Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/7/2011
Publication Date: 3/1/2012
Citation: Hessman, B.E., Sjeklocha, D.B., Fulton, R.W., Ridpath, J.F., Johnson, B.J., McElroy, D.R. 2012. Acute bovine viral diarrhea associated with extensive mucosal lesions, high morbidity, and mortality in a commercial feedlot. Journal of Veterinary Diagnostic Investigation. 24(2):397-404. Interpretive Summary: Infection with bovine viral diarrhea viruses (BVDV) can result in a wide range of different symptoms. In this study, a symptom, mouth lesions, not commonly associated with BVDV, was observed in feedlot animals that had BVDV infections. Observation of lesions in the mouth is associated with a number of different diseases, including foot-and-mouth disease (FMD). Because FMD is listed as a high consequence pathogen for animals in the United States, observation of mouth lesions always raises concerns. For this reason, diagnosticians want to identify the pathogen-causing mouth lesions as quickly as possible. The value of this study is that it demonstrates that BVDV may cause mouth lesions. This indicates that BVDV should be included in the panel of pathogens for which diagnosticians test when mouth lesions are observed.
Technical Abstract: In 2008, a northwest Texas feedlot underwent an outbreak of bovine viral diarrhea virus (BVDV) disease causing high morbidity and mortality involving two lots of calves (Lots A and B). Severe mucosal surface lesions were observed grossly in the oral cavity, larynx and esophagus. Mucosal lesions varied from small (1-3 mm) infrequent mucosal ulcerations to large (5mm-1cm) and coalescing ulcerations. Necrotic debris was present in ulcerations of some mortalities with some having plaque-like debris but other mortalities presented more proliferative lesions. A calf persistently infected with BVDV arrived with one lot and the isolated virus was genotyped as BVDV1b. Identical BVDV1b strains were isolated from two other mortalities. A BVDV2a genotype was also isolated in this outbreak. This genotype was identical with all BVDV2a strains isolated in both lots. Serum samples were collected from exposed and unexposed animals and tested for antibodies for multiple viral pathogens. Seropositivity ranged from zero% for Calcivirus to 100% positive to pseudocowpox virus. At the end of the feeding period the morbidity and mortality for the two lots involved was 76.2% and 30.8%, respectively, for lot A, and 49.0% and 5.6% for lot B. Differential diagnoses included vesicular stomatitis, bovine papular stomatitis, and foot-and-mouth disease virus. Based on this case, acute BVDV disease should be considered when mucosal lesions are observed grossly.