Cooling Effect of Fabric Air Ducting System for Loose Housing Dairy Cows in an Open-Sided Barn
Curtain-sided bams with circulation fans above stall are commonly used to house dairy cows in China.Many of the circulation fans currently used are unable to provide appropriate cooling, especially for the naturally ventilated shed, and can result in decreased feed intake and milk production.Designed for alleviating heat stress and improving animal comfort, a system consisting of an air cooler and a 30 m fabric air duct (FAD) was integrated to evenly distribute cooling air to targeted zones above stall beds.The system was evaluated in an open sided dairy barn in Tianjin, China.For the stalls equipped with FAD system, air velocity reached 1.1 m/s and higher at the 0.7 m height plane of the stall space, and was more uniformly distributed.Compared to the stalls equipped with only circulation fans, the FAD system lowered air temperature by 1.5 ℃, and increased relative humidity by 8.1%.On average, Temperature Humidity Index (THI) and Equivalent Temperature Index (ETI) were decreased by 0.5 and 0.6,respectively.After a 15-day operation of the system, rectal temperatures of the treated dairy cows were significantly lowered (P < 0.05).The result also showed that the treated group had higher milk production.These findings suggest the FAD can be an effective cooling alternative for naturally ventilated dairy barns.
Temperature Humidity Index Equivalent Temperature Index freestall cooling natural ventilation
Lina Xie Chaoyuan Wang Zhiyuan Gui Lu Zhang Zhengxiang Shi Baoming Li Luyu Ding Chuntao Jia
Department of Agricultural Structure and Bioenvironmental Engineering, China Agricultural University Hai Lin Dairy Farm, Tianjin 301718, China
国际会议
The 2015 International Symposium on Animal Environment and Welfare(动物环境和福利国际研讨会)
重庆
英文
26-33
2015-10-23（万方平台首次上网日期，不代表论文的发表时间）