Effects of stocking density on growth, production and farming profitability of African catfish Clarias gariepinus (Burchell, 1822) fed chicken viscera-diet in earthen ponds

Abstract

The effects of stocking density on growth, production and farming profitability of Clarias gariepinus fed practical chicken viscera-diets was studied in earthen ponds for 90 days. Fish (initial weight: 13.1 ± 0.2 g) were hand-fed to apparent satiation twice daily with diet (43 % crude protein, 20 kJ g-1) formulated by mixing 30 % of chicken viscera with locally available ingredients (diet CVM30), and distributed to three triplicates group of fish, each group assigning one of the three densities: 5, 7 and 10 fish m-2. Survival rate was not affected by stocking density (p>0.05). Final weight, specific growth rate and weight gain increased until density of 7 fish m-2, and decreased at 10 fish m-2 (p<0.05), the optimal values attaining 260.7 g, 3.32 % day-1, 1890.3 %, respectively. The AFCR is as lower in all stocking density, values ranging from 0.96 to 1.20. Yield and annual production are density-dependent, values ranging from 100.5 to 209.9 kg are-1 and from 407.7 to 851.1 kg are-1year-1. The profitability index was high, amounting 2.08 to 2.25 in all stocking density (p˂0.05). The highest profitability index was obtained at density of 7 fish m-2, whereas identical value was obtained with 5 and 10 fish m-2densities. Based on the growth performances and taking into account the lack of capital to invest in rural areas, the study suggests rearing C. gariepinus at the density of 7 fish m-2 with diets containing chicken viscera meal at up 30%, for optimal fish production and profit in Benin rural areas.