Document Type : Primary Research paper
To study the effect of cellulolytic gut bacteria as a feed supplement on growth performance and nutrient digestibility of Asian seabass (Lates calcarifer), a 42 days experiment was done. Group I was fed on control diet (diet A), Group II, III and IV were fed with diet B (Bacillus subtilis), C (Bacillus licheniformis), and D (B. subtilis and B. licheniformis in 1:1 ratio) respectively. Higher (P<0.05) weight gain percent (248.75 %), specific growth rate (4.80) and apparent fiber digestibility were observed in group IV. Maximum (P<0.05) survivability (86.67 %), PER and apparent protein digestibility were significantly (P<0.05) higher and FCR (1.24) was significantly (P<0.05) lower in animals of group III. Total microbial population and cellulolytic bacterial population in the gut of juvenile seabass of group IV was significantly (P<0.05) higher than other groups. Amylolytic bacterial population was in the same range of group III and IV but they were significantly (P<0.05) higher than other two groups. Digestive cellulase enzyme activity was significantly (P<0.05) higher in group IV, digestive amylase and protease was in the same range of group III and IV. So, these two cellulolytic gut bacteria B. licheniformis and B. subtilis showed beneficial effect on seabass as feed supplement.