We have a 10+yr old lab who is doing awesome, but def. slowing down. He runs w/my DH & it is his fave thing in the world (it's by a lake, so he gets to swim too) but over the next couple of years that's going to decline for sure. Of course you can't run a new pup right away either, so part of me wants to get a new one in the next year or so & ramp him up while the old guy starts to slow down.
Of course it's not all about the exercise- our old guy is about as close to perfect as you can get in his behavior, so we've been told by many people we should get a new one & he will help "teach" by modeling such good behavior. Experience or truth in that? We also have kids & I think that it would help to have another one when ours passes because it will help w/the empty hole in our family.
My DH isn't sure he wants to get a new one while ours is still around- he thinks it will seem like we're trying to take his place & that ours will hate it. He isn't a dog who really loves other dogs- he's kind of indifferent. He thinks he's a people Anyway, just really mulling this over & seeing if anyone has some sage advice. We always said we'd get a new pup when he was 10- that time went way too fast & now we're not sure!