can cause discoloration of animals. This bedding is primarily used with larger animals as non-contact bedding.
Reclaimed paper is a by-product of other paper processes.
This is a more expensive product than recycled paper due
to the processing involved, but provides a comfortable
Virgin paper is paper that is produced specifically for
bedding. It is low in contaminants and consistent in size
and shape. It is virtually dust free, and the most expensive
of the three types.
Blended beddings incorporate enrichment and/or nesting materials with
bedding. They may combine wood,
cob and even paper with nesting
material, or include two different
beddings. These beddings ensure
that each cage has enrichment or
nesting materials without having to
handle cages twice, so there can be a
labour savings. Since the enrichment/
nest material is combined with an absorbent
bedding material, the animals remain comfortable and dry.
BEDDING AND CAGING
There have been a number of studies discussing ammonia in static versus ventilated caging, and the caging
system used must be considered when selecting bedding.
All beddings contain some dust, and the dust can lodge
in ventilated racks, especially in the exhaust ducts. This
may cause interruption in the air flow needed to keep the
bedding dry and increase equipment maintenance. With
extended change cycles, very white bedding may appear
dirty, even though the animals remain comfortable and dry.
Dusty bedding may also cause respiratory problems. If the
caging includes an automated water system, the size of the
bedding particle is important as very small wood chips
and smaller cob sizes have been known to lodge in the
drinking valve, causing cage flooding. This is especially a
concern with mouse strains that actively “housekeep”.
BEDDING, NESTING AND ENRICHMENT
Many common research animals will make a nest when
appropriate nesting materials are available.According to the
Guide, contact bedding expands the opportunities for species specific behaviours including foraging, burrowing and
nest building. In sufficient quantities, it also supports ther-moregulation. When the animal rooms are colder than mice
would prefer, they will huddle together for warmth and
added bedding will help to maintain body temperature. This
is a particular consideration for nude and hairless animals.
For some animals, nest-building is a reaction to breeding;
for others, nesting is just a normal activity. Observing mice,
you can also note how much time animals spend tending their nest — rearranging and cleaning both the nest
and surrounding area. Nesting materials allow animals to
engage in specie specific behaviour.
OTHER BEDDING CONSIDERATIONS
According to the Guide, some beddings and nesting mate-
rials are preferable to others and animals may show a clear
preference. It also states that when provided with pre-
ferred nesting materials, animals will construct larger nests.
An interesting fact is that rats are not spontaneous nest
builders, but instead learn to use nesting materials. When
rats are exposed to nesting materials as young animals,
they learn to use them and prefer to use the same mate-
rials for later nesting.
While not exactly bedding, but certainly related,
some animals require dust baths. Not only are dust
baths important for the animal’s fur condition, they
are a natural behaviour, therefore also serve as enrich-
ment. Dust baths are sold under a number of brand names,
but the composition is primarily a fine, absorbent clay and
works by removing oil and dirt from the fur.
Bedding storage is important to consider. Bags should be
stored off the floor, away from the wall, so that air can
properly circulate. As with feed, care should be taken to
protect bedding from vermin and insects. Check with
your bedding supplier to determine their specific quality
Each bedding type has properties that either help with
mechanical dispensing or cause difficulties. Free flowing bedding, such as corncob and wood chips, dispense
well, due to the weight and consistent size of the product. Some paper and wood flake products are difficult
to dispense due to static electricity, dust and bridging in
waterfall type dispensers.
The bedding selected can affect animal behaviour and
also affect research results. So when selecting a bedding
consider a number of factors; such as animal type, caging
type, research goals, the presence or absence of automatic
watering. The right choice will be visible in your animals
and your research.
Deb Benner is the owner, president, and general man-
ager of Animal Specialties and Provisions. She has over
30 years of experience in the laboratory animal sciences
marketplace. Contact Deb at email@example.com.