哲罗鲑形态性状与体重的相关性分析

从20个全同胞家系中随机测量了900尾哲罗鲑（Hucho taimen）幼鱼（1＋龄）的体重、全长、体长、叉长、体高、体宽、头长、头高、头宽、眼径、眼间距和吻长等11个形态性状，采用相关性分析、通径分析、多元分析，计算了以形态性状为自变量对体重为依变量的相关系数、通径系数和决定系数，定量分析了哲罗鲑形态性状与体重的相关性。11个形态性状与体重的相关性均达到显著性水平（R0．05），去除体长、叉长及头长这三个与全长共线性的性状后，进行通径分析，发现眼径和吻长对体重的作用不显著，在剩下的6个性状中，全长对体重的决定作用最大，主要通过直接作用影响体重，其直接作用系数为O．5549，且大于其它5个性状的直接作用之和。这6个性状对体重的复相关系数为0．9643，表明其是影响体重的主要因素。应用多元回归分析，建立以体重为依变量，全长、体高、体宽、头高、头宽、眼间距为自变量的通径方程：log（体重）=-3．9130＋1．7039log（全长）＋0．2626log（体高）＋0．2740log（体宽）＋0．1765log（头高）＋0．3460log（头宽）＋0．262410g（眼间距）。以上通径方程为哲罗鲑亲本的选择和表型性状的理想测量提供了理论依据。

Mathematical Analysis of Effects of Morphometric Attributes on Body Weight in Taimen Hucho taimen

The body weight, total length, standard length, fork length, body height, body width, head length, head height, head width, eye diameter, interorbital width and snout length were measured in 900 over 1-year old Hucho taimen juveniles from 20 full-sib families. The correlation index （R2）, path coefficients （Pi） and determination coefficients （Di） were calculated based on independent variables of morphometric attributes and dependent variables of body weight by correlation analysis, path analysis and multivariate analysis. There were significant difference in all 11 correlation coefficients between each morphometric attribute and body weight （P 〈 0.05）. Exclusion of standard length, fork length and head length attributes that shared the collinear with total length, the path analysis revealed that the eye diameter and snout length had no significant effect on the body weight. Among the remain six attributes, the total length was found to show the significant effect on the body weight with the direct effect efficiency s of 0.5549. Judging by the results of high determination coefficients （R2=0.9643）, the six attributes were the key effective factors to the body weight. The path formula was expressed based on the independent variables of total length, body height, body width, head height, head width, interorbital width and dependent variables of body weight by using multivariate analysis as log （body weight） =-3.9130＋1.7039 log （total length）＋0.2626 log （body height）＋0.2740 log （body width）＋0.1765 log （head height）＋0.3460 log（head width）＋0.2624 log（interorbital width）. These results provided a theoretical basis with selection of taimen broodstock and measurement of the morphometric attributes in aquaculture.