Abstract:Objective: To study the inhibitory effect of compound Yulangsan polysaccharide (CYLSP) on duck hepatitis B virus (DHBV) persistent infection. Method: One-day old Guangxi brown spotted ducks infected with hepatitis B virus (DHBV) were used as the DHBV infected animal model. Fifty positive ducks were detected by PCR at one week after the infection of DHBV, then randomly divided into 5 groups, each group of 10, only CYLSP high, medium and low dose group (10,5,2.5 g·kg-1) and lamivudine (0.05 g·kg-1) group and model group, the daily morning lavage l time for 14 d. Alanine aminotransferase(ALT), aspartate aminotransferase(AST) in serum were detected before treatment (T0),7 days (T7),14 days (T14) after treatment, and 3 days after stopping treatment. At 3 days after stopping treatment, the livers were collected,homogenate was prepared to detect superoxide dismutase(SOD), glutathione peroxidase(GSH-Px) activity and reduced glutathion(GSH),malondialdehyde(MDA) levels, HE staining was used to observe the pathological change. Result: Compared with T0 and model group, the serum levels of ALT and AST were decreased significantly and 3 days after stopping treatment,CYLSP high dose group and lamivudine group still showed a protection effect (P<0.05 or P<0.05) SOD,GSH-Px activity and the content of GSH,MDA.CYLSP in high, middle dose group and lamivudine group showed a protection action. In CYLSP low dose group, no change of SOD,GSH-Px activity and GSH,MDA content was found,HE staining showed CYLSP significantly reduced the duck liver histopathologic damage degree. Conclusion: The compound Yulangsan polysaccharide has a protection action on duck liver injury induced by duck hepatitis B virus