Detection and Quantification of Mycobacterium tuberculosis Complex Bacilli in Slaughtered Cattle, at Yola, Adamawa State, Nigeria

Abstract

Bovine tuberculosis (bTB) is a neglected zoonotic disease of major public health and economic importance in Nigeria. This study determined the prevalence of Mycobacterium tuberculosis complex (MTBC) among slaughtered cattle at Yola Modern Abattoir, Adamawa State, using liquid and solid culture methods. A cross-sectional abattoir-based study was conducted in which 190 bovine lung samples with lesions suggestive of tuberculosis were collected. Samples were processed using Petroff’s decontamination method and cultured in the Mycobacteria Growth Indicator Tube (MGIT 960 BACTEC system) and on Lowenstein–Jensen (LJ) media supplemented with glycerol and pyruvate. MTBC-positive cultures were confirmed using the SD Bioline™ TB Ag MPT64 assay. Out of 190 samples examined, 85(44.7%), were posistive for MTBC by TB-MBLA, 73 (38.4%) were positive for MTBC by liquid culture, while 45 (23.7%) were positive by solid culture. TB-MBLA, showed the highest detection rate followed by Liquid culture and the least being solidculture method (χ² = 19.34; p = 0.000). Based on TB-MBLA results, the apparent prevalence of bovine tuberculosis was 44.7%. The high prevalence observed confirms the endemicity of bovine tuberculosis among cattle slaughtered in Yola and indicates a substantial increase compared with earlier reports from the area. The practice of selling carcasses after removal of affected organs poses a significant zoonotic risk to abattoir workers and consumers. Strengthening meat inspection, implementing active surveillance, and adopting effective national bTB control strategies are urgently needed to reduce transmission and protect public health. Keywords: Mycobacterium tuberculosis complex, bovine tuberculosis, Mycobacterium growth indication tube, BACTEC 960, Lowenstein-Jensen medium, TB-MBLA