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41.
矿区重金属污染十分严重,寻找并筛选适合当地生长的优势植物成为推广矿区植物修复技术的前提。铜绿山矿区土壤重金属铜含量高,在矿区发现4种优势植物。通过测定植物根际土壤及植物各器官铜含量,得出在此4种植物对铜的积累与迁移特点,评估其在矿区土地恢复与植被重建方面的作用与价值。  相似文献   
42.
日粮中添加铜对高产乳牛泌乳量影响的研究   总被引:3,自引:0,他引:3  
本研究探索了在奶牛日粮中添加Cu++对其产奶性能的影响.结果表明,在日粮中添加Cu++ 7.6×10-6,牛奶的乳脂率和干物质含量并未降低,牛奶中铜的残留量低于国家规定标准,能使奶牛泌乳量增产7.66%~9.61%,从而增加乳牛业的经济效益.  相似文献   
43.
44.
以泥鳅精子为受试材料,应用计算机辅助精子分析系统,研究硫酸铜(0.1、1、10 mg/L)对泥鳅的精子活力的影响.结果表明,在0 h试验组,0.1 mg/L的硫酸铜明显降低泥鳅精子运动速度,1 mg/L的硫酸铜对运动时间和速度产生显著抑制作用,10 mg/L的硫酸铜时运动百分数、运动时间和速度都产生明显影响(P<0.0...  相似文献   
45.
本研究旨在探讨高铜对雏鸡肾脏组织结构及生化指标的影响.360只1日龄艾维菌肉鸡随机分为6组,分别喂以对照日粮(Cu 10.89 mg·kg~(-1))和高铜日粮(Cu 100 mg·kg~(-1),高铜Ⅰ组;Cu 200 mg·kg~(-1)高铜Ⅱ组;Cu400 mg·kg~(-1),高铜Ⅲ组;Cu 600 mg·kg~(-1),高铜Ⅳ组,Cu 800 mg·kg~(-1),高铜Ⅴ组)6周.与对照组比较,高铜Ⅲ组、高铜Ⅳ组、高铜Ⅴ组雏鸡肾脏出现不同程度的病理损害,肾小管上皮细胞颗粒变性、空泡变性;超微结构观察,肾小管上皮细胞线粒体肿胀,嵴断裂,甚至溶解消失呈空泡状.同时,高铜Ⅲ组、高铜Ⅳ组、高铜Ⅴ组雏鸡肾脏及血清铜含量显著升高(P<0.01),肾脏铜锌超氧化物歧化酶(CuZn-SOD)活性显著降低(P<0.01),丙二醛(MDA)含量和羟自由基(·OH)含量显著升高(P<0.01).结果表明,日粮铜含量400 mg·kg~(-1)及其以上可引起雏鸡肾脏组织的病理损伤以及肾脏抗氧化功能的降低,导致肾脏功能降低.  相似文献   
46.
The distribution of copper and zinc among the soluble proteins in the liver and kidney from chronic copper-poisoned goats was examined after gel filtration of the proteins. The concentrations of copper in the liver and kidney cortex from five experimentally copper-poisoned goats were: 550–810 µg/g liver and 190–420 µg/g kidney cortex (wet weight). In general the copper-binding proteins from, both the liver and kidney samples were separated into two different fractions with approximate molecular weights (m.w.) of > 65,000 and 10,000, respectively. From the liver samples, varying amounts of copper were eluted in a fourth fraction with m.w. < 2,000. In the majority of kidney samples the dominating copper-binding protein fraction was the high molecular weight fraction. Absolute amounts of copper recovered in the metallothionein-like protein fraction were nearly the samt for all samples investigated. The distribution of zinc-binding proteins in both liver and kidney samples was nearly the same. The high molecular weight fraction dominated, and no zinc was bound to metallothionein-like proteins.  相似文献   
47.
铜中毒对雏鸭某些血液指标的影响   总被引:6,自引:4,他引:6  
选用1日龄天府肉鸭210只,随机分为3组,分别喂以对照日粮(Cu12.16mg/kg)、铜中毒日粮(Cu850mg/kg)和铜中毒日粮(Cu1050mg/kg)。试验期7周。以血液病理学方法观察了铜中毒对雏鸭某些血液学指标的影响。结果显示铜中毒组、组雏鸭分别于2周龄和3周龄开始出现临床症状,死亡18只和5只。血液病理学变化表现为,红细胞大小不等、变形变性、坏死溶解;红细胞数量和血红蛋白含量显著降低(P<0.01),血清谷丙转氨酶、谷草转氨酶活性显著升高(P<0.05或P<0.01),血清铜蓝蛋白活性下降。结果表明,铜中毒对雏鸭的生长发育和上述血液指标影响明显。  相似文献   
48.
The influence of different copper and zinc contents in rations on blood serum concentrations was tested in a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute for Animal Health (FLI). A total of 60 German Holstein breed cows (38 first lactating and 22 second lactating cows) were tested. All animals received a diet based on maize‐ and grass silage ad libitum. The animals were divided into two groups with 30 cows each. Group A received concentrates supplemented with copper and zinc as recommended, whereas Group B was offered a concentrate with roughly double the amount of copper and zinc. Blood samples were taken several times during the lactation. The concentrations of copper and zinc in the serum were measured and correlations between trace element intake and their serum concentrations were calculated. The mean dry matter intake was significantly higher for cows in the second lactation (19.1 kg/day) than for cows in the first lactation (16.4 kg/day), whereas the DM‐intake was constant in the different feeding groups (17.3 and 17.4 kg/day). The correlation between feed intake in the first and the second lactation was r = 0.76. The copper concentration in the serum was not influenced by the different feedings (11.9 and 12.5 μmol/l), but high variations were found between the cows. The influence of the lactation number was not significant (12.1 and 12.4 μmol/l). In contrast to copper, the zinc concentration in the serum was significantly higher for Group B (14.0 μmol/l) than for Group A (12.2 μmol/l), respectively, for second lactating cows (13.8 μmol/l) in relation to 12.7 μmol/l for first lactating cows. The individual variation was also high as for copper. Neither the correlation between copper intake and copper serum concentration nor the correlation between zinc intake and zinc serum concentration was significant.  相似文献   
49.
AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus).

METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 × 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial.

RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03–3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 µmol/L. In the deer grazing the control Mo pasture, this increased to 10.3 µmol/L on Day 112, before decreasing to 6.4 µmol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 µmol/L, respectively, on Day 112, and 2.5 and 3.3 µmol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 µmol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 µmol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Motreated pastures, liver Cu concentrations decreased to 55 and 52 µmol/kg fresh tissue, respectively, on Day 112, and 21 and 20 µmol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM.

CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to ≥4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.  相似文献   
50.
The pathological effects of copper deficiency (COD) are well known. However, the pathogenesis of cardiomyopathy resulting from COD remains unclear. In this study, aimed to elucidate the pathogenesis of COD-induced cardiomyopathy by examining the morphology of the cardiovascular system in copper-deficient rats using histopathology, immunohistochemistry, and scanning and transmission electron microscopy. Changes detected in the myocardium and interstitium were consistent with those reported for COD. Morphological changes included mesh-like changes in the capillary endothelial cells that appear to be a novel finding in COD-induced cardiomyopathy. These changes are hypothesized to result from abnormal vascular remodeling following damage to the basement membrane and due to the mechanical effects of myocardial contractions. Although cardiomyopathy may be associated with microcirculatory disorders arising from these lesions, further investigations are necessary to demonstrate a causal relationship between the pathogenesis of cardiomyopathy and the contribution of these lesions to disease progression.  相似文献   
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