The Impact of Adopting On‐Animal Sensors on Reproductive Performance in Spring Calving, Pasture‐Based, Dairy Herds

This study utilised passively collected calving and artificial insemination ( AI ) records from 141 commercial herds equipped with ‘wearables’ (on‐animal sensors for oestrus detection) to investigate their reproductive performance before and after adoption, relative to 1158 ‘non‐wearable' reference herds matched on geographic location, herd size, planned start of calving date and milk production. The associations between wearable status (wearable vs. reference herds) and key reproductive metrics were analysed using linear regression. Before adoption, wearable herds had a 1.1% point greater 6‐week calving rate and 2.9% point 3‐week submission rate and maintained this advantage throughout. Wearable herds had increased AI duration, by 20 days, after adoption compared with no change in the reference herds. After limiting the AI records to between 3 and 45 days after the seasonal mating start date, there were no differences in non‐return rate. Overall, there was no evidence to support improvement, or deterioration, in reproductive performance following the adoption of wearables. We interpret this to mean that the potential benefits of wearables to labour efficiency and management can be captured without jeopardising reproductive performance; albeit, farmers choosing to adopt wearable technologies should not assign a value for improved reproductive performance when estimating return on investment.