Sero-diagnosis of bovine tuberculosis by ELISA using bovine PPD and ST.CF.

Abstract. Bovine tuberculosis represents one of the very important infectious diseases in Egypt and the world. It has zoonotic importance and causes severe economic losses. Accurate and rapid diagnosis considered as the milestone for control of the disease. In this study ELISA technique was used for confirmation of positive reactors cows that tested with single intradermal tuberculin test, to detect false positive reactors. Bovine PPD and ST.CF antigens have been used as two different coating antigens for ELISA technique. 3747 cattle from dairy farms in five different governorates were subjected to the single intradermal cervical tuberculin test whereas 78 (2.24%) proved positive reactors to tuberculin. These positive reactors tested with ELISA. 64 (82.05%) animals were positive by ELISA coated with ST-CF, while by using bovine PPD as coating antigen 58 (74.35%) animals were positive. The previous results indicated that ELISA test showed higher sensitivity and specificity using ST-CF as coating antigen than in case of bovine PPD coating antigen. Key words