黄姑鱼一龄幼鱼形态性状对体重的影响分析

随机选取一龄黄姑鱼幼鱼362尾,测量其体重、全长、体长、体厚、体高、头长、尾柄长、尾柄高、吻长、吻尖至背鳍起点长、眼径、眼间距共12个形态学指标。采用相关分析和通径分析方法,揭示了影响黄姑鱼一龄幼鱼体重的主要外部形态性状。结果表明,各形态性状与体重的相关系数均达到极显著水平;影响黄姑鱼一龄幼鱼体重的主要性状是体长、体高、体厚、尾柄高和眼间距;体长对体重的通径系数最大（0.400＊＊）,对体重的决定系数最高（16.00%）;眼间距对体重的直接作用较小（0.066＊＊）。主要是通过间接作用来影响体重（0.627 6）;决定分析的结果和通径分析的变化趋势一致;各形态性状对体重总的决定系数∑d=0.904,它与相关指数R2的数值相等;通过逐步回归分析方法,经偏回归系数显著性检验,建立了体质量为因变量,体长、体高、体厚、尾柄高和眼间距为自变量的多元回归回归方程为：y=-104.906＋4.336 x1＋11.654 x2＋14.015 x3＋7.138 x4＋8.761 x5。

Effects of Morphometric Traits on Body Weight for One-Year Old Nibea albiflora

Nibea albiflora is a high-nutrition and economic valued marine fish species,which is widely distributed in Chinese Korean and Japanese water.N.albiflora has been intensively studied in artificial reproduction,cage-culture and industrial culture.However,development of the aquaculture has been slow down because of overfishing and abstract of fine species in recent years.Needed by fine breed selection,the body selection is a direct indicator to productivity.In the present paper,the relationship between the phenotypic features and the body weight of N.albiflora was studied.362 one-year old N.albiflora were randomly sampled from testing field of marine fisheries research institute of Zhejiang.12 morphometric traits including body weigh（BWH）,total length（TL）,body length（BL）,body depth（BD）,body width（BW）,head length（HL）,tail handle length（THL）,tail handle height（THH）,snout length（SL）,snout to origin of dorsal fin（SG）,interorbital width（IW） and eye diameter（ED） was measured.By path analysis and multiple regression analysis,the main morphometric traits affecting weight of N.albiflora were studied.The result revealed that the correlation coefficient of each morphological trait and body weight were all of very significant difference（P0.01）.Major morphometric attributes that affect the body weight of N.albiflora at one-year old were body length（BL）,body depth（BD）,body width（BW）,nterorbital width（IW）,tail handle height（THH）.Body length（BL） as a key effect had predominant direct effect（0.400＊＊） and determinacy（16.00%） on weigh traits.Nterorbital width（IW） exhibited slight direct effect（0.066＊＊） and significant indirect effect（0.627 6） through other phenotypic features on the body weight.The trend of determination coefficient analysis was similar to that of path analysis.High multiple correlation index（R2=0.904） between phenotypic features and body weight indicated that the selected traits were practically useful.Except the insignificant factors,the multiple regression equation obtained to estim-ate body weigh of N.albiflora as one-year old were： y=-104.906＋4.336 x1＋11.654 x2＋14.015 x3＋7.138 x4＋ 8.761 x5.