In the quest to reduce antibiotic use in aquaculture, a groundbreaking study led by Wonsuk Choi from the Feeds and Foods Nutrition Research Center at Pukyong National University in Busan, South Korea, has shown promising results. The research, published in Frontiers in Nutrition, explores the potential of fish-derived probiotic bacteria as a sustainable alternative to antibiotics in olive flounder diets.
The study, which involved 450 juvenile olive flounder, compared the effects of three probiotic bacteria—Bacillus subtilis WB60, B. subtilis SJ10, and Enterococcus faecium SH30—against a control diet and two antibiotic treatments, amoxicillin and oxytetracycline. The results were striking. Fish fed diets supplemented with B. subtilis WB60 (Pro-A) showed significantly higher weight gain, specific growth rate, and feed efficiency compared to those fed the control, oxytetracycline, and amoxicillin diets. “The probiotic bacteria not only enhanced growth performance but also bolstered the fish’s immune response,” Choi explained. “This dual benefit is crucial for sustainable aquaculture practices.”
The study also revealed that the probiotic diets led to improved intestinal health, with longer villi lengths observed in the fish fed probiotic-supplemented diets. This morphological improvement suggests better nutrient absorption and overall gut health. Moreover, the probiotic diets significantly increased lysozyme and myeloperoxidase activities, key indicators of innate immunity. “The enhanced immune response is a game-changer,” Choi noted. “It means that fish are better equipped to fight off diseases, reducing the need for antibiotics.”
The cumulative survival rates of fish fed probiotic diets were significantly higher after a challenge test with the pathogenic bacterium Edwardsiella tarda. This finding underscores the potential of probiotics to improve disease resistance in aquaculture. The study also highlighted the role of probiotics in modulating gene expression related to inflammation and immune response, further supporting their potential as a sustainable alternative to antibiotics.
The implications of this research are far-reaching. As the aquaculture industry continues to grow, the demand for sustainable and efficient feed additives is increasing. Probiotics offer a promising solution, not only for improving fish health and growth but also for reducing the environmental impact of antibiotic use. “This research paves the way for a more sustainable future in aquaculture,” Choi said. “By replacing antibiotics with probiotics, we can enhance fish health, reduce environmental pollution, and ensure the long-term viability of the industry.”
The findings published in Frontiers in Nutrition, also known as Frontiers in Nutrition, provide a robust foundation for further research and commercial applications. As the industry moves towards more sustainable practices, the integration of probiotics into fish diets could become a standard practice, benefiting both the environment and the bottom line of aquaculture operations.