南方鲇的营养学研究：Ⅲ．饲料脂肪对蛋白质的节约效应

于１９９７年１０月至１２月对南方鲇（Silurus meridionalis)(初始体重：３０－４４g)进行人工配合饲料的喂养实验。实验以白鱼粉和 玉米油作蛋白质和脂肪源，共配制６种不同蛋白质／脂肪比的饲料，其蛋白质（Ｐ）和脂肪（Ｌ）的含是分别为４３％Ｐ／１５％Ｌ，４７％Ｐ／１５％Ｌ，５１％Ｐ／１６％Ｌ，５０％Ｐ／８％Ｌ，５４％Ｐ／８％Ｌ，５８％Ｐ／８％Ｌ。实验每饲料水平设４个重复，采用室内循环水养殖系统，在２７．５℃下以饱足日粮水平喂养６周。实验结果表明：供以高脂肪低蛋白质饲料组鱼体的特殊生长率（ＳＧＲ）和饲料转化率（ＦＣＥ）与低脂肪高蛋白饲料的无显著差异，而前者喂养的实验鱼的蛋白质效率（ＰＥＲ）显著大于后者，因此，南方鲇饲料脂肪对蛋白质有明显的节约效应。

THE UNTRITION OF SILURUS MERIDIONALIS:

From October to December, 1997, the growth experiment of the southern sheatfish, Silurus meridionalis, was conducted with initial weight 30—44 g. The fish were fed with artificial formulated diets of different ratios of protein (P) to lipid (L), i.e. 43%P/15%L, 47%P/15%L, 51%P/16%L, 50%P/8%L, 54%P/8%L, 58%P/8%L, in the aquariums with recirculated water system. At each of the diets 4 groups of the Southern Sheatfish (10 fish in each group) were fed at ad libitum ration level for 6 weeks at 27.5℃. Significant difference was not found in specific growth rate (SGR) and food conversion efficiency (FCE) between the fish at the higher lipid and lower protein level of diets and those at the lower lipid and higher protein level. But protein efficiency ratio (PER) in the former was significantly higher than in the later. With the dietary lipid content increased from 8% to 15%, the optimum dietary protein level estimated for the fish declined from 54% to 43%. It was suggested that dietary lipid had significant protein-sparing effect on this fish.