I have a lots of dogs and of course of loved them. My Casey died last year and I miss her so much. The dog I miss most was a Belgian Sheppard mix who looks alot like your dog. I still dream about her and it's been 25 years! One night I got out of bed and told my daughter to go and let Tapi in, she was scratching at the screen door! Of course Tapi died before my daughter was born.

With some luck even a big dog will do well until 15 years or so. Then it seems to be arthritis etc. So you are right, lots of excercise and it's really important not to let your dog get overweight. Just like us. She is lovely.