硒摄入对肉牛组织中镉、铅、铜、铁、锌含量的影响

本研究旨在探讨硒元素摄入对动物体内必需微量元素铜、铁、锌和有害元素铅、镉含量的影响及其机理,为降低铅、镉在食物链中的迁移和积累的控制技术提供依据。试验选用20头杂交牛,随机分为2组,每组10头,对照组饲喂基础日粮,试验组在精饲料中以预混料的形式添加亚硒酸钠1.0 mg/kg。饲养试验期为150 d,饲养试验结束后,屠宰采集各组织样品测定铅、镉、铜、铁、锌含量。结果表明:添加亚硒酸钠后对肉牛日增重影响不显著(P>0.05),但能极显著降低肉牛心脏中铅、镉的含量和血液中铅的含量(P<0.01),极显著增加胃、肾脏、肝脏等组织中铅和镉含量(P<0.01);同时也增加铜、锌、铁在胃和铜、铁在肝脏中的蓄积(P<0.05)。结果提示,在饲料中添加微量元素硒,可以改变铅、镉、铜、锌、铁在动物体内各器官和组织中的分布水平,但不能有效降低肉牛各组织中铅、镉的蓄积。     

叶酸水平对断奶仔猪生长性能及血清组织中蛋白质代谢的指标影响

试验旨在研究日粮中添加不同剂量的叶酸对断奶仔猪生长性能及血清和组织中蛋白质代谢相关指标的影响。试验选择25日龄断奶仔猪160头(80头纯种大白和80头纯种长白,公、母各半),随机分为5个处理组,每个处理4个重复,每个重复8头猪,进行28 d的饲养试验。5种日粮分别在基础日粮上添加0、0.5、2.5、5 mg/kg和10 mg/kg叶酸。结果表明:添加2.5 mg/kg叶酸仔猪的全期日增重较基础日粮组有显著提高(P<0.05),提高了血清蛋白质浓度(P<0.05),降低了血清尿素氮浓度(P<0.01),并提高了肝脏DNA、RNA和蛋白质的含量(P<0.05)以及肌肉RNA/DNA和RNA/蛋白质值(P<0.05),而添加更高水平叶酸时却使仔猪生长性能下降。本试验结果显示,仔猪日粮中叶酸适宜添加量为2.5 mg/kg,叶酸不足或者过高都将影响动物的生长。     

镉对雌性生长猪血清性腺激素水平的影响

本试验以“杜长大”三元杂交猪为研究对象,研究了重金属镉对雌性生长猪血清性腺激素水平的影响。将48头体重27 kg左右的“杜长大”母猪按要求分成2组,每组3个重复,每个重复8头,分别饲喂不添加或添加10.0 mg/kg镉的饲粮。试验期83 d。饲养试验结束后,随机从各组的每个重复中选体重相近的猪各2头,共12头,进行屠宰。结果表明:添加10.0 mg/kg镉显著(P<0.05)降低猪的日增重18.6%、日采食量4.0%和饲料转化效率15.1%。使血清雌二醇,孕酮,卵泡刺激素,黄体生成素水平分别显著(P<0.05)降低了10.1%,36.7%,39.3%和16.6%。     

吡啶甲酸铬对吉富罗非鱼生长、饲料利用和非特异性免疫功能的影响

本试验研究饲料不同水平吡啶甲酸铬对其生长、饲料利用,体成分、血液生化指标和非特异性免疫功能的影响。600尾吉富罗非鱼分为5个处理组,每个处理各设4个重复,每重复30尾鱼。每个处理铬添加量分别为0、0.4、0.8、1.2 mg/kg和10.0 mg/kg,在0.38 m3玻璃纤维钢桶中用开放式流水养殖,饲养8周。结果表明,饲料中添加吡啶甲酸铬对吉富罗非鱼的增重率、特异生长率、饲料系数、蛋白效率及蛋白质沉积率均有显著影响(P<0.05)。当铬添加量为0～0.8 mg/kg时,随着添加量增加,可显著提高吉富罗非鱼增重率、特定生长率、蛋白质效率和蛋白质沉积率(P<0.05),显著降低饲料系数(P<0.05),但对成活率和肝体比无显著影响(P>0.05);当饲料中添加为1.2 mg/kg～10.0 mg/kg时并未能进一步提高罗非鱼的生长和饲料利用。同时,铬添加水平为0～0.8 mg/kg,随着添加水平增加,显著提高吉富罗非鱼全鱼的蛋白质和磷含量(P<0.05),显著降低全鱼水分、脂肪和灰分含量(P<0.05),并显著提高吉富罗非鱼血清总蛋白含量以及肝胰脏AKP、ACP和LZM的活性(P<0.05),显著降低血清葡萄糖含量(P<0.05),但对血清胆固醇和甘油三酯含量及肝胰脏T-SOD活性无显著影响(P>0.05)。当饲料中添加铬1.2 mg/kg和10.0 mg/kg,除了显著降低肝胰脏AKP活性外(P<0.05),对血清生化指标和肝胰脏非特异性免疫酶活性无显著影响(P>0.05)。综合生长、饲料利用、体组成成分、血液生化指标和肝胰脏非特异性免疫酶活性的影响结果表明,对于0.91～4.93 g吉富罗非鱼,饲料中以吡啶甲酸铬的形式添加0.8～1.2 mg/kg铬为宜。     

不同锌源对吉富罗非鱼生长性能、血清生化指标、血清和肝胰脏中微量元素含量的影响

本试验旨在研究饲料中添加不同锌源(肠溶型甘氨酸锌、甘氨酸锌、一水硫酸锌)对吉富罗非鱼生长性能、抗氧化能力、脂肪代谢以及血清和肝胰脏中抗氧化相关微量元素铜、铁、锰、锌含量的影响。将240尾初重为(47.54±0.84)g的吉富罗非鱼随机分为4组,每组3个重复,每个重复20尾。对照组罗非鱼饲喂基础饲料(锌含量为72.22 mg/kg),试验组罗非鱼分别饲喂在基础饲料中添加40 mg/kg(以锌计)肠溶型甘氨酸锌、甘氨酸锌、一水硫酸锌的试验饲料。试验期为40 d。结果显示:与对照组和一水硫酸锌组对比,饲料中添加肠溶型甘氨酸锌不仅可以显著提高吉富罗非鱼的增重率和蛋白质效率(P<0.05),还可以显著降低吉富罗非鱼肝体比和饲料系数(P<0.05)。与对照组和一水硫酸锌组相比,甘氨酸锌组饲料系数显著降低(P<0.05),蛋白质效率显著提高(P<0.05)。各组血清超氧化物歧化酶、碱性磷酸酶活性无显著差异(P>0.05),但肠溶型甘氨酸锌组、甘氨酸锌组血清丙二醛含量显著低于对照组(P<0.05)。肠溶型甘氨酸锌组血清总胆固醇含量显著高于其他各组(P<0.05),同时甘油三酯含量显著高于对照组和一水硫酸锌组(P<0.05)。各组血清中铜、铁、锰含量无显著差异(P>0.05),但肠溶型甘氨酸锌组血清和肝胰脏中锌含量显著高于对照组和一水硫酸锌组(P<0.05)。结果提示,饲料中添加肠溶型甘氨酸锌可提高吉富罗非鱼的生长性能,提高抗氧化能力,促进脂肪代谢,增加血清和肝胰脏中锌含量,且肠溶型甘氨酸锌的促生长效果优于甘氨酸锌。     

日粮不同锌水平对断奶仔猪血清及组织铜、锌沉积的影响

试验选用21日龄"杜×长×大"三元杂交的断奶仔猪40头,按体重和公、母各半原则随机分成Ⅰ、Ⅱ、Ⅲ和Ⅳ组,每组10头猪,分别在基础日粮中添加氧化锌,使试验Ⅰ~Ⅳ组中锌的含量分别达到100、1000、2000和3000 mg/kg,预试期7 d,正试期42 d。结果表明,3000 mg/kg锌日粮均能提高断奶仔猪血清锌水平(P<0.05),使血清锌含量显著上升(P<0.05),降低血清铜水平(P>0.05);3000 mg/kg锌日粮使肝脏、肾脏和十二指肠中锌含量极显著升高(P<0.01),各组间脾脏、淋巴结中锌含量差异均不显著(P>0.05),3000 mg/kg锌日粮会降低脾脏、淋巴结、十二指肠和肾脏中铜含量(P>0.05),提高肝脏中铜含量(P<0.01)。提示,3000 mg/kg锌日粮能增加断奶应激仔猪体内锌水平,降低部分组织中铜含量。     

降低铜、锌含量添加植酸酶对育肥猪生长性能、养分表观消化率及血清生化指标的影响

本试验旨在探讨植酸水平较高饲料中育肥猪适宜的铜、锌添加水平。试验选取108头55 kg左右的苏姜猪,采用2×3因子设计将试验猪随机分为6组,每组3个重复,每个重复6头。将低、中、高剂量铜、锌与植酸酶添加、不添加组合成6种饲料,每组饲喂其中1种饲料。试验期42 d,测定试验期间育肥猪生长性能、养分表观消化率、血清生化指标及血清和掌骨铜、锌含量。结果显示,降低饲料中铜、锌含量并添加植酸酶未显著影响育肥猪生长性能（P>0.05）。将铜、锌水平从高剂量降低到中、低剂量极显著地提高了铜、锌的表观消化率（P<0.01）,极显著降低了血清铜含量（P<0.01）;从高剂量降低到中剂量极显著降低了血清碱性磷酸酶活性（P<0.01）。添加植酸酶极显著提高了粗蛋白质表观消化率（P<0.01）,显著提高了锌表观消化率和血清碱性磷酸酶活性（P<0.05）。铜、锌水平和添加植酸酶对血清和掌骨锌含量、血清铜蓝蛋白和乳酸脱氢酶活力均无显著影响（P>0.05）。综上所述,在较高植酸水平的饲料中将铜、锌含量降到中等水平可提高铜、锌表观消化率,而不影响生长性能。添加植酸酶有利于提高粗蛋白质、锌的表观消化率。因而建议育肥苏姜猪饲料中添加中剂量铜、锌（即25 mg/kg铜＋40 mg/kg锌）并添加植酸酶。     

日本沼虾幼虾对饲料中锌的需求量

本试验通过研究饲料中锌含量对日本沼虾幼虾生长性能、体组成以及组织中锌、铜、铁含量的影响,以确定日本沼虾幼虾对饲料中锌的需求量。以七水硫酸锌为锌源,配制锌含量分别为7.11、17.25、26.15、36.89、55.14、73.98mg/kg的6种试验饲料。选取初体重为(0.12±0.01)g的日本沼虾幼虾900尾,随机分成6组(每组3个重复,每个重复50尾),每组投喂1种试验饲料。试验期为50d。结果表明:饲料中锌含量从7.11mg/kg增加到36.89mg/kg时增重率显著上升(P<0.05),而由36.89mg/kg增加到73.98mg/kg时则无显著变化(P>0.05)。饲料系数以36.89mg/kg组最低,显著低于7.11和17.25mg/kg组(P<0.05)。饲料锌含量对日本沼虾幼虾的成活率,全虾粗蛋白质、粗脂肪、粗灰分以及肌肉锌、铜含量无显著影响(P>0.05)。随着饲料中锌含量的增加,全虾和甲壳锌含量呈先上升后平稳的趋势,肝胰脏锌含量呈上升趋势。饲料中锌含量对全虾、肌肉、甲壳和肝胰脏铁含量以及全虾、甲壳和肝胰脏铜含量均有显著影响(P<0.05)。在本试验条件下,饲料中的锌含量不仅影响日本沼虾幼虾的生长性能,而且影响全虾及组织中锌、铜、铁的含量。通过折线模型分析得出,日本沼虾幼虾获得最大生长和甲壳锌沉积量的饲料锌需求量分别为31.90和58.62mg/kg。     

Dietary Supplementation with Copper, Iron and Zinc Affects Contents of Lead and Cadmium in Tissues and Blood of Beef Cattles

本研究旨在探讨饲粮添加必需微量元素铜、铁和锌对肉牛组织和血液铅和镉含量的影响.选用20头12月龄肉牛,随机分为2组,每组10头,各组分别饲喂基础精饲料(对照组)和基础精饲料中添加铜20 mg、铁200 mg和锌200 mg的试验精饲料(试验组),粗饲料自由采食.试验期为150 d.每天以组为单位计算牛的采食量；每30 d称取牛体重并采集血液样品,试验结束后,屠宰试验牛,采集肾脏、肝脏、心脏、胰脏、脾脏、瘤胃、大肠及背肌组织样品,测定血液和组织中铅和镉含量.结果表明:牛精饲料中添加铁、铜和锌后,平均日增重极显著地提高了12.50％(P＜0.01),料重比极显著地降低了15.68％ (P ＜0.01)；铅含量在胰脏和瘤胃中极显著增加(P＜0.01),在脾脏和血液中显著减少(P＜0.05),在其余组织中无显著变化(P＞0.05),铅蓄积的器官主要是胃；镉含量在肾脏、肝脏、脾脏、瘤胃和大肠中均极显著增加(P＜0.01),但心脏中的镉含量极显著降低(P＜0.01),镉蓄积的器官主要是肾脏.结果提示,在饲粮中添加铜、铁和锌可以改善肉牛的生长性能,但不能有效减少脏器及肌肉组织中铅和镉的蓄积.     

稻米来源镉对生长育肥猪组织重金属沉积规律的影响

镉可通过肠道内二价金属离子转运蛋白1(DMT1)的介导进入动物机体,并与机体内其他二价金属元素(如铁、锌、铜等)的吸收转运存在相互作用。本试验旨在探究稻米来源镉对生长育肥猪组织重金属沉积规律的影响,为寻求降低镉在机体内残留的措施提供参考。选用初始体重为(31.57±2.82)kg的健康生长猪28头,随机分为体重没有明显差异的两组,即对照组(Cd,0.15 mg/kg)与试验组(Cd,0.55 mg/kg),每组14头;饲喂期结束时,生长阶段取6头,生长肥育阶段取8头,分别屠宰;现场测定屠宰性能、器官指数,取各组织样品测定二价重金属的沉积量。结果显示,试验组与对照组相比,无论生长和生长育肥阶段,屠宰性能和器官指数均无显著差异。重金属沉积方面:生长阶段,肝脏中锌含量显著降低,铁含量显著增高,铜含量显著降低;肾脏中锌含量显著降低,铁含量无显著差异,铜含量显著降低。生长育肥阶段,肝脏中锌含量显著增高,铁含量显著降低,铜含量无显著差异;肾脏中锌含量显著增高,铁含量显著降低,铜含量显著增高。其余组织中其他二价金属元素的沉积量并无显著变化。由此表明,较低剂量的稻米来源镉主要影响铁、锌、铜在肝脏及肾脏的分布规律。     

Effects of cadmium on serum sex hormone levels in pigs

An inhibition of sex hormone secretion is observed in domestic animals exposed to cadmium in experimental conditions. Ninety-six gilts (Duroc x Landrace x Yorkshire, initial weight 27.59 kg) were randomly assigned into four different groups with three replications in each group (eight gilts per replication). The groups received the corn-soybean basal diet and supplemented with 0, 0.5, 5.0 and 10.0 mg/kg cadmium (as CdCl2) respectively. The feeding trial was ended when body weight of pigs was approximately 90 kg. The results showed that 10.0 mg/kg cadmium significantly decreased average daily gain (p < 0.05) and increased feed/gain ratio (p < 0.05) of pigs. Follicle-stimulating hormone, luteinizing hormone, oestradiol (E2) and progesterone levels in serum of the pigs fed the diet supplemented with 10.0 mg/kg cadmium were lower significantly than those of the control (p < 0.05). Compared with the control, no changes were found in the levels mentioned above when the pigs fed the diet supplemented with 0.5 or 5.0 mg/kg cadmium (p > 0.05). The changes of regulatory mechanism of the pituitary-ovary axis may be the result of cadmium accumulation in pituitary and ovary and should be investigated further.     

Chemical study of body organs in papular dermatitis in fattened pigs

In twenty fattened pigs with papular dermatitis (PD) and in seventeen pigs with no skin lesions (K),--the pigs had the live weight from 95 to 105 kg and came from a D. large fattening house situated in a region with extensive mining (lignite extraction)--we analyzed the skin, muscle, kidneys and liver for the contents of chemical elements (zinc, copper, manganese, lead, cadmium, mercury, chromium) and aflatoxin B1. In pancreas we analyzed only the content of aflatoxin B1. In comparison with the K group, the pigs with PD had in the skin the higher contents of zinc (PD 15.7 +/- 7.1 mg per kg, K 10.1 +/- 1.3 mg per kg, P less than 0.05) and aflatoxin B1 (PD 3.18 +/- 1.53 micrograms per kg, K 1.56 +/- 0.49 microgram per kg, P less than 0.05); in the muscle the higher contents of zinc (PD 30.2 +/- 7.6 mg per kg, K 23.8 +/- 5.4 mg per kg, P less than 0.05), of lead (PD 0.48 +/- 0.31 mg per kg, K 0.25 +/- 0.28 mg per kg, P less than 0.05) and copper (PD 3.19 +/- 3.11 mg per kg, K 0.98 +/- 0.41 mg per kg, P less than 0.01); in the kidneys the higher contents of lead (PD 0.96 +/- 0.75 mg per kg, K 0.26 +/- 0.34 mg per kg, P less than 0.01), cadmium (PD 0.38 +/- 0.14 mg per kg, K 0.26 +/- 0.20 mg per kg, P less than 0.05), manganese (PD 1.14 +/- 0.04 mg per kg, K 0.94 +/- 0.42 mg per kg, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

有机铬对肉鸡日粮、粪中微量元素和小肠组织结构的影响

试验选用1日龄爱拔益加(AA)肉鸡792只,设6个处理,每个处理4个重复,每个重复33只鸡。对照组饲喂玉米-豆粕型基础日粮,试验组分别饲喂在基础日粮中添加酵母铬0.2 mg/kg、吡啶甲酸铬0.2 mg/kg和蛋氨酸铬0.1 mg/kg(Ⅰ)、0.2 mg/kg(Ⅱ)、0.6 mg/kg(Ⅲ)的日粮(以Cr3+计),自由采食、饮水,试验期为49 d。旨在研究日粮中添加不同有机铬源对肉鸡日粮、粪中微量元素和小肠组织结构的影响。结果表明,(1)酵母铬组和吡啶甲酸铬组日粮铜水平均显著降低(P<0.05),蛋氨酸铬(Ⅱ)组日粮锌水平显著降低(P<0.05);吡啶甲酸铬组和蛋氨酸铬(Ⅱ)组粪铜、粪锌排泄量均显著提高(P<0.05),且蛋氨酸铬(Ⅱ)组粪锰水平显著增加(P<0.05);不同铬源对日粮铁水平和粪铁排泄量均未产生显著影响(P>0.05)。(2)不同铬源均增加空肠黏膜厚度的趋势,且蛋氨酸铬(Ⅲ)组较对照组显著提高28.57%(P<0.05);不同铬源均能降低回肠绒毛长度和黏膜厚度,除酵母铬组黏膜厚度外,其他各试验组均达到显著水平(P<0.05);各试验组十二指肠绒毛长度和黏膜厚度差异均不显著(P>0.05)。由此可见,铬对日粮和粪中铜、锌、锰水平影响显著,对铁影响不显著;能增加空肠黏膜厚度,显著降低回肠绒毛长度和黏膜厚度。     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance, digestive enzymes, tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs. One hundred crossbred pigs weaned at 28 ± 2 d of age were assigned randomly to one of the following diets with 5 replicates: corn-soybean basal diet with 10, 100, 175, 250 mg/kg of Cu as CuSO₄•5H₂O. The results showed that 250 mg/kg Cu had a positive effect (P < 0.05) on average daily gain, daily feed intake and ratio of gain/feed. Compared to 10 mg/kg Cu, higher Cu had significant effect on the apparent digestibility of protein and fat (P < 0.05). The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P < 0.05) and had no effect on intestinal morphology. The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu, no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg). Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation. There was no positive effect (P > 0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa. However, higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa. These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance, nutrient digestibility and intestinal enzyme activities of weanling pigs.     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance,digestive enzymes,tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs.One hundred crossbred pigs weaned at 28±2 d of age were assigned randomly to one of the following diets with 5 replicates:corn-soybean basal diet with 10,100,175,250 mg/kg of Cu as CuSO4·5H2O.The results showed that 250 mg/kg Cu had a positive effect (P0.05) on average daily gain,daily feed intake and ratio of gain/feed.Compared to 10 mg/kg Cu,higher Cu had significant effect on the apparent digestibility of protein and fat (P0.05).The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P0.05) and had no effect on intestinal morphology.The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu,no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg).Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation.There was no positive effect (P0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa.However,higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa.These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance,nutrient digestibility and intestinal enzyme activities of weanling pigs.     

Effect of Cadmium in Feed on Organs and Meat Colour of Growing Pigs

One hundred and ninety-two barrows (Duroc × Landrace × Yorkshire, initial weight 27.7 kg) were used to investigate the effects of cadmium in feed on the function of selected organs and meat colour of growing pigs. The pigs were randomly allocatted into four different treatments. Each treatment included three replications with 16 pigs per replicate. The animals were fed corn–soybean basal diet and supplemented with 0, 0.5, 5.0, 10.0 mg/kg cadmium (as CdCl₂), respectively. The feeding trial ended when the average body weight of the pigs reach 90 kg. The results showed that, compared with controls, addition of 10 mg/kg cadmium to the diet resulted in significant elevations of relative weight of liver and spleen by 18.3% (p < 0.05) and 19.7% (p < 0.05) respectively, and of serum glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) activities by 17.8% (p < 0.05) and 27.4% (p < 0.05) respectively; and significant decreases of Na⁺/K⁺-ATPase activity in the liver by 24.6% (p < 0.05), the redness of longissimus dorsi by 26.6% (p < 0.05) and 24.9% (p < 0.05) at 0.75 h and 16 h post mortem, respectively, and of the myoglobin content of longissimus dorsi by 19.4% (p < 0.05). No changes were found in these indices above when the pigs were fed the diet supplied with 0.5 or 5 mg/kg cadmium (p > 0.05), nor in renal functions among cadmium-treatment treatments (p > 0.05) as indicated is the activities of urinary N-acetyl-β-d-glucosaminidase (NAG) and alkaline phosphatase (ALP) and the content of urinary protein. The study indicated the adverse effects of 10 mg/kg cadmium in feed on liver functions and meat colour of growing pigs.     

不同锌源及添加水平对肉仔鸡生长性能的影响及其生物学利用率评价

本试验旨在研究碱式氯化锌(BZC)和蛋白锌(PRZ)相对于一水合硫酸锌(ZSM)的生物学利用率以及对肉仔鸡生长性能的影响。采用双因素(3×3+1)完全随机试验设计,选取720只1日龄健康雄性爱拔益加(AA)肉仔鸡,随机分为10个组,每组6个重复,每个重复12只鸡。对照组饲喂玉米-豆粕型基础饲粮,3个ZSM组分别饲喂在基础饲粮基础上添加20、40和80 mg/kg ZSM的饲粮,3个BZC组分别饲喂在基础饲粮基础上添加20、40和80 mg/kg BZC的饲粮,3个PRZ组分别饲喂在基础饲粮基础上添加20、40和80 mg/kg PRZ的饲粮。各组不同锌源添加量均以锌计。试验期42 d,分为1~14日龄、15~28日龄和29~42日龄3个阶段。分别在14和28日龄时,从各重复中选取1只接近平均体重的鸡进行屠宰,测定血浆锌含量和抗氧化指标、组织锌含量以及胰脏锌相关蛋白基因表达水平。结果表明:1)1~14日龄,与对照组相比,饲粮添加不同锌源和添加不同水平锌显著提高肉仔鸡平均日增重(ADG)和14日龄体重(P<0.05),显著降低料重比(F/G)(P<0.05),且以添加40 mg/kg BZC效果最佳;在不同锌源之间,BZC组ADG显著高于ZSM组和PRZ组(P<0.05),F/G显著低于ZSM组(P<0.05)。2)随着饲粮锌添加水平的提高,肉仔鸡14日龄血浆锌含量和14和28日龄胫骨锌含量显著提高(P<0.05);14日龄,BZC组血浆碱性磷酸酶(ALP)活性显著高于ZSM组(P<0.05),PRZ组血浆总超氧化物歧化酶(T-SOD)和铜锌超氧化物歧化酶(CuZn-SOD)活性显著高于ZSM组和BZC组(P<0.05)。3)与对照组相比,饲粮添加不同锌源和添加不同水平锌显著提高14日龄肉仔鸡胰脏金属硫蛋白(MT)mRNA表达量(P<0.05);且PRZ组14日龄胰脏MT mRNA表达量显著高于ZSM组和BZC组(P<0.05),PRZ组28日龄胰脏MT mRNA表达量显著高于ZSM组(P<0.05)。4)采用斜率比法,以ZSM生物学利用率为参照标准(100.00%),选择1~14日龄ADG、F/G和14日龄血浆ALP活性作为评价指标,BZC的相对生物学利用率分别为110.82%、113.55%和113.26%,PRZ的相对生物学利用率为102.90%、113.38%和109.64%;而以血浆T-SOD、CuZn-SOD活性和胰脏MT mRNA表达量作为评价指标,BZC的相对生物学利用率分别为98.90%、 111.58%和107.87%, PRZ的相对生物学利用率分别为113.86%、 96.56%和130.56%。综上所述,BZC对提高肉仔鸡生长性能的效果和相对生物学利用率优于ZSM,甚至达到RPZ的效果。     

The effects of withdrawal of vitamin and trace mineral supplements from layer diets on egg yield and trace mineral composition

1. This study was conducted as three trials. 2. In the first trial, zinc, manganese, copper and iron concentrations were determined in dietary raw materials collected from various regions of Turkey. 3. In the second trial, 200 Hisex Brown laying hens, 30 weeks of age, were divided into two groups. The first group served as controls and were fed on a standard commercial layer diet. The second group were fed on a commercial layer diet that was not supplemented with trace minerals and vitamins. Egg production, egg weight, specific gravity, food consumption and food efficiency of the birds in each group were determined. In the unsupplemented group, egg production (0.75 vs 0.83) and food intake (114 vs 122 g) were lower than the those of the control group (P < 0.05). Food efficiency was 2.42 (kg food/kg gain) in the group consuming the unsupplemented diet and 2.36 in the controls. 4. In the third trial, as in Trial 2, Hisex Brown laying hens, 62 weeks of age were used. In the unsupplemented group, the mean egg weight was significantly lower than that of controls (68.0 vs 69.6 g) (P < 0.01). 5. At the end of the second and third trials, egg samples collected from experimental groups were hard boiled in water. The levels of zinc, manganese, copper and iron in the egg yolk were determined. The zinc level of the egg yolk from the control group of second trial was higher (23.5 mg/kg) than those of the unsupplemented group (13.6 mg/kg).     

高效包被氧化锌对断奶仔猪生长性能、血液生化指标及微量元素排泄量的影响

[目的]研究高效包被氧化锌对断奶仔猪生长性能、血液生化指标及微量元素（铜、铁、锌、锰）排泄量的影响。[方法]试验选取60头28日龄平均体重为（7.26±0.46）kg的杜×长×大三元杂交断奶仔猪,随机分为3组,每组设10个重复,每个重复2头仔猪。普通氧化锌组饲喂基础日粮+普通氧化锌1 966 mg/kg,锌元素含量1 500 mg/kg;高效包被氧化锌组饲喂基础日粮+高效包被氧化锌1 000 mg/kg,锌元素含量500 mg/kg;基础日粮组饲喂不添加氧化锌的基础日粮。试验期为35 d,预试期7 d,正试期28 d。试验结束后计算仔猪平均日采食量、平均日增重、料重比、腹泻率;测定全血血红蛋白含量、铜锌—超氧化物歧化酶活力以及血液中铜、铁、锌元素含量;计算皮毛指数;测定粪便中铜、铁、锌、锰元素含量。[结果]与基础日粮组相比,普通氧化锌组和高效包被氧化锌组的平均日采食量和平均日增重均显著（P<0.05）提高,料重比和腹泻率显著（P<0.05）降低;高效包被氧化锌组的平均日采食量、平均日增重、料重比和腹泻率与普通氧化锌组相比差异不显著（P>0.05）。全血血红蛋白含量3组差异不显著（P>0.05）;高效包被氧化锌组铜锌—超氧化物歧化酶活力显著（P<0.05）高于基础日粮组和普通氧化锌组;血液中铜、铁元素含量3组差异不显著（P>0.05）;普通氧化锌组血液中锌元素含量显著（P<0.05）高于基础日粮组和高效包被氧化锌组。高效包被氧化锌组皮毛指数优于普通氧化锌组。高效包被氧化锌组粪便中的锌元素含量极显著（P<0.01）低于普通氧化锌组;各组粪便中的铜、铁、锰元素含量差异不显著（P>0.05）。[结论]日粮中添加锌元素含量为500 mg/kg的高效包被氧化锌能够降低断奶仔猪腹泻率,提高仔猪生长性能、皮毛指数和机体抗氧化能力,降低粪便中锌排放量,减少环境污染。