Epidemiologicalinvestigation of Borna disease virus infection in horses and donkeys in Yili, Xinjiang

Abstract

：Objective To investigatethe epidemiology of BDV infection in Yili horses and Yili donkeys and to analyzephylogenetic source of BDV in Yili area, Xinjiang. Methods We established fluo- rescencequantitative nested RT-PCR to detect BDV p24 segment in peripheral blood mononuclear cells(PBMCs) of 518 Yili horses and 206 Yili donkeys in Yili area, Xinjiang. Positive productswere validated by detecting BDV p40 segment and plasmid to preclude the contamination, andwere sequenced to analyze the homology of gene sequence, amino acid sequence andphylogenetic tree. Results The positive rates of BDV infection in PBMCs of 518 Yili horsesand 206 Yili donkeys were 0.97% and 1.94%, respectively. The results of BDV p40 segmentverification were positive in all of the samples of BDV p24 positive. All the samplestested were not contaminated by plasmid. There was a homology of the gene sequence ofpositive PCR samples with strain He/80. And the gene sequence revealed more than 93%identical to H1766 and strain V. Conclusion Our study suggested BDV natural infection inYili horses and Yili donkeys. The en- demic BDV had a high degree of identity to strainHe/80.