纳米氧化铜对小白鼠铜表观消化率的影响

选40只20 g左右的健康昆明种小白鼠,随机分为4组.1组饲喂基础日粮;2组在基础日粮中以硫酸铜的形式添加铜10mg/kg;3组在基础日粮中以氧化铜的形式添加铜10mg/kg;4组在基础日粮中以纳米氧化铜的形式添加铜10mg/kg.采用全收粪法,研究纳米氧化铜对小白鼠铜表观消化率的影响.结果显示,硫酸铜组、氧化铜组、纳米氧化铜组小白鼠铜的表观消化率分别为54.74%、48.30%、71.88%,纳米氧化铜组铜的表观消化率显著高于硫酸铜组(P<0.05),极显著高于氧化铜组(P<0.01).试验表明,与添加硫酸铜和氧化铜相比,日粮中添加纳米氧化铜能提高小白鼠铜的表观消化率.     

纳米氧化铜对小白鼠血浆抗氧化机能的影响

选144只20g左右的健康昆明种小白鼠,随机分为6组,每组设4个重复。1组饲喂基础日粮;2组在基础日粮中以硫酸铜的形式添加铜10mg/kg;3组在基础日粮中以氧化铜的形式添加铜10mg/kg;4～6组在基础日粮中以纳米氧化铜的形式分别添加铜5、10、20mg/kg。研究不同剂量纳米氧化铜对小白鼠血浆抗氧化能力的影响,试验期30d。结果表明,添加纳米氧化铜显著提高小白鼠血浆铜蓝蛋白活力(P<0.05),显著提高小白鼠血浆细胞色素C氧化酶活性(P<0.05),显著降低30d小白鼠血浆丙二醛含量(P<0.05)。     

纳米氧化铜对小白鼠灌胃接种大肠杆菌致病性的影响

为了研究纳米氧化铜对小白鼠灌胃接种大肠杆菌致病性的影响,试验选择140只体重20g左右的昆明种小白鼠随机分为7组：1组为正常对照组,饲喂基础日粮;2组为感染对照组,饲喂基础日粮;3组为硫酸铜组,在基础日粮中以硫酸铜的形式添加铜180mg／kg;4,5,6,7组为纳米氧化铜组,分别在基础日粮中以纳米氧化铜的形式添加铜10,60,120,180mg／kg。结果表明：3组发病率明显低于2组;3组小白鼠肠道大肠杆菌数量显著少于2组（P〈0．05）,3,7组显著少于1组（P〈0．05）。说明日粮中添加高剂量纳米氧化铜能降低大肠杆菌致病性,但效果不如添加相同水平的硫酸铜。     

纳米氧化铜对小鼠全血及组织中铜和锌沉积的影响

选取240只体质量约22g健康的昆明种小白鼠,随机分为6组,每组设4个重复.1组饲喂基础日粮,2组在基础日粮中以硫酸铜的形式添加铜10mg/kg,3组在基础日粮中以氧化铜的形式添加铜10mg/kg,4～6组在基础日粮中以纳米氧化铜的形式分别添加铜5、10和20mg/kg.研究不同剂量纳米氧化铜对小白鼠全血和组织中铜及锌含量的影响.试验期30 d.结果表明,试验至15 d,添加纳米氧化铜显著提高小白鼠全血铜含量,显著降低小白鼠肝脏及胫骨锌含量;试验至30 d,添加纳米氧化铜显著提高小白鼠胫骨铜含量.     

纳米氧化铜时小白鼠灌胃接种大肠杆菌致病性的影响

为了研究纳米氧化铜对小白鼠灌胃接种大肠杆菌致病性的影响,试验选择140只体重20 g左右的昆明种小白鼠随机分为7组:1组为正常对照组,饲喂基础日粮;2组为感染对照组,饲喂基础日粮;3组为硫酸铜组,在基础日粮中以硫酸铜的形式添加铜180 mg/kg;4,5,6,7组为纳米氧化铜组,分别在基础日粮中以纳米氧化铜的形式添加铜10,60,120,180 mg/kg.结果表明:3组发病率明显低于2组;3组小白鼠肠道大肠杆菌数量显著少于2组(P＜0.05),3,7组显著少于1组(P＜0.05).说明日粮中添加高剂量纳米氧化铜能降低大肠杆菌致病性.但效果不如添加相同水平的硫酸铜.     

纳米氧化铜时对小白鼠灌胃接种大肠杆菌致病性的影响

为了研究纳米氧化铜对小白鼠灌胃接种大肠杆菌致病性的影响,试验选择140只体重20 g左右的昆明种小白鼠随机分为7组:1组为正常对照组,饲喂基础日粮;2组为感染对照组,饲喂基础日粮;3组为硫酸铜组,在基础日粮中以硫酸铜的形式添加铜180 mg/kg;4,5,6,7组为纳米氧化铜组,分别在基础日粮中以纳米氧化铜的形式添加铜10,60,120,180 mg/kg.结果表明:3组发病率明显低于2组;3组小白鼠肠道大肠杆菌数量显著少于2组(P<0.05),3,7组显著少于1组(P<0.05).说明日粮中添加高剂量纳米氧化铜能降低大肠杆菌致病性,但效果不如添加相同水平的硫酸铜.     

不同剂量纳米氧化铜对肉鸡免疫功能的影响

将180只1日龄健康AA肉仔鸡随机分为6组,每组设3个重复,第1、2、4、6组分别以硫酸铜、氧化铜、纳米氧化铜、纳米铜的形式在基础日粮中添加铜8mg/kg,3组和5组以纳米氧化铜形式在基础日粮中分别添加铜4mg/kg和16mg/kg,研究不同剂量纳米氧化铜对肉鸡免疫功能的影响.结果表明,与硫酸铜、氧化铜组相比,在饲料中以纳米氧化铜形式添加铜8mg/kg和16mg/kg,显著提高肉鸡免疫器官指数、新城疫抗体效价、淋巴细胞转化率和白细胞介素-2(IL-2)活性,以纳米氧化铜形式添加铜4mg/kg未引起机体免疫低下.由此可见,与硫酸铜相比,日粮中添加纳米氧化铜可提高肉鸡免疫功能.     

纳米氧化铜对雏鸡全血和肝脏铜含量及肝脏铜蓝蛋白mRNA表达的影响

选取1日龄SPF白莱航蛋用公雏63只,随机分为7组,1组受试鸡饲喂基础日粮;2～4组受试鸡分别饲喂以硫酸铜、氧化铜和纳米氧化铜的形式添加铜8mg/kg的饲料;5～7组受试鸡分别饲喂以硫酸铜、氧化铜和纳米氧化铜的形式添加铜175mg/kg的饲料。结果显示,日粮中添加铜8mg/kg或175mg/kg时,纳米氧化铜组受试鸡全血、肝脏铜含量显著高于氧化铜组、硫酸铜组和对照组(P<0.05);纳米氧化铜组受试鸡肝脏血浆铜蓝蛋白(CP)mRNA表达量显著高于硫酸铜组和氧化铜组(P<0.05)。试验至30d,日粮添加铜8mg/kg或175mg/kg时,纳米氧化铜组受试鸡血浆CP活性显著高于硫酸铜组和氧化铜组(P<0.05)。表明纳米氧化铜通过提高脏器组织铜沉积、上调铜酶或铜蛋白的基因表达来提高铜酶活性,从而发挥其生物学作用。     

不同剂量纳米氧化铜对肉仔鸡生长性能的影响

选180羽1日龄健康AA肉仔鸡，随机分为6组，每组设3个重复。第1、2、4和6组分别以硫酸铜、氧化铜、纳米氧化铜及纳米铜的形式在基础日粮中添加铜8mg／kg，3组和5组以纳米氧化铜形式在基础日粮中分别添加铜4和16mg／kg，试验期42d，研究不同剂量纳米氧化铜对肉鸡生长性能及器官指数的影响。结果表明，与硫酸铜和氧化铜组相比，在饲料中添加纳米氧化铜显著提高肉鸡平均日增质量（P〈0．05），显著降低料重比（P〈0．05），添加纳米铜显著提高1～14d平均日增质量；添加纳米氧化铜和纳米铜对肉鸡病死率无显著影响。     

纳米氧化铜对鸡肝细胞CP mRNA表达及培养基质中肝酶活性的影响

将培养48h的鸡原代肝细胞随机分为13组,每组3个重复。第1组为对照组,第2～5、6～9和10～13组分别以硫酸铜、氧化铜和纳米氧化铜的形式添加铜2、4、8、16mg/L,继续培养24h后检测上清中AKP、AST、ALT、γ-GT和LDH活性,用实时荧光定量PCR法检测肝细胞CP mRNA表达量。结果显示,以硫酸铜形式添加铜2～16mg/L、以氧化铜形式添加铜8～16mg/L和以纳米氧化铜形式添加铜16mg/L,培养基质中γ-GT活性均显著高于对照组（P〈0.05）;添加铜2mg/L时,硫酸铜组γ-GT活性显著高于纳米氧化铜组（P〈0.05）,添加铜8mg/L时,氧化铜组γ-GT活性显著高于纳米氧化铜组（P〈0.05）。添加铜2mg/L时,硫酸铜和氧化铜组AST和LDH活性显著高于对照组和纳米氧化铜组（P〈0.05）。添加铜2mg/L时,氧化铜组ALT活性显著高于纳米氧化铜组（P〈0.05）。添加铜8mg/L时,硫酸铜和氧化铜组AKP活性显著高于对照组和纳米氧化铜组（P〈0.05）。添加铜2～8mg/L时,肝细胞CP mRNA表达量显著高于对照组（P〈0.05）;添加铜2mg/L时,纳米氧化铜组肝细胞CP mR-NA表达量显著高于氧化铜组（P〈0.05）,氧化铜组显著高于硫酸铜组（P〈0.05）;肝细胞CP mRNA表达量随铜添加量的增加而降低。结果表明,基质中铜达到2mg/L时,纳米氧化铜比硫酸铜、氧化铜更有利于肝细胞生长,纳米氧化铜对体外培养肝细胞的损害作用低于硫酸铜和氧化铜。     

肉鸡对三碱基氯化铜、铜氨基酸螯合物、铜蛋白盐生物利用率研究

采用玉米—豆粕型饲粮研究肉公雏对三碱基氯化铜(TBCC)、铜氨基酸螯合物(CuAA)、铜蛋白盐(CuPro)或硫酸铜(CuSO4)的生物利用率。在基础饲粮(Cu14mg/kg,DM基础 ,实测值)上 ,TBCC、CuAA、CuPro、CuSO4 的铜添加水平依次为150mg/kg、300mg/kg、450mg/kg,试验3周。结果表明 ,铜源和铜水平对试鸡体重和饲料转化率的影响不显著。以CuSO4 为参比标准 ,铜添加水平或日粮铜摄入量为自变量 ,经对数转换后肝铜积累为因变量建立多元线性回归模型 ,按斜率法综合求测铜源生物利用率为 :CuSO4 100 % ;TBCC112.4 % ;CuAA127.7 %(P<0.01) ;CuPro99.3 %。结果表明TBCC或CuPro生物利用率与CuSO4同效 ,但CuAA生物利用率比CuSO4 高。该试验提供了评定肉鸡有机铜源生物利用率的实用方法。     

Copper status of ewes fed increasing amounts of copper from copper sulfate or copper proteinate

The Cu status of mature, crossbred ewes fed two sources (CuSO4 vs. Cu proteinate) and three levels (10, 20, or 30 mg/kg) of dietary Cu was determined in a 73-d feeding trial. Ewes (n = 30) were fed a basal diet containing rice meal feed, cottonseed hulls, cottonseed meal, meat and bone meal, cracked corn, and vitamin-mineral supplements at 2.5% of BW to meet NRC requirements for protein, energy, macrominerals, and microminerals, excluding Cu. The basal diet contained 5 mg/kg Cu, 113 mg/kg Fe, .1 mg/kg Mo, and .17% S. Copper sulfate or Cu proteinate was added to the basal diet to supply 10, 20, or 30 mg/kg of dietary copper in a 2x3 factorial arrangement of treatments. Ewes were housed in 3.7- x 9.1-m pens in an open-sided barn. Blood samples were collected on d 28 and 73. Ewes were slaughtered on d 74, and liver and other tissues were collected to determine Cu concentrations. An interaction (P = .08) occurred between source and level for liver Cu. The interaction existed due to an increase in liver Cu concentrations when ewes were fed increasing dietary Cu from CuSO4 but not when fed Cu proteinate diets. There was no source x level interaction (P>.10) for the blood constituents measured. On d 73, plasma ceruloplasmin activity was greater (P<.05) in ewes fed Cu proteinate than in those fed CuSO4 (33.1 vs. 26.8 microM x min(-1) x L(-1)). Increasing the concentration of dietary Cu did not affect (P>.10) plasma ceruloplasmin. Packed cell volume (PCV), red blood cell count (RBC), white blood cell count, whole blood hemoglobin (wHb), plasma hemoglobin, and plasma Cu were similar between sources of Cu. Ewes fed 20 mg/kg Cu had lower (P<.05) PCV, RBC, and wHb than those fed 10 or 30 mg/kg Cu diets. Feeding up to 30 mg/kg Cu from these sources did not cause an observable Cu toxicity during the 73-d period.     

Effects of source and level of copper on performance and liver copper stores in weanling pigs

Five 28- to 33-d experiments involving 460 crossbred pigs weaned at 28 +/- 2 d of age (initial weight, 6.7 to 8.1 kg) were conducted to determine the effects of feeding high dietary levels of Cu sulfate (CuSO4) or Cu oxide (CuO) on rate and efficiency of gain and liver Cu stores of weanling pigs. The pigs were housed in groups of five to six/pen and fed a fortified, unmedicated, corn-soybean meal-dried whey basal diet (1.1% lysine, 30 ppm Cu). In Exp. 1 and 2, pigs (eight replicates) were fed the basal or the basal plus 125 or 250 ppm Cu from CuSO4 or CuO for 28 d. In Exp. 3 and 4, four replications were fed the same diets as in Exp. 1 and 2 plus two additional diets (500 ppm Cu from CuSO4 or CuO). In Exp. 5, dietary levels of 0, 125, 250, 375 or 500 ppm Cu from CuSO4 were evaluated using four replications. At the end of each experiment, the liver from one pig in each pen was collected for Cu analysis. Overall, rate and efficiency of gain were improved (P less than .01) by feeding 125 or 250 ppm Cu as CuSO4, with the 125 ppm dietary level being about 75% as effective in stimulating growth as 250 ppm. Performance of pigs was not different from controls when the highest (500 ppm) level of Cu (from CuSO4) was fed. Liver Cu increased 10- to 70-fold when 250 to 550 ppm Cu from CuSO4 was included in the feed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of supplementing combinations of inorganic and complexed copper on performance and liver mineral status of beef heifers consuming antagonists.

Performance, immune response, and liver trace mineral status were measured in growing heifers supplemented with different copper (Cu) concentrations and sources when diets contained the Cu antagonists Mo, S, and Fe. Sixty Angus x Hereford heifers were managed in two groups for 112 d and were either individually fed diets and mineral treatments using individual feeding stalls (Stall) or pen-fed grass hay and individually supplemented mineral treatments (Pen). The basal diet of grass hay, rolled barley, and soybean meal was analyzed to contain 6 mg Cu/kg DM. The treatments consisted of 1) no supplemental Cu (Control); 2) 49 mg Cu/kg DM from Cu sulfate (i.e. approximately five times NRC recommendation for Cu from CuSO4) (5X-SO4); 3). 22 mg Cu/kg DM from CuSO4 (2X-SO4); 4). 22 mg Cu/kg DM from a combination of 50% CuSO4 and 50% Cu-amino acid complex (50-50); and 5). 22 mg Cu/kg DM from a combination of 25% CuSO4, 50% Cu-amino acid complex, and 25% Cu oxide (CuG) (25-50-25). All heifers were supplemented with the Cu antagonists Mo (10 mg/kg DM), S (2,900 mg/kg DM), and Fe (500 mg/kg DM). These diets resulted in dietary Cu:Mo ratios that averaged 0.5:1 for Control, 4.5:1 for the 5X-SO4, and 2.4:1 for 2X-SO4, 50-50, and 25-50-25. Rate and efficiencies of gain and cell-mediated immune function were not different (P > 0.10) among treatments. Data suggest supplements containing combinations of inorganic and complexed Cu interacted differently in the presence of Mo, S, and Fe. Heifers consuming the 25-50-25 supplement in the Stall group initially lost hepatic Cu rapidly but this loss slowed from d 50 to d 100 compared to the Control (P = 0.07), 50-50 (P < 0.05), and 2X-SO4 (P < 0.05) heifers and was similar (P > 0.10) to that in the 5X-SO4 heifers. In the Pen group, total hepatic Cu loss tended to be greater for 25-50-25 and 2X-SO4 compared to 5X-SO4 heifers (P = 0.09 and P = 0.06, respectively); Cu loss in the 50-50 heifers was similar (P > 0.10) to that in the 5X-SO4 heifers. This suggests that supplementing combinations of inorganic and amino acid-complexed Cu was as effective in limiting hepatic Cu loss during antagonism as was increasing dietary Cu levels to five times the NRC recommendation. A combination of 25% CuSO4 , 50% Cu-amino acid complex, and 25% CuO limited liver accumulation of Mo compared to supplements without CuO and could provide a strategic supplementation tool in limiting the systemic effects of Cu antagonism in beef cattle.     

Effects of dietary copper on the expression of lipogenic genes and metabolic hormones in steers

An experiment was conducted to determine the effects of Cu supplementation on performance, subcutaneous adipose tissue mRNA expression of acetyl CoA carboxylase (ACC), stearoyl CoA desaturase (SCD), uncoupling protein 2 (UCP2), and leptin in growing and finishing steers. Forty-eight purebred Angus steers were allotted to one of five treatments: 1) control (no supplemental Cu); 2) 10 mg Cu/kg DM from CuSO4; 3) 10 mg Cu/kg DM from a Cu amino acid complex (Availa Cu); 4) 20 mg Cu/kg DM from CuSO4; 5) 20 mg Cu/kg DM from Availa Cu. Steers were fed an alfalfa hay corn-based diet for 56 d (basal diet contained 7.1 mg Cu/kg DM) and switched to a high-concentrate diet for 144 d (basal diet contained 6.1 mg Cu/kg DM). Blood samples were obtained every 28 d throughout the entire experiment. On d 112 of the finishing period, subcutaneous adipose tissue biopsies were obtained from the tailhead of three animals per treatment and analyzed for ACC, SCD, UCP2, and leptin mRNA expression. Animal performance was not affected by Cu supplementation during the growing phase. Steers receiving 10 mg Cu/kg DM from Availa Cu had higher (P < 0.05) ending body weights and tended (P < 0.10) to have higher ADG than steers receiving 10 mg Cu/kg DM from CuSO4 during the finishing phase. Serum concentrations of nonesterified fatty acid and insulin were not affected by Cu supplementation. Steers receiving supplemental Cu tended (P < 0.11) to have less backfat relative to controls. However, dietary Cu did not influence the level of subcutaneous adipose tissue ACC and SCD mRNA. Neither UCP2 nor leptin gene expression was affected by Cu supplementation. These results indicate that dietary Cu supplementation (10 to 20 mg Cu/kg DM diet) may alter lipid metabolism of subcutaneous adipose tissue; however, it does not seem to affect expression of certain lipogenic genes.     

Growth response, blood characteristics and copper accumulation in organs of broilers fed on diets supplemented with organic and inorganic dietary copper sources

1. A 56-d experiment was conducted to study the comparative influence of organic and inorganic dietary copper (Cu) sources on growth, blood characteristics and copper accumulation in organs of broilers. 2. A total of 480 Arbor-Acre unsexed broilers were fed on diets containing copper sulphate (CuSO(4)) or copper proteinate (Cu Pro) at concentrations of 50, 100 or 150 mg/kg of Cu supplementation. The birds were given a broiler starter diet from 1-28 d and a broiler finisher diet from 29-56 d which contained 30·8 mg/kg and 41·1 mg/kg basal copper concentration respectively. Growth performance, blood characteristics and Cu accumulation in organs of the broilers were measured. 3. At 28 d, Cu Pro-fed birds had improved feed conversion ratio compared with CuSO(4). At 56 d, birds fed on Cu Pro diets had significantly greater body weight than CuSO(4)-fed birds. Birds fed on CuSO(4) supplemented diets had significantly better feed conversion efficiency. Feed consumptions for the two Cu sources were not significantly different. At no stage did the concentration of added Cu affect the productive traits measured. 4. Cu Pro supplementation increased haemoglobin concentration but reduced plasma triglyceride and plasma cholesterol. Plasma cholesterol decreased as Cu concentration increased. 5. There was a greater accumulation of Cu in the blood, heart, lung, liver and bone of broilers fed on Cu Pro than in those receiving CuSO(4). The liver Cu concentration increased as dietary Cu concentration increased. 6. Cu Pro was more effective in promoting growth and reducing blood cholesterol, and was more bio-available in the organs of broilers.