Pain or anxiety.

Has he been to the vet yet to rule out any medical issues?

If this is anxiety, long walks on lead will help. Lots of exercise, lots of structure. Being with him all the time will not help his anxiety - (but agree that of course he should never be alone outdoors!)

I would get him to the vet for starters, then start alone training after you know that he is healthy.

Panting can be a sign of Cushings. I'd get him to a vet.

Sounds like the panting could be a sign of pain (his hips mentioned earlier). My Lab was panting- this was the first sign of the cancer we lost him to in May. He was still active, eating,and chasing squirrels around the yard. Dogs can mask pain very well. The panting was a red flag. My vet says it is a very common sign of pain. Take your new dog to the vet asap. Hopefully it is nothing serious.

Why do you keep adopting when you cant take care of them???

Christine, I don't understand the question. This is the first older (10 mos.) dog we have ever adopted. All of our former dogs for the last 50 years came into our home as puppies. The cats are here because we live on a farm and people seem to think we really want their drop-offs. They are all neutered/spayed and the latest kittens will get their 'alterations' done in a few weeks.

Maybe you are thinking of someone else. I know that can happen with so many posters.