Effects of exogenous enzyme supplementation in diets on growth and feed utilization in African catfish, Clarias gariepinus

Abstract

The effects of various supplemental exogenous enzyme on the growth performance in African catfish Clarias gariepinus (initial mean weight 46.32±0.29 g) were examined for 12 weeks feeding trial. A multi enzyme complex (containing fungal xylanase, βJ-glucanase, pentosonase, β3-amilase, fungal β3-glucanase, hemicellulase, pectinase, cellulase, cellubiase), was included at the level of 0.0 (control group), 0.25, 0.5 and 0.75 g enzyme complex kg-1 diet in four test diets. Each of the four experimental diets was randomly assigned to triplicate groups of fish and accidentally stocked into 100 L aquaria at a density of 10 fish per aquarium. After 90 days of rearing, the survival rate was ranged from 86.67-93.33% and there was no statistical difference between experimental and control groups. Growth rate significantly increased in fish fed with enzyme complex supplemented diets in comparison with the control groups (p<0.001). Specific growth rate was ranged from 1.09±0.03 (control group) to 1.23±0.01 (0.75 g kg-1 enzyme complex supplemented group). The best specific growth rate was observed at the group receiving 0.75 g kg-1 enzyme complex group. Also, food conversion ratio, protein efficiency ratio and apparent net protein utilization were significantly higher in all enzyme complex groups than that with control (p<0.01). The highest value of protein content (21.75%) was observed at 0.75 g kg-1 enzyme complex group. The results suggested that enzyme supplementation can significantly improve growth performance and feed utilization in African catfish. © Medwell Journals, 2010.