红鳍东方鲀(Takifuguru bripes)雌、雄个体的形态特征比较

Comparison of the Morphological Traits Between Male and Female Individuals of Takifugu rubripes

为了比较红鳍东方鲀(Takifugu rubripes)雌、雄个体的形态差异,基于主成分分析、逐步判别分析和T检验的方法,以红鳍东方鲀雌、雄群体的17个比例性状为分析对象进行研究。主成分分析构建了3个反映形态特征信息的综合性指标—主成分1、主成分2和主成分3,贡献率分别为46.776%、27.668%和7.122%,3个主成分累积的贡献率为81.566%,两个群体之间存在明显的偏离;判别分析结果显示,根据各变量对判别函数的贡献大小,筛选出两个比例性状,即体宽/体长、体周长2/体长,利用这两个性状建立起红鳍东方鲀的雌、雄判别模型,对雌、雄共72个个体的判别准确率为81.9%;T检验结果显示,体宽/体长在红鳍东方鲀两性群体间差异极显著(P<0.01),体周长2/体长在红鳍东方鲀两性群体间差异显著(P<0.05)。综合分析实验结果表明,红鳍东方鲀雄性与雌性相比,体形较宽,体周长2较长。红鳍东方鲀雌、雄的形态差异为繁育和选育过程中的性别鉴定提供了新的方法和理论依据。

In this study we analyzed 17 normalized traits of Takifugu rubripes and established the discriminant equations for male and female using T-test and Multivariate Statistical Analysis methods such as Principal Component Analysis and Stepwise Discriminant Analysis. The trait values for morphological analysis were obtained by normalizing individual＇s morphological data to its body length. The Principal Component Analysis generated three principal components of which the contributions were 46.776%, 27.668% and 7.122% respectively, and the cumulative contribution was 81.566%. Most of the female and male individuals could be distinguished in the three-dimensional space composed of the three main components. Two normalized traits, body width/body length and body girth （2）/body length, were selected by Stepwise Discriminant Analysis based on the contribution of variables to the discriminant function. The success rate of the discriminant equations identifying 72 samples was 81.9%. As for the other 38 samples, the success rate was 84.2%. The T-test result of body width/body length between the male and female T. rubripes was highly significant （P〈0.01）, and the result of body girth （2）/body length was also significant （P〈0.05）. Our results demonstrated that the male individuals have wider body width and longer body girth （2） than female. By measuring only three morphological traits, body girth （2）, body width, and body length, we were able to rapidly identify the gender of T. rubripes with a success rate more than 80%. In conclusion, the discriminant equations for male and female could be a simple, novel, and efficient method for sex identification during cultivation and breeding.