Validation of a technology for objectively measuring behaviour in dairy cows and its application for oestrous detection

Devices (IceTag ® ActivityMonitor) using accelerometer technology to determine the behaviour of cows (proportion of time lying, standing, active and step count) were attached to 15 cows (2 per cow) and validated between devices and against observed behaviour. For standing and active, 95% of paired (within cow) one minute data points were within 7% points, 95% of the lying data points were within 1% point, and 95% of stepping data were within 3 steps. The device recorded 100% of lying bouts within ±1 minute of visually observed data. In a second experiment, 16 lactating dairy cows were fitted with IceTag ® s and the relationship between behaviour profiles and oestrus evaluated. Blood progesterone concentration and twicedaily visual observations were used to identify precisely ovulation events and four algorithms, based on active and lying behaviour, were developed. A 24 hour rolling mean of activity and a slope threshold of 0.2 calculated for either the previous 10 hours (Activity24/10) or 5 hours (Activity24/5) correctly identified 93% of oestrous events, with 21% and 18% false positive alerts, respectively. Two further algorithms, Lying 5.5% between midnight and 05:00hrs identified 50% and 64% of oestrous events, with 36% and 18% false positive alerts, respectively. In a third experiment using 30 cows, 56 oestrous events were identified through milk progesterone profiles and visual observation. Algorithm Activity24/10 and Activity24/5 identified 84% and 76% of oestrous events respectively. The IceTag ® accurately recorded