An evaluation of the Heatime® system on a dairy farm in California

Abstract

The objective of this study is to detect possible differences between the breeder and the heat detection system Heatime® related to progesterone concentrations on a large dairy in central California. In total 132 cows have been sampled in a period of seven working days. Three groups were used: group 1 consisted of cows that were positively assigned as in heat by the breeder as well as by Heatime®. Group 2 consisted of cows only assigned as in heat by Heatime®. Group 3 consisted of cows only assigned as in heat by the breeder. The dairy also used OvSynch as a synchronization program on several cows. This research found a significant difference between the positive predictive value (PPV) of Heatime® and the breeder (p <0,001). When excluding the synchronized cows, this significance disappeared (p = 0,103). When checking the synchronized cows only, there was a significant difference between the PPV of Heatime® and the breeder (p <0,001). It is an added value that Heatime® is able to detect cows that are actually in estrus, where the breeder has difficulties to recognize them. Heatime® gave several false positives, but the system is said to be ‘better safe than sorry’. Therefore the opinion of the breeder remains important. Because of specific settings of the Heatime® system on this dairy it was difficult to analyze it for scientific purposes. In the field it works very well. As a final note there can be said that Heatime® is a good additional measuring device for heat detection, but it still is a matter of human judgment and it needs to be used with good care by a well-trained breeder.