Author(s): Claver ZEA BI UE, Issa Nahoua Ouattara and Siaka Berte

Abstract: This study was conducted to evaluate the effects of stocking density on the survival, growth and feeding parameters of larvae of the Brazil strain of Nile tilapia, Oreochromis niloticus in breeding environments. Larvae of initial average weight 0.010 ± 0.002g and initial average total length 8.70 ± 0.83 mm were loaded at densities of 500, 1000, 1500, 2000, 2500 and 3000 larvae / m² called D1, D2, D3, D4, D5 and D6 respectively. The fish were all fed a commercial food (48% protein) distributed manually at a frequency of 6 meals per day. A rationing rate of 40, 30, 25 and 20% of the biomass was applied during the first, second, third and fourth weeks of feeding respectively. Growth controls on samples were used to determine the impact of stocking density on zootechnical parameters. The results show that the final average weight, daily growth and specific growth rate were inversely proportional to the increase in stocking density. However, the densities D1, D2, D3 and D4 do not differ (ANOVA; p > 0.05) from each other, but they are significantly higher (ANOVA; pË‚ 0.05) than the other two densities (D5 and D6). Similarly, survival decreases with increasing density and the low values of this parameter were obtained at the highest loading densities, 83.11% at 2500 larvae / m² and 80.87% at 3000 larvae / m². In contrast to the first two parameters, the feed conversion rate is correlated with the increase in stocking density. These results show that for an improvement in fry production, a stocking density of 2000 larvae / m² can be applied in a happa installed in an earth pond.

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