【作者】 方立超；

【导师】 宋代军； 董国忠；

【作者基本信息】 西南农业大学 ， 兽医产科学， 2001， 硕士

【摘要】 为了探索不同的饲粮能量、蛋白质水平对肉鸡生长发育及其肌肉品质的影响，试验以艾维茵肉鸡为试验动物，采用3×3（能量×蛋白质）因子试验设计，研究了不同的饲粮能量水平（低、中、高）和蛋白质水平（低、中、高）下肉鸡的生产性能、肉质、痛风症发生率和睾丸发育。饲粮能量和蛋白质的低、中、高三个水平分别均是NRC（1994）肉仔鸡饲养标准中能、蛋水平的80％、100％、120％，即能量水平（MJ/kg）分别为10.71、13.39、16.07；蛋白质水平（％）0～3周分别为18.4、23.0、27.6；4～8周分别为16.0、20.0、24.0。试验结果表明：（1）饲粮能量水平增加，肉鸡平均日增重增加，饲料转化率减小，低能与中、高能量间差异均显著（P＜0.01），中、高能量间差异不显著（P＞0.05）。蛋白质水平在一定范围内增加，肉鸡平均日增重增加，饲料转化率下降，蛋白质水平进一步增加，肉鸡平均日增重减小，饲料转化率增加，但变化均不显著（P＞0.05）。所有处理中高能中蛋白组试鸡平均日增重最大，为0.044±0.003kg，饲料转化率最小，为2.12±0.13；低能低蛋白组试鸡平均日增重最小，为0.038±0.018kg，饲料转化率最大，为2.47±0.12。（2）肉鸡胸肉钙激活蛋白酶（Calpains）活性随饲粮能量或蛋白质水平的增加而减小（P＜0.01），各处理中高能中蛋白组试鸡胸肉Calpains的活性最小，低能低蛋白组胸肉Calpains的活性最大。胸肉Calpains活性与肉鸡生长速度间有负相关关系存在。（3）饲粮能量或蛋白质水平增加，肉鸡胸肌纤维密度减小、直径增大（P＜0.01）。所有处理中，高能中蛋白组试鸡胸肌纤维密度最小、直径最大，低能低蛋白组试鸡胸肌纤维密度最大、直径最小。胸肌纤维密度与肉鸡生长速度间有中等程度负相关关系（0.05＜P＜0.1），胸肌纤维直径与生长速度间有中等程度正相关关系（0.05＜P＜0.1）。（4）使肉鸡生长速度过高的饲粮能量和蛋白质水平会使鸡肉嫩度下降。（5）饲粮能量水平增加，鸡肉水分含量减少，但鸡肉脂肪沉积持续增加。饲粮蛋白质水平增加，鸡肉中粗蛋白质含量增加，胸肌系水力增加，蛋白质水平过高也会增加鸡肉脂肪沉积。为获得较好肉质的饲粮能量水平不宜过高，蛋白质水平不能过低。（6）高蛋白饲粮易诱发和加剧肉鸡痛风症。饲粮能量水平增加，对肉鸡痛风症发生率有一定促进作用。（7）饲粮能量水平过低或蛋白质水平过高，对肉用雄仔鸡睾丸相对生长速度及其曲细精管的发育有一定阻碍作用。肉用雄仔鸡睾丸相对生长速度越大，其曲细精管的发育程度越大。更多还原

【Abstract】 In order to seek the influence of various content of dietary energy and protein on the development of broilers and their meat quality, a 3 X 3 (Energy X Protein) factoral experiment was designed to study the performance, meat quality, incidence of gout and development of testis of broilers under various dietary energy and protein levels. The lows medium and high dietary energy levels are 80%~ 100%~ 120% of the NRC (1994) standard energy level respectively, the low~ medium and high dietary protein levels are also 80%~ 100%~ 120% of the NRC (1994) standard protein level respectively, that is the dietary energy levels are 10.71(MJ/kg).. 13.39(Mi/kg)~ 16.07(MJ/kg) accordingly, while dietary protein levels are 1 8.4%~ 23.0%. 27.6% respectively during 0 to 3 weeks; during 4 to 8 weeks, the levels are 16.0%~ 20.0%~ 24.0% accordingly. Results showed: (l)With the increasing of the levels of dietary energy, the average daily gain (ADG) increased and the feed conversion rate (FCR) decreased in broilers, there抯 significant difference between low and medium or high energy (P<0.01), but the difference between the medium and high energy was not significant (P>0.05). When dietary protein levels were increasing in a certain of range, the ADG increased and FCR decreased, while the protein levels still increased, the ADG decreased and FCR enhanced (P>0.05). Among all treatments, the ADG of high energy medium protein treatment was the biggest (0.044?.003kg) and the FCR was the smallest (2.12?.13); the smallest ADG and the biggest FCR were in low energy low protein treatment, that was 0.038 2 ?.018kg~ 2.47 ?.12 respectively. (2) With the increasing of dietary energy or protein levels, the activity of Calpains in broilers?breast meat decreased (P<0.0 1), the activity of Calpains in high energy medium protein treatment was the smallest of all treatments, while the biggest is in low energy low protein treatment. There抯 negtive relativity between the activity of Calpains and the growth rate of broilers. (3)With the enhancing of dietary energy or protein levels, the fiber density of breast meat reduced, but the fiber diameter increased (P<O.O 1). Among all treatments, the broilers?breast meat in high energy and medium protein treatment had the smallest fiber density and the biggest fiber diameter, while the broilers?breast meat in treatment of low energy low protein had the biggest fiber density and the smallest fiber diameter. There抯 medium negtive relativity between the breast meat fiber density and the growth rate of broilers (0.05<P<0.l), there抯 medium positive relativity between the breast meat fiber diameter and the growth rate of broilers (0.05<P<0.l). (4)The dietary energy and protein levels that made growth rate of broilers too high can reduce the tenderness of the fowl meat. (5)When the dietary energy levels were increasing, the water content in fowl meat decreased, but the fat deposition would increase continuously. When the dietary protein levels were increasing, the protein content in fowl meat increased and the water holding capacity of meat also increased, but fat deposition would increase too when the level of dietary protein was too high. In order to gain better meat quality, the dietary energy levels shouldn抰 be too high, while the protein levels can抰 be too low. (6) High protein level dietary was liable to induce or aggravate the incidence of gout in broilers. Increasing the dietary energy levels would help increase the incid更多还原