Comparative assessment of the immunogenicity of a chitosan-based drug in combination with vaccine strains of the Newcastle disease virus

Chitosan, which combines mucoadhesive and sorption properties, is of interest as a promising vaccine adjuvant. This article is focuses on a comparative assessment of the immunogenicity of various vaccine strains of Newcastle disease virus used in combination with chitosan. In groups of chickens, the levels of antibodies were studied in response to immunization with vaccines containing the La Sota and B1 strains of Newcastle disease virus with and without chitosan. There was no local irritant effect or general toxicity of the studied drugs when they were administered to 14-day-old chickens. It was found that chitosan increased the immunogenicity of the experimental vaccines compared to the control vaccines in terms of serum antibody titers. However, its immunogenicity was not the same when combined with different vaccine strains. The highest increase in antibodies was observed when chitosan was combined with the B1 strain vaccine. Сhitosan is safe for chickens and has the ability to nonspecifically increase the immunogenicity of vaccines against Newcastle disease in birds. Its adjuvant effect differs in relation to various vaccine strains of the virus.