Preliminary Studies on an Atypical Strain of Bovine Theileria Isolated in Kenya

A theilerial parasite infective for cattle, Theileria sp. (Githunguri), was isolated from the Kiambu District of Kenya through Rhipicephalus appendiculatus ticks. Eight cattle were experimentally infected with Theileria sp. (Githunguri); their reactions were characterized by the production of low numbers of macroschizonts, no microschizonts, few or no piroplasms, anda transient febrile response. All these cattle recovered from clinically mild reactions to infection, but were fully susceptible to subsequent Theileria parva (Muguga) challenge. A cell culture isolate of Theileria sp. (Githunguri) was made from injected lymphoid cells of a reacting animal and, from the resultant in vitro culture suspension, a schizont antigen of the parasite was prepared for the indirect fluorescent antibody test. Serological studies on Theileria sp. (Githunguri), using this test, indicated that it was antigenically distinct from T. parva, T. lawrencei and T. mutans, but had some antigens in common with T. parva and T. lawrencei.