Guava Leaf Additives Boost Shrimp Growth and Immunity, Offering Sustainable Alternative to Antibiotics

Bangladeshi Researchers Identify Guava Leaves as an Effective, Eco-Friendly Feed Additive for Shrimp Aquaculture

A study published in Aquaculture International (2025) by researchers from the University of Chittagong and Noakhali Science and Technology University has demonstrated that tropical guava (Psidium guajava) leaves can significantly enhance growth, feed efficiency, and immune response in black tiger shrimp (Penaeus monodon).

Over a 49-day feeding trial, shrimp were fed diets containing 1%, 2.5%, or 5% leaf powders from papaya (Carica papaya), guava, and sweet potato (Ipomoea batatas), alongside a basal control diet. The research aimed to identify plant-based feed additives that can replace antibiotics in shrimp aquaculture, addressing the global challenge of antimicrobial resistance.

Key Findings

Highest growth and efficiency: Shrimp fed 5% guava leaf powder reached a final average weight of 4.43 g with a feed conversion ratio (FCR) of 0.89 — outperforming papaya and sweet potato diets.
Improved immunity: Guava 2.5% treatment resulted in the lowest mortality (30%) following Vibrio parahaemolyticus infection and maintained the highest total hemocyte count (~5×10⁷ cells/mL).
Enhanced disease resistance: Shrimp in the guava-fed group exhibited delayed mortality onset compared to control and other treatments, confirming immunostimulatory properties.
Sustainable and safe: No adverse effects were observed on water quality or shrimp health parameters across treatments.

Scientific Insights

Guava leaves were found to contain high carbohydrate and bioactive compound levels, including polyphenols and flavonoids known for antimicrobial and antioxidant effects. These compounds likely enhanced shrimp immunity and nutrient utilization efficiency.

In contrast, papaya leaves—with higher protein and papain enzyme content—supported moderate growth and survival benefits, while sweet potato leaves showed limited effects. The combination of improved growth, reduced bacterial infection, and environmental safety positions guava leaf powder as a practical replacement for synthetic antibiotics in shrimp farming.

Conclusion

The researchers concluded that 2.5–5% guava leaf inclusion in shrimp feed offers a cost-effective, natural, and sustainable alternative to antibiotics in aquaculture. This innovation could reduce chemical dependency, lower production costs, and promote eco-friendly shrimp farming across tropical regions.

They also emphasized the need for further research on the bioavailability of plant-derived compounds and long-term effects on shrimp physiology.

Reference

Nusrat, N., Mutsuddy, A., AftabUddin, S., Khan, M. A. A., & Siddique, M. A. M. (2025). Functional plant-based feed additives for shrimp: evaluating the role of phytochemicals from tropical leaves on growth, feed efficiency, and disease resistance in P. monodon. Aquaculture International, 33(6), 586. https://doi.org/10.1007/s10499-025-02253-9