瓯江彩鲤形态特征的两性异形和雌性个体生育力

研究了瓯江彩鲤(Cyprinus carpio var.color)体重和形态特征等19个参数的两性异形及雌性个体生育力.结果表明:除特定体长1龄雌性个体的体高和体重显著小于雄性个体外,其它17个性状不存在显著的雌雄两性异型.在2龄鱼中,雌性个体的头长、头宽、头高、眼后头长、眼间距、尾鳍长、体重和躯干重显著大于雄性个体,而体高却显著小于雄性个体,其它性状也不存在显著的雌雄两性异型;对这9个差异显著的形态特征变量进行主成分分析发现,第一和第二主成分共解释67.6%的变异,体高、体重和躯干重在第一主成分有较高的正负载系数(解释42.9%变异),头宽和眼间距在第二主成分有较高的正负载系数(解释24.7%变异).以年龄、性别为固定效应的两因素方差分析(Two-way ANOVA)显示,1龄鱼第一主成分的分值显著小于2龄鱼,雌性第二主成分的分值显著大于雄性,其它主成分的年龄、性别间无显著差异,两因素交互作片{对第一、第二主成分的分值亦无显著影响.雌性个体的生育力结果表明,瓯江彩鲤的怀卵数量与体长和体重回归关系显著.偏相关分析表明,雌性怀卵数量与体重呈显著的正相关(P<0.004),而与体长的相关不显著(P=0.502).生育力选择是瓯江彩鲤个体大小和局部特征两性异形的主要原因之一.

Sexual Dimorphism in Morphological Traits and Female Individual Fecundity of Oujiang Color Common Carp,Cyprinus carpio var.color

The sexual dimorphism in morphological traits and female individual fecundity of Cyprinus carpio var.color,distributing in Oujiang river base,Zhejiang Province,were analyzed in this paper.The results indicated that body weight and body length from juvenile females with special body length were significantly lower than those of juvenile males,and no significant difference in the other traits between juvenile females and males.The adult females with special body length were significantly larger than adult mal...