This is Mistyfield's Sir Reese Of My Heart CGC He's 8. He's my best bud, the best dog I have ever had. My retired Service Dog. Highly trained, was a perfect puppy, dream to train, just perfect. Awesome with everything and everyone. Never bitten or even growled at a human. Suddenly, I am noticing that when he once had a perfect recall off leash at a distance (We have 4 acres and when I let him out I just open the door, he goes off a few feet, does his thing, comes right back while I wait) I now have to repeat myself a couple of times loudly before he comes. Today I called him to give him his heartworm med and flea and tick spot treatment, and also his yearly 8-way shot and when I called him from the kitchen (he was in the dining room right off the kitchen) he got up from laying down and walked into the living room tail wagging looking for me (in the opposite direction). I called him again and he turned around and came to me like nothing was amiss. I have never had a dog this long before. I don't know the signs of dog aging. At 8 could his hearing be starting to go? He's snoozing under my desk right now, always the loyal companion.