Physiological condition, rather than chronological age, determines whether a dog is mature. Aging begins when the body's systems start to slow down, when cells deteriorate faster than the body can repair them. Though large breeds tend to age faster than smaller breeds, the mature years generally begin at around 7 years 5 years for large breeds. If you feed your dog a diet designed to address the nutritional needs of his age, you can best maintain his overall health and well-being. As your dog ages, it is important to detect and address with his veterinarian the telltale signs of aging or disease: a dull, dry coat and flaky skin, joint stiffness, energy loss, weight gain, increased water intake, digestive problems, and frequent constipation.

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Because dogs evolve as they mature, they require different approaches to healthcare as they progress from puppy to senior. In fact, there are at least 10 health-related factors based on age, size, lifestyle, health status, and breed that your veterinary team regularly assesses to keep your dog healthy, happy, and safe. A mature adult dog has different needs than a puppy, young adult, or senior dog.