Immunogenicity and effectiveness of vaccines against bovine brucellosis

Abstract

Vaccination of production animals with Brucella spp. live strains is one of the major measures for brucellosis control worldwide, aiming both human and animal health. However, although vaccine strains have been widely studied, there are still many aspects for being clarified. This thesis contains four chapters: (1) “Efficacy of Brucella vaccine strains: S19, RB51 and Rev-1” and (2) “Does lipopolysaccharide morphology (smooth or rough) of Brucella abortus vaccine strains influence the potency or efficacy of the vaccine?”; (3) “Systematic review on the effectiveness of Brucella abortus S19 and RB51 vaccine strains in field studies”; and (4) “Short communication: Effects of age on the immune response induced by Brucella abortus S19 or RB51 vaccination in calves”. The principal scientific contributions were: (1) clarification of various aspects about dissociation of smooth Brucella strains and its use for bovine vaccination; (2) confirmation of the effectiveness of B. abortus S19 and RB51 vaccines in the field, particularly when combined with other control policies; and (3) observation of similar immunogenicity of the S19 and RB51 strains in calves vaccinated at different ages within the 3 to 8-month range.