Duurstede shampoo is too expensive and over rated. There are a few human grade shampoos that do seem to work really well on a Yorkie coat. When I went to watch the Yorkies at the dog show, there was a trainer there I got to talk with about grooming and such. She was showing a beautiful male and his coat was amazing. She uses Neutrogena CLEAN Replenishing moisturizing shampoo. It's in a clear bottle and the shampoo is pink.
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