We are fostering a Manchester terroir and this dog is always hungry. We feed him 3/4 cup of premium dog food twice a day. After he eats he is whining a couple of hours later for food. When it gets close to feeding time he whines barks and shakes until he is fed. He also drinks a lot of water. He is a rescue and he is about 8 years old. We have been told he was tested for cushings disease and it was negative. We are concerned about his health. He also has a lot of bowel movements. The bowel movements are solid. We do not want to over feed him. We are concerned there may be another health issue.