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251.
[目的]研究日粮中添加番茄渣发酵饲料对新疆褐牛生产性能、乳成分、血细胞参数及经济效益的影响.[方法]选泌乳日龄(86 ±29)d,体重(467±28) kg的2~3胎、健康、泌乳量相近的新疆褐牛20头分为2组,饲喂常规日粮(对照)和用14;番茄渣发酵饲料(CP≥26;,DM;主成分番茄渣,添加碳氮源后接种有益微生物)替代对照组日粮6;棉粕、4.5;麸皮和3.5;玉米青贮(DM).[结果]与对照组相比,新疆褐牛添喂番茄渣发酵饲料显著提高DM采食量、4;校正乳产量(P<0.05),分别提高5.12;、5.83;.番茄渣发酵饲料组的乳产量、饲料转化率、乳脂率、乳蛋白、乳糖、总固体固形物在数值上高于对照组,但差异不显著(P>0.05),分别提高4.07;、0.62;、2.65;、2.83;、1.62;和1.48;;番茄渣发酵饲料组乳中体细胞数低于对照组(P=0.15).添喂番茄渣发酵饲料有提高外周血红细胞数的趋势(P=0.07).添喂番茄渣发酵饲料比对照组每日每头增收效益1.79元,增幅9.68;;每头牛每月(按30 d计)可多收入53.7元.[结论]添喂14;的番茄渣发酵饲料可提高新疆褐牛的DM采食量、4;校正乳产量及经济效益.  相似文献   
252.
Direct-seeded rice culture in Sri Lanka: Lessons from farmers   总被引:1,自引:0,他引:1  
About 95% of the rice grown in Sri Lanka is direct-seeded (wet- and dry-seeding). The average rough rice yield in irrigated predominantly direct-seeded dry zone (DZ) is about 5.0 t ha−1and in the wet zone (WZ) it is about 3.3 t ha−1. However the average realizable yield in DZ and WZ are 8 t ha−1 and 5 t ha−1 respectively. A survey was conducted to understand the cultural practices, farmers’ perceptions and the reasons for the yield gap in direct-seeded rice culture in Sri Lanka. Farmers’ seed rate ranged from 87 to 220 kg ha−1 for intermediate bold-type varieties and from 71 to 176 kg ha−1 for varieties with short round grains. About 90% of the farmers in the DZ and the intermediate zone (IZ) consider both yield potential and duration as criteria in selecting a variety. Among the farmers surveyed, only 21% of the farmers in the DZ, 13% of the farmers in the IZ, and 29% of the farmers in the WZ adhered to the recommended method of basal fertilizer application. Farmers did not adhere to the correct timing of fertilizer application. More than 50% of the cost for rice farming goes to labor, followed by cost of inputs in all climatic zones. Farmers reported that the most important production constraint for direct-seeded rice in the DZ and IZ is the non availability of reliable labor followed by soil problems and weeds. While in the WZ, it is the soil problems specially iron toxicity followed by lower soil fertility. The survey revealed that smaller land holding size, non adherence to the optimum time of farm activity initiation, less efficient use of rain water, higher seed rate and higher cost of production are a few reasons for the existing yield gap. Location-specific technologies for different agro-ecological zones of Sri Lanka should be developed to reduce the cost of production and to increase resource-use efficiency and should be transferred to the farmers to achieve sustainable optimum direct-seeded rice yields.  相似文献   
253.
由白背飞虱Sogatella furcifera(Horváth)传播的南方水稻黑条矮缩病毒(Southern rice blackstreaked dwarf virus,SRBSDV)是目前我国南方水稻上危害最严重的病毒,为开发简便、快速、准确的SRBSDV病毒检测技术和检测试剂,以感染SRBSDV的植物粗提液为免疫原,利用杂交瘤技术制备了2株抗SRBSDV的单抗(14A8和15G6),并利用制备的单抗建立了可快速、特异、灵敏地检测SRBSDV的胶体金免疫试纸条。结果表明,2株制备单抗的抗体类型及亚类均为Ig G1、kappa链,单抗腹水的间接ELISA效价均达到10~(-7);Western blot分析表明,2株单抗均与SRBSDV的外壳蛋白亚基有特异反应,而不与水稻黑条矮缩病毒(Rice black-streaked dwarf virus,RBSDV)反应。以制备14A8和15G6单抗分别为捕获抗体和胶体金标记抗体,开发成能在5 min内准确、特异地检测水稻植物和白背飞虱传毒介体体内SRBSDV的胶体金免疫试纸条;灵敏度分析表明,该检测试纸条的检测水稻病叶的灵敏度达到1∶6 400倍(g/m L),检测单头携毒白背飞虱的灵敏度达到1∶51 200倍(单头/μL)。田间样品检测结果表明,该试纸条的检测结果与RT-PCR的符合率达到100%。建立的SRBSDV胶体金免疫试纸条可对南方水稻黑条矮缩病毒进行快速、特异、灵敏的诊断和检测。  相似文献   
254.
Expression of Kit ligand (KL) and insulin‐like growth factor binding protein (IGFBP3) genes was studied at different in vivo and corresponding in vitro stages of development of the ovarian follicles in sheep. The expression of both KL and IGFBP3 was significantly higher in the primordial follicles relative to any other stage of development. Compared to the other stages, the KL expression in the cumulus cells from in vivo grown large antral follicles and that of IGFBP3 in COCs’ isolated from large antral follicles matured in vitro for 24 hr were significantly higher. In the oocytes from in vivo grown ovarian follicles, the expression of KL was the same at all the stages of development. Insulin‐like growth factor binding protein 3 expression was also the same in the oocytes at all the stages of the development except for a significantly lower expression in those from antral follicles. The expression of KL in the cumulus cells decreased significantly in the in vitro grown early antral follicles but did not change further as the development progressed. The expression of IGFBP3 in the cumulus cells from in vitro grown ovarian follicles appeared to increase as the development progressed although the increase was not significant between any two consecutive stages of development. In the oocytes in in vitro grown ovarian follicles, the expression levels of KL and IGFBP3 genes did not change with development. It is concluded that (i) KL and IGFBP3 genes follow specific patterns of expression during ovarian folliculogenesis and (ii) in vitro culture of preantral follicles compromises the development potential through alterations in the stage‐specific patterns of expression of these and other developmentally important genes.  相似文献   
255.
对闽北山地坡位对湿地松生长和养分利用效率的影响进行了研究,结果表明:坡位对湿地松幼林的生长有显著影响,中坡和下坡湿地松的树高、胸径和单株材积显著大于上坡;不同坡位上湿地松幼林的林分生物量为下坡(9 522kg hm~(-2))中坡(7 137kg hm~(-2))上坡(6 266kg hm~(-2));不同坡位上湿地松对养分的利用效率不同,其中中坡对氮、磷的利用效率显著高于上坡和下坡,下坡对钾、钙、镁、铁的利用效率高于上坡和中坡。  相似文献   
256.
This study aims to evaluate the conjunctiva colour-based FAMACHA score (FS) coupled with a body condition score (BCS), haemogram and stressor hormone level estimation, in identifying post-mortem (PM)/coproscopically proven individuals wanting therapy for economically important gastrointestinal (GI) helminths, Haemonchus contortus, in the small ruminants. The incidence of haemonchosis was significantly (p < 0.05) higher (60.81%) in the ruminants with FS = 3. The H. contortus count in the animals with FS 2, 3 and 4 was 23.2 ± 0.37, 62 ± 2.5 and 74 ± 3.2 (p < 0.05) [positive correlation (r = 0.841 in goats; r = 0.828 in sheep, p < 0.05)], respectively, with corresponding 2.8 ± 0.15, 2 ± 0.3 and 2 ± 0.16 BCS (negative correlation, p > 0.05). The infected animals of FS 2, 3 and 4 measured 8.2 ± 0.0, 7.5 ± 0.23 and 6.7 ± 0.34 g/dl Hb (r = ?0.452, p = 0.01) in goats/9.3 ± 0.8, 8.6 ± 0.5 and 7.6 ± 0.3 g/dl Hb (r = ?0.511, p = 0.05) in sheep with 21.2, 19.8 ± 1.8 and 17.8 ± 0.2% PCV (r = ?0.369, p = 0.05) in goats/26.7 ± 1.2, 22.2 ± 0.2 and 20.9 ± 0.6% PCV (r = ?0.251, p = 0.03) in sheep, respectively. The FS 2, 3 and 4 infected goats/sheep measured 6.1 ± 0, 7.9 ± 1.0 and 9.5 ± 0.9 (p < 0.05)/5.8 ± 2.3, 6.9 ± 1.2 and 7.8 ± 0.2% (p < 0.05) mid-granulocyte [(r = 0.928 (goats)/0.834 (sheep), p < 0.05], while the cortisol level was 15.6, 23 ± 4.5 and 42 ± 2.3 (p = 0.23)/12.1 ± 0, 15.9 ± 1.2 and 24 ± 3.4 (p = 0.29) μg/dl, respectively. The infected ruminants recorded low (p < 0.05) level of Hb/PCV while high level of mid-granulocytes/cortisol. Specificity of FAMACHA test was maximized (100%) when FS = 4 was considered anaemic, but sensitivity was low (35.29% in goats; 25% in sheep). The false negatives was 5.9 (goat)/12.5 (sheep)% when FS ≥ 3 was considered anaemic. The small ruminants with FS ≥ 3, BCS ≤ 2.5, Hb ≤ 7.5 g/dl (goats)/8.6 g/dl (sheep), PCV ≤ 19.8% (goats)/22.2% (sheep) and mid-granulocyte ≥7.9% (goats)/6.9 ± 1.2% (sheep) can be subjected to target-selective treatment for haemonchosis in the field simultaneously maximizing the economic benefit to the farmers.  相似文献   
257.
不同基因型香蕉对钾高效吸收的根系形态学和生理学特征   总被引:1,自引:0,他引:1  
利用Hoagland营养液培养,设计0.25 mmol/L(低钾)、2.5 mmol/L(高钾)2种水平,初步探讨4个不同基因型香蕉对低钾适应性。结果表明:钾高效品种在根系活跃吸收面积,总吸收面积,比表面积、及根系活力大于钾低效品种。钾高效香蕉品种根系吸收钾的Km值、Cmin都小于钾低效品种,而Imax和a值普遍大于钾低效品种,钾高效品种在低钾胁迫下通过提高丙二醛、可溶性蛋白含量和SOD酶活性实现钾素利用的保护性反应,具有较强的自我保护能力。  相似文献   
258.
景宁县白茶品系性状品质比较研究   总被引:1,自引:1,他引:0  
柳蓓  叶丽敏  朱焕明  刘饶  王建林  刘慧平 《茶叶》2010,36(3):156-158
白茶是我国特有的茶树品种资源。通过对景宁白茶6个品系性状特征观测比较,春茶生化品质检测和加工产品感官评审,为该县茶叶品质提升和白茶开发利用提供基础资料。  相似文献   
259.
白玉仙茶扦插育苗技术研究   总被引:4,自引:1,他引:3  
刘饶  朱焕明  刘慧平  吴锡金  毛昌会  叶有奇 《茶叶》2010,36(1):19-20,18
通过对时间、扦插基质、植物生长调节剂和插穗部位4个因素对白玉仙茶两个品系进行扦插繁殖研究。结果表明白玉仙茶Ⅱ扦插成活率比白玉仙茶Ⅰ高15%,且生长势明显;夏季嫩枝扦插,分别比白玉仙茶Ⅰ冬季和春季扦插成活率提高13%和23%,但对白玉仙茶Ⅱ作用不明显;扦插基质为1/2普通苗床土+1/2黄沙的成活率比全部用黄心土的约高5%;合适浓度的植物生长调节剂IBA对扦插成活促进明显,但高浓度反而有抑制作用;插穗部位几乎不影响扦插成活率。  相似文献   
260.
猪复合预混料中微量元素含量的调查分析初探   总被引:1,自引:0,他引:1  
通过对9家预混料生产厂家的4%系列猪用预混料的调查研究,以期了解预混料微量元素的含量。调查结果表明,在抽查的9家预混料生产厂家中,共45个产品中铜、铁、锰、锌的自定标准值和实测值都极大超过了中国肉脂型生长肥育猪和妊娠母猪的饲养标准(1986)和美国NRC(1998)建议的猪营养需要量。铅、砷等危害极大的元素须严格的控制。铜、铁、锰、锌等微量元素的大量添加,虽然可以提高猪的生产性能,但会对环境造成极大的危害。  相似文献   
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