Wood shaving are suppossedly linked to liver problems in rabbits
"Did you know that commercial pine or cedar litter or bedding can be VERY DANGEROUS and sometimes fatal to rabbits, rats, mice, guinea pigs, etc.?? Did you know that sand and clay kitty litters can cause and/or aggravate respiratory problems? Read on.
SOFTWOOD BEDDINGS: PINE AND CEDAR LITTERS
In 1989, House Rabbit Society (HRS), the premier national rabbit rescue organization, made a curious discovery (Harriman 8-9) following the unfortunate death of a young, healthy rabbit after a routine spay operation. HRS ran blood work and discovered that the rabbit's liver enzymes were far higher than normal. Excess liver enzymes in the blood indicate leakage from the liver, which is not handling toxins adequately; a defective liver cannot properly filter anesthetics, or other toxins.
Originally HRS had advised that all rabbits over two years old have blood tests run on them prior to any surgery. Because they could find no cause for the above rabbit's death they lowered that age recommendation to 18 months. As they began testing ALL rabbits prior to surgery, a disproportionately high number of rabbits showed elevated liver enzymes. Thus began a long process of elimination.
SEARCHING FOR A CAUSE
http://www.mybunny.org/info/litterliver.htm
After searching through all sorts of data (breed, body type, age, weight, etc.), no common factors were found. They finally looked to the bunny home—the cage—for clues, and that is where they found their answer: all of the rabbits who had elevated liver enzymes were using pine shavings in their individual litter boxes and/or cage trays! Of the group of rabbits tested only those that used alternative litters were found to have normal blood panels. "