# Functional Feed for Tilapia: Exploring the Benefits of Aspalathus linearis Tea Extract

## TL;DR

This study shows that adding rooibos tea extract to tilapia larvae diets improves growth and feed efficiency, offering a sustainable aquaculture solution.

## Contribution

The study demonstrates that both fermented and green rooibos extract improve tilapia larval growth and provide genoprotective benefits.

## Key findings

- Rooibos extract diets significantly improved larval growth and feed conversion ratios compared to the control.
- Green rooibos extract showed genoprotective effects, likely due to its phenolic compounds.
- Improved growth is attributed to enhanced palatability, gut health, and nutrient absorption, not macronutrient content.

## Abstract

This study investigated the application of rooibos (Aspalathus linearis) tea extract as a sustainable feed additive for Mozambique tilapia larvae over an eight-week feeding experiment. Diets fortified with 30% fermented and green rooibos extract significantly enhanced larval growth compared to the control group. While the control showed a higher condition factor, the growth efficiency with rooibos extracts was substantial. The findings demonstrate that rooibos tea extract, in both forms, can significantly improve tilapia growth and feed efficiency, presenting it as a promising, cost-effective, and sustainable ingredient for aquafeed for tilapia farming. These findings offer a viable strategy to boost tilapia farming productivity, promoting efficient resource utilization and sustainable aquatic protein production.

To address the growing global demand for aquatic protein and the need for sustainable aquaculture, this study explored Aspalathus linearis tea extract as a novel feed additive for Oreochromis mossambicus larvae. Over an eight-week feeding trial, the efficacy of diets supplemented with 30% fermented or green rooibos extract was assessed against a control. Both fermented and green rooibos treatments significantly (p < 0.05) enhanced larval growth, evidenced by improved weight gain and feed conversion ratios (fermented: 1.50 ± 0.25; green: 1.41 ± 0.07). Notably, A. linearis extracts also demonstrated genoprotective potential, as indicated by a marked reduction in micronucleus frequency, most likely attributed to their abundant phenolic compounds. These findings demonstrate that rooibos extract, especially the green variety, can improve growth performance and feed utilization, and also provide genoprotective benefits. The superior outcomes in growth and feed conversion are likely due to the bioactive phenolic compounds, which may enhance palatability, gut health, and nutrient absorption, rather than macronutrient content. This positions rooibos extract as a promising natural functional additive for aquafeed, offering a sustainable strategy to enhance tilapia farming productivity and resource utilization. However, further research is necessary to uncover specific molecular mechanisms, conduct in-depth analyses of gut health and immune responses, and evaluate effects on product quality to facilitate its sustainable and effective integration into aquaculture practices, thereby contributing to both fish health and food security.