The invention discloses an
antigen fusion protein and application thereof in preparation of a live vaccine for preventing
infectious bursal disease. Specifically disclosed are
antigen fusion proteins comprising a VP2
protein, a
trimer tag, and a C3d
protein. The invention also discloses recombinant
Eimeria heap constructed by using the
antigen fusion protein and application of the recombinant
Eimeria heap in preparation of IBDV live vaccines. The oocyst of the recombinant
Eimeria heap can effectively induce humoral immune response aiming at IBDV as a vaccine
active ingredient, the level of an induced
antibody is obviously higher than that of an
insect strain expressed by a single VP2 antigen, viruses can be more effectively neutralized, the
immune protection efficacy is improved, the safety is high, and the oocyst has the potential of serving as a live vector
genetic engineering vaccine. The IBDV live vaccine can be orally taken through drinking water or feed,
vaccination is simple, large-scale immunization of chicken flocks can be achieved, and the IBDV live vaccine is economical and efficient and has a wide prospect of being applied to prevention and control of the IBDV of the chicken flocks.