From Classical Bacterins to Recombinant Vaccines: Critical Aspects of the Immune Response in Ruminants

from renal and probably also genital tissues. Thus, overcoming chronic colonization through inducing the Th1-type immune response may be the main challenge for vaccination to fulfill its role in sustaining herd immunity and mitigation of zoonotic risk, in line with the One Health approach. In this context, we aimed to critically examine immune mechanisms in ruminants, advances in vaccine platforms and adjuvant strategies against bovine leptospirosis and outline the challenges that must be overcome to achieve sterilizing immunity.