This study was initiated to evaluated CATT test in comparison with PCR for detection of Trypanosoma evansi infection in donkeys in Egypt. Six donkeys free from T. evansi were inoculated with T. evansi strain (Egypt CD2) which had been isolated from naturally infected horse. Parasitological examination of the donkeys revealed a prepatent period of T. evansi 1- 4 DPI. Two blood samples (heparinized and plain) were taken from each donkey every 4 days starting from day 0 until the end of the experiment for serological examination (CATT/ T. evansi). Body temperature was also estimated. Serological examination of the experimentally inoculated donkeys' no.1, 2, 4 and 5 showed that seroconversion occurred on 12 DPI and remained until death of animals. Other experiment, blood samples from 416 donkeys collected randomly from different governorates of Egypt, they were tested parasitologically (stained blood smear, mice inoculation (MI) and microhaematocrit centrifugation technique (MHCT) and serologically by using CATT/ T. evansi for diagnosis T. evansi infection. From the previous animals, 26 parasitologically negative donkeys were used for comparison between the results
obtained by CATT/T. evansi & PCR techniques. Of 26 parasitologically negative samples, 9 (34.6%) & 14(53.85%) samples were found positive by using CATT and PCR techniques respectively. Despite of the simplicity and low-coast of CATT test, it is recommended to use it in combination with PCR technique for accurate and reliable results.