Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 22, 1997
Publication Date: N/A
Interpretive Summary: Bovine viral diarrhea virus (BVDV) is a prevalent viral pathogen of cattle in the United States. This virus causes a variety of diseases in cattle that range from very mild to fatal. Reproductive failure characterized by reduced fertility, abortion, and birth of weak or deformed calves is an important problem associated with BVDV infection of the bovine fetus. Recently, a second group of BVDV, termed type 2, was identified in the United States. Type 2 BVDV may cause very severe disease and abnormally high rates of reproductive failure in cattle. We tested fetal bovine serum obtained in the midwestern United States for contamination with BVDV. Identification of BVDV in fetal bovine serum would indicate infection of the fetus. We found that greater than 10% of bovine fetuses had been infected with BVDV. Further, we found that type 2 BVDV represented about one third of the BVDV identified in fetal bovine serum. This indicates that the type 2 BVDV have become widespread. This information is important to veterinarians and cattle producers because type 2 BVDV pose a significant threat to beef and dairy herds.
Technical Abstract: One thousand lots of pooled fetal bovine serum were tested for contamination with bovine viral diarrhea virus and/or for contamination with neutralizing antibody against bovine viral diarrhea virus. Noncytopathic or cytopathic bovine viral diarrhea virus was isolated from 203 lots of fetal bovine serum. Analysis of the viral isolates identified 115 type 1 and 65 type 2 bovine viral diarrhea viruses. An additional 23 viral isolates were mixtures of two or more bovine viral diarrhea viruses and were not classified to viral genotype. Further characterization of the type 1 viruses identified 51 subgenotype 1a and 64 subgenotype 1b bovine viral diarrhea viruses. Viral neutralizing antibody was detected in 113 lots of fetal bovine serum. Differential viral neutralization indicated that type 1 bovine viral diarrhea virus induced the antibody detected in 48 lots of fetal bovine serum and type 2 bovine viral diarrhea virus induced the antibody detected in 16 lots of fetal bovine serum.