EFFECTS OF DIETARY PHOSPHORUS LEVEL AND INORGANIC SOURCE ON SURVIVAL AND GROWTH OF PENAEUS-VANNAMEI POSTLARVAE IN ZERO-WATER EXCHANGE CULTURE TANKS

Zero-water exchange culture tanks were stocked with Penaeus vannamei p ostlarvae to compare the effects of (i) three dietary phosphorus level s: 0.4, 0.8 and 1.2 % and (ii) three dietary inorganic phosphorus sour ces: CaHPO4, Na2HPO4 and NaH2PO4, on postlarvae biological performance , and total reactive phosphorus accumulation in the water (TRPAW). Die tary Ca:P ratio was maintained within a 1:1 to 1:2 ratio. Postlarvae s urvival was high and not significantly different among treatments. Pos tlarvae growth was not significantly different, regardless of dietary phosphorus level. TRPAW was significantly higher with increasing level of dietary phosphorus. Dietary inorganic phosphorus source did not ha ve a significant effect on postlarvae growth. No significant differenc es were found on TRPAW between diets with Na2HPO4 and NaH2PO4 suppleme ntation at equal dietary phosphorus level. TRPAW was significantly low er with CaHPO4 than with Na2HPO4 or NaH2PO4 supplementation at equal d ietary phosphorus level. Environmental quality of culture water may be greatly modified through nutritional strategies without negatively af fecting shrimp biological performance. (C) Ifremer-Elsevier, Paris.