Parasitemia and rectal temperatures were determined in Yankasa sheep experimentally infected with Trypanosoma congolense and immunomodulated with levamisole. Group A (6 sheep) and group B (6 sheep) were infected with 2 x 106T. congolense parasites. In addition Group B sheep were each administered with 2.5 mg/kg levamisole hydrochloride subcutaneously on the day of infection and later weekly throughout the experimental period. Group C (5 sheep) served as the uninfected controls. Parasitemia in the T. congolense infected immunomodulated group appeared 2 days earlier than the group with T. congolense infection only and the parasitemic level was also higher in the infected immunomodulated group at the first parasitemic peak. Rectal temperatures were significantly (p < 0.001) higher in the infected groups when compared the control but were not significantly different (p > 0.05) between the infected groups. It appears that levamisole immunomodulation of T. congolense sheep enhanced the early appearance of parasitemia but was not associated with mortality as all the infected animals survived the experimental period which lasted 6 weeks.
