Royal Canin Hair and Skin contains targeted nutrients for a shiny coat and healthy skin. Soya and borage oils ,very rich in gamma linolenic acid plus fish oil ,rich in omega 3 fatty acids help make the coat even glossier. The combined supply of amino acids, vitamin B, zinc and copper nourishes the coat and skin, by stimulating keratin synthesis. The coats gets significantly glossier after 21 days of exclusive feeding of Hair and Skin 33.