A CpG DNA adjuvant in avian vaccines is disclosed, which includes an
immunostimulatory oligodeoxynucleotide (ODN) having a sequence of SEQ ID
NO: 2. The CpG DNA adjuvant in avian vaccines is advantageous to carry
out large-scale production, specifically enhance avian innate and
adaptive immune responses, and the CpG DNA adjuvant is hardly to be
digested by DNase due to its particular structures.