Abstract Full Text:PDF Recommended articles Mail to Author How to Cite

¹ Cairo University, Department of Animal Production, Fish Nutrition Laboratory (FNL), 12316, Giza, Egypt
² Aquaculture Department, Fish Resources College, Suez Canal University, Egypt
³ Ministry of Agriculture and Fisheries Wealth, Directorate of Fisheries Research, Aquaculture Centre, Fish Nutrition and Physiology laboratory, Sultanate of Oman DOI : 10.4194/1303-2712-v13_1_02 Viewed : 4205 - Downloaded : 4424 An experiment was conducted to evaluate if phosphorus (P) supplement is required in Nile tilapia Oreochromis niloticus broodstock diet under hapa-in-pond system. Seven isonitrogenous (33% crude protein), isocaloric (4400 kcal kg-1) diets were formulated. A corn-soybean meal based diet, deficient in P, was used as the basal diet. Three levels of meat and bone meal (MBM), and mono-sodium phosphate (MSP) were substituted for corn-starch in the basal diet to produce experimental diets containing 0.56, 0.67, or 0.78% P. Males and females with mean body weights of (270±1.52 g) and (250±1.17 g), respectively, were stocked at a density of 4 fish m^-1, (8 fish hapa^-1) with a male: female ratio of 1:3. Irrespective of P source, it was observed that, increasing P level significantly (P≤0.05) increased broodstock fecundity. Spawning performance and egg weight were not significantly affected by dietary P source. However, dietary MBM increased the absolute fecundity and total egg production (P≥0.05) compared to the MSP diets. While, broodstock fed MSP diets showed the highest egg weight. This result revealed that Nile tilapia broodfish reared in the green water under hapa-in-pond system require a source of dietary P for optimum spawning performance. Keywords : Phosphorus, Nile Tilapia Broodstock, Hapa-in Pond, Reproductive Performance