In response to James Kramer's question about cedar shavings:
 
        This got to be a little more than a simple answer, once I started
looking into it.
 
 
        (The following short article may be reprinted by anyone desiring to
disseminate this information in a newsletter or non-commercial publication.
This material may not be altered or changed in any way.  Under Title 17 of the
U.S. Code, Section 105, copyright protection is not available for any work of
the United States Government.)
 
       WHY NOT CEDAR SHAVINGS?
 
        For years, cedar shavings have been used as bedding for many species of
small mammals including ferrets.  Over the last ten years, increasing evidence
is cropping up that this may not be a good choice.
 
        Cedar shavings, as well as other aromatic soft woods, such as white and
yellow pines, release volatile hydrocarbons which affect those animals living in
them.  Plicatic acid, a volatile hydrocarbon, results in asthma in humans and
rabbits. Other hydrocarbons result in changes in the liver, which may impair its
ability to detoxify certain drugs, including various anesthetic agents.  Cedar
shavings have also been incriminated in increased mortality in rat pups, and
various scientists over the years have alluded to possible carcinogenicity.  In
chicken litter, cedar shavings harbored more bacteria than other types of
litter.
 
        On the more practical side, a 1986 article in Lab Animal evaluated many
of the common bedding materials, also including hardwood chips, sawdust, paper
chips, newspaper, ground corncob, rabbit pellets, straw, and hay (along with
several others) for the following:  absorbency, dust, endogenous effects on the
animal, cost, use in nesting, and disposability.  In all categories, cedar
shavings was not recommended.  Interestingly enough, paper products and
heat-treated softwood chips scored highest overall.
 
        In my experience, ferrets are happiest in old sweatshirt or towels,
which rarely cause problems.  Beware, however, the bored caged ferret, who may
ingest parts of these items for lack of other stimulation, and obtain a
gastrointestinal foreign body in the process.
 
References:
1.  Weichbrod RH et al.  Selecting bedding material.  Lab Anim.  Sept 1986, pp.
25-29.
2.  Kraft LM.  The manufacture, shipping, receiving, and quality control of
rodent bedding materials.  Lab Animal Sci.  1980 pp. 366-372.
3.  Weichbrod RH et. al.  Effects of Cage Beddings on Microsomal Oxidative
Enzymes in Rat Liver.  Lab Animal Sci.  38(3):  296-298, 1988.
4.  Hessler, JR.  Design and Management of Animal Facilities.  In Laboratory
Animal Medicine, JG Fox, ed.  Academic Press Inc, Orlando.  1984.
5.  Chan H. et al.  A rabbit model of hypersensitivity to plicatic acid, the
agent responsible for red cedar asthma.  J Allergy Clin Immunol 79(5) : 762-767.
[Posted in FML issue 1071]