Submitted to: American Association of Veterinary Laboratory Diagnosticians
Publication Type: Abstract Only
Publication Acceptance Date: 8/18/2000
Publication Date: 10/21/2000
Citation: Fulton, R.W., Saliki, J.T., Confer, W., Burge, L.J., Purdy, C.W., Briggs, R.E., Duff, G.C., Loan, R.W. 2000. Bovine viral diarrhea virus infections in calves from auction markets and a ranch [abstract]. In: Abstract of American Association of Veterinary Laboratory Diagnosticians, 43rd Annual Meeting, October 19-22, 2000, Birmingham, Alabama. p. 34.
Technical Abstract: The objective of the study was to determine the prevalence of bovine viral diarrhea virus (BVDV) persistently infected (PI) calves and infected calves. The calves were purchased from local auctions in east Tennessee (121) and transported to an experimental feedlot in Clayton, NM where they were mixed with calves from a New Mexico ranch (84). All calves were vaccinated at day 0 with a monovalent vaccine containing modified live virus (MLV) infectious bovine rhinotracheitis virus (IBRV) vaccine The New Mexico ranch calves had previously received one dose of parenteral vaccine containing IBRV, bovine viral diarrhea virus (BVDV), parainfluenza-3 virus (PI-3V), and bovine respiratory syncytial virus (BRSV). Sera, EDTA blood samples for peripheral blood leukocytes (PBL), and nasal swabs (NS) were collected weekly from day 0 through day 35, and when the calves were treated. Lung samples from calves dying in the stud) were examined microscopically for lesions and viruses by cell culture inoculation During the study, 152/205 (67.6%) calves were treated for illness associated with acute respiratory disease, and 4/205 (1.8°/o) calves died. There were differences in the morbidity between the Tennessee, 99/121 (81.8%), calves and the New Mexico. 53/84 (63 1%) calves. For sera from 201 surviving calves, 78 (38.8%) seroconverted to BVDV. With only one exception, the type 1 titers in seroconverting calves were greater. There were 60/117 (51.3%) Tennessee and 18/84 (21 4%) New Mexico calves seroconverting to BVDVI. Seroconversions occurred to both BRSV and PI-3V. One calf was BVDV PI, with repeated positive samples from NS and PBL collections while remaining seronegative to BVDV 1 and 2. At least 8 animals were BVDV positive in the NS and/or PBL. BVDV positive cattle were primarily detected in the treated group. Five calves were IBRV positive in the NS within 2 weeks of MLV vaccination. Additional viral isolates, from the NS or PBL, included PI-3V and a bovine adenovirus. BVDV was isolated from one of the 4 lung samples from calves dying in the study. Pasteurella spp. were isolated also from diseased animals and lungs. The study results underscore the involvement of several viruses plus Pasteurella spp. in acute respiratory diseases of cattle. Also, viruses such as IBRV may be found in NS, even in vaccinated cattle. The study also suggests that BVDV vaccination should be considered in infectious disease control programs under these management conditions.