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171.
The concentrations of iron (Fe), copper (Cu), and zinc (Zn) were evaluated in 96 samples of the following eight fish species: Centropomus undecimalis, Caranx hippos, Scomberomorus brasiliensis, Lutjanus purpureus, Caranx crysos, Megalops atlanticus, Elops saurus, and Epinephelus itajara collected in the Atrato River Delta in the Gulf of Urabá. Three fish were caught from each of the following common fishing grounds: Bahía Candelaria, Bahía Marirrío, Bocas del Roto, and Bocas del Atrato. Fish were captured during a one-year period, with one specimen per species in each climatic period: dry, transient, and wet. The quantification was performed by microwave plasma-atomic emission spectroscopy. The highest levels of Fe and Cu were found in Caranx crysos, and highest level of Zn in Megalops atlanticus. According to the percentage of the daily value per food serving, Caranx crysos and Caranx hippos are good sources of Fe, and Caranx crysos is a good source of Cu.  相似文献   
172.
日粮中不同钼铜水平对肉牛血液生化指标的影响   总被引:4,自引:0,他引:4  
本研究旨在探讨日粮中不同钼铜水平对肉牛血液生化指标的影响。选用性别一致、年龄、体重相近(340±10)kg的3头健康未去势公牛作为试验动物。试验采用3×3拉丁方设计,分2期进行,第一期日粮钼的水平为0.27 mg/kg DM,第二期钼的水平为5.27 mg/kg DM。每期日粮铜的添加量分别为:10 mg/kg(低铜组),25 mg/kg(中铜组),50 mg/kg(高铜组)3个水平。颈静脉采血测定血铜、血清铜蓝蛋白(ceruloplasmin,Cp)和血浆中过氧化物歧化酶(superoxide dismutase,SOD)的活性。试验结果表明:在同一钼水平下,随铜水平的增加,牛体内血铜含量、血浆中SOD活性和血清Cp的活性逐渐增加。其中钼水平为0.27 mg/kg时,这种变化不显著(P>0.05)。钼水平为5.27 mg/kg时,添加10 mg/kg铜,血铜含量和血浆中SOD活性显著小于其他2个铜水平(P<0.05),Cp活性小于其他2个铜水平,且差异极显著(P<0.01)。在同一铜水平下,低钼组2种酶的活性普遍高于高钼组。日粮钼水平为0.27 mg/kg时,添加10 mg/kg铜可满足机体需要;日粮钼水平为5.27 mg/kg时,添加25 mg/kg铜较适宜:牛在缺铜时,与血浆SOD的活性比较,血清Cp更宜作为评价铜营养缺乏的指标;铜满足机体需要后,血铜、血清Cp和血浆SOD均对铜和钼的变化不敏感。血铜和血清铜蓝蛋白与日粮铜水平呈强相关。  相似文献   
173.
Bacterial leaf spot of lettuce, induced by Xanthomonas campestris pv. vitians, constitutes a major disease on commercial lettuce (Lactuca sativa) production in south Florida. Under greenhouse conditions, resorcinol, two antioxidants, and various sugar alcohols such as mannitol, were evaluated alone, and in combination with Tanos® 50DF (25% a.i. of each component cymoxanil and famoxadone, E.I du Pont de Nemours and Company, Wilmington, DE) for control of bacterial leaf spot. Among the compounds evaluated, resorcinol (35–50% disease control) and mannitol (9–45%) were the most effective. In field trials, different mixtures containing propionic acid, mannitol, resorcinol, Tanos and or copper hydroxide (Kocide 3000®, 46.1%, 30% copper equivalent) were evaluated for the control of bacterial leaf spot of lettuce. Field data support a moderate impact of Tanos in disease reduction. Both greenhouse and field data support a synergistic interaction between Tanos and the compounds including copper, in disease reduction. The mixture Tanos + resorcinol, or copper/resorcinol, Tanos + copper provided better or similar disease control than copper alone. No phytotoxicity was observed in our trials. In an integrated management program for bacterial leaf spot of lettuce, Tanos may be useful in tank mixes with these compounds and copper.  相似文献   
174.
175.
肉鸡实验性铜、锌中毒的研究   总被引:11,自引:2,他引:9  
20只30日龄的AA鸡,分为五组,每组4只,玉米-豆、菜饼型配合饲料作基础饲料。Ⅰ组加铜1600ppm,Ⅱ组加铜1600ppm、锌3000ppm,Ⅲ组加铜300ppm、锌5000ppm,Ⅳ组加锌5000ppm,Ⅴ组对照。结果表明,高铜在短期内引起严重中毒、生长抑制和死亡(4/4),主要表现为接触部位的腐蚀作用。吸收后主要是肝脏受损严重。肝、血和毛铜含量明显增加;高锌出现类似损害,但轻得多。肝、毛中锌含量明显增加;高铜低锌及低铜高锌的影响显示铜、锌的拮抗作用。  相似文献   
176.
姜璋  霍淑慧  袁莉 《安徽农业科学》2008,36(8):3077-3079
研究了3,6-双(4-溴-2磺基-苯偶氮)-4,5-二羟基-2,7-萘二磺酸(溴代磺酸偶氮Ⅲ)与铜的显色反应。结果表明,Cu(Ⅱ)与溴代磺酸偶氮Ⅲ形成了蓝色络合物,络合比为1∶1,该络合物最大吸收波长在616.8nm处,表观摩尔吸光系数ε=3.3×105L(/mol·cm),Cu(Ⅱ)在0-1.024μg/ml范围内符合比尔定律,检出限(3σ)为7.03×10-4μg/m(ln=20),相对标准偏差(RSD)是0.56%-4.68%。利用该法检测水果、蔬菜和茶叶中的铜,操作简便,灵敏度高。  相似文献   
177.
[目的]建立一种新的测定痕量铜的方法。[方法]在NH3-NH4Cl缓冲溶液(pH值9.76)中,阴离子表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)共同存在的条件下,Cu2+对H2O2氧化硫堇的褪色反应具有强烈的催化作用,据此建立了双表面活性剂增敏动力学光度法测定痕量铜的新方法。[结果]该方法的线性范围为0.004~0.480μg/ml,检出限为2.50×10-3μg/ml,催化反应的表观活化能为32.05 kJ/mol。[结论]该方法灵敏度高,操作简便、快速,可用于水样中痕量铜的测定。  相似文献   
178.
A survey was conducted in 10 districts of Northern India to record the copper deficiency in soil, fodder and serum samples. Significant deficiency of copper was observed in soil, fodder and serum samples of heifers. The copper deficient animals were listless, showed depigmentation of skin, stiff gait and were anaemic and diahorric. The purpose of the study was to evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes, vitamin and immune function which are affected by the deficiency of copper, so as to identify the parameters which can be of diagnostic importance in copper deficiency. Forty hypocuperemic heifers were selected from these areas and were randomly divided into two groups A and B. The heifers in group A were provided with mineral mixture containing copper sulphate and in group B without copper sulphate. Significant improvement (P<0.01) was observed in the haemoglobin (Hb), total leukocyte count (TLC) and total erythrocyte count (TEC) level at the 30th day of treatment in the animals of group A. Significant (P<0.01) improvement in serum. Ceruloplasmin (Cp) level was observed within 30 days of treatment, while significant (P<0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group A animals. Regarding hormones significant improvement was observed in T(3) and T(4), in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (P<0.01) improvement within 30th days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (P<0.01) improved in group A within 60 days of treatment. Similarly significant improvement in superoxide dismutase activity in RBC was observed at the 30th day, and WBC and whole blood at 60th day in group A animals. Significant improvement in liver Cu level was observed at the 30th day of treatment, while in group B the liver Cu was significantly (P<0.01) depleted at the 60th day of experimentation. Additional Cu supplementation improved growth performance significantly in group A.  相似文献   
179.
180.
介绍了铜素的生理功能及烟株对铜素营养的吸收分配规律,概述了铜素对烟草生理生化的调控及对烟草产量和品质的影响,提出了进一步加强对烟草铜素营养研究的建议。  相似文献   
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