this alarms me. in your first posting you yourself are scared as you say you can count ribs and vertebrae. the vet gives you worm pills without doing a fecal. i have heard that sometimes dogs can have worms and it still not show up in the fecal that is collected (dont ask me how or why). did the vet not seem concerned at the dog's weightloss? if a dog is steadily losing weight and their eating/drinking habits have not changed or actually have increased, then there is something medically going on. please dont wait too long to see another vet. if he loses too much weight, it could start affecting his muscles and organs. have you ever thought about feeding raw? this would definately put the weight on him without the growth spurt that sometimes can happen with kibble. raw chicken wings, legs, necks, back, raw ground beef and raw beef rib bones, turkey necks, wings, hearts and gizzards. all of these have the proper calcium/phosorus ratio with easily digested proteins and fats. feed several pounds of this each day and several times a week in addition to the above raw meaty bones, give scrambled eggs, raw liver, rice/oats, steamed and chopped veggies such as squash, pumpkin, peas, carrots, sweet potatoes, etc.
i would also insist on a glucose test to determine if there is diabetes. increased eating and drinking is 2 major signs.
