Influence of partial and total static culture water withdrawal on water quality, growth and feed utilisation of African catfish (Clarias gariepinus Burchell, 1822), Juveniles

Abstract

A sixty day experiment was conducted to investigate the effect of partial and total removal of rearing water on growth performance and feed utilisation of Clarias gariepinus juveniles. C. gariepinus of average weight 10g were stocked at 5kg/m3 and hand fed with 45% Crude Protein (CP) diet twice daily at 5% body weight. The experiment had two treatments, one with partial culture water withdrawal (PWW) and the other, involving total withdrawal of static culture water (TWW). Apart from Alkalinity and Hardness which were both lower in the partial water withdrawal system, there was no significant difference in water quality parameters between the two treatments. All selected water quality parameters were within acceptable range for fish culture. The mean weight gain by fish was relatively higher in PWW compared to TWW with values 36.03±7.12 g and 27.43±0.63 g respectively. The specific growth rate was also higher in PWW (3.73±0.30%/day) compared to TWW (3.37±0.43%/day). Total feed consumed also followed the same trend with 553.57±27.77 g and 459±32.91 g in PWW and TWW respectively. A lower food conversion ratio of 1.54±0.24 was however recorded in PWW compared to 1.67±0.08 in TWW system. These results demonstrated that fish cultured in partial water withdrawal performed relatively better both in terms of growth and feed utilisation.