Immunoprophylactic efficacy of 35 and 43 kDa midgut antigen of Rhipicephalus haemaphysaloides in rabbits^†

Two immunoreactive polypeptides (35 kDa and 43 kDa) of Rhipicephalus haemaphysaloides midgut protein were extracted from sodium dodecyl sulphate-polyacrylamide gel (SDS-PAGE) bands. The gel bands were lyophilized and used to immunize rabbits in group I (35 kDa polypeptide) and group II (43kDa polypeptide). The immunized animals received 3 doses of inoculum containing the polypeptide at 0,14 and 21 day with Freund's complete adjuvant. After tick challenge on day 35, a highly significant (P£ 0.01) reduction in the feeding and fertility parameters of ticks like number, weight, oviposition capacity and larval mass weight was observed in the tick population that had fed on immunized animals as compared to control animals. The results suggested that immunoprophylactic efficacy (74.0%) with 43 kDa antigen was slightly higher in group II when compared to group I (72.10%) immunized with 35 kDa polypeptide.