Objective:To investigate the activity of Egyptian propolis extracts(ethanol and water)on cryptosporidiosis in experimentally infected dexamethasone-immunosuppressed rats.Methods:A total of 180 male rats(190-220)g BWt were randomly divided into 9 equal groups(G1-G9).Groups of rats were kept as(G1):normal control,(G2-G9):immunosuppressed with dexamethasone and(G3-G9):infected with Cryptosporidium oocysts.Rats from(G4to G9)were given orally ethanol and water extract of propolis(at a dose of 50 mg/kg BWt)and nitazoxanide(standard anti-cryptosporidial drug at a dose of 100 mg/kg BWt)to infected rats with different regimes.Faecal pellets were collected from all groups to monitor oocysts shedding from the 2nd to the 15th day post infection.At the end of the experiment,blood was collected from all groups for determination of leukogram and serum proteins.Ileum specimens were also examined histopathologically.Results:The highest reduction of oocysts shedding in faecal samples was 88%in rats prophylactically treated with propolis ethanol extract at the 4th dpi,and in rats prophylactically treated with water extract of propolis,was91%at the 6th dpi.There was a marked increase in neutrophils count and α_2-andβ-globulins levels in infected rats treated with both extracts,while a significant decrease was detected in lymphocytes compared to the infected non treated group.β-globulin level markedly increased in the rats administered nitazoxanide.Histopathological changes were observed in the ileum of rats infected with Cryptosporidium.Conclusions:Egyptian propolis extracts have an activity on cryptosporidiosis in rats.Moreover,propolis modulated the immunity in dexamethasone-immunosuppressed rats. Objective: To investigate the activity of Egyptian propolis extracts (ethanol and water) on cryptosporidiosis in experimentally infected dexamethasone-immunosuppressed rats. Methods: A total of 180 male rats (190-220) g BWt were randomly divided into 9 equal groups G9). Groups of rats were kept as (G1): normal control, (G2-G9): immunosuppressed with dexamethasone and (G3-G9): infected with Cryptosporidium oocysts. of propolis (at a dose of 50 mg / kg BWt) and nitazoxanide (standard anti-cryptosporidial drug at a dose of 100 mg / kg BWt) to infected rats with different regimes.Faecal pellets were collected from all groups to monitor oocysts shedding from the 2nd to the 15th day post infection. At the end of the experiment, blood was collected from all groups for determination of leukogram and serum proteins. Elemental specimens also also examined histopathologically. Results: The highest reduction of oocysts shedding in faecal samples was 88 % in rats prop hylactically treated with propolis ethanol extract at the 4th dpi, and in rats prophylactically treated with water extract of propolis, was 91% at the 6th dpi. where a marked increase in neutrophils count and α_2-and β-globulins levels in infected rats treated with both extracts, while a significant decrease was detected in lymphocytes compared to the infected non treated group. β-globulin level markedly increased in the rats administered nitazoxanide. Histopathological changes were observed in the ileum of rats infected with Cryptosporidium. Conclusions: Egyptian propolis extracts have an activity on cryptosporidiosis in rats. Moreover, propolis modulated the immunity in dexamethasone-immunosuppressed rats.