Submitted to: Canadian Veterinary Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/24/2010
Publication Date: 3/20/2011
Citation: Byers, S.R., Evermann, J.F., Bradway, D.S., Grimm, A.L., Ridpath, J.F., Parish, S.M., Tibary, A., Barrington, G.M. 2011. The effects of exposure of susceptible alpacas to alpacas persistently infected with bovine viral diarrhea virus. Canadian Veterinary Journal. 52(3):263-271. Interpretive Summary: Bovine viral diarrhea virus (BVDV) infections are a source of major economic loss to producers worldwide. When BVDV infect pregnant animals, the resulting offspring may be born with life long viral infections, also known as persistent infections. Persistently infected (PI) animals infect other animals with which they have contact. These viruses not only infect cattle, but a number of other hoofed animals, such as sheep, goats, buffalo, and deer. Recently persistent BVDV infections in alpaca have been reported. The goal of this research was to see if contact with PI alpacas would cause other alpacas to become infected with BVDV. It was demonstrated that PI alpacas transmitted BVDV to pen mates. This research illustrates why the alpaca industry should develop strategies to detect and eliminate PI alpacas.
Technical Abstract: Reports of bovine viral diarrhea virus (BVDV) infections in alpacas have been increasing over the past several years but much is still unknown about the mechanisms of disease in this species. This report describes research performed to characterize the transmission of BVDV from persistently infected (PI) alpacas to BVDV naïve alpacas, document shedding patterns, and characterize the disease effects in both PI and transiently infected alpacas. Two PI alpacas were determined to shed BVDV Type 1b virus in most body fluids, and commonly available diagnostic tests were used to verify their status. Bovine viral diarrhea virus Type 1b transient infections produced only mild signs of disease in BVDV naïve alpacas. Viremia was detected on whole blood samples, however, viral shedding during the acute phase was not detected and antibody appeared to be protective upon re-exposure to the virus.