光色、光照度和光周期对大菱鲆幼鱼生长和摄食的影响

Effects of light color,light intensity and photoperiod on growth and feeding of juvenile turbot(Scophthalmus maximus)

为研究养殖过程中光照环境(光色、光照度和光周期)对大菱鲆(Scophthalmus maximus)幼鱼生长和摄食的影响,采用初始体质量为(3.17±0.07)g的大菱鲆幼鱼为研究对象,共设置5种颜色的LED光源(冷白、红色、蓝色、绿色和暖白),并在冷白光源下设计5种光照度[600、300、100、25 lx和黑暗对照(0 lx)]和5种光周期(24L∶0D、16L∶8D、12L∶12D、8L∶16D和黑暗对照),养殖试验周期为65 d,试验结束后,对大菱鲆幼鱼的存活率、特定生长率和饵料系数进行测定,同时对生长激素(GH)、胰岛素样生长因子-1(IGF-1)及神经肽Y(NPY)的水平等进行综合分析。结果表明:红色光源处理组大菱鲆幼鱼出现了较多的死亡,但光色、光照度和光周期对大菱鲆幼鱼的存活率未产生显著影响(P>0.05),红色光源处理组幼鱼的生长和摄食性能显著低于冷白和绿色光源处理组(P<0.05);光照度300、100 lx处理组幼鱼的生长和摄食性能较高且显著高于600 lx处理组(P<0.05),持续光照组(24L∶0D)幼鱼的生长和摄食性能显著低于12L∶12D、8L∶16D处理组和黑暗对照组(P<0.05)。研究表明,在大菱鲆养殖过程中要尽量避免使用红色光源,大菱鲆幼鱼适宜在较弱的光照(25~300 lx)环境中生长,强光照会抑制其生长和摄食,短光周期(0~12 h光照)相对于长光周期更利于大菱鲆幼鱼的生长和摄食。

In order to evaluate effects of light environment(light color,light intensity and photoperiod)on growth and feeding of juvenile turbot(Scophthalmus maximus)during culture,juvenile turbot with initial body weight of(3.17±0.07)g was reared in a flowing water tank of 85 cm×75 cm×60 cm under cold white,red,blue,green,and warm white LED light,and light intensity of 600,300,100,25 lx and the dark control and photoperiod of 24L∶0D,16L∶8D,12L∶12D,8L∶16D and the dark control at cold white light and water temperature of(18.3±0.5)℃for 65 days.At the end of the experiment,the survival rate,specific growth rate,feed conversion ratio and the levels of GH,IGF-1,and NPY were comprehensively analyzed.The results showed that there was higher mortality of juvenile turbot in the red light source group,without significant effect of the light color,light intensity and photoperiod on the survival rate(P>0.05).The juvenile turbot had significantly lower growth and feeding performances in red light source group than those in cold white and green light source groups(P<0.05).The growth and feeding performances of juvenile turbot were shown to be significantly higher in 300 and 100 lx groups than those in 600 lx group(P<0.05).The juvenile turbot had significantly lower growth and feeding performances in continuous light group(24L∶0D)than those in 12L∶12D,8∶16D and dark control groups(P<0.05).The findings suggest that the use of red light be avoided during the culture of juvenile turbot.The low light intensity(25-300 lx)is suitable for the growth and feeding of juvenile turbot,while the high light intensity inhibits the growth and feeding.The short photoperiod(0-12 h light)appears to be more conductive to the growth and feeding of juvenile turbot than long photoperiod.