As our dogs age they tend to have more lumps and bumps on them. Even if they are not seniors, dogs can get lumps that may need to be looked at. It is very important to look at your dogs very closely and sometimes looking just may not be good enough. If you have a very full, dense coated breed it can be difficult to see what's going on under that coat. So touch is very important. When it is time for a shave for my guys I am happy to get the big thick coat off and have a good look see.
But even when they have a full winter coat I often optimize the use of my forced air dryer to it's fullest. Not only is it a great device to dry my dogs but it blows their coat completely open allowing me to see inside. I have found several lesions and marks that needed looking into by using my dryer. When it is nail time I make it a habit to feel toes, spread them out, get my finger in there to see if there might be any thorns or such. I have found several things in there that needed removing and that the dogs weren't working to get out. Sometimes they are fussing to pick something out of their coat or foot that let's me know but often they give you no signals that there may be a problem.
How about their teeth, how's the old pearly whites looking? And breath, how's your dog's breath? That is a big heads up to mouth problems or worse if they have very bad breath. Even old dogs should not have bad breath if their teeth are good and they are healthy. It's won't smell like roses but it shouldn't knock you over either.
Do the visual check on a weekly basis. How's your dog walking? Any limp? Favoring? Are they panting more than normal? Do they seem to be sleeping well? Very small changes in the norm can be a sign of a problem and there is no one who should know your dog better than you do, that is if you are paying attention. There are also seeing and hearing tests that should be done regularly as your dog ages. It is easy to see if they hear or see well, but you must test it. Dogs are very good at manouvering around a familiar surrounding so you must test them to be sure. Calling out when they aren't looking or are in another room, dropping food on the floor and throwing toys for them is an easy way to tell how well they can see or hear.
Along with all the regular stuff that we do for our dogs, general maintenance is very important. Keeping on top of things before they get out of hand is always a good idea, even with our dogs.