However, the systematic application of human AD neuropathological criteria to canine brains has been limited.<h4>Objective</h4>The objective of this study was to apply established human neuropathological criteria (Thal, Braak, and CERAD) to aged canine brains and examine relationships among neuropathology, cognitive status, and plasma biomarkers.<h4>Methods</h4>Postmortem brain tissues from 24 client-owned senior dogs were evaluated using Thal phases for Aβ deposition, Braak-based regional assessment of tau pathology, and CERAD criteria for neuritic plaques. The gene discussed is MAPT; the disease is Alzheimer disease.