Effect of feeding different levels of wheat roti on nutrient utilization and blood metabolite profile in semi‐captive Asian elephants (Elephas maximus)

This experiment was conducted to study the effect of different levels of wheat roti (WR) on nutrient utilization and blood metabolites in Asian elephants fed roughages ad libitum. Nine (3 M, 6 F) Asian elephants (14–52 years of age, 1909–3968 kg BW) were used in an experiment based on replicated Latin square design. Animals in each group (n = 3) were assigned to one of the three dietary treatments in a manner that animals in all the three groups were exposed to all the three treatments in three different periods. Each feeding trial comprised 30 days (25 days of adaptation and 5 days collection period). The amount of WR fed to the elephants was 0.18, 0.12 and 0.06% of BW in groups I, II and III, respectively. They were allowed to forage in the nearby forests for 6 h/day and to bathe for 2 h/day. The animals had ad libitum access to cut Rohini (Mallotus philippensis) trees in their night shelter. Intake and apparent digestibility of dry matter (DM), crude protein (CP), gross energy (GE), Ca, P, Fe, Cu and Zn were measured. Feed consumption was not significantly different among the groups. Significant (p < 0.01) decrease in digestibility of DM and GE and blood glucose concentration was observed with decreased level of WR in the diet. Feeding of WR at 0.06% of BW supplied adequate amount of DE, CP, Ca, P, Fe, Cu and Zn to meet requirement for adult maintenance. Feeding of WR in excess of 0.06% of BW supplied DE in excess of requirement, increased blood glucose concentration which may cause obesity and other associated health problems. It was concluded that the amount of WR should be restricted to 0.06% of BW in the diet of captive Asian elephants.     

Lentivirus-mediated calcitonin gene-related peptide transfection enhances endothelial differentiation of rat bone marrow mesenchymal stem cells

AIM：To study the effect of calcitonin gene-related peptide (CGRP) gene transfection mediated by lentivirus on the differentiation of rat bone marrow mesenchymal stem cells (MSCs) to endothelial cells. METHODS：Rat bone marrow MSCs were isolated by density gradient centrifugation combined with adherence method. Recombinant lentivirus vector carrying CGRP gene (Lenti-CGRP) was transfected into the MSCs. The secretion of CGRP in culture supernatants of the transfected MSCs was detected using ELISA method. The cells at passage 3 were divided into three groups: CGRP group (MSCs transfected with Lenti-CGRP), CGRP+CGRP8-37 (an antagonist of CGRP receptor) group and control group (MSCs transfected with PBS). The differentiation of the MSCs was detected by immunocytochemical staining for CD31 and factor Ⅷ-related antigen. The proliferation of the cells was measured by cell counting, and the angiogenic ability of the cells was analyzed using Matrigel assay. RESULTS：The proportion of CD31-and factor Ⅷ-related antigen-positive cells in CGRP and CGRP+CGRP8-37 groups was larger than that in control group (P<0.05). The numbers of the cells in CGRP and CGRP+CGRP8-37 groups were significantly increased compared with control group (P<0.05). Lumen-like structures were observed in CGRP and CGRP+CGRP8-37 groups. The above indexes in CGRP+CGRP8-37 group were reduced compared with CGRP group. CONCLUSION: Transfection with CGRP gene induces rat bone marrow MSCs to differentiate into endothelial cells and enhances their proliferation, suggesting that CGRP may play a role in the regulation of angiogenesis.     

菊花白锈病研究进展

菊花白锈病(Puccinia horiana Henn.)是菊花重要的流行性病害,也是多国检疫性病害,在经济上给切花菊生产造成重大损失,且有逐年加重的趋势.切花菊产业化生产刚刚在我国兴起,国内对菊花白锈病发生危害以及防治技术了解较少.现首次系统介绍国内外菊花白锈病的分布与为害、发病规律和防治技术等方面的研究进展,为我国菊花白锈病的研究和防治提供参考.同时探讨了菊花抗病研究的发展方向和策略.     

生物炭对不同水氮条件下小麦产量的影响

研究生物炭与氮肥互作在不同水分条件下对小麦关键生育期旗叶光合参数、产量与主要农艺性状的影响,探讨生物炭改良不同水肥条件土壤并提高其作物产量的效果与内在机理,可为农田有机物资源合理利用提供理论支撑。本研究采用盆栽试验,生物炭用量设置五个水平(0,1%,2%,4%和6%),氮肥设置N0,N1和N2(0,0.2 g·kg~(-1)和0.4 g·kg~(-1))三个水平,小麦拔节期控制土壤田间持水量的80%和50%模拟正常水分和干旱胁迫两种水分环境。于小麦拔节期和抽穗期测定旗叶光合参数和SPAD值,成熟后对小麦籽粒产量及主要农艺性状进行统计。结果显示:(1)与不施生物炭处理相比,1%和2%生物炭用量平均增产6.62%和11.01%,4%和6%生物炭用量平均减产6.88%和10.1%,同时会导致千粒重、穗粒数和株高的降低;(2)正常水分条件下,1%和2%生物炭用量与N1和N2之间存在协同增产作用,而4%和6%生物炭用量表现出负面效应;(3)干旱胁迫条件下,仅1%和2%生物炭用量与N1存在协同增产作用,生物炭处理削弱N2增产潜力;(4)N0水平下,生物炭处理均表现出促进小麦旗叶光合速率,增加产量的作用;(5)N1条件下,生物炭促进小麦旗叶光合速率且在干旱胁迫条件下效果更明显。总体上生物炭对小麦旗叶光合参数和产量的影响受生物炭用量、氮素水平和水分条件共同制约且存在复杂的交互作用,干旱会限制生物炭与氮肥的协同增产作用;在低肥力土壤上应用生物炭的增产效果较好,而在质地较细且肥力中等的土壤应用时推荐48 t·hm~(-2)(2%)生物炭用量。     

河套灌区春小麦高产栽培水氮高效利用研究

在内蒙古河套灌区解放闸灌域沙壕渠实验站,通过田间试验,对节水灌溉模式(拔节+抽穗2水)和常规充分灌溉模式(分蘖+拔节+抽穗+灌浆4水)下,不同施氮量对春小麦产量形成、水分利用和氮素利用等方面进行了研究.结果表明:2水与4水处理间小麦产量及其构成因素均无显著差异,而水分利用效率(WUE)比4水处理提高7.8%.在较低施氮...     

70%吡虫啉水分散粒剂(艾美乐)防治小麦穗蚜药效试验

试验结果表明,70%吡虫啉水分散粒剂（艾美乐）在4～5g/667m^2的剂量下,对小麦穗蚜的防治效果优良,药后1～21d的防效均在91%以上,兼有持效性较长、对小麦安全、对环境友好及使用方便等优点,是防治小麦穗蚜的较好药剂.     

黄粉虫、小麦胚芽对初产蛋鸡生产性能、蛋品质和抗氧化机能的影响

试验旨在研究饲粮中添加黄粉虫、小麦胚芽对初产蛋鸡生产性能、蛋品质、蛋黄和血清抗氧化指标的影响.选用20周龄产蛋率基本一致且健康的京红蛋鸡560只,随机分为7组,每组4个重复,每个重复20只鸡;采用双因子试验设计,3个黄粉虫水平(0.5％、1.0％、2.0％)×2个小麦胚芽水平(1％、2％).试验期为8周,其中预试期1周...     

外源甜菜碱对作物的抗旱作用效果研究

通过小麦浸种、水培、大面积喷施和茄子盆栽试验,研究了不同浓度外源甜菜碱对作物的抗旱作用效果。结果表明:外源甜菜碱浓度为25～50mg/L时可促进小麦种子发芽,光合作用强度[达7.07～7.57μmol/(s·m~2)]及生物学产量增加;在外源甜菜碱浓度100 mg/L时小麦幼苗叶片硝酸还原酶活性最高,达到35.23μg/(g·h),同时小麦抗旱性增强。数学模式寻优结果表明:在外源甜菜碱浓度26.4～68.9mg/L,土壤水分含量12.6％～20.7％时,可获得最佳的茄子生物总量。     

郭予元院士在宁夏植保防控事业中的学术贡献——纪念郭予元院士诞辰90周年

五六十年代的宁夏, 农业发展落后, 农业科学发展刚刚起步, 引黄灌区的水稻和南部西海固地区的冬小麦分别是当地的主要粮食作物, 其产量直接关乎当地群众温饱。但是由于特殊的地理位置和气候特点, 这些地区病虫害发生严重, 制约了当地的粮食生产。本文回顾了郭予元院士在宁夏进行病虫害科学研究, 为水稻稻瘟病、小麦麦种蝇和小麦腥黑穗病的监测预警, 防治示范做出的突出贡献。郭予元院士建立的预测预报体系及防治技术示范一直指导当地的农业生产, 并给全国的病虫害防治做了示范。     

保护性耕作下小麦和豌豆投入产出能值分析

应用能值分析的基本理论和方法,探讨了传统耕作(T)、免耕(NT)、传统耕作+秸秆还田(TS)、免耕+秸秆覆盖(NTS)、传统耕作+地膜覆盖(TP)、免耕+地膜覆盖(NTP)等不同耕作模式下小麦和豌豆的投入产出能值,测算了其净能值产出率、能值投入率、宏观经济价值。结果表明:同一耕作方式下,种植小麦能值投入大于豌豆,豌豆能值产出是小麦的5倍以上,且豌豆宏观经济价值远远大于小麦;不同耕作方式下,两种作物净能值产出率均为免耕处理大于相应的耕作处理;由于传统耕作的三种模式人工和机械费用的投入远高于免耕三种模式,使得耕作处理下能值总投入大于相应的免耕处理;免耕+秸秆覆盖处理下,小麦和豌豆净能值产出率和宏观经济价值均达到最大,分别达到了0.64、3.93和9.26、53.1。说明免耕+秸秆覆盖不仅能够实现节约投入,而且可以增产增收,能够达到生态经济效益的最优。