What are you feeding her?
I know that Yorkies can be picky. Bailey went through that when she was younger - probably too many treats from training and not-that interesting of food. I tried kibble, canned, toppings - nothing worked.
I finally took my mom's advice and prepared a nutritionally balanced homemade raw diet. It was the BEST thing that I could have ever done. Bailey now loves, loves, loves her food. We serve hamburger, ground turkey, cottage cheese, rice, eggs, sardines and a vegetable all mixed together.
It can seem like a pain in the butt at first - but I make up several batches and freeze ahead in 10 oz containers. I make enough to last three months at a time.
PM me if you'd like the complete recipe.
Good luck!
BTW - sausage - not so good.
