大菱鲆选育家系雌、雄群体的生长发育差异

采用全长/体长、体高/体长、全长/体高和体质量为评价指标,分别对9~33月龄大菱鲆雌、雄群体在生长发育过程中体型的动态变化及生长性能差异进行了比较。大菱鲆雌、雄群体形态比较结果显示,雌、雄群体的全长/体长、体高/体长、全长/体高在不同发育阶段呈现特有的变化,但在雌、雄群体间,除33月龄的体高/体长和全长/体高差异达到显著水平外,3项指标在不同阶段没有差异或差异不显著,即可以认为,对于统计初始体质量相同或相近的大菱鲆雌、雄群体,全长/体长、体高/体长和全长/体高3个形态比例指标是随发育时间序列同步变化。基于Logistic模型对大菱鲆雌、雄群体生长性能的比较结果显示,雌性群体的拐点月龄、拐点体质量和最大月增重均大于雄性群体;对于雌性和雄性群体的瞬时增长率,除在9~13月龄雌性群体稍低于雄性群体外,13~33月龄的雌性群体均高于雄性群体,且随着生长发育和体质量差异的增大,雌、雄瞬时增长率的差异也呈增大趋势;雄性群体进入快速生长期的始速点和进入缓慢生长期的终速点均比雌性群体提前,雄性群体的快速生长期时间区间长度小于雌性群体,其对应的体质量区间长度也小于雌性群体,雌性群体在快速生长期的月增重显著高于雄性群体。研究表明,大菱鲆雌、雄群体在生长发育过程中存在着显著的生长差异,而形态差异不显著。

Developmental differences between female and male groups in turbot(Scophthalmus maximus)breeding families

The differences between female and male turbot in morphology and growth were compared using total length/body length(TL/BL), body depth/body length(BD/BL) and total length/body depth(TL/BD) as well as body weight.The comparison results of morphology showed that although TL/BL, BD/BL and TL/BD of the two groups presented respective dynamic changes at different growth stages, the differences of the three proportion indexes did not exist or were not significant except that the differences of BD/BL and TL/BD of 33 months of age were significant, namely, TL/BL, BD/BL and TL/BD between female and male groups were fluctuating simultaneously with time series of growth when the initial weight of the two groups were same or similar.The comparison results of the two groups, growth showed that female groups showed later starting point(14.7), inflection point(24.0) and ending point(33.2), heavier weight at inflection(1 443.56 g) and maximum month gain(103.10 g), longer fast-growing period time interval(18.4 months) and fast-growing body weight intervals(1 666.88 g) and heavier month gain(90.39 g) during fast-growing period than those of male groups.Furthermore, the instantaneous growth rates of female groups was higher than those of male group during months 13.1-33.0.The differences of instantaneous growth rates of the two groups showed an increasing trend with accretion of body weight differences during development.The findings suggest that the differences of the two groups in growth are significant and the differences in morphology are not significant.