Since odor concentration was significantly related to the
ambient temperature for all four types of barns (P < 0.01), a
second-order polynomial relationship between odor concentration
and ambient temperature was obtained for each
type of room. The r2 values were 0.76, 0.63, and 0.65 for the
gestation, farrowing, and finishing rooms, respectively.
Figure 5 shows the correlation of odor concentration and
ambient temperature for the finishing rooms. The nursery
rooms did not have a strong correlation between odor
concentration and ambient temperature (r2 = 0.38). The
reason might be that the great difference between room
temperature of the nursery rooms and the ambient temperature
(average 25.0°C and 7.9°C, respectively) required a
very low ventilation rate, which made the ventilation rate rely
less on the ambient temperature than it did in the other types
of rooms.