I am new to this site but would also like to add that a product called Puppy NutriCal is very good for puppies at a young age, especially if you don't know if they are eating or not. Puppies really like that taste of it. I have 2 puppies and give them just a little on my finger every night (eventhough they eat on a norm). It's like multivitamins for the puppies. Maybe you should also try that. You should find it at Petco or Petsmart but make sure that it is for puppies because they do have some for adults and that can be too much for a pup. Good luck! Also added a link to PetSolutions.
http://www.petsolutions.com/default....06785&SID=NXTG