Freestall Barn Configurations

Cow Comfort Issues in Freestall Barns

Roger Palmer

Associate Professor and Extension Specialist

Dairy Science Department

University of Wisconsin-Madison

Brian Holmes

Professor and Extension Specialist

Biological Systems Engineering Department

University of Wisconsin-Madison

Large scale dairies have become very popular in the past decade because of the adoption of new

housing styles and the development of new production-enhancing technologies. These technologies

allow producers to enhance labor efficiency, increase profits and improve the quality of life for both

dairy owners and workers. The challenge to the managers of these modern large dairy herds is to

economically achieve high milk yield without sacrificing animal health and welfare, deterioration of

the environment, or human safety. The freestall barn has increased in popularity as a housing unit

for cows and heifers throughout the industry. Properly designed and managed freestall barns

provide a convenient method of managing dairy cattle and providing a comfortable living

environment for those animals. This paper concentrates on design factors that emphasize cow

comfort.

Freestall Barn Configurations

Freestall barns can be arranged in a variety of patterns, each of which has benefits and limitations.

These tabled are patterned after those of Graves, 1995.

Two rows of freestalls with manger on one side

Benefits

Limitations

Adequate manger length for all animals to eat at

one time

Higher draftiness in open-front versions

Adequate manger length to use self-locking

headgates

Difficult to fit some sites for large herds

Narrow barn provides improved natural

ventilation

May require more outside or covered lanes to

access the parlor

Convenient manure removal

Feed may be exposed to precipitation

Convenient drive-by feeding

Easy expansion

Animals protected from sun, wind & precipitation

Low cost per stall for unroofed drive

Three rows of freestalls with manger on one side

Benefits

Limitations

Narrow barn provides improved natural

ventilation

Not all animals can eat at one time

Convenient manure removal

Inadequate manger length to capture all animals

in self-locking headgates

Convenient drive-by feeding

Higher draftiness in open-front versions

Easy expansion

Difficult to fit some sites for large herds

Animals protected from sun, wind & precipitation

Feed may be exposed to precipitation

Lowest cost per stall for unroofed drive

May require more outside or covered lanes to

access the parlor

Four rows of freestalls with drive-through feeding

Benefits

Limitations

Adequate manger length for all animals to eat at

one time

Wider barn may require higher side walls for

good natural ventilation

Adequate manger length to use self-locking

headgates

Highest cost per stall

Convenient manure removal

Convenient drive-through feeding

Easy expansion

Animals protected from sun, wind & precipitation

Convenient animal movement to parlor

Feed protected from precipitation

Six rows of freestalls with drive-through feeding

Benefits

Limitations

Convenient manure removal

Not all animals can eat at one time

Convenient drive-through feeding

Inadequate manger length to capture all animals

in self-locking headgates

Easy expansion

Will require taller sidewalls for good natural

ventilation

Animals protected from sun, wind & precipitation

Higher concentration of animals increases heat

stress (heat & moisture levels) when ventilation

rate is low in summer

Convenient animal movement to parlor

Feed protected from precipitation

Low to intermediate cost per stall

Stall rows perpendicular to ridge line

Benefits

Limitations

Can have more stalls per square foot of building

with alleys between rows only & outside feeding

May need to use outside feeding to have

adequate bunk length

May be a way to fit more animals into an

existing building

Manure removal not convenient

May be difficult to move animals by group to

parlor if crossover alley not provided

May have fewest stalls per square foot of

building if crossover alleys are provided on both

ends of freestall rows

Will be drafty in front stalls of open-front barn

Will have blind alleys if no crossover alleys

provided

Outside feed bunk exposes animals & feed to

sun, wind & precipitation

Two rows of freestalls with outside feeding

Benefits

Limitations

Narrow barn provides improved natural

ventilation

May have a blind alley at end of pen

Convenient manure removal

Manure removal from yard may be problematic

Easy expansion

Difficult to fit some sites for large herds

Lowest initial cost freestall barn

Animals & feed exposed to sun, wind &

precipitation

End of barn stalls may be drafty

Animal movement to parlor will be outside

Freestalls next to outside wall

(2-row tail-to-tail, 3-row, 4-row tail-to-tail, 6-row freestall barns)

Benefits

Limitations

More stalls per given barn length than face-to-

face

Sun & precipitation more likely to enter stalls

than face-to-face

Cows tend to prefer an outside row of stalls in

summer

More cows have to walk further to feed than

face-to-face

Timid cows not confronted from the front while

in stall

Outside row draftier in winter

Manure in alleys less likely to freeze than in

alley next to wall

Outside stalls need to be longer for lunge space

Outside rows of stalls may block wind for natural

ventilation

Face-to-face stall rows (2-row face-to-face, 3-row, 4-row face-to-face, 6-row)

Benefits

Limitations

Cows share head space – stall platforms shorter

Cows share head space – timid cows may avoid

confrontation

Waterers can be longer across two rows of

stalls

Animals tempted to lie down after milking

instead of eating/drinking – no ability to limit

access to stalls

Easier sidewall construction when no stalls near

wall

Fewer stalls per row for a given building length

in 2- & 4-row arrangements

More sidewall height can be opened when no

stalls near walls

Manure in outside alley may freeze more quickly

Less sun & precipitation in stalls when no stalls

near wall

Cows breathe into face of other cows (heat,

moisture & pathogen concerns)

Outside feeding

Benefits

Limitations

Low initial investment

Higher feed losses from precipitation, heating &

animal refusal

Higher heat & cold stress in animals,

contributing to reduced dry matter intake with

consequent reduction in milk production

Manure exposed to precipitation, contributing to

contaminated runoff

Worker exposure to weather

Inside feeding

Benefits

Limitations

Low feed loss

Higher initial investment

Low animal stress

No contaminated runoff

Weather protection for those working inside

(animal treatments, animal observation, manure

removal, etc.)

Freestalls

To support the high production levels expected of or modern dairies, facilities must be designed to

provide a comfortable place for cows to lie. Designs must also consider the initial and on-going cost

to maintain the stalls. These objectives often are antagonistic and the producer must select a design

that considers both criteria. Current research has shown stall usage increases with increased stall

size and the use of certain stall base materials. The task for the producer is to weigh the value of

the expected increased milk production, lower health costs, and/ or increased longevity in the herd

against the extra costs incurred.

Lactating Dairy Cow Daily Time Budget

Research by Grant, 2003, shows the daily time budget for a lactating dairy cow to include 10-12

hours lying, 3-5 hours eating, 30 minutes drinking and 2-3 hours during milking. High producing

cows have been shown to lie up to 14 hours per day and that for each additional hour a cow spends

resting an additional two pounds of milk per day can be expected. This is the main reason why

much of the current cow comfort research on stall size, divider design, and stall surfaces use the

amount of time cows spend lying as an indicator of cow comfort.

How big are your cows?

Cows will use comfortable stalls because correctly sized freestalls are easy for the animal to get up

and down and they have a comfortable surface to lie on. To support labor efficiency, stall size

should encourage animals to lie straight in the stall with their udder and legs completely on the stall

platform, but with their rump over the back of the stall so manure will fall in the manure alley and

not on the stall surface. The sizing of freestalls is determined by the animal‟s size and should be

built to accommodate the larger animals in a group. Anderson, 2003, has found that rump heights

and hook bone widths are useful to estimate several other body dimensions (Table 1). He suggests

that you determine the size of animals by measuring a large representative group of animals in your

herd and using data to estimate the following dimensions.

Body Dimension

Normal Cow

Dimension Relationship

Rump Height - Mature

Median 60”

Rump Height – Lactation 1

Median 58”

Hook-bone width

26”

Nose-to-tail length

102”

1.6 * rump height

Resting imprint - length

72”

1.2 * rump height

Resting imprint - width

52”

2.0 * hook-bone width

Forward lung space

24”

0.4 * rump height

Stride length when rising

18”

0.3 * rump height

Stance – front-to-rear feet

60”

1.0 * rump height

Wither (shoulder) height

60”

1.0 * rump height

Table 1: Body dimension, example measurements for mature Canadian Holstein, and ratios to

height and hook-bone width.

Cow Comfort

Although „cow comfort‟ has become a buzzword among dairy producers and professionals,

scientific research is limited. Recommendations for freestall dimensions vary widely and make the

decision on what to build very confusing. Weary and Cassandra suggests scientific research should

be based on three factors: 1. does the housing cause injuries to the animal: 2. what types of housing

do the animals prefer; and 3. how does the housing affect the animals behavior. In the following

pages we will attempt to site some of the current research relating to these issues.

Skin Lesions on the Hock

Mowbray, et al., 2003, showed that hair loss on the hock joint was affected by different stall base

types. When geotextile mattress covered stalls with 1.2” of kiln-dried sawdust bedding (mattress)

was compared with deep-bedded sand based stalls with 8” of washed river sand over a dirt base

(sand), it was found that skin lesion location changed. Hair loss and skin breakage was higher at the

hock joint for cows housed in mattress stalls and higher on the point of the hock for sand stalls. The

suggested cause for lesions is friction between the leg and the mattress surface, and contact with the

rear curb in sand stalls.

Freestall Design – Manure Curb Height

The key freestall dimensions to consider are curb height, stall width, stall length, neck-rail height,

and freestall divider mounting specifications. If curbs are too low, manure may enter the stall when

manure it being removed from the barn and if too high, cows will be reluctant to back out of the

stalls. A curb height of 10” is normally recommended, but often will be 9.5” if a 2”x10” plank is

used to form the curb. Some people advocate a lower curb height. For example, Cook and

Nordlund, 2004, recommends an 8” curb and moving the neck rail back the width of the curb to

force cows to stand in the perched position with sand based stalls. They are not concerned with

cows perching since their work indicates cows do not spend prolonged times standing half in and

half out of sand stalls and the elevation of the front feet will be less with the lower curb.

Construction of the manure curb differs for stalls filled with bedding materials (sand, manure solids,

lime, etc.) than from flat surface stalls that are covered with a cushion of some type (mattresses,

mats, waterbeds, etc.). Manure curbs for sand stalls normally are 4-6” wide and are used to hold the

bedding material in the stall. Since the level of the bedding material changes with the mount of

material in the stall, the manure curb is often chamfered in the direction of the cow to prevent the

cow from having to lie against the sharp edge when the bedding level is low. With flat surface

stalls the height of the added cushion needs to be considered. Having a 10” curb with a 4” mattress

in effect becomes a 14” curb. Most recommendations for this total curb height is between 8 and 12”

Freestall Design – Stall Base Slope

Normal recommendations have been to have stall bases constructed with a slope of 2-3% from the

manure curb to the brisket locator. This has been done because cows prefer to lie uphill and to

allow any liquids (urine, milk, rainwater, etc.) entering the stall to drain away from the stall bed and

to the manure alley. Sand stall are often filled fuller in the front than in the back to provide this

upward slope. If stalls ever become lower in the front that the back they will cause problems for the

cow attempting to rise. Field observation suggests that excessive slope can cause cows to lie with

their feet protruding into the manure alley.

Freestall Design – Cow Space Needs

Figure 1 shows the motion of a cow rising or reclining. It shows the three areas that must be

provided within the freestall: body space, head space and lunge space. Different authors have

suggested the proper length of each of these based on their work. Obviously these values vary with

the size of the animal.

Figure 1: Space envelop for rising and resting cow.

Cow Weight:

1200 lb

1450 lb

1650 lb

Body Space

62-64”

66-68”

70-72”

Head Space

17”

18”

19”

Lunge Space

14”

15”

16”

Total Stall Length-Open Stall Front

6.7 to 7.2‟

7 to 7.5‟

7.5 to 8.2‟

Total Stall Length -Closed Stall Front

7.7 to 8.2‟

8 to 8.5‟

8.5 to 9‟

Open Stall Front – cows can lunge through the stall front

Closed Stall Front – cows can not lunge through the stall front

Table 2: Suggested freestall dimensions for various size cows (McFarland 2003)

Cow Weight:

1400 lb

1600 lb

1800 lb

Body Space

68-70”

70-72”

72”

Total Space-Open Stall Front

8.5‟

9‟

Total Space-Closed Stall Front

9‟

10‟

Table 3: Suggested freestall dimensions for various size cows (Cook 2004)

Tables 2 and 3 above show some of the variation in current recommendations. Both show the need

for stall length to increase as animal size increases, but assume different weights. It is commonly

accepted that the average Holstein cow in the U.S is larger than a decade ago, and lends credibility

to increasing stall sizes. Genetics, nutrition and the use of custom heifer raising possibly have

caused this increase in size. When making a decision on stall size you should know the relative size

of your cows and how you plan to house them. Making the stall size the same for all pens of a new

facility allows the manager flexibility on how to use the pens, but complicates the decision on what

size stall to build. Building all stalls to meet the needs of your largest cows will result in smaller

cows using the stalls incorrectly, but making stalls too small for large cows will make them

uncomfortable.

Freestall – Length of Stall to Brisket Locator

Brisket locators, previously know as brisket boards, are placed in the stall to position the cow when

she lies down. The base of the brisket locator is normally placed 66-72” from the manure curb and

defines the amount of space a cow has for her body space. Experience has shown that 66” stall beds

and high brisket boards have not provided enough space for large cows and they lie with their rump

extended past the manure curb and sometimes even have their udders straddled across the edge of

the manure curb. Originally these locators were made of wood placed at an angle to accommodate

the shape of the animal as she rested the front of her body against them. Often the space in front of

the brisket board was filled with concrete to prevent a build-up of bedding materials. Less rigid

materials, which allow some flexibility as cows move, are now being used in place of boards and

have resulted in the use of this new term. Anderson observed animal behavior and suggested that

proper stall should allow cows to stretch their feet forward when lying down and have the ability to

extend their feet into the space in front of the brisket locator when rising. He observed that a cow

usually swings her foot high enough to clear a 4” obstacle and suggested this be the maximum

height of a brisket locator above a mattress or sand bedding. He discouraged the use of brackets to

support the brisket locators from the lower pipe of the stall divider because it obstructed the

extension of the cow‟s foot. In addition he suggested a 5” space should be provided between the top

of the brisket locator and the bottom of the stall divider to prevent leg entrapment of the animal.

This recommendation is easy to implement with mattress stalls since the brisket locator can be

attached to the stall surface, but becomes a challenge with sand based stalls that often do not have a

base to attach them. These recommendations lead to the new recommendation relating to stall

design in that the surface in front of the brisket locator should not be elevated above the stall surface

to allow the cow space for her feet.

Freestall Design – Total Stall Length

As mentioned earlier total stall length should provide body space, head space and lung space.

Tables 2 and 3 reflect different author‟s view of this need based on differences in cow sizes they

reference. Open front stalls allow a cow to extend past the stall perimeter when rising either by

placing their head in an adjacent stall in a head-to-head arrangement or with extra space provided in

front of the stall for single rows of stalls. Closed front stalls have some type of barrier that prevents

the cow from lunging outside the perimeter of the stall. If stalls are too short to allow cows to lunge

forward, a stall divider that allows the cow to the side should be selected. Cows normally prefer to

lunge forward and if allowed to do so often will lie straighter in their stall. Cows that are forced or

prefer to lunge to the side often lie at an angle in the stall which results in more manuring in the stall

and the increased problems associated with it. Anderson, 2003, reported that at a study farm with

16‟, open front, head-to-head freestalls, cows lunged diagonally 34% of the time when the facing

stall was empty and 81% of the time when the stall was occupied. At another farm, cows lunged

diagonally 68% of the time with the original 8‟ closed front stalls and 44% of the time with

modified stalls that had open fronts and loops with 38‟ wide side openings. This information

supports the decision to build closed front stalls longer than 8‟ and the choice of a stall divider

which allows diagonal lunging in case a cow is concerned with lunging into an occupied stall.

Freestall Design – Neck Rail Placement

Neck rails are placed in the front of the freestall (Figures 2 and 3) to position the animal when she

enters the stall. These normally are placed directly above the base of the brisket locator which

provides sufficient space for the animal to stand in with all four feet in the stall and positions the

cow so she defecates in the manure alley. For higher neck rails the neck rail should be moved back

toward the manure curb about 2” to reflect the shape of the cow. Cook‟s current recommendation

for sand based stalls is to shorten this distance by the width of the manure curb, forcing cows to

perch rather than stand with all four feet in the stall. This recommendations is based on observation

that cows normally will not stand on the manure curb, which encourages the cow to place her hind

legs inside or outside of the manure curb. Having cows stand with all four feet in the stall and the

back feet inside the manure curb leads to increased manuring in the stall, dirtier stalls, and increased

labor to maintain the stalls. Neck rail mountings should allow them to be moved forward or

backward as experience shows the stall bed is too short or too long, based on an excessive animal

perching or frequent manuring in the stall.

Recommendations for neck rail height above the stall surface changed the most in recent years.

Placement of the neck rail too low makes it difficult for animals to rise without hitting the rail and

discourages stall use. Previous recommendations specified a minimum distance between the stall

surface and the bottom of the neck rail to be 42”. Current recommendations are for neck rails be

mounted 48-50” above the stall base surface. Proper placement of neck rails is easier in mattress

based stalls since they have a constant surface level and the neck rail height is defined as the

distance above the stall surface, whereas surface elevation in sand stalls depends on the amount of

sand in the stall at any one time, so neck rail height is measured from the top of the manure curb.

Recent work by Fulwider and Palmer (2004) has shown that the percentage of time cows lie in a

stall increased significantly when the neck rail was raised from 45” to 50” in a mattress based

freestall barn (Table 4). A fifty cow pen had half of the stalls modified and the other half left

unchanged. Stall usage was recorded, before the stall changes and a 5-week acclimation period was

allowed before stall usage was again measured. There was no significant change in stall usage for

the existing stalls, but a significant increase in the percentage of stalls with a cow lying in the

modified stalls was observed (40.0 to 51.4%). This research was done in a 4-row, tail-to-tail barn,

with 46” wide and 8‟ long stalls, which indicates stall usage can be increase by changing neck rail

height, etc. without changing stall width or length. To increase the neck rail height new stall

divider types were installed and the stall divider mounting rails in the front of the stalls were

removed. Field experience has shown that removing horizontal mounting pipes (chin clippers) often

will increase stall usage because cows dislike hitting these rails as they attempt to rise. The increase

in stall use was significant and demonstrates the importance of proper stall design, but does not

prove the neck rail height alone caused the increase.

Before Neck Rail

Change

1-29 to 2-26-03

After Neck Rail

Change

4-03 to 5-01-03

Average Stocking Density

96%

94%

45” Neck rail before and after -

Percent of stalls with cows lying

42.1

43.8

45” Neck rail before , 50” after -

Percent of stalls with cows lying

40.0

51.4

a,b

Percentages with different superscripts differ (P < .05).

Table 4: Effect of neck rail height on the percentage of freestalls with cows lying in them.

Freestall Design – Stall Width

Stalls should be wide enough to allow animals to recline and rise easily. If stalls are too wide,

animals will tend to stand and lie at an angle in the stall. Smaller cows often will lie backward in the

stall which causes manure to be deposited in the front of the stall. Both of these situations can lead

to dirty cows and additional labor to clean stalls because animals will deposit manure on the stall

surface. For the average mature Holstein herd, 46-48” wide stalls often meet these requirements the

best. Larger stalls, 48-50” wide, may be considered for extremely large or pregnant dry cows. Often

48” stalls are built as a convenience to the builder, whereas, 46” stalls would offer the advantages

mentioned, plus allow more stalls per barn.

Cows prefer to lunge forward when rising, because transferring their weight forward allows them to

lift their hindquarters more easily. Eight feet of effective stall length has been recommended for

mature Holstein cows. Since the average size of cows has increase using 8‟ open front stalls or 9‟

closed front stalls seems to be adequate. Some people are advocating stalls longer than these

dimensions to provide a situation where cows have complete freedom to lunge forward. Anderson‟s

recommendations based on work with large Canadian Holsteins are often the basis for these

recommendations.

Tucker et al., 2004, reported the effect of cow lying and standing behavior and milk production

(Table 5). In this research 42”, 46” and 50” wide stalls were compared. The number of lying events

in 24 hours, the duration of lying bouts, total lying times, and milk production were compared. For

all these factors there was a significant advantage of the 46” stall over the 42” stall, but no

advantage of the 50” over the 46” stall. Increasing stall width decreased the amount of time cows

were half in and half out of stalls and increased the amount of time they stood with all four feet in

the stall. Based on this work the value of going to 50” stalls may be challenged. Observation also

suggests that if stalls are too wide cows tend to stand at and angle in the stall which results in

increased manuring in the stall and it‟s associated problems.

Stall width:

42” Stall

46” Stall

50” Stall

Lying events (number per24 h)

12.3

11.9

Duration of lying events (h per bout)

1.1

1.2

Total lying time (hrs per 24 h)

12.3

13.0

Perching (min per 24 hr)

Standing four feet in stall (min per 24 h)

Total time standing in stall (min per 24 h)

138

116

126

Milk production (lb per 24 hr)

103

101

102

Table 5. Lying and standing behavior and milk production for three stall widths (n=27)

Freestall Divider Design

There are many different freestall stall divider designs currently being marketed, and they are often

referred to by names such as side-lunge, wide loop, straight loop, etc. Whichever stall divider type

is selected, its length should allow 14” space between the end of the divider and the manure curb

once the stall dividers are mounted (Bickert et al., 2000). Allowing additional space encourages

cows to walk along the backs of the stalls and/or to enter another cow‟s space. Allowing less space

may result in cows hurting themselves as they enter the stall hitting the divider. In practice 12-14”

appear to work very well to eliminated these problems. Remember, barns having different stall

lengths, should have different length stall dividers.

Another important dimension is the distance from the top of the stall divider‟s bottom rail to the

stall base surface. If the stall divider provides sufficient space for the animal‟s head, then the bottom

rail needs to be high enough to discourage the animal from crawling over it. Field observation

suggests this bottom rail should be at least 12” above the stall surface. In the past producers have

reported dissatisfaction with extremely wide loop designs because cows got jammed in them and

they tended to encourage cows to lie at an angle in their stall. This was probably caused by the

divider being mounted too low which allowed the cow to craw over the lower divider bar. Current

stall design recommendations with their higher neck rail placement and the associated raising of the

lower rail of the divider appears to have solved this problems. A second consideration with divider

is the amount of space provided at the rear of the stall below results in cows lying at an angle in the

stall. Choosing a divider which has it‟s lower rail extend straight past the brisket locator 12‟-24‟

before rising to provide space for the cows hook bones will minimize this problem.

Barns with rows of head-to-head stalls allow animals to lunge into the stall in front of them. This

feature saves space, but can also lead to animals exiting through the front of the stall or being

jammed between neck rails as they stand and try to walk through. This is especially true of he newer

designs with higher neck rail placements. To discourage this a deterrent (strap, cable or pipe) may

be placed between the rows of stalls. Such a pipe must be high enough to allow the cow to lunge

forward unobstructed, but low enough to prevent her from exiting through the adjacent stall.

Current recommendations specify this deterrent to be placed 40” above the stall base surface on 8‟

stalls and 34‟ for 9‟ stalls.

Mattress Based Freestall Design

Figure 2 is an example of a mattress based freestall for average sized Holstein cows. Notice how

dimensions vary depending on the type of animal (First Lactation, Milking Cows (Lactation > 1),

and Dry Cows). These are only guidelines, but consider the fact that freestalls that are too large

cost extra money to build, result in dirty cows, and/or extra labor to keep stalls clean. Stalls that are

too small lead to increase injuries and culling rates and the potential for loss of milk production

because cows do not use the stalls as much as otherwise would be possible.

A B C

68" 70"

W idt h

48"

70" 72" 50"

46"

46" - 48"

48"

1300 lb .

1500 lb .

1600 lb .

St a ll L e n g t h

W eight

Example Mat t ress Based Freestall Design

f or Average Sized Holstein Cow

Alle y

M at t r r ess

8' f or open f r ont st all

9' f or c los ed f r o n t s t all

10" - 12"

Cur b

Po s t

Fir s t Lac t at ion Cow

M ilk ing Cow

Dr y Cow

Plum b L ine of Cur b Edge

Ea r t h

12" - 14"

10" - 12"

m e a s ur ed f r om

m a t t r es s s ur f ac e

40" f or open f r o n t s t all

Det e r r ent

Top of br is k et

lo c at or 4 " a b o v e

m at t r es s s ur f a c e

Av er age Hols t ein

2- 3% s lope down

t o r ear of s t a ll

Nec k Rail

Figure 2: Example of a mattress based freestall for average sized Holstein cows.

Sand Based Freestall Design

Figure 3 is an example of a sand freestall for average sized Holstein cows. Notice how dimensions

vary depending on the type of animal (First Lactation, Milking Cows (Lactation > 1), and Dry

Cows). These are only guidelines, but consider the fact that freestalls that are too large cost extra

money to build, result in dirty cows, and/or extra labor to keep stalls clean. Stalls that are too small

lead to increase injuries and culling rates and the potential for loss of milk production because cows

do not use the stalls as much as otherwise would be possible.

St a ll L e n g t h

8" - 10"

Alley

Cur b

A B C

68" 70"

W idt h

48"

70" 72" 50"

46"

46" - 48"

48"

1300 lb .

1500 lb .

1600 lb .

Example Sand Based Freestall Design

f or Average Sized Holst ein Cow

W eight

8' f or open f r ont s t a ll

9' f or c los ed f r ont s t all

Po s t

11" - 12"

Plum b L ine of Cu r b Edge

Fir s t L a c t at ion Cow

M ilk ing Cow

Dr y Cow

Dee p Bed of

Sa n d ( > 6" )

Nec k Rail

Det e r r e n t

40" f or open f r o n t s t all

12" - 14"

High s a n d lev el

Av er age Hols t ein

Low s a n d lev el

( t op of r e a r cur b)

2- 3% s lope down

t o r ear o f s t a ll

Ea r t h

m e a s ur ed f r om

t op of c ur b

Figure 3: Example of a sand based freestall for average sized Holstein cows.

Bedding Material Choices

Freestalls are often thought of as having two components, a stall base constructed of clay, concrete,

wood or some other material and a bedding surface. With deep sand freestalls, sand supports both

functions. Whatever components are selected, freestalls should conform to the shape of the cow

when she is resting, provide cushion when she is reclining and traction when she is rising. It is

recommended that the stall surface be 2-3% higher in the front than in the back of the stall. This

discourages forward movement while resting and improves stall drainage. Many people feel cows

actually prefer to lie up hill. One situation to avoid is stalls that are lower in the front than the back.

Cows have difficulty getting up under these circumstances. Excessive stall slope may also cause

cows to lie incorrectly.

Many different freestall combinations have been tried over the years with different costs and results.

Cows dislike concrete-based stalls unless a thick bedding surface is maintained on top of them.

Straw, sawdust, manure solids, and other organic bedding surface materials have been used

successfully over concrete bases, but their cost is sometimes prohibitive. Wood-based stalls have

not been successful because wood rots and gets slippery when wet. Clay-based stalls can provide

cow comfort but require a large maintenance effort since cows dig large holes in the stalls.

Producers have used rubber tires in freestall bases. Cows seem to like tires in stalls, and bedding

requirements are decreased, but getting the tires installed properly is very important. Tires should be

of the same size, placed tight together and carefully packed with material to hold them in place.

Tires can make it difficult to remove soiled bedding. Different types of rubber mats have been tried

over the years with mixed results. Some get slippery and promote hock damage, and others have

deteriorated in a short period of time.

Mattress-based stalls currently are very popular, and for most producers the choice of freestall bases

is between sand and mattresses. Mattress-based stalls normally have some rubber particles, water,

or other type of filler that conforms to the animal‟s body and may offer an insulating effect during

cold weather. They have a cover that provides animal traction, may be waterproof, and is durable

enough to withstand animal traffic. The initial cost of mattress-based stalls is normally $50-

100/stall, and their expected useful life is between 4 and 7 years. Mattress-based stalls need to have

some type of absorbent bedding applied to them, but the amount is less than deep-bedded stalls over

concrete. The initial investment in sand-based stalls is low, but the labor to fill and maintain them,

the cost of the sand used, and the adverse effects the sand has on manure handling and storage

results in a high maintenance cost.

Sand versus Mattresses - Performance and Producer Satisfaction

A survey of Wisconsin producers who increased herd size by at least 40% from 1994 to 1998 (Table

6) showed no significant difference in DHI milk production or somatic cell counts between those

using sand and those using mattresses after their expansion (Palmer and Bewley, 2000). Producers

using sand seemed to be more satisfied with cow comfort, and less satisfied with manure

management and bedding than those using mattresses. Sand users reported significantly higher

satisfaction scores for cow cleanliness and hock injury, whereas mattress users reported

significantly higher satisfaction with bedding use and cost and manure management. Culling rates,

although not significantly different, showed a slight numeric advantage to sand users.

Freestall Bedding Type

Mattresses

Sand

Number Herds

145

DHI 1998 RHA Milk(lbs)

22,519

22,539

Avg. Linear SCC

2.88

2.80

Culling Rate (%)

Cow Cleanliness*

4.12

4.47

Hock Damage*

4.22

4.72

Bedding Use and Cost*

4.25

3.95

Manure Management*

4.32

3.43

* Average satisfaction reported on a scale of 1 (very dissatisfied) to 5 (very satisfied)

Table 6 Average production and producer satisfaction values of herds using mattresses or sand

bedding.

An Iowa study, which was designed to evaluate six different freestall surfaces, found that stalls

ranked differently by week of trial, with cow preference switching between sand and mattresses

(Thoreson,2000). Sand ranked highest in the summer, but usage declined from summer to winter.

Other research conducted in Europe demonstrated that cows showed definite preference for some

types of mattresses and that cow preferences changed over time (Sonck and Daelemans, 1999). It

was suggested that cows need time to adjust to some types of mattresses and other mattresses get

harder and less comfortable over time.

Table 7 (Palmer, 2003) shows that stall base type affects cow preference. This study reported the

stall usage for a 4-row freestall barn with 100% stocking rate. Observations of cows lying or

occupying stalls (standing or lying) were recorded for a nine month period. Sand and mattress-I

(Rubber filled) based stalls consistently had larger stall use percentages; concrete and soft rubber

mats consistently the lowest percentages; and mattress-II (Foam filled) and waterbeds percentages

were intermediate. The sand based stalls had the highest overall lying percentage, but mattress-I and

mattress-II had the highest stall occupied percentages. Cows appear to prefer to stand on soft

surfaces provided by mattresses or soft rubber mats to sand stalls or concrete alleys. The lying

percentage advantage of sand over mattress-type-I (68.7% > 65.2%) was small compared to the stall

occupied advantage of mattress-type-I over sand (88.3% > 79.0%). This suggests cows like to lie

down on both stall bases, but prefer to spend non-lying time standing in mattress-type-I based stalls

rather than on concrete manure alleys. Some stall base types were consistently inferior to others.

Lying percentages for concrete and soft rubber mats were always below the average lying

percentages. Mattress-I based stalls consistently ranked higher than mattress-II for lying and stall

occupied percentages, which indicates not all mattresses are equally desirable to cows and making

general statements about “mattresses” may be misleading. The length of time cows are exposed to

the different stall bases affects lying and occupied percentages. The waterbed based stalls required

a longer adaptation time whereas use of soft rubber mat based stalls in this trial decreased over time.

Soft

Rubber

Mat

Type I

Waterbed

Mattress-I

(Rubber

Filled)

Mattress-II

(Foam

Filled)

Concrete

Sand

Average

% Lying

32.9

45.4

65.2

57.4

22.8

68.7

51.0

% Standing

24.6

7.9

17.0

20.7

8.8

3.3

12.1

% Occupied

64.8

61.6

88.3

84.1

38.7

79.0

70.1

No. Obs.

6727

7688

13454

Table 7. Cow Preference for different stall base types “Experiment 1” for 4-row barn with 100%

stocking density.

Cook et al., 2004, studied the differences in behavior of nonlame cows, slightly lame cows,

and

moderately lame cows in 6 free stall barns with sand bedding

(SAND) vs. 6 free stall barns with

rubber-crumb geotextile mattress

surfaces (MAT) were documented in Wisconsin dairy herds. All

lactating cows in the 12 herds were observed and given a locomotion

score based on a 4-point scale:

1 = nonlame, 2 = slightly lame,

3 = moderately lame, and 4 = severely lame. Herd least square

means ±SE for prevalence of clinical lameness (locomotion

scores = 3 and 4) were 11.1 vs. 24.0 ±

1.7% for herds

using SAND vs. MAT surfaces, respectively (Table 8). Herd size, stocking density,

rolling herd average milk yield, annual turnover rate and mean ambient temperature on visit day

were not statistically different for there MAT or SAND herds. Culling rate although not statistically

different showed a numeric advantage for SAND herds (36.5 vs 28.8) which is consistent with the

results reported by Bewley et al. 2003. The major finding was that the average herd prevalence of

clinical mastitis was significantly higher in MAT herds than SAND herds (24.0 vs 11.1), where

clinical lameness was defined as cows having a locomotion score of 3 or 4.

MAT

SAND

Herd size (no. cows)

304.7

297.7

30.2

0.87

Cows in pen (no.)

77.3

95.8

7.8

0.12

Stocking rate (high pen %)

107.8

108.0

5.0

0.98

Rolling herd average milk yield (kg)

11,241

11,912

547.5

0.41

Annual turnover rate (%)

36.5

28.8

2.9

0.09

Mean ambient visit temperature (°C)

7.2

8.3

0.4

0.73

Herd prevalence of clinical lameness

(% all milking

cows)

24.0

11.1

1.7

<0.001

Clinical lameness includes cows that had locomotion scores of 3 and 4 and were either

moderately or severely lame. Locomotion score scale: 1 = nonlame, 2 = slightly lame, 3 =

moderately lame, 4 = severely lame.

Table 8. Least square means and SE of herd level background data for 6 herds using mattresses

(MAT) and 6 herds using sand bedding (SAND).

Subsets of 10 cows

per herd with locomotion scores of 1 to 3 were observed via

video cameras for

24-h periods (Table 9). There was no difference is the lying time between MAT and SAND barns

(11.66 vs 12.01), and cows in MAT herds spent more

time standing in free stalls per day than cows

in SAND herds (3.44 vs 1.83) which agrees with the findings of Fulwider and Palmer, 2003. Cows

in SAND barns were also found to spend more time feeding than MAT barns (4.65 vs 4.08) and had

a higher number of stall use sessions (7.57 vs 6.92). The proportion of lying bouts greater than 60

minutes was higher for SAND herds than MAT herds (0.61 vs 0.49).

Daily activity

MAT

SAND

Time lying in stall

11.66

12.01

0.56

Time standing in stall

3.44

1.83

0.002

Time up in alley

2.27

2.34

0.66

Time up feeding

4.08

4.65

0.03

Time up milking

2.58

3.21

0.37

Number of stall use sessions

6.92

7.57

0.03

Proportion of lying bouts >60 minutes

.49

.61

0.03

Table 9. Mean daily activity patterns (h/d) for 60 cows in 6 herds using mattresses (MAT) and for

60 cows in 6 herds using sand bedding (SAND).

Figure 4 shows how daily activity patterns of cows vary by locomotion

score between MAT and

SAND herds. Activity patterns are consistent

in cows in SAND herds across all locomotion scores

with little

variation. Nonlame cows in MAT herds behave similar to all cows

in SAND herds, apart

from a small but significantly higher time

up in stall. In contrast, cows in MAT herds that are

slightly

lame and moderately lame show the modifications in behavior. Differences in standing

times were 0.73 h/d for cows that were

not lame, 2.32 h/d for cows that were slightly lame, and 4.31

h/d for cows that were moderately lame in MAT herds compared

with equivalent cows in SAND

herds. In MAT herds, the increase

in time spent standing in the stall in moderately lame cows

was

associated with a significant reduction in stall use sessions

per day, which impacted daily lying

time. As time standing up in stall

increases, time spent performing other activities is reduced.

Time

up milking is largely unchanged, but time up in alley is

significantly reduced (P <0.05). Moderately

lame cows in

MAT herds had significantly (P = 0.003) fewer mean number of stall use sessions at

0.62 compared with moderately lame cows

in SAND herds at 8.50.

Figure 4. Daily time budgets for time lying down in stall (TDIS), time standing up in stall (TUIS),

time up in alley (TUIA), time up feeding (TUF), and time up milking (TUM) in 73 nonlame

(locomotion score = 1), 37 slightly lame (locomotion score = 2), and 10 moderately lame

(locomotion score = 3) cows in 6 MAT (rubber crumb-filled geo-textile mattress free stall) and 6

SAND (sand-bedded free stall) herds.

Table 10 shows the results of a second experiment conducted in the same barn as Experiment 1

(Fullwider and Palmer, 2003). Two different mattress types and three different soft rubber mat types

replaced the sand, concrete and waterbed stall bases. Cow preference was strongest for foam and

rubber filled mattresses. Cow preference for the two mattress types previously tested and which

had been preferred now was intermediate. These two mattress types were installed approximately

three years before the other stall bases, so it is not possible to determine if the new mattress types

were superior or if the decrease in cow preference of the existing two types was due to an aging

effect. Rubber mats were consistently used the least. Differences in stall use existed between

different manufacturers‟ foam and rubber filled mattresses. Visual inspection shows differences in

deterioration and surface levelness of the different products over time. These factors can influence

the life expectancy of each product and should be considered along with cow preference when

making a buying decision.

Freestall Maintenance

One key point that must be emphasized is that no matter what stall type is selected, maintenance of

the stalls is critical. Mattress stalls should be bedded frequently, preferable daily, to insure there is a

layer of bedding on the stall surface at all times. Sand stalls should be filled frequently to maintain a

sand level even with the top of the manure curb at the back at all times. This usually requires the

sand stall surface in the front of the stall to be approximately 5 inches higher immediately after

filling and no lower than the level of the manure curb when refilling is needed. Sand stalls should be

leveled at least once per day. Any manure deposited in the stall should be removed every milking

no matter what type of stall base is selected.

Stall Base

Exp 2

% Lying

6-19/12-17

Exp 1

% Lying

(Ranking)

Exp 2

% Occupied

6-19/12-17

Exp 1

% Lying

(Ranking)

Mattress-Type III

(Foam Filled)

62 %

91 %

Mattress Type IV

(Rubber Filled)

59 %

84 %

Mattress Type I*

(Rubber Filled)

57 %

65 % (1)

85 %

88 % (1)

Mattress Type II*

(Foam Filled)

52 %

57 % (2)

81 %

84 % (2)

Soft Rubber Mat

Type II

51 %

73 %

Soft Rubber Mat

Type III

43 %

64 %

Soft Rubber Mat

Type IV

42 %

65 %

Average

52 %

51 %

78 %

70 %

a,b,c,d

Percentages within rows, lying & occupied analyzed separately, different superscripts

significantly differ (P < .05).

Table 10: Cow Preference for different stall base types “Experiment 2” for 4-row barn with 100%

stocking density.

Use of Rubber Alley Mats

Previous work by Fulwider and Palmer, 2003, indicated that cows lie down as much time in well

designed mattress stalls as in sand stalls, but spend more time standing in mattresses based stalls.

Cook et al., 2004a found the same to be true (Table 9). Different reasons have been proposed to

explain these phenomena. In the fall of 2003 rubber alley mats (RAM) were installed over all alleys

in the same pen as stall preference studies had been conducted earlier. Table 11 shows the effect of

rubber alley mats on stall use (Fulwider and Palmer, 2003). Stall use was recorded for 31 days

before the RAM‟s were installed. A three week acclimation period was given to allow cows to

adjust their behavior patterns and then stall activities were recorded and the results compared to the

before vales. No change in the amount of stalls with a cow lying in them was found, but the percent

of stalls with cows standing in them decreased significantly. This was interpreted as cows preferring

to stand on soft surfaces. In other words, cows preferred to strand in soft stalls when hard concrete

floors were the alternative.

Before RAM‟s

8-10 to 9-11-03

(97% Stocking Density)

After RAM‟s

10-1 to 10-23-03

(92% Stocking Density)

% of Stalls with Cows Lying

% of Stalls with Cows Standing

a, b

Means within rows with the same letter are not significantly different (P<.05)

Table 11: Effect of rubber alley mats (RAM) on stall use.

Alleys

Alleys are used by the animals to move freely within the barn to access stalls, water, and feed and to

seek comfortable areas of the barn. Alleys are used by operators to collect manure and move

animals around within the system. Alleys must be designed for comfortable movement of animals,

safety and convenience of operators, and access by equipment. To be comfortable for cows, alleys

must have slip-resistant surfaces and enough width to provide ease of movement and personal

space. Cows need to be able to back out of freestalls while other cows are standing at the bunk to

eat. Cows need to be able to walk behind cows standing at the bunk to eat and to walk behind those

standing at a waterer. The values in Table 12 are minimums which allow for these easy

movements. Use the recommended values for maximum cow comfort. When cows are being

herded (to parlor), alleys must be wide enough to keep the group moving at a reasonable pace.

Alleys must be wide enough so one or two cows stopping does not halt the group. When animals

must be herded, use the values in Table 13 to select the alley width. Alleys where animals are

herded include those within the housing unit, including the crossover at the end of the stall rows and

the travel lane to the parlor. Initial cost can be reduced by making lanes/alleys narrower, but

increased labor cost for herding slow-moving cows will result in a much higher annual cost than

would the annualized cost of the initial investment. Cow comfort issues will pay additional

dividends.

Alley Location

Alley Width (ft)

Minimum

Recommended*

Stalls across from feed manger

Alley between tail-to-tail stalls

Feed manger with no stalls on other side of alley

Alley serving one row of stalls

+++

Crossover with waterer (measured from cow side

of waterer)

* Wider alleys will provide more comfort. Consider a wider alley if equipment must use the

alley for manure scraping (tractor, industrial loader, etc.)

McFarland, 2003

Bickert, et al., 2000.

+++

Graves, 1995

Table 12. Alley widths which allow convenient animal movements

Group Size

Min. Alley Width (ft)

Less than 150 cows

12-16

More than 150 cows

McFarland, 2003

Table 13. Minimum alley width for herded cows

Floor Surfaces

Cows must feel comfortable if they are to behave in a natural manner. Good footing is essential to

natural walking behavior and to encourage cows to move about the barn and express heat freely.

Firm soil, free of stones and mud, is probably the best walking surface for cows, but it is impractical

as a walking surface for cows in confinement. Concrete is the traditional surface of choice, but

some producers are considering other materials including rubber. Concrete has the advantage of

durability but the disadvantage of being hard with no cushioning. Concrete must remain slip-

resistant throughout its life yet not be so abrasive that it causes hoof damage. Slip resistance can be

provided by: broom finishing, grooving (bull float or cutting), applying aggregates and epoxy

coatings, and surface roughening (scabbling). Even sand bedding deposited in the alleys improves

traction. Care must be taken to avoid excessive roughness that will wear hooves rapidly. Grooving

or broom finishing "green" concrete can leave abrasive surfaces. Plan to drag concrete slabs or use

a steel blade with down pressure to smooth these surfaces before allowing cows to use them.

Continued scraping with a steel blade over several years will polish concrete, making it more

slippery. When this occurs, use a surface treatment to improve traction. See the article by Gooch

(2003a) and MWPS-7 for recommendations on preparing slip-resistant floors.

Crossover Alleys

Crossover alleys allow animals to move from feeding alley to freestall alley. To allow

convenient access, crossover alleys should be spaced at 60- to 80-ft intervals within the freestall

row (McFarland, 2003). Crossover alleys are a convenient place to locate waterers, however

animals using waterers can interfere with cows that want to crossover. Use the values in Table X to

assure adequate width for animal movement. The curb at the rear of the freestall keeps scraped

manure from flowing into the stall. Crossovers past which manure is scraped should have a similar

step up to a platform. The preferred step up height is 6 inches with no more than 8 inches

(McFarland, 2003). Crown the crossover with a maximum slope of 2 to 4% to drain manure, urine

and spilled water (Graves, 1995). The step of a crossover can slow animals being herded. If the

crossover where cows are herded is at the end of the barn where manure is not accumulating in front

of the scraper, consider using no step there. The lack of a step can facilitate the scraping equipment

moving between alleys without having to go outside the barn.

Watering

Water is a critical ingredient for producing milk. Cows prefer to drink soon after being milked and

during feeding bouts. Producers have observed many cows consuming water when it is provided in

lanes used to return from the parlor. Their next stop is usually the feed bunk. Locate waterers in

return lanes near the parlor and give cows access to waterers in the housing area closest to the

parlor. Since dominant cows can force timid cows away from water, use at least two watering

locations within a pen. In larger groups, more than two watering locations can be beneficial to

reduce distance between waterers. Consider installing seasonal watering locations to give cows

access to water during heat stress periods. Locate waterers away from feed mangers to reduce the

amount of feed entering the waterer. A cow requires about 2 feet of waterer length to stand and

drink at a trough. Using 1.5 inches of waterer length per cow in a group, each watering space will

service 16 cows. An example for sizing the length of waterers needed for a group of 80 cows with

three watering locations might look like:

Total water trough length (minumum) = 80 cows  1.5 in/cow  1 ft/12 in = 10 ft

Distributing that over three watering locations:

Waterer length = 10 ft  3 locations = 3.3 ft/location

So waterers longer than 3.3 ft would satisfy the requirement in the housing pen. Waterers in the

parlor return should be the number of cows per side times 2 ft/cow.

Cows want clean, odor-free water. Waterers should be set up to be easily and frequently cleaned.

Using shallow water depths (4 to 8 inches, McFarland, 2003) and 6- to 12-inch top edge to bottom

maximizes the amount of fresh water in the trough and minimizes the amount of water discharged at

each cleaning. For large frame cows, place waterers so the top edge is 24 inches (21 to 22 inches

for small frame cows) above the floor upon which the front hooves are standing.

Design the water delivery rate to meet the rate of drinking by all cows at the trough. Using a 5

gal/min consumption rate for a cow, the 4-ft troughs in the previous example will require 10 gal/min

delivery for two cows using the waterer. Locate a waterproof wall between waterers placed next to

freestalls to keep water from being splashed into the stall and to keep cows from reaching for water

while standing in the stall. Use a fence around the other three sides of waterers to keep cows from

placing their feet in the waterer. Locate the guard rail above the water edge and provide 24 inches

clear opening between waterer edge and rail.

Feed Mangers

Design feed mangers to allow cows easy access to high quality feed at all times. Roofs over feed

mangers protect the feed from sun and precipitation, each of which can reduce feed quality and

increase feed refusal. A roof over the cows protects them from sun, wind and precipitation which

can act as deterrents to approaching the feed bunk in certain seasons.

Feed mangers should be flat (no cupping, no front wall) to facilitate easy mechanical clean out and

drainage of precipitation. The manger feeding surface should be smooth, of low porosity, and long

lasting. A smooth surface will not abrade the cow's tongue. Porous surfaces absorb liquids

containing soluble organic compounds. These compounds produce odors upon decomposing. The

odors can repulse cows from eating on those surfaces. Suitable surfaces can be provided by

troweled high-strength concrete, glazed tile, plastic sheets, and epoxy coatings. It should be noted

that high-strength (4500 psi) concrete is not run of the mill concrete. It contains extra cement, less

water, and possibly admixtures. Standard concrete will erode quickly in a manger, exposing

aggregate and leaving a rough surface. Specify high-strength concrete for a low-cost, long-lasting

feed manger surface. A 3-ft wide eating surface provides adequate bunk capacity.

If the drive of a drive-by feed manger is gravel, the manger and the area beyond it should be hard-

surfaced to allow feed to be pushed up without pushing up gravel. Make the paved area 5 feet wide

as measured from the feed barrier curb (McFarland, 2003). Slope this paved area away from the

feed barrier curb at a rate of 1/8 inch per 1 foot to shed precipitation away from the feed.

The feed barrier prevents cows from exiting the pen into the feed manger. Other design criteria

include: keeps feed from entering the cow alley, allows cow easy access to feed, allows cow to eat

in a grazing-like posture, exerts minimal force on the cow as she reaches, and exposes the cow to

smooth (not sharp or abrasive) surfaces. These criteria can be met by using a curb height of no

more than 21 inches (1400-lb cows) above the floor upon which the cows' feet rest. The manger

surface should be 2 to 6 inches above that same floor. Mangers higher than this have reduced feed

storage capacity, reduce the amount of saliva produced by the cow (lowered digestive buffering),

and can contribute to feed throwing by the cows.

Feed barriers can include self-locking headgates for animal capture. Self-locks should be designed

to allow cows easy access to feed without having to rotate their heads. Look for self-locks which

permit quick and safe extraction of a downed cow. The bottom rail of the gang of self- locks should

be mounted no more than 21 inches above the floor upon which the cow stands. This will require

the curb to be shorter than 21 inches. Consult the stall manufacturer about recommended curb

height. Self-locking headgate panels are often installed at a slight angle with the top, tipped away

from the plane of the curb. Research has shown that cows put less force on the panel and

experience less slipping when reaching for feed with these tipped-away panels. Research at Kansas

State University (Brouk et. al. 2001) showed that Dry Matter Intake and Milk Production were not

affected by self-locking headgates for cows trained in their use vs a post and rail barrier.

Post and rail feed barriers do not allow animal capture but do provide clear and easy access to feed.

The rail is 48 inches above the cow alley floor and 8 to 12 inches in front of the curb as measured

from the cow side. The rail should be a smooth round pipe which exerts minimal force and abrasion

on the cow if she pushes against it. The location of the rail requires it be spaced away from the

support post. Cable is not an acceptable substitute for the rail as it concentrates forces on a small

portion of the neck and is abrasive to the hide, each of which cause injury and discomfort.

Bunk space recommendations are based on the management plan and cow behavior. Most cows

returning from the milking parlor will approach the bunk to eat before going to lie down. Bunk

space must be adequate for animals returning from the parlor to cycle through a trip to the bunk. A

more severe test of bunk length is the practice of allowing the bunk to be "cleaned up" for an hour

or more before new feed is delivered. Using this practice requires all animals to approach the bunk

at once. "Top dressing" with grain causes a similar response. Using self-locking headgates

effectively requires sufficient bunk length for all animals in the group to get to the bunk. Use the

values in Table 14 when designing bunk lengths based on management.

Management Practice

Min. Bunk Length/Cow

(in/cow)

All animals must access the bunk at one time (empty

bunk refilled, self locks used, top dress grain, etc.)

27*

Mixed ration always available

* If self-locks will be used, consult manufacturer for specific bunk length per lock-up.

Table 14. Minimum bunk length per cow based on management (Bickert, et al., 2000)

Thermal Comfort

High temperature has more impact on cow comfort than does low temperature. Cows are adapted to

cooler climates, eating more to compensate for low temperatures. Practices which minimize the

effects of cold stress include delivering extra feed, keeping cows dry (roofs, dry resting area), and

offering draft-free spaces (walls, windbreaks). Providing supplemental heat for cow housing is not

economical in Wisconsin. During high temperature and humidity conditions, cows reduce feed

intake, increase water consumption, seek shade, respire at a faster rate, and will lie in wet areas.

Milk production and reproduction efficiency decline as a result of heat stress. The economic impact

of heat stress warrants extra investments to reduce such impacts. Practices to alleviate heat stress

include: providing adequate quantity and quality of drinking water, providing shade, providing

ventilation (removes excess heat and moisture), increasing air velocity past the cow, sprinkling

cows to help dissipate heat and lower the air temperature (evaporative cooling, air conditioning),

and providing a soft place to lie down.

Ventilation

Ventilation is the process of exchanging contaminated in-the-barn air with good quality outside air.

Ventilation is needed continuously throughout the year. The required ventilation rate is lower in

winter and higher in summer. Ventilation can be accomplished by natural and mechanical methods.

Natural ventilation capitalizes on the forces of nature (thermal buoyancy, wind pressure), while

mechanical ventilation uses fans to cause the air exchange.

Natural Ventilation

For natural ventilation to work best, design criteria must maximize the use of the wind. These

design criteria include:

Ridge opening* 2 inches per 10 feet of building width

Eave opening (winter)* 1 inch per 10 feet of building width (both eaves)

Roof slope* 4 inches vertical for 12 inches horizontal

Min. sidewall clear

opening (ft);

both walls in summer Building width (ft)

9 < 70

11 70 to 95

13 > 95

Separation distance from Separation distance is a function of

obstructions located height and length of the obstruction.

downwind of naturally For solid walled buildings, a 100-ft separation

ventilated building is a bare minimum.

Terrain Locate at elevated site, avoid low

areas, bluffs, woods, etc.

* Bickert, et al., 2000.

Mechanical Ventilation

Use mechanical ventilation to cause an air exchange when natural ventilation cannot be used or

where ventilation and air velocity and/or air cooling are combined. A mechanical ventilation

system should be designed to exchange 50 cubic ft/min (cfm) per 1400-lb cow in winter, 170

cfm/cow in mild weather, and at least 470 cfm/cow in hot weather (Bickert, et al., 2000). The hot

weather ventilation rate may not provide enough air velocity to keep cows comfortable, but it

should limit building temperature rise to 1 to 3 degrees above outside. Mechanical ventilation can

be designed as negative pressure (fans blow out of barn) or positive pressure (fans blow into barn).

Common negative pressure systems are: fans in walls with slot or area inlets, and wind tunnel (fans

on one end and inlet at other end). Common positive pressure systems are: positive pressure wind

tunnels (fans blow in one end and air outlets at other end), ducted systems (fans force air into barn

though ducts), and distributed fan systems (fans located in walls or ceiling around the barn). A

combination of both negative and positive pressure systems may also be installed. Wind tunnel

systems combine ventilation and air velocity to help keep cows cooled. Effective wind tunnel

designs for freestall barns use an air velocity of 500 to 600 ft/min. This requires limiting the barn

cross-section through which air flows by means of using a ceiling or vertical baffles suspended in

the vaulted space above the eave at a maximum spacing of 50 feet (Gooch, 2003b). One limitation

of wind tunnels is the impact on air movement downstream of obstructions. Obstructions include:

waterers and walls behind them, stall curbs, stall dividers and fences, and, most importantly, the

cows themselves. Some producers will bleed air into the barn through narrow openings at the

bottom of the wall curtain to introduce fresh air with velocity to cows lying in stalls along the wall.

Cow Cooling

Cows benefit from moving air past their body surfaces at 3 to 6 mph of velocity. However, when

temperatures approach or exceed 100F, air velocity has limited effect. Sprinkling cows with water

to wet them to the hide allows their body heat to evaporate the water, providing surface cooling.

Combining the effect of sprinkling and high air velocity past the body surface maximizes the

cooling benefit. In winter this process is known as "wind chill". Researchers at Kansas State

University (Brouk et. al., 2003) have shown the benefits of reducing heat stress by reducing the

wetting cycle time. They currently recommend cycle controllers that reduce the sprinkling cycle

time as temperature increases (Table 15). Sprinkler nozzles are usually mounted to spray cows'

backs as they stand at the feed manger, in the holding area, and in the parlor return lane. See some

of the Recommended Readings for useful design information.

Temperature Range (F)

Soaking Frequency (min)

70-80

81-90

> 90

Table 15. Recommended soaking frequency based on ambient temperature

Circulating fans are located to blow air onto the cows standing in the feed alley, lying in freestalls,

and standing in the holding area and in the parlor. Circulating fans have the most effect when they

are spaced at no more than 30-ft intervals for 36-inch diameter fans and at less than or equal to 40-ft

intervals when they are greater than 48 inches in diameter. The fans should be aimed downward so

the projection of the fan axis impacts the floor directly under the next fan in a series. Circulating

fans have the most benefit when they blow air parallel to a cow's body length as in the holding area.

The effectiveness is reduced when upstream cows block the air flow as in the feed line and cow

stalls. Consider a system of fans that blows air parallel to a cow's body in freestall housing areas.

Locate 150- to 180-degree sprinkler nozzles over cows standing at the manger and 360-degree

nozzles in the holding area and return lanes. Space nozzles so the spray pattern overlaps to get good

coverage. A nozzle spacing of 6 to 8 feet can work well at the manger and in the holding area.

Select nozzles capable of delivering 0.03 gal/ft

and 0.3 gal/min at 10 psi of line pressure. Plan to

deliver 0.08 gal/cow to achieve adequate wetting. If a timer is used to reduce the on-off cycle time

to 5 minutes, the sprinklers must have the capacity to wet the cows in about one minute. This

requires the system to deliver 0.3 gal/min/sprinkler. High-capacity sprinkling systems require the

delivery system be sized adequately. Piping should be large enough to avoid high friction losses,

and water well delivery and pumping capacity should be large enough. For example, a 100-cow

group at the feed manger receiving 0.08 gal/cow/min requires a delivery rate of 8 gal/min. Most

nozzles allow the delivery line to drain down during off cycles. This drain down water enters the

manure and manure storage, increasing the cost of manure transport. Installing delivery lines

perfectly level and installing sprinklers on the top of the line or using valved nozzles on sloping

lines can conserve water and avoid having to handle a greater volume of manure. The extra cost of

these systems can pay for themselves quickly by reducing the cost of manure hauling and increased

manure storage capacity.

Evaporative Cooling

Warm, dry air can be cooled by using it to evaporate water. This principle is used with misting and

evaporative cooling pads. The air temperature decline is a function of air relative humidity and the

quantity of water added to that air. These systems can work best when the relative humidity

remains low throughout the day (Brouk et. al., 2003). In humid climates like Wisconsin, the

relative humidity drops during the day and increases at night. Thus an evaporative cooling system

works best only during the day. The effect of evaporative cooling may be limited by the rate at

which water can be evaporated into the air. Large evaporative pads and fine water droplet mists are

required to maximize water evaporation. Consult equipment manufacturers for proper system

designs.

Evaporative cooling technologies may allow for lower ventilation rates in summer due to reduced

heat stress. However, care must be taken to limit the maximum relative humidity in the barn.

Animals still need to evaporate water from their bodies to cool themselves. High humidity also

supports aerosol-borne pathogens which can increase disease incidence. High humidity makes it

more difficult to keep stall surfaces dry. Avoid misting over the stalls to avoid condensation and

spray precipitating onto the stall surfaces. Evaporative cooling pads can be conveniently

incorporated into wind tunnel ventilated freestall and tie stall barns.