The toy rests where it stopped, beckoning to her. Mesmerized, Betsy springs from her hiding place to resume the chase, which continues until she's had enough to eat. Then, Betsy turns her back on the "kill" and pads off, gracefully lifting a paw to her mouth to begin grooming.

Playing with enticing food-filled toys helps satisfy a domesticated cat's natural hunting instincts, says her owner, Daniel Carey, DVM, director of technical communications in research and development at IAMS Co., Dayton, Ohio. "The cat has to hunt for its food. It fulfills a need and gets them up and around and moving," he says.

Feral cats, on the other hand, spend much of their day prowling for food - usually mice and birds. Once they catch the prey, the cats tend to enjoy playing with it, letting it go briefly, before pouncing again and finally killing the animal, all part of the thrill of the hunt.

"If [our pets] were wild, food and shelter would be the focus of cats' lives. When we feed them out of a bowl, they lose some of that," Dr. Carey says.

"Evolution never left a bowl of food around. The excitement and joy and thrill of the kill are removed when we feed cats from a bowl," agrees Rolan Tripp, DVM, an affiliate professor of Applied Animal Behavior at Colorado State University's Veterinary School. Although most indoor cats lead healthier, longer lives than cats forced to forage for their own meals, many cats also get less exercise than their outdoor brethren, which can lead to weight gain and other health problems as they age. For example, significant weight gain is related to diabetes, says Rebecca Remillard, DVM, Ph.D., a board-certified veterinary nutritionist who practices at Angell Memorial Animal Hospital, Boston.

Your indoor, bowl-fed cat doesn't have to be a sedentary, lazy mass of fur, say veterinary nutritionists. To avoid this, you need to understand your cat's nutritional needs, avoid harmful foods, find the appropriate food, and figure out the ideal manner to serve it.

Can't Live Without It
Cats are obligate carnivores: they must eat meat to obtain all of the nutrients they need to stay healthy, Dr. Remillard says.

Cats get taurine, vitamin A and an essential fatty acid called arachidonic acid, a vital component of cell membranes, from animal sources, Dr. Carey says. Taurine is an amino acid used to maintain normal bile function and healthy eyes and heart. It is continually lost from the body as the bile acids flow to the gall bladder, then into the small intestines to digest fat and are eventually expelled from the body in feces.

Taurine needs to be constantly replaced, Dr. Remillard says. A kitten raised without it will go blind or develop cardiomyopathy, a fatal heart disease, Dr. Tripp says.

Choices, Choices, Choices
All quality cat foods should comprise 43 nutrients, Dr. Remillard says. Within these, cats need protein for healthy body tissues; carbohydrates for energy; fats for absorbing and storing vitamins to maintain a healthy coat; vitamins for metabolism; and minerals for healthy skin, hair and development.

Knowing this, you're off to purchase the appropriate food for your cat. However, with the myriad choices available, how do you decide which formula is best? Is your cat a kitten, adult or senior? Should you get premium, grocery store, generic or prescription food? Does your cat require a formulation for hairball care? If you have a purebred kitten, ask your breeder what it's been eating.

If your cat has a special condition, ask your veterinarian about prescription food. Among others, there are formulated foods for urinary tract or kidney problems, excessive hairballs, tartar buildup and food allergies. Also speak to your veterinarian if your cat is experiencing vomiting or diarrhea.

In addition to these specific needs, consider the following questions before purchasing cat food:

1. Should you buy dry, moist or canned food? Because soft/moist foods are loaded with preservatives, you should save them for the occasional treat, Dr. Tripp says. Canned foods require fewer preservatives, but cats tend to like the taste more than dry, and they're likely to eat too much and put on weight. Plus, any uneaten food left in the bowl has the potential to spoil. On the other hand, nutritious dry food can be left out all day, allowing the cat to graze as it pleases.

"They will go to the canned food every time. But it's not as dense, so the cat has to eat more. Just leave dry food out all the time. The cat will now nibble," Dr. Carey says. "I don't see any need for canned food. As a rule of thumb, use dry food, unless you're trying to put weight on the cat," Dr. Tripp adds. Dr. Remillard advises saving the canned food for when the cat is sick or needs to be given a pill.

2. How much can you afford to spend? The less expensive food may not be the most economical, Dr. Carey says. Premium cat foods, which should use higher-quality meat, are more nutrient-dense, so your cat will eat less to gain the calories it needs, he says. The difference in actual cost may only be a penny or two more a day for a premium food.

"Feed them premium food. There's no issue there. Give them good raw materials,'' says Dr. Tripp, who feeds his three cats a premium brand.

3. How are ingredients listed on the label? Ingredients should be listed by weight, Dr. Remillard says. If chicken or chicken by-product meal is one of the first items listed, the diet is high in protein. If corn is first, it is particularly high in carbohydrates. The food should be relatively low in carbohydrates, Dr. Carey says. Certain types of carbohydrates (e.g., rice) have high glycemic indices, which cause sugar to be absorbed into the cat's system too quickly, he says. Corn is needed to slow down sugar absorption.

When reading food labels, look for a minimum of 28 percent protein for adult cats; 31 to 32 percent is normal. The fat content should be at least 21 percent. There should be six percent minerals, two percent vitamins, about three percent fiber and approximately 36 percent carbohydrates.

Consult with your veterinarian to determine the best food for your cat on the basis of its age, lifestyle and activity level. "Feed to correct body shape, not the bag," Dr. Tripp says.

Once you've decided on a particular brand and formula, check the label to be sure the Association of American Feed Control Officials (AAFCO) has tested it, Dr. Remillard says. AAFCO develops and directs the regulations and standards for the manufacture, distribution and sale of animal foods, resulting in a safe product for the consumer.

"If the AAFCO statement meets the cat's requirements, then it's a perfectly good, reasonable food to try," she says. "If it's in your price range and you can get it near where you live, give it a try."

The Taste Test
If you thought educating yourself about cat foods was tough, now you have to get your cat to eat what you've picked out. If you're introducing a new food to an adult cat, don't switch it all at once. Mix in a small amount of the new food with the old for 10 days, gradually increasing the amount of new food.

Kittens may take more easily to a variety of foods if you start when they're first weaned, Dr. Tripp says. "Kittenhood will influence their view of food. Try a few different forms in kittenhood and broaden their spectrums,'' he says. The variety it receives will make it less likely to be a finicky adult eater.

The feeding routine is also important. Will you be meal-feeding two or three times a day or leaving dry food out for free-choice feeding? What works for one cat might not work for another. "Cats are more different than they're alike,'' Dr. Remillard says.

Some cats crave a quiet spot away from the noise of children and other animals, others are perfectly content dining on the floor next to you at the kitchen table. If your cat doesn't seem comfortable, or it's not eating properly, try a different arrangement; putting the food in a place only it can reach is oftentimes a solution.

"A quiet setting is probably important, especially if you have dogs and cats and you want them to eat in peace,'' Dr. Carey says. You might also want to feed cats with different dietary needs in separate rooms to keep them out of each other's food.

Some cats are fussy about the temperature of their food. Most like it between room and body temperature, Dr. Remillard says. If they like canned food warm, heat it in the microwave for a few seconds, but be sure to stir it afterward to avoid hot spots.

Even the material bowls are made of affects your cat's eating habits. Plastic bowls have a tendency to trap odors, according to The Purina Encyclopedia of Cat Care, by Amy D. Shojai (1998, Ballantine Books, $24.50). Ceramic bowls made in the United States are probably the best bowls to use, also according to the book. The glaze in foreign-made bowls may contain lead. You might consider heavy glass bowls, which do not move across the floor as the cat eats. Stainless steel bowls are easily cleaned, but the cat might dislike how the food tastes in them. You'll just have to experiment to determine which bowl works best for your cat.

Clean, fresh water is vital to your cat's health. Many cats refuse to drink stale water, which can lead to dehydration. "It doesn't take long," Dr. Remillard says. An average 10-pound cat needs to drink about one and a quarter cups of water a day, she says. And most adult cats should not be given milk because they lack the enzyme to digest lactose, she says.

A cat's ideal weight depends in part on its breed and body conformation, Dr. Carey says. A Cornish Rex, for example, is naturally thin and a domestic shorthair is somewhat tubular in shape. A Maine Coon may be perfectly healthy at 20 pounds.

The average cat weighs about 8 pounds, he says. In general, you should be able to feel the ribs, but not see them. And on the other extreme end of the scale, the cat's flank folds should not shift from side to side as the cat walks.

"You should not see the tidal effect as the cat moves away from you,'' Carey says. If only feeding your cat was as simple as putting kibble into the crevices of a plastic toy. The challenges cat owners face when making responsible decisions to ensure their cat's health and well-being are more complex than ever. However, with an understanding of what constitutes a well-balanced diet and the specific nutritional needs of your cat, dinnertime could very well be playtime.