Cultivation of Theileria. I. Attempts to complete the cycle of Theileria parva in vitro.

Microschizonts and free merozoites developed in bovine lymphoblastoid cell cultures containing macroschizonts of 6 different strains of Theileria parva. Clean bovine red cells were added to the cultures, which were incubated in various ways. No penetration of red cells by merozoites was observed, not even when cultures in diffusion chambers were introduced into the peritoneal cavity of non-infected cattle.