| 摘要: |
| 于1994年8-11月进行4次黑鲷幼鱼摄食－生长实验，平均水温为26.8，24.4，20.1和14.8℃，每次实验分4个日粮水平（停食-饱食），分别对单位体重日氮摄取、粪便氮、氮排泄和氮生长进行测定和估计。结果表明，氮收支各组分的单位体重日平均量随日粮水平的降低而减少，氮排泄、氮生长与氮摄取、氮吸收分别呈显著的线性正相关；氮收支组分以占氮摄取百分比表示时，粪便氮、氮排泄随日粮水平的降低而增加，氮生长则是现不同的变化趋势。同时，对黑鲷幼鱼在不同的日粮水平下的氮生长效率和吸收效率进行探讨。 |
| 关键词: 黑鲷 氮收支 日粮水平 |
| DOI： |
| 分类号: |
| 基金项目:日粮水平对黑鲷幼鱼氮收支的影响 |
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| EFFECT OF RATION LEVELS ON NITROGEN BUDGET IN JUVENILE BLACK PORGY (SPARUS MACROCEPHALUS) |
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LI Jun,XU Shi-hong,XUE Yu-ping
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1.Institute of Oceanology, The Chinese Academy of Sciences, Qingdao, 266071;2.Qingdao Education College, Qingdao, 266071
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| Abstract: |
| Four feeding-growth experiments on juvenile black porgy (Spams macrocephalus) were carried out during August-November in 1994 at a mean seawater temperature of 26.8°C, 24.4°C, 20.l°C and l4.8°C, respectively. The fish, reared in 801 aquarium (pH = 8.0, salinity = 32), were fed Ammodytes personatus at 4 ration levels from starvation to ad libitum. The nitrogen intake, faeces and retention were measured and the nitrogen excretion were calculated using the nitrogen balance equation (CN = FN + UN + GN). The nitrogen intake [mg/(g*d)] increased with ration levels (%). Nitrogen faeces [mg/(g*d)] also increased with ration levels at 26.8°C and 24.4°C, but a maximum appeared in the second highest ration levels at 20.l°C and l4.8°C. The relationships between the nitrogen excretion and ration levels are similar to those between nitrogen intake and ration levels. At the maximum ration, nitrogen intake, faeces and retention [mg/(g*d)] decreased with decreasing temperature and increasing body weight. At starvation the nitrogen excretion [mg/(g*d)] changed a little and ranged 1.04-1.41 mg/(g*d).
The nitrogen budget for the black porgy changed with ration levels. The nitrogen excretions as percentage of nitrogen intake are the highest among the components in the nitrogen balance equation, at the maximum rations the nitrogen excretion decreased with decreasing temperature and increasing body weight. The nitrogen excretion (%, nitrogen intake) was positively correlated with ration levels at 26.8°C and 14.8°C. The nitrogen retention (%, nitrogen intake) efficiency decreased with decreasing ration levels, but a maximum appeared at 4.07% of ration level, not the maximum ration, at 24.4°C. At the maximum ration, the nitrogen retention efficiencies changed in the range of 5.81%-34.20%. The nitrogen retention (mg/d) was positively correlated to nitrogen intake (mg/d) and nitrogen absorption (mg/d). |
| Key words: Sparus macrocephalus, Nitrogen budget, Ration level |
