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61.
3种豆科牧草山地红壤适应性评价 总被引:1,自引:0,他引:1
在山地红壤中对印尼大绿豆、印度豇豆和白扁豆等3种豆科牧草进行适应性种植评价试验,结果表明印尼大绿豆具有生育期长(201d),鲜草产量高(59774.4kg/hm^2),粗蛋白含量高(16.92%),生长表现良好,饲用价值高特点,便于推广利用。 相似文献
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L.G. Lapchic A.J. Clark G.P. Lomonossoff M. Shanks 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(4):409-412
The relationship between red clover mottle virus (RCMV) isolated in the Ukraine (designated RCMV-Uk) and well-characterised strains from Sweden has been investigated. Nucleic acid hybridisation indicate that both RNAs from RCMV-Uk are highly homologous to their counterparts from RCMV strain S, a conclusion supported by protein sequence analysis of the two viral capsid proteins. Nucleic acid sequence analysis of a portion of RCMV-Uk RNA2 confirmed the high degree of similarity between RCMV-Uk and RCMV strain S. This information suggests that RCMV-Uk should be considered an isolate of RCMV strain S. 相似文献
65.
The antioxidant status of the red blood cells of buffaloes (n = 20) suffering from post-parturient haemoglobinuria (PPH) was assessed by comparing their tocopherol (vitamin E) and reduced glutathione contents with those of red blood cells from apparently healthy buffaloes (n = 20). The red cell tocopherol content of the diseased buffaloes (1.76±0.11 g/ml) was significantly (p<0.01) lower than that of healthy buffaloes (2.45±0.14 g/ml). This may be the first report comparing the concentration of tocopherol in the red blood cells of buffaloes suffering from PPH and apparently healthy buffaloes.There was a drastic reduction in the reduced glutathione content in the red cells of haemoglobinuric buffaloes (23.74±2.86 mg%) compared to the healthy control buffaloes (73.71±3.87 mg%). The diseased buffaloes also exhibited severe hypophosphataemia. These findings suggest that an impaired or insufficient antioxidant potential of the red blood cells in this disease in buffaloes is associated with the phosphorus deficiency. 相似文献
66.
氯霉素在草鱼和复合四倍体异育银鲫体内的比较药代动力学 总被引:9,自引:0,他引:9
研究并比较了给草鱼和复合四倍体异育银鲫(简称高倍体鲫鱼)单次腹腔注射氯霉素100mg/kg后的药代动力学特征。采用HPLC测定血液中氯霉素的浓度。试验期间水温为(20±2)℃。结果表明,氯霉素在这2种鱼体内的处置过程相似,均可用带一级吸收的二室开放模型进行描述;药物从腹腔吸收迅速,给药后分别在0.92h和0.63h血中浓度达到高峰,无吸收时滞;在草鱼和高倍体鲫鱼体内药物的t12β相近,分别为11.9h和11.1h,但体清除率(ClB)相差较大;氯霉素在高倍体鲫鱼体内比在草鱼体内有更强的亲组织性,总表观分布容积(Vd)分别为2.07和1.20L/kg。 相似文献
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Effects of different dietary protein and lipid levels on growth, feed utilization and body composition of red porgy (Pagrus pagrus) fingerlings 总被引:1,自引:0,他引:1
D. SCHUCHARDT J.M. VERGARA H. FERNÁNDEZ-PALACIOS C.T. KALINOWSKI C.M. HERNÁNDEZ-CRUZ M.S. IZQUIERDO & L. ROBAINA 《Aquaculture Nutrition》2008,14(1):1-9
Two feeding trials were conducted to determine the minimum dietary protein level producing maximum growth, and the optimum protein to energy ratio in diets for red porgy (Pagrus pagrus) fingerlings, respectively. In the first trial, six isoenergetic diets were formulated with protein levels ranging from 400 to 650 g kg?1 in increments of 50 g kg?1, and fed for 11 weeks to 2.8 g average initial weight fish. Weight gain, specific growth rate and feed efficiency were significantly higher with diets containing higher protein levels, when compared with dietary levels below 500 g kg?1. The highest protein efficiency ratios were obtained in fish fed 500 g kg?1 dietary protein. The minimum dietary protein level producing maximum fish growth was found to be 500 g kg?1. In the second trial, 15 g average initial weight fish were fed for 12 weeks, six diets containing three different lipid levels (100, 150 and 200 g kg?1) combined with two protein levels (450 and 500 g kg?1). Weight gain values increased when dietary lipids increased from 100 to 150 g kg?1, with a further decrease for 200 g kg?1 lipids in diets; the lowest fish growth being supported by 200 g kg?1 dietary lipids. Fish growth was significantly higher when dietary protein increased from 450 to 500 g kg?1. There was no evidence of a protein‐sparing effect of dietary lipids. Liver protein and lipid contents were low when compared with other fish species. All diet assayed produced high liver glycogen accumulation. The recommended protein and lipid levels in diets for red porgy fingerlings were 500 and 150 g kg?1, respectively. 相似文献
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从养殖锦鲤各种组织中提取完整的RNA, 是分子生物学研究锦鲤应激表达、体色变异、生长发育等功能基因表达的关键实验。在不伤害养殖锦鲤个体健康的情况下, 取用鱼体的鳍条、鳞片、鳃丝、血液4种保护性组织,可以最大程度地减少对珍贵锦鲤个体的损伤, 并达到研究相关基因表达的目的。本研究利用TR izo l法提取RNA, 获得的各样品RNA条带完整、纯度高。结果表明, 4 种保护性组织提取的RNA 经过逆转录反应, 得到了高质量的CDNA。内标基因( B- actin)、热激蛋白基因( hsp70)、金属硫蛋白基因(MT)扩增得到清晰的条带, 通过NCB I数据上的BLAST比对证明, 各序列的同源性在95%以上。利用本研究的方法, 可以充分保护养殖锦鲤个体的完好性, 用于进一步的分子生物学研究。 相似文献
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以长期定位试验为基本材料,研究了湘南3种典型红壤生土25年长期施肥对作物产量的影响。结果表明:(1)25年作物累计产量以紫色土为最高,其次是花岗岩红壤,第四纪红壤最低。(2)3种母质生土熟化过程中,对于不同处理,平衡施用氮磷钾化肥处理,均能获得较高作物产量,显著高于施用有机物料稻草处理,显著高于对照处理。施肥是加速红壤母质熟化的主要途径和方法。(3)对于不同处理方式,作物归还条件下其作物产量要高于不归还。(4)供试的3种土壤在熟化的过程中对植被的影响非常明显,在熟化的初期,许多作物在花岗岩发育的和第四纪红土发育的土壤上,都生长不好,然而在施有NPK的处理中,马唐草(Dischaemum Schreb)生长特别茂盛(覆盖度100%,高lm),明显地影响了土壤的水热状况,紫色土上马唐草生长不好。(5)种植小麦和黄豆,花岗岩、四纪红土NPK处理靠小区水泥梗边缘要好,小区中间95%部分长势差,叶片淡黄,植株矮小。(6)花岗岩红壤和第四纪红壤二种母质熟化24年后(即2005年)种植豆科作物—黄豆和禾本科作物小麦(2006年),其作物产量均表现为:0M>NPK。 相似文献
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