Growth, Fatty Acid Composition, Antioxidant Activity and Resistance of Litopenaeus vannamei Fed With Dunaliella salina

In order to determine the effect of Dunaleilla salina extract (DE) as feed supplement on the fatty acid composition, growth performance, anti-oxidant activity, as well as resistance of shrimp ( Litopenaeus vannamei ) challenged with Photobacterium damselae bacteria, we performed an eight-week trial. Post-larvae shrimps with the initial weight of 0.86 ± 0.1 g have been stocked randomly into four different trial groups with three replications and fed with inclusion levels of 0, 0.05, 1 and 1.5 g kg −1 of DE. After eight weeks of experiment, thirty shrimps from each of the dietary group have been exposed to the bacteria P. damselae over 10 days. Based on the findings, DE can be used as one of the growth promoters for L. vannamei . Specific growth ratio, weight gain and protein efficiency ratio significantly increased ( P < 0.05) in shrimps fed by DE1 diet in comparison with other groups. In addition, it has been determined that inclusion of 0.5 and 1 g kg −1 DE significantly enhanced ( P < 0.05) of the poly-unsaturated fatty acids (PUFAs) in the body. especially linolenic acid (LNA;C18:3n-3). eicosapentaenoic acid (EPA;C20:5n-3), linoleic acid (LOA;C18:2n-6), docosahexaenoic acid (DHA;C22:6 N-3. The highest phenoloxidase (PO), glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities have been determined in shrimps fed by DE0.5 and DE1 diets. Also, the minimum rate of death has been seen in the DE1 supplementary diet after exposure to P. damselae. Overally, results indicated that inclusion levels of D. salina extract in 1 g kg −1 dose enhance growth, fatty acid composition, antioxidant activity and resistance of the shrimp L. vannamei as opposed to the P. damselae infection.