A 10- to 12-year-old dog, depending on his size and individual variation, is roughly the equivalent of a 60- to 90-year-old person. By now, youve likely realized that your dog is slowing down. He may still enjoy a long walk, but he is not quite as zippy as he used to be. You might even notice that he sleeps more or takes a bit longer to rouse or respond to commands. Regular veterinary visits can help determine whether those changes are normal aging or signs of illness. Though your dog is ...