Temperatures and humidities outside and
inside freestall barns and cow respiration
rates were monitored on three Kansas and
two Nebraska commercial dairy farms during
the summer of 1999. All farms had 4-row
freestall buildings with different cooling
systems. The first Kansas barn could be
cooled naturally and mechanically using
evaporative cooling pads located on the east
and west walls. The second Kansas barn was
ventilated naturally by manually lowering the
sidewall curtains and without sprinkling or
ventilation systems. The third Kansas barn
was ventilated naturally and equipped with
fans located over the freestalls and feed-line
sprinklers. The first Nebraska barn was
ventilated naturally and equipped with a
sprinkler system over the feed line and fans
over the freestalls. The second Nebraska
barn was ventilated mechanically using evaporative
cooling, fans installed over the freestalls,
and a sprinkler system over the feed
line. Evaporative cooling did not favorably
modify the barn environment. It increased or
decreased humidity and offset the effect of a
lower barn temperatures, resulting in greater
respiration rates of cows and overall less cow
comfort than other systems that provided fans
or sprinklers or both.