The Effects of Porphyra yezoensis Polysaccharides on Intestinal Health of Spotted Sea Bass, Lateolabrax maculatus

Porphyra yezoensis polysaccharides (PPs) have biological activities such as promoting digestion, functioning antioxidants, and improving intestinal health. The aim of this study was to investigate the effects PPs on health spotted sea bass (Lateolabrax maculatus). A total 360 (10.53 ± 0.02 g) were randomly divided into six groups. Fish in each group fed with varying PP concentrations (0, 3, 6, 9, 12, 15 g/kg) for 52 days. results showed that 12 g/kg significantly increased body weight gain, specific growth rate, condition factor, while there no significant change feed conversion ratio. supplementation dosage 9 amylase activity, trypsin activity. In addition, compared control group, difference lipase experimental When g/kg, glutathione content increased, malondialdehyde decreased; effect catalase activity not significant. improved morphology, specifically by villus morphology increasing lining surface area. Compared abundance Firmicutes Bacteroides. At genus level, Cyanobacteria, Muribaculaceae, Lachnospiraceae main flora tract bass. ACE Chao1 indices microorganisms, Simpson index Shannon did significantly, indicating microbial composition had a certain extent. indicated different levels can improve physiological biochemical indexes, composition, thus