Some experts have credited the invention and improvement of cat-box fillers as the driving force behind the feline rise in popularity, and certainly such a case can be made.

Before absorbent fillers became widely used and accepted, cats were mostly outdoor pets that our kind didn't appreciate for their companionship as much as we should have. After modern litter took off, however, cats became an integral part of the lives of an ever-increasing number of people. The rest, as they say, is history: Cats rule!

Here are your choices when it comes to thinking inside the box.

-- Clay. More than a half-century old and still a significant part of the market, fillers made of clay started the cat on the road to popularity. Clay is one of the least-expensive options in terms of price per pound, but you need to use more of it because the material needs to be completely replaced weekly to combat bacteria and odors. To remain competitive, the makers of clay litters have done a great deal to make their products more attractive, with the addition of deodorizers, dust-reducers and more.

-- Clumping. Also called "scoopable" litter, clumping has a high level of popularity among both pets and their owners. These materials dissolve around the moisture in urine or feces, reforming as a lump encasing the mess, which can then be easily scooped, raked or sifted out. Because the entire mess is scooped out each time -- assuming the clump doesn't break -- odor problems are minimized.

Although clumping litters are more expensive per pound, they require you to use less because all you need do is replace the litter you've removed with the waste. Although clumping litter does need to be replaced eventually in its entirety, that chore doesn't need to be done as often as with clay litters.

Drawbacks to clumping litter include tracking problems, because the material that sticks to moisture on cat mess clings just as easily to moisture on cat paws. A mat around the box will help knock the granules off your pet's paws before they end up all over the house.

-- Alternative litters. There's no end to the creative minds that have been active in the creation of new cat-box fillers. You'll find products made from wood fiber, corn cobs or kernels, and pelleted newsprint and other materials (some of them recycled from other uses).

Because the range of products in this category is so varied, it's hard to generalize about them. Some of these products, such as the corn-based World's Best Cat Litter, collect marvelous reviews and a dedicated following, while others come and go quickly.

Which kind of cat-box filler should you choose? Each variety has its benefits and its followers. Clay litters maintain a hefty share of the market to this day, which says this industry-starter is obviously still the right choice for many cats. Clumping litter's ease of use has made it a popular choice, and many behaviorists say it's best in terms of what cats prefer. And I know of cats whose homes (and probably lives) have been saved by the use of an alternative product when nothing else could get them to use their boxes.

Today's choices of cat-box fillers are mind-boggling, and when choosing one, it's essential that you keep in mind who the real customer is here: your cat. It doesn't matter how much you like a filler for its no-tracking, low-dust or odor-control properties. If your cat doesn't like it, you'll be finding waste in places you neither anticipated nor wanted.

Find the brand your cat likes, and then keep the box scrupulously clean. It's the only way to go.

PETS ON THE WEB

The Maine Coon is one breed of purebred cat whose popularity has grown in recent years, which means some of these large, sweet-natured cats are turning up in shelters. Rescuing and finding new homes for these down-on-their-luck kitties is one of the goals of the Maine Coon Alliance Web site (http://mainecoonalliance.vjungle.com), which also offers information on the breed and few imaginative features as well.

THE SCOOP

Now that gardening season is in full swing, a lot of people are thinking about compost piles and wondering: Is it OK to recycle pet waste in this way? It depends on your pet. If you have a pet that eats plant matter -- rabbits, guinea pigs, rats, hamsters and mice fall into this category -- then sure, compost their waste. It'll be great for your garden.

The waste of carnivores such as dog and cats should never be composted, however, because it could carry disease. With these pets, put the waste into bags, wrap up tightly and put into your regular trash. I always use old pet-food bags for waste disposal -- they're sturdy enough to stand up to reuse before being discarded.

QUESTIONS FROM THE PACK

Q: A few months ago I ran over my beloved cat in my driveway, and I've been having a hard time ever since, as you can imagine. Eventually I intend to get another pet, but the last two cats I've had both "adopted" me and were indoor-outdoor cats. I've never had a cat box except when they were spayed and needed to stay indoors for a while, and I have a cat door.

I've been worried about whether to have the same system with my next cat, and I was interested to read your column about moving cats. You seemed to indicate that it's a good thing to have a strictly indoor cat. Could you give me a little feedback on this? -- D.C., via e-mail

A: Yes, I do believe in keeping cats indoors, but I'm also enough of a realist to know that some people will always allow their cats to roam. I also trust that pet lovers always try to do what's best for their animals, and I believe that differences of opinion are what makes the world the interesting place that it is.

That said, there are compelling reasons for keeping cats indoors, and safety is tops among them. You are not the first person to have run over your cat -- I know of at least one other person in my extended circle of acquaintances, and at least a half-dozen readers in the last few years. And your own car certainly isn't the only risk out there.

Outdoor cats are run over by cars, attacked by dogs and coyotes, trapped intentionally by cat-hating neighbors, and trapped unintentionally by cat-neutral garages, outbuildings and basements. They get into poisons, contract diseases from other cats, and end up with painful and expensive injuries following cat fights. Seeking warmth, cats become injured when they snuggle up in still-warm car engines.

People who resent cat mess in their gardens or paw prints across their cars argue that cats are a nuisance. Free-roaming felines can also be a threat to birds and other prey animals, some of whom may be endangered. (Although to be fair, the biggest threat to these birds and small animals isn't cats, but the claiming of habitat for development or livestock grazing, here and in developing countries.) You might also be breaking the law by letting your cat out, since many communities have established laws against free-roaming cats.

Cats live longer, healthier lives inside, but can they also find happiness? Yes! Make sure your pet has a good cat tree, lots of toys and plenty of your attention. A screened-in porch or other safe access to fresh air is also tops on the list, but many cats do fine without them.

Converting a cat to the indoor life can be a trial for you both, but it can be done with patience and persistence. It's by far easier, though, to start a cat or kitten out indoors from the first day in a new home.

Q: Can you please explain how to put on a choke collar properly? I'm tired of seeing people walking their dogs with it on wrong. -- C.N., via e-mail

A: With the dog sitting on your left, make a downward facing "P" out of the collar, with the base of the letter on your side. Then slip the collar over the dog's head. The moving end of the collar should go over the dog's neck, not under it. If it's put on incorrectly, the collar will not release easily when the leash is slackened.

The choke collar is one of the most difficult pieces of training equipment to use properly, which is why I have in recent years discouraged its use. Newer products such as head halters are easier to use and provide control with less strain on the dog.

Gina Spadafori is the award-winning author of "Dogs for Dummies," "Cats for Dummies" and "Birds for Dummies." She is also affiliated with the Veterinary Information Network Inc., an international online service for veterinary professionals. Write to her in care of this newspaper, or send e-mail to writetogina(at)spadafori.com.

4520 Main St., Kansas City, Mo. 64111; (816) 932-6600

Spring can be sneaky when it comes to putting your pet at risk. That's because heat can cause problems for pets, even on days that we would consider merely warm.

Dogs are most vulnerable. We get comfortable with taking our dogs on errands in the cooler months, leaving them in the car while we run into the grocery, dry cleaner or pharmacy. While no intelligent pet owner would leave a dog in the car on a day in the 90s or above, it's easy not to realize the risk when the temperature is in the 70s and 80s.

The trouble is, a temperature that's pleasant outside of the car could end up being very hot inside, even with the windows cracked. Cars are like greenhouses, collecting heat through the glass of their windows and allowing it to build up inside. Even on days in the 70s or 80s, a car in the sunshine can become uncomfortably warm -- and even deadly if left long enough. Dogs are not efficient at cooling themselves and can die quickly in a hot car.

The best solution? Leave your dog at home. It's not all that great an idea to leave your dog in the car even when warm weather isn't a problem. Pet thieves aren't all that common, but they are out there (as are car thieves, who won't care a jot about your pet if your vehicle is stolen).

Hot cars aren't the only heat danger -- exercise is another. Many of us get a wild hair about exercising in the spring, sometimes starting running programs that neither people nor dogs are fit enough to start. Whether you're an established exerciser or a beginner, remember that in warm weather it's better to take your dog out in the cool of morning, and then build up your time and distance slowly.

If your pet is old or overweight, don't start until checking with your veterinarian. Exercise is great for you and your dog, but only if done properly and with an eye toward safety.

Here are some additional springtime safety tips for all pets.

-- Keep caged pets from overheating. Make sure cages for birds, reptiles and small mammals are placed in an area that's well-lighted but out of the direct sun. Pets who are kept in cages have no ability to leave an area if it becomes too hot, so it's up to us to make sure their environment is comfortable.

-- Make sure pets always have clean, fresh water. Dishes and water bottles should be emptied, rinsed and refilled a couple of times a day. A thorough cleaning with warm soapy water (rinse well) should be done at least weekly. Check water bottles frequently by pressing your finger against the tip to make sure there is no blockage. Some clever parrots love to make a game out of pushing food into the steel neck of water bottles, so be on alert if yours is one of these tricksters.

-- Beware of chemical hazards. Spring is a great time for shade-tree mechanics to work on their cars, but be sure to carefully clean up any spills. Most deadly among the car-related fluids is coolant. A cat can die after walking through an antifreeze spill and then cleaning the liquid off his paws. In recent years, products have come on the market that are not so lethal; check them out at your auto-supply store.

Household chemicals claim unintended victims every year as well. Keep pets out of areas where snail bait, insecticides or poisons intended for rodents are in use. As for herbicides and fertilizers, follow directions carefully and do not allow pets into a treated area until the chemicals have dried.

Spring is a wonderful time of year, and you and your pet will enjoy it more if you take a few preventive measures to ensure that the season will be a safe one.

PETS ON THE WEB

Dogs who hunt by locating prey with their eyes instead of their nose are called sight hounds, and the category includes breeds who are the canine equivalent of the cheetah -- long of leg and body, and built to run fast. The best-known of these breeds is arguably the greyhound, but there are others, such as the Irish wolfhound, Afghan hound, borzoi, whippet and saluki. The 20-20 Hound Site Web page (http://log.on.ca/canine/2020houndsight/index.html) celebrates these elegant dogs, and provides information on the breeds and on the sports in which they compete.

Don't look here for information on upcoming competitions, as the calendar page has not been updated for 2001. And in the breeds area, you'll find some holes in the information offered. But you'll still find plenty of value, including breed profiles, articles on coursing, and plenty of gorgeous pictures of sight hounds at full speed.

THE SCOOP

Iguanas should be fed plant matter only, a mixture of vegetation that's high in calcium but low in phosphorus and fat. Choices include mustard, collard and turnip greens, as well as yams, carrots, alfalfa sprouts, alfalfa hay (or pellets) and squash. Dog and cat food is a no-no.

Chop fresh or frozen vegetables into a size that can be easily handled by the pet. Mix it and then store it in the refrigerator or an airtight container. Offer small amounts twice a day, and sprinkle the food with a vitamin supplement, available at a good pet store.

An outstanding book for anyone with an iggie is "Iguanas for Dummies" by Melissa Kaplan ($19.99, Hungry Minds Inc.). I've known Melissa for years, and I've always relied on her for my iguana information. She's also behind the best reptilian Internet site around, www.anapsid.org.

QUESTIONS FROM THE PACK

Q: Do you know whether a dog's mouth is generally cleaner than a human's? I have heard it said that a dog will lick a sore and that will help heal it. And some people say that a dog's mouth is cleaner than a human's. Are these old wives' tales? -- J.F., via e-mail

A. I brush my teeth two or three times a day and visit the dentist every six months for a thorough cleaning. My oldest dog, Andy, gets his teeth brushed a couple of times a week (if he and I are in the mood for it) and has his teeth cleaned annually. My younger retrievers have never had their teeth brushed or cleaned, although they do have them examined annually by our veterinarian. (Small dogs like my Andy, a Sheltie, are more prone to tartar buildup and usually need more dental care than do larger ones.)

All of my dogs (and most dogs I know) cannot pass up any opportunity to munch on the solid contents of cat boxes, or eat any other kind of poop, rotting food or other disgusting item they find on walks.

I don't know about you, but I wouldn't put any money on the superior cleanliness of the canine mouth. And I wouldn't allow the tongue of my dog near an open cut. Yuck!

Q: I have a cat who had a litter recently. Three are black and white (as she is), one is a calico female, and the other is a calico male. Is this a kitten I should give away? I know male calicoes are rare, and most are sterile. But with the rarity, should he go to someone who breeds cats? -- M.C., via e-mail

A: Like all of your kittens, he should be placed into a loving home and be neutered. (Make sure the momma is spayed, too, so she won't be contributing further to the pet overpopulation problem.) Male calicoes and the genetically similar tortoiseshells are indeed rare -- about one in every 3,000 of these cats is male -- but have no value to a breeder.

You can't breed a male calico and get more male calicoes for a couple of reasons. First, you're right in your understanding that male calicoes and torties are often sterile. Second, they're not "normal" males but are genetic oddities whose uniqueness cannot be passed along.

Male calicoes and torties are what's called "Klinefelter" males, and have both the Y and X chromosomes of normal males, plus a bonus -- an extra X. The two X chromosomes are what allow the calico or tortie pattern to be present, while the XY combination is what allows these cats to have male attributes.

The person you place the kitten with will have a wonderful companion and a bit of a conversation piece, but nothing beyond that.

Gina Spadafori is the award-winning author of "Dogs for Dummies," "Cats for Dummies" and "Birds for Dummies." She is also affiliated with the Veterinary Information Network Inc., an international online service for veterinary professionals. Write to her in care of this newspaper, or send e-mail to writetogina(at)spadafori.com.

4520 Main St., Kansas City, Mo. 64111; (816) 932-6600

The dogs and I just finished a six-month stay on the Gulf Coast of Florida, south of the now-famous (or should that be infamous?) city of Tallahassee. We endured the largest collection of news media since the O.J. Simpson trial, spring storms that took out trailer parks with startling regularity, and tourists who insisted on walking the stretch of beach we came to think of as ours and ours alone.

Make no mistake: We had a wonderful time. The retrievers, especially, believed the place to be paradise and spent as much time as possible dripping wet.

Still, there is no place like home. So when the cheap winter lodging rates ended, I packed up the van and drove back to Northern California -- where I haven't stopped sneezing and wheezing since. First stop: my doctor.

Although there are allergists who refuse to treat people who won't dump their pets, I've been fortunate over the years to find those who are willing to work with me. Because of them, I've been able to lead the life I want, even though I've always been allergic to animals.

Many animal lovers have the same problems I do. For them, my advice starts with finding an allergist who doesn't greet you with, "First, find new homes for your pets." In some cases, that will unfortunately be the ultimate resolution of the problem. But it needn't be the starting point for attacking animal allergies. It's your life, after all.

Here are some other tips for living with animals and allergies, recommend by allergists and field-tested by yours truly.

-- Don't neglect your other allergies. Controlling them may give you enough "breathing room" to make life with your pets bearable. Remember always that allergies and asthma are serious health problems, not to be taken lightly.

-- Don't go it alone: Find a doctor who will help you, pets and all.

-- Establish your bedroom as an "allergy-free zone." More than one-third of our lives is spent sleeping, and it's important to make that time less stressful for the body.

Close off your bedroom and reduce dust-collecting surfaces by removing carpets and rugs, wall hangings, stuffed animals and collectibles from the room. Invest in an air cleaner, and keep air ducts and ceiling fans clean. Banish feather pillows and down comforters. Use zippered, dustproof covers on the mattress and pillows. Combat dust mites by washing bedding frequently in hot water.

Make the bedroom completely off-limits to pets at all times. Although there's not a pet lover alive who doesn't enjoy a purring cat on the bed, keeping the bedroom allergy-free is probably a necessary compromise for allergy sufferers.

-- Try to limit exposure to other allergens. Avoid cleaning solutions, cigarette smoke and strong perfumes, and consider using a mask when doing yard work and housework, especially at the height of the pollen season. Better yet: Let someone else mow the lawn and do the vacuuming.

-- Keep your pets clean and well-groomed. The best situation is for a nonallergic member of the family to take over these pet-care chores. Weekly bathing is a must -- for cats as well as dogs. For cats, you don't even need to use soap. A rinse with clear water has been shown to be just as effective in keeping down allergen levels.

I spent the first few days at home thinking that only fresh ocean air would do the trick for my sneezing and wheezing, but then my allergy-control plan kicked in and the situation improved dramatically. Besides, the Gulf Coast may be paradise for part of the year, but the hot, humid summers are tailor-made for mold that is just as difficult for me to deal with as is pollen.

The dogs may miss the beach, but I will be thankful for the dry California heat, just as soon as the pollen levels drop.

PETS ON THE WEB

Will this be the year California finally legalizes the keeping of ferrets as pets? Chances are looking better than they have in years that this ridiculous ban will be lifted. Ferrets are legal pets almost everywhere else -- Hawaii is the only other state that prohibits them. And even with the ban, California ferret-fanciers estimate that more than half a million of the domesticated weasels live in the Golden State.

Californians for Ferret Legalization is a group at the heart of the fight, and their Web site (www.ferretnews.org) is full of information on their struggles. If you love ferrets, it's worth a look. If you're a California ferret-fancier, now is the time to step up and be heard. The Web site offers tips on how to contact the right decision-maker and the most effective way to do so.

THE SCOOP

Ferret fans have specific terms for their pets, starting with "hob" for an unneutered male ferret and "jill" for an unspayed female. Babies are called "kits," and the correct terms for altered adults are gibs (males) and sprites (females). Most charming of all, a group of these playful pets is called a "business" of ferrets (although some people use "busyness" instead).

QUESTIONS FROM THE PACK

Q: We got a Viszla puppy recently, and her breeder said it's very important that we get our pup into a puppy class for socialization and early training. But then we took Sasha to our veterinarian, and she said we should keep our puppy away from other dogs until after she has had her last puppy shot (at 4 months). Who's right: the breeder or the veterinarian? -- P.O., via e-mail

A: Both of them, really. Your breeder is right that it's essential for your puppy be socialized, and that a well-run puppy class is the best place to get your new family member off to the best possible start. And your veterinarian is also correct in saying that your puppy needs to be protected from disease until she is fully immunized.

Fortunately, you can protect your puppy from disease and still socialize your pet in a puppy class. That's because good puppy classes present minimal risk of contagious disease to the canine participants.

Whoa! I can already see readers stopping on the phrase "minimal risk." Perhaps I'd better say "acceptable" risk. Or even "comparable" risk, if you'll follow along to find out why.

There's nothing as important in a dog's life as getting off to a good start in terms of training and behavior. Dogs end up homeless because of poor behavior, and many such problems can be traced to a puppyhood without the proper training and socialization. It's always easier to prevent a behavior problem than to fix one, and that's why puppy classes are worth that "minimal" risk.

If you look at it from a lifetime perspective, a dog is more likely to die from behavior problems than from disease. A pup's best chance at becoming a well-loved member of a family rests heavily on how easy that animal is to live with over time. The adorable puppy who grows into an out-of-control or aggressive dog is a solid candidate for a trip to a shelter, where he'll be unlikely to land a second chance.

Puppy classes teach youngsters how to get along with other dogs, be handled by any number of people, and learn the basic lessons of good behavior, from sitting on command to keeping all four paws on the ground when greeting people. A good puppy class uses positive techniques to teach puppies that learning is fun and people are good. And that's a lesson for life.

While puppy classes are fine, heed your veterinarian's advice and keep your pup away from other areas where other dogs frequent, such as parks. It's fine, though, to set up play dates in secure yards that have been inhabited by healthy dogs who are known to be up-to-date on their vaccines. The dogs of your friends and family are great for these socializing get-togethers, as are the children. The more your puppy is safely exposed to, the better.

Q: Please settle an argument for me. Do cats need baths? -- G.K., via e-mail

A: Not usually. Most healthy cats do a fine job of keeping themselves clean and well-groomed.

If you have someone in your home with allergies, a weekly dousing with cool, clear water can help. Otherwise, your cat can stay bath-free unless he gets into something he can't get out of without a little help from some soap and water.

Brushing is probably more useful than bathing for helping to keep your cat in fine shape, especially for longhaired animals. The silky coats of some longhaired breeds is too much for a cat to handle, and brushing regularly is necessary to keep that glorious fur clear of mats.

Gina Spadafori is the award-winning author of "Dogs for Dummies," "Cats for Dummies" and "Birds for Dummies." She is also affiliated with the Veterinary Information Network Inc., an international online service for veterinary professionals. Write to her in care of this newspaper, or send e-mail to writetogina(at)spadafori.com.

4520 Main St., Kansas City, Mo. 64111; (816) 932-6600