饥饿和再投喂对泥鳅能量代谢的影响

Effects of starvation and refeeding on energy metabolism in oriental weatherfish(Misgurnus anguillicaudatus)

研究了饥饿(20 d)和再投喂(5 d)条件下泥鳅M isgurnus anguillicaudatus的耗氧率、CO2排出率及排氨率的变化。结果表明:随着饥饿时间的延长,泥鳅的耗氧率呈下降趋势,即从饥饿开始时的200μg/(g.h)降至饥饿结束时的138μg/(g.h),下降了31%;CO2排出率呈先上升后下降的趋势,从饥饿开始时的200μg/(g.h)降至饥饿结束时的120μg/(g.h),下降了40%;排氨率则呈先下降后上升的趋势,从饥饿开始时的6.049μg/(g.h)升至饥饿结束时的7.808μg/(g.h),增加了29.1%;氧氮比(O/N)表现出下降趋势,表明泥鳅在饥饿状态下,首先动用脂肪和蛋白质作为主要能源,而后主要利用蛋白质;呼吸熵(RQ)则表现为先上升后下降。恢复投喂后5 d,耗氧率和CO2排出率明显上升,均达到饥饿初始值(180μg/(g.h))的90%;排氨率继续上升,达到9.208μg/(g.h),比饥饿初始值提高了52.2%;O/N和呼吸熵均呈上升趋势。

The experiment was conducted to study the influence of starvation and refeeding on the energy metabolism in oriental weatherfish Misgurnus anguillicaudatus with initial wet body weight of （ 11.62 ± 2.22） g under （18 ± 0.5 ）℃ from April to May, 2004. The results showed that oxygen consumption and CO2 production of the fish starved for 20 days decreased by 31% （from 200 μg/（g · h） to 138 μg/（g · h） ） and 40% （from 200 μg/（g · h） to 120 μg/（g · h）） respectively, while ammonia- N excretion increased by 29.1% （from 6. 049 μg/（g · h） to 7. 808 μg/（ g · h） ） if compared with the initial value; In the course of starvation, the ratio of oxygen to nitrogen （O/N） also decreased, which indicated that lipid and protein were used as first energy source, and then mainly consumed protein; the respiratory quotient （RQ） increased first, and then declined. After 5 - day refeeding, all the metabolism parameters including the oxygen consumption, CO2 production, ammonia - N excretion, O/N and RQ turned to increase if compared with those of fish starved for 20 days.