NOVEL INFECTIOUS BURSA FABRICII'S DISEASE VIRUS AND VACCINE CONTAINING THE VIRUS

摘要

Separation of a novel infectious bursa fabricii's disease (IBD) virus that cannot be combated with the conventional IBD vaccine; and a novel vaccine effective against the virus. Novel IBD virus TY2 strain was separated and it s substrain was obtained. In the TY2 strain, a gene coding for a hypervariable region of VP2 being a principal host defense antigen site of the virus is no t cleaved by TaqI and SspI but cleaved by MvaI into about 52 bp and about 422 bp fragments. Thus, the TY2 strain has a genotype different from that of known IBD viral strain. Excellent vaccine against IBD can be obtained from the TY2 strain or a substrain of the virus.