Dr Paria Akbary
Department of Marine Sciences, Chabahar Maritime University, Fisheries group, Chabahar, Iran
This study was conducted to investigate the effects of different levels of water-soluble polysaccharide extract from brown algae, Padina australis (WPP) on growth, antioxidant enzymes activities and nonspecific immune responses of shrimp, Litopenaeus vannamei .Three replicate groups of shrimp (1 ± 0.1g) were fed four isonitrogenous and isolipidic diets containing four levels, 0 or control, 0.5, 1.0, and 1.5 g kg-1 of WPP for 8 weeks. Results show that the diet containing 1.0 g kg-1 of WPP had significant positive effect on growth performance of shrimp. In addition, the activities of antioxidant enzymes including superoxide dismutase, glutathione peroxidase, catalase and malondialdehyde improved by feeding 0.5 and 1 g kg-1 of WPP. Also, the lysozyme and phenoloxidase activities in those of shrimp fed 0.5 and 1 g kg-1 of WPP were significantly higher than those fed control and 1.5 g kg-1 WPP. These results suggested that the use of 1.0 g kg-1 of water-soluble polysaccharides of P. australis can be beneficial for growth, antioxidant and nonspecific immune of L. vannamei.