Valorization of Benthic Macroinvertebrates Produced from Pig Dung in Clarias gariepinus Fries Feeding

Fish feeding is one of the main factors hindering the development of fish farming in developing countries. The objective of this study was to determine the optimal artificial feed ration to be fed as a supplement to macroinvertebrate fed fry for semi-intensive production of Clarias gariepinus. To this end, the survival and growth performance of Clarias gariepinus fries fed with macroinvertebrates produced from pig dung and artificial feed were compared to those of fry fed with dry feed only. Fries with an initial weight of 0.52 ± 0.15g were distributed in the 15 buckets with a density of 0.6 ind.L-1 and grouped into four (04) treatments (T1, T2, T3 and T4) and a control (T0); they were fed for 05 weeks. Fries reared in T1, T2, T3 and T4 were fed with 75%, 50%, 25% and 0% dry feed respectively, while those in T0 were fed with 100% dry feed. All four treatments contain macroinvertebrates produced in mass. The physicochemical parameters of the water, the survival and growth parameters of the fry were assessed. The results showed that the physicochemical parameters of the water were within the recommended standards for the culture of the majority of aquatic species The average final weight and specific growth rate of the fries were highest in T0 (11.95 ± 0.06 g and 8.96 ± 0.014 %.d-1), followed by T1 (10.50 ± 0.8 g and 8.58 ± 0.2 %.d-1) and T2 (10.16 ± 0.50 g and 8.49 ± 0.14 %.d-1). They are very low in T4 (01.35 ± 0.11 g and 2.72 ± 0.23 %.d-1). The specific growth rate and survival rate of T1, T2 and T0 were not significantly different (p > 0.05). T1 and T2 will therefore reduce the amount of artificial feed to be distributed; however, the optimal rate was 50% (T2). It is therefore possible to reduce the cost of fish products in a semi-intensive system.