镧对黄姑鱼幼鱼促生长作用和成活率影响的研究

Effect of Lanthanum(La^(3+)) on growth and survival rate of Nibea albiflora larvae

为探究镧对黄姑鱼(Nibea albiflora)幼鱼的促生长作用和成活率的影响,本研究设7组不同镧质量浓度处理组,采用不同方程对不同镧质量浓度组的体质量生长拟合。实验结果表明,不同镧质量浓度处理组黄姑鱼幼鱼的生长速度差异显著(P<0.05)。采用线性方程:1.8 mg/L处理组的体质量生长系数最大,为0.011 2,而对照组(0 mg/L)的体质量生长系数最小,为0.009 9;采用多项式方程:1.8 mg/L组全长生长系数的绝对值最大,为3.26,而对照组(0 mg/L)的全长生长系数的绝对值最小,为1.17。镧对体质量增大率、全长增长率和特定生长率、死亡率均有显著的影响(P<0.05),用多项式方程分别对上述生长参数与镧质量浓度(C)之间的相关关系拟合得到,体质量增大率=162.93+42.79C+(–11.62)C^2(R^2=0.95),全长增长率=38.49+21.54C+(–7.27)C^2(R^2=0.90),特定生长率=1.08+0.16C+(–0.04)C^2(R^2=0.93),死亡率=62.91+(–22.88)C+7.19C^2(R^2=0.54)。根据方程,得到最适体质量增大、最适全长增长、最适特定生长、最低死亡率的镧质量浓度分别为1.84、1.48、2和1.59 mg/L。证实,镧可促进黄姑鱼幼鱼的生长及提高成活率,1.48~2 mg/L为黄姑鱼幼鱼的最适生长的镧质量浓度范围。

To investigate the role of La3+in the growth and survival rate of Nibea albiflora larvae,we designed seven different concentration treatment groups of La3+.Results showed that La3+has a significant effect on the larval growth(P<0.05).Statistical analysis revealed correlations between body weight(W)and culture days(d)in the linear equation,wherein the 1.8 mg/L treatment group showed the maximum body weight coefficient of 0.0112,whereas the control group(0 mg/L)showed the minimum coefficient of 0.009 9.Correlations between body length(L)and culture days(d)could be described by the polynomial equation,in which the 1.8 mg/L treatment group showed the maximum length growth coefficient of 3.26,whereas the control group(0 mg/L)showed the minimum length growth coefficient of 1.17.La3+(C)had a significant influence on the body weight growth rate,body length growth rate,specific growth rate,and average mortality rate(P<0.05).The polynomial equations with the correlations are as follows:body weight growth rate=162.93+42.79C+(–11.62)C2(R2=0.95),body length growth rate=38.49+21.54C+(–7.27)C2(R2=0.90),specific growth rate=1.08+0.16C+(–0.04)C2(R2=0.93),and average mortality rate=62.91+(–22.88)C+7.19 C2(R2=0.54).According to the regression equation,the optimal weight growth,the optimum length growth,the optimal specific growth,and the lowest mortality were observed at La3+concentrations of 1.84,1.48,2 and 1.59 mg/L,respectively.This study confirmed that La3+has a growth-promoting action and improves the survival rate of N.albiflora,and the optimum concentration range is 1.48–2 mg/L.