Application of nucleic acid adjuvant in preparation of chicken Marek's disease preventive vaccine

The invention belongs to the technical field of veterinary biological products, and relates to a nucleic acid adjuvant technology of vaccines, in particular to application of a nucleic acid adjuvant in preparation of chicken Marek's disease preventive vaccines. The nucleic acid adjuvant disclosed by the invention is a polynucleotide sequence M7-Inhibitor capable of specifically inhibiting Mdv1-miR-M7-5p, or a chemically modified polynucleotide sequence M7-Inhibitor capable of specifically inhibiting Mdv1-miR-M7-5p, and the M7-Inhibitor nucleic acid adjuvant and an MDV vaccine are combined for use, so that the protective efficacy of the MDV vaccine can be enhanced or improved, the effect of effectively preventing recurrent MDV infection can be achieved, and the application prospect is wide. The vaccine adjuvant can be used as the adjuvant in some existing MD vaccine strains (such as CVI988/Responses) and genetic engineering vaccines, has a good application prospect, and provides a new thought for the research