Abstract: The metabolism of 250?day?old cocks was studied by means of a 2×2 experimental design of an open return flow respiratory calorimeter for poultry，combined with growth metabolism and fasting metabolism respiratory calorimeter tests. The results showed that the respiratory quotients and caloric production of cell 1 and cell 2 were 1.049，1.104，247.743 and 207.796 kcal/d，respectively，indicating that cell respiration was mainly carbohydrate and fat during feeding. The respiratory quotients and caloric production of cell 1 and cell 2 during hunger strike were 0.855，0.778，184.189 and 155.399 kcal/d，respectively，indicating that the main substrate of cell respiration during hunger strike was protein. Under light condition，the respiratory and heat production of cell 1 and cell 2 were 0.960，0.966，221.198 and 231.643 kcal/d，respectively. Under no light condition，the respiratory and heat production of cell 1 and cell 2 were 0.944，0.916，170.787 and 171.499 kcal/d，respectively. The results showed that chickens showedobvious circadian rhythm，and metabolism was higher in light condition than in dark condition. It can be seen thatunder different lighting conditions，the results of the two cells are similar，and under different feeding conditions，the difference between the two cells is large，but the results in chamber 1 maybe more accurate.

摘要： 利用“禽用开放回流式呼吸测热装置”，采用 2×2 试验设计，结合生长代谢和绝食代谢呼吸测热试验，对 250 日龄公鸡的代谢规律进行了研究。结果表明：采食期间，小室 1 和小室 2 的呼吸商、产热量分别为 1.049、1.104、247.743、207.796 kcal/d，说明在采食期间细胞呼吸的底物主要为碳水化合物和脂肪；绝食期间小室 1 和小室 2 的呼吸商、产热量分别为 0.855、0.778、184.189、155.399 kcal/d，说明在绝食期间细胞呼吸主要底物为蛋白质；光照条件下小室 1 和小室 2 的呼吸商、产热量分别为 0.960、0.966、221.198、231.643 kcal/d，无光条件下小室 1 和小室 2的呼吸商、产热量分别为 0.944、0.916、170.787、171.499 kcal/d，说明鸡呈现出明显的昼夜节律，光照条件下代谢高于黑暗条件。由此可见，在不同光照条件下，两种小室所得结果相近，在不同采食条件下，两种小室差异较大，但小室 1 的结果可能更为准确。

关键词: 呼吸商, 产热量, 呼吸测热, 开放回流呼吸测热装置