Question: when is a medium sized dog considered a senior
Answer: According to the UC Davis Book of Dogs , small - breed dogs ( such as small terriers ) become geriatric at about 11 years ; medium - breed dogs ( such as larger spaniels ) at 10 years ; large - breed dogs ( such as German Shepherd Dogs ) at 8 years ; and giant - breed dogs ( such as Great Danes ) at 7 years .