点带石斑鱼幼鱼配合饲料的适宜能量蛋白比

以鱼粉和酪蛋白为蛋白源,添加鱼油、豆油、α-马铃薯淀粉、纤维素以及适量的维生素和矿物质配制成实验饲料,蛋白质质量分数设置41%、47%、53%3个水平,能量设置12 561、14 655、16 748 kJ/kg 3个水平,饲养点带石斑鱼幼鱼59 d后,以增重率、蛋白质效率、饲料系数为评价指标,分析不同能量蛋白比的饲料对点带石斑鱼体内消化酶活性的影响。结果表明:当能量蛋白比分别为31.30、33.50、32.26 kJ/g时,点带石斑鱼增重率、蛋白质效率达到极大值,饲料系数达到极小值;能量蛋白比在31.62～35.54 kJ/g范围内,胃、肠道的蛋白酶、淀粉酶、脂肪酶活性较强。点带石斑鱼幼鱼配合饲料中合适的能量蛋白比为31.62～33.50 kJ/g。

Optimum Energy to Dietary Protein Ratio for Juvenile Grouper (Epinephlus coioides)

The optimum ratio of dietary energy to protein for the grouper(Epinephlus coioides) fingerlings were determined using practical diets in a 3 × 3 factorial experiments.Three energy levels of 12 561,14 655,16 748 kJ/kg at each protein level and three protein levels of 41%,47% and 53% were utilized.The experimental fish(initial body weight,24.68±1.20 g) were reared in floating net cages(150 cm×100 cm×100 cm) for 59 days.Based on calculating weight gain,feed conversion rate and protein efficiency rate,and analyzing the effects of different energy-protein ratio in the diet on the activities of digestive enzymes for grouper,the experimental results indicated that when the ratio of dietary energy to protein reached 31.30,33.50 and 32.26 kJ/g,the growth rate and protein efficiency rate reached their maxima and the feed conversion rate arrived at its minima respectively.And when the ratio of dietary energy to protein is between 31.62 and 35.54 kJ/g,the activities of protease,amylase and lipase in the stomach and intestine were strong.So the optimum ratio of dietary energy to protein for the grouper fingerlings was between 31.62 and 33.50 kJ/g.