Disclosed herein are methods and compositions which are useful for a companion animal, wherein the methods and compositions utilize astaxanthin. The compositions comprise astaxanthin, wherein the composition is adapted for use by a companion animal. The methods are selected from the group consisting of attenuating inflammation, enhancing immunity, enhancing longevity, and combinations thereof, comprising administering to a companion animal a composition comprising an effective amount of astaxanthin. The companion animal is, in the preferred embodiment a domestic dog or cat.
