日本沼虾养殖群体主要形态性状对体质量的通径分析

从封闭养殖5代的6月龄日本沼虾群体中随机选取200尾雌虾和70尾雄虾,测定体质量以及全长、体长、头胸甲长、头胸甲宽、头胸甲高、腹部长、第二腹节宽和第二腹节高等表型形态性状,采用相关分析、通径分析和回归分析方法,分析表型形态性状对体质量的影响。结果显示:体质量仍具有最大的选择潜力,雌虾的全长、体长、腹部长等性状和体质量的通径系数达到极显著水平,其中体长对体质量的直接影响和决定程度最大;雄虾的全长、头胸甲高和体质量的通径关系达到极显著水平,全长对体质量的直接影响和决定程度略大于头胸甲高;雌、雄虾所选性状对体质量回归方程的回归关系均达到极显著水平,所选性状与体质量的复相关系数分别为0. 933和0. 930,可见这些性状经过5代封闭养殖后,在雌雄虾中仍是影响体质量的主要自变量指标。

Path analysis of the effects of morphological attributes on body mass in Macrobrachium nipponense

Path analysis was performed on eight morphometric attributes to determine for body mass of Macrobrachium nipponense, which were closed cultured for five years in ponds. The direct and indirect effects of eight attributes included total length, body length, carapace length, carapace width, carapace height, abdomen length, second uromere width and height. Results showed that body mass still had the greatest selection potential. And body mass was significantly correlated with the traits of total length, body length, abdomen length, carapace height and carapace width in female, and with traits of the total length and carapace height in male. Furthermore, body length and total length had substantial direct effects on body mass in female and male respectively. The regression equations were established between the selected traits to body mass for the male and female and the regression coefficient of equations reached the extreme significant level. The multiple correlation coefficients of the five attributes in female prawn and two attributes in male prawn to body mass reached 0.933 and 0.930 respectively, which indicated that the selected traits were the main variable index of body mass. Results suggest that body length in female and total length in male are primary selection criteria for improving body mass in M.nipponense.