Objective: To understand the characteristics of Japanese encephalitis virus strains in miniature pigs.
Methods: The porcine brain tissue was treated, inoculated with BHK21 cells, and subjected to virus culture, indirect immunofluorescence test, neutralization test, electron microscope observation, and amplification of the newly isolated strain E region by reverse transcription-polymerase chain reaction (RT-PCR). Segment and PrM segment nucleotide sequences were sequenced for genotype identification.
Results: 25 pig brain tissues were inoculated with BHK21 cells, and 3 tissue treatment solutions could cause BHK21 cells to undergo rounding, agglomeration and other lesions; the BHK21 diseased cells inoculated in 3 tissues were subjected to immunofluorescence test, and all produced strong green fluorescence reaction The neutralization test results showed that the neutralization titers of the three new isolates were 1∶64; spherical virus particles with a diameter of about 40 nm were seen under the electron microscope; RT-PCR product sequencing results were homologous to the nucleotides in the E segment of the vaccine strain The genotypes were all 95%; the 3 new isolates were all GⅢ encephalitis B virus.
Conclusion: The experiment shows that there is Japanese encephalitis virus infection in small pig farms, which is GIII Japanese encephalitis virus.