|Vander Ley, Brian|
Submitted to: American Journal of Veterinary Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2012
Publication Date: 3/1/2013
Publication URL: http://handle.nal.usda.gov/10113/61367
Citation: Ridpath, J.F., Falkenberg, S.M., Bauermann, F.V., VanderLey, B.L., Do, Y., Flores, E.F., Rodman, D.M., Neill, J.D. 2013. Comparison of acute infection of calves exposed to a high-virulence or low-virulence bovine viral diarrhea virus or a HoBi-like virus. American Journal of Veterinary Research. 74(3):438-442. DOI: 10.2460/ajvr.74.3.438. Interpretive Summary: Infections with bovine viral diarrhea viruses (BVDV) result in significant economic losses for cattle producers in the United States. BVDV infections are associated with respiratory and reproductive disease. Recently, infection with a group of newly recognized viruses, referred to as HoBi-like viruses, has been reported in cattle and water buffalo in South America, Southeast Asia, and Europe. Affected animals developed reproductive or respiratory disease. HoBi-like viruses appear to belong to the same family tree as BVDV but on a separate branch. Thus far, infection with HoBi-like viruses has not been reported in the United States. The purpose of this study was to compare infection of cattle with BVDV strains to infection of cattle with a HoBi-like strain. It was found that the disease that followed infection with the HoBi-like strain while similar was milder than that observed with the BVDV strains. Because the disease was mild there is a question of how quickly introduction of HoBi-like strains into a cattle population would be noted. Having HoBi-like virus strains and BVDV strains circulating at the same time in a cattle population could confuse diagnosticians and hamper BVDV control programs.
Technical Abstract: The objective of this research was to compare clinical presentation following acute infection of cattle with either a high virulence (HV) BVDV or a low virulence (LV) BVDV to clinical presentation following infection with a viral strain that belongs to an emerging species of pestivirus. The viral strain D32/00 HoBi is a member of an emerging species of pestivirus that infects cattle. It is antigenically related to BVDV and classical swine fever virus and has been isolated from water buffalo and/or cattle in South America, Southeast Asia, and Europe. Clinical presentations, in field cases, include reproductive and respiratory disease and persistent infection. It has also been found as a contaminant of fetal bovine serum batches. In this study, infection of colostrum-deprived calves with the D32/00 HoBi strain resulted in a clinical presentation, marked by a decrease in circulating lymphocyte numbers and low grade pyrexia, was milder than that observed with a LV BVDV.