为了解盐度对褐菖鲉Sebastisucus marmoratus幼鱼生长和代谢的影响,在室内水泥池 ( 6. 5 m×2. 5 m)、水深1. 3 m的条件下进行了不同盐度 ( 5、 7. 5、 10、 15、 20、 25、 30) 对体质量为 (3. 65± 0. 82) g褐菖鲉幼鱼特定生长率、成活率、摄食率、饲料系数的影响试验,以及在水浴静水条件下,不同盐度对耗氧率和排氨率的影响试验,养殖试验共进行8周.结果表明: 褐菖鲉幼鱼在10、 15、 20盐度组中生长较好,成活率分别为97. 50%、 98. 33%、 91. 67%,体质量特定生长率分别为1. 904、 2. 001、 2. 077%/d; 5、7. 5和30盐度组褐菖鲉幼鱼成活率分别为0%、 19. 17%、 76. 67%,均显著低于10、 15、 20盐度组 ( P<0. 05);各组褐菖鲉幼鱼饲料系数为1. 230~1. 367,其中15、 20和25盐度组饲料系数均显著低于7. 5和30组 (P<0. 05),而10、 15、 20、 25盐度组间无显著性差异 ( P>0. 05);各组褐菖鲉幼鱼摄食率为1. 282~2. 157%/d,其中15、 20和25盐度组摄食率均显著低于7. 5和30盐度组 (P<0. 05),而10、 15、 20、 25盐度组间无显著性差异 ( P>0. 05);在盐度为7. 5~30范围内,褐菖鲉幼鱼耗氧率 ( OR) 和排氨率 (AR)均随着盐度的增加而升高,分别在盐度为 15 和 25 时达到峰值,分别为 0. 137 mg/ ( g·h) 和 10. 406 μg/ (g·h),之后随盐度的增加而降低,耗氧率与盐度呈一元二次函数关系,即y＝－0. 0002x2+0. 0091x+0. 0512 (R2＝0. 9287);褐菖鲉幼鱼的O/N值范围为12. 160~16. 415.研究表明,褐菖鲉幼鱼具有较强盐度耐受能力,可通过调节生理代谢水平适应低盐或高盐水体,比较适合其生长和代谢的最适盐度范围为15~25.%Specific growth rate ( SGR), survival rate, food intake ( FI) , food conversion ratio ( FCR) , oxygen consumption rate( OR) and ammonia excretion rate ( AR) were determined in juvenile marbled rockfish Sebastisu-cus marmoratus with body weight of (3.65±0.82)g in an indoor tank of 6.5 m×2.5 m×( water depth 1.3 m) with a salinity of 5, 7.5, 10, 15, 20, 25, and 30 at water temperature of 19－28℃ for 8 weeks in order to investigate the effect of salinity on growth and metabolism of marbled rockfish. The results showed that the juveniles had better growth at a salinity of 10, 15 and 20, with survival rate of 97.50%, 98.33% and 91.67%, and SGR of 1.904, 2.001 and 2.077%/d, respectively. However, there was significantly lower survival rate at a salinity of 5 ( 0%) , 7.5 (19.17%) and 30 (76.67%) than that at a salinity of 10, 15, 20 (P<0.05). The FCR was varied from 1.230 to 1.367, significantly lower at water salinity of 15, 20 and 25 than at 7.5 and 30 ( P<0.05), without significant difference among the salinity at 10, 15, 20 and 25 ( P>0.05) . The FI was shown to be changes from 1.282%/d to 2.157%/d during the experiment, significantly lower at water salinity of 15, 20 and 25 than at water salinity of 7.5 and 30 ( P<0.05) , without significant difference between each group at water salinity of 10, 15, 20 and 25 ( P>0.05) . The OR and AR was increased with the increase in water salinity within the water salinity range of 7.5－30 first, and then decreased with the increase in water salinity, the peak values 0. 137 mg/( g·h) , and 10. 406 μg/( g·h) at a salinity of 15 and 25. The OR ( y) showed relationship with water salinity ( x) as y＝－0.0002x2+0.0091x+0.0512 ( R2＝0.9287), with O/N value of 12.160－16.415 in the fish. In conclusion, marbled rockfish juveniles have strong salinity tolerance and can adapt to low salt or high salt water by regulating physiological me-tabolism level, and it is suggested that a salinity of 15－25 be the optimum salinity range for growth and metabolism in marbled rockfish.
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