Off-campus South Dakota State University users: To download campus access theses, please use the following link to log into our proxy server with your South Dakota State University ID and password.

Non-South Dakota State University users: Please talk to your librarian about requesting this thesis through interlibrary loan.

Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Veterinary and Biomedical Sciences

First Advisor

Christopher C.L. Chase


Epizootic hemorrhagic disease (EHD) is an arthropod-borne viral disease that is transmitted through Culicoides sp. This is the first report of an outbreak of EHD in a wide geographic region of the upper Midwest that involved at least 80 different farms. Herds affected had a wide range of disease from no signs, minor hemorrhaging of mouth, udder erythmea, swelling of coronary bands, lameness to reports of mortality, yet

however approximately for every 100 cow/calf pair there was 3 clinical EHD infections. Findings from both the phone survey and serological studies reinforced that the age of cow could be dependent factor for both symptoms of EHD and seroconversion. Other factors that showed a strong possibly in aiding the spread of EHDV is temperatures both spring and summer, biosecurity practices of cattle producers, co-mingling between cattle and white-tailed deer, and vector control. Further studies are needed as the number of Orbivirus infections increase and the range of the serotypes are spreading in the US. Orbiviruses continue to pose a risk to the cattle industry through trade barriers but also now through the occurrence of clinical disease.

Library of Congress Subject Headings

Cattle--Virus diseases--South Dakota
Hemorrhagic diseases
Communicable diseases in animals


Includes bibliographical references



Number of Pages



South Dakota State University


In Copyright - Educational Use Permitted