| You really need to take him to the vet and have him checked out. Good luck, its so good when people adopt adult dogs from the shelters. He may have a stomach upset, or have caught a virus , the stress of being in a shelter and on cold concrete floors which a lot of them have, means many dogs get digestive problems or pick up viruses because of compromised immune systems from the changes, the stress, and I know some of our local government shelters keep those poor dogs locked outside all day on the cold concrete, no blankets or anything, even in damp, cool weather, until its really, really cold. No wonder some of them get sick. Good luck with him. | 
