蛋氨酸螯合锌和无机锌对仔猪生产性能的比较

将96头三元杂交仔猪分为4个组，在基础日粮上分别添加：1组为蛋氨基酸螯合锌350mg(锌）／kg、2组为氧化锌3000mg（锌）/kg、3组为氧化锌60mg（锌）／kg＋蛋氨基酸螯合锌40mg(锌）／kg、对照组为氧化锌100mg(锌）/kg。结果表明：1、2、3组较对照组日增重、日采食量、饲料利用率高。1组与2组日增重、日采食量、饲料利用率、腹泻发生率几方面差异不显（P＞0．05）。     

高铜、高锌水平预混料对断奶仔猪促生长防下痢效果比较

将54头三元杂交断奶仔猪设3个处理 ,每个处理6个重复 ,每个重复3头猪。3个处理试验猪分别饲以高铜日粮(250mg/kgCu +100mg/kgZn)、高锌日粮(16mg/kgCu +3000mg/kgZn)、正常铜锌日粮(16mg/kgCu +100mg/kgZn)。高铜日粮组、高锌日粮组、正常铜锌日粮组试验猪日增重分别为 :237g、276g、211g,高锌处理对仔猪的促生长作用较高铜和正常铜锌处理为好 ;试验猪饲料采食量、饲料转化率最高 ,腹泻率最低 ;高铜处理和正常铜锌处理次之     

甘氨酸锌对断奶仔猪生长性能及皮毛指标的影响

试验选用体重9.8 kg左右的仔猪为试验动物,随机分为2个处理组。对照组在基础日粮中添加80 mg/kg的硫酸锌,试验组添加80 mg/kg的甘氨酸锌。每个处理组设6个重复,每个重复8头,共计96头仔猪。经21 d的饲养试验,研究不同锌源对断奶仔猪生长性能及皮毛指标的影响。结果表明:仔猪日粮中添加甘氨酸锌能够显著提高断奶仔猪的平均日采食量、日增重,降低料肉比,且能显著改善皮毛感官指标。     

高铜、锌水平预混料对断奶仔猪促生长防下痢效果比较

54 头三元杂交断奶仔猪设3 个处理,每个处理6 个重复,每个重复3 头猪。3 个处理试验猪分别饲以高铜日粮(250 mg/kgCu 100 mg/kgZn) 、高锌日粮(16 mg/kgCu 3 000 mg/kgZn)、正常铜锌日粮(16 mg/kgCu 100 mg/kgZn)。高铜日粮组、高锌日粮组、正常铜、锌日粮试验猪日增重分别为:237 、276、211 g,高锌处理对仔猪的促生长作用较高铜和正常铜、锌处理为好;试验猪饲料采食量、饲料转化率最高,腹泻率最低;高铜处理和正常铜、锌处理次之。     

日粮蛋氨酸螯合锌和硫酸锌水平对肉仔鸡生产性能的影响

试验探讨了日粮中不同硫酸锌和蛋氨酸螯合锌水平对肉用仔鸡生产性能、血液生化指标和胫骨锌及铁浓度的影响.选用1日龄岭南黄肉鸡720只,按体重和性别随机分为6组,每组4个重复,每个重复30只鸡.在玉米豆粕型基础日粮中分别以硫酸锌和蛋氨酸螯合锌形式添加40、80和120mg/kg锌饲喂试验鸡,预饲10d,正式试验期为21 d.结果表明,日粮锌源和锌水平对肉仔鸡平均日增重、平均日采食量、血清碱性磷酸酶活性、血清葡萄糖和总蛋白浓度以及胫骨锌和铁含量无明显影响,在锌添加水平为40mg/kg时,蛋氨酸螯合锌处理组耗料增重比显著低于硫酸锌组(P<0.05).     

包被氧化锌对防治断奶仔猪腹泻的影响与功效

试验旨在研究包被氧化锌对防治断奶仔猪腹泻的影响及功效。试验选取48头25日龄断奶,窝别不同、体质均匀,体重约7.4 kg的健康二元杂种仔猪,随机分为2个处理,每个处理3个重复,每个重复8头猪。处理1组为在基础日粮上添加3 000 mg/kg普通氧化锌,处理2组为在基础日粮上添加100 mg/kg包被氧化锌。试验期为14 d,在第7 d和14 d分别称重,按天统计采食量(以重量为单位),并每天观察、记录仔猪发病、腹泻和死亡等情况,计算平均日增重(ADG)、平均日采食量(ADFI)、料重比(F/G)、腹泻频率。结果显示,在断奶仔猪日粮中添加包被氧化锌和普通氧化锌在提高仔猪的日增重、日采食量和料重比方面无明显差异;包被氧化锌比普通氧化锌能更好地提高饲料的利用率;在控制腹泻方面,添加100 mg/kg包被氧化锌对于断奶后2周仔猪的腹泻率的作用与添加3 000 mg/kg普通氧化锌类似,因此可以替代使用,以减小其引起的副作用。     

氧化锌与纳米氧化锌对断奶仔猪生长性能和锌利用率的影响

文章旨在研究饲粮添加普通氧化锌和纳米氧化锌对断奶仔猪生长性能、腹泻率以及锌利用率的影响。试验将200头断奶仔猪平均分为对照组、400mg/kg氧化锌组和200mg/kg纳米氧化锌组、400mg/kg纳米氧化锌组和600mg/kg纳米氧化锌组。结果发现,与对照组相比,日粮添加不同形态、不同剂量的氧化锌均能显著提高断奶仔猪日增重、日采食量和锌的利用率（P <0.05）,显著降低料重比（P <0.05）。结果表明,日粮中添加纳米氧化锌可显著促进仔猪生长,提高仔猪免疫力,且纳米氧化锌添加量为400mg/kg效果最佳,具有替代高剂量普通氧化锌的潜力。     

纳米氧化锌对仔猪生产性能和粪便微生物群落的影响

采用单因子试验设计,选80头平均体重为8．1 kg的杜×长×大仔猪随机分配到10个处理中,每个处理4个重复(圈)。研究纳米氧化锌对仔猪生产性能、腹泻率和粪便中微生物活菌数量的影响。试验设4个对照组:基础日粮组、基础日粮分别添加100、2 500 mg/kg饲料级氧化锌和100 mg/kg硫酸锌组,6个试验组:基础日粮中分别添加50、 100、500、1 000、1 500、2 500 mg/kg的纳米氧化锌,试验期42 d。结果表明:①试验1-2周,2 500 mg/kg纳米氧化锌显著提高仔猪平均日增重(ADG)和平均日采食量(ADFI)(P<0．05),提高饲料利用率(P>0．05);试验全期50 mg/kg 纳米氧化锌组的ADG、ADFI和平均末重均高于其余各个处理组。②添加2 500 mg/kg的高剂量锌极显著降低腹泻率(P<0．01),纳米氧化锌降低腹泻的效果优于其他锌源。③2 500mg/kg高剂量锌显著降低粪便中大肠杆菌数(P< 0．05);纳米氧化锌对大肠杆菌的抑茵效果优于饲料级氧化锌和硫酸锌。     

甘氨酸锌对断奶仔猪生长性能、免疫指标及肠道形态的影响

本文旨在研究甘氨酸锌对断奶仔猪生长性能、免疫指标和肠道形态的影响.选用150头28日龄的杜×长×大三元杂交断奶仔猪,分成5组(每组3个重复,每个重复10头),对照组饲喂基础日粮,试验组饲喂分别在基础日粮中添加50、100和200 mg/kg甘氨酸锌(以锌计)和3 000 mg/kg氧化锌(以锌计)的日粮.饲养期为35 d.结果表明:与对照组相比,100 mg/kg的甘氨酸锌组和3 000 mg/kg的氧化锌组极显著提高了仔猪的日增重(P<0.01);100 mg/kg的甘氨酸锌组和3 000 mg/kg的氧化锌组的胰脏指数、淋巴结指数、血清中IgG、IgM、补体C3和补体C4水平以及十二指肠的绒毛高度都显著高于对照组(P<0.05),其中100 mg/kg甘氨酸锌组还显著降低了空肠的隐窝深度(P<0.05).结果提示,饲料中添加甘氨酸锌能够促进断奶仔猪生长、提高断奶仔猪的免疫机能.     

纳米氧化锌对断乳仔猪生长性能和粪锌排泄量的影响

选用15头断乳仔猪，分为处理1组（3000mg／Kg普通饲料级氧化锌）、处理2组（250mg/Kg纳米氧化锌）、处理3组（500mg／kg纳米氧化锌）三个处理，每个处理5个重复，每个重复1头仔猪，试验期20d。结果表明：处理3组的日增重分别比处理1组和处理2组提高5．41％和8．33％，处理3组和处理1组之间差异不显著，而处理3组和处理2组之间差异显著（黔0．05），改善肉料比。处理2组和处理3组的粪锌排出量比处理1组分别降低91．47％、82．85％。处理3组有较好的经济效益。     

Bioavailability of zinc in several sources of zinc oxide, zinc sulfate, and zinc metal.

Three zinc depletion-repletion assays were carried out with chicks to determine Zn bioavailability in five sources of ZnO, three sources of ZnSO4.H2O, and two sources of Zn metal. A standard 23% CP corn-soybean meal diet was fed during the first 3 d posthatching, after which it was replaced with a Zn-deficient soy concentrate diet (13.5 mg Zn/kg) until d 7. On d 8 after an overnight period of feed withdrawal, chicks were fed for 12 d the Zn-deficient basal diet containing 0, 4.76, and 9.90 (Assay 1); 0, 5.06, or 10.12 (Assay 2); or 0, 4.73, or 9.13 (Assay 3) mg/kg supplemental Zn from analytical grade (AG) ZnSO4.7H2O (22.7% Zn) to generate a standard response curve. The AG and feed-grade (FG) Zn sources being evaluated were then provided at a level that would fall within the standard curve. Weight gain (Assays 1, 2, and 3) and total tibia Zn (Assay 1) responded linearly (P<.01) to Zn supplementation from ZnSO4.7H2O. Weight gain regressed on supplemental Zn intake gave standard-curve equations with fits (r2) ranging from .94 to .97. In Assay 1, regression of total tibia Zn (Y, in micrograms) on supplemental Zn intake (X, in milligrams/12 d) gave the equation Y = 13.2+6.74X (r2 = .90). Standard-curve methodology was used to estimate relative Zn bioavailability (RBV), with RBV of Zn in the ZnSO4.7H2O standard set at 100%. Four sources of FG ZnO were evaluated: Source 1 (78.1% Zn, hydrosulfide process, U.S.), Source 2 (74.1% Zn, Waelz process, Mexico), Source 3 (69.4% Zn, China), and Source 4 (78.0% Zn, French process, Mexico). Analytical-grade ZnO (80.3% Zn) was also evaluated. Feed-grade ZnO Sources 1 and 4 as well as AG ZnO produced average RBV values that were not different (P>.10) from the standard, but average RBV values for FG Source 2 and FG Source 3 were only 34 (P<.05) and 46% (P<.05), respectively. All sources of ZnSO4.H2O, which included two FG sources (source 1, 36.5% Zn; source 2, 35.3% Zn) and one food-grade source (36.5% Zn), were not different (P>.10) in RBV from the ZnSO4.7H2O standard. Two Zn metal products, Zn metal dust (100% Zn) and Zn metal fume (91.5% Zn), were also evaluated, and they were found to have Zn RBV values of 67 (P<.05) and 36% (P<.05), respectively. Feed-grade sources of ZnO vary widely in color, texture, Zn content, and Zn bioavailability.     

Effect of bis-glycinate bound zinc or zinc sulfate on zinc metabolism in growing lambs

To assess the efficacy of bis-glycinate bound Zn, 36 crossbred wethers (34 ± 2 kg) were sorted by body weight into three groups and stagger started on a Zn-deficient diet (18 mg Zn/kg dry matter [DM]; 22.5% neutral detergent fiber [NDF]) for 45 d prior to a 15-d metabolism period (10 d adaptation and 5 d collection). On day 46, lambs were randomly assigned to dietary treatments (four lambs treatment⁻¹group⁻¹): no supplemental Zn (CON) or 15 mg supplemental Zn/kg DM (ZINC) as Zn sulfate (ZS) or bis-glycinate (GLY; Plexomin Zn, Phytobiotics). Blood was collected from all lambs on days 1, 44, 56, and 61. Liver, jejunum, and longissimus dorsi samples were collected after euthanasia on day 61. Gene expression was determined via quantitative real-time polymerase chain reaction. Data were analyzed using ProcMixed of SAS (experimental unit = lamb; fixed effects = treatment, group, and breed) and contrast statements assessed the effects of supplemental Zn concentration (ZINC vs. CON) and source (GLY vs. ZS). After 15 d of Zn supplementation, plasma Zn concentrations were greater for ZINC vs. CON and GLY vs. ZS (P ≤ 0.01); tissue Zn concentrations were unaffected (P ≥ 0.27). Liver Cu concentrations were lesser for ZINC vs. CON (P = 0.03). Longissimus dorsi Mn concentrations were greater for ZINC vs. CON (P = 0.05) and tended to be lesser for GLY vs. ZS (P = 0.09). Digestibility of DM, organic matter (OM), and NDF was lesser for ZINC vs. CON (P ≤ 0.05); acid detergent fiber digestibility tended to be greater for GLY vs. ZS (P = 0.06). Nitrogen retention (g/d) tended to be greater for GLY vs. ZS (P = 0.10), and N apparent absorption was lesser for ZINC vs. CON (P = 0.02). Zinc intake, fecal output, retention, and apparent absorption were greater for ZINC vs. CON (P ≤ 0.01). Apparent absorption of Zn was −5.1%, 12.8%, and 15.0% for CON, ZS, and GLY, respectively. Nitrogen and Zn retention and apparent absorption were not correlated for CON (P ≥ 0.14) but were positively correlated for ZINC (retention: P = 0.02, r = 0.52; apparent absorption: P < 0.01, r = 0.73). Intestinal expression of Zn transporter ZIP4 was lesser for ZINC vs. CON (P = 0.02). Liver expression of metallothionein-1 (MT1) tended to be greater for GLY vs. ZS (P = 0.07). Although Zn apparent absorption did not differ between sources (P = 0.71), differences in post-absorptive metabolism may be responsible for greater plasma Zn concentrations and liver MT1 expression for GLY-supplemented lambs, suggesting improved bioavailability of GLY relative to ZS.     

Uptake of zinc from zinc sulfate and zinc proteinate by ovine ruminal and omasal epithelia

Uptake and transport of Zn from (65)Zn-labeled ZnSO(4) and Zn proteinate (ZnProt) by ruminal and omasal epithelia were examined by using a parabiotic chamber system. Uptake was measured during a 4-h incubation with 10, 20, or 200 microM Zn as ZnSO(4) or ZnProt in the mucosal buffer (pH 6.0, Krebs-Ringer phosphate). Zinc uptake and transport were also evaluated after simulated ruminal digestion. Buffered ruminal fluid contained a feed substrate and 10 or 200 microM added Zn as ZnSO(4) or ZnProt. In a preliminary experiment, uptake of Zn by omasal tissue was low; thus, the remaining experiments were conducted solely with ruminal epithelium. Incubations to determine the effect of time on Zn uptake from mucosal buffer containing 20 microM added Zn as ZnSO(4) or ZnProt resulted in increased (P < 0.01) Zn uptake as incubation time increased from 30 to 240 min. Zinc uptake was also greater (P = 0.02) from mucosal buffer containing ZnProt compared with ZnSO(4). Zinc uptake from incubations containing 10 or 200 microM was affected by source x concentration (P = 0.05) and concentration x time (P < 0.01) interactions. With 10 microM Zn, uptake was not influenced by Zn source, whereas when 200 microM Zn was added, Zn uptake from ZnProt was greater than from ZnSO(4). Increasing incubation time resulted in increased Zn uptake with 200 microM Zn in the mucosal buffer; however, with 10 microM Zn, uptake did not change after 30 min. After simulated ruminal fermentation, the proportion of Zn in a soluble form was influenced by a source x concentration interaction (P = 0.03). After 18 h of incubation, the proportion of Zn that was soluble was not different between ZnProt and ZnSO(4) in buffered ruminal fluid that contained 10 microM added Zn, but was greater for ZnProt compared with ZnSO(4) with 200 microM Zn in the incubation. Zinc uptake from the aqueous fractions of simulated ruminal digestions containing 200 microM added Zn was greater (P < 0.01) than from those containing 10 microM added Zn. Zinc transport, based on detection of (65)Zn in serosal buffer, did not occur in any of the experiments. The results of the current experiments suggest that absorption of Zn into the bloodstream does not occur from the ruminant foresto-mach; however, Zn uptake occurs in ruminal tissue and is greater from ZnProt than from ZnSO(4).     

饲粮锌水平对肉鸡血锌、组织锌及含锌酶含量的影响

为研究饲粮中不同锌水平对某些含锌酶活性及血、胰和胫骨锌含量的影响,试验选择1日龄健康AA肉鸡公雏300只,随机分为5个处理组,各处理组锌的含量分别为30、60、90、120、150 mg/kg。结果表明:(1)21日龄时,120、150 mg/kg锌组血锌含量显著增加(P<0.05),与对照组相比,分别提高了56.75%和91.45%;150 mg/kg锌组胰锌含量显著增加(P<0.05),与对照组相比,提高了130.77%;90、120、150 mg/kg锌组胫骨锌含量显著增加(P<0.05),分别比对照组提高14.16%、19.50%和26.61%。42日龄时,150 mg/kg锌组血锌含量显著增加(P<0.05),比对照组提高77.25%;60、90、120 mg/kg锌组胰锌含量显著增加(P<0.05),分别比对照组提高194%、198%和212%;120、150 mg/kg锌组胫骨锌含量显著增加(P<0.05),分别比对照组提高37.80%和43.29%。(2)21日龄时,120、150 mg/kg锌组心肌金属硫蛋白(MT)含量显著增加,分别比对照组提高9.79%和32.17%;90、120、150 mg/kg锌组骨骼肌MT含量显著增加,分别比对照组提高54.55%、57.02%和90.91%。42日龄时,心肌和骨骼肌中的MT含量没有表现出显著的差异。(3)21日龄时,150 mg/kg锌组肝脏铜锌超氧化物歧化酶(CuZn-SOD)活性显著提高,42日龄时,150 mg/kg锌处理组肝脏CuZn-SOD活性显著低于其他处理组。在本试验条件下,饲粮中添加硫酸锌可以显著提高肉鸡血清、胰脏、胫骨组织中的锌沉积,并对肝脏CuZn-SOD活性有一定的影响。     

锌的生物学功能及有机锌的应用研究

锌是动物的必需元素,在动物机体代谢过程中起着重要的作用.本文综述了锌的生物学功能及有机锌的应用研究,包括有机锌的种类及在动物营养中的应用,并预测了今后有机锌的研究方向.     

Effects of dietary supplementation with tribasic zinc sulfate or zinc sulfate on growth performance,zinc content and expression of zinc transporters in young pigs

An experiment was conducted to compare the effects of zinc sulfate (ZS) and tribasic zinc sulfate (TBZ) as sources of supplemental zinc on growth performance, serum zinc (Zn) content and messenger RNA (mRNA) expression of Zn transporters (ZnT1/ZnT2/ZnT5/ZIP4/DMT1) of young growing pigs. A total of 96 Duroc × Landrace × Yorkshire pigs were randomly allotted to two treatments and were fed a basal diet supplemented with 100 mg/kg Zn from either ZS or TBZ for 28 days. Feed : gain ratio in pigs fed TBZ were lower (P < 0.05) than pigs fed ZS, and average daily weight gain tended to increase (0.05 ≤ P ≤ 0.10) in pigs fed TBZ. Compared with pigs fed ZS, pigs fed TBZ had a higher CuZn‐superoxide dismutase and Zn content in serum (P < 0.05) while they had a lower Zn content in feces (P < 0.05). In addition, ZIP4 mRNA expression of zinc transporter in either duodenum or jejunum of pigs fed TBZ were higher (P < 0.05) than pigs fed ZS. These results indicate that TBZ is more effective in serum Zn accumulation and intestinal Zn absorption, and might be a potential substitute for ZS in young growing pigs.     

Methodology for assessing zinc bioavailability: efficacy estimates for zinc-methionine, zinc sulfate, and zinc oxide.

The bioavailability of zinc-methionine (ZnMET) was compared to that of feed-grade ZnSO4.H2O using three different diets: purified (crystalline amino acid [AA]), semipurified (soy isolate), and complex (corn-soybean [C-SBM]) diet. With the Zn-deficient purified or semipurified diet, weight gain and tibia Zn responded linearly to both ZnSO4.H2O and ZnMET supplementation. Common-intercept, multiple linear regression indicated differences in Zn bioavailability between ZnMET and ZnSO4.H2O for both diets as indicated by bone Zn. With the ZnSO4.H2O standard set at 100%, bioavailability of Zn from ZnMET was 117% (P less than .05) in the AA diet and 177% (P less than .01) in the soy isolate diet. The ZnMET was also compared to ZnSO4.H2O in a C-SBM diet containing 117 mg of Zn/kg. When high levels of Zn were added to this diet (0, 250, 500, and 750 mg/kg of supplemental Zn), consistent tissue Zn responses did not occur beyond the first increment. Addition of lower levels of supplemental Zn (0, 5, 10, 20, 30, 40 and 50 mg/kg) to a Zn-unsupplemented C-SBM basal diet (45 mg/kg of Zn), however, resulted in a broken-line, two-slope response in tibia Zn for both ZnMET and ZnSO4.H2O. Inflection points occurred at 60 and 54 mg of Zn/kg of diet for ZnSO4.H2O and ZnMET, respectively. The ratio of slopes (ZnMET:ZnSO4.H2O) below the inflection points was 206% (P less than .01), indicating that Zn was considerably more bioavailable in ZnMET than in ZnSO4.H2O for chicks consuming C-SBM diets. When feed-grade ZnO was compared to feed-grade ZnSO4.H2O in chicks consuming C-SBM diets, bone Zn slopes below the respective inflection points indicated that Zn was 61% bioavailable in ZnO relative to ZnSO4.H2O.     

A specific appetite for zinc in zinc‐depleted domestic fowls

Zinc‐depleted chicks exhibited a significant preference in a two‐choice situation for a clearly discriminable diet containing 60 p.p.m. of zinc, rather than for a zinc‐deficient diet. The preference was well established by 24 h and continued for the duration of the experiment. Normal controls were initially indifferent to the high‐zinc diet, but after 6 d they too began preferentially to select the supplemented diet.