Wearable wireless sensor for estrus detection in cows by conductivity and temperature measurements

A probe for wireless monitoring of the vaginal conductivity and temperature in cows has been developed, manufactured, and tested in-situ for approximately 48 hours. The cow was filmed during testing, and events and activities correlated with the obtained data. This allowed systematic variations due to stress, position and activity, as well as circadian patterns, to be identified. The probe has three electrode pairs for conductivity measurements that are probed consecutively, which allow electrode position related variations to be investigated. One of the main applications of this type of sensor is automated estrus detection, which is of high economic importance to farmers. Prior work has mainly relied on manual and/or implanted probes, both of which are inconvenient for commercial applications, and the collected data has usually consisted of a relatively limited number of points. This probe collects data from multiple positions at user defined intervals for extended periods of time, thus giving a much more complete picture of the behavior of the investigated quantities.