【作者】 余连渭；

【导师】 朱邦科；

【作者基本信息】 华中农业大学 ， 水产养殖， 2003， 硕士

【摘要】 配制十七种半精制饲料，通过六周养殖实验，对黄颡鱼幼鱼(均重2.0g)的蛋白质和能量需要进行了研究。每种饲料设三个平行试验组，每日投喂二次，日投喂率4％～5％。具体研究结果如下： 1．设定总能为20.01MJ／kg，采用八种蛋白质含量梯度(20％～5％)饲料，以增重率为指标，通过折线模型，确定了黄颡鱼幼鱼饲料的适宜蛋白质含量为37.49％，维持体重的蛋白质含量为10.37％，折合蛋白质需要量1.50g～1.81g／100g鱼·d，维持需要量0.41g～0.52g／100g鱼·d。饲料蛋白质含量过低(20％)时，黄颡鱼增重率、成活率和鱼体粗脂肪含量均显著低于其它组(P＜0.05)；增重率随饲料蛋白质含量增加而增加，在蛋白质含量50％时最高，但当蛋白质含量增加到55％时，黄颡鱼增重率呈下降趋势，且55％组的鱼体粗脂肪含量显著高于其它组(P＜0.05)。蛋白质含量过低(20％)和过高(55％)，蛋白质沉积率都显著低于其它组(P＜0.05)。 2．设定四个总能水平(18.87MJ／kg、20.01MJ／kg、21.39MJ／kg、22.81MJ／kg)和三个蛋白质含量(35％、40％、45％)的十二种饲料，以总能和蛋白质含量为因子，以增重率、蛋白质沉积率和能量保留率为指标，通过二元二次回归方程确定黄颡鱼幼鱼饲料的总能适宜值为19.89MJ／kg～20.06MJ／kg，适宜能量蛋白比为46.35kJ／g～52.93kJ／g。 3．黄颡鱼对蛋白质需要量的适宜值与饲料总能水平有关。总能较低(18.87MJ／kg)时，则饲料蛋白质含量从35％提高至40％以上时，黄颡鱼的增重率、蛋白质沉积率和能量保留率等指标显著提高，饲料系数显著降低(P＜0.05)；总能较高(21.39MJ／kg、22.81MJ／kg)时，蛋白质含量增加，黄颡鱼的增重率、蛋白质沉积率和能量保留率呈下降趋势，饲料系数呈上升趋势，表明饲料总能提高，黄颡鱼对蛋白质需要量降低。 4．黄颡鱼饲料总能的适宜值与饲料蛋白质含量有关。在蛋白含量为35％时，总能21.39MJ／kg组的黄颡鱼增重率和饲料转化效率最好；在蛋白含量为40％以上时，总能18.87MJ／kg组的黄颡鱼增重率和饲料转化效率最好。 5.饲料总能过高(22.slMJ瓜g)时，黄颗鱼的增重率、成活率和饲料转化效率均显著低于其它能量水平组(P<0.05)。表明总能过高的饲料不适宜于黄颗鱼生长和饲料利用。 6.饲料总能和蛋白质含量对鱼的生长和饲料转化有极显著的交互作用(P<0.01)。低能低蛋白含量饲料(总能1 8.87MJ瓜g、蛋白质含量35%)和高能高蛋白含量饲料(总能21·39MJ瓜g和22·81MJ瓜g、蛋白质含量45%)下，黄颗鱼的增重率和饲料转化效率显著低于适宜总能(20.01MJ瓜g)和适宜蛋白含量(40%)饲料(P<0.05)。 7.总能从18.87MJ/kg提高至20.01MJ瓜g以上时，鱼体水份和粗蛋白含量显著减少(P<0.05);粗脂肪含量随总能提高呈现先增后降趋势，在总能ZI.39MJ/kg组最高;当总能增加至22.81MJ/kg时，粗脂肪含量较ZI.39MJ瓜g组显著降低 (P<0 .05)。更多还原

【Abstract】 Seventeen semi-purified diets were formulated to estimate the protein and energy requirements of juvenile yellow catfish (initial average weight 2.0g) by a 6-week feeding trial. Each diet was fed in triplicate to groups of yellow catfish at 4%~5% of body weight, twice a day. The main results were summarized as follows:1. Eight isoenergetic diets (20.01MJ gross energy/kg) with protein contents ranging from 20% to 55% at an increment of 5% were used. Based on weight gain rate (WGR), a broken-line model fitted by least squares showed that the dietary protein requirement for the optimum growth of juvenile yellow catfish was 37.49%, and 10.37% for the weight maintenance, that is 1.50g -1.8 Ig protein requirement per lOOg body weight per day for the optimum growth, 0.41g~0.52g/100g-d for maintenance. When dietary protein content was as low as 20%, WGR and body crude lipid contents were significantly lower. But when protein level increased to 55%, WGR tend to decrease, body crude lipid content was significantly higher (P<0.05). Whether the dietary protein content was low (20%) or high (55%), protein deposit rate (PDR) were significantly lower (PO.05).2. Using the second-order polynomial regression analysis, the optimum gross energy and the optimum energy to protein ratio in diets for juvenile yellow catfish were estimated to be 19.89MJ/kg~20.06MJ/kg and 46.35kJ/g~52.93kJ/g based on WGR, PDR and energy retention rate (ERR) of the juveniles fed twelve diets with four energy levels (18.87MJ/kg, 20.01MJ/kg, 21.39MJ/kg and 22.81MJ/kg) and three protein contents (35%, 40%, 45%).3. The optimum dietary protein requirement was related to dietary gross energy (DGE). When DGE decreased from 20.01MJ/kg to 18.87MJ/kg, the dietary protein content should increase to 40% for improved growth of juvenile yellow catfish. Withthe diets containing high gross energy levels (21.39MJ/kg, 22.81MJ/kg), WGR, PDR and ERR of juvenile decrease and FCE increase as dietary protein contents increased, indicating low protein requirement of juvenile yellow catfish with diets of high energy levels.4. The optimum DGE was related to dietary protein content as well. When the dietary protein content was 35%, the optimum DGE for growth and feed utilization was 21.39MJ/kg. While the dietary protein content increased to 40% or more, the optimum DGE decreased to 18.87MJ/kg.5. When DGE was as high as 22.81MJ/kg, WGR, PDR and ERR were significantly lower, FCE was significantly higher (P<0.05) than other energy levels, indicating that diets with too high energy level would inhibit the growth and feed utilization of juvenile yellow catfish.6. DGE interacted with dietary protein content significantly (P<0.01) on growth and feed utilization of juvenile yellow catfish. Diet with low energy level (18.87MJ/kg) and low protein content (35%) resulted in poor growth of juvenile catfish and bad feed utilization, so did diets with high energy levels (21.39MJ/kg, 22.81MJ/kg) and high protein content (45%).7. Increased DGE from 18.87MJ/kg to 20.01MJ/kg or higher resulted in significant (P<0.05) decrease in body moisture and crude protein content, and body crude lipid content, increase at first and then decrease as DGE increased. The body crude lipid content was highest when DGE was 21.39MJ/kg.更多还原