The experiment was conducted in a commercial research finishing facility in southwestern Minnesota. The building was double-curtain-sided and naturally ventilated. Each 3- by 5.5-m pen had a completely slatted flooring over a deep pit for manure storage, and was equipped with a 5-hole stainless steel, dry selffeeder and cup waterer for ad libitum access to feed
and water. The building had an automated feeding system (FEEDPro, Feedlogic Corp., Willmar, MN) that delivered and measured feed on an individual pen basis.