I feed my yorkie Royal Canine for Yorkies. It states that they make the food especially for yorkies. It is suppose to help with their teeth, hair, and skin. I think it's the best. I also give him salmon oil. I also give hime one boiled egg a week also for his hair. Petco sell dried salmon for dogs also. My Man loves it. The dried salmon can be grated over the food as well. If any of you have a problem with your yorkie eating, there is a dog food Made By Merricks(can food). It has real chicken thighs and wings with carrrots,blueberries,apples and all other sort of good natural foods. The brand is sold by Petland. Its not sold at Petco. You can also check out the web site
Merrick Pet Foods if you like.