Middle age for dogs begins when they reach the halfway point of their lives. As a general rule, that happens around the sixth or seventh year of life. But some dogs age faster than that. Breed and size typically determine average life span for a healthy dog.
Small dogs tend to live longer than larger breeds. The Chihuahua has a life expectancy of 15 years or more, so middle age doesn't hit until year eight or so. Toy poodles and miniature dachshunds live an average of 12 to 15 years, so middle age comes around when they're about 6 or 7 years of age.
Medium and Large Dogs
The larger the dog, the shorter the life span -- so it makes sense that middle age comes sooner for large breeds. Healthy bulldogs live about 10 to 12 years, according to WebMD. Based on that, they're considered middle-aged by the time they reach 5 or 6 years. The Irish wolfhound has one of the shortest life expectancy of any breed: between six and eight years -- a specimen could be middle-aged at the age of 3.
Health Concerns During Middle Age
As dogs reach middle age, a variety of health problems start to appear. Because dogs slow down -- they don't run or exercise as much or as hard -- during middle age, they tend to gain weight. This can bring about other health issues, such as additional burden on the liver or heart disease. As dogs age, they become more likely to develop kidney disease, as well as muscle and bone problems. Hypo- and hyperthyroidism and other internal process failures begin to manifest past middle age, too.
Keeping Your Pup Healthy and Happy
Making adjustments as your dog reaches middle age is important to help him live a longer life. For example, if you notice your dog limping or panting heavily after a walk, try adjusting the intensity of the workout. Also, ask your vet how frequently you should be going in for a checkup. As dogs get older, they need blood tests more frequently to make sure you catch problems early on. Ask your vet about dietary changes.
Tammy Dray has been writing since 1996. She specializes in health, wellness and travel topics and has credits in various publications including Woman's Day, Marie Claire, Adirondack Life and Self. She is also a seasoned independent traveler and a certified personal trainer and nutrition consultant. Dray is pursuing a criminal justice degree at Penn Foster College.