Help your large breed senior dog fight signs of aging with IAMS PROACTIVE HEALTH Large Breed Senior Plus Dry Dog Food. Our hearty dog food is made with real chicken as the first ingredient, plus naturally sourced chondroitin sulfate and glucosamine, our senior dog food for large breed dogs 9 years and older is designed to promote lean muscles and nourish healthy joints. IAMS PROACTIVE HEALTH Food for Dogs also is enriched with antioxidants for a strong immune system. Your senior dog will love the savory poultry flavors, and you will like that e