I have two older male Shelties. Marley is 13 and Dempsey is 10.
Marley was always mellow, but he's really slowed down the last couple of years. He doesn't like the yunguns playing near him, so he has what we call 'the Marley no play zone'. If they get too close he grouses at them. Kisses are okay with him, but no rough play, and they respect that.
He limps when its cold or damp outside, but a buffered asprin fixes that. He also needs dental work, but the vet says hes too old. She refers to him as one of her geriatric patients.
Dempsey has always been hyper and has only slowed down a little. He has arthritis, and even though he limps he still runs around. He just won't do stairs any more and has to be carried up them. He's been taking Rimadyl every day since last spring. ($70 a month!
) It seems to make him more comfortable and less cranky.
All my dogs eat Canidae with Derma Coat food supplement. The only 'vitamin' is the Yogurt Drops they get as a treat.
Overall I guess they're in pretty good health. I just dread the day when they aren't any more. Thats why I can't fathom reading that book about Marley that everyone is raving about.