Jester is 14 this year. He doesn't see or hear all that well any more, but he is still the same dog in many ways. He has always been an extremely energetic dog, with a lot of heart, and he still is, on the inside, but despite the fact that neither he nor I want to admit it, he is finally getting old. In the past month he has developed weakness in his hind legs and is unsteady on his feet some of the time. In the early morning (5AM) when we first get up he seems fine, and demands his fetch play as always. I throw the toy less far these days and make him stop sooner, but he moves just fine when he is fetching. Later in the day he becomes weaker, and sometimes when he is standing still he just sort of collapses slowly to the ground and I have to help him up. He also staggers into things occasionally, but not often. I can manipulate his hind legs and he doesn't indicate any pain, but he has always been a very stoic dog so I can't be certain there isn't any at all.
My question: If this were your dog would you go have a bunch of tests run on him, or would you just figure that it is a result of his age and probably nothing could be done? His appetite is normal and his attitude is as good as always.