Objective To evaluate the distribution of Mongolian gerbil hepatitits virus(MGHV) and histopathological changes in the digestive tract of infected Mongolian gerbils.Methods The gerbils were grouped by four ages.Streptin-biotin-complex immunohistochemistry and serology test(ELISA)were applied to examine the pathological change and determine the virus in the digestive tract.Results The results showed that the infected gerbils dipicted widespread necrotic foci in the liver in all age groups.The boundory between hepatocytes was unclear.The hepatocytes appeared in different size and color,and some of them were degenerated.The MHV(murine hepatitis virus)-positive reaction mainly distributed in the endothelial and Kupffer's cells around sinusoids.The ratio of MHV-positive hepatocytes was relatively low and dispersed.There were uniform MHV-positive particles in MHV positive hepatocytes.In the stomach,the MHV-positive reaction was mainly located in the bottom and of the pit and cervical part of the fundic glands and limited locally.The MHV-positive cells were mainly chief cells.In the intestine,the main pathological changes were presented as lymphocytic infiltration in the lamina propria and between the mucosal epithelial cells.The control group showed to be negatively stained.Conclusion Mongolian gerbils bred in the open system are susceptible to MGHV infection and causing inflammatory infiltration in the liver,stomach,colon and cecum.The virus mainly replicated in the liver sinusoids,endothelial cells,Kupffer's cells and gastrointestinal mucosal epithelium.The use of immunohistochemical technology in pathological examination of the digestive system in gerbils is an effective diagnostic approach to detect Mongolian gerbils infected with MGHV.