Contamination survey of laboratory mice in a laboratory animal breeding center to Theiler's Encephalomyelitis Virus

One of the important recommendations of laboratory animals related associations is the use of animals with defined microbial flora because the results of the work on them should be repeatable, reliable and generalizable. Therefore, animal health monitoring is mandatory for certification of their health status at animal breeding and production centers. Mouse hepatitis virus and theiler's encephalomyelitis virus are the most important recommended by FELASA that to examine them in the NIH Laboratory mice colony in this project. The research methods in this study was RT-PCR, using specific primers of the virus. Designing and preparing a positive control sample was carried out using plasmid transformation containing the most appropriate viral gene fragment in E.coli for amplification and extraction. The samples are collected from intestine (colon) containing feces and prepared by standard methods and RT-PCR was performed. The virus theiler's encephalomyelitis, number 13 out of 29 samples with prevalence of 45% among NIH mice were infected with the virus. PCR product was purified and sequenced. In a strain alignment study, it was compared with the eight other species obtained from the NCBI gene. In the phylogenic tree, the KX774639 0.15874 strain belonged to this research most closely related to M20562 from Austria and NC_001366 from England. Because the infection can not be transmitted to humans, immediate removal of the colony is unnecessary.