Effects of stocking density on growth of juvenile Polyodon spathuln reared in net cage

A study on the effect of stocking density on the growth of juvenile Polyodon spathuln reared in net cage was conducted.The initial stocking density was 30,40,50 and 60 individuals/m3,respectively.A 16-day rearing experiment was conducted in this study.The results showed stocking density had some effects on the growth of juvenile P.spathuln.The survival rate was 85.41%,81.66%,76.08% and 80.27%,respectively.The final body weight,specific growth rate(SGR),daily weight gain(DWG) and weight growth rate(WGR) decreased with the increasing of stocking density,while the net yield(NY) increased with the increasing of stocking density.The growth of juvenile P.spathuln at different stocking density was allometry(b3).There were no significant difference between the final coefficient of size variation(SV) and initial SV at four stocking density.The growth efficiency of 30 individuals/m3 group was the largest,while the yield of 60 individuals/m3 was the highest.