Alternative Sources of Livestock Bedding

Iowa State University, Northwest Research Farms and Allee Demonstration Farm ISRF05-29, 31
Absorbency of Alternative Livestock Bedding Sources
Reggie Voyles, undergraduate research intern
Mark Honeyman, professor
Department of Animal Science
As the demand for niche-marketed meats
increases, so does need for research in this area.
One niche market that is being examined is pork
raised in deep-bedded systems. There is also a
call for alternative bedding materials. Farmproduced
bedding sources such as cornstalks
and various types of straws are commonly used.
However, this study looked at other possible
materials. Products were tested to see if they
could be equal substitutes based on their
absorbency. A ground lumber product and a
ground lumber with drywall product with a ratio
of 8:1 lumber-to-drywall were tested. These
products were produced from demolished
buildings. They had different performance
qualities than wood shavings and were
compared to cornstalks, recycled paper, oat
straw, and triticale straw.
Materials and Methods
The trials were conducted at the Iowa State
University Ag Engineering and Agronomy
Farm, Boone, Iowa. Samples of cornstalks,
recycled paper, oat straw, triticale straw, ground
lumber, and a ground lumber/drywall mixture
were collected. The Taylor Recycling Facility of
Iowa, LLC, donated the two ground lumber
samples. The rest of the samples were collected
from various Iowa State University research
farms. Once the samples were collected, they
were tested for absorbency. The process used
was taken from an article found on the Ministry
of Agriculture and Food of Ontario, Canada’s
website. The steps were:
1. Place 1 lb of the bedding material in one leg
of pantyhose, weighing both the pantyhose
and bedding material.
2. Place the material in a five-gallon pail of
water and leave it completely immersed for
24 hours. Make sure that there is enough
water so that some free water is left after the
24 hours has ended. Covering the pails cuts
down on the chances of water evaporation.
3. Take the bag out of the water and hang it to
drain, but only until it has stopped dripping,
not so long that the sample has started to dry
4. Reweigh the material and calculate the
absorbency factor from the following
Absorbency factor = (weight after
soaking – original weight)/original
Five replications of this process for each of the
six bedding type were completed. Each sample
was soaked in a bucket for 24 hours and then
hung to drip for 75 minutes, the time that it took
for the sample to quit dripping. After it had
finished dripping, the sample was reweighed to
calculate its absorbency factor as a bedding
Results and Discussion
The absorbency means of the five replications
of the six bedding materials are shown in Table
1. The means shown in Table 1 were compared
using the Tukey’s test for mean separation
(P<0.002) with SAS. The data collected show
some differences in the absorbency of the
different bedding materials. There were three
pairs of bedding based on absorbency: a top,
middle, and bottom pair. The greater the
absorbency factor, the more water the material
held. Cornstalks and oat straw each held about
three times their weight of water. The samples
of shredded paper and triticale straw each held
about two times their weight of water, while the
ground lumber and ground lumber/drywall
Iowa State University, Northwest Research Farms and Allee Demonstration Farm ISRF05-29, 31
mixture held only just over their weight of
After knowing their absorbencies, these
different bedding materials can be placed in a
usage schedule. Cornstalks and oat straw have
the higher absorbency, so it is recommended
that corn producers use harvested stalks as
bedding. The shredded paper is an option for
those who are close to a recycling center with an
abundance of this product available. The lumber
products can be used if there is a shortage of
cornstalks or straw or to stretch the available
supply of bedding materials. They also might
make a good base for a bedding pack, because
of their durable structure when wet. The lumber
products absorb just like the others; it just takes
more bedding to absorb the same amount of
The authors gratefully acknowledge the
following people for all of their help and
encouragement throughout this project: Arlie
Penner, Mike Fiscus, Wes Rodgers, and Seth
Schroeder. The project was supported by the
Agronomy/Baker Endowment and the Leopold
Center for Sustainable Agriculture.
Table 1. Mean absorbencies of six bedding types.
Materials Mean absorbency factor
Cornstalks 2.70a
Shredded paper 2.08b
Triticale straw 1.97b
Oat straw 2.86a
Shredded lumber 1.15c
Shredded lumber plus
(lumber/drywall, 8:1)
Means with different superscripts differ (P<.002).