Growth Yield, Fatty Acid Profile and Antioxidant Status of Litopenaeus vannamei Fed Iyengaria stellata Supplemented Diet

Abstract

This study investigated the impact of the dietary supplementation of the water extract of algae Iyengaria stellata (IE) on the growth performance, fatty acid composition, antioxidant activity and disease resistance of shrimp Litopenaeus vannamei against Photobacterium damselae. A total number of 600 post larvae shrimp L. vannamei (mean 0.86 ± 0.01 g) were randomly divided into four groups (at three replications for each group). The control shrimp group (IE 0) was fed the basal diet free of supplemented IE. Other shrimp groups were fed the basal diet supplemented with IE at levels of 0.5 (IE 0.5), 1 (IE 1) and 1.5 (IE 1.5) g kg−1 diet. Upon the completion of eight weeks of feeding, the challenge test was carried out on 30 shrimps from each experimental group with SK7 strain of P. damselae. After 8 weeks of feeding trail, the shrimp taking IE1 at 1 and 1.5 levels showed a significantly better WG, SGR, PER, FW and PUFA compared to those fed IE 0 and IE 0.5 diets. Adding of IE I to experimental diet, led to significant difference (P < 0.05) in the antioxidant activity. Shrimp fed an IE 1 containing diet, showed the highest PO, CAT, SOD and GPX in comparison with other groups. In addition, incorporation of IE 1 supplemented diet at three doses, significantly reduced mortality percentage following challenging shrimp against P. damselae. The results indicate the positive effect of water extract from brown algae I. stellata at 1 g kg−1 dose, on growth, PUFA and antioxidant activity of L. vannamei and also, showed a remarkable decrease in mortality after challenge with P. damselae.