大规格中华绒螯蟹亲本子代大眼幼体在微山湖地区的池塘扣蟹培育试验

为探究大规格中华绒螯蟹(Eriocheir sinensis)亲本子代大眼幼体在山东微山湖地区的池塘养殖效果,2019年在微山湖扣蟹基地将2种大规格河蟹亲本(规格Ⅰ:雌190~210 g、雄280~300 g;规格Ⅱ:雌240~260 g、雄330~350 g)所产的大眼幼体饲养至扣蟹,并比较各组扣蟹的生长情况、养殖性能、规格分布和经济效益。试验结果:(1)在相同的养殖管理下,规格Ⅰ组扣蟹在8—10月期间的平均规格稍低于规格Ⅱ组,但2组扣蟹的最终规格并无明显差异(P>0.05);(2)两组大眼幼体在扣蟹阶段的最终养殖性能无显著差异,大眼幼体到扣蟹阶段的成活率约为22%,非早熟扣蟹产量约为300 g/m²,饲料系数为2.1,饲料成本约为13元/kg;(3)从非早熟扣蟹的体质量分布看,规格Ⅰ组中体质量在4.00~5.99 g和8.00~9.99 g的比例显著高于规格Ⅱ组,规格Ⅱ组中体质量<4.00 g、6.00~7.99 g和>10.00 g的扣蟹比例高于规格Ⅰ组,2组扣蟹体质量占比最高的均为4.00~5.99 g;(4)就养殖成本而言,规格Ⅱ组购买大眼幼体的费用高于规格Ⅰ组,饲料、苗种、池塘租金和人工费用为4项主要的投入成本,占总投入的80%以上,但规格Ⅱ组扣蟹的销售价格高于规格Ⅰ组,因此其最终利润及投入产出比都高于规格Ⅰ组。试验结果表明,通过科学的养殖管理,微山湖地区开展大规格亲本子一代大眼幼体的扣蟹池塘养殖可以获得较好的养殖效果和经济效益。

Investigation on culture performance of megalopae hatched byarge-sized Chinese mitten crab Eriocheir sinensis broodstock in the Weishan Lake region

To explore the influence of large-sized broodstock on juvenile culture performance of Chinese mitten crab(Eriocheir sinensis)in the Weishan Lake region,this study investigated the average body weight,weight gain rate(WGR),specific growth rate(SGR),survival and final yield of juvenile E.sinensis produced by broodstock with lagre sizes(SizeⅠ:female 190~210 g,male 280~300 g;SizeⅡ:female 240~260 g,male 330~350 g).The results showed that:(1)During the juvenile E.sinensis culture stage,the average body weight of crabs in the Size I group were relatively lower than Size II group from August to October,but no obviouse difference were observed in final average body weight(P>0.05);(2)Juvenile culture performance ware similar among two groups,the whole survival,yield,feed conversion ratio(FCR)and cost were about 22%,300 g/m²,2.1 and 13 RMB/kg,respectively.(3)As for body weight distribution of normal crabs,the final average body weight of crabs in the SizeⅠandⅡgroups both focused in the range of 4.00~5.99 g.In addition,crabs in the SizeⅠgroup had significantly higher percentages in the ranges of 4.00~5.99 g and 8.00~9.99 g,but had significantly lower percentages in the ranges of<4.00 g,6.00~7.99 g and>10.00 g.(4)In terms of culture profits,althouth the cost of megalopae was obviously higher in the SizeⅡgroup,selling price of SizeⅡjuveniles were obviously higher than the Size I group,this contributed to higher profit and input-output ratio of SizeⅡgroup.In conclusion,megalopae produced by large-sized E.sinensis broodstock could achieve preferable culture performance and economic benefits in the Weishan Lake region.