Growth response and profitability of the African catfish (Clarias gariepinus Burchell, 1882) cultured at different stocking densities

Abstract

The growth response and profitability of Clarias gariepinus fingerlings held at five different stocking densities were studied with the aim of establishing the optimum stocking level that gives the fastest growth and the highest profit. The fingerlings(Mean weight 2.55 + 0.23g) were cultured at five different densities (2, 5, 10, 15, and 20 fish/m2 or 68, 170, 340, 510, and 680 fish per treatment respectively) in earthen ponds of 3.21m x 5.54m x 0.78m at the Department of Wildlife and Fisheries Management Research Farm, University of Ibadan for a period of 12 weeks. Harvest weights at the end of 12 weeks were, 6.43, 12.3, 19.8, 26.7 and 30.0 kg per treatment, respectively. Mean fish weight per treatment was highest at the lowest density of 2 fish/m2 (P<0.05). Specific growth rate (SGR) and percent protein intake (% PI) decreased with increasing stocking density of fish. Survival percentage (SP) was independent of stocking density but total production however, increased with increasing stocking density. Mean Weight Gain was positive and correlated significantly with Feed intake (r = 0.37); SGR (r = 0.22); PI (r = 0.37); Weight change (r = 0.64); pH (r = 0.19) and Dissolved oxygen (r = 0.11). It however, correlated negatively with Feed conversion ratio (r = - 0.03); Temperature (r = - 0.11) and Alkalinity (r = - 0.19)