vaccination of cattle against theileria annulata in an endemic area in egypt

The present study is dealing with a trial for applying theileriaannulata tissue culture vaccine (Egyptian strain) in field condition.This study was carried out in EI-Kharga Oasis, New Valley Governorate as it was an endemic area for Theileriosis (LiebiS’chch et al.,1984). Therefore, it was intended to apply and find outthe reaction of using theileria annulata attenuated schizontculture vaccine in that field. Field diagnosis of 690 Frisiancalves of less than one year old, from private and governoratefarms were carried out for thileria annulata infection. Thediagnosis based on Giemsa stained blood smears and on the seraof cattle by IFA test. The demonstration of the clinical casesby blood smears examination revealed that approximately 95.07% were positive for Theileriosis. Serological examination ofnegative animals by IFA test revealed that 25 out of 34 animals(73.5 %) were serologically free from t. annulata antibodiesand only 9 animals (26.5 %) contain circulating annulata antibodies. The free calves from infection were used in thepresent work as experimental animals.The work based on two experiment for detection theefficiency of vaccine in calves naturally challenged with ticksin field condition (experiment ”1”) and in calves experimentally challenged with newly hatched ticks (experiment ”11”).