黄颡鱼形态性状对体重的影响效果分析

选取了初孵仔鱼100日龄的黄颡鱼526尾,测定了全长、体长、尾柄长、尾柄高、体高、头长、头宽和体重等8项性状。采用相关分析、通径分析和多元回归分析方法对黄颡鱼8个形态性状与体重进行相关性分析。剔除了对体重影响不显著的尾柄长,计算了其他性状为对体重的相关系数、通径系数、决定系数及相关指数等,并建立所测性状对体重的回归方程。结果显示:黄颡鱼所测7个形态性状与体重的相关系数均为极显著水平(P0.01);而剔除尾柄长后,其余性状对体重的通径系数也均达到极显著水平;所选形态性状对体重的决定系数为R2=0.915,表明主要自变量都已被纳入。通过直接作用与间接作用的分析,明确全长、体长与头长是影响体重的主要自变量,其中体长的作用最大。

Analysis of Effects of Morphometric Traits on Body Weight of Yellow Catfish Pelteobagrus fulvidraco

To study the effects of morphological attributes on body weight（Y） of yellow catfish, 526 fry 100 days after hatch individuals were sampled for measuring seven metric traits, including the total length（X1）, body length（X2）, caudal peduncle length（X3）, caudal peduncle depth（X4）, body depth（X5）, head length（X6） and head breadth（X7）. The relationship between morphological attributes and body weight（Y） was quantified by correlation analysis, path analysis and multiple regression analysis to determine the major morphological attributes. Caudal peduncle length（X3） was eliminated from the variable data set because it was non-significant with body length. Seven metric traits were used as independent variables, and body weight（Y） was used as a dependent variable for path analysis. Path coefficients, determination coefficients and correlation index were calculated in path analysis. The results showed that all seven correlation coefficients between each metric traits and the weight achieved were all very significantly different（P〈0.01）. The path coefficients except caudal peduncle length（X3） to the body weight（Y） all reached a level of significance. These attributes were very indicative of determining the body weight（Y）. Judging from the result of high correlation index（R2=0.915）, direct effect and the indirect effect, total length（X1）, body length（X2） and head length（X6） were selected, and the body length（X2） was key effective factor on body weight（Y）.