With an estimated 116 million working equids throughout the world supporting approximately 600 million people, donkeys remain a critical component of human development when used for farming and transportation of goods. Despite their important role in agriculture and human industry, very little is known about donkey health and disease. Liver disease is suggested to be a major contributor to donkey morbidity and mortality, but research on this topic is nearly nonexistent. We hypothesize that liver disease represents a major cause of morbidity and mortality in donkeys in the United States, and that viral hepatitis is a major contributor to the development of liver fibrosis in donkeys.

To test this hypothesis, the following specific aims are proposed. In Aim 1, we will assess the prevalence of hepatitis as a proportion of disease burden in donkeys through retrospective medical record review and will characterize the pathological features of liver disease in donkeys using histopathology of archived liver tissue. In Aim 2, we will investigate the potential role that hepatotropic viruses might play in the development of liver disease using a combination of qPCR, luciferase immunoprecipitation serology assays, and in situ hybridization to assess for viral infection in serum samples and formalin-fixed, paraffin-embedded tissue. For all aims, many of the necessary samples are already available at Cornell University through archived samples collected from previous studies or as submission for routine diagnostics. Additional samples will be available through
collaborations with partners across the United States.

The research in our proposal will advance our knowledge on the role of liver disease in the health of donkeys in North America, which is critical for clinicians and diagnosticians to accurately diagnose disease and initiate appropriate therapies. These proposed experiments will also provide the preliminary needed to apply for federal funding.