ABSTRACT
Aquatic probiotics are considered as a safe additive, to provide health benefits to the cultured fish by enhancing growth and immunity, improving feed utilisation rate, increasing digestive enzyme activity, maintaining water quality, controlling diseases, modulating microbial colonisation in the intestine and predigestion of anti-nutritional factors present in the feed. Morphological and biochemical characterisation was performed in order to confirm the probiotic characteristics of those Bacillus sp. according to Bergey’s Manual of Determinative Bacteriology. The study followed a completely randomised design, with one control and four treatments, receiving four different Bacillus sp. at same concentration each of which were triplicated. The lipase activity of GIT samples were determined according to Cherry and Crandell using a stabilised emulsion of olive oil. The present study noticed a significant increase in digestive enzyme activity of probiotic supplemented diet fed groups. In addition to this, good appetite behaviour was observed in all the treatment groups, except control group.
