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Bovine Viral Diarrhea Virus Variability and Prevalence of BVDV Subtypes in Persistently Infected Cattle Entering Feedlots: BVDV1b as Predominant Subtype. Dr. Robert W. Fulton McCasland Foundation Endowed Chair for Food Animal Research Oklahoma State University. B. V. D. V. 1. b. -. N.
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Bovine Viral Diarrhea Virus Variability and Prevalence of BVDV Subtypes in Persistently Infected Cattle Entering Feedlots: BVDV1b as Predominant Subtype Dr. Robert W. Fulton McCasland Foundation Endowed Chair for Food Animal Research Oklahoma State University
B V D V 1 b - N Y - 1 9 5 . 6 % B V D V 1 b - H a s t 9 3 . 5 % B V D V 1 b - T G A N 8 3 . 3 % B V D V 1 a - N A D L 9 7 . 8 % B V D V 1 a - S i n g e r 8 4 . 9 % B V D V 1 a - C 2 4 V B V D V 2 b - V S - 2 6 0 9 4 . 1 % B V D V 2 b - V S - 6 3 9 0 . 2 % B V D V 2 b - S o l d a n 7 9 . B V D V 2 a - 8 9 0 9 3 . 0 % B V D V 2 a - 2 9 6 n c 8 8 . 7 % B V D V 2 a - 1 2 5 n c BVDV Subgenotypes BVDV1b BVDV1a 6 2 . 7 % BVDV2b 2 % BVDV2a Dr. Julia Ridpath, USDA, ARS, NADC
BVDV PI studies: OSU 1999-2009 with BVDV1b • 1999 – PI calf • in retained ownership program entering feedlot. • 1999-2000 –SE US calves to feedlot :BRD • 1999 study: PI calf, BVDV 1b , BRD disease • Nasal swabs, PBL, lung isolates, BVDV1b • Can J Vet Research, 2002, 66: 181-190
BVDV PI studies: OSU 1999-2009 with BVDV1b • 2005- Subtypes in Diagnostic Laboratory Accessions. Vet Microbiology, 2005, 111,35-40 • Subtypes • BVDV1b: 45.8% • BVDV1a: 28.2% • BVDV2a: 26.0% • Categories of Disease : all subtypes involved • Respiratory, digestive, mixed/multiple, abortions • Persistent Infections
BVDV Subtypes in PI Cattle in SW Kansas Feedlot: 2007-2008 • PI cattle: 0.4% 86/21,743 JAVMA , 2006,228: 578-584
BVDV Subtypes in PI Cattle in Oklahoma Feedlot: 2007-2008 • PI cattle: 0.4% 30/7497
BVDV Subtypes in Beef Breeding Herd Study for PI calves : 2006 • 30 herds with 5 herds positive: 16.7% • 25/ 4530 calves as PI= 0.55% • Three herds with single PI and 2 with multiple (10 and 12) • One dam of PI calves: PI (4.0%) • All PI isolates as BVDV1b Can J Vet Res, 2009 in press
>99.9% similarity BVDV1b BVDV PI strains from 2006 NF BPS Survey
Diversity of BVDV Antibodies in Vaccinated Cattle: Two Doses with BVDV1a and 2a strains
Implications of Diversity of BVDV: Diagnostic Tests • Impact on Diagnostic Test for Antigen Detection • Monoclonal selection: epitopes : potential changes in epitope genome region may affect reactivity and diagnosis • IHC and ACE • FA • Viral genome differences for PCR tests
Vaccines Against Multiple BVDV Subtypes • US and Canada : BVDV1a and BVDV2a strains • Demonstrate protection against acute challenge for multiple subtypes, ie BVDV1b • Demonstrate protection against fetal challenge for multiple subtypes, ie BVDV1b • Potential for BVDV1b monovalent or combination with BVDV1a and BVDV2a • Novel vaccines with multiple strains, genomic regions or protein subunits from different strains