国产鱼粉饲料中添加卵黄抗体、丁酸钠和枯草芽孢杆菌对中华鳖生长和摄食偏好的影响

为探究国产鱼粉配合添加剂完全替代进口鱼粉对中华鳖(Trionyx sinensis)生长和摄食偏好的影响,本次实验共设6组软颗粒饲料,分别为进口鱼粉组(67%,IFM),34%国产鱼粉+32%进口鱼粉组(DFM+IFM),67%国产鱼粉组(DFM),67%国产鱼粉组基础上分别添加0.2%卵黄抗体组(DFM-Y)、0.05%丁酸钠(DFM-S)组和0.05%枯草芽孢杆菌组(Bacillus subtilis,DFM-B),饲养中华鳖稚鳖60 d,并分别于第15、30和60天计算相对增重率和成活率。同时,在6种软颗粒料中分别添加100 mg/kg的La_2O_3、Dy_2O_3、Sm_2O_3、Nd_2O_3、Yb_2O_3和Y_2O_3等稀土元素,等量混合投喂后,结合饲料和粪便中的稀土元素含量,考察中华鳖稚鳖对不同饲料的摄食偏好。结果表明,国产鱼粉替代进口鱼粉不影响中华鳖的成活率;饲料中添加枯草芽孢杆菌较DFM组可全程显著提高中华鳖生长,在30 d时较进口鱼粉无显著性差异,卵黄抗体和丁酸钠在前15 d的促生长效果明显;与国产鱼粉和进口鱼粉相比,二者混合后更易提高稚鳖食欲,在全国产鱼粉饲料中添加卵黄抗体、丁酸钠和枯草芽孢杆菌均不会对稚鳖产生促摄食作用;稚鳖对饲料的初始摄食偏好与生长无对应关系,说明摄食不是影响生长的决定因素。

Effect of egg yolk antibody, sodium butyrate and Bacillus subtilis supplementation in domestic fish meal based feed on growth and feeding preference of China soft-shelled turtle

In order to understand the effect of domestic fish meal with exogenous additives replacing the imported fish meal on China soft-shelled turtle (Trionyx sinensis), six groups of soft pellet feeds were designed and formulated with 67% of imported fish meal group(IFM), 34% of domestic fishmeal +32% imported fish meal group (DFM+IFM), 67% of domestic fish meal group (DFM), 67% of domestic fishmeal based group added 0.2% yolk antibody Group (DFM-Y), 0.05% sodium butyrate (DFM-S) group and 0.05% Bacillus subtilis group, (DFM-B), respectively. Relative weight gain rate and survival rate of Chinese soft shelled turtle(Trionyx sinensis) were calculated at 15 d, 30 d and 60d respectively. Meanwhile, in feeding behavior test, the above feeds were individually marked with one of the rare earth oxides (La₂O₃,Dy₂O₃,Sm₂O₃,Nd₂O₃,Yb₂O₃ and Y₂O₃) at 100 mg/kg, and the feeding preference was measured by the concentration of rare earth elements in feces and in the feed determined with inductively coupled plasma atomic emission spectrometry. Results showed that, 6 different diets did not affect the survival rate of Chinese soft shelled turtle; the growth of the turtle fed with the diet containing Bacillus subtilis could be significantly better than DFM group in 60-day feeding period, even not significantly different for IFM group in 30-day feeding period, while with yolk antibody and sodium butyrate enhancing growth performance only in the early feeding stage(15 d) of the juvenile soft-shelled turtle; feed containing mixture of domestic fish meal and imported fish meal was easier to attract juvenile soft-shelled turtle ingestion. There was no improved feeding effect of egg yolk antibodies, sodium butyrate and Bacillus subtilis in domestic fish meal. There was also no corresponding relationship between initial feeding preference and the growth of juvenile turtle, illustrating the feed ingestion was not the determinant for growth.