The invention relates to particles suitable for oral administration of a composition to an animal. The particles comprise a substantially indigestible polymer matrix. In one embodiment, the matrix contains the composition and a lipid that is dissoluble in the animal. In another embodiment, the matrix is mixed with the composition and contained in a dissoluble coating. The lipid and coating can be ones which are preferentially dissoluble in one compartment of an animal than in another. For example, the particles can be made to preferentially release the composition in the intestines, rather than the stomach, of a mammal, a fish, or a crustacean. Examples of compounds which can be administered in such compositions include vitamins, fatty acids, oils, carotenoids, nutraceuticals, pharmaceuticals, live or dormant probiotic bacteria, hormones, nucleic acids, and proteins. The particles described herein have the further advantage that they can protect sensitive compounds from oxidation, taste or odor change, and other types of degradation.
