Materials and Methods
Instrumentation
Each barn was equipped with four temperature & humidity dataloggers and two black globes. A temperature & humidity datalogger was also placed outside (away from the barn and shaded) with an unshaded black globe temperatures (BGT) sensor and associated datalogger. The temperature & humidity dataloggers were placed near the center of each quadrant of each barn (Locations #3 in plan view in Figure 1). If a barn was physically divided into quadrants, the existing quadrants were used (regardless of number of stalls or cows) to better represent conditions experienced by individual groups of cows. Two barns (TV-OHC and TV-OHW) were only divided lengthwise into two cow groups, so each of these sections was subdivided conceptually according to the number of stalls to form quadrants of roughly equal size. Each datalogger (w/sensor) was attached to the most-central post in the respective quadrant (within a section of freestalls) about 8 ft. above the floor of the cow alley. This height was selected to obtain readings that were fairly representative of the cows' occupied zone, yet prevent cows from damaging the dataloggers. A black globe was hung between two posts near the center of either the northwest or northeast quadrant of each barn at a height of about 8 ft. Globes were placed within the same respective quadrant for each pair of barns.