By: ASPCA ANI-MED

Let's talk about bedding. Not comforters, pillows and sheet sets, but the materials that you'll use to line the bottom of your little critter's cage. To be effective, bedding should keep your pet warm and dry, while absorbing waste materials. But it must also be safe, dust-free and non-toxic. Unfortunately, some materials traditionally used for bedding can make your little guys sick.

You may have heard recent warnings about cedar and pine shavings. Heed them, please! Although these materials are readily available at pet supply stores and have been used as bedding for small animals for years, responsible pet owners are better informed these days. Both cedar and pine contain volatile phenols and acids that can irritate and damage an animal's respiratory tract. In fact, research has shown that these acids can kill the cells that line a critter's lungs.

Toxins from cedar and pine shavings have also been implicated as the cause of liver damage, particularly in companion ferrets and rabbits. And constant exposure to toxic compounds can severely stress an animal, thereby weakening his immune system. Pine and cedar may smell good--but unfortunately, that's about all they have to offer your little guys.

Luckily, there are many safe, effective alternatives that work great: * Aspen shavings will not harm your pet, and are relatively inexpensive. You may find they aren't as effective at controlling odor, so you'll have to change the bedding more frequently.

* Caretakers of little critters sing the praises of pelleted beddings made from a variety of materials, from wood pulp and recycled paper to plant fiber. Dust-free, highly absorbent and great at odor control, pelleted bedding is an excellent choice. You'll have a variety of brands from which to select.

* Fresh straw and hay will work, too, particularly for rabbits and guinea pigs. We've also had reports about the merits of rabbit food and alfalfa pellets used as bedding for rats, mice, hamsters and gerbils. These materials are both inexpensive and absorbent.

If your little friend likes to make cozy nests for napping, you’ll need to provide supplies for him. Hamsters, mice and rabbits are big nesters, and will appreciate straw, hay and shredded napkins or paper towels with which to sculpt sleeping areas and hiding places. Do not give your animal cotton wool bedding that you may see in pet supply stores. If ingested, it can get lodged in an animal's throat or intestine, and has been known to become impacted in hamsters' cheek pouches.

No matter how effective a bedding is at controlling odor, you'll still need to change it regularly. It's a good idea to remove soiled bedding at least once a week. And remember, most litters work most efficiently if you use just a thin layer on the cage floor. If you have gerbils, however, your little guys will appreciate a bit extra for digging and burrowing.