中华绒螯蟹“长荡湖1号”选育第二代扣蟹阶段养殖性能研究

A evaluation on culture performance of second selective generation of Chinese mitten crab(Eriocheir sinensis)“Changdang Lake 1”during juvenile culture stage

为探究中华绒螯蟹(Eriocheir sinensis)“长荡湖1号”A系和B系选育第二代扣蟹的生长性能和养殖效果,在相同养殖条件下,以未选育的养殖群体扣蟹为对照进行了网箱养殖试验。结果表明:(1)大眼至豆蟹阶段,不论是平均体质量、增重倍数还是成活率,“长荡湖1号”B系均显著高于对照组(P<0.05),“长荡湖1号”A系较对照组具有一定的优势,但差异不显著。(2)扣蟹阶段,“长荡湖1号”B系的平均体质量均显著高于对照组(P<0.05),“长荡湖1号”A系9月份体质量与对照组接近,其他月份均显著高于对照组(P<0.05)。就生长速度而言,在6—7月期间,“长荡湖1号”A系和B系的生长速度显著快于对照组(P<0.05)。(3)“长荡湖1号”B系养殖效果最佳,具体表现在养殖产量和成活率最高,显著高于其他两个组,且1龄早熟率和饲料系数最低(P<0.05)。(4)就规格分布而言,“长荡湖1号”A系和B系的体质量在3.00~5.99 g和6.00~8.99 g两个区间内的比例低于对照组,在12.00~14.99 g和≥15.00 g两个区间内显著高于对照组(P<0.05),即A系和B系大规格蟹所占的比例相对更高。综合评价,“长荡湖1号”A系和B系选育第二代在扣蟹阶段成活率高,平均规格大,其余生长性能也优于未经选育的对照组。

To evaluate the breeding effect of the second generation(G2)of“Changdang Lake 1”Strain A and Strain B Chinese mitten crab(Eriocheir sinensis),the juvenile culture experiment was conducted with the unselected population as control.The results showed that:(1)The average body mass,weight gain multiple and survival rate of Strain B were significantly higher than that of control group during the pea-sized juvenile rearing stage(P<0.05),and Strain A also had higher growth performance than the control but no significant difference was observed.(2)The average body weight of crabs in Strain B has always been significantly higher than that of control group during the pea-sized juvenile and coin-sized juvenile culture period(P<0.05).The average body weight of Strain A was also significantly higher than the control with the exception of September(P<0.05),and the growth rate of both Strain A and B were significantly higher than the control between June and July(P<0.05).(3)Crabs in Strain B showed the highest culture performance,in terms of significantly higher survival and yield,as well as significantly lower precocious rate and feed coefficient ratio(P<0.05).(4)For size distribution,the proportion of Strain A and B was lower than that of the control group in the intervals of 3.00-5.99 g and 6.00-8.99 g,and significantly higher than the control in the intervals of 12.00-14.99 g and≥15.00 g(P<0.05).Overall,“Changdang Lake 1”G2 has the advantages of fast growth,high survival rate and large average size at the juvenile culture stage.