The daily activity pattern of dairy cows is likely to be a crucial parameter for the assessment of housing conditions, as changes in activity can reflect stress reactions. Reliable estimates of activity patterns can only be achieved via automated 24-hour recording. For this purpose, we validated a new manageable system, the Actiwatch Activity Monitoring System (AMS), which has previously been used in human research (e.g. sleep analysis).

The AMS is a very compact accelerometer (27 x 26 x 9 mm, 34 g) which stores activity counts in intervals from 2 s to 15 min for long time periods (e.g. 45 days at a sample interval of 1 min), until they can be read out through an interface. To validate the system for its use with cattle, we attached AMS devices to the hind leg (distal to the metatarsal joint) of 12 dairy cows. After habituation, we measured the cows’ activity at intervals of one minute for 10 days. Simultaneous video observation was conducted for five days (24-h time-lapse mode) to relate the recordings of the AMS to particular behavioral patterns. All 12 cows accepted the AMS devices without any signs of disturbance.

In particular, we will present results on:

• the effects of attaching the device to different legs
• the consistency between different devices, tested by attaching two devices to the same leg and comparing AMS recordings with video recordings
• whether and which specific behavioral activities can be distinguished by the AMS (e.g. resting, locomotion)

Paper presented at Measuring Behavior 2002 , 4^th International Conference on Methods and Techniques in Behavioral Research, 27-30 August 2002, Amsterdam, The Netherlands

© 2002 Noldus Information Technology bv