翘嘴红鲌幼鱼最适蛋白需求量的研究

Studies on the Optimum Protein Requirement of Fingerling Topmouth Culter

以鱼粉为蛋白源,配制5个不同蛋白水平的等能、等氨基酸平衡模式的半纯合饲料,饲养翘嘴红鱼白幼鱼2个月,探讨蛋白质的最适需要量。结果表明:饲料蛋白质水平对鱼的增重率、蛋白效率均具有显著的影响(P<0 05),质量分数为42 76%的饲料组鱼体增重显著高于32 58%、37 64%饲料组(P<0 05),但与47 53%和52 49%饲料组没有显著差异(P>0 05)。蛋白效率在各组之间的差异与增重率在各组之间的变化相类似。翘嘴红鱼白幼鱼最大增重的适宜蛋白水平为43 19%～48 68%,蛋白效率最大的饲料蛋白质质量分数为42 50%,饲料蛋白质量分数为37 64%、42 76%、47 53%3个饲料组的蛋白效率差异不显著(P>0 05)。在本试验条件下,翘嘴红鱼白幼鱼的蛋白质最适需要量为42 50%～43 19%。

A series of growth experiments was conducted to study the optimum dietary protein level of topmouth culter(Erythroculter ilishaeformis Bleeker) for a 2-month feeding trial .Fish meal was used as the sole dietary protein source to formulate isoenergetic and the same EAA balance experimental semi-purified diets at five protein levels (32.56%,37.64%,42.76%,47.53% and 52.49%) in 5% increments. The results showed that with the increase of dietary protein level, weight gain (WG) and protein efficiency ratio (PER)were significantly influenced by dietary protein levels (P<0.05). Weight gain of the fish fed the 42.76% protein diets was significantly higher than that of the fish fed 32.58%,37.64% protein diets (P<0.05),but not significantly different from that of the fish fed the 47.53% and 52.49% protein diets (P>0.05) .The changes of PER among different tested groups followed the similar pattern as that of WG. The dietary protein level that yielded maximum growth was 43.19%～48.68% based on linear regression and parabolic curve model estimation of weight gain. The optimum dietary protein level for supporting maximum feed utilization was 42.50% for topmouth culter(Erythroculter ilishaeformis Bleeker). Dietary protein requirement was estimated at approximately 42.50%～43.19% for maximum growth and maximum feed utilization under the experimental condition.