养殖密度对点篮子鱼生长性能的影响

Effect of Stocking Density on Growth of Speckled Spinefoot Siganus guttatus

研究了水温25～27℃下，4种养殖密度（2．48 kg/m3、4．95 kg/m3、7．80 kg/m3、10．20 kg/m3）对平均体质量（31．30±1．63） g的点篮子鱼生长、摄食和行为的影响。试验结果表明，养殖密度为2．48～4．95 kg/m3时，点篮子鱼生长与密度呈正相关，超过其范围，呈负相关。不同养殖密度的生长参数显示，4．95 kg/m3组显著高于2．48 kg/m3、7．80 kg/m3、10．20 kg/m3组（ P＜0．05）。4．95 kg/m3组生长最快，体质量和体长达到最大值，分别为（63．11±2．52） g和（12．80±0．98） cm ；10．20 kg/m3组生长最慢，体质量、体长分别为（50．73±4．53） g和（11．90±1．03） cm。点蓝子鱼摄食率随养殖密度增大而降低，2．48 kg/m3组摄食率最高，为1．53％，10．20 kg/m3组摄食率最低，为1．32％。4．95 kg/m3组饲料系数显著低于2．48 kg/m3、7．80 kg/m3、10．20 kg/m3组（ P＜0．05）。点篮子鱼的放养密度为4．95 kg/m3时，可以获得较好的生长性能。

Speckled spinefoot Siganus guttatus juveniles with body weight of （31 .30 ± 1 .63 ） g were stocked and reared in an indoor tank at the initial stocking density of 2 .48 （group A） ,4 .95 （group B） , 7 .80 （group C） and 10 .20 （group D） kg/m3 at water temperature of 25~27 ℃ for 60 days .The positive relationship between growth and stocking density was found within the rearing biomass of 2 .48~4 .95 kg/m3 .Beyond that density ,there was a negative relationship between growth and stocking density .The grow th parameters revealed that the fish in group B had significantly better grow th than the fish in groups A ,C ,and D （ P 〈0 .05 ） ,with the maximal body weight of （63 .11 ± 2 .52） g and the maximal body length of （12 .80 ± 0 .98） cm .The fish in group D had the least growth [body weight （50 .73 ± 4 .53） g and body length （11 .90 ± 1 .03） cm] .Food intake were found to be significant decrease with increase in stocking density ,with the maximum in group A （1 .53% ） and the minimum in group D （1 .32% ） .There was significantly lower food conversion ratio in group B than in groups A ,C ,and D （P〈0 .05） .It is recommended that the optimal stocking density be of 4 .95 kg/m3 for speckled spinefoot Siganus guttatus .