Retrospective Study on the Prevalence and Seasonal Patterns of Bovine Tuberculosis in FCT, Abuja, Nigeria

Abstract

Bovine tuberculosis (bTB) caused primarily by Mycobacterium bovis, remains a significant zoonotic and economic concern in Nigeria. This retrospective cross-sectional study analysed post-mortem records of 20,144 cattle slaughtered across four major municipal abattoirs, Dei-Dei, Gwagwalada, Kubwa, and Karu in the Federal Capital Territory (FCT), Abuja, between January 2022 and December 2024. Data stratified by season, sex, age, and body condition score (BCS) were analysed using descriptive statistics, Chi-square tests, and Odds ratios at a significance level of p ≤ 0.05. Of the 20,144 cattle slaughtered across the abattoirs, 1,711 had tuberculosis-like lesions, yielding an overall prevalence of 8.49% (95% CI: 8.11–8.88). Abattoir-specific prevalence varied markedly, with cattle slaughtered at Karu abattoir recording the highest tuberculosis burden (21.60%), while those slaughtered at Kubwa had the lowest (0.43%). Seasonal analysis revealed significantly higher prevalence in the dry season (13.55%) than in the rainy season (1.81%) (χ²=875.6; p<0.0001; OR=0.12). Adult cattle and females exhibited increased susceptibility to tuberculosis, with prevalence rates of 11.76% and 11.47%, respectively, compared to 2.64% in young and 5.00% in male cattle (p<0.0001). Poor body condition was also associated with higher prevalence of infection (p<0.0001). Anatomical distribution of lesions indicated a strong respiratory predilection, predominantly affecting the lungs (43.37%), mediastinal lymph nodes (26.77%), and bronchial lymph nodes (20.51%), with limited extrapulmonary involvement. These findings highlight pronounced spatial, seasonal, and host-related variations in bTB occurrence among cattle slaughtered within FCT abattoirs and underscore the need for targeted surveillance and control strategies, particularly during the dry season and among high-risk subpopulations.