Pigeon Fever is a seasonal disease in horses caused by the Gram positive bacterium Corynebacterium pseudotuberculosis. The bacterium produces an exotoxin, Phospholipase D (PLD), which provokes both internal and external manifestations of the disease in horses. The disease is poorly understood and there has been little progress in developing a vaccine for equids. In evaluating the equine immune response to Corynebacterium pseudotuberculosis, a mouse model was employed in the hope of developing a test that would allow for rapid detection of PLD in horse blood. Said field assay could be used to determine ?at risk? farms where an infection would likely manifest itself. Murine hybridoma cells were generated and characterized. They were then subcloned by limiting dilution to ensure that all cell lines were monoclonal. All characterization and subcloning experiments utilized an Enzyme Linked Immunosorbent Assay (ELISA) to measure antibody production. While the majority of the monoclonal antibodies were of the class IgG, some were found to be of the class IgM. No hybridoma lines were characterized as IgA. The establishment of the murine model has also provided excellent tools to help us better understand the antigenic nature of PLD for application in subsequent ELISA procedures.