The effect of immunisation with BCG on Theileria parva infection in cattle.

Cattle were immunised with 10 8 bacillus Calmette-Guerin (BCG) organisms 32 days before challenge with a lethal dose of Theileria parva stabilate. The disease reactions of immunised and control cattle were similar and all infected cattle died. It is suggested that the failure of BCG to protect cattle against T parva infection is because the cattle response to this non-specific immunisation is poorly developed.