|GIVENS, M DANIEL|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2006
Publication Date: N/A
Technical Abstract: Bovine viral diarrhea virus (BVDV) is an important pestivirus that affects cattle throughout the world. Persistently infected (PI) cattle are the most important reservoir for BVDV and shed virus throughout their life. Detecting and removing PI cattle is the key to control and eventual eradication of BVDV. There are many tests available to detect BVDV in PI cattle, including virus isolation, PCR, a commercial antigen-capture ELISA (ACE), and immnohistochemistry (IHC). The most widely used tests to identify PI cattle in the United States are ACE and IHC. Both tests use a monoclonal antibody, 15c5 or 3.12F1, to detect the E**rns envelope glycoprotein, which is thought to be highly conserved among all BVDV isolates. However, a recently identified viral isolate, AU501, demonstrates that not all viral field strains are detected by IHC and ACE. AU501 exhibits a unique mutation at nucleotide position 1330 that results in substitution of an aromatic amino acid, phenylalanine, for an aliphatic amino acid, leucine, at amino acid position 315 within the E**rns glycoprotein. This mutation is associated with lack of detection by IHC and ACE of this field strain which can be detected by virus isolation and PCR. An alternative IHC protocol was developed using cryostat preservation to detect the viral antigen in ear notches from the PI calf. The protocol used a monoclonal antibody, D89, which targets the E2 envelope glycoprotein. This novel protocol was successful in detecting the mutated field strain in frozen ear notches from the PI calf.