小尾寒羊空怀母羊能量维持需要及其代谢规律研究   总被引：2，自引：0，他引：2  

杨在宾  李风双  杨维仁  张崇玉  林国茗  宋建兰 《动物营养学报》1996,(1)

选用体况良好,体重相近,经产2～3胎纯种小黾寒羊空怀母羊12只,随机分成3组,每组4只,分别按NRC(1978)推荐的绵羊维持代谢能需要量的120％、100％和80％饲喂。通过饲养试验、消化代谢试验及气体能量代谢试验测得小尾寒羊空怀母羊平均干物质采食量为756g,代谢能采食量力7869KJ,能量表观消化率为69.9％,代谢率为85.6％,甲烷能为总能量采食量(GEI,)的8.0％。空怀母羊在维持代态下呼吸商为0.872,畜体总产热为377.0KJ/kg W~(0.75)d。试验还证明,小尾寒羊空怀期母羊的维持净能需要为309.2KJ/kg W~(0.75)d,维持代谢能需要为408.8KJ/kg W~(0.75)d维持消化能需要为477.6KJ/kg W(0.75)d,维持效率(Km,)为0.756,热能耗为99.6KJ/kg W~(0.75)d,占GEI的14.36％。  相似文献   

Dietary copper requirements of juvenile grouper, Epinephelus malabaricus     

Yu-Hung Lin  Shi-Yen Shiau 《Aquaculture (Amsterdam, Netherlands)》2008,274(1):161-165

To quantify dietary copper (Cu) requirements in grouper, Epinephelus malabaricus, copper sulfate was added to the basal diet at 0, 1, 2, 4, 6, 8, 10 and 20 mg Cu/kg diet providing the actual dietary value of 0.11, 1.66, 2.41, 4.37, 6.56, 8.97, 11.03 and 20.05 mg Cu/kg diet, respectively. Each diet was fed to triplicate groups of grouper (initial body weight 13.35 ± 0.01 g) in a recirculated rearing system for 8 weeks. The Cu concentration in rearing water was monitored during the feeding period and ranged from 1.0-1.5 μg/l. Weight gain (WG) and feed efficiency (FE) were higher (P < 0.05) in fish fed diets with 4.37 and 6.56 mg Cu/kg diet than those in fish fed diets with ≥ 11.03 and ≤ 1.66 mg Cu/kg diet. Hepatic thiobarbituric acid reactive substances (TBARS) value was lowest in fish fed diets with 4.37 and 6.56 mg Cu/kg diet, intermediate in fish fed diets with 11.03 and ≤ 1.66 mg Cu/kg diet, and highest in fish fed the diet with 20.05 mg Cu/kg diet. Differences between each of the three groups were statistically significant (P < 0.05). Both hepatic copper-zinc superoxide dismutase (Cu-Zn SOD) and plasma ceruloplasmin activities in fish fell into four groups. Cu-Zn SOD value was highest in fish fed the diet with 6.56 mg Cu/kg diet, second highest in fish fed the diet with 8.97 mg Cu/kg diet, intermediate in fish fed the diet with 20.05 mg Cu/kg diet, and lowest in fish fed the diet with 0.11 mg Cu/kg diet; plasma ceruloplasmin was highest in fish fed the diet with 6.56 mg Cu/kg diet, second highest in fish fed diets with 2.41, 4.37 and 8.97 mg Cu/kg diet, intermediate in fish fed diets with ≥ 11.03 mg Cu/kg diet, and lowest in fish fed diets with ≤ 1.66 mg Cu/kg diet. All values in each of the four groups were significantly different from the values of three other groups (P < 0.05). Analysis by broken-line regression of WG, hepatic SOD activity and TBARS value and linear regression of whole-body Cu retention of the fish indicate that the adequate dietary Cu concentration in growing grouper is about 4-6 mg Cu/kg diet.  相似文献   

中国对虾对脂溶性维生素A,D_3,E,K_3的营养需要研究     

荣长宽  甄如林  岳丙宜  梁素秀 《天津农学院学报》1996,(2)

本试验应用正交设计L_9(4)~3,研究了中国对虾对配合饵料中脂溶性维生素A、D_3、E、K_3的营养需要。平均体重1.67～2.07g,体长5.20～5.70cm的幼虾,在本试验条件下,经20d饲养试验,结果经统计分析,以平均体重、体长生长比速为考察指标,结果中国对虾对100g配合饵料中脂溶性维生素A、D3、E、K3的营养需要量分别为;维生素A 4.00mg、维生素D_30.20mg、维生素E 45.00mg、维生素K_3 3.50mg。  相似文献   

Manganese requirement of sunflower (Helianthus annuus L.), tobacco (Nicotiana tabacum L.) and triticale (x Triticosecale W.) at early stage of growth     

Mrton Lszl 《European Journal of Agronomy》2008,28(4):586-596

Manganese deficiency symptoms are more often observed in crops at early stages of growth since Mn²⁺ can be easily mobilized from the surface soil. The objectives of this study were to evaluate some of the popular rotation crops grown in Hungary for tolerance to low external Mn²⁺ levels and to determine the critical tissue concentration for Mn²⁺ deficiency during early stages of growth. Indicator plants of sunflower (Helianthus annuus L.) were grown with NPKCaMg-fertilization induced of 0.0425–0.0700 g kg⁻¹; of tobacco (Nicotiana tabacum L.) 0.0237–0.0337 g kg⁻¹; of triticale (x Triticosecale W.) 0.0103–0.0327 g NH₄-acetate + EDTA extractable soil Mn²⁺ kg⁻¹; and were grown for 73, 50, and 191 days. The minimum Mn²⁺ concentration required in soil nutrient contents was 0.0425 g kg⁻¹ for sunflower, 0.0243 g kg⁻¹ for tobacco, and 0.0103 g kg⁻¹ for triticale. Sunflower, tobacco and triticale achieved optimum growth from 0.048 to 0.065 g Mn²⁺ kg⁻¹, from 0.0249 to 0.0321 g Mn²⁺ kg⁻¹, and from 0.0287 to 0.0296 g Mn²⁺ kg⁻¹, respectively. Critical ABP's dry weight Mn²⁺ concentration at early stages of growth was 0.0536 g kg⁻¹ in sunflower, 0.458 g kg⁻¹ in tobacco, and 0.1938 g kg⁻¹ in triticale. Our results demonstrate that the tolerance to low external Mn²⁺ (triticale <0.0302 g kg⁻¹; sunflower <0.0562 g kg⁻¹; tobacco <0.0693 g kg⁻¹) and the critical tissue Mn²⁺ levels for deficiency varied significantly among crop species tested.  相似文献   

大型仪器共享系统中冻干机的开放使用与维护     

梁艳英  魏冬梅  张莉 《安徽农业科学》2013,(7):3287-3288,3290

该文以西北农林科技大学葡萄酒学院的VIRTIS公司的GENESIS XL25冻干机的开放使用为例,介绍了冻干机的一般原理、结构和一般工艺流程,重点论述了大型仪器共享系统中冻干机开放使用的特点和对管理者的要求,提出了冻干机日常维护的注意事项。抛砖引玉来讨论大型仪器共享系统中仪器设备的管理和维护问题,以期更好地为教学科研服务。  相似文献   

中国玉米需水量与需水规律研究   总被引：27，自引：2，他引：27  

肖俊夫  刘战东  陈玉民 《玉米科学》2008,16(4):21-25

中国春玉米需水量变化在400～700mm,自东向西逐渐增加,低值区在东部牡丹江一带,高值区在新疆哈密一带。夏玉米需水量变化在350～400mm,济南附近为高值区;春玉米需水高峰期为7月中旬至8月上旬,即拔节-抽穗阶段,日耗水量达4.5～7.0mm/d。夏玉米需水高峰期为7月中下旬至8月上旬,同样在拔节-抽穗阶段,日耗水量达5.0～7.0mm/d。春玉米和夏玉米生长期棵间蒸发量分别占需水量的50%和40%。  相似文献   

泌乳母猪支链氨基酸的营养生理作用及需要量   总被引：1，自引：0，他引：1  

杨育才  董国忠 《中国畜牧兽医》1999,(2)

支链氨基酸（ＢＣＡＡ）是畜禽的必需氨基酸，对畜禽具有重要的营养生理作用。作者着重阐述支链氨基酸对泌乳的特殊作用，泌乳母猪对支链氨基酸的需要量，以及支链氨基酸及其代谢产物对蛋白质合成和降解的影响。  相似文献   

植物需水状况的精密诊断分析技术   总被引：2，自引：0，他引：2  

刘九庆 《森林工程》2004,20(5):22-24

针对目前我国水资源短缺的现状 ,提出基于植物水分诊断检测技术的闭环反馈控制系统来诊断植物水分亏缺状态。该系统的关键技术是研究设计精确测量叶片厚度的位移传感器  相似文献   

论数字图书馆对馆员的要求   总被引：3，自引：0，他引：3  

陈爱英 《农业图书情报学刊》2004,15(7):69-70,74

文章介绍了数字图书馆的特征，以及如何适应数字图书馆的要求，着重论述了数字图书馆馆员所具备的素质及相应的对策。  相似文献   

制种玉米需肥规律的研究   总被引：5，自引：0，他引：5       下载免费PDF全文

王勇索东让  孙宁科 《农学学报》2012,2(8):37-43

针对制种玉米开展需肥规律研究为平衡施肥技术的推广提供理论依据,同时提高制种产量,减少盲目施肥对生态环境的不良影响。在高、中、低3种施肥水平下进行多点田间试验,研究施肥量和产量的关系,使产量潜力得到最大发挥。测定主要生育时期干物质和养分累积进程,研究制种玉米需肥习性和需肥特点。结果表明,足量施肥条件下‘郑单958’和‘沈单16号’的平均种子产量为7744.5 kg/hm2;生产百公斤玉米种子需要N、P2O5、K2O等养分分别为2.653 kg、1.115 kg、3.449 kg;氮磷钾需肥结构为1:0.42:1.30;三叶期、六叶期、拔节期、抽雄期、灌浆期、成熟期干物质累积进程分别为0.11%、4.0%、21.3%、50.4%、94.9%和100%;苗期至拔节时段氮磷钾累积速率分别为43.6%、37.8%、58.3%,拔节至抽雄时段分别为22.1%、27.1%和18.3%,抽雄至灌浆时段分别为26.3%、19.9%和14.5%,灌浆至成熟时段分别为8.0%、15.7%和8.9%。中量施肥水平完全可以满足制种玉米养分需求,超量施肥对提高产量和养分吸收无明显影响,养分吸收峰值在拔节期。因此,在制种玉米施肥技术上要重施基肥,拔节期补施氮钾肥,抽雄期补施氮磷肥,即可满足制种玉米成熟期对养分的需求,同时也能获得较高的籽粒产量。  相似文献