First Isolation and Genomic Characterization of BVDV-1c in Przewalski's Gazelle (Procapra przewalskii) from the Qinghai-Tibet Plateau, China.

Przewalski's gazelle (Procapra przewalskii) is an endangered ungulate endemic to the Qinghai-Tibet Plateau of China. Increasing habitat alteration and close contact with domestic livestock have raised concerns about cross-species pathogen transmission, yet infectious disease studies in this species remain limited. To determine the etiology of illness in two deceased gazelles from a conservation facility in Qinghai Province, we screened samples for a panel of pathogens, including Mycoplasma ovipneumoniae, Clostridium perfringens toxin genes, Mannheimia haemolytica, Klebsiella pneumoniae, Mycoplasma capricolum subsp. capripneumoniae, Pasteurella multocida, Peste des petits ruminants virus (PPRV), Bovine viral diarrhea virus (BVDV), and Infectious bovine rhinotracheitis virus (IBRV), using PCR and RT-PCR. BVDV-specific nucleic acids were detected in tissue samples from both individuals, whereas all other targeted pathogens tested negative. The virus was successfully isolated in Madin-Darby Bovine Kidney (MDBK) cells and confirmed by RT-PCR, followed by whole-genome sequencing of the isolate, which was designated QH PSYL 2026. Phylogenetic analysis based on the full-length genome and 5'UTR sequences assigned the isolate to the BVDV-1c subgenotype. Notably, its 5'UTR sequence shared 100% identity with those of local cattle-derived BVDV strains, providing molecular evidence suggestive of an epidemiological linkage between wildlife and livestock. Integrating clinical signs, gross pathology, and laboratory results, the cases were consistent with BVDV infection as the primary presumptive etiology. To our knowledge, this is the first report of BVDV infection, virus isolation, and genomic characterization in Przewalski's gazelle. The detection of a BVDV-1c strain in this endangered species highlights the potential threat that livestock-associated pathogens pose to wildlife on the Qinghai-Tibet Plateau. These findings furnish crucial baseline data for disease surveillance, molecular epidemiology, and conservation management of Przewalski's gazelle and provide valuable scientific evidence for wildlife disease prevention and control in plateau ecosystems.