水产复合酶在不同蛋白水平下对鲫鱼生长性能及表观消化率的影响

Effects of compound enzymes on growth performance and apparent digestibility of Gibel carp at different protein levels

试验研究了在不同蛋白水平条件下水产复合酶对鲫鱼(3.47±0.05)g生长性能的影响。试验共分5个组,T0组为对照组,饲喂基础日粮(蛋白含量为33%左右);T1、T2组在对照组基础上分别添加200、500g/t的复合酶;T3、T4组在对照组基础上降低1.5个百分的蛋白再分别添加200、500g/t的复合酶。每组设4个重复,每个重复30尾鱼,进行90 d的循环水养殖试验。结果显示,与对照组(T0)相比,直接加酶的T1、T2组的相对增重率分别提高了4.82%、6.71%;特定生长率分别提高了2.51%、3.23%;饵料系数分别降低了1.06%、3.19%;且500g/t的添加量组(T2)较200g/t组(T1)有改善;但三组之间差异不显著(P>0.05)。降低1.5个百分点蛋白添加酶制剂的T3组生长性能有下降趋势,相对增重率和特定生长率均小于对照组(T0组),饵料系数大于对照组,但也无显著性差异(P>0.05),仅与直接加500g/t酶的T2组差异显著。T4组生长性能与对照组相当。与对照组(T0)相比,直接加酶和降低蛋白加酶均有提高鲫鱼干物质、粗蛋白、能量和磷表观消化率的趋势。其中,T4组的干物质表观消化率显著高于对照组(P<0.05);所有加酶组的粗蛋白表观消化率均显著高于对照组,分别提高了2.54、2.99、1.87和3.21个百分点;T1组的能量消化率低于对照组,其它组高于对照组,但均无显著性差异(P>0.05);T2组的磷表观消化率显著高于对照组。同时,随复合酶添加量的增加,各营养物质的表观消化率有改善的趋势。

The present study was conducted to performance in the diet with different protein estimate the effect of dietary enzyme cocktail on growth levels to Gibel carp, Carassius auratus gibelio. Experi- mental diets were divided into 5 groups：the control diet（designated TO） was prepared with 33% dietary protein.Based on the TO diet,T1 and T2 diets were supplemented with 200 mg/kg and 500 mg/kg test- ed enzymes, T3 and T4 diets were prepared with 31.5% dietary protein, along with 200 mg/kg and 500 mg/kg tested enzymes.Each diet was fed to four replicate groups of 30 tilapia[mean initial weight = 3.47＋0.05 g; mean ＋ SD）] for 90 d. Results showed that when compared with the control group,T1 and T2 group had a higher weight gain rate,specific growth rate and a lower feed conversion rate, whereas there was no difference between the control group and T4 group.However, this phenomenon was not consistent with T3 group.Also,the supplementation of exogenous enzyme improved the apparent digestibility coefficient of dry matter, crude protein,energy and phosphorus.