中华鲟幼鲟蛋白质营养最适需要量

Optimum protein level of diets for juvenile Acipenser sinensis

为确定中华鲟 (Acipensersinensis)幼鲟最佳生长的饲料蛋白质适宜含量 ,按单因子梯度设计原理 ,设计 5种不同蛋白质水平配方的饲料 ,分别投喂中华鲟幼鲟 ,测定中华鲟幼鲟体重、体成分 ,同时用外源性指示剂 (Cr2 O3)测定饲料中干物质和粗蛋白的表观消化率 ,比较其测定结果。结果表明 ,饲料蛋白质质量分数为 4 4 .18%时 ,中华鲟的生长效果最好 ;以增重率为指标 ,通过直线回归和抛物线回归推算出中华鲟蛋白质需要的适宜质量分数为4 0 .0 0 %～ 4 3 .0 1%。

Five diets were designed with different protein levels. The main protein sources were fishmeal and soybean meal. The juvenile sturgeon Acipenser sinensis, body weight(13.15±0.51)g, were fed three times each day for 35 d to determine their growth and the digestive trial was conducted in the first 14 d. During the experiment the water temperature was 18.5-20.0 ℃. The results indicate that the optimum protein level is 44.18% ; the protein level in diets does not affect that in the muscle obviously, but the gross energy in the sturgeon body increases with the increase of protein level in diets. The results of the digestive trial shows that the digestive rate increases with the increase of diet protein level until protein level at 48.80% and then gets down.The regression analysis shows the optimum protein level for the requirement of the juvenile sturgeon is 40.00%-43.01%.