大豆分离蛋白替代鱼粉对哲罗鱼氨基酸沉积率的影响

Effects of Dietary Fish Meal Replacement by Soybean Protein Isolate on Amino Acids Retention of Taimen Hucho taimen

在水温9.8~16.2℃下,将初始体质量为(6.90±0.04)g饲养在室内220L玻璃钢水族箱中,投喂含40%鱼粉的对照组饲料和以大豆分离蛋白替代25%、37.5%、50%、62.5%、75%、87.5%和100%鱼粉的等氮等能试验饲料,流水饲养56d。每个处理3个重复,每个重复100尾鱼。结果表明,大豆分离蛋白替代鱼粉后,鱼体增重和干物质显著下降(P<0.05),但肌肉氨基酸组成和含量未出现显著变化(P>0.05);全鱼的异亮氨酸沉积率最高,其次是蛋氨酸、赖氨酸和精氨酸。随着大豆分离蛋白替代鱼粉比例的增加,全鱼的氨基酸沉积率显著下降(P<0.05)。饲料中大豆分离蛋白替代鱼粉不改变哲罗鱼肌肉氨基酸组成和含量,但鱼体氨基酸沉积率降低。

A feeding trial was conducted to evaluate the effects of replacing fish meal with soy protein isolate （SPI） on muscle amino acids profile and whole body amino acids retention in taimen Hucho taimen. Juvenile taimen with an initial body weight of （6.90 ＋ 0.04） g was randomly divided into a 220 L glass fiber reinforced plastic tank and fed diet containing 40% fish meal as control and isoenergetic and isonitrogenous test diets in which SPI was used to replace 25%, 37.5%, 50%, 62.5%, 75%, 87.5% and 100% fish meal with triplication for 56 d. No significant difference in muscular amino acid profile was observed between control group and the test groups （P 〉 0.05 ）. The juveniles fed the test diets had the maximal isoleucine retention, followed by methionine and lysine and arginine in the whole body. Whole body amino acids retention was found to be decreased significantly with increasing SPI level in diets （P 〈 0.05 ）. It is concluded that fish meal replacement by high SPI could not result in any change in muscle amino acids profile, though whole body amino acids retention was decreased with increase in dietary SPI.