻基因型秧苗生理特性影响上有明显的区别,其中叶绿素含量、光合速率、MDA含量和根系H+分泌量差异比较明显。在供锌水平较低情况下,水稻锌营养高效基因型叶绿素含量下降速度慢,光合速率降低幅度小,MDA含量升高的幅度小,根系能分泌更多的H+,这些指标可以作为衡量水稻锌营养效率的指标。     

日粮中锌水平对妊娠母猪繁殖性能的影响

试验研究了不同日粮锌水平对母猪繁殖性能、母猪和新生仔猪血清参数等指标的影响。结果表明 ,日粮中添加5 0 mg/ kg锌足以防止母猪出现锌缺乏症。添加 75、10 0、12 5 mg/ kg锌组产活仔数可提高 0 .5、1.0 (P<0 .0 5 )、0 .87(P<0 .0 5 )头 /胎 ,平均初生重可提高 4 .73%、7.4 3% (P<0 .0 5 )和 9.4 6 % (P<0 .0 5 ) ;平均初生窝重可提高 6 .38%、18.5 8% (P<0 .0 5 )、19.2 8% (P<0 .0 5 )。适量增加妊娠母猪日粮中锌含量可提高母猪血清孕酮含量 ,提高新生仔猪血清白蛋白水平 ,降低血清中尿素氮含量 ,提高新生仔猪血清 T3、GH和 IGF- 1水平 ,增加新生仔猪血液和肝脏中锌含量     

施锌对盐碱地玉米生理特性及籽粒锌含量的影响

为研究不同施锌水平对盐碱地玉米生理特性及籽粒锌含量的影响,以科河699为供试材料,采用随机区组设计进行田间试验,根据不同施锌肥方式设置6个处理：T0(0 kg·hm^-2)、T1(7.5 kg·hm^-2)、T2(15 kg·hm^-2)、T3(22.5 kg·hm^-2)、T4(30 kg·hm^-2)、T5(37.5 kg·hm^-2),测定不同处理下玉米生理特性、籽粒锌含量及产量。结果表明,施锌降低了盐碱地玉米叶片相对电导率、脯氨酸含量、丙二醛含量,灌浆期T3处理的叶片相对电导率、脯氨酸含量、丙二醛含量分别较T0处理降低了22.3%、24.7%、15.9%;施锌提高了玉米叶片保护性酶活性,大喇叭口期T3处理的超化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)活性分别较T0处理提高了68.7%、152.1%和72.6%;同时,玉米籽粒锌含量和产量随施锌量的增加呈先增加...     

长株潭地区5种母质发育水稻土锌和铜及镍元素剖面分布特征

以长株潭地区5种母质发育的水稻土,即河沙泥、红黄泥、黄泥田、麻沙泥和紫泥田为研究对象,按土壤系统分类原则挖掘典型剖面24个及剖面土样137个,分析测定了土壤全量和有效态铜、锌、镍含量以及土壤pH值、颗粒分级组成、有机质、游离氧化铁含量,研究水稻土铜、锌、镍元素的剖面分布特征以及与土壤理化性质之间的关系。结果表明:剖面各层土壤全铜、全锌含量平均值随剖面加深逐渐降低,耕作层、犁底层、底土层全铜含量分别为26.82、21.54、18.54 mg/kg,全锌含量分别为75.84、66.00、63.19 mg/kg,全镍含量分别为18.40、17.50、18.23 mg/kg;土壤铜、锌、镍有效态含量平均值随剖面加深均逐渐降低,耕作层、犁底层、底土层有效铜含量分别为4.04、2.99、1.29 mg/kg,有效锌含量分别为4.77、2.76、1.14 mg/kg,有效镍含量分别为0.54、0.44、0.23mg/kg;黄泥田的全量和有效态铜、锌、镍含量均较高,麻沙泥的较低;土壤有机质含量是决定土壤有效态铜、锌、镍含量的主要因子,土壤游离氧化铁含量是决定土壤全铜、全镍含量的主要因子,全锌含量与土壤pH值、颗粒分级组成、有机质、游离氧化铁含量均无显著相关性。总体上,长株潭地区水稻土0～25 cm土体以及部分剖面土壤全层有效态铜和锌含量高于临界值(铜1.5 mg/kg、锌0.5 mg/kg),呈盈余状态,可满足浅根或中根作物对铜、锌的需求。     

固始鸡孵化期间蛋黄胆固醇、粗脂肪和锌含量分析

对固始鸡种蛋孵化期间蛋黄中胆固醇、粗脂肪和锌含量的测定表明,胆固醇含量0～6胚龄明显升高,以后出现阶段性降低;粗脂肪含量0～6胚龄无明显变化,6胚龄以后逐渐降低;锌含量0～3胚龄和6～12胚龄明显升高,3～6胚龄和12～21胚龄降低.     

Enhancing the mineral and vitamin content of wheat and maize through plant breeding

More than half of the world's population suffers micronutrient undernourishment. The main sources of vitamins and minerals (iron, zinc, and vitamin A) for low-income rural and urban populations are staple foods of plant origin that often contain low levels or low bioavailability of these micronutrients. Biofortification aims to develop micronutrient-enhanced crop varieties through conventional plant breeding. HarvestPlus, the CGIAR's biofortification initiative, seeks to breed and disseminate crop varieties with enhanced micronutrient content that can improve the nutrition of the “hard to reach” (by fortification or supplementation programmes) rural and urban poor in targeted countries/regions. In attempting to enhance micronutrient levels in maize and wheat through conventional plant breeding, it is important to identify genetic resources with high levels of the targeted micronutrients, to consider the heritability of the targeted traits, to explore the availability of high throughput screening tools and to gain a better understanding of genotype by environment interactions. Biofortified maize and wheat varieties must have the trait combinations which encourage adoption such as high yield potential, disease resistance, and consumer acceptability. When defining breeding strategies and targeting micronutrient levels, researchers need to consider the desired micronutrient increases, food intake and retention and bioavailability as they relate to food processing, anti-nutritional factors and promoters. Finally, ex ante studies are required to quantify the burden of micronutrient deficiency and the potential of biofortification to achieve a significant improvement in human micronutrient status in the deficient target population in order to determine whether a biofortification program is cost-effective.     

Mycorrhizal (Rhizophagus Intraradices) Symbiosis and Fe and Zn Availability in Calcareous Soil

Greenhouse experiment was conducted to assess the iron (Fe) and zinc (Zn) fractionation patterns in soils of arbuscular mycorrhizal (AM) fungus-inoculated and uninoculated maize plants fertilized with varying levels of Fe and Zn. Soil samples were collected for Fe and Zn fractions and available Fe, Zn and phosphorus (P) contents besides organic and biomass carbon (BMC), soil enzymes and glomalin. Major portion of Fe and Zn fractionations was found to occur in the residual form. Mycorrhizal symbiosis increased the organically bound forms of Fe and Zn while reducing the crystalline oxide, residual Fe and Zn fractions, indicating the transformation of unavailable forms into available forms. Soil enzymes, viz. dehydrogenase and acid phosphatase activities in M+ soils, were significantly higher than M? soil consistently. Overall, the data suggest that mycorrhizal symbiosis enhanced the availability of Fe and Zn as a result of preferential fractionation and biochemical changes that may alleviate micronutrient deficiencies in calcareous soil.

Abbreviations: AM: arbuscular mycorrhiza; Fe: Iron; Zn: Zinc; P: Phosphorous; Amox-Zn: amorphous oxide bound zinc; Cryox-Zn: crystalline oxide bound zinc; DAS: days after sowing; DTPA: diethylene Triamine Penta Acetic Acid; MnO₂-Zn: manganese oxide bound zinc; OC-Zn: organically bound zinc; WSEX: water soluble plus exchangeable zinc; MnO₂ Fe: manganese oxide bound iron; OC-Fe: Organically bound iron; WSEX Fe: water soluble plus exchangeable iron.     

土壤中施加锌对豌豆(Pisum sativum L.)中锌浓度以及其种子产量的影响

A 2-year field experiment was conducted to assess the effect of applied zinc（Zn） on the seed yield of pea（Pisum sativum L.） and to determine the internal Zn requirement of pea with emphasis on the seed and leaves as index tissues.The experiment was carried out at two different locations（Talagang,Chakwal district and National Agricultural Research Centre（NARC）,Islamabad） in the Potohar Plateau,Pakistan by growing three pea cultivars（Green feast,Climax,and Meteor）.The soils were fertilized with 0,2,4,8,and 16 kg Zn ha^-1 along with recommended basal fertilization of nitrogen（N）,phosphorus（P）,potassium（K）,and boron（B）.Zinc application increased seed yield significantly for all the three cultivars.Maximum increase in the pea seed yield（2-year mean） was21%and 15%for Green feast,28%and 21%for Climax,and 34%and 26%for Meteor at Talagang and NARC,respectively.In all cultivars,Zn concentrations in leaves and seed increased to varying extents as a result of Zn application.Fertiliser Zn requirement for near-maximum seed yield varied from 3.2 to 5.3 kg ha^-1 for different cultivars.Zinc concentrations of leaves and seeds appeared to be a good indicator of soil Zn availability.The critical Zn concentration range sufficient for 95%maximum yield（internal Zn requirement）was 42-53 mg kg^-1 in the pea leaves and 45-60 mg kg^-1 in the seeds of the three pea cultivars studied.