Touchburn S, Simon J, Leclercq B
J Nutr. 1981 Feb;111(2):325-35. doi: 10.1093/jn/111.2.325.
Effects of dietary protein or energy level on growth and physiological parameters were investigated in growing chickens selected for high (fat line, FL) or low (lean line, LL) abdominal fat but similar body weight. The FL birds deposited consistently more abdominal fat (about two-fold) and had poorer feed conversion, irrespective of diet. Increasing the ratio of energy to protein increased fat deposition similarly but at different levels. Body weight and feed consumption showed only minor and inconsistent differences and feed consumption following a fast and body temperature in the fed or the fasted-state showed no differences between lines. Fasting plasma glucose levels were similar for both lines at hatching but consistently lower in FL birds thereafter. This was matched by higher fasting plasma insulin levels. A similar relationship was also observed in fed FL birds at 2 weeks of age. Glucose disposal rate was faster in FL birds at 4 and 6 weeks but normal by 8 weeks. The glucose-induced insulin release was higher in FL birds at 6 and 8 weeks, indicating a normal sensitivity to insulin at a young age, with the development of a tissue insulin resistance by 8 weeks of age. The primary mechanism responsible for the fattening of FL birds appears therefore to be greater insulin release from the pancreas of the FL birds soon after hatching.
在体重相似但腹脂含量高（脂肪系，FL）或低（瘦肉系，LL）的生长鸡中，研究了日粮蛋白质或能量水平对生长和生理参数的影响。无论日粮如何，FL系鸡的腹部脂肪沉积始终更多（约两倍），饲料转化率也更低。提高能量与蛋白质的比例会以不同水平相似地增加脂肪沉积。体重和采食量仅表现出微小且不一致的差异，禁食后的采食量以及采食或禁食状态下的体温在品系间无差异。孵化时两品系的空腹血糖水平相似，但此后FL系鸡的空腹血糖水平始终较低。与之对应的是，FL系鸡的空腹血浆胰岛素水平较高。在2周龄的采食FL系鸡中也观察到类似关系。4周龄和6周龄时，FL系鸡的葡萄糖处置率更快，但8周龄时恢复正常。6周龄和8周龄时，FL系鸡的葡萄糖诱导胰岛素释放更高，表明幼龄时对胰岛素敏感，而到8周龄时出现组织胰岛素抵抗。因此，FL系鸡育肥的主要机制似乎是孵化后不久，FL系鸡胰腺释放的胰岛素更多。
