My chocolate Lab is about 1 1/2 years old. A couple of months ago he was a good solid 82 pounds and now he is anywhere from 40-50 lbs. I feed him 2 times a day, exercise with him, walk him, let him in the house everything a good owner would do but I don't understand why he is losing weight. Diarrhea is a main concern because he has diarrhea none stop. I had him checked for worms, parvo the whole works but nothing came up. They want me to pay an extra thousand dollars to check him for some other stuff. We have another dog he plays with, they play tug of war, catch everything. I even bought the canned food for him and he is not gaining weight at all. You can see his shoulder blades, his ribs. He is such a gentle, loveable dog, and I definitely know he is not a fighter. I would never let me dogs do it. I trained them not to. Please can someone help me out and figure out what is going on with him. Diabetes and Cancer is the only things to mind. Please any feedback thank you. I will try to put a picture of him on here.