Complete Care for Your Aging Cat - Amy Shojai [18]
How Age Affects the Body
Most cats begin to slow down a bit by the time they reach seven to ten years. These changes are very gradual and subtle, though, and often we don’t notice any significant changes. For instance, the cat may begin seeking out warm spots that help creaky joints feel better, or sleeping an extra hour or so each day. Even the veterinarian may not detect aging changes without special tests, until they become obvious, at which point the damage may be irreversible.
Understanding how age affects the different body systems will help you become alert to subtle changes that may point to serious problems. Catching medical problems early offers the best chance of successfully treating them, and keeping your cat happy and healthy.
The Senses
Cats rely on their senses to a much greater degree than do people. They use touch, taste, scent, sight, and hearing to learn about the world around them, and connect with their people. They rely particularly on hearing and sight, and scent and taste to a lesser degree.
Normal aging in the sensory organs affects all cats. In addition, exposure to environment insults often causes damage to the sensory organs, which means they dim over time. Taste bud numbers decline, and the sense of smell is often the first to show the effects of age, often with loss of appetite. As far as we can tell, though, the cat’s enjoyment of the touch sensation—petting, snuggling, and contact with beloved owners—does not change with age. Cats that develop problems regulating body temperature may, in fact, become more likely to want to snuggle in a warm human lap as they get older.
All cats suffer from a certain amount of visual and hearing impairment, says Benjamin Hart, DVM, a veterinary behaviorist at the University of California-Davis. “Certainly that’s an impact on behavior.” Yet sensory loss usually bothers owners much more than it bothers the pet. Cats are able to compensate for vision or hearing loss to such an extent that we often don’t recognize there’s any problem until very late in the game.
Aging Eyes
A cat’s eyes are designed for a night predator. Vision is arguably the most important feline sense of all. “Visual acuity in the cat is fairly close to that of the human, probably a little less,” says Lawrence Myers, DVM, a professor of anatomy at Auburn University. Cats pay exquisite attention to the world around them, and are particularly adept at discerning motion out the corner of their eyes.
Cats with prominent eyes such as Persians are more prone to damage and chronic inflammation from scratching or bumping their eyes, but this can happen at any age. Cats do not have a particular age-related eye problem, other than nuclear sclerosis, says Harriet Davidson, DVM, an ophthalmologist at Kansas State University (now at Michigan Veterinary Specialists). That is a normal change of age that causes the lens in the eye to turn hazy. “It’s the reason humans have to get glasses when they turn about 40,” says Dr. Davidson. “Your lens is not as flexible so you can’t see up close anymore because it can’t accommodate. Elderly animals will have a pupil that looks somewhat bluish or milky in appearance.”
Cats can see through the haze and still function well. Nuclear sclerosis is different from cataracts, which ultimately result in complete opacity of the lens and blindness. “Cataracts occur at all ages, but there’s more likelihood as an animal ages, just as a person, that