Abstract: Objective To establish murine model for ocular toxoplasmosis and observe the fundus and pathological changes. Methods 20 BALB/C mice were randomly divided into the control and experimental group with 10 mice per group. In the experimental group, mice were fed orally with toxoplasma type Ⅱ PRU strains cyst. Changes of fundus were observed daily and fundus photography were taken after 1 month, 2 months and 3 months, respectively. After 3 months, serum IgG of the mice was detected by ELISA assays. The mice were sacrificed and the eyes were harvested. Pathological damages of retina and choroid tissue were observed after HE staining. Results After two weeks, fundus inflammation was noticed in the experimental group, including optic disc edema, retinal angioplerosis, edema and hemorrhage along with retinal vascular, from the beginning of the optic disc area gradually expanded to the surrounding blood vessels. These changes aggravated with time. Significant titers change in serum IgG, significant higher than the control group (P<0.001), from the retinal and choroid tissue slice of the experimental group mice, we could see the retinal and choroid apparent edema, the gap between the organization was loose, lacuna was formed,inflammatory cell infiltration was found in tissue of retinal and choroid. Conclusion Infecting mice with type Ⅱ toxoplasma PRU strains via oral route could be a good way to establish animal model for ocular toxoplasmosis, which can cause inflammation of the choroid and retina.

Key words: Fundus change, Inflammation, Pathological observation, Ocular toxoplasmosis