Influence of varying dietary protein content at three lipid concentrations on growth characteristics of juvenile swordtails (Xiphophorus helleri Heckel 1848)

摘要

Three protein levels (30 percent, 38 percent and 45 percent) at three different dietary lipid concentrations (6 percent, 8 percent and 12 percent) were used to formulate nine different diets that were fed for 60 days to 6-8 weeks old juvenile swordtails (Xiphophorus helleri). It would appear that a diet of at least 45 percent protein at a 6 percent lipid concentration is needed for the best specific growth rate (1.27 percent per day) and feed conversion ratio (2.50) at this specific growth phase inX. helleri. No 'protein sparing effect' was found when lipid concentration was increased at lower protein levels.