The Oxbow Animal Health Natural Science Vitamin C Small Animal Supplement is a hay-based, high-fiber supplement containing the essential stabilized vitamin C that guinea pigs need! The vitamin C small animal supplement is essential in promoting a healthy life for your guinea pigs, and other animals may benefit from it as well to promote overall health. Apply a few drops of the guinea pig supplement to your pet's water bottle, or mix a few drops into their kibble. This vitamin C small animal supplement is formulated with the guidance of leading veterinarians and nutritionists and contains no artificial flavors, colors, or preservatives.