This case report describes the history, clinical presentation, diagnostic assessment, treatment and response to initial treatment of a one-and-a-half-year-old, male, castrated Australian Heeler that presented to Cornell University Hospital for Animals for a four-month history of large-volume steatorrhea and severe weight loss. He presented after a week of acute-onset lethargy, hyporexia, and lameness. The dog was diagnosed with Exocrine Pancreatic Insufficiency (EPI) based on signalment, clinical history , presentation, and a low canine serum Trypsin-Like Immunoreactivity (cTLI). Based on positive exposure to Anaplasma indicated by Idexx 4DX SNAP test, acute Anaplasmosis could not be ruled out as a potential cause for the acute presentation. Therefore, the patient was treated with Doxycycline for potential acute Anaplasmosis, and he was also treated with oral powdered pancreatic enzyme replacement. As of a two months following initiation of treatment, the patient’s clinical signs had resolved, and he had returned to an appropriate body condition.