不同锌源对肉用仔鸡的饲养效果

主要研究以不同锌源对内仔鸡的生产性能和血液锌、胰脏锌,胫骨锌含量的影响,以验证固相合成蛋氨酸锌对肉用仔鸡的饲养效果.结果表明:相对于无机的硫酸锌,日粮中添加蛋氨酸锌能有效提高肉鸡的生产性能,提高胫骨中的锌含量;同时也表明液相合成蛋氨酸锌与固相合成蛋氨酸锌饲养效果相当.     

不同锌源对肉用仔鸡的饲养效果

主要研究以不同锌源对肉仔鸡的生产性能和血液锌，胰脏锌，胫骨锌含量的影响，以验证固相合成蛋氨酸锌对肉用仔鸡的饲养效果，结果表明，相对于无机的硫酸锌，日粮中添加蛋氨酸锌能有效提高肉鸡的生产性能，提高胫骨中的锌含量，同时也表明液相合成蛋氨酸锌与固相合成蛋氨酸锌饲养效果相当。     

低磷无维生素D_3的生长后期日粮对肉仔鸡生产性能及胫骨矿化的影响

设计两个试验，研究了生长后期日粮中钙、非植酸磷，维生素Ｄ３水平时肉鸡生产性能及胫骨矿化的影响。结果表明，日粮中钙、磷或维生素Ｄ３水平下降导致胫骨中灰分、钙和磷的含量降低（Ｐ＜０．０５）．但对胫骨中锰、锌含量无明显形响。生长后期日粮非植酸磷含量下降到０．１４％时钙下降到０．３７％或高到０．８５％不影响生长、饲料转化率、存活率及腿病发生率（Ｐ＞０．０５）：用石粉取代磷酸氢钙而使钙含量达０．９０％，钙／非植酸磷比值高达６．４３：１会显著抑制肉鸡生长，降低饲料转化率和胫骨矿化度（Ｐ＜０．０５），但对胫骨锰、锌含量无影响。     

静脉注射不同锌源与锌水平对肉仔鸡生长性能及组织锌含量的影响

用378只22日龄商品代AA肉公鸡进行静脉注射试验,研究不同锌源与锌水平对肉仔鸡生长性能及组织锌含量的影响。采用4种锌源（ZnSO₄·7H₂O、弱络合强度Zn-AA C、中等络合强度Zn-Pro B和偏极强络合强度Zn-Pro A）与3个日粮锌吸收率（0%、6％和12％）静脉注射锌水平构成的4×3两因子安排的完全随机设计,将22日龄肉公鸡按体重随机分成9个组(每组7个重复笼,每个重复笼6只鸡),分别翅静脉注射生理盐水（对照组）,或在生理盐水中溶解硫酸锌及弱、中等和偏极强络合强度有机锌源的注射液12 d。结果表明,锌源显著影响（P<0.10）注射后6 d胫骨灰锌含量,但对肉仔鸡注射后1～6 d和7～12 d的日采食量、日增重、料重比、第6 天胰脏锌及第12 天胰脏锌和胫骨灰锌均无显著影响（P>0.10）;锌水平显著影响（P<0.10）肉仔鸡注射后1～6 d的日增重和料重比、第6和12天的胰脏锌和胫骨灰锌,而对肉仔鸡注射后1～6 d日采食量和7～12 d的日采食量、日增重和料重比均无显著影响（P>0.10）;锌源与锌水平互作对肉仔鸡注射后以上各观测指标均无显著影响（P>0.10）。偏极强络合强度有机锌源组鸡胫骨灰锌含量显著低于弱络合强度有机锌源组和中等络合强度有机锌源组（P<0.10）,且有低于无机硫酸锌组的趋势（P>0.10）。对照组肉仔鸡的日增重显著低于注射锌吸收率6%组（P<0.10）,其料重比显著高于注射锌吸收率6%与12%组（P<0.10）,其它锌吸收率注射水平组之间鸡的日增与重料重比均无显著差异（P>0.10）;随着注射锌水平的升高,肉仔鸡注射后第6、12天胰脏和胫骨灰锌含量呈线性升高（P<0.10）。本试验结果表明,相对于胰脏锌和生长性能而言,静脉注射后第6天的胫骨灰锌能更敏感地反映出不同锌源对肉仔鸡生物学利用性的差异,而偏极强络合强度的有机锌最不利于肉仔鸡体组织的利用。     

含硫氨基酸与微量元素锰对肉鸡胫骨软骨症的影响

采用半纯合饲粮（Ｍｎ１．７ｍｇ／ｋｇ）研究过量含硫氨基酸（ＳＡＡ,为推荐量１１．４８ｇ／ｋｇ的１．５倍）与过量锰（Ｍｎ,为需要量６０ｍｇ／ｋｇ的２倍）对肉鸡胫骨软骨症（ＴＤ）的影响。试验将９６只１日龄ＡＡ肉雏鸡随机分为４组,即ＳＡＡ与Ｍｎ常量组（１１．４８ｇ／ｋｇ和６１．７ｍｇ／ｋｇ）,过量ＳＡＡ与常量Ｍｎ组（１７．１８ｇ／ｋｇ和１２１．７ｍｇ／ｋｇ）,常量ＳＡＡ与过量Ｍｎ组（１１．４８ｇ／ｋｇ和１２１．７ｍｇ／ｋｇ）和过量组（１７．１８ｇ／ｋｇ和１２１．７ｍｇ／ｋｇ）。试验２１ｄ的结果表明,过量ＳＡＡ抑制肉鸡生长、胫骨变长,诱导肉鸡ＴＤ的发病率升高;高锰日粮使肉鸡肝、肾、胰、血浆、心、肌肉组织中锰含量升高,诱导肉鸡ＴＤ的发病率上升;当日粮中过量ＳＡＡ和过量锰同时存在时,肉鸡生长的降低加剧,肝、肾、胰、血浆锰含量下降,胫骨长度增加,骨灰含量下降,诱导肉鸡ＴＤ的发病率更为严重。     

五种锌源对肉仔鸡生长性能、金属硫蛋白基因表达及组织锌含量的影响

为了探究同一添加水平的5种锌源对AA肉仔鸡生长性能、小肠金属硫蛋白(MT)mRNA及组织锌含量的影响,试验采用单因子随机设计,将240只1日龄AA肉仔鸡随机分成5组,选用玉米-豆粕型基础日粮(含锌22.68 mg/kg),在日粮中分别加入2种无机锌(ZnO、ZnSO4)和3种氨基酸螯合锌[赖氨酸锌(Lys-Zn)、蛋氨酸锌(Met-Zn)、甘氨酸锌(Gly-Zn),含锌量均为90 mg/kg],试验期为21 d,测定肉仔鸡生产性能、组织锌含量及MT mRNA相对表达量。结果表明:5种锌对肉鸡生长性能、肝脏和血液锌含量均无显著影响(P0.05)。Gly-Zn和Met-Zn组的胰脏、胫骨锌含量和小肠MT mRNA相对表达量显著高于2个无机锌组(P0.05);Lys-Zn组胰脏、胫骨锌含量和空肠MT mRNA相对表达量显著高于ZnO组(P0.05),与ZnSO4组无显著差异(P0.05),但有升高趋势。3种氨基酸螯合锌组中,Gly-Zn组和Met-Zn组胫骨锌含量、十二指肠MT mRNA相对表达量显著高于Lys-Zn组(P0.05);2种无机锌组中,ZnO组胰脏、胫骨锌含量显著低于ZnSO4组(P0.05)。说明Gly-Zn和Met-Zn能显著提高肉仔鸡小肠MT mRNA表达水平,增加组织锌含量。     

家禽对锌的生物利用率:文献回顾与分析

<正>锌是包括肉鸡在内的所有动物的必需微量元素。一旦缺锌,将造成生长性能下降和腿骨变形。在肉鸡饲料中添加锌元素以满足动物生长需求是十分必要的。可用的锌源很多,但他们不尽相同。不同锌源之间在理化特性,包括锌含量上都有所区别。近几十年来人们充分研究了额外补充锌对动物生产性能的影响,但对锌源的生物利用率评估方法的研究直到近几年才得到长足发展。由于在生产中需要缩小额外添加矿物质的安全范围,因此需要制定各种锌源所需效力的精确量化。     

日粮中锌含量和来源对肉鸡生产性能、氧化还原和免疫状态的影响

文章旨在在不影响肉鸡重要代谢功能、免疫状态和生长参数的前提下,探讨是否可以降低日粮中锌添加水平,评估纳米氧化锌是否可以达到上述目标。试验选择648只1日龄黄羽肉仔鸡,随机分为6组,每组6个重复,每个重复18只。试验日粮采用2×3因子设计,即2个锌来源(氧化锌和纳米氧化锌),3个锌水平(10、50和100 mg/kg)。结果显示:日粮锌源和锌水平均对肉鸡生长性能和存活率无显著影响(P 0.05)。锌源和锌水平对血清铜和铁含量的影响具有显著交互作用(P 0.05),其中100 mg/kg纳米氧化锌组血清铜含量最高(P 0.05),而铁含量较100 mg/kg氧化锌组显著降低(P 0.05)。纳米氧化锌替代氧化锌显著降低了血清白蛋白水平(P 0.05),增加了血清甘油三酯含量和谷丙转氨酶活力(P 0.05)。在肝脏抗氧化分析指标中,纳米氧化锌较氧化锌显著提高了CAT活力(P 0.05)。锌源和锌水平对血清IgA、IgM、IL-6水平的影响具有显著交互作用(P 0.05)。与相应剂量的氧化锌相比,纳米氧化锌添加水平达到100 mg/kg时IgM水平升高(P 0.05),中等剂量时IgM水平降低(P 0.05)。结论 :锌的添加剂量从100 mg/kg降低到10 mg/kg并不会影响肉鸡生长性能,但会通过增加血清甘油三酯水平对脂质代谢产生负面影响。用纳米氧化锌替代氧化锌对肉鸡生产性能、免疫状态均无显著影响,但在一定程度上提高了肉鸡抗氧化能力。     

饲粮钙磷水平对矮脚黄肉鸡生长性能及胫骨灰分含量的影响

试验旨在研究饲粮钙磷水平对矮脚黄肉鸡生长性能及胫骨灰分含量影响,得到矮脚黄肉鸡适宜的饲粮钙磷水平。综合肉鸡的生长性能及胫骨灰分含量的数据来看,矮脚黄肉鸡小鸡阶段饲粮的钙水平为0.90%,非植酸磷水平为0.40%,中鸡阶段饲粮钙水平为0.85%,非植酸磷水平为0.36%,大鸡阶段饲粮钙水平为0.80%,非植酸磷水平为0.33%可满足肉鸡生长及骨骼发育需要,在此基础上钙磷水平下调,肉鸡胫骨灰分含量显著降低(P0.01)。     

日粮不同阴阳离子对45日龄肉鸡胫骨软骨发育不良和某些生化指标的影响

采用３６０只１日龄Ａｖｉａｎ公雏,研究日粮中添加相同毫克当量（１６ｍｅｑ／ｋｇ）的阴阳离子对４５日龄肉仔鸡胫骨软骨发育不良（ＴＤ）和血液某些生化指标的影响。阳离子分别为钙（１．１７％）、钠（０．５３％）、钾（１．５１％）和镁（０．３５％）;阴离子分别为氯（０．８３％）,磷（０．７２％）和硫（０．５７％）。结果表明：高氯、磷、硫均不同程度地诱发４５日龄肉鸡ＴＤ的发生（Ｐ＜０．０５）,而添加阳离子将ＴＤ的发生率降至零。以诱发ＴＤ发生率的能力为指标,磷离子＞氯离子＞硫离子。氯、磷离子显著降低了红细胞血红蛋白浓度（ＭＣＨＣ,Ｐ＜０．０５）,损害了血氧运输效率。阴阳离子对４５日龄肉鸡的血液、胫骨发育其它指标均没有显著性影响（Ｐ＞０．０５）。４５日龄肉鸡的血液酸碱平衡、血红蛋白、胫骨发育及体增重均出现代偿性变化,ＴＤ发生率也有下降的趋势。这说明肉鸡在生长后期（２１～４５日龄）对酸碱平衡的适应或调节能力增强。     

Effects of organic forms of zinc on growth performance,tissue zinc distribution,and immune response of weanling pigs

This study was conducted to determine the effect of zinc level and source on growth performance, tissue Zn concentrations, intracellular distribution of Zn, and immune response in weanling pigs. Ninety-six 3-wk-old crossbred weanling pigs (BW = 6.45 +/- 0.17 kg) were assigned to one of six dietary treatments (four pigs per pen, four replicates per treatment) based on weight and litter origin. Treatments consisted of the following: 1) a corn-soybean meal-whey diet (1.2% lysine) with a basal level of 80 ppm of supplemental Zn from ZnSO4 (control; contained 104 ppm total Zn); 2) control + 80 ppm added Zn from ZnSO4; 3) control + 80 ppm added Zn from Zn methionine (ZnMet); 4) control + 80 ppm added Zn from Zn lysine (ZnLys); 5) control + 40 ppm added Zn from ZnMet and 40 ppm added Zn from ZnLys (ZnML); and 6) control + 160 ppm added Zn from ZnSO4. Zinc supplementation of the control diet had no effect on ADG or ADFI. Gain efficiency was less (P < 0.05) for pigs fed 80 ppm of Zn from ZnSO4 than for control pigs and pigs fed 160 ppm of Zn from ZnSO4. Organ weights, Zn concentration, and intracellular distribution of Zn in the liver, pancreas, and spleen were not affected (P = 0.12) by Zn level or source. Skin thickness response to phytohemagglutinin (PHA) was not affected (P = 0.53) by dietary treatment. Lymphocyte proliferation in response to PHA was greater (P < 0.05) in pigs fed ZnLys than in pigs fed the control diet or the ZnML diet; however, when pokeweed mitogen was used, lymphocyte proliferation was greatest (P < 0.05) in pigs fed the ZnMet diet than pigs fed the control, ZnLys, ZnML, or 160 ppm ZnSO4 diets. Antibody response to sheep red blood cells was not affected by dietary treatments. Supplementation of 80 ppm of Zn from ZnSO4 or ZnMet and 160 ppm of Zn from ZnSO4 decreased (P < 0.05) the antibody response to ovalbumin on d 7 compared with control pigs, but not on d 14. Phagocytic capability of peritoneal exudate cells was increased (P < 0.05) when 160 ppm of Zn from ZnSO4 was supplemented to the diet. The number of red blood cells ingested per phagocytic cell was increased (P < 0.05) in pigs fed the diet supplemented with a combination of ZnMet and ZnLys and the diet with 160 ppm of Zn from ZnSO4. Results suggest that the level of Zn recommended by NRC for weanling pigs was sufficient for optimal growth performance and immune responses, although macrophage function may be enhanced at greater levels of Zn. Source of Zn did not alter these measurements.     

Zinc bioavailability in feed-grade sources of zinc

Chick bioassays were used to assess bioavailability of zinc (Zn) from inorganic Zn sources. A soy isolate-dextrose diet containing 13 mg Zn/kg diet was supplemented with feed-grade sources of ZnSO4.H2O (ZnSO4) or ZnO and fed for 2 wk after a 7-d Zn-depletion protest period. Bioavailability of Zn in ZnO relative to ZnSO4 (set at 100%) was determined by multiple regression slope-ratio methodology, using both growth and tibia Zn accumulation in chicks fed graded levels of ZnO and ZnSO4. Linear responses for gain and tibia Zn occurred at dietary Zn levels (ZnSO4.7H2O) between 13 mg/kg (basal) and 33 mg/kg (gain) or 53 mg/kg (total tibia Zn). Therefore, two bioavailability assays were conducted using supplemental Zn levels of 0, 7.5 and 15 mg/kg from each Zn source. When weight gain was regressed on supplemental Zn intake, bioavailability of Zn in ZnO was only 61.2% (P less than .01) that of ZnSO4. When total tibia Zn was regressed on supplemental Zn intake, bioavailability of Zn compared with ZnSO4 (set at 100.0%) was 44.1% (P less than .001) for ZnO. With chicks fed soy-based diets, bioavailability of Zn from ZnO was less than that of ZnSO4.     

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.     

Zinc bioavailability in soybean meal

A phytate-containing soy protein concentrate (SPC) diet (13.5 mg Zn/kg) and a phytate-free egg white diet (.3 mg Zn/kg) were used to determine the relative bioavailability (RBV) of Zn in dehulled soybean meal (SBM) based on Zn depletion-repletion growth bioassays in young chicks. After a 4-d Zn depletion period, chick weight gain responded linearly (P < .01) to graded increments of supplemental Zn (0 to 10 mg/kg) from ZnSO4 x 7H2O, whether added to the Zn-deficient SPC or egg white diet. Slope, however, was over twice as great for the standard curve relating weight gain to supplemental Zn intake for the egg white diet as for the SPC diet. Addition of 7 to 10 mg Zn/kg from SBM to either Zn-deficient diet increased (P < .01) weight gain, but a similar SBM addition to either diet made adequate in Zn did not increase weight gain. Using standard-curve methodology, RBV of Zn in SBM was 78% when the the SPC diet was used, but it was only 40% when the egg white diet was used. The phytate contained in the SPC basal diet therefore markedly reduced the efficiency of utilizing the supplemental inorganic Zn from ZnSO4 x 7H2O. This lowered the slope of the standard curve so that, on a relative basis, the Zn in SBM had a higher RBV value than was the case for Zn utilization in SBM with the phytate-free egg white diet. The 78% Zn RBV value in SBM would seem to have the greatest relevance for practical-type corn-SBM diets.     

实用饲粮补锌对肉鸡组织锌、免疫器官及生产性能的影响

采用实用饲粮（玉米－多饼型,含锌３０ｍｇ／ｋｇ）,对狄高肉鸡（４～６周龄）分别补加锌４０和８０ｍｇ／ｋｇ,研究微量元素Ｚｎ对试鸡组织锌含量、免疫器官生长发育及生产性能的影响。结果表明饲粮缺锌（含Ｚｎ３０ｍｇ／ｋｇ）不影响鸡体重、饲料转化率和心、肝、肾、胰、肌胃、脑千克活体重（Ｐ＞０．０５）,但缺锌影响脾、胸腺、法氏囊、盲肠扁桃体、免疫器官及腺胃、小肠厚度、甲状腺生长发育（Ｐ＜０．０５或Ｐ＜０．０１）;饲粮补锌（４０、８０ｍｇ／ｋｇ）能改善免疫器官机能,增加胫骨、跗骨、趾骨、肝、胰、肾、心组织锌含量（Ｐ＜０．０５或Ｐ＜０．０１）;骨、肝、胰组织对饲粮锌缺乏较敏感,趾骨锌含量是标识鸡锌营养状况的灵敏指标。     

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.     

肉仔鸡饲粮中锌需要量的研究

取1日龄AA肉仔鸡600只,公、母各300只,随机分为10组,公、母各5组,每组4个重复,分别喂以含锌40mg/kg的基础日粮和含锌50、70、90和110mg/kg的添加锌日粮,以研究肉仔鸡对锌的需要量。试验期8周。结果表明,6周龄前日粮锌各水平对公、母鸡的体增重和饲料报酬无明显差异(P>0.05),40mg/kg锌可满足其生长需要。7周龄后,虽然公、母鸡分别在日粮含锌50和90mg/kg时可达到最大体增重,但差异不显著(P>0.05)。对于组织中的锌含量,不同组织、不同生长阶段对日粮补锌的反应不同。公、母鸡血液中锌含量并不随日粮锌含量的增加而升高;肾脏锌含量变化也不大;比较敏感的组织是胰和肝。组织锌含量依次为胰>肝>肾>血。血液中的碱性磷酸酶活性公、母鸡不同,但总的看来,随日龄增加而降低。铜锌超氧化物歧化酶(CuZnSOD)的活性不同组织、不同生长阶段和不同性别是不同的,母鸡比公鸡的酶活性高。根据各项指标的测定结果和经济效益综合分析,建议肉仔鸡对锌的需要量为40～50mg/kg。     

Effects of organic zinc and phytase supplementation in a maize-soybean meal diet on the performance and tissue zinc content of broiler chicks

1. The purpose of this study was to investigate the effects of Bioplex Zn (a chelated zinc proteinate) and phytase supplementation in a maize-soybean meal diet on the performance and tissue zinc (Zn) content of broiler chicks. Treatment structure consisted of a 2 x 6 factorial arrangement with two inclusions of phytase (0 or 500 PU/kg) and 6 of Bioplex Zn providing 0, 2, 4, 8, 16 and 32 mg Zn/kg diet. A total of 864 chicks were randomly assigned to each of 12 dietary treatments with 6 replicate cages of 12 chicks. 2. Dietary inclusion of phytase increased feed intake, weight gain, plasma Zn content, tibia Zn content, tibia and ash weight. 3. Dietary supplementation of Bioplex Zn linearly increased feed intake, weight gain, gain to feed ratio, plasma Zn concentration, liver Zn concentration, tibia Zn content, tibia and ash weight. 4. An interactive effect of phytase and Bioplex Zn on feed intake, weight gain, tibia Zn concentration and tibia ash weight was found. 5. One slope, straight broken-line analysis of weight gain regressed on the supplemental Zn level provided as Bioplex Zn indicated that 12 mg/kg supplemental Zn without phytase and 7.4 mg/kg supplemental Zn with phytase were required for the optimal weight gain of chicks.