The knowledge of bioenergetics and building ventilation rate in intensive livestock housing is important for efficient design and operation of modern animal production facilities. However, information is limited about ventilation performance and house-level heat and moisture production rates of laying hens in contemporary cage-free facilities. Therefore, the objectives of this study were: (i) to determine building ventilation rate (VR) and the associated measurement uncertainty through in-situ calibration of ventilation fans and monitoring of fans runtime in a fully-open aviary laying hen house (~140,000 Dekalb White hens); and (ii) to quantify total heat production (THP) of the cage-free hens that is partitioned into house-level latent heat production (LHP) and sensible heat production (SHP) via indirect calorimetry and energy balance methods. THP, SHP, and LHP were expressed for light and dark periods, as well as for time-weighted daily mean, to evaluate the effect of hens’ diurnal activities on bioenergetics. VR averaged 4.0 ± 0.4 m3 h−1 hen−1, ranging from 0.8 to 9.1 m3 h−1 hen−1 for different seasons. VR uncertainty varied with the operational static pressure (SP) and averaged 9.5% at 10 Pa, 12.7% at 25 Pa, and 17.3% at 40 Pa. Overall, daily mean values were 7.5 ± 0.2 W kg−1 for THP, 4.8 ± 0.3 W kg−1 for SHP, and 2.7 ± 0.2 W kg−1 for LHP. THP decreased by 40% during the dark period (5.1 ± 0.3 W kg−1) compared to the light period (8.5 ± 0.3 W kg−1).

中文翻译：

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现代鸟舍系统中 dekalb 白母鸡的通风性能和生物能学

集约化畜舍中的生物能量学和建筑​​通风率知识对于现代动物生产设施的有效设计和运行非常重要。然而，关于现代无笼设施中蛋鸡的通风性能和鸡舍级热量和水分生产率的信息是有限的。因此，本研究的目标是：(i) 通过在全开放式蛋鸡舍（~140,000德卡尔布白母鸡）；(ii) 通过间接量热法和能量平衡方法量化分为鸡舍潜热产生 (LHP) 和显热产生 (SHP) 的无笼母鸡的总产热 (THP)。THP、SHP 和 LHP 表示明暗时期以及时间加权的日平均值，以评估母鸡的昼夜活动对生物能量学的影响。VR 平均为 4.0 ± 0.4 m3 h−1 hen−1，不同季节的范围从 0.8 到 9.1 m3 h−1 hen−1。VR 不确定性随操作静压 (SP) 而变化，10 Pa 时平均为 9.5%，25 Pa 时为 12.7%，40 Pa 时为 17.3%。总体而言，THP 的日平均值为 7.5 ± 0.2 W kg-1，4.8 ± SHP 为 0.3 W kg-1，LHP 为 2.7 ± 0.2 W kg-1。与光照期 (8.5 ± 0.3 W kg-1) 相比，黑暗期 (5.1 ± 0.3 W kg-1) 的 THP 降低了 40%。1 m3 h−1 hen−1 用于不同季节。VR 不确定性随操作静压 (SP) 而变化，10 Pa 时平均为 9.5%，25 Pa 时为 12.7%，40 Pa 时为 17.3%。总体而言，THP 的日平均值为 7.5 ± 0.2 W kg-1，4.8 ± SHP 为 0.3 W kg-1，LHP 为 2.7 ± 0.2 W kg-1。与光照期 (8.5 ± 0.3 W kg-1) 相比，黑暗期 (5.1 ± 0.3 W kg-1) 的 THP 降低了 40%。1 m3 h−1 hen−1 用于不同季节。VR 不确定性随操作静压 (SP) 而变化，10 Pa 时平均为 9.5%，25 Pa 时为 12.7%，40 Pa 时为 17.3%。总体而言，THP 的日平均值为 7.5 ± 0.2 W kg-1，4.8 ± SHP 为 0.3 W kg-1，LHP 为 2.7 ± 0.2 W kg-1。与光照期 (8.5 ± 0.3 W kg-1) 相比，黑暗期 (5.1 ± 0.3 W kg-1) 的 THP 降低了 40%。