不同家系中华绒螯蟹幼蟹在室外和室内的生长

Comparative Growth Traits in Different Families of Juvenile Chinese Mitten Handed Crab,Eriocheir sinensis,Cultured in Net Cages Disposed in Ricefields and in an Indoor Tank

2015年6月上旬,将3个家系中华绒螯蟹大眼幼体分别饲养在面积为40m2(6.50m×6.15m)的稻田围隔中,每个围隔约2500尾。2015年7月中下旬,随机从中选取各3个家系的幼蟹,放入室内300L的养殖缸(30只/缸)中对比养殖。2015年8—10月连续测量了幼蟹的头胸甲宽、头胸甲长、体质量,用多重方差分析了环境、家系及生长阶段的性状参数。试验结果表明,养殖环境对A家系幼蟹生长性状的影响不显著(P>0.05),对B家系则极显著(P<0.01),对C家系,除了初始的生长性状影响不显著外(P>0.05),其余均存在显著影响(P<0.05),表明A家系具有一定的环境适应性。家系因素对幼蟹生长性状参数均存在显著影响(P<0.05),表明遗传对于幼蟹的生长具有重要作用。相关分析表明,蟹种的头胸甲宽、头胸甲长在两种养殖环境中均呈极显著正相关(P<0.01),相关系数分别为0.314、0.305;体质量呈不显著正相关(r=0.146,P>0.05),表明以头胸甲宽、头胸甲长为选育指标得到的后代对两种养殖环境有一定的适应性。

Megalopa larvae of A,B and C families of Chinese mitten handed crab（Eriochier sinensis）were reared in a 40m2 net cage（6.50m×6.15m）at a stocking density of 2500 individuals per cage in early June of 2015.Some of the juveniles were randomly sampled from the net cages and comparatively reared in an indoor 300 Ltanks at a stocking density of 30 individuals per tank later July of 2015.Carapace width,carapace length and body weight reared in the juveniles in the ricefields and in an indoor tank were measured in a some 15 day interval from August to October in 2015,and the data above were analyzed by multiple analysis of variance and repeated measures analysis of variances from environmental factor,family factor and the growth traits.The results showed that there was no significant influence of rearing environmental factor on the growth traits in the crab juveniles in family A（P〉0.05）,with very significant influence on those in family B（P〈0.01）,and significant influence on those in family C（P〉0.05）except for at the beginning period of growth（P〈0.05）,indicating that the juveniles in family A had a certain environmental adaptability.Meanwhlie,family factor was found to have significant effects on growth traits of the crab juveniles in different periods（P〈0.05）,which shows that heredity plays an important role in the growth of crab juveniles.The correlation analysis of rearing environments revealed that there was very significant positive correlation between growth traits（carapace width and carapace length）and rearing environment,with correlation coefficients of 0.314 and 0.305（P〈0.01）,and no significant correlation with the body weight（r=0.146,P〉0.05）.The findings indicate that the offspring will have a certain adaptation when carapace width and carapace length are chosen as selection indices in two different rearing environments.