Pig contagion Characteristic gastroenteritis attenuated virus, the create modulo and its application

摘要

PURPOSE:To obtain an attenuated virus of TGE, resistant to proteinase and/or acid and proliferable in intestines after nasal or oral administration, by the mutagenic treatment of attenuated virus of TGE. CONSTITUTION:An attenuated virus of transmissible gastroenteritis of swine (TGE) is produced by the serial subculture (about 100-180 generations) of a pathogenic TGE virus on a cultured cell of swine. The attenuated virus is subjected to mutagenic treatment such as ultraviolet ray treatment, X-ray treatment or nitrosoguanidine treatment and a virus clone is separated by immediate plaque cloning. Each of the clone is proliferated on a cultured cell of swine, the obtained virus liquid is treated with a proteinase and/or acid and inoculated to a monolayer culture medium for cultured swine cell to effect recovery and proliferation of survived virus. The proteinase or acid treatment and the recovery and proliferation operation of the survived virus are repeated for at least 12 generations to obtain an attenuated TGE virus which can be proliferated on a mucous membrane of intestine.