1.Sequencing analysis of whole genome of one strain of bovine Akabane virus and es-tablishment of fluorescence quantitative PCR for virus detection
Jiafu SHANG ; Le HU ; Mingke LI ; Yujian WU ; Xingwei NI ; Xiaowei YANG ; Xia LIU ; Liwu ZHANG ; Tingting XU ; Guangwei ZHAO
Chinese Journal of Veterinary Science 2024;44(9):1872-1881
In order to understand the prevalence of Akabane disease(AKAD)in Guizhou Province and the molecular characteristics of the isolates,the whole-genome sequence of a strain of Akabane virus(AKAV)from a bovine AKAD-positive sample was determined and analyzed.The genotype and genetic variation of the strain were also explored.Based on the conserved S sequence,a fluores-cence quantitative PCR(qPCR)detection method was established and applied for the investigation of AKAV infection status in four large-scale beef cattle farms of Guizhou.Results showed that the S,M and L fragments of the bovine strain were highly homologous to the Tianjin strain(TJ2016/China/2016)and the Australian strain(JaLAB39/Australia/1959),where they were in the same evolutionary branch and belonged to genotype Ⅱ.Sensitivity assay found that the lowest detection limit was 2.5 X 101 copies/μL.Specificity assay showed the established method detected only AKAV with no amplification on bovine bluetongue virus(BLUV),Pasteurella multocida(PM),bovine infectious rhinotracheitis virus(IBRV)and bovine Mycoplasma bovis.The variation coefficients of inter-and intra batches in the repeatability test were both lower than 2.26%.These findings illus-trated that the established qPCR method had high sensitivity,good specificity and repeatability.A total of 298 serum samples from 4 large-scale beef cattle farms in Qianxi City and Huangping County of Guizhou Province were collected and tested for AKAV by the method.Out of 298 sam-ples,25 positive samples(25/298)were detected as positive with a positive rate of 8.39%.In sum-mary,this work provided the reference data for a deep understanding of the molecular prevalence of AKAV in Guizhou Province and laid foundation for the prevention and control of AKAD.