Evaluation of potential applications of dietary probiotic (Bacillus licheniformis SB3086): Effect on growth, digestive enzyme activity, hematological, biochemical, and immune response of Tilapia (Oreochromis mossambicus)

The present study was designed to evaluate the dietary effect of dietary supplementation of Bacillus licheniformis on growth, hematological and immune parameters of Oreochromis mossambicus fingerlings. A feeding trial of 8 weeks was carried out, in which fish were fed at a rate of 2% body weight with four experimental diets, including a control diet and three supplemented diets such as, 105, 107 and 109 CFUg-1 respectively. At the termination of feeding experiment, growth related parameters, hematological and immune response of fish were evaluated. Feed conversion ratio (FCR) was significantly decreased, inferring high efficiency in utilizing feed. In similar groups, hematological parameters such as total erythrocyte count, total leukocyte, total serum protein, blood glucose level and hemoglobin count were significantly increased (P<0.05), with higher probiotic concentration. Similarly, digestive enzyme activity of protease, lipase and amylase was also higher in fish fed with increased concentration of probiotic. Diet groups having 109 CFUg-1 of probiotic was observed with elevated immune response, as levels of lysozyme activity, respiratory burst activity and phagocytic activity were significantly higher (P<0.05) in this group as compared to control group. In conclusion, supplementation of diet with Bacillus licheniformis can enhance growth performance, and health status of O. mossambicus.