Evaluation the immunity of Neospora caninum attenuated strain in preventing oocyst shedding in dogs

The protozoan Neospora caninum is known worldwide as one of the most important causes of abortion storms in cattles, especially when dogs living in the cattle farms. Currently, the most consideration is on live attenuated vaccines. The main goal of this research is to evaluated live-attenuated Neuspora caninum (NC-a) strain as an effective vaccine to prevent oocyst shedding in dogs. Sixteen dogs were randomly divided into four equal groups including live attenuated strain without adjuvant, acute strains, live attenuated strain with Montanide adjuvant and control group. All the groups were immunized twice, two weeks apart. One month after the second injection, all dogs were challenged orally by acute NC-1 strain. Immune responses were assay by agglutination test and molecular test was used to assess oocyte shedding. The results showed that the immunized group with live attenuated strain with adjuvant produces the highest immune response. Molecular test also showed that the immune response in immunized dogs prevented oocyst shedding after challenge and the best result is in the group of dogs immunized by live attenuated strain with adjuvant. Overall, the results of this study showed that research on the live attenuated Neospora caninum vaccine with oily adjuvants in dogs is secure and effective in creating an immune response and controlling oocyte shedding. In conclusion, this experimental vaccine can be used as a promosing vaccine in towards researches to obtain a succesful vaccine to control neosprosis in dogs.