The effect of starvation and refeeding on excretion of nitrogen and phosphorus in Japanese flounder Paralichthys olivaceus( body weight of 69.56 g ±2.35 g) were investigated by still water experiment method in a laboratory at water temperature of( 15.0 ± 1.0) ℃. The results showed that the excretion rate of N and P was sharply decreased in the initial starvation and became relatively stable with the starvation preceeded. Mter the starved fish were refed, the excretion rates of N and P in the starved fish in the treatment groups were returned to those in the control group, indicating that there were significant effect of refeeding on the excretion of N and P( P ＜ 0.05). The maximal N and P excretion rates were found at 10:00 of 4 h after refeeding in the fed and starved fish, and decreased gradually with the minimum at 18:00. There was no significance in diurnal N excretion during the refeeding period(P ＞0.05). However, the average P excretion was found slightly higher (P ＜ 0.05) in the day time than during the night.%采用静水试验法,在水温为(15.0±1.0)℃下,研究了饥饿及再投喂对牙鲆Paralichthys olivaceus幼鱼(体质量为69.56 g±2.35 g)氨氮、活性磷排泄率的影响.结果表明:饥饿初期牙鲆氨氮、活性磷排泄率呈直线下降,随着饥饿时间的延长排泄率处于相对稳定状态;再投喂后,各饥饿处理组牙鲆氨氮、活性磷排泄率快速恢复到对照组水平,摄食对牙鲆氨氮、活性磷排泄率的影响显著(P＜0.05＝.在饥饿和饱食状态下,牙鲆氨氮、活性磷排泄率的峰值均出现在10:00,为摄食后4 h,以后逐渐下降;低谷均出现在18:00;再投喂期间平均氨氮排泄率昼夜差异不显著(P＞0.05),活性磷排泄率白天略高于夜间(P＜0.05).
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