Irrelevance between the induction of anti-Campylobacter humoral response by a bacterin and the lack of protection against homologous challenge in Japanese Jidori chickens

Abstract

On-farm vaccination of chickens against Campylobacter jejuni is considered a potentially effective countermeasure to decrease campylobacteriosis via consumption of contaminated chicken meat, but is not yet available. In this study, 2 groups of Jidori chicks were immunized subcutaneously with a formalin-killed C. jejuni with 2 different adjuvants. Other chicks served as the unvaccinated control group. Both vaccines induced high levels of anti-Campylobacter IgG but did not decrease bacterial excretion in cecal droppings and bacterial load in the liver and spleen after oral challenge with 10 5 CFU of the homologous strain. Further study is needed to address the observed irrelevance and to develop a novel effective vaccine against C. jejuni. © 2012 The Japanese Society of Veterinary Science.