In the quest to find sustainable alternatives to antibiotics in aquaculture, a team of researchers led by Xiaoyuan Ge from the Chinese Academy of Tropical Agricultural Sciences has made a significant breakthrough. Their study, published in the journal *Animal Nutrition*, highlights the potential of a novel probiotic strain, Bacillus tequilensis Bt-CO, to enhance disease resistance and intestinal health in tilapia.
The research team isolated Bt-CO from coral in a tropical marine environment and evaluated its potential as an antibiotic alternative through a series of in vitro and in vivo trials. The in vivo trials involved feeding tilapia with diets supplemented with different concentrations of Bt-CO. After a four-week feeding period, the fish were challenged with Aeromonas hydrophila, a common pathogen in aquaculture.
The results were promising. Bt-CO demonstrated strong antagonistic effects against several pathogenic bacteria, including A. hydrophila. It also showed excellent physiological characteristics, such as auto-aggregation, adhesion, and biofilm formation, and exhibited remarkable tolerance to bile and gastrointestinal conditions. Notably, Bt-CO colonized the intestines of tilapia without negatively impacting their growth performance.
“Bt-CO supplementation significantly enhanced the tilapia’s resistance to A. hydrophila infection,” said Ge. “This suggests that Bt-CO has the potential to enhance disease resistance in tilapia, likely by strengthening non-specific immunity and improving intestinal health and microecology.”
The study also found that Bt-CO supplementation modulated inflammatory responses by inhibiting pro-inflammatory cytokines and promoting anti-inflammatory cytokines. It also enhanced the expressions of intestinal barrier-related factors, thereby improving intestinal health. Microbiome analysis indicated that Bt-CO supplementation increased the diversity of gut microbiota, promoting beneficial microorganisms while suppressing pathogenic ones.
The commercial implications of this research are substantial. As the aquaculture industry seeks to reduce its reliance on antibiotics, probiotics like Bt-CO offer a promising alternative. By enhancing disease resistance and intestinal health, Bt-CO can potentially improve the overall health and welfare of aquatic organisms, leading to increased productivity and profitability for farmers.
This research could shape future developments in the field by encouraging further exploration of probiotics as antibiotic alternatives. As Ge noted, “Our findings provide a basis for the development of Bt-CO as a novel probiotic for use in aquaculture. However, further research is needed to fully understand its mechanisms of action and optimize its use in different aquaculture systems.”
With the global aquaculture market projected to reach $242.7 billion by 2027, the demand for sustainable and effective feed additives is on the rise. Bt-CO, with its proven benefits, could be a game-changer in the industry. As the research team continues to delve into the potential of this probiotic, the future of aquaculture looks increasingly promising.