2种盐度和3种糖源对凡纳滨对虾生长和糖代谢的影响

为研究肌醇对不同盐度 (4和28) 条件下凡纳滨对虾 (Litopenaeus vannamei) 幼虾生长、血清生化指标和非特异性免疫的影响，选取初始体质量为 (0.75±0.03) g的凡纳滨对虾为研究对象，以添加0、100、200、400、800和1 600 mg∙kg⁻¹肌醇的6种等氮等脂饲料持续投喂10 周。结果表明，高盐度对虾终末体质量、增重率、成活率、特定生长率、蛋白质效率、蛋白质净利用率、总胆固醇含量、酸性磷酸酶、碱性磷酸酶、总超氧化物歧化酶和一氧化氮合酶显著高于低盐度 (P<0.05)，饲料系数和水分则相反。饲料系数和总胆固醇含量随饲料中肌醇水平的升高而降低，终末体质量、增重率、成活率、特定生长率、蛋白质效率和蛋白质净利用率则相反，肌醇添加组的肝体比、酸性磷酸酶和碱性磷酸酶活性显著高于对照组 (P<0.05)。综上，饲料中添加肌醇可促进凡纳滨对虾的生长发育，提高其成活率和非特异性免疫力；低盐条件下凡纳滨对虾的生长发育和免疫力受抑制，肌醇水平不低于100 mg∙kg⁻¹能使其生长发育恢复至高盐水平，不低于200 mg∙kg⁻¹可在一定程度上提高其免疫力。

Effects of salinity and pH on ion-transport enzyme activities,survival and growth of Litopenaeus vannamei postlarvae

To study the effects of inositol on the growth, serum biochemical indices, and non-specific immunity of juvenile Litopenaeus vannamei at different salinities (4 and 28), we fed the shrimps of the initial body mass of (0.75±0.00) g with six diets containing 0, 100, 200, 400, 800 and 1 600 mg∙kg⁻¹ inositol for 10 weeks, respectively. The results show that the final body mass, weight gain rate, survival rate, specific growth rate, protein efficiency, net protein utilization, total cholesterol, acid phosphatase, alkaline phosphatase, total superoxide dismutase and nitric oxide synthase were significantly higher at high salinity than at low salinity (P<0.05); while the feed coefficient and moisture were the reverse. The feed coefficient and total cholesterol content decreased with increasing inositol levels in the diet, but the final body mass, weight gain rate, survival rate, specific growth rate, protein efficiency and net protein utilization increased, and the hepatopancreas somatic indices, acid phosphatase and alkaline phosphatase were significantly higher in inositol-added groups than in the control group (P<0.05). In summary, feeding inositol diets are recommended to improve shrimp's growth, survival and immutability; shrimp's growth and immunity are suppressed at low salinity; feeding higher than 100 mg∙kg⁻¹ inositol diets can restore the growth to a high salinity level, and feeding higher than 200 mg∙kg⁻¹ inositol diets can improve shrimp's immunity.