If the battery shows less voltage or won't take a charge, it's time to get out the hydrometer. This device checks the proportions of sulfuric acid and water in the electrolyte, which is a precise indication of the level of charge.
Common causes of cat hair loss, or alopecia, can range from allergic reactions to hormone imbalances to an infestation of some pest or another. Although the different causes can be difficult to pinpoint, most are fairly easy to address and remedy.
If you notice hair loss on your cat's ears, don't hesitate to take him to your vet. The quicker the cause is diagnosed, the more easily it is treated, and you can prevent the problem from getting completely out of hand. In many cases, the hair on your cat's ears will eventually grow back.