摘要:
Thirty one year-old sutchi catfish Pangasius sutchi were randomly sampled for measurement of morphometric attributes on growth of the fish, including body weight, total body length, body length, body height, body width, interorbital diameter, head length, head height, head width, snout length, caudal peduncle length and caudal peduncle depth. Morphometric effects on body weight of the fish were studied using correlation analysis, path analysis and regression analysis. The correlation analysis showed that first there was a very significant relationship between body weight and morphological traits except for snout length (P<0.01). Secondly the four morphometric attributes (total length, body width, head width, caudal peduncle depth) were retained, and the value of multiple correlation index R2 was 0.939. Thirdly the multiple regression equation to estimate the body weight was expressed as Y=-458.204+0.997X1+6. 610X8+2.506X4 + 2.825 X11 where X1= total body length (mm), X8= head width(mm), X4= body width (mm), andX11= caudal peduncle depth (mm), which provided a theoretical basis for sutchi catfish breeding.%选取1龄淡水鲨鱼(Pangasias sutchi Fowler)30尾,测量其体质量、全长、体长、体高、体宽、眼间距、头长、头高、头宽、吻长、尾柄长和尾柄高等12个形态性状,采用相关分析、通径分析和逐步回归分析的方法研究了各性状对体质量的影响效果.结果表明,(1)经相关分析,淡水鲨鱼各形态性状(除吻长)与体质量的相关系数均达到极显著水平;(2)经通径分析,保留了全长、头宽、体宽和尾柄高4个达到显著水平的形态变量,所得相关指数为:R2-2=0.939;(3)经逐步多元回归分析,建立最优回归方程为:Y=-458.204+ 0.997X1 +6.610X8 +2.506X4+2.825X11,式中X1、X8、X4、X11分别为全长(mm)、头宽(mm)、体宽(mm)和尾柄高(mm),为淡水鲨鱼的育种工作提供了重要的理论依据.