Babies grow out of diapers, but pets never outgrow the need for scooping.

Chaser sometimes shuffled along like an old lady dog, but mention the "C word" — cookie — and she magically transformed into a spry puppy. Of course, you had to holler "cookie" or she wouldn't hear. Still, for a 14-year-old Brittany, my dog seemed to be doing well.

There was no compelling reason to visit the veterinarian soon, but I had been preaching the gospel of twice-annual vet visits in my columns, on my radio shows and in TV appearances. So I wasn't worried about anything being wrong with Chaser. After all, if anyone should pick up on subtle signs of illness in pets, it's me. Right? Well, maybe not.

A few days before the scheduled vet visit, I noticed a growth under Chaser's tail. Now I was worried. My vet, Sheldon Rubin, here in Chicago, later confirmed my concerns: The growth was mast cell cancer.

Of all the words in the dictionary, "cancer" may be the one we least want to hear. But Rubin told me, "We caught this early, and that could save your dog's life."

Within a few days, Chaser had surgery. There was no advantage in continued treatment such as chemotherapy or radiation. Later, a veterinary oncologist said, "If Chaser can make it a year, you're probably in the clear."

She made it. Sure, at times, Chaser could use a walker made for dogs, and a hearing aid would be helpful — but all in all she's doing fine. Say the "C word" and there's still a bounce in her step.

My vet says, "If you had waited just six more months, which might on the surface sound reasonable, the cancer would have spread or the tumor would have grown to be inoperable."

The American Veterinary Medical Association and Fort Dodge Animal Health (a maker of pharmaceuticals for pets) are partners in a campaign to encourage twice-annual wellness exams for all pets. (Wellness exams deal with important health screenings, immunizations, parasite checks, dental health and laboratory evaluations.) Dogs and cats age five to eight times as quickly as people do, so even seeing a vet annually is like you seeing a doctor or dentist once every five to eight years. In fact, a pet's health can change so quickly that even biannual exams aren't a perfect solution, but paying careful attention to subtle signs of sickness helps (see sidebar on next page).

Going to the vet twice a year would mean a pretty big change in behavior for most pet owners (see box below). It looks like many dogs make it to the vet at least twice a year, but I think the figures are inflated, because most repeat visits were follow-ups to illness, surgery or a procedure — not wellness visits.

Of course, some people may suspect that vets are eager for extra visits to make extra bucks. But that additional visit may save you money. "Sure, if the checkup turns out to be perfect — which is what we all hope for — you've invested some money for an exam," says Rene Carlson, a vet in Chetek, Wis., and vice president of the AVMA. "But what if we do find something? Just as in people, an early diagnosis may mean a better prognosis, less suffering for the pet and less money spent by the client, because the treatment may not be as prolonged. It's all about prevention."

But not everyone is on board with the twice-a-year physicals for all pets. Leonard Marcus, of Newton, Mass., is a veterinarian as well as a medical doctor who deals with infectious diseases. He says individual discretion is the better part of good health. "The pet owner and veterinarian should discuss a game plan that's right for their individual circumstances, greatly depending on the pet's age and general health," Marcus says. His idea is that an elderly pet or one in poor health might visit a vet even three times a year, whereas a younger or middle-aged pet in excellent health might be just fine with annual visits.

Carlson disagrees: "Even in younger pets, we can find the unexpected." One recent example was a 2-year-old Labrador retriever who the owners thought was perfectly healthy. A six-month routine physical discovered roundworms, which are easily treatable. However, roundworms are zoonotic, meaning they can infect people, potentially causing blindness. Diagnosing the condition sooner rather than later helped prevent discomfort for the dog and averted a health risk for the people around that dog.

Even though there are 20 percent more pet cats than pet dogs in America, cats visit the vet only about half as often. "It might be we're just better at reading what dogs are trying to tell us," says James Richards, director of the Cornell Feline Health Center at Cornell University College of Veterinary Medicine in Ithaca, N.Y. "Or maybe people believe that cats, because they are so independent, can manage on their own without medical care. Of course, if something is wrong, they require veterinary care just as dogs do," adds Richards, spokesman for a campaign to educate cat owners on how to watch for subtle signs of sickness.

In the wild, a cat showing signs of illness is at risk from predators, and that's even truer for birds and reptiles. "These are animals who may only be a few generations from the wild," says Byron de la Navarre of Chicago, past president of the Association of Reptilian and Amphibian Veterinarians. "If a bird or a lizard acts sick out in the real world, that animal becomes dinner. It's a matter of survival to pretend that all is well no matter how poorly the animal feels."

With seven assorted birds, you'd figure that for simple economics, Grace Cermak of Chicago would only visit a veterinarian when one of her flock is ill. "It's the opposite," says Cermak, a risk analyst for a hardware store chain. "Jumping ahead of illness [with twice-yearly vet visits] is really important with birds. In the wild, when a parrot acts sick, fellow flock members will reject it. Once that happens, the bird's fate is sealed."

An avian vet recently found a mouth infection in Popeye, a chatty 14-year-old blue-crowned conure who was in for his twice-annual exam. "We had no idea there was anything wrong," Cermak says. "Now, it's a matter of simply treating with an antibiotic."

Contributing Editor Steve Dale is heard weekly on WGN Radio and on his syndicated radio shows, Steve Dale's Pet World and The Pet Minute with Steve Dale. He also writes a syndicated column, "My Pet World."