Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/23/2008
Publication Date: 11/1/2008
Citation: Nelson, D.D., Dark, M.J., Bradway, D.S., Ridpath, J.F., Call, N., Haruna, J., Rurangirwa, F.R., Evermann, J.F. 2008. Evidence for Persistent Bovine Viral Diarrhea Virus Infection in a Captive Mountain Goat (Oreamnos americanus). Journal of Veterinary Diagnostic Investigation. 20(6):752-759. Interpretive Summary: Bovine viral diarrhea viruses (BVDV) have long been recognized as economically important pathogens of cattle. BVDV cause both transient infections (acute) that last on the average 8 to 14 days and long term infections (persistent) that last for the life time of the animal. Persistent infections are the result of exposure during fetal development. Persistently infected animals play a major role in spreading BVDV. Thus in order to reduce production losses associated with BVDV it is important to identify and eliminate persistently infected animals. Originally it was thought that only cattle could become persistently infected with BVDV. It is now known that persistent BVDV infections occur in species other than cattle. Recently research efforts have been aimed at identifying these species. This study reports the first identification of persistent infection in mountain goats. The persistently infected mountain goats were housed in a zoological park in Idaho. This report is significant in that it identifies BVDV persistent infection in a new species and points out the importance of BVDV surveillance in zoo animals.
Technical Abstract: Bovine viral diarrhea viruses (BVDV) are pestiviruses that have been isolated from domestic and wild ruminants, and there is serologic evidence of pestiviral infection in more than 40 species of free-ranging and captive mammals. Vertical transmission can produce persistently infected animals that are immunotolerant of the infecting strain of BVDV and shed virus throughout their lives. Seven species (white-tailed deer, mousedeer, eland, domestic cattle, alpaca, sheep, and pigs) have been definitively identified as persistently infected with BVDV. This study provides serological, molecular, immunohistochemical, and histological evidence for BVDV infection in two captive mountain goats (Oreamnos americanus) from a zoological park in Idaho. The study was triggered by isolation of BVDV from tissues and immunohistochemical identification of viral antigen within lesions of a 7-month old male mountain goat (Goat 1). Blood was collected from other mountain goats and white-tailed and mule deer on the premises for BVDV serum neutralization, viral isolation, and PCR. One 3-month old mountain goat (Goat 2) was antibody negative and BVDV positive in serum samples collected 3 months apart. This goat then died, and though still antibody negative, BVDV was isolated from tissues and identified by immunohistochemistry within lesions. Sequencing and phylogenetic analysis identified the isolates as BVDV 2. These findings provide evidence of persistent infection in a mountain goat, underscoring the need for pestivirus control strategies for wild ruminants in zoological collections.