Guinea pigs are cute and cuddly companions who tend to live between five and seven years. They like to have fresh bedding lining their cages, and for many owners that means wood shavings. However, some wood can be toxic to your pet, so check the label carefully to make sure it's strictly hardwood.
Ah, the fresh smell of cedar that keeps the room from smelling like guinea pig urine. Unfortunately, that smell that you consider fresh is made by chemical compounds called phenols that are being released into the air. Long-term exposure to these phenols is linked to chronic respiratory and liver problems. Your guinea pig's nose stays right up on the wood chips most of the day, meaning she's breathing in those phenols at close range without a break. Although no studies definitively show that cedar shavings should never be used, the general consensus is that they are toxic enough to be avoided.
If you sniff the pine shavings and they smell like a freshly cut Christmas tree, those shavings are also releasing phenols. That bright, crisp smell is the chemical compound evaporating from the wood. Kiln-dried pine shavings are considered safer for your guinea pig since the high heat quickly sucks away any remaining moisture—and the chemicals along with it—but avoid air-dried shavings, which that often smell stronger.
Never use sawdust from any type of tree as bedding for your guinea pig. The fine dust that comes along with it flies up every time your guinea pig moves, and that dust can clog her airways or leave her vulnerable to respiratory infection. While it's not exactly toxic, it's still dangerous to use as bedding.
Guinea pigs need to gnaw often to keep their teeth ground down to a reasonable size, and wood is the ideal solution. Avoid cedar and pine branches for the same reasons you shouldn't use them as bedding. However, branches from hardwood trees such as oak, maple, elder and willow are safe to give your pet. Make sure the wood hasn't been treated with chemicals such as pesticides, which can poison your guinea pig.
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