【作者】 苏振刚；

【导师】 陈代文；

【作者基本信息】 四川农业大学 ， 动物营养与饲料科学， 2004， 硕士

【摘要】 采用斜率比法，以七水硫酸锌为参照物，通过研究添加不同水平的Zn-AA对肉鸡生产性能、组织锌残留量和免疫功能的影响，评定Zn-AA的相对生物学效价，确定Zn-AA适宜的添加量。试验采用2×5因子试验设计，以玉米-豆粕型日粮作基础日粮(对照组)，分别添加20、50、100、150mg／kg的锌(来自无机锌)和20、50、100、150mg／kg的锌(来自Zn-AA)构成8种试验日粮。试验共9个处理，每个处理5个重复，每个重复20只鸡。试验用1日龄商品代艾维茵肉鸡900只。试验期7周，试验鸡自由采食和饮水。分别于3周和7周时，计算日增重(ADG)、日采食量(ADFI)和饲料转化效率(F／G)；同时每个重复随机选择一只鸡采血，用于测血清锌含量和测淋巴细胞记数和淋巴细胞转化率；采血后屠宰，取胸腺、脾脏、和法氏囊称重计算免疫器官指数；同时采集腿部肌肉、肝脏和皮肤样品检测锌含量。 试验结果为：① 对0-7周龄的肉鸡，各无机锌和Zn-AA处理组都有提高生产性能趋势。与对照组相比，ADG分别提高了5.93-13.07％和10.66-13.84％(P＞0.05)，ADFI分别提高了5.02-12.74％和10.44-12.81％(P＞0.05)。在0-3周，在肉鸡日粮中添加锌有降低ADFI的趋势，与对照相比，各无机锌和Zn-AA处理组ADFI分别下降了3.72％、5.12％、1.24％、0.88％(P＞0.05)和1.71％、2.06％、1.24％、0.72％(P＞0.05)。② 在本试验条件下，与对照组相比，随日粮锌水平的增加，肉鸡血清、肝脏、肌肉和皮肤锌浓度都增加。③ 在本研究中，随着锌添加水平的提高，0-3周龄试验鸡Ea、Et和淋巴细胞转化率都显著或极显著提高，而对免疫器官指数的影响差异不显著(P＞0.05)。④ 在本试验条件下，以ADG和ADFI为评定指标，在0-3周时Zn-AA的最适添加量分别为64.5mg／kg、103mg／kg，无机锌的最适添加量分别为111.11mg／kg、65.83mg／kg；在4-7周时Zn-AA的最适添加量分别为107.94mg／kg、100.43mg／kg，无机锌的最适添加量分别为175 mg／kg、192.63mg／kg：0-7周Zn-AA的最适添加量分别为93.43mg／kg、92.64mg／kg，无机锌的最适添加量分别123.5 mg／kg、129.75mg／kg。⑤ 在本试验中，采用斜率比法，以七水硫酸锌为标准物，(生物学效价为100％)，以日增重、血清锌含量和肝脏锌含量为评定指标，Zn-AA的相对生物学效价0-3周分别为101.72％、144.67％和125.97％，0-7周分别为151.82％、192.42％和四川农业大学硕卜学位论文106.82%。 结果表明:①本研究中，随着锌添加水平提高，肉鸡的生产性能有增高的趋势。添加氨基酸鳌合锌和添加无机锌没有显著的差异。②在本试验条件下，以血清锌含量和肝脏锌含量为评定指标，Zn一AA生物学效价要高于无机锌。③要获得相同的生产性能，Zn一AA的添加量要低于无机锌。④锌可以提高动物机体免疫功能。更多还原

【Abstract】 In the experiment,using the slope-ratio technique , the experiment was conducted with 900 one-day old broilers to estimate bioavailability of zinc-amino acid chelate (Zn-AA). 2X5 factorial design was used in the experiment.Broilers were allotted randomly to 9 dietary treatments with 5 duplicates that included a basic diet (control group) and 8 tested diets which were formed by supplemental with different levels (20,50,100 and l50mg/kg) of inorganic Zinc and Zn-AA respectively. The trail tasted 7 weeks and the chicks were allowed ad libitum access to feed and water. ADG , ADFI and F/G were recorded during 0-3 weeks and 4-7 weeks.At 3rd and 7th weeks,one broiler was chosen randomly from each replicate,and blood samples were pooled by replicate.Serum was then prepared by centrifugation.Lymphocyte number and lymphocyte proliferative response were measured.Chicks were killed and thymus,spleen and bursa of Fabricius were removed to weight to calculate the ration of organ weight to body weight.At the same time.samples of muscle.liver and skin were collected to measure Zinc concentration.The results indicated that: (1) Supplementation with inorganic Zinc and Zn-AA had the tendence to improve the growth performance of 0-7-week old broiler.Compared to the control group,ADG were increased by 5.93-13.07% and 10.66-13.84% respectively,ADFI were increased by 5.02-12.74% and 10.44-12.81%.At 0-3 week period, compared to the control group,ADFl were decreased by 3.72%,5.12%, 1.24%,0.88% and 1.71%,2.06%.1.24%,0.72% respectively for inorganic Zinc and Zn-AA treatment (P>0.05) .(2) Under the condition of this experiment,compared to the control group,with the increasing dietary Zn level.Zn content in determined tissues and organs.serum Zn increased .(3) Under the condition of this experiment,with the increasing dietary Zn level.Ea.Et and lymphocyteproliferative Response of the broilers increased signincantly(p<0.05 or p<0.01),but immunity organs’ exponent wasn’t affected by the Zn supplementation (P>0.05) (4) Under the condition of the experiment, using means of ADG and ADFI as evaluated index,at 0-3 week-stage.the optima supplemental levels of Zn-AA were 64.5 mg/kg, 103 mg/kg and those of inorganic Zn were 111.11mg/kg .65.83 mg/kg respectively. At 4-7 week-stage.the optima supplement of Zn-AA were 107.94 mg/kg,100.43 mg/kg and the optima supplement inorganic Zn 175mg/kg ,192.63 mg/kg respectively. At 0-7 week-stage.the optima supplement of Zn-AA were 93.43 mg/kg,92.64 mg/kg and the optima supplement inorganic Zn 123.5mg/kg ,129.75 mg/kg respectively.?In the experiment.using the slope-ratio technique ,ADG and Zn content of serum and liver were sensitive indicator.lf Zn from ZnSO4 7H2O set at 100%,the relative bioavailability were estimated to be 101.72%, 144.67% and 125.97% during 0-3 week-period and 151.82%. 192.42% and 106.82% during 0-3 week-period.The experiment showed that the performance of the broilers was improved with zinc supplementation,the bioavailability of zinc aniino acid chelate estimated by ADG, zinc contents in serum and liver was higher than that of inorganic zinc .Zinc supplementation can improve immunity function.更多还原