Effects of putative dietary probiotics from the gut of milkfish ( Chanos chanos ) on the growth performance and intestinal enzymatic activities of juvenile Nile tilapia ( Oreochromis niloticus )

Abstract

Enzymes synthesized by the gut microbiome are recognized as vital for assisting host metabolism. This study was conducted to screen and identify bacterial isolates with enzyme-producing abilities from the intestine of milkfish Chanos chanos.Overall, 114 isolates were collected, of which 58% showed clear zones indicating various enzyme activities via plate-based assays. Specifically, 65 isolates were amylolytic, 1 isolate was cellulolytic, and 18 isolates exhibited both activities. The two most promising isolates-CC8 and CC27-were further subjected to spectrophotometric enzyme assays to determine their amylase, cellulase and protease activities. Results showed that amylase, cellulase and protease activities (6.00 ± 0.01, 0.52 ± 0.02 and 18.62 ± 0.16 U mg −1 protein, respectively) were higher in CC8 than in CC27. Using 16S rRNA gene sequencing, the isolates were putatively identified as Vibrio sp. and Bacillus cereus respectively. At a suspension (mL) to feed (g) ratio of 3:25, dietary supplementation of putative probiotics was carried out to evaluate the growth performance, survival and enzymatic activities of juvenile Nile tilapia Oreochromis niloticus. Results revealed that probiotic-supplemented fish exhibited better growth performance-final average body weight, weight gain, specific growth rate and feed conversion ratio-along with increased intestinal enzymatic activities compared with the control (p < 0.05). Survival rates ranged from 80% to 90% and were statistically similar in all treatments (p > 0.05). This study concludes that the application of Vibrio sp. CC8 and Bacillus cereus CC27, supplemented either in monostrain or multistrain preparation, can promote growth and enzymatic activities in juvenile Nile tilapia.

Enterobacter asburiae E7, a Novel Potential Probiotic, Enhances Resistance to Aeromonas veronii Infection via Stimulating the Immune Response in Common Carp ( Cyprinus carpio )

“…Probiotic diets containing Vibrio sp. CC8 and B. cereus CC27, alone or in combination, could improve growth performance in juvenile Nile tilapia Oreochromis niloticus ( 66 ). In this study, dietary supplementation with E7 had no significant effect on growth and survival of common carp, indicating that it may exert probiotic effects on the host in other ways.…”

Probiotic Bacteria in Gastro-Intestinal Tract of Hybrid Catfish Fed Insect Protein Meal

“…The demand for fish and other aquaculture products is increasing globally and has resulted in advancement in term of fish feed and nutrition, which function as catalysts for the long-term growth of the rapidly increasing aquaculture sector [37]. Probiotic dietary supplements have been shown to improve fish health and nutrition; however, these bacteria are mostly obtained from some terrestrial and warm-blooded hosts which limit their effectiveness in fish [19]. Most probiotics bacteria found in the GIT system of the relevant fish species will colonize more quickly within the main host [37].…”

“…The prevalence and abundance of probiotics in GIT of fish fed with Diet B and C as compared to their absence in the gastrointestinal tract of the fishes fed with Diet A is an indication that insect protein (especially grasshopper protein) is of good and quality feed and can be used to supplement fish meal in feed diet of fishes. The probiotic bacteria presence in the supplementary feed has the capacity to increase the health status as well as growth performance of fish [18,19,37].…”

“…Probiotics have been employed as a disease control method in aquaculture activities particularly those caused by infection of bacteria [16][17][18][19]. Lactic acid bacteria which originate in the GIT of fish are form of probiotic bacteria that are of benefit to fish health through greater nutrient utilization and antimicrobial capabilities [17].…”

“…Lactic acid bacteria which originate in the GIT of fish are form of probiotic bacteria that are of benefit to fish health through greater nutrient utilization and antimicrobial capabilities [17]. Probiotics boost the immune response to pathogenic illnesses in fish [18][19][20]. Various studies have demonstrated that specific probiotic groups have antibacterial action in vitro on rainbow trout [21], common carp [22], Tilapia [23] and other species of freshwater fishes [24,25].…”