Optimization of Surface Wetting to Cool Broiler Chickens

Thumbnail Image
Tao, Xiuping
Major Professor
Committee Member
Journal Title
Journal ISSN
Volume Title
Xin, Hongwei
Distinguished Professor Emeritus
Research Projects
Organizational Units
Organizational Unit
Agricultural and Biosystems Engineering

Since 1905, the Department of Agricultural Engineering, now the Department of Agricultural and Biosystems Engineering (ABE), has been a leader in providing engineering solutions to agricultural problems in the United States and the world. The department’s original mission was to mechanize agriculture. That mission has evolved to encompass a global view of the entire food production system–the wise management of natural resources in the production, processing, storage, handling, and use of food fiber and other biological products.

In 1905 Agricultural Engineering was recognized as a subdivision of the Department of Agronomy, and in 1907 it was recognized as a unique department. It was renamed the Department of Agricultural and Biosystems Engineering in 1990. The department merged with the Department of Industrial Education and Technology in 2004.

Dates of Existence

Historical Names

  • Department of Agricultural Engineering (1907–1990)

Related Units

Journal Issue
Is Version Of

Surface wetting to cool broiler chickens (46±3 d, 2.8± 0.1 kg) was investigated under 18 acute thermal conditions formed by three dry-bulb temperatures (tdb, 35, 38, and 41 oC) × two dew-point temperatures (tdp,19.4 and 26.1oC) × three air velocity (V, 0.2, 0.7 and 1.2 m ·s-1). The synergistic effects of tdb and tdp were expressed in terms of vapor pressure deficit of the air (VPDair). Surface temperature of the cooled birds was 1.9-2.5 oC lower than that of their control counterparts. Core body temperature (tb) rise of the cooled birds was 1.2, 1.6, and 1.7 oC lower than that of the control birds at 35, 38, and 41 oC, respectively. Increasing V narrowed the difference in tb between the cooled and the control broilers, 2.0, 1.4, and 1.2 oC for V of 0.2, 0.7, and 1.2 m ·s-1, respectively. Increasing tdp from 19.4 to 26.1 oC produced only 0.2 oC overall difference in tb. Results of this study demonstrate that surface wetting coupled with good air movement, as in the case of tunnel ventilation, is effective in relieving heat stress of the birds even under relatively humid conditions. The cooling water needs, expressed as spray interval at a nominal spray dosage of 22 ml ·bird-1 (SI22, min) and evaporation rate (ER, ml/min ·kg0.67), were optimized by relating the SI22 or ER to the thermal conditions, of the form, SI22 = 70.50 – 27.14 . V – 4.84 .VPDair, and ER = - 0.0471 + 0.1700 . V + 0.0297 .VPDair.


This is an ASAE Meeting Presentation, Paper No. 034088.

Wed Jan 01 00:00:00 UTC 2003