凡纳滨对虾幼虾饲料中适宜钙和磷添加水平

Optimum Calcium and Phosphorus Supplemental Levels in Diets for Juvenile Litopenaeus vannamei

本试验旨在研究饲料不同钙、磷添加水平对凡纳滨对虾(Litopenaeus vannamei)幼虾的生长性能、体成分、组织钙和磷水平和血清指标的影响。采用双因素试验设计,在钙添加水平为0、0.50%、1.00%的条件下,分别添加0、0.40%、0.80%、1.20%、1.60%的磷,配制15种不同钙和磷水平的试验饲料。将1 800尾初始重为(0.38±0.01)g的对虾随机分为15组,每组投喂1种试验饲料,每组3重复,每重复40尾虾。养殖8周。结果表明:1)饲料钙添加水平及钙添加水平与磷添加水平的交互作用极显著影响对虾的增重率(WGR)、特定生长率(SGR)、蛋白质效率(PER)和饲料系数(FCR)(P<0.01);饲料磷添加水平极显著影响对虾的WGR、SGR、PER、FCR和存活率(SR)(P<0.01)。2)饲料钙添加水平极显著影响对虾的肌肉粗蛋白质(CP)、粗脂肪(CL)、粗灰分(Ash)的含量(P<0.01),显著影响对虾的全虾CL、Ash的含量(P<0.05);饲料磷添加水平极显著影响对虾全虾CP、CL含量,肌肉CP、CL、Ash含量(P<0.01);饲料钙添加水平与磷添加水平的交互作用极显著影响对虾全虾CL含量,肌肉CP、CL、Ash含量(P<0.01)。3)饲料钙添加水平和磷添加水平及二者的交互作用极显著影响对虾的全虾、肌肉、虾壳的钙和磷水平(P<0.01)。4)饲料钙添加水平极显著影响对虾的血清碱性磷酸酶(ALP)、酚氧化酶(PO)活性,钙离子(Ca2+)含量(P<0.01);饲料磷添加水平极显著的影响对虾血清ALP、PO的活性,胆固醇(CHOL)、甘油三酯(TG)、无机磷(IP)的含量(P<0.01),显著影响对虾血清Ca2+的含量(P<0.05);饲料钙添加水平与磷水平的交互作用极显著影响对虾的血清ALP活性,Ca2+、IP的含量(P<0.01),显著影响对虾血清TG含量(P<0.05)。在本试验条件下,以SGR为判断依据,通过二次回归曲线模型分析得出凡纳滨对虾幼虾饲料中钙和磷的适宜添加水平分别为1.00%和1.26%。

This experiment investigated the effects of different dietary supplemental levels of calcium(Ca)and phosphorus(P)on growth performance,body composition,deposition of Ca and P in tissues and serum indexes of juvenile Litopenaeus vannamei,and find the optimum supplemental levels of Ca and P in diets.Two factors experimental design was used.Three Ca supplemental levels(0,0.50%and 1.00%)and five P supplemental levels(0,0.40%,0.80%,1.20%and 1.60%)were adopted,and there were 15 kinds of diets with different Ca and P levels.A total of 1 800 shrimps with initial weight of(0.38±0.01)g were randomly divided into 15 groups,each group was fed one of experimental diets,each group had 3 replicates,and each replicate had 40 shrimps.An 8-week feeding trial was conducted.The results showed as follows:1)dietary Ca supplemental level and the interaction of Ca and P supplemental levels significantly affected weight gain rate(WGR),specific growth rate(SGR),protein efficiency ratio(PER)and feed conversion rate(FCR)of shrimps(P<0.01);dietary P supplemental level significantly affected WGR,SGR,PER,FCR and survival rate(SR)of shrimps(P<0.01).2)Dietary Ca supplemental level significantly affected contents of crude protein(CP),crude lipid(CL)and ash in muscle(P<0.01),and significantly affected contents of CL and ash in whole body of shrimps(P<0.05);dietary P supplemental level significantly affected contents of CP,CL in muscle,and CP,CL and ash in whole body of shrimps(P<0.01);the interaction between dietary Ca and P supplemental levels significantly affected CL content in whole body and contents of CP,CL and ash in muscle of shrimps(P<0.01).3)Dietary Ca and P supplemental levels and their interaction significantly affected levels of Ca and P in whole body,muscle and exoskeleton of shrimps(P<0.01).4)Dietary Ca supplemental level significantly affected serum activities of alkaline phosphatase(ALP)and phenol oxidase(PO),and the content of calcium ion(Ca 2+)(P<0.01);dietary P supplemental level significantly affected serum activities of ALP and PO,and contents of cholesterol(CHOL),triglyceride(TG)and inorganic phosphorus(IP)(P<0.01),and significantly affected serum Ca 2+content of shrimps(P<0.05);the interaction between dietary Ca and P supplemental levels significantly affected serum ALP activity,Ca 2+and IP contents(P<0.01),and significantly affected serum TG content(P<0.01).Under the condition of the present experiment,according to SGR,through the analysis of quadratic regression curve model,it is concluded that the optimal supplemental levels of Ca and P in diets for juvenile Litopenaeus vannamei are 1.00%and 1.26%,respectively.