Will Falconer, DVM Moderator
She was an exceptionally healthy dog, sounds like. One thing I'd posit is that, living back then, animals were fairly "new" to this onslaught of vaccines and poisons, and they still had resilience to their effects.
As we've gone through the past 50 years (roughly 100 generations in dogs), we've seen inherited chronic disease become the norm. The damage done to the ancestors carries forward. That's how I can see exactly what sorts of health challenges I've gotten from each of my parents, and why a human homeopath is so interested in your ancestor's illnesses and cause of death.
I suspect very few could live to 17 today with annual vaccinations, canned food and tick pesticides. And yes, full throttle exercise in her territory helped.