光环境因子对循环水养殖系统中大西洋鲑生长和摄食的影响

Effects of different types of environment light on the growth performance and feeding of Atlantic salmon(Salmo salar) in recirculating aquaculture systems

采用正交实验法,研究了不同光色(白光,A1;蓝光,A2;红光,A3)、光周期(24L︰0D,B1;12L︰12D,B2;8L︰16D,B3)和光强(0.88 W/m2,C1;4.55 W/m2,C2;8.60 W/m2,C3)对循环水养殖系统中体质量(850.97±82.77)g的大西洋鲑(Salmo salar)生长和摄食的影响。实验设A1B1C1(1)、A1B2C2(2)、A1B3C3(3)、A2B1C2(4)、A2B2C3(5)、A2B3C1(6)、A3B1C3(7)、A3B2C1(8)、A3B3C2(9)9个处理组,在相应设定条件下饲养180 d。结果表明,在光色为红光、光周期为12L︰12D和光强8.60 W/m2条件下大西洋鲑的成活率最高,但光色、光周期和光强对成活率的影响差异不显著(P>0.05);实验期间各组鱼的相对增重率和肥满度差异均不显著(P>0.05);至第120天,2、5、6组鱼的体长特定生长率显著高于1组(P<0.05);至第180天,1、2、4、7、8组鱼的体质量特定生长率显著高于6组(P<0.05),1、2、3、4、7、8、9组鱼的日增重显著高于6组(P<0.05),9组鱼的体质量变异系数显著低于7组(P<0.05)。9组鱼血浆中生长激素显著高于1、2、3、4、6、7和8组(P<0.05);摄食率、饲料转化效率和饲料系数最佳时的光照条件为:红光、12L︰12D、8.60 W/m2,但光色、光周期和光强对摄食率、饲料转化效率及饲料系数的影响差异不显著(P>0.05)。本实验条件下,较为适宜的光照条件是:红光、12L:12D、8.60 W/m2。

We aimed to explore the effects of different types of light color（i.e., A1, white light;A2, blue light;A3, red light）, photoperiod （i.e., B1, 24L︰0D;B2, 12L︰12D;B3, 8L︰16D） and light intensity （i.e., C1, 0.88 W/m2;C2, 4.55 W/m2; C3, 8.60 W/m2） on the growth performance and feeding of Atlantic salmon （Salmo salar） with initial body weights of 850.97±82.77 g for 180 days in recirculating aquaculture systems （RAS） using orthogonal test methods. Nine treatment groups were designed in the present experiment： A1B1C1（group1）, A1B2C2（group2）, A1B3C3（group3）, A3B3C2（Group4）, A2B2C3（group5）, A2B3C1（group6）, A3B1C3（group7）, A3B2C1（group8）, and A1B1C1（group9）. The re-sults showed that the highest survival rate was found in red light, 12L︰12D and 8.60 W/m2 at the end of the trial, and no significant difference was observed in the survival rates of the experimental groups （P〉0.05）. There were no signifi-cant differences in relative weight gain and condition among the nine groups at each sampling time （P〉0.05）. At day 120, the specific growth rate of body length for groups 2, 5 and 6 were significantly higher than those of group 1 （P〈0.05）. At day 180, the specific growth rate of body weight in groups 1, 2, 4, 7 and 8 were significantly higher than those of group 6 （P〈0.05）, and the daily weight gain of groups 1, 2, 3, 4, 7, 8 and 9 showed higher variation than those of group 6 （P〈0.05）;the coefficient of size variation （SV） in group 9 was lower than in group 7 （P〈0.05）. Additionally, the plasma growth hormone in group 9 was a higher concentration than that of groups 1, 2, 3, 4, 6, 7 and 8 （P〈0.05）. Better food intake（FI）, food conversion efficiency（FCE） and food conversion ratio（FCR） were also observed in red light （12L︰12D） at 8.60 W/m2 at the end of the experiment, while light color, photoperiod and light intensity had no sig-nificant effects on the FI, FCE and FCR between groups（P〉0.05）. Hence, red light （12L︰12D） at 8.60 W/m2 is consid-ered to be a suitable combination of artificial lighting under the experimental conditions described herein.