不同规格中华绒螯蟹亲本子一代在扣蟹阶段养殖性能的比较研究

为探究中华绒螯蟹(Eriocheir sinensis)亲本规格对其子代在扣蟹阶段养殖性能的影响,本试验在相同的养殖环境下将4种规格河蟹亲本(规格I:雌90~110 g、雄140~160 g;规格Ⅱ:雌115~135 g、雄160~180 g;规格Ⅲ:雌140~160 g、雄220~240 g;规格Ⅳ:雌190~210 g、雄290~310 g)所产的大眼幼体养殖至扣蟹,并比较各组扣蟹的体质量、增重率、特定生长率、成活率及最终产量差异。试验结果显示:(1)不同规格的河蟹亲本,其子一代在大眼幼体至豆蟹阶段的平均体质量、成活率以及增重倍数均无明显差异(P>0.05);(2)在豆蟹至扣蟹养殖阶段,各组幼蟹的生长速度差异大体上与其亲本规格的差异相一致,其中Ⅰ组幼蟹在8—10月期间的平均体质量均显著低于Ⅳ组(P<0.05);(3)养殖效果方面,各组扣蟹平均规格和最终产量均随着亲本规格的提高而提高,其中Ⅳ组扣蟹的最终平均体质量显著高于Ⅰ组扣蟹(P<0.05);(4)就规格分布而言,Ⅳ组扣蟹2.00~3.99 g规格的比例显著低于另外3组,而≥6.00 g规格的比例显著高于另外3组(P<0.05)。结果表明,中华绒螯蟹亲本规格对其后代的养殖性能存在影响,大规格河蟹亲本子一代在扣蟹生产阶段生长速度快、养殖效果好,因此建议在生产上选择大规格亲本的后代用于扣蟹养殖。

Effects of broodstock size on juvenile culture performance of Chinese mitten crab Eriocheir sinensis

To explore the influence of broodstock size on juvenile culture performance of Chinese mitten crab(Eriocheir sinensis),this study compared the average body weight,weight gain rate(WGR),specific growth rate(SGR),survival and final yield of juvenile E.sinensis produced by broodstock with different sizes(SizeⅠ:female 90~110 g,male 140~160 g;SizeⅡ:female 115~135 g,male 160~180 g;SizeⅢ:female 140~160 g,male 220~240 g;SizeⅣ:female 190~210 g,male 290~310 g).The results showed that:(1)No significant difference were observed in average body weight,survival rate and weight gain during the pea-sized juvenile rearing stage(P>0.05);(2)During the pea-sized juvenile and coin-sized juvenile culture stage,growth performance of crabs showed an increasing trend with broodstock size increasing,and the average body weight of crabs in the SizeⅠgroup were significantly lower than the SizeⅣgroup from August to October(P<0.05);(3)In terms of culture effect,the final body weight and yield of crabs also showed an increasing trend with broodstock size increasing,and the crabs in the SizeⅣgroup had significantly higher final body weight than the SizeⅠgroup;(4)As for the size distribution of juvenile crabs,SizeⅣgroup had significantly lower percentage of crabs in the range of 2.00~3.99 g and significantly higher percentage of crabs in the range of≥6.00 g,when comparing to other three groups.In conclusion,broodstock size had an oppositive effect on culture performance of juvenile E.sinensis,which showed an increasing tread with broodstock size increasing.Therefore,juvenile crabs produced by large broodstock could be optimal for culture and promotion.