The world leader in serving science Sensitivity and specificity of multiple technologies for the detection of confirmed persistently BVDV infected cattle from a feed yard in South Texas Lalitha Peddireddi 1 , Richard Hesse 1 , Gregg Hanzlicek 1 , Jeff Baxter 2 , Ivan Leyva-Baca 2 1 Kansas State Veterinary Diagnostic Laboratory, Kansas State University, 2005 Research Park Circle Manhattan, KS 66506 2 Animal Health Group at Thermo Fisher Scientific, 2130 Woodward St, Austin, TX 78744, USA
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Sensitivity and specificity of multiple technologies for ... · Etiology: Bovine Viral Diarrhea Virus ... NCP account for 95% of the isolated BVDV • cytopathogenic (cp): induces
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The world leader in serving science
Sensitivity and specificity of multiple technologies for the detection of confirmed persistently BVDV infected cattle from a feed yard in South Texas Lalitha Peddireddi1, Richard Hesse1, Gregg Hanzlicek1, Jeff Baxter2, Ivan Leyva-Baca2
1Kansas State Veterinary Diagnostic Laboratory, Kansas State University, 2005 Research Park Circle Manhattan, KS 66506 2Animal Health Group at Thermo Fisher Scientific, 2130 Woodward St, Austin, TX 78744, USA
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Etiology: Bovine Viral Diarrhea Virus (BVDV) Etiology: Bovine Viral Diarrhea Virus (BVDV) is an pathogen that belongs to the genus Pestivirus of
the family Flaviviridae
BVDV is an enveloped, single stranded RNA virus
Economic Relevance: Bovine Viral Diarrhea leads to major economic loss in both beef and dairy
industries estimated to be ~ $2-3 billion annually in the US alone
History: It was first reported in 1946 in Ithaca New York by researchers from Cornell University in
one-cow herd with subsequent outbreaks of the disease with morbidity 33-88% and mortality of 4-8%
Genome: Has a positive sense single stranded RNA genome (ss (+) RNA). Size of approximately
12.3 Kb. The genomic RNA has one open reading frame of about 4000 codons flanked with 2 untranslated regions (5’- and 3’-UTR)
Vet. Res. 41 (6) 44 (2010)
DOI: 10.1051/vetres/2010016
This is an Open Access article distributed under the terms of the
• Prevalence of seropositive cattle varies among countries and is influenced by vaccine use and management practices
• In USA, seropositive rates range between 40 and 90%
• Unvaccinated herd-level prevalence with unvaccinated cattle varies from 28 to 53% depending on the region
• PI prevalence is ~0.2% in the USA
Epidemiology:
• From an epidemiological point of view BVDV is very talented
• It has a combination of strategies to remain in a herd for extended periods of time
• Persistent infection provides a unique ability to BVDV to survive by inducing immune tolerance trough evasion of both innate and acquired immunity in utero
• Laboratory techniques are the best way to detect the presence of BVDV and distinguish the form of the disease
Rationale: There was a request from the Kansas Farm Bureau in South East Kansas to regulate
BVDV in their region by making it a reportable disease. SNAP BVDV Antigen Test was getting
some discrepant results when compared to testing in VDLs
• The application of highly sensitive and specific diagnostic technologies is fundamental to
accurately identify those low prevalent PI-BVDV animals for implementation of control strategies
Objective: To compare the sensitivity and specificity performance of:
BVDV Test Methods
Immunochromatographic strip
Antigen Capture ELISA
Applied Biosystems RT-PCR VetMAXTM Gold BVDV PI Detection Kit
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Materials and Methods
• Two samplings with three weeks apart of previously confirmed PI-BVDV (n=37) and BVDV-negative (n=20) cattle were performed from a feed yard located in South Texas, USA holding 24,000 cattle and keeping PI-BVDV in a single pen until slaughter time (~n=48)
• During the first sampling five ear notches from each animal were collected in a single day shipped out overnight to the Kansas State Veterinary Diagnostic Laboratory (KSVDL) in order to be processed immediately after arrival with the following diagnostic technologies:
• Two weeks later, resampling of the same set of animals (n=57) was carried out to be tested with IHC and BVDV RNA sequencing as the gold standard methods
• True positive or true negative based on the combined results from at least 1 out of the 2 methods was implemented
Table 1. Result of the real-time PCR testing, SNAP test and Antigen Capture ELISA
Gold standard/Tested technology
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Discussion and Conclusions
• All of the diagnostic technologies tested in this study offered a good but different level of sensitivity and equal level of specificity
• However, the real-time PCR technology tested was more sensitive than the antibody-based methods
• The practical implication of using diagnostic technologies with low sensitivity e.g. (91.67% and 94.44%) with a disease of very low prevalence (0.2%-0.4%) such as PI-BVDV in the US is of significant importance
SNAP Test ACE VetMAXTM Gold BVDV PI Detection Kit
• The current study reveals substantial practical differences in diagnostic methods that can be used as management tools in controlling BVDV and ultimately reducing the incidence of BRD.
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Acknowledgments
• KSVDL
• South Texas Feed Yard
• Thermo Fisher Scientific
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