A seven-year-old spayed female mixed breed dog (Goldendoodle) was referred to the Cornell University Hospital for Animals Neurology Service for further evaluation of anisocoria, megaesophagus and a several month history of progressive lethargy. Despite no history of regurgitation, radiographs confirmed the presence of persistent megaesophagus with no evidence of aspiration pneumonia. A presumptive diagnosis of neosporosis was made based on an elevated titer and the presence of multifocal neurological disease. The patient’s demeanor has improved with antimicrobial treatment, and she remains non-clinical for megaesophagus. The pathogenesis of neosporosis and the relationship between Neospora and megaesophagus are discussed. Keywords: Neospora caninum, neosporosis, megaesophagus