Growth Performance and Proximate Composition of African Catfish (Clarias gariepinus) Cultured in Cages and Pens in Northern Benin Water Reservoirs Exposed to Cotton-field Effluents

The potential use of water reservoirs exposed to cotton-fields effluents in northern Benin was explored for African catfish (Clarias gariepinus) production. A 120-day experiment was conducted to evaluate the rearing performance of C. gariepinus in two culture systems (cage and pen) tested each in two water reservoirs, one located within the cotton basin (Batran) and the other outside (Songhaï). Measured water physico-chemical parameters were within the tolerable limits for C. gariepinus. Survival rates were similar among treatments and above 92%. Water reservoir, culture system and their interaction influenced significantly the final mean body weight (g), specific growth rate (%/day), and condition factor (%). The highest values of these parameters were observed in fish from cages at Batran (701.09±38.82 g, 2.88±0.05, and 0.84±0.00), while the same culture system displayed the lowest values (296.83±19.95 g, 2.16±0.06, and 0.67±0.02), statistically similar to those obtained in pens at Songhaï. Feed utilization parameters were similar between the culture systems. Fish with high mean final body weight contained less water and more ash and gross energy (p<0.05). We recommend cage culture for improved rearing of African Catfish in northern Benin water reservoirs.