Seroprevalence of Bovine Viral Diarrhea Virus (BVDV) in U.S. Alpacas

by Julie Ann Jarvinen, DVM, PhD

JA Jarvinen PhD, DVM, Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA 50011-1250 USA

The following presentation was made at the IV World Camelid Congress in Santa Maria, Catamarca Argentina on October 13, 2006.

BVDV has emerged as a significant pathogen in alpacas in North America where persistently infected crias have been documented. To assess the extent of BVDV infection/exposure in the US national herd, a serologic survey was initiated in April 2006. A request to participate in the study was mailed to 550 randomly selected herd owners representing approximately 10% of herds per state. Participants were asked to submit blood samples from up to five alpacas in their herd between April 1 and July 31, 2006, for testing in a virus neutralization assay. Preliminary results available as of 7-15-06 indicate samples were received from 27 herds in 17 states; five herds (18.5%) in three states (MI, NM and NY) had seropositive alpacas. Of 132 samples from individual alpacas, 12 (9.1%) had titers against BVDV Type I and/or Type 2. In positive herds, from 20 to 80% of alpacas tested were seropositive; BVDV Type 1 titers ranged from 2 to 1024 while Type 2 titers ranged from <2 to 128. Although all positive alpacas were huacayas, only 16.7% of all alpacas sampled were sun. Seropositive animals ranged from 8 months to 9 years of age. Cattle were present on 1/5 farms (20%) with seropositive herds and 2/22 farms (9.1%) with seronegative herds.