|
A Pacific Northwest Extension Publication
Oregon State University, Washington State University, University of Idaho
Designing Dairy Free Stalls
PNW 321
Reprinted January 1993
M.J. Gamroth and J.A. Moore
Do you want to print a copy?
We recommend downloading the print version (185 K).
First download the free Adobe
Reader, if you don't already have it.
Size
Table 1--Recommended stall sizes
Free stall base materials
Figure 1--Tire surfaced concrete free
stalls
Figure 2--Tire
surfaced concrete free stalls
Bedding
Figure 3--Cow mattress
Stall dividers
Withers bar or cable
Figure 4--Diagram of free stall
Your cow's "space envelope"
Brisket boards
Curbs
Cow-to-stall ratio
Management
It was about 1960 that Adolph Oien remodeled his Stanwood,
Washington, loafing barn, installing the first free stalls. From
this Pacific Northwest beginning, these "individual beds"
for cows have become the most popular kind of cow housing.
Different designs work well on different farms. Some
operators like stalls with a concrete base; others don't. Some
use separated manure solids for bedding; others report increased
mastitis when using them.
The common thread in successful free stalls-as in milking,
feeding, and breeding-is good management. Careful thought in
design and regular maintenance are keys to satisfaction.
A recommendation for one "best" design is impossible
because of the great differences among farmers, their objectives,
their management styles, and their farms. The following recommendations
have been gathered from many successful operations.
top
Size
Stalls must be large enough to provide a comfortable
bed and adequate room for cows to rise. As animals get larger,
so must the free stalls.
Table 1 lists recommended stall sizes for dairy cattle.
It is adapted from infor- mation reported by Cornell University,
the Midwest Plan Service, and Oregon State University.
The width is center to center on 2-inch dividers; the
length is outside of the back curb to the front wall or partition;
and the height is from the bedding to the top of stall dividers
or withers bar measured at the front of the stall (add about
3 inches at the back of the stall).
top
Free stall base materials
Tamped soil, heavy in clay, is common as a base under
bedding. It must be packed solidly before applying bedding and
will need semiannual maintenance to fill holes and restore slope
from front to back.
A gravel or sand base will improve drainage under bedding-but
these don't pack well, so maintenance must be increased. Both
will be kicked out into the alley, causing problems in a liquid
waste handling system.
Soil, gravel, or sand should fill the stall to within
2 inches of the top of the back curb. The curb will help retain
bedding. Avoid curbs that stick up more than 2 inches. Cow injuries
can result, especially with square-edged curbs. Inside curb edges
should always be sloped or rounded.
Three inches of concrete can replace the base material.
It should be even with the curb at the back of the stall for
proper drainage. Use some bedding on the concrete.
Pipes or boards fastened at the rear of the stall to
retain bedding are not recom- mended. They require additional
maintenance, they can cause injuries, and they can reduce moisture
drainage from bedding on the rear surface of the stall.
Concrete reduces maintenance and bedding costs, but more
cow injuries are reported, and cows use concrete-based stalls
reluctantly if other base materials are available.
Burying used tires in stalls will reduce the amount of
bedding and base material kicked into the alley:
- Drill large holes in the bottom walls of the tires for
drainage.
- Place the tires horizontally on packed clay.
- Fill them both inside the "bead" and outside
with soil or sand to prevent cows from working them out.
Researchers from Washington State University recommend
installation according to figure 1.
One operator has placed a quarter of a tire (split lengthwise
and then in half) in the fresh concrete poured in free stalls,
placing the bead just above the concrete. The tires in the concrete
are softer and warmer for cows than bare concrete and they have
cut bedding use in half.
top
He placed the tops of the curves toward the front of
the stall so they don't collect unwanted moisture (figure 2).
The tire-concrete combination has been in use over 5 years, and
very few tires have loosened.
The average slope of all base materials should be between
3 and 4 inches from front to back of the stall. Cows prefer lying
uphill. The slope is necessary for cow comfort, to prevent animals
from lying in the stall backwards, and to move moisture from
the top or front of the stall to the alley.
top
Bedding
Bedding is used to provide insulation and a cushion between
the cow and the base material and to absorb moisture. Sawdust
or shavings are the most common bedding in the Pacific Northwest.
Cereal grain straw works well, but it should be chopped
to increase absorbency, to make handling easier, and to reduce
plugging of manure pumps.
Separated manure solids can be used as a bedding material.
Stack them for at least 2 weeks and allow them to heat or compost.
This produces temperatures of 140°F and kills mastitis-causing
bacteria. During rainy months, compost them under a roof to attain
the bacteria-killing temperatures.
Once composted, store them outside under plastic cover
so the bedding is not excessively wet when you spread it in the
stalls. Don't cover a fresh stack with plastic-it will reduce
or stop the composting process.
Rubber mats fastened over a base material have been used
to replace bedding, but they have some disadvantages. Cows prefer
lying on other materials and adapt very slowly to the mats. They
are slippery when wet. Bedding placed over them will
reduce these disadvantages, but then you save little on bedding
costs.
"Cow mattresses" are being tried in some western
Washington dairies. These are made of sturdy, woven plastic material
wrapped around conventional bedding and fastened to the front
of the stall. They look promising in keeping cows clean and dry, and in saving bedding. A cross-section is shown in figure
3.
top
In a recent Oregon study, the average cost of bedding
was $13 per cow per year. Labor costs for chopping, hauling,
and filling are not included in this average.
Straw and separated solids had low material costs, but
they may take more labor. One farmer purchased newspaper from
a local service organization, chopped it, and bedded for $12
per cow per year.
Hydrated lime applied to the bed-ding near the back of
the stall will reduce bedding moisture. Because it reduces the
moisture level and raises the pH, it may reduce mastitis. Apply
at least 1 pound to the bedding surface in the rear of each stall
when you add or stir bedding.
top
Stall dividers
Divider design and performance varies widely on dairy
farms. About half are made of wood, and half of metal. Pipe-loop
stall dividers are gaining popularity. Look for sturdy dividers
that require little maintenance and that you can remove easily
in an emergency or for repair.
One divider that provides strength and removes easily
is a heavy pipe loop that slips into a larger pipe sleeve, which
is poured into a concrete head wall. You remove it by pulling
a pin out of the sleeve and loop and slipping out the stall divider.
Loop dividers average 69 inches long. This is proper
for stalls up to 84 inches long. The outside of the curb should
not extend more than 15 inches beyond the end of the divider
or be lower than 14 inches at the curb, to discourage animals
from walking over dividers or standing along the curb at the
rear of the stalls.
Spring-loaded loops offer some advantages over regular
loops in cow comfort and maintenance. However, there are complaints
that cows learn they can move them and begin lying almost underneath
the dividers. Like regular loops, they require very stout lumber
or concrete for attachment.
Repairs are higher for pipe loops than for dividers attached
at the curb and the headboard. However, there's no attachment
in the rear curb to rust off or be damaged by equipment that
scrapes alleys.
Completely rusted pipe or angle iron is a major disadvantage
of metal dividers fastened at the curb. Filling the pipe set
in the curb with concrete extends service life, but corrosion
of metal exposed to manure and urine is inevitable.
Placing a heavy PVC pipe "boot" in the concrete
curb and slipping the divider support within that during installation
may reduce corrosion, extending the life of the metal divider.
The height from bedding to the bottom of a divider near
the back of the stall should be 12 to 18 inches to prevent injury
to hips and pins of animals. A board in the base material, running
parallel with and immediately under the divider, reduces bedding
requirements and the need to rake bedding into hip and leg holes
created by cows.
top
Withers bar or cable
Placed above the divider to meet the cow's shoulders
or withers, a withers bar or cable should discourage cows from
lying too far forward in a stall and encourage backing out when
standing up.
The average distance back from the headboard should be
18 to 20 inches, or 60 to 66 inches from the outside of the rear
curb. You'll need to adjust the bar to fit your cows and stall
length. The height of the bar or cable from bedding is included
in table 1.
Use pipe, cable covered with PVC pipe, electrified wire,
1/2 inch rebar, or wood. The PVC-covered cable is durable
and avoids the injury to cows' necks that's possible with uncovered
cable or wire.
Pipe--clamped, welded, or bolted to the dividers--makes
stalls more rigid. This is an advantage with lighter-gauge pipe
loop dividers. Removal for downer cows is still practical with
clamped or bolted withers bars.
A new method to reduce injury when cows get up is the
"floating" withers bar. It's hinged on the stall dividers
to swing up when pushed from below as a cow gets up.
Some operators run the bar over four stalls. This provides
some weight, but it doesn't make one cow raise the bar the entire
barn length. Figure 4 shows one design of the floating bar.
top
top
top
Brisket boards
These prevent cattle from moving too far forward in stalls
while lying down. They're usually placed 20 to 24 inches from
the headboard or about three-fourths of the stall length from
the rear curb. Most are made of wood, are set at an angle toward
the headboard, and stick out about 4 inches beyond the base material.
They should flex slightly when bumped by the cow.
The cow's head will fit comfortably over the brisket
board into the front of the stall, but the board will keep her
body from coming forward.
Because the top of the brisket board is slightly higher
than the bedding level in the stall, extra bedding can be stored
in front of it and raked back to the laying area as necessary. Curbs
Curbs at the back of the stall should be concrete. It's
desirable to keep the base material even with the inside curb
to promote drier bedding in the rear of the stall.
A tall curb (10 to 12 inches) will reduce manure in the
back portion of the stall, whether you scrape or flush animal
wastes. If the edges of the curb are rounded, cow injuries will
be limited even with the tall curbs. Cows have no trouble stepping
into or backing out of a 12-inch high stall.
topCow-to-stall ratio
Since dairy cattle spend 10 to 14 hours daily lying down,
it's ideal to have one stall for each cow. This may not be practical.
Northwest dairy operators are having no problems with 10 to 15
percent more cows than stalls. The ratio is an operator preference and is not related to other design factors.
Management
Good management and individual preference are the keys
to satisfaction and performance of individual stall designs:
- Remove manure at least once daily.
- Replace wet bedding promptly.
- Repair broken dividers as you find them.
- Restore the base material to its original slope at least
every 6 months.
After building or modifying stalls, spend time watching
the cows use them. Do they lie where you want them? Can they
get up easily? How much bedding are you using?
If 3 to 5 percent of the cows are reluctant to use the
stalls after 2 weeks, there could be a flaw in the design or
in your management. Using ample bedding will ease the transition
to new facilities.
Visit other dairies to see what works before you make
changes. Most operators are willing to share their experiences
with you. Your Extension agent can provide you with ideas that
other operators have found successful and can identify operators you should visit before you change your system.
top
Prepared by Michael J. Gamroth,
Extension dairy specialist, and James A. Moore, Extension agricultural
engineer, Oregon State University. This publication prepared
in cooperation with Extension specialists at the University of
Idaho and Washington State University.
Reprinted
January 1993.
|
