辽河和闽江水系中华绒螯蟹扣蟹在成蟹阶段的养殖性能比较

Comparison of Culture Performance of Juveniles Mitten Handed Crab (Eriocheir sinensis) Derived From Liaohe River and Minjiang River in Food Crab Culture

2018年3—11月,将体质量(7.83±0.72)g和(7.53±0.39)g的雌雄辽河水系中华绒螯蟹Eriocheir sinensis扣蟹和体质量(5.06±0.74)g和(5.21±0.49)g雌雄闽江水系中华绒螯蟹扣蟹饲养在42m×35m×1.2m、种植伊乐藻Elodea nuttallii的两口池塘中,密度约为1.2～1.3只/m2,常规方法养殖,比较辽河和闽江水系绒螯蟹扣蟹在成蟹阶段的养殖性能。结果显示:辽河蟹平均终体质量大于闽江蟹,成活率和产量较高;3—5月和7—9月闽江蟹增重率(WGR)和特定生长率(SGR)高于辽河蟹。辽河雌蟹全部完成生殖蜕壳时间早于闽江蟹一个月,而雄蟹则提前半个月左右。9—11月,闽江蟹性腺指数(GSI)增加量高于辽河蟹。11月初辽河蟹总可食率(TEY)显著高于闽江蟹(P<0.05),但出肉率(MY)无显著差异(P>0.05)。闽江蟹中体质量<50g的雌蟹和≥200g的雄蟹的百分比较高。综上所述,辽河蟹全部完成生殖蜕壳时间早于闽江蟹。虽然闽江蟹性腺发育较晚,但其性腺发育速度较快。本实验为进一步挖掘优异种质资源和新品种培育奠定了理论和实践基础。

Female and male juvenile Chinese mitten handed crab(Eriocheir sinensis)derived from Liaohe River[Liaohe crab,with body weight of(7.83±0.72)g and(7.53±0.39)g]and derived from Minjiang River[with body weight of(5.06±0.74)g and(5.21±0.49)g]were reared in two 42 m×35 m×1.2 m ponds planted with aquatic plant Elodea nuttallii at a stocking density of1.2~1.3/m2 from March to November 2018 to investigate the effect of juvenile Chinese mitten handed crab from different rivers on culture performance in food crab culture.The results showed that Liaohe crab had higher average final body weight than Minjiang crab did,thus higher survival rate and yield,even though Minjiang crab had slightly higher weight growth rate(WGR)and specific growth rate(SGR)from March to May and from July to September than Liaohe crab did.There was one month earlier puberty molting in female Liaohe crab than that in female Minjiang crab and about half a month earlier in male Liaohe crab than that in male Minjiang crab.Minjiang crab had higher increase in gonadosomatic index(GSI)from September to November than Liaohe crab did,while Liaohe crab had significantly higher total edible yield(TEY)in early November than Minjiang crab did,without significant difference in meat yield(MY)(P>0.05).The higher percentage of female crab with body weight less than 50 g and male crab with body weight more than 200 g was observed in Minjiang crab.In conclusion,Liaohe crab all completed puberty molting earlier than Minjiang crab,which had late gonadal development,with rapid developmental rate.The findings provide a theoretical and practical foundation for further development of excellent germplasm resources and breeding.