南方鲇的营养学研究:饲料的最适蛋白质含量

THE NUTRITION OF SILURUS MERIDIONALIS:OPTIMUM DIETARY PROTEIN LEVEL

设计了 6个不同蛋白质水平 (39.9% ,43.7% ,46.8% ,51 .6% ,55.7% ,59.1 % )的等能饲料 ,采用室内循环水养殖系统 ,在水温为 2 7.5± 0 .2℃的条件下对南方鲇幼鱼进行了 43d的生长实验。结果显示 :随饲料蛋白质含量的升高 ,特殊体重生长率 (SGR)、饲料干物质转化率 (FCEdm)、蛋白质转化率 (FCEp)、能量转化率 (FCEe)和蛋白质效率 (PER)均产生了显著的差异 (P <0 .0 5) ;干物质摄食率 (RLdm)与饲料蛋白质含量负相关 (r=- 0 .62 ,P <0 .0 1 ) ;蛋白质摄食率 (RLp)与饲料蛋白质含量正相关 (r=0 .96,P <0 .0 1 ) ;能量摄食率 (RLe)不受饲料蛋白质含量的影响 (P >0 .0 5)。通过讨论提出南方鲇饲料的最适蛋白质含量为 47%～ 51 %。

A 43-day growth experiment was conducted in a recirculated filtered rearing system to identify the optimum dietary protein level for juveniles of the southern catfish, Silurus meridionalis, at the water temperature of 27.5±0.2℃. White fishmeal was used as the main dietary protein source to formulate isocaloric experimental diets at six protein levels (39.9%,43.7%,46,8%,51.6%,55.7% and 59.1%). The results showed that dietary protein levels influenced significantly the specific growth rate (SGR), feed conversion efficiency (FCE) and protein efficiency ratio (PER) ( P<0.05 ), but the ration level of energy (RL e). was not affected Negative correlation was observed between ration level of dry matter (RL dm ) and dietary protein level (r=-0.62 , P<0.01 ). However . The ration level of protein (RL p) was positively related to dietary protein level (r=0.96, P<0.01 ). It is suggested that the optimum dietary protein level for the catfish should be 47—51%.