Epidemiology and predilection-site distribution of tick infestation in communal cattle systems of Limpopo Province, South Africa.

BACKGROUND

Ticks and tick-borne diseases are major constraints to cattle productivity in sub-Saharan Africa. This study assessed the epidemiology and host-level determinants of tick infestation in communal cattle systems in South Africa.

METHODS

This cross-sectional study examined 787 cattle across 17 villages. Animal-level data included sex, breed (Nguni, Drakensberg, Bonsmara, Brahman, Hereford, Simmentaler, and crossbreeds), age, and body condition score. Tick burden was quantified on six anatomical sites, and whole-body burden was estimated from one-sided counts.

RESULTS

Tick burden was heterogeneously distributed across anatomical predilection sites, with the ears (mean = 50.7 ticks), lower perineum (mean = 44.4 ticks), and upper perineum (mean = 34.2 ticks) exhibiting the highest infestation intensities. Older cattle (> 8 years; IRR = 1.58, 95% CI: 1.39-1.79) and adult cattle (> 2-8 years; IRR = 1.43, 95% CI: 1.26-1.63) harboured significantly more ticks than young cattle (≤ 2 years). Indigenous and crossbred cattle exhibited lower tick burdens than exotic breeds, although breed was not a significant predictor of tick burden after adjustment. Multilevel negative binomial modelling confirmed age and body condition score as independent predictors of total tick burden, while accounting for farm-level clustering. Sex was not a significant predictor, and farm-level clustering accounted for 47% of variance in tick burden. Indigenous and crossbred cattle exhibited lower tick loads than exotic breeds.

CONCLUSION

Tick infestation is prevalent in communal cattle systems in South Africa, particularly in the ears and perianal regions of exotic cattle breeds. These findings provide evidence-based epidemiological data on aggregate tick burden and host-level predictors to inform communal livestock health planning and guide future species-resolved investigations.