West Central Research and Outreach Center, University of Minnesota, Morris, MN 56267, USA.
J Anim Sci. 2013 Jul;91(7):3429-35. doi: 10.2527/jas.2012-5824. Epub 2013 May 8.
The objective of this investigation was to determine the effect of a reduced nocturnal temperature (RNT) regimen on performance of weaned pigs and energy consumption during the nursery phase of production. The age of weaned pigs assigned to experiments ranged from 16 to 22 d. In Exp. 1, 3 stations conducted 2 trials under a common protocol that provided data from 6 control rooms (CON; 820 pigs) and 6 RNT rooms (818 pigs). Two mirror-image nursery rooms were used at each station. Temperature in the CON room was set to 30°C for the first 7 d, then reduced by 2°C per week through the remainder of the experiment. Room temperature settings were held constant throughout the day and night. The temperature setting in the RNT room was the same as CON during the first 7 d, but beginning on the night of d 7, the room temperature setting was reduced 6°C from the daytime temperature from 1900 to 0700 h. The use of heating fuel and electricity were measured weekly in each room. Overall, ADG (0.43 kg), ADFI (0.62 kg), and G:F (0.69) were identical for CON and RNT rooms. Consumption of heating fuel [9,658 vs. 7,958 British thermal units (Btu)·pig(-1)·d(-1)] and electricity (0.138 vs. 0.125 kilowatt-hour (kWh)·pig(-1)·d(-1)] were not statistically different for CON and RNT rooms, respectively. In Exp. 2, 4 stations conducted at least 2 trials that provided data from 9 CON rooms (2,122 pigs) and 10 RNT rooms (2,176 pigs). Experimental treatments and protocols were the same as Exp. 1, except that the RNT regimen was imposed on the night of d 5 and the targeted nighttime temperature reduction was 8.3°C. Neither final pig BW (21.8 vs. 21.5 kg; SE = 0.64), ADG (0.45 vs. 0.44 kg; SE = 0.016), ADFI (0.61 vs. 0.60 kg; SE = 0.019), nor G:F (0.75 vs. 0.75; SE = 0.012) were different for pigs housed in CON or RNT rooms, respectively. Consumption of heating fuel and electricity was consistently reduced in RNT rooms for all 4 stations. Consumption of heating fuel (10,019 vs. 7,061 Btu·pig(-1)·d(-1); SE = 1,467) and electricity (0.026 vs. 0.021 kWh·pig-1·d-1; SE = 0.004) were lower (P < 0.05) in the RNT rooms compared with CON rooms. This represents a 30% reduction in heating fuel use and a 20% reduction in electrical use with no differences in pig growth performance or health. From these experiments, we conclude that imposing a RNT regimen from 1900 to 0700 h is effective in reducing energy costs in the nursery without compromising pig performance, which will reduce production costs and decrease emissions of greenhouse gases.
本研究的目的是确定夜间温度降低（RNT）方案对断奶仔猪生产育肥期性能和能量消耗的影响。断奶仔猪的年龄在 16-22 日龄之间。在实验 1 中，3 个站点根据相同的方案进行了 2 次试验，提供了 6 个对照室（CON；820 头猪）和 6 个 RNT 室（818 头猪）的数据。每个站点使用两个镜像式育肥室。CON 室的温度在前 7 天设定为 30°C，然后每周降低 2°C，直至实验结束。昼夜温度设定保持不变。RNT 室的温度设定与 CON 室相同，但从第 7 天晚上开始，房间温度设定在 1900-0700 小时期间，比白天温度降低 6°C。每周在每个房间测量加热燃料和电力的使用情况。总体而言，CON 和 RNT 室的 ADG（0.43 公斤）、ADFI（0.62 公斤）和 G:F（0.69）相同。CON 和 RNT 室的加热燃料消耗[9658 比 7958 英国热量单位（Btu）·猪（-1）·d（-1）]和电力消耗（0.138 比 0.125 千瓦时（kWh）·猪（-1）·d（-1））分别没有统计学差异。在实验 2 中，4 个站点进行了至少 2 次试验，提供了 9 个 CON 室（2122 头猪）和 10 个 RNT 室（2176 头猪）的数据。实验处理和方案与实验 1 相同，只是 RNT 方案在第 5 天晚上实施，目标夜间温度降低 8.3°C。CON 和 RNT 室的最终猪体重（21.8 比 21.5 公斤；SE = 0.64）、ADG（0.45 比 0.44 公斤；SE = 0.016）、ADFI（0.61 比 0.60 公斤；SE = 0.019）和 G:F（0.75 比 0.75；SE = 0.012）均无差异。所有 4 个站点的 RNT 室的加热燃料和电力消耗均持续减少。RNT 室的加热燃料消耗（10019 比 7061 英国热量单位（Btu）·猪（-1）·d（-1）；SE = 1467）和电力消耗（0.026 比 0.021 千瓦时·猪（-1）·d（-1）；SE = 0.004）均低于 CON 室（P<0.05）。这意味着，在不影响猪生长性能的情况下，采用 1900-0700 小时的夜间温度降低方案可以有效降低育肥室的能源成本，从而降低生产成本并减少温室气体排放。
