凡纳滨对虾对饲料中钙、磷的营养需求

水温28~31℃,盐度21~24,养殖凡纳滨对虾幼虾,投喂以乳酸钙为钙源、磷酸二氢钠为磷源,在钙添加水平为0%、0.5%、1.0%的条件下,分别添加0%、0.4%、0.8%、1.2%、1.6%的磷配制的15种饲料,探讨凡纳滨对虾饲料中钙、磷的适宜添加量。8周的养殖试验结果显示,饲料钙、磷水平及钙、磷水平的交互作用极显著影响对虾质量增加率、特定生长率、蛋白质效率、饲料系数和存活率(P<0.01)。饲料钙、磷水平极显著影响对虾肌肉粗蛋白、粗脂肪和全虾粗蛋白的含量(P<0.01)。饲料钙、磷水平的交互作用极显著影响全虾粗蛋白和肌肉粗蛋白、粗脂肪的含量(P<0.01)。饲料钙水平极显著影响全虾和虾壳的钙、磷含量及肌肉磷含量(P<0.01),显著影响对虾肌肉钙含量(P<0.05)。饲料磷水平及钙、磷水平的交互作用极显著影响全虾、肌肉、虾壳的钙、磷含量(P<0.01)。饲料钙、磷水平及钙、磷水平的交互作用均不显著影响血清钙离子含量(P>0.05)。在本试验条件下,以特定生长率为判断依据,通过折线模型分析得出,饲料中添加0.5%的钙和0.88%的磷时凡纳滨对虾的特定生长率最高。

Effects of Dietary Calcium and Phosphorus Levels on Growth,Body Composition,Tissue Calcium and Phosphorus Deposition and Serum Biochemical Indices in Pacific White Shrimp Litopenaeus vannamei

Juvenile Pacific white shrimp Litopenaeus vannamei with initial body weight of(4.2±0.15)g were cultured in a 0.30 m^3 glass fiber reinforced plastics barrel and fed diets containing 0%,0.5%and 1.0%of calcium(Ca)prepared by calcium lactate and containing 0%,0.4%,0.8%,1.2%and 1.6%of phosphorus(P)prepared by sodium dihydrogen phosphate at water temperature of 28-31℃and a salinity of 21-24 for 8 weeks to investigate the effects of dietary calcium and phosphorus levels on growth,body composition,tissue calcium and phosphorus deposition and serum biochemical indices in Pacific white shrimp.It was found that dietary Ca,and P levels and the interaction of Ca and P levels significantly affected the weight gain,specific growth rate,protein efficiency,feed conversion ratio and survival rate of the shrimp(P<0.01).The contents of crude protein and crude lipid in muscle and crude protein in whole body of shrimp were significantly affected by dietary Ca and P levels(P<0.01).The interaction of dietary Ca and P levels led to significantly affect the contents of crude protein in whole body and crude protein and crude lipid in muscle(P<0.01).Dietary Ca levels significantly affected the contents of Ca and P in whole body and exoskeleton and P in muscle in the shrimp(P<0.01),and significantly affected the content of Ca in muscle(P<0.05).The dietary P levels and interaction of Ca and P levels significantly affected the content of Ca and P in whole body,muscle and exoskeleton in shrimp(P<0.01).There was no significant effect of Ca and P levels and interaction of dietary Ca and P levels on the content of serum calcium ion(P>0.05).The analysis of break-line model revealed that the maximal specific growth rate was observed in the shrimp fed the diet containing 0.5%Ca and 0.88%P under the conditions of this experiment.