Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/9/2003
Publication Date: 11/9/2003
Citation: Fulton, R.W., Step, D.L., Johnson, B.J., Ridpath, J.F., Saliki, J.T., Confer, A.W., Kellenberger, J.L. 2003. Bovine viral diarrhea virus type 2 persistent infections in BVDV1a and BVDV2 vaccinated breeding herd. Research Workers in Animal Diseases Conference Proceedings. Paper No. 167. Interpretive Summary:
Technical Abstract: Bovine viral diarrhea viruses (BVDV) represent significant pathogens to cattle. Persistently infected (PI) calves represent important reservoirs of infections. Biosecurity to detect and eliminate PI are necessary for control programs in addition to an effective vaccination program to prevent fetal infections. Out of approximately 250 heifers, 31 PI calves and at least 9 more dead calves were identified in the spring 2003. These heifers were ear notch BVDV IHC negative prior to breeding. These heifers had received three doses at weaning; postweaning 2-4 weeks later, and prior to breeding with a MLV vaccine with BVDV1a, BVDV2, PI-3V, BRSV. Five calves, ear notch IHC BVDV positive were necropsied with numerous tissues collected for viral isolation and histopathology. BVDV NCP strains were isolated from serum, PBL, and organ pools of all five calves. The viruses were subtyped by sequencing of the 5'-UTR and differential PCR. These viruses were quite different from reference BVDV2 strains and BVDV2 vaccine strain used in this herd. This study indicates diversity of U.S. BVDV2 strains and that current BVDV2 vaccinal strains may not confer protection against all BVDV2 strains.