Efficacy improvement of tri-serotypes vaccine for Salmonella using nanomaterial-based adjuvant in chicken

Abstract Background This study aimed to develop a vaccine for controlling salmonellosis, a zoonotic disease affecting both humans and chicken, by employing Fe2O3 ferrous iron oxide (FNPs), silicon dioxide (SiNPs), carboxymethyl chitosan (C.CS NPs), and FNPs-chitosan (FCNPs) nanocomposite as immunological adjuvants. The immune response of vaccinated chicken was assessed through ELISA and challenge tests. Results The hydrodynamic diameters of Fe2O3, Fe2O3-CS, C.CS, and SiO2 NPs were found to be 81.95 ± 14.95, 137.1 ± 20.5, 32.86 ± 14.05, and 15.64 ± 3.6 nm, respectively. The incorporation of nanoparticles into the vaccine formulation significantly enhanced its efficacy by eliciting a robust immune response. According to the study, FNPs, SiNPs, C.CS NPs, and FCNPs can be used as immunological adjuvants to strengthen chicken’s immune systems and help prevent salmonellosis. By gradually raising antibody titers, all five vaccine formulations successfully stimulated an immunological response against Salmonella in vaccinated chicken. The size of the immunological response, however, differed amongst the various vaccination formulations. The SiNPs group had the highest antibody titer, followed by the locally administered vaccine. Conclusions These findings suggest that the use of silicon dioxide SiNPs as a vaccine delivery system could enhance the immune response to Salmonella in chicken. Overall, the study demonstrates that the use of adjuvanted vaccines with nanomaterials, particularly SiNPs, has significantly increased the protection rate from 67 to 93.3% when compared to the locally used vaccine, which had a protection rate of 83%.