It's not age so much as arthur. Tore a cruciate ligament as a 7 year old, his stifle on the left is double the thickness of the right, bit of dysplasia in the hips too. I make him walk twice a day, the 3rd walk he stays home in the evening. He is great for #1, a bit laid back for #2 and #3 he lays there, his eyes say it all. lol.
Switched them over to raw feeding. Going well for the most part.
If you understand, things are just as they are; if you do not understand, things are just as they are.
~ Gensha, Zen Master