The Sensitivity of Gross Necropsy, Caudal Fold and Comparative Cervical Tests for the Diagnosis of Bovine Tuberculosis

• DOI: 10.1177/104063870401600206
• Publication Date: 2011-05-12T20:26:52Z
• Authors: Bo Norby; Paul C. Bartlett; Scott D. Fitzgerald; Larry M. Granger; Colleen S. Brunin...; Diana L. Whipple; Janet B. Payeur
• Keywords: Bovine tuberculosis; Gross examination

Bovine tuberculosis (bTb) was diagnosed in 22 cattle herds the northeast corner of Michigan's lower peninsula. Of these herds, 494 animals 7 were examined by gross necropsy, histopathologic exam, mycobacterial culture, and polymerase chain reaction (PCR) assay performed only on samples that histologically compatible for bTb. Results culture PCR interpreted parallel used as reference test calculation sensitivity 1) caudal fold (CFT), 2) comparative cervical skin tests series (CFTCCT SER ), 3) necropsy. Mycobacterium bovis isolated from 43 animals. Using all sensitivities CFT, CFTCCT , necropsy 93.02%, 88.37%, 86.05%, respectively. When data stratified low- moderate-prevalence 83.33%, 75.0%, 83.33% low-prevalence 96.77%, 93.55%, 87.10% herds. The 2 slightly higher when or more lesions present, significantly ( P = 0.049). CFT found to be notably than most estimates other studies; however, a direct comparison not possible because amount purified protein derivative methods different this study compared with published studies. Although are high, (29%) would have had 1 positive left herd if test-and-removal program been used. This suggests identified, selective culling reactors is less acceptable disease control strategy complete depopulation.