Dogs are considered senior at age 6 to 8, and cats at age 7.  Both cats and dogs age approximately 7 equivalent human years for each year of their life.  So, your 6 year old lab is pushing 50 and your 9 year old cat is 63. 

Why is this significant?

As with humans, aging can have significant impact on how well our joints, skin and organs function.  It is much easier and less costly to treat any changes early.  Your veterinarian can work with you to detect and anticipate these changes to maintain the quality of your pet's life.