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为了研究军曹鱼-一种极具发展潜力的适合在热带亚热带网箱养殖鱼类的饲料中蛋白质和脂肪的最适含量,进行了两期生长实验。在第Ⅰ期的生长实验中,在以鱼粉为基础饲料中添加酪蛋白代替淀粉,使饲料形成含蛋白36～60％的梯度,7种饲料据估算是等能量的。经过8周的生长实验,投喂含44％、48％和52％蛋白质的几种饲料的稚鱼(实验开始时体重33g)的体重增长及饲料转化率均优于其他几组。多元回归分析结果表明,摄食含44.5％蛋白质的饲料的稚鱼,体重增长率最高,这被认为是最适合于稚鱼生长的饲料蛋白质水平。在第Ⅱ期生长实验中,给稚鱼投喂含脂肪3～18％的7种等氮和等能量的饲料,稚鱼(初始体重41g)的生长率在脂肪含量为3％时最低,随着饲料含脂量的升高,鱼体增重率逐渐升高,然后持平。采用折线回归分析结果表明,当饲料脂肪含量达到5.76％时,鱼的生长达到一个转折点,饲料脂肪含量超过这个转折点至实验的最高浓度18％时,鱼的生长情况变化不大。
Two cohorts of growth experiments were conducted in order to study Cobia, a highly promising protein and fat optimal diet for foraging farmed fish in tropical subtropical cages. In the first growth experiment, casein was added to fishmeal-based diets instead of starch, so that the feed formed a gradient of 36-60% of protein. The seven kinds of feed were estimated to be of equal energy. After 8 weeks of growth, juvenile fish (weighing 33 g at the start of the experiment) fed several diets containing 44%, 48%, and 52% protein gained better weight gain and feed conversion than the other groups. Multivariate regression analysis showed that juvenile fish consuming 44.5% protein had the highest weight gain, which is considered the most suitable feed protein for juvenile growth. In the phase II growth experiment, juveniles were fed with 7 equal nitrogen and other energy feeds containing 3-18% fat. The growth rate of juvenile (initial body weight 41g) was the lowest at 3% Feed fat content increased, the body weight gain gradually increased, and then flat. The result of polyline regression analysis showed that the growth of fish reached a turning point when the feed fat content reached 5.76%. When the feed fat content exceeded this turning point to the experimental maximum concentration of 18%, the growth of fish did not change much.