12月龄多鳞鱚形态性状对体质量的影响

【目的】研究12月龄多鳞鱚(Sillago sihama Forssk?l)形态性状与体质量之间的关系,筛选适用于选育的主要形态性状。【方法】测定12个形态性状与体质量的表型参数,通过通径分析、相关分析和多元回归分析估计主要性状对体质量的直接影响和间接影响。【结果】12月龄多鳞鱚13个性状之间的相关系数均达到极显著水平(P<0.01)。通径分析表明,体高(X1)、体厚(X2)、眼径(X7)、体长(X10)和背鳍前长(X11)对体质量(Y)有明显的直接影响;除体长外,其他生长性状对体质量的直接影响均小于它们对体质量的间接影响,同时,体长对体质量的直接影响最大。相关分析表明,上述5个主要性状是体质量变化的主要影响因素。体长对体质量的单独决定系数最大(0.331),5个主要性状对体质量的总决定系数为0.928。建立的以主要性状为自变量、体质量为因变量的回归方程为Y=-13.339+2.913X1+3.352X2-4.467X7+1.473X10+0.763X11。【结论】体长、体厚、眼径、体高和背鳍前长等5个主要性状是影响多鳞鱚体质量的核心性状,其中体长影响最大。

Effects of Morphological Traits on Body Weight in 12-Month-Old Silver Sillago(Sillago sihama Forsskål)

【Objectives】To investigate the relationship between morphological traits and body weight of 12-month-old Silver sillago(Sillago sihama Forssk?l)and determine the main traits suitable for breeding.【Method】Phenotypic traits were measured for 12 morphological traits and body weight.The direct and indirect effects of the selected traits were estimated by path analysis,correlation analysis,and multiple regression analysis.【Result】The correlation coefficients between 13 traits among 12-month-old S.sihama reached highly significant level(P<0.01).Path analysis indicated that body depth(X1),body thickness(X2),eye diameter(X7),body length(X10)and pre-dorsal length(X11)significantly and directly affected body weight(Y).The direct effects of morphological traits on body weight were smaller than the indirect effects except for body length,which had the highest direct effect.The correlation coefficients indicated that these five traits were the main factors affecting body weight.Body length had the largest single determination coefficient(0.331),while the total determining coefficient of 5 main traits was 0.928.Using stepwise multiple regression,the following regression equation was established:Y=-13.339+2.913X1+3.352X2-4.467X7+1.473X10+0.763X11.【Conclusion】The five selected key traits,named body depth,body thickness,eye diameter,body length,and pre-dorsal length,were the core decisive morphological traits on body weight,and body length had a greater impact.