Sensor and Video: Two Complementary Approaches for Evaluation of Dairy Cow Behavior after Calving Sensor Attachment

SIMPLE SUMMARY: We analyzed whether attaching sensors to the tail of cows for the early detection of calving leads to behavioral changes. In this study, we combined conventional video analysis with data from digital sensor technologies. To detect the potential agitation of cows after calving sensor attachment, we analyzed cow activity behavior. Based on the combined results of video and sensor analysis, there was no clear evidence that attaching sensors to the tail generally altered the ethological pattern of all cows analyzed. However, the investigation of individual cows showed an increase in the frequency of tail raising and rubbing the tail after calving sensor attachment. These changes would be worth analyzing in more detail on a larger scale. ABSTRACT: Studies evaluating calving sensors provided evidence that attaching the sensor to the tail may lead to changes in the cows’ behavior. Two different calving sensors were attached to 18 cows, all of which were equipped with a rumen bolus to record their activity. Two methodological approaches were applied to detect potential behavioral changes: analysis of homogeneity of variance in cow activity (5 days pre-sensor and 24 h post-sensor) and analysis of video-recorded behavior (12 h pre- and post-sensor, respectively) in a subgroup. The average results across the sample showed no significant changes in the variability of activity and no statistically significant mean differences in most visually analyzed behaviors, namely walking, eating, drinking, social interaction, tail raising, rubbing the tail, and the number of standing and lying bouts after calving sensor attachment. In addition to considering mean values across all cows, individual cow investigations revealed an increased number of time slots showing a significant increase in the variability of activity and an increased frequency of tail raising and rubbing the tail on objects after calving sensor attachment in some cows, which should be investigated in more detail on a larger scale.