Effects of Padina australis (Hauck) polysaccharide extract on growth, antioxidant and nonspecific immune parameters of the western white leg shrimp, Litopenaeus vannamei (Boone)

This study aimed at determining impacts of various amounts of water-soluble polysaccharide extracts from brown algae, Padina australis (Hauck) (WPP) on actions of antioxidant enzymes, the growth, and non-specific immune response of shrimp, Litopenaeus vannamei (Boone).Triplicate groups of shrimp (1 ± 0.1g) have been given feed 4 isonitrogenous and iso-lipidic diets composing of 4 levels; that is, 0 (control), 0.5, 1.0, and 1.5 g kg -1 of WPP extract for eight weeks.Analyses showed that significantly positive effects of diets with 1.0 g kg -1 of WPP extract on the growth function of the studied groups.Additionally, improvements of the antioxidant enzyme activities, such as catalase, malondialdehyde, super-oxide dismutase, and glutathione peroxidase via feeding 0.5 and 1 g kg -1 of WPP extracts.