1 1/2 Cups seems like a lot of food to expect a yorkie to eat everyday. My little guy is 4.5lbs and 12 weeks, (he's a big puppy!

) and I give him as much kibble as he wants and he still only eats about 1/2 cup a day. If he is eating alot less than that I would be concerned as well. Many dogs, especially yorkies it seems!, are extremely picky eaters. Most owners have to switch foods many times to find something their dog will eat, or have to mix things in there to entice them to eat.
If you are concerned that he is not eating at all, then I recommend mixing in something, like cottage cheese, veggies, boiled chicken, just to get something in his tummy so he won't get sick. Good luck hope something works.
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