One hundred SPF chickens were divided equally into 5 groups. The chickens of 3 groups(A,B,C) were infected after being immunized with infectious bursal disease(IBD)recombinant subunit double emulsion vaccine.

• 100只SPF鸡均分为5组,A、B、C3组免疫后攻毒,接种3批次自制的IBD基因工程重组亚单位油乳剂疫苗;