Seroprevalence, Spatial Distribution, and Risk Factors of Bovine Brucellosis in Pastoral Herds of Benin.

Résumé

Bovine brucellosis remains insufficiently assessed in Benin. This study aimed to estimate the seroprevalence of the disease, map its geographic distribution, and identify associated risk factors.  The study was conducted across 520 cattle herds. A herd identification form was developed and completed using the KoboCollect application. Serum samples were analyzed using an indirect enzyme-linked immunosorbent assay (iELISA). The results revealed disparities in bovine brucellosis prevalence among herds and agroecological zones. The herd-level prevalence rates for AEZ1 to AEZ8 were 12.48%, 11.11%, 4.6%, 13.8%, 12.48%, 7.8%, 2.7% and 4.9% respectively. At the AEZ level, the respective prevalence rates were 89.23%, 61.54%, 41.62%, 92.31%, 86.15%, 52.31%, 38.46% and 43.08%. Significantly higher prevalence was observed in AEZ4, AEZ1 and AEZ5 (p < 0.001). Correspondence analysis revealed four major zone clusters with associated risk factors: Group 1 (Zones 1 and 2): Characterised by white Fulani zebu, cotton farming, cross-border transhumance and Goudali zebu. Group 2 (Zones 3 and 5): Defined by Dendi ethnicity, a lack of veterinary care, Borgou and Bariba cattle breeds, contact with wildlife, and uncontrolled breeding practices. Group 3 (Zone 4 only): Distinguished by Somba ethnicity, White Fulani × Somba crossbred cattle, exposure to wildlife, and uncontrolled breeding. Group 4 (Zones 6, 7 and 8): Marked by the presence of hired labour and White Fulani zebu. The spatial distribution of these prevalence rates was mapped in detail.  This study enhances our understanding of the epidemiology of bovine brucellosis in Benin, providing critical insights for more effective disease control measures.