三种蛋白源部分替代鱼粉对军曹鱼幼鱼生长和体成分的影响

配制5种等氮、等能的饲料,D1组以全鱼粉作为蛋白源,D2、D3组分别用脱脂豆粕替代10%和20%鱼粉,D4组以啤酒酵母粉替代10%鱼粉,D5组以玉米蛋白粉替代10%鱼粉,投喂体质量30～38g的幼鱼5周,研究3种蛋白源替代饲料中的鱼粉蛋白对大规格军曹鱼幼鱼生长和体成分的影响。试验结果表明,各组存活率差异不显著(P0.05);D3组体质量、质量增加率、饲料转化率、蛋白质效率和特定生长率均显著低于D1组(P0.05),而其他各组无显著差异(P0.05)。D3组全鱼粗脂肪含量显著低于D1、D5组(P0.05),肌肉灰分含量则显著高于其他组(P0.05);其他各组全鱼和肌肉常规营养成分无显著差异(P0.05)。D3组肝体指数显著低于其他组(P0.05),各组的脏体指数、肝脏脂肪含量和肥满度均无显著差异(P0.05)。试验结果提示,3种蛋白均可替代饲料中10%的鱼粉蛋白而不产生显著影响,但替代比例达到20%,就可能对大规格幼鱼的生长、饲料利用、体成分和健康产生不良影响。

Effects of Partial Replacement of Fish Meal by Three Types of Protein Sources on Growth Performance and Approximate Compositions of Juvenile Cobia ( Rach ycentron canadum )

Five isonitrogenous and isocaloric diets were prepared by the dietary fish meal(D1),and the fish meal replaced by defatted soybean meal for 10%(D2) and 20%(D3),by corn gluten meal for 10%(D4),and by beer yeast meal for 10%(D5),and fed juvenile cobia(Rachycentron canadum)(with body weight of 30~38 g) for 35 days to investigate the effects of replacing fish meal in formulated diet on growth and approximate compositions.There was no significant difference in survival rate between the treatment groups and the control group(P>0.05).There were significantly lower final body weight,weight gain,food conversion efficiency,protein efficiency ratio and specific growth rate in D3 than those in D1(P<0.05),without significant difference between other groups(P>0.05).The juvenile cobia in D3 had significantly lower crude fat content in muscles than the fish in D1 and D5 did(P<0.05),whereas significantly higher ash content than other groups did(P<0.05).The hepatosomatic indexes were significantly lower in the juvenile cobia in D3 group than in other groups(P<0.05).There were no significant differences in visceral index,hepatopancreas rude fat content and Fulton’s condition factor in all treatment groups(P>0.05).The results showed that defatted soybean meal,corn gluten meal and beer yeast meal can replaced 10% fish meal for diet and did not caused significant effects.But if the replacement proportion reached 20% for fishmeal,there were significant negative effects on growth,food consumption rate,approximate compositions and health in bigger juvenile cobia.