Tetraselmis chuii biomass as a potential feed additive to improve survival and oxidative stress status of Pacific white-leg shrimp Litopenaeus vannamei postlarvae

Abstract

Shrimp is an important traded fishery commodity. When subjected to stress, shrimp usually suffers from oxidative stress, which leads to cell injury, senescence, and death. To maintain shrimp good health, performance and production, antioxidant and immune systems are important. Natural antioxidants found in microalgae may be used to increase the cell protection against oxidative damage, being a promising alternative to the carcinogenic synthetic antioxidants. In this study, <em>Tetraselmis chuii</em> was evaluated for its effect on survival, growth and oxidative stress biomarkers on <em>Litopenaeus vannamei</em> postlarvae (PL). The antioxidant properties of the formulated feed with <em>T. chuii</em> inclusion were determined using four antioxidant chemical assays. Meanwhile, the oxidative stress biomarkers on PL were analyzed by hydrogen peroxide, membrane stability and lipid peroxidation assays. Results showed that PL reared on diets supplemented with 50% <em>T. chuii</em> had a significantly higher (<em>P</em> ≤ 0.05) survival (97.6 ± 1.4%) and lower oxidative stress in terms of hydrogen peroxide content (10.08 ± 0.4 mM g−1 FW) and electrolyte leakage (10.8 ± 0.3%). The result of this study also showed that shrimp PL reared on diets supplemented with microalgal, <em>T. chuii</em> have high resistance to reverse salinity stress test (76.7–100%). However, no significant differences (<em>P</em> ≥ 0.05) were found in the growth and lipid peroxidation. Due to the positive effect on oxidative stress status, survival and resistance to salinity stress, the feeding of <em>L. vannamei</em> PL with diet containing at least 50% of <em>T. chuii</em> is recommended as a natural source of antioxidant for PL.