Grooming
Paying attention to your Chihuahua's coat, skin and nails is just as important now as it was when your Chi was in her prime. Brushing or combing your Chihuahua daily makes you very familiar with your dog's normal body contours. By knowing what is “normal,” you will quickly spot any suspicious lumps, bumps or tender areas on your Chi's body.
Diseases of all kinds have the best potential outcome if they are caught in their earliest stages.
Senior dogs, particularly those that are overweight, frequently develop fatty tumors or lipomas. These are harmless, spongy tumors that can be found just under the skin. Even if you think the lump you've found is a lipoma, have your veterinarian check to confirm that the lump is not a more dangerous tumor, such as a mast cell tumor (MCT).
MCTs often appear on older dogs and vary in their appearance. Some MCTs are relatively benign in that they are slow to grow and don't seem intent on spreading. More aggressive forms of MCT metastasize or spread to the dog's lymph nodes, bone marrow, liver, and spleen.
Brushing
Another change you may notice as you brush your dog is the beginnings of a sore on his tail or paws. Often, older dogs become bored and will lick themselves as a response. The licking can become obsessive with the Chi actually licking away layers of skin to create sores. More involvement and activities with your Chi will help him in the long run. In the short term, seek veterinary advice on healing the sores and preventing more damage.
Daily brushing, of course, has many other benefits. Whether you have a shorthaired or longhaired Chihuahua, grooming your elderly Chi not only provides you with opportunities to spot disease in its early stages and gives her added quality time with you (reducing the boredom factor), it also increases blood flow to the skin. Increased blood circulation to the surface provides aging skin with much-needed nutrients.
Brushing also works to counter dry, flaky skin that is so often a problem with aging dogs. Brushing all the way to the skin (more difficult but exceedingly important with longhaired Chihuahuas) stimulates the secretion of oils, a natural lubricant that keeps the dog's skin from becoming dry and flaky. These oils, when spread evenly throughout the dog's coat (by brushing), also work to make dull, dry hair more lustrous and less brittle.
Toenails
You would think that age would slow the growth of a dog's toenails. In reality, many elderly dogs have issues with nails that are far too long. The reason for this is most often that the aging Chihuahua has become less active. Without her frequent, long walks around the neighborhood or in the city, her toenails aren't being naturally filed down every day by the concrete surfaces of sidewalks and streets.
Don't forget to look between your Chi's toes. If she is longhaired and tends to grow hair between the pads of her feet, this can cause her to slip and slide on slick floors. Keep these areas neat and trimmed short so she can get as much traction as possible.
If a Chihuahua's toenails are too long, you will hear them clicking when she walks on a hard floor. This affects the Chi's mobility. Long toenails cause the foot to spread and shifts the dog's balance from a more forward position on the toes to the heel of the paw. Think of it as wearing stilettos, only backwards. Your Chihuahua is more likely to slip, become unbalanced, and even fall. And, if your Chi has any soreness at all in her joints, long toenails will seriously affect her ability to move and can cause lameness. Cut those toenails!

