Sero-diagnosis of Bovine tuberculosis using a rapid lateral flow test and ELISA in dairy cattle in Egypt

Mycobacterium bovis (M. bovis), the cause of bovine tuberculosis (BTB) in cattle, remains a major zoonotic and economic problem in many countries. This study aimed to apply different serological tests for detection of bovine tuberculosis as a complementary for intradermal tuberculin test. The tested 4250 cattle in different Egyptian governorates by single intradermal cervical comparative tuberculin test (SICCT), 90 (2.1%) cattle reacted positively. The postmortem (PM) examination of the positive reactors revealed 65 (72.2%) out of 90 slaughtered cattle with visible lesions (VL) while the other 25 (27.8%) reactors showed no visible lesions (NVL). The visible lesions detected in head were 10 (15.4%) out of the 65 VL, in respiratory system were 32 (49.2%), in the digestive system were 5 (7.7%), in mixed infection were 11 (16.9%), and in generalized infection were 7(10.8%). The bacteriological examination of processed samples from the 90 slaughtered cattle revealed 55 M. bovis (61.1%); 51 (78.5%) were from 65 VL and 4 (16.0%) were from 25 NVL. Enzyme linked immune sorbent assay (ELISA) was used for the tuberculin positive animals’ sera and gave 36 (55.4%) out of 65 cattle with and 2 (8%) out of 25 cattle with NVL by a total 38 (42.2%) out of the 90 tuberculin positive animals. The results of lateral flow test gave 32 (49.2%) out of 65 cattle with VL and 1 (4%) out of 25 cattle with NVL by a total 33 (36.7%) out of the 90 tuberculin positive animals.