本试验旨在探讨饲料蛋白质水平对幼虾阶段和养成阶段凡纳滨对虾生长性能、全虾和肌肉常规营养成分及血清生化指标的影响，以确定凡纳滨对虾幼虾阶段和养成阶段的蛋白质需要量。以鱼粉、小麦蛋白粉、酪蛋白和明胶为主要蛋白质源配制蛋白质水平分别为29.31%、33.19%、37.11%、41.45%、45.58%、49.03%的6种饲料。试验1（幼虾阶段养殖试验）和试验2（养成阶段养殖试验）分别选用720尾初始体重为（0.52±0.01） g和540尾初始体重为（7.93±0.03） g的凡纳滨对虾作为试验动物，均随机分为6组，每组3个重复（桶），试验1每桶放养40尾，试验2每桶放养30尾。试验1和试验2的养殖期分别为56和42 d。试验1结果表明：随着饲料蛋白质水平的升高，对虾的增重率（WGR）和特定生长率（SGR）均先显著上升（P<0.05）而后趋于稳定（P>0.05），而饲料系数（FCR）呈相反的变化趋势；饲料蛋白质水平为37.11%~49.03%时，蛋白质效率（PER）随饲料蛋白质水平的升高显著下降（P<0.05）；饲料蛋白质水平对对虾的成活率（SR）、肝体指数（HSI）未产生显著影响（P>0.05）；29.31%组对虾的肥满度（CF）显著低于其他各组（P<0.05）。各组对虾全虾、肌肉干物质及全虾粗蛋白质含量均无显著差异（P>0.05）；37.11%组全虾粗脂肪含量显著高于45.58%和49.03%组（P<0.05）；29.31%和41.45%组全虾粗灰分含量显著高于33.19%和37.11%组（P<0.05）；肌肉粗蛋白质含量在41.45%组达到最高值，并显著高于29.31%和49.03%组（P<0.05）；29.31%组肌肉粗脂肪含量显著低于除37.11%组外的其他各组（P<0.05）；33.19%组肌肉粗灰分含量显著高于37.11%、41.45%和49.03%组（P<0.05）。血清总蛋白（TP）含量及天冬氨酸转氨酶（AST）活性各组间无显著差异（P>0.05）；33.19%组血清总胆固醇（TC）含量显著高于其他各组（P<0.05）；41.45%和49.03%组血清甘油三酯（TG）含量显著高于29.31%和33.19%组（P<0.05）；45.58%组血清超氧化物歧化酶（SOD）活性显著高于其他各组（P<0.05）；41.45%和45.58%组血清酚氧化酶（PO）活性显著低于其他各组（P<0.05）；血清丙氨酸转移酶（ALT）活性最低值出现在37.11%组，并显著低于其他各组（P<0.05）。试验2结果表明：随着饲料蛋白质水平的升高，对虾SR、WGR、SGR、FCR及HSI的变化趋势同试验1结果；对虾的PER随饲料蛋白质水平的升高持续下降，29.31%和33.19%组显著高于41.15%、45.58%和49.03%组（P<0.05）；各组对虾的CF无显著差异（P>0.05）。全虾干物质、粗脂肪、粗灰分以及肌肉粗脂肪、粗灰分含量各组间均无显著差异（P>0.05）；29.31%组全虾粗蛋白质含量显著低于其他各组（P<0.05）；45.58%和49.03%组肌肉干物质含量显著高于29.31%和41.45%组（P<0.05）；45.58%和49.03%组肌肉粗蛋白质含量显著高于29.31%、33.19%和37.11%组（P<0.05）。45.58%组血清碱性磷酸酶（AKP）活性显著高 于29.31%和33.19%组（P<0.05）；血清SOD活性在45.58%组达到最高值，并显著高于其他 各组（P<0.05）；血清PO活性在37.11%组达到最低值，并显著低于29.31%、33.19%和49.03%组（P<0.05）；血清ALT活性各组间没有显著差异（P>0.05）；血清AST活性在37.11%组达到最高值，并显著高于29.31%、33.19%和45.58%组（P<0.05）。以SGR为评价指标，经折线模型拟合回归方程后得出，凡纳滨对虾幼虾阶段和养成阶段的蛋白质需要量分别为38.6%和36.8%。

This study was conducted to investigate the effects of dietary protein level on the growth performance, whole body and muscle common nutritional components and serum biochemical indices of Pacific white shrimp (Litopenaeus vannamei) during juvenile shrimp and grow up stages, in order to determine the protein requirements of Pacific white shrimp during juvenile shrimp and grow up stages. Fish meal, wheat gluten meal, casein and gelatin as the main protein sources were used to formulate six experimental diets at various protein levels (29.31%, 33.19%, 37.11%, 41.45%, 45.58% and 49.03%, respectively). A total of 720 shrimp with an initial body weight of (0.52±0.01) g and 540 shrimp with an initial body weight of (7.93±0.03) g were used as experimental animals in test 1 (feeding test for juvenile shrimp stage) and test 2 (feeding test for grow up stage), and were randomly assigned to 6 groups with 3 replicates per group and 40 (test 1) or 30 (test 2) shrimp per replicate (bucket), respectively. The test 1 and test 2 lasted for 56 and 42 days, respectively. The results of the test 1 showed as follows: with the dietary protein level increasing, the weight gain rate (WGR) and specific growth rate (SGR) were firstly significantly increased (P<0.05) and then tended to be stable (P>0.05), while the feed conversion ratio (FCR) had an opposite trend; when dietary protein levels were 37.11% to 49.03%, the protein efficiency ratio (PER) was significantly decreased (P<0.05) with the dietary protein level increasing; there were no significant differences in survival rate (SR) and hepatosomatic index (HSI) among all groups (P>0.05); the condition factor (CF) in 29.31% group was significantly lower than that in other groups (P<0.05). There were no significant differences in the contents of whole body and muscle dry matter and whole body crude protein among all groups (P>0.05); the content of whole body crude lipid in 37.11% group was significantly higher than that in 45.58% and 49.03% groups (P<0.05); the content of whole body ash in 29.31% and 41.45% groups was significantly higher than that in 33.19% and 37.11% groups (P<0.05); the content of muscle crude protein in 41.45% group was the highest, and significantly higher than that in 29.31% and 49.03% groups (P<0.05); the content of muscle crude lipid in 29.31% group was significantly lower than that in other groups except 37.11% group (P<0.05); the content of muscle ash in 33.19% group was significantly higher than that in 37.11%, 41.45% and 49.03% groups (P<0.05). There were no significant differences in serum total protein (TP) content and aspartate aminotransferase (AST) activity among all groups (P>0.05); serum total cholesterol (TC) content in 33.19% group was significantly higher than that in other groups (P<0.05); serum triglyceride (TG) content in 41.45% and 49.03% groups was significantly higher than that in 29.31% and 33.19% groups (P<0.05); serum superoxide dismutase (SOD) activity in 45.58% group was significantly higher than that in other groups (P<0.05); serum phenol oxidase (PO) activity in 41.45% and 45.58% groups was significantly lower than that in other groups (P<0.05); serum alanine aminotransferase (ALT) activity in 37.11% group was the lowest, and significantly lower than that in other groups (P<0.05). The results of the test 2 showed as follows: with the dietary protein level increasing, the trends of SR, WGR, SGR, FCR and HSI were consistent with the results of test 1; the PER was continuously decreased with the dietary protein level increasing, and that in 29.31% and 33.19% groups was significantly higher than that in 41.15%, 45.58% and 49.03% groups (P<0.05); there was no significant difference in CF among all groups (P>0.05). There were no significant differences in the contents of whole body dry matter, crude lipid and ash and muscle crude lipid and ash among all groups (P>0.05); the content of whole body crude protein in 29.31% group was significantly lower than that in other groups (P<0.05); the content of muscle dry matter in 45.58% and 49.03% group was significantly higher than that in 29.31% and 41.45% groups (P<0.05); the content of muscle crude protein in 45.58% and 49.03% groups was significantly higher than that in 29.31%, 33.19% and 37.11% groups (P<0.05). Serum alkaline phosphatase (AKP) activity in 45.58% group was significantly higher than that in 29.31% and 33.19% groups (P<0.05); serum SOD activity in 45.58% group was the highest, and significantly higher than that in other groups (P<0.05); serum PO activity in 37.11% group was the lowest, and significantly lower than that in 29.31%, 33.19% and 49.03% groups (P<0.05); there was no significant difference in serum ALT activity among all groups (P>0.05); serum AST activity in 37.11% group was the highest, and significantly higher than that in 29.31%, 33.19% and 45.58% groups (P<0.05). With the SGR as an evaluation index, regression equations which fitted by broken-line models show that the optimum dietary protein requirements of Pacific white shrimp during juvenile shrimp and grow up stages are determined to be 38.6% and 36.8%, respectively.