The application provides a
virus in the preparation of
bacteriophage, and belongs to the technical field of
bacteriophage. The application provides PCV2, phPCV2, PCV3, phPCV3, HEV or phHEV in the preparation of
bacteriophage. The application first proposes that eukaryotic viruses can infect
bacteria and can replicate in the
bacteria, and the viruses show the characteristics of lysogenic bacteriophage. The application has
broad spectrum for the infection of the
bacteria, can effectively inhibit the
reproduction of the bacteria, and has a pioneering significance for developing broad-spectrum bacteriophage bactericides and developing vaccines by using the infection of the viruses on the bacteria. The application can stably amplify the viruses with high
toxicity by using
Escherichia coli, and the inactivated vaccines prepared by the viruses can significantly protect animals. The application also prepares a RecA-deficient
Bacillus subtilis live vector vaccine, so that the
virus infection is stably in a lysogenic state for a long time, and the animals are inoculated by
oral administration, the animals are colonized in the intestinal tract, and the
antigen is continuously expressed to induce a mucosal immune response.