【作者】 戴洪伟；

【导师】 姚军虎；

【作者基本信息】 西北农林科技大学 ， 动物营养与饲料科学， 2003， 硕士

【摘要】 本试验设五个处理，每个处理三个重复，每重复20只艾维茵肉仔鸡，公母各半，共计300只。各处理的蛋氨酸水平分别为0.26%、0.31%、0.36%、0.41%和0.46%，观测日粮蛋氨酸含量对21~42日龄各阶段体重、日采食量、料肉比、胸肌率、腿肌率、腹脂率、血浆尿酸浓度等指标的影响，并采用折线模型和二次多项式函数模型估计21~42日龄肉仔鸡蛋氨酸需要量。试验结果表明：1．不同蛋氨酸水平对肉仔鸡生产性能的影响42日龄体重与日粮蛋氨酸水平间呈显著的二次曲线关系，其中日粮蛋氨酸含量为0.31%、0.36%、0.41%和0.46%时42日龄体重差异不显著(p>0.05)，但均显著高于日粮蛋氨酸0.26%时的42日龄体重。平均日采食量与日粮蛋氨酸含量之间没有显著的相关关系。料肉比与日粮蛋氨酸的含量间呈显著的二次曲线关系，其中0.36%、0.41%和0.46%蛋氨酸组间、0.26%和0.31%蛋氨酸组间差异不显著(p>0.05)， 0.26%水平与0.36%、0.41%、0.46%蛋氨酸间差异显著(p<0.05)。2．不同蛋氨酸水平对肉仔鸡屠宰性能的影响胸肌率与日粮蛋氨酸含量间呈显著的二次曲线关系，其中0.26%蛋氨酸组显著(p<0.05)低于其余各组。腿肌率与日粮蛋氨酸含量间没有显著的相关关系。腹脂率与日粮蛋氨酸含量间呈显著的二次曲线关系，其中0.26%、0.31%蛋氨酸水平间差异不显著(p>0.05)，显著大于0.36%、0.41%、0.46%蛋氨酸组(p<0.05),后三组间差异不显著。3．不同蛋氨酸水平对血浆尿酸浓度的影响血浆尿酸浓度与日粮蛋氨酸含量有显著的二次曲线关系，总的变化趋势是随饲粮蛋氨酸水平的增加，血浆尿酸水平呈先降低后升高的趋势。其中0.36%和0.41%蛋氨酸组血浆尿酸浓度较低(p>0.05),高或低日粮蛋氨酸均趋于增加血浆尿酸浓度(p>0.05)。4．拟合的数学模型对肉仔鸡需要量估计的影响 <WP=5>以42日龄体重、料肉比、胸肉率、腹脂率和血浆尿酸浓度为衡量指标，采用折线法估计的21～42日龄肉仔鸡蛋氨酸需要量分别为0.358%、0.359%、0.338%、0.415%、0.356%。采用二次多项式函数模型估计的蛋氨酸需要量分别为0.392%、0.400%、0.390%、0.432%、0.372%。二次多项式函数模型得出的蛋氨酸需要量高于折线模型估计的需要量。更多还原

【Abstract】 The experiment was conducted on different criteria measured and manthematical models used .Three hundred 21-day old Avian broiler chiks were randomly allocated into five different groups consisted of 3 replication 20 birds each with equal number of males and females. Supplemental dietary Met levels were 0.26%, 0.31%, 0.36%, 41%, 0.46%.Met affected on indices measure was observed. Including body weight, feed intake ,feed conversion rate , breast muscle weight,leg muscle weight ,abdominal fat and the uric acid concentration in plasma.And calculation breast muscle rate , leg muscle rate,abdominal fat rate .The broken-linear model and quadratic multinomial model was used to estimate methionine(Met) requirement of 21-42 days broiler . The results of this experiment were as follow: 1. Effect of different Met levels on the growth performance of 21 -42 days broilerBody weight at 42 days showed out quadratic related with Met levels. Body weight was no significantly difference among 0.31%, 0.36%, 0.41%and 0.46%Met, but was significantly higher than that of 0.26%Met. Feed intake did not show out quadratic related with Met levels. Feed/meat ratio showed out quadratic related with Met levels.There were not significantly difference between 0.36%,0.41%and 0.46%Met, but had significantly with Q.26%,0.31% Met.0.26%Met had no significantly difference between 0.36%, 0.41%and 0.46%Met. 2. Effect of different Met levels on the slaguant performance of 21 -42 days broiler <WP=7>Abdominal meal rate showed out quadratic related with Met levels.Fed a diet containing 0.26%Met was less than the other groups. Leg muscle rate did not show out quadratic related with Met levels. Abdominal meat rate did not show out quadratic related with Met- levels.There were not significantly between 0.26% and 0.3M%Met,but wre highter than that of 0.36%,0.41%and 0.46%Met..The other groups had no significantly difference.3. Effect of different Met levels on uric acid concentration of 21-42 days broilerUric acid concentration had quadratic related with Met levels.Uric acid concentration raised as Met levels increased ,but then decreased.Uric acid concentration fed a diet containing 0.36% and 0.41%Met was low (p<0.05).Height or low Met dietary increased uric acid oncentration(p>0.05).4. Effect of the manthmatics model on the requirement of Met for the broiler.Based on the broken linear model ,the total Met requirement for the maximum body weight , feed conversion rate, abdominal fat rate, breast muscle rate and the minimum uric acid concentration is 0.358%、 0.359%、 0.338%、 0.415%、 0.356%, respectively. Based on the quadratic multinomial model,the total Met requirement for the maximum body weight, feed conversion rate, abdominal fat rate, breast muscle rate and the minimum uric acid concentration is 0.392%、 0.400%、 0.390%、 0.432%、 0.372%, respectively. Met requirement based on the quadratic multinomial model was highter than that of Based on the broken linear model.更多还原