Continuous and Wireless Skin Contact and Ear Implant Temperature Measurements and Relations to the Core Body Temperature of Heat Stressed Dairy Cows

Abstract. Most dairy producers attempt to control the complex microenvironments inside their barns, and to do so they often rely on various types of electric fans as well as operational guidelines based solely on local temperature and/or relative humidity readings. Such constraints often produce an inefficient and suboptimal rate of air movement through the cow-occupied space. The present study attempts to find a viable alternative to this problem. Since well-being and productivity are directly related to core body temperature (CBT), this measure should be integral to any attempt to quantify a cow‘s level of heat stress. However, if any particular significance is to be assigned to CBT, the CBT must be continuously measured to enable the timely control of the airflow. Consequently, this work aims to rely on multi-disciplinary approaches to (i) design ultra-low-power, low-cost, non-invasive skin and core body temperature sensors and (ii) design a framework for precision system operation based on the real-time CBT. A wireless, skin- or core-body-temperature reader, which can be affixed to existing straps, is designed and tested. Using a low-power wireless frontend, the device can give the sensor a longer life. A framework that utilizes the real-time CBT measurements, integrated with ambient temperature and relative humidity readings, is discussed in terms of how it could achieve the desirable micro-environmental conditions. The present study thus seeks to provide commercial dairy farmers with a less invasive way to gather data from their dairy cows in order to make key decisions concerning system operations and their animals‘ well-being, and as a consequence to maximize milk production in an economical and environmentally sustainable way.