THE ROUTE OF IMMUNIZATION OF GERBILS WITH LIVE BESNOITIA-BESNOITI AS A FACTOR IN PROTECTION AGAINST LETHAL CHALLENGE

Gerbils (Meriones tristrami) were infected subcutaneously or intraperi toneally with live culture-grown Besnoitia besnoiti at doses ranging f rom 10(-1) to 10(7) endozoites. All animals injected subcutaneously su rvived the infection and were refractory to a lethal challenge dose of 10(7) endozoites given intraperitoneally 6 weeks later. By contrast, gerbils surviving primary intraperitoneal inoculation with 10(2) to 10 (6) endozoites showed a variable survival rate to challenge. All gerbi ls developed antibodies to B. besnoiti regardless of the route of inoc ulation, except for those given 10(1) endozoites intraperitoneally. Th ere was no statistical difference between the immunofluorescent antibo dy titres developed in groups vaccinated subcutaneously or intraperito neally (P = 0.556).