Hello..When I adopted my Chihuahua he was at a weight of 10.2 oz and his old owner had him on supermarket dog food... He's not a long leg dog he had a short body tiny head little ears 10 lbs was to big for such a little dog 3 lb weight loss is allot for a small dog some people just don't what there talking about.My dogs is now at 7.4 lbs my vet said he looks great.. 2 - 3 lb weight loss is big for a Chihuahua..My little guy eats 1/4 dry (Natures Variety).with some raw in his diet some fresh veggies and some fruit found out that he can't handle grains..He get a walk down the street and back up the other side for a Small dog with short little legs that a long walk.. I have had him for 5 1/2 months.. took about 3 months to get the weight off him he did not like to walk...Best of luck with your dog..O his treats are fresh frozen baby carrots fresh frozen green beans some no more dog cookies.last week he went to the vet just for a check up vet said he looked great...He's 4 years old

try chicken and rice meals for older dogssome are strong and bigged bone they will wt more thenmost should be about 5 lbs or under however depends on the frame build of the dog i feed mine a cup.One is a larger size and is 6 or 7 lbsthe other one is about 4 lbs.Dont forget no table foodsthey are both near 10 years oldhowever it last into the next day