TVMDL offers a range of tests to detect bovine viral diarrhea virus (BVDV). BVDV threatens the global cattle industry and negatively impacts producers in the form of decreased or lost productivity.
Despite vaccines and an array of diagnostic tests, this expensive disease continues to impact cattle producers. About 70 to 90% of all infections go undetected, leaving the industry open to more losses from BVDV.
The respiratory, immune, intestinal, blood and reproductive systems can all be affected by BVDV. Diagnosing the disease can require more than one test to determine the cause of a poor doing cow’s symptoms.
Clinical Signs
A BVDV-infected animal can manifest a variety of clinical signs. These include fever, lethargy, loss of appetite, ocular and/or nasal discharge, oral lesions, diarrhea, decreased milk production, abortion, and weak calves that fail to thrive.
Often, there are no outward signs that the animal is infected with BVDV and many diseases present as co-infections with BVDV as the root cause:
- bovine herpesvirus 1 (IBR)
- parainfluenza virus 3
- bovine coronavirus
- pasteurella
- mycoplasma
- histophilus
Testing Guidance
Within the U.S. cattle population, there are three major subtypes of BVD: BVDV 1a, BVDV 1b, and BVDV 2, with the BVDV 1b subtype being the most predominant. The disease is primarily maintained and spread by persistently infected (PI) animals; therefore, most control programs are designed to identify PI animals.
Working with a veterinarian, producers can determine the appropriate test based on an animal’s symptoms. Once it is determined that cattle are infected with BVDV, it is best to consult a veterinarian for recommended disease management options.
Virology or Molecular Diagnostics Testing
| Condition | Sample Type | Methodology |
|---|---|---|
| Persistently Infected (PI) | Fresh ear notches packaged separately | Pooled rtPCR + Antigen Capture ELISA for all samples in a positive pool |
| Fresh ear notch or serum (animal > 3 months old) | Antigen Capture ELISA | |
| Fresh ear notch, serum (animal > 3 months old), or EDTA blood | Virus Isolation (VI) | |
| Ear notch, semen, or EDTA blood | rtPCR | |
| Mucosal Disease | EDTA blood, spleen, intestine, or Peyer’s patches | VI and/or Histopathology |
| Abortion or Still Birth | Fetal lung, spleen, or abomasal contents | rtPCR or VI |
| Respiratory | Live: nasal and conjunctival Dacron swabs Dead: lung or spleen | rtPCR or VI |
| Enteric | Live: rectal swab or feces/ Dead: intestine, spleen, or mesenteric lymph nodes | rtPCR or VI |
Serology Testing
| Condition | Sample Type | Methodology |
|---|---|---|
| Live Animals | Paired serum samples collected ~14-21 days apart, 8-10 animals from a herd | Virus Neutralization (VN) |
| Still Birth or Abortion | Fetal blood, pericardial or pleural fluid Dam: serum | Antigen Capture ELISA and/or VN |