A26—Lancaster Farming, Saturday, February 6,1982
BY DONNA TOMMELLEO
FRANCONIA It’s no secret
that Pennsylvania dairy farms are
diminishing in number but
growing larger in size.
The old bank barn that com
fortably housed the 30-head
milking string can turn into a
disease-laden environment if more
cattle have been added without
proper ventilation
To point out the bemfits of
adequate ventilation, Dan Meyer,
Penn State Extension agriculture
engineer, spoke before a group of
southeastern Pennsylvania dairy
fanners on Thursday in Mon
tgomery County.
"I don’t think you can get enough
air flow in a bam,’ ’ he stated.
In the past 18 months, Meyer has
visited more than 200 barns in the
state. The ag engineer explained
that in operations experiencing
problems, inadequate ventilation
was the cause about 80 percent of
the time.
With several brand name
systems on the market, Meyer
offered some advice when
choosing the correct system to fit
the farmer’s needs.
“Shop around, look for the best
deal and stay away from
automated systems,” Meyer
cautioned. Instead, he suggested
that farmers choose the system
that they could easily adjust and
repair if necessary.
Before purchasing a system,
Meyer stressed the importance of
understanding the basic principles
of ventilation.
An adequate system, either
mechanical or natural, should
provide oxygen, remove moisture
and odors, prevent heat buildup
and dilute air-contained disease
organisms. "
Respiratory diseases go hand-m
-hand with poor ventilation, said
Meyer. He cited the case of one
dairy farmer that had treated nine
cows for pneumonia before
changing his system.
The biggest difficulties occur in
barns where young stock are
housed with older animals. He
cautioned that young animals are
targets if circulating air passes
Dan syer, ri v tension ag engineer, advises
dairyman Jack Seasholtz on the plans for Seasholtz's new
pole barn. Meyer presented an all-day dairy ventilation
seminar in Montgomery Co. on Thursday.
Keep cow cool, comfortable and content
from the older animals to them.
Even outside, said Meyer, a far
mer has to be aware of exhaust fan
placements. An exhaust fan
blowing directly on a calf hutch,
not only dumps off organisms but
warm air as well. The warm air
condenses on the call causing
moisture which chills the young
animal.
If at all possible, said Meyer, the
best way to raise young animals is
to get them outside. But for those
farmers with limited space,
mechanical systems may be the
answer.
Meyer explained that a
mechanical system generally costs
more to install and operate daily,
then natural ventilation.
A mechanical system consists of
one or more fans, thermostats and
a senes of inlets. It is used where
control of room temperature and
air movement is a must.
The primary disadvantage ot
mechamcal ventilation are cost,
both initial and daily operating
costs. Also, supplemental heat
may be needed if the animals do
not produce enough body heat in
the winter, due to their heat being
lost through the ventilation
system.
“But you can’t afford not to have
it,” Meyer stressed.
The optimum temperature range
tor dairy cows is between 40 and 50
degrees Fahrenheit, said Meyer.
The combination of that tem
perature and a maximum relative
humidity of about 70 percent ac
counts tor barn-full of contented
creatures.
If constant room temperature is
to be maintained, the heat
produced by animals, sup
plemental space heaters and creep
heaters must equal the total heat
lost through the building' walls,
ceiling and floor and through the
ventilation system.
Relative timidity is the amount
of water vapor in the air compared
to the amount the air could carry if
saturated. Relative humidity is
important considerations in
confinement livestock housing for
various reasons.
y'k relative humidity of 50 to 80
dairy ventilation seminar
Mont
&'"f& : V- ' ..
“ * ,f H* W£
't&^d'rt
ik * *••" - -" •>’
“Calf hutches are the simplest form of
natural ventilation,” says Penn State Ex
tension agriculture engineer Dan Meyer.
percent is detrimental to the
airborn bacteria found in hvetock
buildings.
very high and very low
RH can lead to respiratory
ailments.
levels higher than 80
percent are conducive to survival
ot bacteria and spread of disease.
humidity also contributes
to a rapid deterioration of building
and equipment.
Waterers, teed, manure pits, wet
surfaces of floor, gutters and tree
stall alleys and water vapor from
the animals’ lungs and skin all
The VPI heifer barn design is icoming mo»
popular for Pennsylvania farmers, says Meyer.
The combination of the open front and the
contribute to moisture in the air.
Meyer reported that as much as
10 percent production increase in
the summer is possible with the
correct system. He said that many
farmers, with installed sytems,
have reported that conception
rate, which usually dips in the hot
humid weather, equalled that of
the winter months.
But for the farmer that has the
space to raise most young stock
outdoors, a natural ventilation
system may be the answer.
“Take advantage of all that free
air movement in the barn, ”
I '
f'
%/ — '
"This sure bests a bam full of swishing tails"
/■ *-
5 J *> s
✓* v £,
v&CT' * - r\
■tX* >■
vj* „ >v -
■ *'” n ' *“
»' V . , ~ '''
•%P ,/
1 _*
;• .•V'V?
T*- 1 * sjM>
* * X
continuous drop flaps in the back allows for a
continual air exchange.
Sj
£-* v < v ,< fls
' «#• „> * +2s
,—■ ' •
f * t” 4 '■*****■ V* "Sr
v-r
- <».„
- ✓ *9-*
•«?*>
,- ■ >" > I'C.v—F.**,,/-;
Calves have the option of staying inside during
inclement weather or basking in warm sun
shine on nice days.
*• v
*■ is
' ih
*
suggested Meyer.
Natural ventilation, however,
cannot adequately insure an en
vironmentally controlled at
mosphere, since inside tem
peratures and air exchange rate
fluctuate with outside changes in
temperatures and wind conditions.
Its use in confinement livestock
production, therefore, is limited to
large animal housing, usually
through sidewall openings.
"A calf hutch is the simplest
torm ot natural ventilation,” noted
Meyer.
(Turn to Page A 27)
I* ;X"*'
£ S'* <-<• it^s
** iv* /
„ S*£
'<***• ,v»- -A 5
Xv
" 5 - ’•
v *
- vC v
’^v
/* * <A
<*
v v
~i ' '"
' -