Because of the current unsatisfactory options for the treatment of MSUD, there is a need for improved therapies to combat this disease. An obstacle to developing novel treatments for MSUD has been the lack of a suitable animal model to perform necessary preclinical studies. Although a Hereford calf model with MSUD has been described [17-19], this model is neither readily available nor practical to perform preclinical studies. Furthermore, comparison of this animal model with human MSUD has shown some differences in the pathology of the disease [1], making this animal a less desirable model for the human disease.