avian & livestock assay data sheet

Bovine viral diarrhea virus (BVDV)

Test code: S0141 - Ultrasensitive qualitative detection of bovine viral diarrhea (BVD) virus by reverse transcription coupled real time PCR

Bovine viral diarrhea virus (BVDV) is a single-stranded positive-sense RNA virus classified as a pestivirus belonging to the Flaviviridae family. Infection of cattle with this disease can pose severe economic losses to the dairy and beef industries, primarily due to decreased reproductive performance. BVDV occurs nearly worldwide.

Two major BVDV strains have been identified, designated as genotype 1 or genotype 2 on the basis of antigenic variation and differences in sequences in the 5' UTR of the viral genome. Infection by different strains of BVDV can have different clinical symptoms. Infected cattle may develop gastrointestinal disease, immunosuppression with secondary infections, thrombocytopenia and reproductive failure. In infected pregnant cows, the virus is transmitted to a fetus with a high degree of efficiency, leading to fetal loss, malformations or birth of a persistently infected calf.

Fetal infection with BVDV may result in the birth of a calf immunotolerant to BVDV, with an inapparent persistent infection. These calves can become carriers and remain viremic throughout their lifetimes, shedding infectious BVDV and acting as reservoirs of the virus in cattle herds.

Serology testing is not effective for identifying viremic, immunotolerant calves.  Serology testing is also not very useful for testing pooled serum samples because of its low sensitivity. On the other hand, molecular detection of the virus by PCR is a rapid, specific, sensitive and cost effective method for identifying viremic individuals (Weinstock, et al., 2001).

Utilities:

• Confirm the disease causing agent
• Identify BVD carriers
• Ensure that animal herds and populations are free of BVD
• Early prevention of spread of the virus among animals
• Minimize human exposure to the virus
• Safety monitoring of biological products that derive from animals

Specimen requirements: 0.5 ml feces, or 0.5 ml whole blood in EDTA (purple top) or ACD (yellow top) tube, or 0.5 ml serum, or 0.5 ml tissue.

For specimen types other than those listed here, please call to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative reverse transcription coupled real time PCR

Normal range: Nondetected