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  I once bought a puppy that I was told was 8 weeks old (not a yorkie) and she was doing the same thing. Went to one vet who really couldn't give me any answers. Got a second opinion and found out that the puppy was most likely not 8 weeks more like 4 to 5 weeks and wasn't developed enough to handle her current diet. She was put on straight puppy formula diet and no food for a few weeks and then I was able  gradually introduce a special food very slowly.  |