The effect of dietary lipid and lecithin levels on the growth, survival, feeding efficiency, production and carcass composition of post‐larvalPenaeus monodonFabricius

摘要

Abstract.Eight semi‐purified diets were formulated to investigate the effects of dietary lipid and lecithin levels on the performance and carcass composition of post‐larvalPenaeus monodonFabricius.Supplementary soyabean lecithin levels from 0 to 9 and total dietary lipid (cod liver oil:soyabean oil at a ratio of 3:1) levels from 3·5 to 12·5 at 3 increments were tested in diets that were isonitrogenous and isoenergetic. The diets were fed for 50 days to triplicate groups of post‐larvalP. monodonheld in a laboratory marine recirculated water system.Despite poor overall performance due to the purified dietary ingredients, the absence of basal lipids and/or lecithin was found to result in the poorest performance. Optimum production was obtained with a diet containing 3 basal lipid and 3 lecithin at a total lipid level of 6·5. The addition of dietary lecithin (particulariy at 46·63 of the total lipid) at up to 3 in terms of growth, feeding efficiency and production or 6 in terms of survival significantly (P<0·05) increased shrimp production. Lecithin was therefore probably acting as a growth, survival and/or phago‐stimulant inP. monodon.The total lipid requirements are consistent with those reported by other workers for penaeid shrimp, and are probably a result of the requirement for essential fatty acids, the stimulant properties of lecithin and the calorigenic effects of high dietary