Shih Tzu 24 dry dog food by Royal Canin is made for the special needs/physiology of the Shih Tzu breed. L-cystine and methionine (essential for renewing the haircoat) combine with linoleic acid to promote a glossy coat. The kibbles have a special texture that produces a brushing effect, reducing dental plaque formation. According to Royal Canin, special chelating agents slow tartar development by fixing the calcium present in the saliva.