The effect of indigenous probiotics on egg hatchability and larval viability of Clarias gariepinus

Abstract

The effect of a mixture of four indigenous bacterial genera composed of Bacillus, Pseudomonas, Acinetobacter and Flavobacterium on egg hatchability and larval viability of Clarias gariepinus was investigated. The fertilized eggs were distributed into glass Petri dishes (100 mm diameter) containing 50 ml of water at graded level of mixed indigenous probiotics ranging from 0-108 cells/ml. The incubation time increased from 17 hours at 0 cfu/ml to 22 hours at 108 cfu/ml. The mean hatching rate increased from 8.70% at 0 cfu/ml to 53.85% at 108 cfu/ml. The highest larval survival of 71.43% recorded at 108 cfu/ml where the highest hatching rate was observed, was significantly higher than the larval survival rate observed at the other concentrations. All yolk sac larvae at 0 and 101 cfu/ml died before the end of yolk sac period. These results imply that the incubation time, hatching rate and larval survival of Clarias gariepinus increased with increase in bacterial load of water up to 108 cells/ml, the highest dose employed. Further investigations are needed to establish the optimal and threshold doses.