The Concentrations of Molybdenum and Zinc in Liver in Relation to Copper Accumulation in Normal and Copper Poisoned Sheep

The concentrations of copper, molybdenum and zinc were measured in the liver of normal grazing sheep and lambs from Eastern Norway, and in sheep dead of chronic copper poisoning. The following mean values were found: Normal sheep: 173 ± 130 μg Gu/g wet weight, 1.0 ±0.3 μg Mo/g, and 49 ± 10 μg Zn/g; lambs: 129 ± 59 μg Gu/g, 0.9 ± 0.3 μg Mo/g, and 46 ±9 μg Zn/g; sheep dead of copper poisoning: 429 ± 249 μg Gu/g, 0.4 ± 0.1 μg Mo/g, and 43 ± 2d μg Zn/g. Sheep with low liver copper (Gu < 10 μg/g) were also analyzed for molybdenum and zinc, with the following results: 1.0 ± 0.2 μg Mo/g, and 45 ± 8 μg Zn/g wet weight. The differences in liver copper between all the groups, and the differences in molybdenum concentrations between the normal sheep and the lambs and between the normal sheep and the poisoned sheep were significant (P < 0.001). No significant correlations between liver copper/liver molybdenum or liver copper/liver zinc were detected.     

外源硒对绵羊孕期体内硒、铜、锌的影响

比较研究在相同的饲养管理条件下,孕期补硒对不同品种绵羊血清中硒（Se）、铜（Cu）、锌（Zn）含量的影响。以处于怀孕期的85只蒙古羊、道赛特羊和萨福克羊为研究对象,通过荧光分光光度法测定Se含量、原子吸收法测定Cu、Zn含量。结果显示,补Se各品种羊从怀孕3个月起血清Se含量显著高于未补硒同品种羊（P＜0.05）,补Se与未补Se同品种羊血清Zn含量在各期差异不显著（P＞0.05）,补Se与未补Se蒙古羊血清Cu含量各期差异不显著（P＞0.05）。结果表明,Se与Cu、Zn不具有颉颃作用,说明补Se对母体维持正常妊娠和增强抗病性功能具有重要作用。     

外源硒对绵羊孕期体内硒、铜、锌及相关抗氧化酶的影响

为了研究在相同的饲养管理条件下孕期补硒对不同品种绵羊血清中硒、铜、锌含量及铜锌超氧化物歧化酶（CuZn—SOD）、超氧化物歧化酶（T—SOD）活性的影响。以处于怀孕期的85只蒙古羊、道赛特羊和萨福克羊为研究对象,测定硒、铜、锌含量和CuZn—SOD、T—SOD活性。结果表明：补硒羊从怀孕3个月起血清硒含量显著高于未补硒同品种羊（P〈0．05）,补硒与未补硒同品种羊血清锌含量在各期差异不显著（P〉0．05）;补硒与未补硒蒙古羊血清铜含量各期差畀不显著（P〉0．05）;补硒后各品种羊怀孕3个月时CuZn—SOD、T—SOD活性显著高于未补硒同品种羊（P〈0．05）。结果说明硒与铜、锌不具有颉颃作用,补硒能够显著提高血清CuZn—SOD、T—SOD活性,说明补硒对母体维持正常妊娠和增强抗病功能具有重要作用。     

Histochemigal Detection of Copper in the Liver from Sheep Chronically Poisoned by Copper

Continued ingestion of copper in excess of the nutritional requirement leads in all animals to its passive accumulation within the tissues, especially the liver. Up to certain levels varying greatly with the species high concentrations of copper in the liver appear to impose no physiological hardship on the animal. Above these levels there may occur a catastrophic liberation of a high proportion of the copper into the blood stream resulting in extensive hemolysis and jaundice usually followed by death. Sheep are more prone to the hemolytic crisis of chronic copper poisoning than other animal species. The hemolytic crisis of chronic copper poisoning is associated with centrolobular necrosis of the liver. The copper concentration in the liver is usually 300 p.p.m. or more (wet tissue) compared with about 50 p.p.m. in normal sheep (Simesen & Møller 1969).     

不同铜源和水平对肥育绵羊生产性能、铜状态和抗氧化能力的影响

为研究不同铜源和水平对肥育绵羊生产性能、铜状态和抗氧化能力的影响,本试验选用50只体重相近(23.8±1.6)kg、3月龄左右的杜泊×蒙古羊杂交一代羯羊,随机均分为5组,对照组饲喂基础日粮(不加铜)、试验组分别在基础日粮中添加10、20mgCu/kgDM赖氨酸铜和10、20mgCu/kgDM碱式氯化铜。结果表明:2种铜源和水平对肥育绵羊生产性能无显著影响(P>0.05)。补加铜显著增加了绵羊血浆铜浓度(P<0.05),极显著增加肝脏铜浓度和血浆Cp活性(P<0.01)。补加铜显著降低了血浆和肝脏中MDA浓度(P<0.05),提高了血浆SOD活性(P<0.05)。赖氨酸铜和碱式氯化铜对绵羊铜状态和抗氧化能力的影响相同,10、20mgCu/kgDM2种铜水平对绵羊抗氧化能力的影响也相同,但随着铜添加水平的增加绵羊体内铜状态提高。     

Fluorometric Selenium Determinations in the Liver of Normal Pigs and in Pigs Affected with Nutritional Muscular Dystrophy and Liver Dystrophy

The selenium concentration of livers and kidneys in normal pigs and in pigs affected with nutritional muscular dystrophy (NMD) and liver dystrophy (LD) was determined. The kidney values showed great variation in normal pigs. The young pigs generally had the lowest levels. The liver values were less scattered.In NMD and LD the liver contained about 0.2 ppm of selenium on the average, whereas normal livers contained about 1.2 ppm. Kidneys showed corresponding differences. This is in good agreement with the favourable results obtained with selenium therapy.     

纳米硒对肉鸡肝脏硒含量和抗氧化能力的影响

试验选用1日龄艾维茵(Avian)肉鸡225只,随机分为5个处理组,每组设3个重复,研究纳米硒对肉鸡肝脏硒含量和抗氧化能力的影响。在玉米-豆粕型日粮基础上添加纳米硒0、0.15、0.3、0.6、1.2mg/kg,基础日粮组为对照组,试验期6周。结果表明:42日龄时,日粮中添加纳米硒显著提高了肝脏总抗氧化能力、谷胱甘肽过氧化物酶活力、总超氧化物歧化酶活力、抑制羟自由基能力(P<0.05),显著降低了肝脏丙二醛含量、一氧化氮含量(P<0.05),极显著提高了肝脏硒含量(P<0.01)。而且随日粮中纳米硒添加量的增加,肝脏抗氧化能力和硒含量均呈二次曲线关系。因此,肉鸡日粮中纳米硒的适宜添加水平为0.7～1.0mg/kg。     

外源硒对绵羊围术期血清Cu、Zn及相关抗氧化酶的影响

为探讨术前补充适量的硒对绵羊瘤胃瘘管术中及术后氧化-抗氧化系统的影响及其可能机制,将试验动物分为添硒组、对照组,并按计划采颈静脉血,测定其血清微量元素Cu、Zn、Se的含量以及相关的T-SOD、CuZn-SOD及GSH-Px的变化规律.结果表明,术后两组试验羊血清T-SOD、CuZn-SOD与GSH-Px的变化显著,并且补硒组相对于对照组应激程度趋于缓和,且较早地恢复到术前水平.围术期内补硒组Se含量、T-SOD、CuZn-SOD及GSH-Px活性均高于对照组.两组试验羊血清Zn变化趋势呈现下降趋势, 血清Cu含量变化趋势不明显.试验证明术前补充适量的硒能够有效地提高机体的抗氧化能力,促进手术创伤早期恢复,从而为评价瘤胃瘘管术后动物的预后提供一定依据.     

The Distribution of Soluble Copper- and Zinc-Binding Proteins in Liver and Kidney of Chronic Copper-Poisoned Goats

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.     

不同硒浓度日粮对小鼠肝脏和睾丸组织中部分硒蛋白mRNA水平的影响

选取80只7周龄雄性BALB/c小鼠,随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ组,每组20只,使Ⅰ、Ⅱ、Ⅲ、Ⅳ组基础日粮中硒含量达到0.045、0.1、0.4和0.8 mg/kg。结果表明:①Ⅰ组能显著降低小鼠肝脏中硒的沉积量(P<0.05);②Ⅰ组谷胱甘肽过氧化物酶1(glutathione peroxidase 1,GPx1)的mRNA相对表达量明显低于Ⅱ、Ⅲ组(P<0.05),且Ⅱ、Ⅲ组在肝脏中差异显著(P<0.05),在睾丸中差异不显著(P>0.05);③Ⅰ、Ⅲ组肝脏中谷胱甘肽过氧化物酶4(glutathione peroxidase 4,GPx4)的mRNA相对表达量差异不显著(P>0.05),但均显著低于Ⅱ组(P<0.05),而各试验组间在睾丸中差异均不显著(P>0.05);④随着日粮中硒添加量的增加,肝脏和睾丸中硫氧还蛋白还原酶2(thioredoxin reductase 2,TrxR2)的mRNA相对表达量显著提高(P<0.05)。因此,在肝脏和睾丸组织中,饲喂低硒饲料能显著降低硒的沉积量和GPx1、GPx4、TrxR2的mRNA相对表达量(P<0.05);而饲喂高硒饲料能显著降低GPx1的mRNA相对表达量(P<0.05),同时显著增加TrxR2的mRNA相对表达量(P<0.05)。提示,硒对GPx1、GPx4和TrxR2 mRNA相对表达量的调节存在组织差异性。     

硒源与硒水平对军曹鱼幼鱼生长性能、肝脏和血清抗氧化指标及组织硒含量的影响

本试验旨在研究硒源和硒水平对军曹鱼幼鱼生长性能、肝脏和血清抗氧化指标及组织硒含量的影响,以确定军曹鱼幼鱼对不同硒源的最适需要量。在基础饲料中分别添加0(对照)、0.3、0.6、0.9和1.2 mg/kg(以硒计)的亚硒酸钠(Se-S)或蛋氨酸硒(Se-Met),配制9种试验饲料(共用对照饲料),饱食投喂初始体重为(22.18±0.35)g的军曹鱼幼鱼10周。每种试验饲料投喂3个网箱(重复),每个网箱放养30尾试验鱼。结果表明:1)硒水平对特定生长率(SGR)和增重率(WGR)有极显著影响(P0.01),但对成活率(SR)和饲料系数(FCR)无显著影响(P0.05);硒源及硒源与硒水平的交互作用对SGR、W GR、FCR和SR均无显著影响(P0.05)。SGR和W GR随着硒水平的升高先升高后降低。2)硒水平极显著影响肝脏谷胱甘肽过氧化物酶(GSH-Px)、谷胱甘肽还原酶(GR)活性和丙二醛(MDA)含量及血清GSH-Px活性(P0.01),并显著影响血清GR活性(P0.05);硒源极显著影响肝脏GR、总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)活性和MDA含量及血清T-SOD活性(P0.01);硒源和硒水平的交互作用显著影响肝脏CAT活性和MDA含量及血清T-SOD活性(P0.05)。肝脏和血清GSH-Px活性随着硒水平的升高呈先升高后稳定趋势,GR活性呈先下降后稳定趋势。2种硒源均在添加量为0.9 mg/kg时有最高的肝脏GSH-Px活性,最低的肝脏GR活性。肝脏CAT活性随着硒水平的升高逐渐升高。3)脊椎骨、全鱼和肝脏硒含量随硒水平的升高而增加。硒源极显著影响脊椎骨硒含量(P0.01),硒源和硒水平的交互作用极显著影响肝脏和脊椎骨硒含量(P0.01)。以蛋氨酸硒和亚硒酸钠为硒源,通过二次回归曲线分析得出饲料硒水平分别为1.29和1.46 mg/kg时军曹鱼幼鱼可以获得最大SGR。以SGR和全鱼硒含量为判据,军曹鱼幼鱼对蛋氨酸硒的生物利用率分别相当于亚硒酸钠的1.20和2.90倍。     

Excretion of Selenium in the Milk of Sheep

The excretion of selenium in milk was investigated in twelve ewes. Four of these were injected 12–29 days before, and four immediately after delivery, with Se⁷⁵-sodium selenite. One month after delivery two ewes were injected with Se⁷⁵-selenomethionine, and two with Se⁷⁵-sodium selenite. The Se⁷⁵-concentration was measured in the milk and its various fractions as well as in the plasma, whole blood and organs of three lambs.The excretion of Se⁷⁵ into the milk was markedly higher when Se⁷⁵-selenomethionine was administered than when Se⁷⁵-sodium selenite was given. The amount of Se⁷⁵ in the various milk fractions was, to a great extent, proportional to the amount of protein in the fractions; this applied to the administration of organic as well as inorganic selenium. The highest Se⁷⁵-concentration in the milk was obtained already within 24 hours after injection. Selenium administered before delivery gave the highest concentration in samples taken less than six hours after delivery. The lambs which received Se⁷⁵ via the milk had a higher content of Se⁷⁵ than those who received it during the fetal period.     

Excretion of A Single Dose of Selenium in Sheep

The excretion of Se⁷⁵ via the feces and urine was studied in 30 sheep. Se⁷⁵-sodium selenite was injected subcutaneously, using three different doses ranging from a tracer dose to a therapeutic dose. By the intraruminal route the substance was given in a tracer dose and a therapeutic dose. Se⁷⁵-selenomethionine was injected subcutaneously and intraruminally in a tracer dose. Se⁷⁵-selenocystine was given intravenously in a dose higher than that regarded as a therapeutic dose.After intraruminal injection a higher percentage of the dose was excreted via the feces than via the urine. After the two highest subcutaneous doses the urinary excretion was significantly higher than the fecal excretion. After a high selenium dose the percentage eliminated via the urine was greater than after a low dose, whether the subcutaneous or the intraruminal route was used.The fecal and urinary excretion of Se⁷⁵ was of approximately the same order after injection of Se⁷⁵-selenomethionine and Se⁷⁵-selenocystine as after injection of the tracer dose of Se⁷⁵-sodium selenite.In 2 sheep, 1.4 per cent and 3.7 per cent, respectively, of a therapeutic dose were excreted via the bile in 48 hours.Less than 3 per cent of a subcutaneous dose was eliminated with the expired air in 24 hours.Exactly how much of a therapeutic dose is excreted within, for instance, 2 weeks is difficult to establish, as the treated animal’s selenium supply with the feed is not known. In the experiments reported here, however, approximately 64 per cent of a subcutaneous and 75 per cent of an intraruminal therapeutic dose were excreted over a two-week period.     

Effect of Parenteral Selenium Administration to Sheep on Prevalence and Recovery from Footrot

Background: Insufficient intake of selenium (Se) is common in many regions, and can contribute to increased susceptibility to and prolonged recovery from infectious diseases. Objective: To determine the effect of Se administration in decreasing the severity and prevalence of footrot in sheep. Animals: Thirty‐eight footrot‐affected and 19 nonaffected sheep from a commercial flock of known high incidence of footrot. Methods: Placebo‐controlled, prospective, 15‐month clinical trial. Footrot‐affected sheep were randomly assigned into 2 groups (n = 19) and injected with either 5 mg Se (footrot [FR]‐Se) or saline (FR‐Sal) at 1‐month intervals for the duration of the study. Unaffected sheep (controls) received no treatment. Sheep feet were examined, trimmed, and scored for footrot with a scale of 0 (no footrot) to 4 (extensive) at 0, 3, 6, 9, and 15 months. Sheep were also bled at time 0 and then at 3, 6, and 15 months to assess whole blood Se concentrations. Results: At time 0, control sheep (255 ± 11 ng/mL) had higher (P < .05) whole blood Se concentrations compared with FR‐Se (205 ± 12 ng/mL) and FR‐Sal (211 ± 14 ng/mL) sheep. By 6 months, FR‐Se sheep (317 ± 9 ng/mL) had whole blood Se concentrations greater (P < .05) than both control (281 ± 14 ng/mL) and FR‐Sal (277 ± 16 ng/mL) sheep. FR‐Se ewes showed a faster decline in highest lesion score at 3 (P= .012) and 6 (P= .0036) months, and a greater decrease in the number of feet with foot score >0 at 6 (P= .020) months compared with FR‐Sal ewes. Sheep with blood Se concentrations <300 ng/mL were at 3.5 times greater risk (1.1–12.1 confidence interval, odds ratio) for FR, although this relationship was only significant (P= .04) at 6 months of the study. Conclusions and Clinical Importance: In sheep with footrot, improved Se status in conjunction with routine control practices result in more rapid improvement of foot lesions.     

中国北方放牧绵羊硒的营养状况和季节变化

通过对我国４省区１５个牧场３００只放牧绵羊血浆和粪硒含量的采集和分析发现，在全年的部分时间，甘肃省的各个牧场和新疆的巩乃斯羊场均存在着硒的供给不足。此种现象在夏季和秋季表现最为明显，而此时动物和牧草生长最快。此时若不给予适量的硒，很容易使动物产生硒缺乏。对羔羊尤其需要引起注意，即使在夏季草场放牧时，也需给羔羊补硒     

高铜日粮对肉鸡肝脏Trx2蛋白表达的影响

将200羽1日龄Cobb商品代肉鸡随机分为4组,各组日粮中铜含量分别为:对照组(Ⅰ组)11 mg/kg、试验Ⅱ组110 mg/kg、试验Ⅲ组330 mg/kg、试验Ⅳ组550 mg/kg。饲养至10、30、50 d时每组各取5只鸡用于采集肝脏样品,提取肝脏总RNA用RT-PCR法测定Trx2基因m RNA在肝脏中的表达量,用蛋白质印迹法检测Trx2蛋白表达量。结果显示:日粮铜含量为11 mg/kg、110 mg/kg和330 mg/kg时,随着试验时间的延长,肝脏Trx2基因表达升高,但差异不显著(P0.05),而铜含量为550 mg/kg时,Trx2基因表达量降低且50 d时差异显著(P0.05);随着试验时间的延长,各试验组的Trx2蛋白表达量均升高,且330 mg/kg和550 mg/kg组在50 d时差异显著(P0.05)。试验表明,饲喂高铜日粮可导致线粒体型硫氧还蛋白2(Trx2)mRNA在肝脏中的表达量先升高后降低,蛋白表达量升高。     

半定量RT-PCR法分析猪肝脏中铜锌超氧化物歧化酶mRNA表达水平

细胞内铜锌超氧化物歧化酶（CuZnSOD）是动物体内一种重要的抗氧化酶。本实验室构建了优化的半定量RT-PCR法，以18S rRNA为内标，研究猪肝脏组织中CuZnSOD基因mRNA表达水平。提取猪肝脏组织总RNA，经反转录后进行扩增，先寻求PCR线性扩增范围，确定RT．PCR的最佳循环数和Mg^2＋浓度。扩增后用VDS摄像系统扫描PCR扩增产物的电泳条带灰度。通过CuZnSOD PCR产物的灰度与18S rRNA PCR产物的灰度之比，即可计算出CuZnSOD mRNA的相对含量。