Effect of fertilization on production of Nile tilapia reared in earthen ponds: III) effect of nontraditional organic fertilizer on the fish yield of mixed-sex Nile tilapia (oreochromis niloticus) [electronic resource].

Includes references.

This experiment was designed to determine the optimal fertilizing rate of Abis organic fertilizer in mixed sex Nile tilapia reared In earthen ponds. Six ponds (200 m²) were assigned for 3 treatments: 50, 75 and 100 g fertilizer/m²/wk. Fish in this experiment were fed a restricted level of 20.93% protein diet for fourteen weeks and 17.4% protein diet for another four weeks. The experiment lasted for 126 days. Water quality parameters were monitored weekly during the experimental period. Tilapia growth rate, specific growth rate, gross yield of initial stock and net yield of initial stock were significantly different among treatments, with the highest at fertilizing rate of 75 g / m² wk⁻¹, and the lowest at fertilizing rate of 100 g / m² wk⁻¹ . The highest recruitment was produced at the highest fertilizing rate (100g / m² wk⁻¹ ). Highest net return was achieved at the fertilizing rate of 75g / m² wk⁻¹ while the lowest was at the fertilizing rate 100 g / m² wk⁻¹. The effect of the treatments on water quality parameters was discussed.

Summary in Arabic.

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