Specificity and effects of host resistance on the African tick Rhipicephalus zambeziensis (Acarina: Ixodidae).

Repeated infestations of the rabbit with adult Rhipicephalus zambeziensis ticks resulted in a ten-fold reduction in engorgement weight of adult ticks and a significant decline in engorgement weight of nymphs. There was no evidence of cross-resistance against the South African bont tick, Amblyomma hebraeum. Immunization of rabbits with crude extracts of whole-tick protein significantly influenced engorgement weights and oviposition rates of adult R. zambeziensis. Histological studies of tissues from R. zambeziensis adults fed on resistant rabbits showed severe gut damage; this was associated with the binding of host IgG to mid-gut cells.