Biological and haematological changes in experimental cryptosporidiosis.

In experimentally infected laboratory-bred white rats, Cryptosporidium infection rate was higher among immunosuppressed (75%) than immunocompetent ones (37.5%) with statistically insignificant difference. Cryptosporidiosis was found to be a fatal disease especially in immunosuppressed rats (50%). There was also marked flourishing of the infection as revealed by high intensity of infection in immunosuppressed than the immunocompetent rats (363 and 82.7 oocysts/pellet respectively). In spite of the severe disease, cyclophosphamide appeared to have no effect on the prepatent period. In both immunosuppressed and immunocompetent infected rats, there was a decrease in the total leucocytic count with marked lymphocytopaenia. This indicates decreased resistance to infection, thus higher oocyst counts in the pellets.