We had a farm dog bitsa made it to about 18, aussie terror - 16ish, ACD 17.

I have a friend with a very healthy and energetic boxer who is 9.

And there is a rather ancient GSD that visits who is 13+ Sometimes gets rude comments about how wobbly he is at the back end and shouldn't breed dogs like that and then I tell the rude person how old the dog is and they shut up.