Hello I was just wondering I have a dog is an american pitbull terrier but he doesn't gain weight I already used redcell to see if that would help but it doesn't I mean he does gain weight but his body doesn't change he looks the same but heavier so I would like to know if any one knows how to make him gain weight and for him to look bigger . Some people says that is because I make him do a lot of exercise but I guess that is not the reason and I checked him for all type of worms and he is clean I would really appreciate it if someone could help me