Small Breed Dog Food for Senior Dogs: Purina Pro Plan AdvantEDGE Senior Support Plus delivers Pro Plan’s most advanced nutrition, providing 3-in-1 Senior Support for small dog breeds. Cognitive Support: This senior dog food small breed formula features bright mind technology shown to promote mental sharpness in dogs age 7 plus. Immune Support: Senior adult dry dog food made with real chicken for dogs with a specialized blend that supports immune response in senior dogs. Mobility Support: Small breed high protein dry dog food delivers glucosamine and EPA to support joint health and mobility. Supports Digestive Health: Dry dog food features a highly digestible formula with probiotics for dogs to support digestive health.