Zinc, copper and iron utilisation by chicks fed various concentrations of zinc

1. Zinc, iron and copper interactions were examined in chicks (New Hampshire X Single Comb White Leghorn) grown individually in stainless steel cages and fed on purified diets with three concentrations of zinc: control (37 mg Zn/kg), moderate (100 mg Zn/kg) and excess (2000 mg Zn/kg) in three studies. 2. Chicks given either moderate or excess zinc excreted more than twice as much 65Zn from a test diet as those fed on the control diet. Thus chicks given the moderate amount of zinc had concentrations of zinc in tissues similar to those of controls but chicks given excess zinc accumulated zinc in their tissues. 3. The specific activity of 65Zn in the tissues, especially in the bursa of Fabricius, of chicks given excess zinc was not reduced as much as would be predicted. Thus, ingestion of excess zinc appeared to reduce tissue turnover of 65Zn, especially in the bursa. However, humoral immune responses, as measured by antibody titres to sheep red blood cells, were not affected. 4. Chicks given excess zinc or pair-fed on the control diet retained less 59Fe from a test diet than chicks given control or moderate concentrations of zinc ad libitum. The iron concentrations in tibiae of chicks given excess zinc were depressed.     

饲料铜水平对雏鸡组织器官中铜、铁、锌含量的影响

将80只1日龄艾维菌肉仔鸡随机分成4组,每组4个重复,每个重复5只鸡,对照组喂基础日粮,试验组在基础日粮中分别添加硫酸铜10、50 mg/kg和100 mg/kg,试验期21 d.试验结果表明:随日粮铜添加水平的增加,肝脏、胫骨中铜含量有所增加,尤其是铜添加量为100 mg/kg时,肝脏、胫骨中铜含量都显著高于对照组(P＜0.05).肝脏、胫骨中铁含量随铜添加水平的升高而逐渐下降.肝脏、胫骨中锌含量也随铜添加水平的变化而变化.     

Adhesive properties and iron uptake ability in Escherichia coli lethal and nonlethal for chicks

Escherichia coli that are virulent for poultry usually result in a respiratory disease, which is frequently followed by a general infection. Adhesiveness of E. coli to epithelial cells and iron-uptake ability of E. coli could be involved in different steps of the disease. These properties were studied in 59 E. coli strains originating from poultry, with reference to lethality for day-old chicks. Adhesive properties were found in 64% of the lethal strains and in only 23% of the nonlethal strains. The ability to grow in limited iron conditions was strongly correlated with lethality. Fifty-two percent of the lethal E. coli strains, but none of the nonlethal strains, possessed both adhesive and iron-uptake abilities. It is suggested that these two properties play a role in the virulence of E. coli for poultry.     

The effects of intestinal Escherichia coli 263, intravenous infusion of Escherichia coli 263 culture filtrate and iron dextran supplementation on iron metabolism in the young pig

An experiment using 32 pigs in a 2(3) factorial arrangement of treatments was used to determine the effects on the (1) level of iron dextran supplementation, (2) iv infusion of an Escherichia coli 263 culture filtrate and (3) presence of E. coli 263 in a ligated intestinal segment, on the ability of the young pig to limit systemic Fe availability. Iron dextran was administered im 3 d postpartum. Culture filtrate was infused iv, E. coli were injected into ligated intestines and blood sampling was started at 14 d postpartum. Blood was taken every 2 h for 22 h, after which pigs were euthanized and livers, spleens and kidneys were removed. Pigs receiving 400 mg of iron dextran (HiFe) exhibited greater serum Fe (SFe) and lower total Fe-binding capacity (TIBC) than pigs injected with 100 mg Fe (LoFe). The effects of the E. coli culture filtrate infusion appeared to be associated with endotoxin-induced circulatory shock. The presence of E. coli in the intestine increased TIBC in LoFe pigs, but not in HiFe pigs. The increase in TIBC coincided with the time of maximal fluid secretion into the intestine. Intestinal E. coli also caused an increase in liver Fe content, particularly in HiFe pigs. These data suggest that intestinal E. coli can cause a shift of Fe from the plasma to the reticuloendothelial system, and pigs receiving high supplemental dosages of Fe are less able to limit the availability of Fe to microorganisms.     

Effects of exogenous iron on Escherichia coli septicemia of turkeys

The effect of inoculation with Escherichia coli on serum iron concentrations of turkeys and the effect of exogenous iron, as ferric ammonium citrate, on E coli septicemia in turkeys were determined. Inoculation of air sacs with E coli produced hypoferremia in 18-day-old turkeys. Administration of iron with E coli significantly (P less than 0.01) increased mortality, frequency and degree of bacteremia, and severity of lesions in inoculated turkeys, compared with those in turkeys given E coli but not given iron. Similar results were seen whether iron was inoculated at the same location as E coli or at a different location.     

猪日粮中铜、铁、锰、锌减量使用技术研究进展

微量元素在猪的生长发育、生产繁殖、健康免疫等方面有重要的作用,生产实际中为某种目的经常会在饲料中添加超出猪生理需求剂量的微量元素。然而,长期过量的微量元素使用会带来一系列的负面影响。本文旨在对猪日粮中铜、铁、锰、锌使用的现状、过量添加的负面影响及减量使用的技术措施进行综述,以期为微量元素的有效、合理使用,保护环境提供参考。     

微生物发酵铁、锌、锰、铜对蛋鸡生产性能和血清指标的影响

选用2 000只380日龄海兰褐蛋鸡,随机分为5组,每组4个重复,每个重复100只鸡,对照组饲喂由无机微量元素(硫酸盐类)配制的基础日粮,试验1,2,3,4组分别饲喂由酵母菌、乳酸菌、酵母菌+乳酸菌以及酵母菌+乳酸菌+枯草芽孢杆菌等单一和复合菌种发酵后的微量元素配制的日粮,研究微生物发酵微量元素对蛋鸡生产性能和血清指标的影响,试验期40d。结果显示,与对照组相比,试验3,4组产蛋率显著提高(P0.05);试验2,3,4组料蛋比显著降低(P0.05);各发酵组均显著降低了蛋鸡破损蛋率(P0.05)和死淘率(P0.05)。发酵微量元素对鸡蛋常规蛋品质和蛋成分指标有一定改善作用,其中试验3,4组显著提高了蛋壳厚度(P0.05);试验2,3,4组鸡蛋胆固醇显著降低(P0.05)。各发酵微量元素组和对照组蛋鸡血清生化指标无显著性差异。结果表明,发酵微量元素对蛋鸡生产性能、蛋品质、蛋成分均有不同程度的改善效果,其中复合菌发酵优于单一菌发酵。     

Tolerance for excess basic zinc chloride and basic copper chloride in chicks

(1) Four chick experiments were conducted to determine toxicity estimates for basic zinc chloride (BZC) and basic copper chloride (BCC), now being used as sources for these minerals. (2) In experiment 1, New Hampshire x Columbian crossbred chicks were fed 0, 500, 1000, 1500, 3000 and 5000 mg Zn/kg from BZC (Zn5Cl2(OH)8). Broken-line regression analysis showed that the minimal toxic break points for chick weight gain and gain:food were 1720 and 2115 mg Zn/kg, respectively. (3) Crossbred chicks were fed 0, 150, 250, 500, 750 and 1000 mg Cu/kg from BCC (Cu2(OH)3C) in experiment 2. Regression analysis indicated that the minimal toxic break points for chick weight gain and gain:food were 642 and 781 mg Cu/kg, respectively. (4) In experiment 3, commercial broiler chicks were fed 0, 1500, 2000 and 2500 mg supplemental Zn/kg from BZC or 0, 500, 650 and 800 mg supplemental Cu/kg from BCC. Broiler chicks fed those high inclusion rates of Zn did not show reduced weight gain in comparison to chicks fed no supplemental Zn. All high concentrations of supplemental Cu depressed chick weight gain in comparison to control chicks. (5) Experiment 4 involved two separate 4 x 2 factorial designs with supplemental Zn (0, 2500, 3500 and 4500 mg/kg) or Cu (0, 500, 750 and 1000 mg/kg) and two breeds of chicks (crossbred and commercial). Significant interactions for weight gain, food intake, gain:food and liver Cu suggested that the crossbred and commercial chicks responded differently to high concentrations of supplementary dietary Cu.     

Renal lesions and tissue concentrations of zinc, copper, iron and manganese in experimentally zinc intoxicated sheep

Renal lesions were produced in three out of 10 sheep dosed with large quantities of zinc for two to 14 weeks. Administration of the zinc resulted in significant increases in the concentrations of zinc in the kidneys, liver and pancreas, and of copper and iron in the kidneys and pancreas, and a significant decrease in the concentration of manganese in the pancreas. The sheep with kidney damage had increased plasma creatinine concentrations and significantly higher mean concentrations of zinc in their livers and pancreases, and of copper and iron in their kidneys, than the sheep with no kidney damage.     

羟基蛋氨酸铁、铜、锰、钵螯合率的测定

氨基酸微量元素螯合物的生物利用率比无机离子的利用率高2～3倍,使用氨基酸微量元素螯合物是解决过量添加无机盐造成环境污染这一难题的有效方法,同时也防止了无机盐产生的不良影响及对维生素的拮抗作用.     

Effects of copper sulfate, tri-basic copper chloride, and zinc oxide on weanling pig performance

Three experiments were conducted to evaluate the effects of increasing dietary Cu and Zn on weanling pig performance. Diets were fed in 2 phases: phase 1 from d 0 to 14 postweaning and phase 2 from d 14 to 28 in Exp. 1 and 2 and d 14 to 42 in Exp. 3. The trace mineral premix, included in all diets, provided 165 mg/kg of Zn from ZnSO(4) and 16.5 mg/kg of Cu from CuSO(4). In Exp. 1, treatments were arranged in a 2 × 3 factorial with main effects of added Cu from tri-basic copper chloride (TBCC; 0 or 150 mg/kg) and added Zn from ZnO (0, 1,500, or 3,000 mg/kg from d 0 to 14 and 0, 1,000, or 2,000 mg/kg from d 14 to 28). No Cu × Zn interactions were observed (P > 0.10). Adding TBCC or Zn increased (P < 0.05) ADG and ADFI during each phase. In Exp. 2, treatments were arranged in a 2 × 3 factorial with main effects of added Zn from ZnO (0 or 3,000 mg/kg from d 0 to 14 and 0 or 2,000 mg/kg from d 14 to 28) and Cu (control, 125 mg/kg of Cu from TBCC, or 125 mg/kg of Cu from CuSO(4)). No Cu × Zn interactions (P > 0.10) were observed for any performance data. Adding ZnO improved (P < 0.02) ADG and ADFI from d 0 to 14 and overall. From d 0 to 28, supplementing CuSO(4) increased (P < 0.02) ADG, ADFI, and G:F, and TBCC improved (P = 0.006) ADG. In Exp. 3, the 6 dietary treatments were arranged in a 2 × 2 factorial with main effects of added Cu from CuSO(4) (0 or 125 mg/kg) and added Zn from ZnO (0 or 3,000 mg/kg from d 0 to 14 and 0 or 2,000 mg/kg from d 14 to 42). The final 2 treatments were feeding added ZnO alone or in combination with CuSO(4) from d 0 to 14 and adding CuSO(4) from d 14 to 42. Adding ZnO increased (P < 0.04) ADG, ADFI, and G:F from d 0 to 14 and ADG from d 0 to 42. Dietary CuSO(4) increased (P < 0.004) ADG and ADFI from d 14 to 42 and d 0 to 42. From d 28 to 42, a trend for a Cu × Zn interaction was observed (P = 0.06) for ADG. This interaction was reflective of the numeric decrease in ADG for pigs when Cu and Zn were used in combination compared with each used alone. Also, numerical advantages were observed when supplementing Zn from d 0 to 14 and Cu from d 14 to 42 compared with all other Cu and Zn regimens. These 3 experiments show the advantages of including both Cu and Zn in the diet for 28 d postweaning; however, as evident in Exp. 3, when 3,000 mg/kg of Zn was added early and 125 mg/kg of Cu was added late, performance was similar or numerically greater than when both were used for 42 d.     

铜锌元素代谢病的生物学研究进展

铜、锌是动物机体所必需的营养元素,具有催化、构建和调节等三种基本的生物学功能.研究细胞内外微量元素的潴留、转运、特异分布等生物代谢乃至分子水平的基因表达过程将为深入地揭示元素的转运机制、生物效能和代谢疾病的病理学机制提供理论依据,为微量元素疾病的早期防治和营养补给提供科学的指导.笔者等将有关铜、锌元素细胞(分子)生物学和酶学方面的最新研究进行概述. 1 铜、锌元素生物催化作用的酶学机制 动物体内微量元素铜、锌在动物机体中的生物学功能与其相关酶结构的组成和活力密切相关,通过对相关酶或生物膜位点的"占领"发挥其正常的生物学功能.     

Effects of altered dietary iron intake in Mycobacterium paratuberculosis-infected dairy cattle: sequential observations on growth, iron and copper metabolism and development of paratuberculosis

Twenty calves were orally inoculated with Mycobacterium paratuberculosis at six weeks old. At six months old, 10 of these, plus four uninfected controls were maintained on limited dietary copper and supplemented iron intake for a further 27 months. During this time all these animals, together with a further four untreated controls, were bred before being killed and examined for evidence of paratuberculosis. Despite significant reduction in weight gain, attributable to both iron supplementation and infection, no significant difference was found in the numbers of iron-supplemented and unsupplemented animals that developed clinical signs nor in the extent and severity of intestinal lesions between groups. Accumulation of iron in paratuberculosis lesions was not affected by iron supplementation but was positively correlated with the frequency of shedding of M paratuberculosis in faeces (P less than 0.05). Dietary iron supplementation alone resulted in serum hyperferraemia, hepatic siderosis and slight hypocuprosis, whereas, in infected animals, this resulted in marked hypocuprosis and anaemia within groups (P less than 0.05). Infection alone resulted in serum hypoferraemia and intestinal and hepatic siderosis which was positively correlated with the severity of infection within groups (P less than 0.05). Susceptibility to paratuberculosis may result from failure ultimately to limit monokine-mediated iron sequestration in intestinal tissue.     

Copper, zinc and iron levels in the cerebrospinal fluid of copper poisoned sheep

Copper, zinc and iron levels were measured in cerebrospinal fluid (CSF) of normal and copper poisoned sheep. Copper values were within the range recorded for humans but zinc levels were six to 20 times and iron levels were 20 to 30 times higher than values reported for humans. The amount of copper, zinc and iron in the CSF did not increase in sheep dosed with copper and hence it is unlikely that the level of copper in the CSF is related to the changes in the nervous system that have been reported in copper poisoned sheep.     

日粮锌源和锌水平对断奶仔猪血清及组织铜、铁、锌沉积的影响

选用临床检查健康的(26±2)日龄"杜×长×大"三元杂交断奶仔猪100头,按体质量和性别随机分为5组,每组20头,分别饲喂基础日粮、基础日粮+2000mg/kg氧化锌、基础日粮+3000mg/kg氧化锌、基础日粮+250mg/kg蛋氨酸锌、基础日粮+500mg/kg蛋氨酸锌。试验期14d。于断奶后0,7,14d,经前腔静脉采血,用原子吸收光谱仪检测血清中铜、铁、锌水平。试验结束时,每组选5头仔猪放血致死,取心、肝、肾、脑、脾、胸腺组织,测定铜、铁、锌含量。结果显示,仔猪断奶后,血清中铜、锌水平显著或极显著下降(P0.05或P0.01);添加不同锌源和锌水平的高锌日粮能提高断奶仔猪肝、肾、脑、血清锌的含量,显著或极显著降低仔猪血清铜和心、胸腺铜以及脾铁水平(P0.05或P0.01),对血清铁及其他组织铁含量无明显影响。这表明高锌日粮能增加断奶应激仔猪体内锌水平,降低部分组织中铜、铁含量。     

动物铁、铜、锌、硒代谢及缺乏症研究新进展

微量元素铁、铜、锌、硒在动物生命活动中其中非常重要的作用,缺乏可导致动物患发一系列的病症。动物缺铁可导致其生长发育受阻及免疫力降低;铜缺乏时可有被毛稀疏、粗糙、缺乏光泽、弹性降低、颜色变浅等症状;缺锌时可表现鼻镜干燥,爪垫增厚或龟裂,被毛发育不良、易断;硒缺乏可表现被毛粗糙,骨骼肌变性、退色。     

Effect of tetrathiomolybdate administration on the excretion of copper, zinc, iron and molybdenum in sheep bile

The copper (Cu), zinc (Zn), and iron (Fe) excreted daily in the bile of three sheep were estimated at 0.20, 0.10 and 0.36 mg respectively. Intravenous administration of tetrathiomolybdate (TM) increased bile Cu excretion and reduced liver Cu concentration. Tetrathiomolybdate had no significant effect on the excretion of Zn and Fe. These findings indicate that at least one of the mechanisms by which TM induces hypocuprosis is by increasing biliary Cu excretion. Hence it has a possible use in the treatment of Cu storage diseases in man and animals.     

Effects of growth hormone on tissue metabolism in broiler chicks.

1. The effect of bovine growth hormone (GH) on cartilage, liver, muscle, pancreas and spleen has been investigated. 2. Tissue RNA was elevated in the liver, muscle and spleen of the GH-treated chicks while uptake of radioactive phosphate into RNA was stimulated for both liver and spleen. 3. The GH-treated chicks had an increased cartilage protein content together with a higher rate of incorporation of 14C-methionine pancreatic protein.