Abstract: Enzootic nasal tumor is a viral transmitted infection of goats, which is caused by enzootic nasal tumor virus (ENTV-2) of goats. After infection, it can lead to irreversible canceration of goat nasal meatus ethmoid epithelial cells, which has been widespread in the world, causing serious economic losses to the goat breeding industry. there is an urgent need to establish a fast, accurate, and quantitative detection method for ENTV-2, we designed primers and TaqMan probes based on the conserved region of the ENTV-2 env gene published on GenBank, and developed a TaqMan probe real-time fluorescence quantitative RT-PCR detection method (qRT-PCR) for ENTV-2, and then verified its specificity, sensitivity, reproducibility, and clinical detection effectiveness. The results showed that the concentration of the recombinant plasmid standard template was 6.30×10²-6.30×10⁷ copies·μL^-1, there is a good linear relationship within the range, with a correlation coefficient of R² of 0.996 5, amplification efficiency of 110%, slope of the linear equation of -2.953, and minimum detection limit of 6.30×10¹ copies·μL^-1; The intra group and inter group coefficients of variation are both less than 2%, indicating good reproducibility; There was no cross reaction with Foot-and-mouth disease virus (FMDV), peste des petits ruminants virus (PPRV), Endogenous retroviruses (ERVs), etc., indicating that this method has good specificity. The qRT-PCR established in this study was used to detect 29 clinical samples, and the detection rate of this method is higher than that of ordinary PCR methods. The above results indicate that this study has successfully established a qRT-PCR for ENTV-2, providing a technical means for rapid diagnosis and epidemiological investigation of ENTV-2.

Key words: enzootic nasal tumor virus of goats, endogenous retroviruses, TaqMan, Real-time quantitative RT-PCR