纯化饲料、活饵料及其混合投喂对三疣梭子蟹幼蟹生长性能、肝胰腺指数和生化组成的影响

Effects of purified diet,fresh foods and mixed diets on the survival,growth performance and biochemical composition of juvenile swimming crab,Portunus trituberculatus

采用单个体养殖实验和生化分析技术,研究了纯化饲料(A组)、活饵料(章鱼和缢蛏,B组)和混合投喂(纯化饲料和活饵料有规律地交替使用,C组)对三疣梭子蟹幼蟹(初体重0.5 g左右)成活、生长性能、肝胰腺指数(HSI)和生化组成的影响。结果表明:(1)3组幼蟹的成活率并无显著差异,均在70%～80%之间;(2)A组和B组幼蟹的增重率、蜕壳周期、特定增长率和饲料系数无显著差异,C组幼蟹的第二次蜕壳周期和饲料系数显著低于其它两组,其特定增长率显著高于其它两组;(3)3种投喂方式的饵料对幼蟹的肝胰腺指数及其蛋白和脂肪含量影响显著,A组幼蟹肝胰腺指数及其脂肪含量显著高于其它两组,但蛋白含量显著低于其它两组;(4)就脂肪酸组成而言,A组肝胰腺和躯体中的饱和脂肪酸和单不饱和脂肪酸均高于其它两组,多不饱和脂肪酸和高度不饱和脂肪酸显著低于其它两组。因此,研制的纯化饲料可以使三疣梭子蟹幼蟹获得较好的生长性能,为进一步开展梭子蟹幼蟹营养需求研究奠定了良好的基础。

By the individual culture technique and biochemical analysis,this study is to investigate the effects of purified diet（group A）,fresh foods（Octopus variabilis and Sinonovacula constricta,group B） and mixed diets（purified diets and fresh foods,group C） on the survival,growth performance and biochemical composition of juvenile swimming crab Portunus trituberculatus（initial mean wet weight was 0.5g）.The results are as follows：（1） The survival of juvenile swimming crab ranged from 70% to 80%,and no significant effects caused by survival were observed among three groups.（2） There were no significant differences in the WGR（weight gain ratio）,molting period,SGR（specific growth rate） and FCR（feed conversion ratio） of juvenile swimming crab between group A and B.The second molting cycle of group C was significantly shorter and FCR was significantly lower than the other two groups,however,SGR of group C was significantly higher than the group A and group B.（3） Each diet showed a significant effect on the Hepatosomatic Index（HSI）,and its protein and lipid contents.The HSI and the lipid content of group A were significantly higher,however,the protein content was significantly lower than the other two groups.（4） With regard to the fatty acid composition,the saturated fatty acids and mono-unsaturated fatty acids of hepatopancreas and body from group A were significantly higher than the other two groups,and the poly-unsaturated fatty acids and highly unsaturated fatty acids were significantly lower than the other two groups.In conclusion,juvenile swimming crab fed our purified diets could achieve good growth performance,which lays a solid foundation for the further study on the nutrition requirments for this crab species.