植酸酶对凡纳滨对虾生长性能和体成分的影响

在凡纳滨对虾饲料中添加不同量微生物植酸酶(0,500,1000,2000 U/kg),观察虾的存活率、增重率、饲料系数及虾体和虾壳成分,研究饲料中添加植酸酶对凡纳滨对虾生长性能的影响。结果表明:饲养8周后,饲料中添加500~2000 U/kg植酸酶对凡纳滨对虾增重率、存活率和饲料利用无显著影响(P>0.05);植酸酶添加各组与对照组虾体的水分、粗蛋白、脂肪、灰分、总钙和总磷含量差异不显著;虾壳中粗灰分和钙含量在500和1000 U/kg组显著高于对照组和2000 U/kg组(P<0.05),虾壳磷含量在各饲料组间差异不显著。血清磷浓度在对照组和2000 U/kg组显著高于500 U/kg组(P<0.05),血清钙浓度在组间差异不显著,血清碱性磷酸酶活性以对照组最高,显著高于500和1000 U/kg组。结果说明,在特定试验条件下,饲料中添加植酸酶对凡纳滨对虾幼虾的虾壳和血清成分有显著影响(P<0.05),对幼虾生长性能影响不显著(P>0.05)。

Effects of Dietary Phytase Supplement on Growth Performance and Body Composition of Juvenile Shrimp Penaeus vannamei

Different levels of microorganic phytase(0,500,1000,2000 U/kg) were added to the diet of Penaeus vannamei to investigate the effects of dietary phyatse supplement on growth performance and body composition.Survival percentage,weight gain,feed conversion ratio and the compositions of whole body,exoskeleton and serum were evaluated.The results showed that the dietary phytase supplement of 500～2000 U /kg had no significant effects on weight gain and survival percent age in Penaeus vannamei(P>0.05).There were no significant differences in moisture,crude protein,crud fat,ash,calcium and phosphorus contents of whole body among groups.Ash and calcium contents of exoskeleton in shrimp fed diet with 500 and 1000 U/kg phyatse supplement were significantly higher than those in control and 2000 U/kg group(P<0.05).Phosphorus contents in exoskeleton were not significantly different among groups.Phosphorus concentrations in serum in the groups of basal diet and 2000 U/kg diet were higher than that in the groups of 500 U/kg diet(P<0.05).Serum calcium concentrations were not significantly different among groups.Serum alkaline phosphatase activity was the highest in the control group and significantly higher than the 500 U/kg and 1000 U/kg groups.The results suggested that dietary phytase supplement had significant effects on the compositions of carapace and serum(P<0.05) but not on growth performance(P>0.05) in juvenile Penaeus vannamei under the present experimental conditions.